Patent Application
20230131233
A PCT Request Form is filed concurrently with this specification as part of the present application. Each application that the present application claims benefit of or priority to as identified in the concurrently filed PCT Request Form is incorporated by reference herein in its entirety and for all purposes.
Semiconductor fabrication often involves patterning schemes and other processes whereby some materials are selectively etched to prevent etching of other exposed surfaces of a substrate. As device geometries become smaller and smaller, high etch selectivity processes are desirable to achieve effective etching of desired materials without plasma assistance.
The background description provided herein is for the purposes of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Details of one or more implementations of the subject matter described in this specification are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages will become apparent from the description, the drawings, and the claims. The following, non-limiting implementations are considered part of the disclosure; other implementations will be evident from the entirety of this disclosure and the accompanying drawings as well.
In some embodiments, an apparatus for semiconductor processing may be provided. The apparatus may include a processing chamber including chamber walls that at least partially bound a chamber interior, and a chamber heater configured to heat the chamber walls, a pedestal positioned within the chamber interior and including a substrate heater having a plurality of light emitting diodes (LEDs) configured to emit light with wavelengths in the range of 400 nanometers (nm) and 800 nm, a window positioned above the substrate heater, having a top surface and a bottom surface opposite the top surface that faces the LEDs, and including a material transparent to light with wavelengths in the range of 400 nm and 800 nm, and three or more substrate supports, each substrate having a substrate support surface vertically offset from the window and configured to support a substrate such that the window and the substrate supported by the three or more substrate supports are offset by a nonzero distance, and a gas distribution unit including one or more fluid inlets, a faceplate having a plurality of through-holes fluidically connected to the one or more fluid inlets and to the chamber interior, and having a front surface partially bounding the chamber interior, and a unit heater thermally connected to the faceplate such that heat can be transferred between the faceplate and the unit heater.
In some embodiments, each substrate support may include a material transparent to light with wavelengths in the range of 400 nm and 800 nm.
In some embodiments, the three or more substrate supports may each include quartz.
In some embodiments, the substrate support surfaces may be positioned closer to a center axis of the window than an outer diameter of the window top surface.
In some embodiments, each substrate support may include a temperature sensor configured to detect a temperature of a substrate positioned on the substrate support surface.
In some such embodiments, the temperature sensor may be a thermocouple.
In some embodiments, each substrate support surface may be vertically offset from the LEDs by a distance of between 1 millimeter and 100 millimeters.
In some embodiments, the window may include quartz.
In some such embodiments, the window may further include a sapphire coating.
In some embodiments, the window may not have hole in the center.
In some embodiments, the top surface of the window may be nonplanar.
In some embodiments, the bottom surface of the window may be nonplanar.
In some embodiments, the bottom surface of the window may be in contact with at least a first set of the LEDs.
In some embodiments, the pedestal may further include a sidewall, and an outer region of the window may be thermally connected to the sidewall such that heat can be transferred between the outer region and the sidewall.
In some embodiments, the substrate heater may further include a printed circuit board, by which the LEDs are supported, that includes a reflective material.
In some embodiments, the pedestal may include a bowl in which the substrate heater is positioned, and the bowl may include one or more sidewalls having an exterior surface that comprises reflective material.
In some embodiments, the pedestal may further include a pedestal cooler that is thermally connected to the LEDs such that heat can be transferred between the LEDs and the pedestal cooler, includes at least one fluid channel within the pedestal, and is configured to flow a cooling fluid within the at least one fluid channel.
In some such embodiments, the pedestal may further include a pedestal heater configured to heat one or more exterior surfaces of the pedestal.
In some further such embodiments, the pedestal heater may be a resistive heater.
In some embodiments, the pedestal may include a fluid inlet and is configured to flow a fluid between the LEDs and the bottom surface of the window.
In some embodiments, the pedestal may be configured to move vertically.
In some embodiments, the pedestal may be configured to move vertically to cause a vertical offset gap between the substrate support surfaces of the substrate support and the front surface of the faceplate of between about 2 millimeters (mm) and about 70 mm.
In some embodiments, a first set of LEDs may be arranged in a first circle having a first radius around a center axis of the substrate heater, and equally spaced apart from each other, and a second set of LEDs may be arranged in a second circle having a second radius larger than the first radius around the center axis, and equally spaced apart from each other.
In some embodiments, a first set of LEDs may be electrically connected to form a first electrical zone, a second set of LEDs may be electrically connected to form a second electrical zone, and the first and second electrical zones may be independently controllable.
In some embodiments, the plurality of LEDs may include more than about 1,000 LEDs, and the plurality of LEDs may be grouped to create at least about 80 independently controllable electrical zones.
In some such embodiments, the plurality of LEDs may include more than about 5,000 LEDs.
In some embodiments, each LED may be configured to emit visible blue light.
In some embodiments, each LED may be configured to emit visible white light.
In some embodiments, each LED may use about 1.5 watts or less at full power.
In some embodiments, each LED may use about 4 watts or less at full power.
In some embodiments, each LED may be a chip on board LED.
In some embodiments, each LED may be a surface mounted diode LED.
In some embodiments, the gas distribution unit may further include a second unit heater configured to heat the faceplate.
In some such embodiments, the second unit heater may be a resistive heater.
In some embodiments, the unit heater may include at least one fluid channel and may be configured to flow a heat transfer fluid within the at least one fluid channel.
In some embodiments, the apparatus may further include a mixing plenum fluidically connected to, and upstream of, at least one of the one or more fluid inlets of the gas distribution unit.
In some embodiments, the apparatus may further include one or more sensors configured to measure one or more metrics of the visible light emitted by the LEDs.
In some such embodiments, the one or more sensors may be photodetectors.
In some such embodiments, the one or more metrics may include the light emitted by the LEDs.
In some embodiments, the apparatus may further include a pyrometer having a detector and an emitter, in which the gas distribution unit may include a port that extends through the faceplate and that includes a sensor window, the emitter or the detector may be connected to the port and sensor window through a fiberoptic cable, and the emitter or the detector may be positioned in the pedestal and below the window.
In some such embodiments, the pyrometer may be configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 micron, or between about 1 and about 4 microns.
In some such embodiments, the pyrometer may be configured to detect emissions having wavelengths of about 1 micron, about 1.1 micron, and between about 1 and about 4 microns.
In some such embodiments, the sensor window may be located in a center region of the faceplate.
In some embodiments, the chamber walls may include aluminum.
In some embodiments, the chamber walls may include a plastic coating.
In some embodiments, the chamber walls may include a metal with a yttria coating.
In some embodiments, the chamber walls may include a metal with a zirconia coating.
In some embodiments, the chamber walls may include a metal or metal alloy with an aluminum oxide coating.
In some embodiments, the apparatus may further include a vacuum pump configured to evacuate the chamber interior, and processing chamber may be configured to operate in a pressure range of about 0.1 Torr to about 100 Torr.
In some embodiments, the apparatus may further include a controller having a processor and one or more non-transitory memory devices storing instructions for causing the LEDs to emit the visible light having wavelengths between 400 nm and 800 nm.
In some such embodiments, the apparatus may further include a cooling gas source fluidically connected to the one or more fluid inlets, in which the one or more non-transitory memory devices further store instructions for causing the cooling gas to flow onto the substrate.
In some further such embodiments, the pedestal may be configured to move vertically, and the one or more non-transitory memory devices may further store instructions for causing the pedestal to move vertically and cause the substrate to be offset from the faceplate by a nonzero gap less than or equal to about 5 mm, and the cooling gas may be flowed onto the substrate while the substrate is offset from the faceplate by the non-zero gap.
In some embodiments, a method may be provided. The method may include supporting a substrate in a processing chamber having chamber walls using only a pedestal having a plurality of substrate supports that each contact an edge region of the substrate, heating, while the substrate is supported by only the plurality of substrate supports, the substrate to a first temperature by emitting visible light from a plurality of light emitting diodes (LEDs) under the substrate, in which the visible light has wavelengths between 400 nanometers (nm) and 800 nm, and etching, while the substrate is supported by only the plurality of substrate supports and while the substrate is at the first temperature, a surface of the substrate.
In some embodiments, the method may further include cooling, while the substrate is supported by only the plurality of substrate supports, the substrate by one or more of flowing a cooling gas onto the substrate, and moving the pedestal vertically so that the substrate is offset from a faceplate of a gas distribution unit by a first nonzero offset distance, and thereby causing heat to transfer from the substrate to the faceplate through noncontact radiation.
In some such embodiments, the cooling may be by both flowing the cooling gas and positioning the substrate at the first nonzero offset distance from the faceplate.
In some further such embodiments, the first nonzero offset distance may be less than or equal to 5 mm.
In some such embodiments, the cooling gas may include one or more of hydrogen and helium.
In some embodiments, the method may further include heating, while the substrate is supported by only the plurality of substrate supports, the chamber walls to a second temperature, and heating, while the substrate is supported by only the plurality of substrate supports, a faceplate of a gas distribution unit positioned above the substrate to a third temperature, in which the etching is performed while the chamber walls are heated to the second temperature and the faceplate is heated to the third temperature.
In some such embodiments, the second temperature and the third temperature may be between 30° C. and 150° C.
In some embodiments, the supporting, heating, and etching may be performed while the processing chamber is at a pressure between about 0.1 Torr and about 100 Torr.
In some embodiments, the supporting, heating, and etching may be performed while the processing chamber is at a pressure between about 20 Torr and about 200 Torr.
In some embodiments, the first temperature may be between about 30° C. and about 200° C.
In some embodiments, the first temperature may be between about 100° C. and about 500° C.
In some embodiments, the method may further include measuring, using one or more temperature sensors, a temperature of the substrate, and adjusting, based on the measuring, a power of at least a first set of the plurality of LEDs during the heating, maintaining, and/or etching.
In some such embodiments, the one or more temperature sensors may include one or more of a temperature sensor in at least one of the substrate supports, and a pyrometer with an emitter configured to emit radiation onto the substrate and a detector configured to receive emissions from the substrate, a temperature of the substrate, in which the detector is configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 micron, or between about 1 and about 4 microns.
In some further such embodiments, the emitter may be configured to detect emissions having wavelengths of about 1 micron, about 1.1 micron, and between about 1 and about 4 microns.
In some further such embodiments, the one or more temperature sensors may include both the temperature sensor in at least one of the substrate supports and the pyrometer.
In some embodiments, the method may further include adjusting a power of at least a first set of the plurality of LEDs, heating, after the adjusting while the substrate is supported by only the plurality of substrate supports, the substrate to a second temperature by emitting visible light from the LEDs, and etching, while the substrate is supported by only the plurality of substrate supports and while the substrate is at the second temperature, a bottom surface of the substrate.
In some such embodiments, the method may further include measuring, using one or more temperature sensors, a temperature of the substrate, and the adjusting is performed based, at least in part, on the measuring.
In some further such embodiments, the one or more temperature sensors may include one or more of a temperature sensor in at least one of the substrate supports, and a pyrometer with an emitter configured to emit radiation onto the substrate and a receiver configured to receive emissions from the substrate, a temperature of the substrate, in which the detector is configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 micron, or between about 1 and about 4 microns.
In some further embodiments, the emitter may be configured to detect emissions having wavelengths of about 1 micron, about 1.1 micron, and between about 1 and about 4 microns.
In some further embodiments, the one or more temperature sensors may include both the temperature sensor in at least one of the substrate supports and the pyrometer.
In some embodiments, the supporting may further include supporting the substrate using only a plurality of substrate supports that include a material transparent to visible light having wavelengths between 400 nm and 800 nm.
In some embodiments, a method may be provided. The method may include emitting visible light from a plurality of light emitting diodes (LEDs) in a processing chamber, in which the visible light has wavelengths between 400 nanometers (nm) and 800 nm, measuring, using one or more sensors configured to detect the visible light emitted from the plurality of LEDs, one or more metrics of the visible light emitted by the LEDs, and adjusting, based at least in part on the measuring, a power of a first set of the plurality of LEDs, in which the first set includes less LEDs than the plurality of LEDs.
In some embodiments, the measuring may further include measuring the visible light using a photodetector.
In some such embodiments, the photodetector may be outside the processing chamber that and connected via fiberoptic cable to a port in the processing chamber.
In some embodiments, a pedestal for use in a semiconductor processing chamber may be provided. The pedestal may include a window having a top surface and a bottom surface opposite the top surface, and including a material transparent to visible light with wavelengths in the range of 400 nm and 800 nm, and three or more substrate supports, each substrate support including a material transparent to visible light with wavelengths in the range of 400 nm and 800 nm, having a substrate support surface configured to support a substrate such that the window and the substrate supported by the three or more substrate are offset by a nonzero distance, and having a temperature sensor configured to detect a temperature of a substrate positioned on the substrate support surface.
In some embodiments, the three or more substrate supports may each include quartz.
In some embodiments, the substrate support surfaces may be positioned closer to a center axis of the window than an outer diameter of the window top surface.
In some embodiments, each temperature sensor may be a thermocouple.
In some embodiments, each substrate support surface may be vertically offset from the window by a distance between about 5 and about 30 millimeters.
In some embodiments, the pedestal may further include a substrate heater having a plurality of light emitting diodes (LEDs) configured to emit vising light with wavelengths in the range of 400 nm and 800 nm.
In some embodiments, a pedestal for use in a semiconductor processing chamber may be provided. The pedestal may include a substrate heater having a plurality of light emitting diodes (LEDs) configured to emit vising light with wavelengths in the range of 400 nanometers (nm) and 800 nm, and a window having a top surface and a bottom surface opposite the top surface, and comprising a material transparent to visible light with wavelengths in the range of 400 nm and 800 nm, in which one or more of the top surface and the bottom surface are nonplanar surfaces.
In some embodiments, both the top surface and the bottom surface may be nonplanar surfaces.
In some embodiments, the bottom surface of the window may be in contact with at least a first set of the LEDs.
In some embodiments, the pedestal may further include a sidewall, and an outer region of the window may be thermally connected to the sidewall such that heat can be transferred between the outer region and the sidewall.
In some embodiments, the substrate heater may further includes a printed circuit board, by which the LEDs are supported, that includes a reflective material.
In some embodiments, the pedestal may include a bowl in which the substrate heater is positioned, the bowl may include one or more sidewalls having an exterior surface that comprises reflective material.
In some embodiments, the pedestal may further include a pedestal cooler that is thermally connected to the LEDs such that heat can be transferred between the LEDs and the pedestal cooler, includes at least one fluid channel within the pedestal, and is configured to flow a cooling fluid within the at least one fluid channel.
In some such embodiments, the pedestal may further include a pedestal heater configured to heat one or more exterior surfaces of the pedestal.
In some further such embodiments, the pedestal heater may be a resistive heater.
In some embodiments, the pedestal may include a fluid inlet and may be configured to flow a fluid between the LEDs and the bottom surface of the window.
In some embodiments, a first set of LEDs may be arranged in a first circle having a first radius around a center axis of the substrate heater, and equally spaced apart from each other, and a second set of LEDs may be arranged in a second circle having a second radius larger than the first radius around the center axis, and equally spaced apart from each other.
In some embodiments, a first set of LEDs may be electrically connected to form a first electrical zone, a second set of LEDs may be electrically connected to form a second electrical zone, and the first and second electrical zones may be independently controllable.
In some embodiments, the plurality of LEDs may include more than 1,000 LEDs, and the plurality of LEDs may be grouped to create at least about 80 independently controllable electrical zones.
In some such embodiments, the plurality of LEDs may include more than about 5,000 LEDs.
In some embodiments, each LED may be configured to emit visible blue light.
In some embodiments, each LED may be configured to emit visible white light.
In some embodiments, each LED may use about 1.5 watts or less at full power.
In some embodiments, each LED may use about 4 watts or less at full power.
In some embodiments, each LED may be a chip on board LED.
In some embodiments, each LED may be a surface mounted diode LED.
In some embodiments, an apparatus may be provided. The apparatus may include a processing chamber including chamber walls that at least partially bound a chamber interior, a pedestal positioned within the chamber interior and configured to support a substrate, and a pyrometer having a detector and an emitter, in which the processing chamber includes a port that extends through a surface of the processing chamber that is above the pedestal, and that includes a sensor window, the emitter or the detector is connected to the port and sensor window through a fiberoptic cable, the emitter or the detector is positioned in the pedestal, and the pyrometer is configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 micron, or between about 1 and about 4 microns.
In some embodiments, the pyrometer may be configured to detect emissions having wavelengths of about 1 micron, about 1.1 micron, and between about 1 and about 4 microns.
In some embodiments, the sensor window may be located in a center region of processing chamber.
In some embodiments, the processing chamber may be further include a gas distribution unit including one or more fluid inlets and a faceplate having a plurality of through-holes fluidically connected to the one or more fluid inlets and to a chamber interior, and having a front surface partially bounding the chamber interior, and the port may extend through the front surface of the faceplate.
In some embodiments, the apparatus may further include one or more sensors configured to measure one or more metrics of the visible light emitted by the LEDs.
In some such embodiments, the one or more sensors may be photodetectors.
In some such embodiments, the one or more metrics may include light emitted by the LEDs.
In some embodiments, a method may be provided. The method may include supporting a substrate in a processing chamber having chamber walls using only a pedestal having a plurality of substrate supports that each contact an edge region of the substrate, heating, while the substrate is supported by only the plurality of substrate supports, the substrate to a first temperature by emitting visible light from a plurality of light emitting diodes (LEDs) under the substrate, in which the visible light has wavelengths between 400 nanometers (nm) and 800 nm, and cooling, while the substrate is supported by only the plurality of substrate supports, the substrate by one or more of flowing a cooling gas onto the substrate, and moving the pedestal vertically so that the substrate is offset from a faceplate of a gas distribution unit by a first nonzero offset distance less than or equal to 5 mm, and thereby causing heat to transfer from the substrate to the faceplate through noncontact radiation.
In some embodiments, the cooling may be by flowing the cooling gas onto the substrate.
In some embodiments, the cooling may be by positioning the substrate at the first nonzero offset distance from the faceplate.
In some embodiments, the cooling may be by both flowing the cooling gas and positioning the substrate at the first nonzero offset distance from the faceplate.
In some such embodiments, the cooling gas may include one of or more of hydrogen and helium.
In the following description, numerous specific details are set forth to provide a thorough understanding of the presented embodiments. The disclosed embodiments may be practiced without some or all of these specific details. In other instances, well-known process operations have not been described in detail to not unnecessarily obscure the disclosed embodiments. While the disclosed embodiments will be described in conjunction with the specific embodiments, it will be understood that it is not intended to limit the disclosed embodiments.
Semiconductor fabrication processes often involve patterning and etching of various materials, including conductors, semiconductors, and dielectrics. Some examples include conductors, such as metals or carbon; semiconductors, such as silicon or germanium; and dielectrics, such as silicon oxide, aluminum dioxide, zirconium dioxide, hafnium dioxide, silicon nitride, and titanium nitride. Atomic layer etching (“ALE”) processes provide one class of etching techniques that involve repeated variations in etch conditions over the course of an etch operation. ALE processes remove thin layers of material using sequential self-limiting reactions. Generally, an ALE cycle is the minimum set of operations used to perform an etch process one time, such as etching a monolayer. The result of one ALE cycle is that at least some of a film layer on a substrate surface is etched. Typically, an ALE cycle includes a modification operation to form a reactive layer, followed by a removal operation to remove or etch only this reactive layer. The cycle may include certain ancillary operations such as removing one of the reactants or byproducts. Generally, a cycle contains one instance of a unique sequence of operations.
As an example, a conventional ALE cycle may include the following operations: (i) delivery of a reactant gas to perform a modification operation, (ii) purging of the reactant gas from the chamber, (iii) delivery of a removal gas and an optional plasma to perform a removal operation, and (iv) purging of the chamber. In some embodiments, etching may be performed nonconformally. The modification operation generally forms a thin, reactive surface layer with a thickness less than the un-modified material. In an example modification operation, a substrate may be chlorinated by introducing chlorine into the chamber. Chlorine is used as an example etchant species or etching gas, but it will be understood that a different etching gas may be introduced into the chamber. The etching gas may be selected depending on the type and chemistry of the substrate to be etched. A plasma may be ignited and chlorine reacts with the substrate for the etching process; the chlorine may react with the substrate or may be adsorbed onto the surface of the substrate. The species generated from a chlorine plasma can be generated directly by forming a plasma in the process chamber housing the substrate or they can be generated remotely in a process chamber that does not house the substrate, and can be supplied into the process chamber housing the substrate.
In some instances, a purge may be performed after a modification operation. In a purge operation, non-surface-bound active chlorine species may be removed from the process chamber. This can be done by purging and/or evacuating the process chamber to remove the active species, without removing the adsorbed layer. The species generated in a chlorine plasma can be removed by simply stopping the plasma and allowing the remaining species decay, optionally combined with purging and/or evacuation of the chamber. Purging can be done using any inert gas such as N2, Ar, Ne, He and their combinations.
In a removal operation, the substrate may be exposed to an energy source to etch the substrate by directional sputtering (this may include activating or sputtering gas or chemically reactive species that induce removal). In some embodiments, the removal operation may be performed by ion bombardment using argon or helium ions. During removal, a bias may be optionally turned on to facilitate directional sputtering. In some embodiments, ALE may be isotropic; in some other embodiments ALE is not isotropic when ions are used in the removal process.
In various examples, the modification and removal operations may be repeated in cycles, such as about 1 to about 30 cycles, or about 1 to about 20 cycles. Any suitable number of ALE cycles may be included to etch a desired amount of film. In some embodiments, ALE is performed in cycles to etch about 1 Å to about 50 Å of the surface of the layers on the substrate. In some embodiments, cycles of ALE etch between about 2 Å and about 50 Å of the surface of the layers on the substrate. In some embodiments, each ALE cycle may etch at least about 0.1 Å, 0.5 Å, or 1 Å.
In some instances, prior to etching, the substrate may include a blanket layer of material, such as silicon or germanium. The substrate may include a patterned mask layer previously deposited and patterned on the substrate. For example, a mask layer may be deposited and patterned on a substrate including a blanket amorphous silicon layer. The layers on the substrate may also be patterned. Substrates may have “features” such as fins, or holes, which may be characterized by one or more of narrow and/or re-entrant openings, constrictions within the feature, and high aspect ratios. One example of a feature is a hole or via in a semiconductor substrate or a layer on the substrate. Another example is a trench in a substrate or layer. In various instances, the feature may have an under-layer, such as a barrier layer or adhesion layer. Non-limiting examples of under-layers include dielectric layers and conducting layers, e.g., silicon oxides, silicon nitrides, silicon carbides, metal oxides, metal nitrides, metal carbides, and metal layers.
The use of plasma during conventional etching presents numerous challenges and disadvantages. For instance, it is generally desirable to create the same plasma conditions for each ALE cycle of a single substrate as well as for all substrates in a batch, but it can be difficult to repeatedly recreate the same plasma conditions due to some plasmas changing due to accumulation of material in the process chamber. Additionally, many conventional ALE processes may cause damage to exposed components of the substrate, such as silicon oxide, may cause defects, and may increase the top-to-bottom ratio of a pattern and increase the pattern loading. Defects may lead to pattern-missing to the extent that the device may be rendered useless. Plasma-assisted ALE also utilizes small radicals, i.e., deeply dissociated radicals, that are more aggressive which causes them to remove more material than may be desired, thereby reducing the selectivity of this etching. As a result, conventional ALE techniques are often unsuitable for selectively etching some materials, such as aluminum dioxide, zirconium dioxide, hafnium dioxide, silicon nitride, and titanium nitride. It is therefore desirable to determine new etching techniques and apparatuses that do not use a plasma and that are able to provide rapid and precise temperature control of a substrate during processing.
More generally, apparatus designed or configured to provide variable reaction conditions over the course of an etch process, regardless of whether that process is an ALE process or some other etch process that employs varying conditions. In certain embodiments, the apparatus is designed or configured to provide rapidly varying temperature over the course of an etch process.
Provided herein are methods and apparatuses for rapidly and precisely controlling a substrate’s temperature during semiconductor processing, including performing etching using thermal energy, rather than or in addition to plasma energy, to drive the modification and removal operations. In certain embodiments, etching that relies upon chemical reactions in conjunction with primarily thermal energy, not a plasma, to drive the chemical reactions in the modification and removal operations may be considered “thermal etching”. This etching is not limited to ALE; it is applicable to any etching technique.
In certain embodiments, thermal etching processes, such as those employing one or more thermal cycles have relatively fast heating and cooling and relatively precise temperature control. In some cases, these features may be leveraged to provide good throughput and/or to reduce nonuniformity and wafer defects.
However, many conventional etching apparatuses do not have the ability to adjust and control the temperature of the substrate with adequate speed. For example, while some etching apparatuses may be able to heat a substrate to multiple temperatures, they can do so only slowly, or they may not be able to reach the desired temperature ranges, or they may not be able to maintain the substrate temperature for the desired time and at the desired temperature ranges. Similarly, typical etching apparatuses are often unable to cool the substrate fast enough to enable high throughput or cool the substrate to the desired temperature ranges. For some applications, it is desirable to reduce the temperature ramp times as much as possible, such as to less than about 120 seconds in some embodiments, but many conventional etching apparatuses cannot heat, cool, or both, a substrate less than that time; it may take some apparatuses multiple minutes to cool and/or heat a substrate which slows throughput.
In various embodiments, apparatuses described herein are designed or configured to rapidly heat and cool a wafer, and precisely control a wafer’s temperature. In some embodiments, the wafer is rapidly heated and its temperature is precisely controlled using, in part, visible light emitted from light emitting diodes (LEDs) positioned in a pedestal under the wafer. The visible light may have wavelengths that include and range between 400 nanometers (nm) and 800 nm. The pedestal may include various features for enabling wafer temperature control, such as a transparent window that may have lensing for advantageously directing or focusing the emitted light, reflective material also for advantageously directing or focusing the emitted light, and temperature control elements that assist with temperature control of the LEDs, the pedestal, and the chamber.
The apparatuses may also thermally isolate, or thermally “float,” the wafer within the processing chamber so that only the smallest thermal mass is heated, the ideal smallest thermal mass being just the substrate itself, which enables faster heating and cooling. The wafer may be rapidly cooled using a cooling gas and radiative heat transfer to a heat sink, such as a top plate (or other gas distribution element) above the wafer, or both. In some instances, the apparatus also includes temperature control elements within the processing chamber walls, pedestal, and top plate (or other gas distribution element), to enable further temperature control of the wafer and processing conditions within the chamber, such the prevention of unwanted condensation of processing gases and vapors.
The apparatuses may also be configured to implement various control loops to precisely control the wafer and the chamber temperatures (e.g., with a controller configured to execute instructions that cause the apparatus to perform these loops). This may include the use of various sensors that determine wafer and chamber temperatures as part of open loops and feedback control loops. These sensors may include temperature sensors in the wafer supports which contact the wafer and measure its temperature, and non-contact sensors such as photodetectors to measure light output of the LEDs and a pyrometer configured to measure the temperature of different types of wafers. As described in more detail below, some pyrometers determine an item’s temperature by emitting infrared or other optical signals at the item and measuring the signals reflected or emitted by the item. However, many silicon wafers cannot be measured by some pyrometers because the silicon can be optically transparent at various temperatures and with various treatments, e.g., doped or low doped silicon. For example, a low doped silicon wafer at a temperature less than 200° C. is transparent to infrared signals. The novel pyrometers provided herein are able to measure multiple types of silicon wafers at various temperatures.
The processing chamber 102 includes sides walls 112A, a top 112B, and a bottom 112C, that at least partially define the chamber interior 114, which may be considered a plenum volume. As stated herein, it may be desirable in some embodiments to actively control the temperature of the processing chamber walls 112A, top 112B, and bottom 112C in order to prevent unwanted condensation on their surfaces. Some emerging semiconductor processing operations flow vapors, such as water and/or alcohol vapor, onto the substrate which adsorb onto the substrate, but they may also undesirably adsorb onto the chamber’s interior surfaces. This can lead to unwanted deposition and etching on the chamber interior surfaces which can damage the chamber surfaces and cause particulates to flake off onto the substrate thereby causing substrate defects. In order to reduce and prevent unwanted condensation on the chamber’s interior surfaces, the temperature of chamber’s walls, top, and bottom may be maintained at a temperature at which condensation of chemistries used in the processing operations does not occur.
This active temperature control of the chamber’s surfaces may be achieved by using heaters to heat the chamber walls 112A, the top 112B, and the bottom 112C. As illustrated in
The chamber walls 112A, top 112B, and bottom 112C, may also be comprised of various materials that can withstand the chemistries used in the processing techniques. These chamber materials may include, for example, an aluminum, anodized aluminum, aluminum with a polymer, such as a plastic, a metal or metal alloy with a yttria coating, a metal or metal alloy with a zirconia coating, and a metal or metal alloy with aluminum oxide coating; in some instances the materials of the coatings may be blended or layers of differing material combinations, such as alternating layers of aluminum oxide and yttria, or aluminum oxide and zirconia. These materials are configured to withstand the chemistries used in the processing techniques, such as anyhydrous HF, water vapor, methanol, isopropyl alcohol, chlorine, fluorine gases, nitrogen gas, hydrogen gas, helium gas, and the mixtures thereof.
The apparatus 100 may also be configured to perform processing operations at or near a vacuum, such as at a pressure of about 0.1 Torr to about 100 Torr, or about 20 Torr to about 200 Torr, or about 0.1 Torr to about 10 Torr. This may include a vacuum pump 184 configured to pump the chamber interior 114 to low pressures, such as a vacuum having a pressure of about 0.1 Torr to about 100 Torr, including about 0.1 Torr to about 10 Torr, and about 20 Torr to about 200 Torr, or about 0.1 Torr to about 10 Torr.
Various features of the pedestal 104 will now be discussed. The pedestal 104 includes a heater 122 (encompassed by the dashed rectangle in
The heater’s plurality of LEDs may be arranged, electrically connected, and electrically controlled in various manners. Each LED may be configured to emit a visible blue light and/or a visible white light. In certain embodiments, white light (produced using a range of wavelengths in the visible portion of the EM spectrum) is used. In some semiconductor processing operations, white light can reduce or prevent unwanted thin film interference. For instance, some substrates have backside films that reflect different light wavelengths in various amounts, thereby creating an uneven and potentially inefficient heating. Using white light can reduce this unwanted reflection variation by averaging out the thin film interference over the broad visible spectrum provided by white light. In some instances, depending on the material on the back face of the substrate, it may be advantageous to use a visible non-white light, such as a blue light having a 450 nm wavelength, for example, in order to provide a single or narrow band of wavelength which may provide more efficient, powerful, and direct heating of some substrates that may absorb the narrow band wavelength better than white light.
Various types of LED may be employed. Examples include a chip on board (COB) LED or a surface mounted diode (SMD) LED. For SMD LEDs, the LED chip may be fused to a printed circuit board (PCB) that may have multiple electrical contacts allowing for the control of each diode on the chip. For example, a single SMD chip may have three diodes (e.g., red, blue, or green) that can be individually controllable to create different colors, for instance. SMD LED chips may range in size, such as 2.8 x 2.5 mm, 3.0 x 3.0 mm, 3.5 x 2.8 mm, 5.0 x 5.0 mm, and 5.6 x 3.0 mm. For COB LEDs, each chip can have more than three diodes, such as nine, 12, tens, hundreds or more, printed on the same PCB. COB LED chips typically have one circuit and two contacts regardless of the number of diodes, thereby providing a simple design and efficient single color application. The ability and performance of LEDs to heat the substrate may be measured by the watts of heat emitted by each LED; these watts of heat may directly contribute to heating the substrate.
In some embodiments, the LEDs may also be arranged along circles around the center of the substrate heater. In some instances, some LEDs may be arranged along circles while others may be arranged along arcs.
In some embodiments, the plurality of LEDs may include at least about 1,000 LEDs, including about 1,200, 1,500, 2,000, 3,000, 4,000, 5,000, or more than 6,000, for instance. Each LED may, in some instances, be configured to uses 4 watts or less at 100% power, including 3 watts at 100% power and 1 watt at 100% power. These LEDs may be arranged and electrically connected into individually controllable zones to enable temperature adjustment and fine tuning across the substrate. In some instances, the LEDs may be grouped into at least 20, for instance, independently controllable zones, including at least about 25, 50, 75, 80, 85 90, 95, or 100 zones, for instance. These zones may allow for temperature adjustments in the radial and azimuthal (i.e., angular) directions. These zones can be arranged in a defined pattern, such as a rectangular grid, a hexagonal grid, or other suitable pattern for generating a temperature profile as desired. The zones may also have varying shapes, such as square, trapezoidal, rectangular, triangular, obround, elliptical, circular, annular (e.g., a ring), partially annular (i.e., an annular sector), an arc, a segment, and a sector that may be centered on the center of the heater and have a radius less than or equal to the overall radius of the substrate heater’s PCB. For example, in
In certain embodiments, the substrate heater 122 is configured to heat the substrate to multiple temperatures and maintain each such temperatures for various durations. These durations may include the following non-limiting examples of at least about 1 second, at least about 5 seconds, at least about 10 seconds, at least about 30 seconds, at least about 60 seconds, at least about 90 seconds, at least about 120 second, at least about 150 seconds, or at least about 180 seconds. The substrate heater may be configured to heat the substrate to between about 50° C. and 600° C., including between about 50° C. and 150° C., including about 130° C., or between about 150° C. and 350° C., for example. The substrate heater may be configured to maintain the substrate at a temperature within these ranges for various durations, including the following non-limiting examples: at least about 1 second, at least about 5 seconds, at least about 10 seconds, at least about 30 seconds, at least about 60 seconds, at least about 90 seconds, at least about 120 seconds, at least about 150 seconds, or at least about 180 seconds, for example. Additionally, in some embodiments, the substrate heater 122 is configured to heat the substrate to any temperature within these ranges in less than about 60 seconds, less than about 45 seconds, less than about 30 seconds, or less than about 15 seconds, for instance. In certain embodiments, the substrate heater 122 is configured to heat a substrate at one or more heating rates, such as between at least about 0.1° C./second and at least about 20° C./second, for example.
The substrate heater may increase the temperature of the substrate by causing the LEDs to emit the visible light at one or more power levels, including at least about 80%, at least about 90%, at least about 95%, or at least about 100% power. In some embodiments, the substrate heater is configured to emit light between about 10 W and 4000 W, including at least about 10 W, at least about 30 W, at least about 0.3 kilowatt (kW), at least about 0.5kW, at least about 2 kW, at least about 3 kW, or at least about 4 kw. The apparatus is configured to supply between about 0.1 kw and 9 kW of power to the pedestal; the power supply is connected to the substrate heater through the pedestal but is not depicted in the Figures. During temperature ramps, the substrate heater may operate at the high powers, and may operate at the lower power levels (e.g., include between about 5 W and about 0.5 kW) to maintain the temperature of a heated substrate.
The pedestal may include reflective material on its internal surfaces that, during operation, reflects and directs the light emitted by the LEDs onto the backside of the substrate supported by the pedestal. In some such embodiments, the substrate heater may include such reflective material positioned on a top surface 140, as shown in
In some embodiments, the substrate heater may also include a pedestal cooler that is thermally connected to the LEDs such that heat generated by the plurality of LEDs can be transferred from the LEDs to the pedestal cooler. This thermal connection is such that heat can be conducted from the plurality of LEDs to the pedestal cooler along one or more heat flow pathways between these components. In some instances, the pedestal cooler is in direct contact with one or more elements of the substrate heater, while in other instances other conductive elements, such as thermally conductive plates (e.g., that comprise a metal) are interposed between the substrate heater and the pedestal cooler. Referring back to
As provided herein, it may be advantageous to actively heat the exterior surfaces of the processing chamber 102. In some instances, it may similarly be advantageous to heat the exterior surfaces of the pedestal 104 in order to prevent unwanted condensation and deposition on its external surfaces. As illustrated in
The pedestal may also include a window to protect the substrate heater, including the plurality of LEDs, from damage caused by exposure to the processing chemistries and pressures used during processing operations. As illustrated in
With the window 150 positioned above the substrate heater 122, the window 150 gets heated by the substrate heater 122 which can affect the thermal environment around the substrate. Depending on the material or materials used for the window 150, such as quartz, the window may retain heat and progressively retain more heat over the course of processing one or more substrates. This heat can get radiatively transferred to the substrate and therefore directly heat the substrate. In some instances, that the window can cause a temperature increase of between 50° C. and 80° C. above the heater temperature. This heat may also create a temperature gradient through the thickness, or in the vertical direction, of the window. In some instances, the top surface 152 is 30° C. hotter than the bottom surface 154. It may therefore be advantageous to adjust and configure the chamber to account for and reduce the thermal effects of the window. As described in more detail below, this may include detecting the substrate’s temperature and adjusting the substrate heater to account for the heat retained by the window.
This may also include various configurations of the pedestal, such as actively cooling the window. In some embodiments, like that shown in
In some embodiments, the window may be placed in direct, thermal contact with the substrate heater and the pedestal cooler may be configured to cool both the PCB and the window. In some embodiments, as also shown in
As shown in
The pedestal 104 is therefore configured, in some embodiments, to support the substrate 118 by thermally floating, or thermally isolating, the substrate within the chamber interior 114. The pedestal’s 104 plurality of substrate supports 108 are configured to support the substrate 118 such that the thermal mass of the substrate 118 is reduced as much as possible to the thermal mass of just the substrate 118. Each substrate support 108 may have a substrate support surface 120 that provides minimal contact with the substrate 118. The number of substrate supports 108 may range from at least 3 to, for example, at least 6 or more. The surface area of the support surfaces 120 may also be the minimum area required to adequately support the substrate during processing operations (e.g., in order to support the weight of the substrate and prevent inelastic deformation of the substrate). In some embodiments, the surface area of one support surface 120 may be less than about 0.1%, less than about 0.075%, less than about 0.05%, less than about 0.025%, or less than about 0.01%, for instance.
The substrate supports are also configured to prevent the substrate from being in contact with other elements of the pedestal, including the pedestal’s surfaces and features underneath the substrate. As seen in
The substrate 118 is also offset from the substrate heater 122 (as measured in some instances from a top surface of the substrate heater 122 which may be the top surface of the LEDs 124) by a distance 160. This distance 160 affects numerous aspects of heating the substrate 118. In some instances, the LEDs 124 provide a nonuniform heating pattern, which increases as the distance 160 decreases; conversely, this nonuniform heating pattern is reduced by increasing the distance 160. In some instances as the distance 160 increases, the heating efficiency decreases across the substrate and decreases more in the edge region and causes nonuniform heating of the substrate. In some embodiments, a distance 160 of between about 10 mm and 90 mm, about 5 mm and 100 mm, including between 10 mm and 30 mm, for instance, provides a substantially uniform heating pattern and acceptable heating efficiency.
As stated, the substrate supports 108 are configured to support the substrate 118 above the window. In some embodiments, these substrate supports are stationary and fixed in position; they are not lift pins or a support ring. In some embodiments, at least a part of each substrate support 108 that includes the support surface 120 may be comprised of a material that is transparent at least to light emitted by LEDS 124. This material may be, in some instances, quartz or sapphire. The transparency of these substrate supports 108 may enable the visible light emitted by the substrate heater’s 122 LEDs to pass through the substrate support 108 and to the substrate 118 so that the substrate support 108 does not block this light and the substrate 118 can be heated in the areas where it is supported. This may provide a more uniform heating of the substrate 118 than with a substrate support comprising a material opaque to visible light. In some other embodiments, the substrate supports 108 may be comprised of a non-transparent material, such as zirconium dioxide (ZrO2).
In some embodiments, such as those shown in
In some embodiments, the substrate supports may each contain a temperature sensor that is configured to detect the temperature of the substrate positioned on the support surface of the substrate supports.
Referring back to
The gas distribution unit 110 is configured to flow process gases, which may include liquids and/or gases, such as a reactant, modifying molecules, converting molecules, or removal molecules, onto the substrate 118 in the chamber interior 114. As seen in
The through-holes 178 may be configured in various ways in order to deliver uniform gas flow onto the substrate. In some embodiments, these through-holes may all have the same outer diameter, such as between about 0.03 inches and 0.05 inches, including about 0.04 inches (1.016 mm). These faceplate through-holes may also be arranged throughout the faceplate in order to create uniform flow out of the faceplate.
Referring back to
In some embodiments, the gas distribution unit 110 may include a second unit heater 182 that is configured to heat the faceplate 176. This second unit heater 182 may include one or more resistive heating elements, fluid conduits for flowing a heating fluid, or both. Using two heaters 180 and 182 in the gas distribution unit 110 may enable various heat transfers within the gas distribution unit 110. This may include using the first and/or second unit heaters 180 and 182 to heat the faceplate 176 in order to provide a temperature-controlled chamber, as described above, in order to reduce or prevent unwanted condensation on elements of the gas distribution unit 110.
The apparatus 100 may also be configured to cool the substrate. This cooling may include flowing a cooling gas onto the substrate, moving the substrate close to the faceplate to allow heat transfer between the substrate and the faceplate, or both. Actively cooling the substrate enables more precise temperature control and faster transitions between temperatures which reduces processing time and improves throughput. In some embodiments, the first unit heater 180 that flows the heat transfer fluid through fluid conduits may be used to cool the substrate 118 by transferring heat away from the faceplate 176 that is transferred from the substrate 119. A substrate 118 may therefore be cooled by positioning it in close proximity to the faceplate 176, such as by a gap 186 of less than or equal to 5 mm or 2 mm, such that the heat in the substrate 118 is radiatively transferred to the faceplate 176, and transferred away from the faceplate 176 by the heat transfer fluid in the first unit heater 180. The faceplate 176 may therefore be considered a heat sink for the substrate 118 in order to cool the substrate 118.
In some embodiments, the apparatus 100 may further include a cooling fluid source 173 which may contain a cooling fluid (a gas or a liquid), and a cooler (not pictured) configured to cool the cooling fluid to a desired temperature, such as less than or equal to at least about 90° C., at least about 70° C., at least about 50° C., at least about 20° C., at least about 10° C., at least about 0° C., at least about -50° C., at least about -100° C., at least about -150° C., at least about -190° C., at least about -200° C., or at least about -250° C., for instance. The apparatus 100 includes piping to deliver the cooling fluid to the one or more fluid inlets 170, and the gas distribution unit 110 which is configured to flow the cooling fluid onto the substrate. In some embodiments, the fluid may be in liquid state when it is flowed to the chamber 102 and may turn to a vapor state when it reaches the chamber interior 114, for example if the chamber interior 114 is at a low pressure state, such as described above, e.g., between about 0.1 Torr and 10 Torr, or between about 0.1 Torr and 100 Torr, or between about 20 Torr and 200 Torr, for instance. The cooling fluid may be an inert element, such as nitrogen, argon, or helium. In some instances, the cooling fluid may include, or may only have, a non-inert element or mixture, such as hydrogen gas. In some embodiments, the flow rate of the cooling fluid into the chamber interior 114 may be at least about 0.25 liters per minute, at least about 0.5 liters per minute, at least about 1 liters per minute, at least about 5 liters per minute, at least about 10 liters per minute, at least about 50 liters per minute, or at least about 100 liters per minute, for example. In certain embodiments, the apparatus may be configured to cool a substrate at one or more cooling rates, such as at least about 5° C./second, at least about 10° C./second, at least about 15° C./second, at least about 20° C./second, at least about 30° C./second, or at least about 40° C./second.
In some embodiments, the apparatus 100 may actively cool the substrate by both moving the substrate close to the faceplate and flowing cooling gas onto the substrate. In some instances, the active cooling may be more effective by flowing the cooling gas while the substrate is in close proximity to the faceplate. The effectiveness of the cooling gas may also be dependent on the type of gas used.
The apparatuses provided herein can therefore rapidly heat and cool a substrate.
In some embodiments, the apparatus 100 may include a mixing plenum for blending and/or conditioning process gases for delivery before reaching the fluid inlets 170. One or more mixing plenum inlet valves may control introduction of process gases to the mixing plenum. In some other embodiments, the gas distribution unit 110 may include one or more mixing plenums within the gas distribution unit 110. The gas distribution unit 110 may also include one or more annular flow paths fluidically connected to the through-holes 178 which may equally distribute the received fluid to the through-holes 178 in order to provide uniform flow onto the substrate.
The apparatus 100 may also include one or more additional non-contact sensors for detecting the temperature of the substrate. One such sensor may be a new pyrometer that is capable of detecting numerous temperature ranges of a silicon substrate. It is desirable to detect the temperature of substrates having different treatments, e.g., whether the silicon is doped or not doped, at different temperatures ranges at which processing operations may occur, such as under about 200° C., greater than about 200° C. and less than about 600° C., or above 600° C. However, some pyrometers are not able to detect different substrates within these ranges. Some pyrometers measure the optical signals reflected or emitted by an object’s surface to determine the object’s temperature according to some calibration. However, many silicon wafers cannot be measured by these pyrometers because the silicon is optically transparent at various temperatures and with various treatments. As discussed above,
lightly doped, or undoped, silicon substrates have an emission signal from approximately 0.95 to 1.1 microns when the substrates are at or below about 300° C., that doped silicon substrates have an emission signal between about 1 and 4 microns when the substrates are below about 200° C., that silicon substrates have an emission signal at approximately 1 micron when around room temperature, such as under about 100° C. including, for instance 20° C., and that silicon substrates have an emission signal of about 8 to 15 microns when at temperatures over about 600° C. The new pyrometer is therefore configured to detect multiple emission ranges in order to detect multiple substrates, e.g., doped, low doped, or not doped, at various temperature ranges. This includes the configuration to detect emission ranges of about 0.95 microns to about 1.1 microns, about 1 micron, about 1 to about 4 microns, and/or about 8 to 15 microns. The new pyrometer is also configured to detect the temperature of a substrate at a shorter wavelength in order to differentiate the signal from the thermal noise of the chamber.
The new pyrometer may include an emitter configured to emit infrared signals and a detector configured to receive emissions. Referring to
The apparatus 100 may also include one or more optical sensors 198 to detect one or more metrics of the visible light emitted by the LEDs. In some embodiments, these optical sensors may be one or more photodetectors configured to detect the light and/or light intensity of the light emitted by the LEDs of the substrate heater. In
In some embodiments, the apparatus may further be configured to generate a plasma and use the plasma for some processing in various embodiments. This may include having a plasma source configured to generate a plasma within the chamber interior, such as a capacitively coupled plasma (CCP), an inductively coupled plasma (ICP), an upper remote plasma, and a lower remote plasma.
The apparatuses described herein are not limited to ALE etching operations. These apparatuses may be used with any etching technique.
Various techniques for using the apparatuses described herein will now be described.
In operation 1003, the substrate is heated to a first temperature while it is thermally floated in the chamber, i.e., while it is supported by only the substrate supports, using the substrate heater described herein that emits visible light having wavelengths between 400 nm and 800 nm from the plurality of LEDs. The first temperature may be any temperature provided herein, including between about 50° C. and about 600° C., including between about 50° C. and about 150° C., including about 130° C., or between about 150° C. and about 350° C., for example. The substrate may be rapidly heated to the first temperature, such as in less than about 60 seconds, less than about 45 seconds, less than about 30 seconds, or less than about 15 seconds, for instance. This may include powering the LEDs to their maximum power, which together may be greater than or equal to at least about 1 kW, at least about 2 kW, at least about 3 kW, at least about 4 kW, or at least about 9 kW of delivered power. As provided herein, this heating does not include a plasma or plasma generation.
In operation 1005, the substrate is maintained at the first temperature. This may include the substrate heater operating at lower power in order to maintain the substrate at a specific temperature. The LEDs may therefore be at a lower non-zero power level than during a temperature ramp up to provide some heating and maintain the substrate at the desired temperature. Examples may include between about 5 W and about 0.5 kW, including at least about 10 W, at least about 30 W, at least about 0.3 kW, or at least about 0.5 kW.
In operation 1007, the substrate is etched while at the first temperature. This etching may include flowing one or more gases to remove one or more modified layers of material. This etching also does not include a plasma or plasma generation.
In operation 1009, which may be optional in some embodiments, the substrate is actively cooled. This active cooling may include flowing the cooling the gas onto the substrate, moving the substrate in close proximity to the faceplate, or both as described herein. In some instances, this close proximity is less than or equal 5 mm, including 2 mm. The cooling gas may also include, for example, helium and nitrogen. Following operation 1009, in some instances, operations 1003 through 1009 may be repeated, with each sequence being considered a cycle.
In some embodiments, operations 1003, 1005, and 1007 may also be performed while the chamber walls, the faceplate, and/or the external surfaces of the pedestal are actively heated as described above. These items may be heated to between about 40° C. and about 150° C., including between about 80° C. and about 130° C., at least about 90° C. or at least about 120° C. Operations 1003, 1005, 1007, and 1009 may also be performed while the chamber interior is at a vacuum, which may be a pressure between about 0.1 Torr and about 10 Torr, or between about 0.1 Torr and about 100 Torr, or between about 20 Torr and 200 Torr.
The techniques provided herein may make various adjustments to the processing conditions. In some embodiments, these adjustments may be based on various received measurements, such as measurements of the substrate’s temperature and the LEDs. In some other embodiments, these adjustments may be performed in an open loop manner based on empirical or calculated data. In some embodiments, the techniques may follow a similar sequence as in
In some embodiments, the heating and maintaining operations may be based on empirical and measured data, such as empirically derived temperature drift of the apparatus, such as the window of the pedestal. As mentioned above, the window may retain heat throughout processing and act as an independent heater to the substrate. Adjustments may be made to the substrate heater in order to account for this drift, such as decreasing the overall power delivered to the LEDs of the substrate heater during the maintaining and etching operations, such as 1005, 1105, 1007, and 1107. These adjustments may be linear or non-linear, such as stepped or curved. This may also include adjustments to only some of the LEDs, such as to one or more of the independently controlled zones. For example, the center of the window may generate the most heat over time because the heat may not be able to be removed, while the edges of the window generate the least heat because some of this heat is transferred to the pedestal. Accordingly, to maintain uniform heating, one or more independently controllable zones of LEDs in the center of the substrate heater may be lowered to account for the increased heat in the center of the window. This may result in the same heat transferred to the substrate in the center region, with the heat generated by both the window and the substrate heater. Similarly, one or more independently controllable zones of LEDs in the outer region of the substrate heater may be lowered or kept the same to account for any additional heating, if any, caused by the exterior edge of the window.
In some embodiments as mentioned above, each LED may be individually controllable and in some such embodiments, a single LED may be adjusted to emit more or less light than one or more other LEDs. This adjustment may be made to account for a hot or cold spot on the substrate. For example, a spot on the wafer may have a temperature hotter or colder than other portions of the substrate and one LED underneath, or in close proximity to, that spot on the substrate may be adjusted to adjust the temperature at that spot. This may include decreasing the light emitted by the one LED to reduce the temperature at that spot or increasing the light emitted by the one LED to increase the temperature at that spot.
The techniques provided herein may also include feedback control loops for adjusting operating parameters, such as the power of one or more zones of the LEDs. These feedback loops may be implemented during the heating, maintaining, and etching operations described herein. This may include the using one or more of the sensors described herein to determine temperatures at the edge and in one or more locations on the substrate interior and adjust the substrate heater based on these measurements.
Similarly, the pyrometer described above may also detect the temperature of the substrate at a location on the substrate, such as its center. This temperature measurement may also be used, alone or in combination with the temperature sensors in the substrate supports, to adjust the substrate heater. For example, the pyrometer may indicate that the substrate center is higher than the first temperature and adjustments may be made to independently controllable LED zones around the center of the substrate, or to the whole substrate, in order to reduce the substrate’s temperature at this location. While these examples are made with respect to decreasing power of LEDs, the adjustments are not limited to such examples; the power of one or more independently controllable LED zones may be adjusted to increase the temperature at one or more locations on the substrate.
Another technique may measure the light emitted by the LEDs and adjust one or more independently controllable LED zones based on that measuring. This may include emitting the emitting visible light that has wavelengths between 400 nm and 800 nm from the LEDs, and measuring, using one or more sensors configured to detect the visible light emitted from the plurality of LEDs, one or more metrics of the visible light emitted by the LEDs. These sensors may include a photodetector described above. Based on this measured visible light, the power of one or more LED zones may be adjusted.
In some embodiments, the apparatuses described herein may include a controller that is configured to control various aspects of the apparatus in order to perform the techniques described herein. For example, referring back to
In some implementations, the controller 131 is part of an apparatus or a system, which may be part of the above-described examples. Such systems or apparatuses can include semiconductor processing equipment, including a processing tool or tools, chamber or chambers, a platform or platforms for processing, and/or specific processing components (a gas flow system, a substrate heating unit, a substrate cooling unit, etc.). These systems may be integrated with electronics for controlling their operation before, during, and after processing of a semiconductor wafer or substrate. The electronics may be referred to as the “controller,” which may control various components or subparts of the system or systems. The controller 966, depending on the processing parameters and/or the type of system, may be programmed to control any of the processes disclosed herein, including the delivery of processing gases, temperature settings (e.g., heating and/or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, positional and operation settings, wafer transfers into and out of a tool and other transfer tools and/or load locks connected to or interfaced with a specific system.
Broadly speaking, the controller 131 may be defined as electronics having various integrated circuits, logic, memory, and/or software that receive instructions, issue instructions, control operation, enable cleaning operations, enable endpoint measurements, and the like. The integrated circuits may include chips in the form of firmware that store program instructions, digital signal processors (DSPs), chips defined as application specific integrated circuits (ASICs), and/or one or more microprocessors, or microcontrollers that execute program instructions (e.g., software). Program instructions may be instructions communicated to the controller in the form of various individual settings (or program files), defining operational parameters for carrying out a particular process on or for a semiconductor wafer or to a system. The operational parameters may, in some embodiments, be part of a recipe defined by process engineers to accomplish one or more processing operations during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and/or dies of a wafer.
The controller 131, in some implementations, may be a part of or coupled to a computer that is integrated with, coupled to the system, otherwise networked to the system, or a combination thereof. For example, the controller may be in the “cloud” or all or a part of a fab host computer system, which can allow for remote access of the wafer processing. The computer may enable remote access to the system to monitor current progress of fabrication operations, examine a history of past fabrication operations, examine trends or performance metrics from a plurality of fabrication operations, to change parameters of current processing, to set processing operations to follow a current processing, or to start a new process. In some examples, a remote computer (e.g. a server) can provide process recipes to a system over a network, which may include a local network or the Internet. The remote computer may include a user interface that enables entry or programming of parameters and/or settings, which are then communicated to the system from the remote computer. In some examples, the controller 131 receives instructions in the form of data, which specify parameters for each of the processing operations to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process to be performed and the type of tool that the controller is configured to interface with or control. Thus as described above, the controller 131 may be distributed, such as by comprising one or more discrete controllers that are networked together and working towards a common purpose, such as the processes and controls described herein. An example of a distributed controller for such purposes would be one or more integrated circuits on a chamber in communication with one or more integrated circuits located remotely (such as at the platform level or as part of a remote computer) that combine to control a process on the chamber.
As noted above, depending on the process operation or operations to be performed by the apparatus, the controller 131 might communicate with one or more of other apparatus circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout a factory, a main computer, another controller, or tools used in material transport that bring containers of wafers to and from tool locations and/or load ports in a semiconductor manufacturing factory.
As also stated above, the controller is configured to perform any technique described above. This may include causing a substrate transfer robot to position the substrate in the chamber on the plurality of substrate supports causing power to be delivered to the LEDs so that they emit the visible light having wavelengths between 400 nm and 800 nm to heat the substrate to a first temperature, such as between 100° C. and 600° C., and causing etchant gases to flow into the chamber and etch the substrate. This may also include cooling, while the substrate is supported by only the plurality of substrate supports, the substrate by flowing the cooling gas onto the substrate, and/or moving the pedestal vertically so that the substrate is offset from a faceplate of a gas distribution unit by a first nonzero distance, and thereby causing heat to transfer from the substrate to the faceplate through noncontact radiation.
While the subject matter disclosed herein has been particularly described with respect to the illustrated embodiments, it will be appreciated that various alterations, modifications and adaptations may be made based on the present disclosure, and are intended to be within the scope of the present invention. It is to be understood that the description is not limited to the disclosed embodiments but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the scope of the claims.
It is to be further understood that the above disclosure, while focusing on a particular example implementation or implementations, is not limited to only the discussed example, but may also apply to similar variants and mechanisms as well, and such similar variants and mechanisms are also considered to be within the scope of this disclosure. For the avoidance of any doubt, it is also to be understood that the above disclosure is at least directed to the following numbered implementations, as well as to other implementations that are evident from the above disclosure.
Implementation 1: An apparatus for semiconductor processing, the apparatus including: a processing chamber including chamber walls that at least partially bound a chamber interior, and a chamber heater configured to heat the chamber walls, a pedestal positioned within the chamber interior and including a substrate heater having a plurality of light emitting diodes (LEDs) configured to emit light with wavelengths in the range of 400 nanometers (nm) and 800 nm, a window positioned above the substrate heater, having a top surface and a bottom surface opposite the top surface that faces the LEDs, and including a material transparent to light with wavelengths in the range of 400 nm and 800 nm, and three or more substrate supports, each substrate having a substrate support surface vertically offset from the window and configured to support a substrate such that the window and the substrate supported by the three or more substrate supports are offset by a nonzero distance, and a gas distribution unit including one or more fluid inlets, a faceplate having a plurality of through-holes fluidically connected to the one or more fluid inlets and to the chamber interior, and having a front surface partially bounding the chamber interior, and a unit heater thermally connected to the faceplate such that heat can be transferred between the faceplate and the unit heater.
Implementation 2: The apparatus of implementation 1, in which each substrate support includes a material transparent to light with wavelengths in the range of 400 nm and 800 nm.
Implementation 3: The apparatus of implementation 1, in which the three or more substrate supports each include quartz.
Implementation 4: The apparatus of implementation 1, in which the substrate support surfaces are positioned closer to a center axis of the window than an outer diameter of the window top surface.
Implementation 5: The apparatus of implementation 1, in which each substrate support includes a temperature sensor configured to detect a temperature of a substrate positioned on the substrate support surface.
Implementation 6: The apparatus of implementation 5, in which the temperature sensor is a thermocouple.
Implementation 7: The apparatus of implementation 1, in which each substrate support surface is vertically offset from the LEDs by a distance of between 1 millimeter and 100 millimeters.
Implementation 8: The apparatus of implementation 1, in which the window includes quartz.
Implementation 9: The apparatus of implementation 8, in which the window further includes a sapphire coating.
Implementation 10: The apparatus of implementation 1, in which the window does not have hole in the center.
Implementation 11: The apparatus of implementation 1, in which the top surface of the window is nonplanar.
Implementation 12: The apparatus of implementation 1, in which the bottom surface of the window is nonplanar.
Implementation 13: The apparatus of implementation 1, in which the bottom surface of the window is in contact with at least a first set of the LEDs.
Implementation 14: The apparatus of implementation 1, in which the pedestal further includes a sidewall, and an outer region of the window is thermally connected to the sidewall such that heat can be transferred between the outer region and the sidewall.
Implementation 15: The apparatus of implementation 1, in which the substrate heater further includes a printed circuit board, by which the LEDs are supported, that includes a reflective material.
Implementation 16: The apparatus of implementation 1, in which the pedestal includes a bowl in which the substrate heater is positioned, the bowl includes one or more sidewalls having an exterior surface that includes reflective material.
Implementation 17: The apparatus of implementation 1, in which the pedestal further includes a pedestal cooler that is thermally connected to the LEDs such that heat can be transferred between the LEDs and the pedestal cooler, includes at least one fluid channel within the pedestal, and is configured to flow a cooling fluid within the at least one fluid channel.
Implementation 18: The apparatus of implementation 17, in which the pedestal further includes a pedestal heater configured to heat one or more exterior surfaces of the pedestal.
Implementation 19: The apparatus of implementation 18, in which the pedestal heater is a resistive heater.
Implementation 20: The apparatus of implementation 1, in which the pedestal includes a fluid inlet and is configured to flow a fluid between the LEDs and the bottom surface of the window.
Implementation 21: The apparatus of implementation 1, in which the pedestal is configured to move vertically.
Implementation 22: The apparatus of implementation 1, in which the pedestal is configured to move vertically to cause a vertical offset gap between the substrate support surfaces of the substrate support and the front surface of the faceplate of between about 2 millimeters (mm) and about 70 mm.
Implementation 23: The apparatus of implementation 1, in which a first set of LEDs are arranged in a first circle having a first radius around a center axis of the substrate heater, and equally spaced apart from each other, and a second set of LEDs are arranged in a second circle having a second radius larger than the first radius around the center axis, and equally spaced apart from each other.
Implementation 24: The apparatus of implementation 1, in which a first set of LEDs are electrically connected to form a first electrical zone, a second set of LEDs are electrically connected to form a second electrical zone, and the first and second electrical zones are independently controllable.
Implementation 25: The apparatus of implementation 1, in which the plurality of LEDs includes more than about 1,000 LEDs, and the plurality of LEDs are grouped to create at least about 80 independently controllable electrical zones.
Implementation 26: The apparatus of implementation 25, in which the plurality of LEDs includes more than about 5,000 LEDs.
Implementation 27: The apparatus of implementation 1, in which each LED is configured to emit visible blue light.
Implementation 28: The apparatus of implementation 1, in which each LED is configured to emit visible white light.
Implementation 29: The apparatus of implementation 1, in which each LED uses about 1.5 watts or less at full power.
Implementation 30: The apparatus of implementation 1, in which each LED uses about 4 watts or less at full power.
Implementation 31: The apparatus of implementation 1, in which each LED is a chip on board LED.
Implementation 32: The apparatus of implementation 1, in which each LED is a surface mounted diode LED.
Implementation 33: The apparatus of implementation 1, in which the gas distribution unit further includes a second unit heater configured to heat the faceplate.
Implementation 34: The apparatus of implementation 33, in which the second unit heater is a resistive heater.
Implementation 35: The apparatus of implementation 1, in which the unit heater includes at least one fluid channel and is configured to flow a heat transfer fluid within the at least one fluid channel.
Implementation 36: The apparatus of implementation 1, further including a mixing plenum fluidically connected to, and upstream of, at least one of the one or more fluid inlets of the gas distribution unit.
Implementation 37: The apparatus of implementation 1, further including one or more sensors configured to measure one or more metrics of the visible light emitted by the LEDs.
Implementation 38: The apparatus of implementation 37, in which the one or more sensors are photodetectors.
Implementation 39: The apparatus of implementation 37, in which the one or more metrics includes the light emitted by the LEDs.
Implementation 40: The apparatus of implementation 1, further including a pyrometer having a detector and an emitter, in which the gas distribution unit includes a port that extends through the faceplate and that includes a sensor window, the emitter or the detector is connected to the port and sensor window through a fiberoptic cable, and the emitter or the detector is positioned in the pedestal and below the window.
Implementation 41: The apparatus of implementation 40, in which the pyrometer is configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 micron, or between about 1 and about 4 microns.
Implementation 42: The apparatus of implementation 40, in which the pyrometer is configured to detect emissions having wavelengths of about 1 micron, about 1.1 micron, and between about 1 and about 4 microns.
Implementation 43: The apparatus of implementation 40, in which the sensor window is located in a center region of the faceplate.
Implementation 44: The apparatus of implementation 1, in which the chamber walls include aluminum.
Implementation 45: The apparatus of implementation 1, in which the chamber walls include a plastic coating.
Implementation 46: The apparatus of implementation 1, in which the chamber walls include a metal with a yttria coating.
Implementation 47: The apparatus of implementation 1, in which the chamber walls include a metal with a zirconia coating.
Implementation 48: The apparatus of implementation 1, in which the chamber walls include a metal or metal alloy with an aluminum oxide coating.
Implementation 49: The apparatus of implementation 1, further including a vacuum pump configured to evacuate the chamber interior, processing chamber is configured to operate in a pressure range of about 0.1 Torr to about 100 Torr.
Implementation 50: The apparatus of implementation 1, further including a controller having a processor and one or more non-transitory memory devices storing instructions for causing the LEDs to emit the visible light having wavelengths between 400 nm and 800 nm.
Implementation 51: The apparatus of implementation 50, further including a cooling gas source fluidically connected to the one or more fluid inlets, in which the one or more non-transitory memory devices further store instructions for causing the cooling gas to flow onto the substrate.
Implementation 52: The apparatus of implementation 51, in which the pedestal is configured to move vertically, and the one or more non-transitory memory devices further store instructions for causing the pedestal to move vertically and cause the substrate to be offset from the faceplate by a non-zero gap less than or equal to about 5 mm, and the cooling gas is flowed onto the substrate while the substrate is offset from the faceplate by the non-zero gap.
Implementation 53: A method including supporting a substrate in a processing chamber having chamber walls using only a pedestal having a plurality of substrate supports that each contact an edge region of the substrate, heating, while the substrate is supported by only the plurality of substrate supports, the substrate to a first temperature by emitting visible light from a plurality of light emitting diodes (LEDs) under the substrate, in which the visible light has wavelengths between 400 nanometers (nm) and 800 nm, and etching, while the substrate is supported by only the plurality of substrate supports and while the substrate is at the first temperature, a surface of the substrate.
Implementation 54: The method of implementation 53, further including cooling, while the substrate is supported by only the plurality of substrate supports, the substrate by one or more of flowing a cooling gas onto the substrate, and moving the pedestal vertically so that the substrate is offset from a faceplate of a gas distribution unit by a first nonzero offset distance, and thereby causing heat to transfer from the substrate to the faceplate through noncontact radiation.
Implementation 55: The method of implementation 54, in which the cooling is by both flowing the cooling gas and positioning the substrate at the first nonzero offset distance from the faceplate.
Implementation 56: The method of implementation 55, in which the first nonzero offset distance is less than or equal to 5 mm.
Implementation 57: The method of implementation 54, in which the cooling gas includes one or more of hydrogen and helium.
Implementation 58: The method of implementation 53, further including heating, while the substrate is supported by only the plurality of substrate supports, the chamber walls to a second temperature; and heating, while the substrate is supported by only the plurality of substrate supports, a faceplate of a gas distribution unit positioned above the substrate to a third temperature, in which the etching is performed while the chamber walls are heated to the second temperature and the faceplate is heated to the third temperature.
Implementation 59: The method of implementation 58, in which the second temperature and the third temperature are between 30° C. and 150° C.
Implementation 60: The method of implementation 53, in which the supporting, heating, and etching are performed while the processing chamber is at a pressure between about 0.1 Torr and about 100 Torr.
Implementation 61: The method of implementation 53, in which the supporting, heating, and etching are performed while the processing chamber is at a pressure between about 20 Torr and about 200 Torr.
Implementation 62: The method of implementation 53, in which the first temperature is between about 30° C. and about 200° C.
Implementation 63: The method of implementation 53, in which the first temperature is between about 100° C. and about 500° C.
Implementation 64: The method of implementation 53, further including measuring, using one or more temperature sensors, a temperature of the substrate, and adjusting, based on the measuring, a power of at least a first set of the plurality of LEDs during the heating, maintaining, and/or etching.
Implementation 65: The method of implementation 64, in which the one or more temperature sensors include one or more of a temperature sensor in at least one of the substrate supports, and a pyrometer with an emitter configured to emit radiation onto the substrate and a detector configured to receive emissions from the substrate, a temperature of the substrate, in which the detector is configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 micron, or between about 1 and about 4 microns.
Implementation 66: The method of implementation 65, in which the emitter is configured to detect emissions having wavelengths of about 1 micron, about 1.1 micron, and between about 1 and about 4 microns.
Implementation 67: The method of implementation 65, in which the one or more temperature sensors includes both the temperature sensor in at least one of the substrate supports and the pyrometer.
Implementation 68: The method of implementation 53, further including adjusting a power of at least a first set of the plurality of LEDs, heating, after the adjusting while the substrate is supported by only the plurality of substrate supports, the substrate to a second temperature by emitting visible light from the LEDs, and etching, while the substrate is supported by only the plurality of substrate supports and while the substrate is at the second temperature, a bottom surface of the substrate.
Implementation 69: The method of implementation 68, further including measuring, using one or more temperature sensors, a temperature of the substrate, and the adjusting is performed based, at least in part, on the measuring.
Implementation 70: The method of implementation 69, in which the one or more temperature sensors include one or more of a temperature sensor in at least one of the substrate supports, and a pyrometer with an emitter configured to emit radiation onto the substrate and a receiver configured to receive emissions from the substrate, a temperature of the substrate, in which the detector is configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 micron, or between about 1 and about 4 microns.
Implementation 71: The method of implementation 70, in which the emitter is configured to detect emissions having wavelengths of about 1 micron, about 1.1 micron, and between about 1 and about 4 microns.
Implementation 72: The method of implementation 70, in which the one or more temperature sensors includes both the temperature sensor in at least one of the substrate supports and the pyrometer.
Implementation 73: The method of implementation 53, in which the supporting further includes supporting the substrate using only a plurality of substrate supports that include a material transparent to visible light having wavelengths between 400 nm and 800 nm.
Implementation 74: A method including emitting visible light from a plurality of light emitting diodes (LEDs) in a processing chamber, in which the visible light has wavelengths between 400 nanometers (nm) and 800 nm, measuring, using one or more sensors configured to detect the visible light emitted from the plurality of LEDs, one or more metrics of the visible light emitted by the LEDs, and adjusting, based at least in part on the measuring, a power of a first set of the plurality of LEDs, in which the first set includes less LEDs than the plurality of LEDs.
Implementation 75: The method of implementation 74, in which the measuring further includes measuring the visible light using a photodetector.
Implementation 76: The method of implementation 75, in which the photodetector is outside the processing chamber that and connected via fiberoptic cable to a port in the processing chamber.
Implementation 77: A pedestal for use in a semiconductor processing chamber, the pedestal including a window having a top surface and a bottom surface opposite the top surface, and including a material transparent to visible light with wavelengths in the range of 400 nm and 800 nm, and three or more substrate supports, each substrate support including a material transparent to visible light with wavelengths in the range of 400 nm and 800 nm, having a substrate support surface configured to support a substrate such that the window and the substrate supported by the three or more substrate are offset by a nonzero distance, and having a temperature sensor configured to detect a temperature of a substrate positioned on the substrate support surface.
Implementation 78: The pedestal of implementation 77, in which the three or more substrate supports each include quartz.
Implementation 79: The pedestal of implementation 77, in which the substrate support surfaces are positioned closer to a center axis of the window than an outer diameter of the window top surface.
Implementation 80: The pedestal of implementation 77, in which each temperature sensor is a thermocouple.
Implementation 81: The pedestal of implementation 77, in which each substrate support surface is vertically offset from the window by a distance between about 5 and about 30 millimeters.
Implementation 82: The pedestal of implementation 77, further including a substrate heater having a plurality of light emitting diodes (LEDs) configured to emit vising light with wavelengths in the range of 400 nm and 800 nm.
Implementation 83: A pedestal for use in a semiconductor processing chamber, the pedestal including a substrate heater having a plurality of light emitting diodes (LEDs) configured to emit vising light with wavelengths in the range of 400 nanometers (nm) and 800 nm, a window having a top surface and a bottom surface opposite the top surface, and including a material transparent to visible light with wavelengths in the range of 400 nm and 800 nm, in which one or more of the top surface and the bottom surface are nonplanar surfaces.
Implementation 84: The pedestal of implementation 83, in which both the top surface and the bottom surface are nonplanar surfaces.
Implementation 85: The pedestal of implementation 83, in which the bottom surface of the window is in contact with at least a first set of the LEDs.
Implementation 86: The pedestal of implementation 83, in which the pedestal further includes a sidewall, and an outer region of the window is thermally connected to the sidewall such that heat can be transferred between the outer region and the sidewall.
Implementation 87: The pedestal of implementation 83, in which the substrate heater further includes a printed circuit board, by which the LEDs are supported, that includes a reflective material.
Implementation 88: The pedestal of implementation 83, in which the pedestal includes a bowl in which the substrate heater is positioned, the bowl includes one or more sidewalls having an exterior surface that includes reflective material.
Implementation 89: The pedestal of implementation 83, in which the pedestal further includes a pedestal cooler that is thermally connected to the LEDs such that heat can be transferred between the LEDs and the pedestal cooler, includes at least one fluid channel within the pedestal, and is configured to flow a cooling fluid within the at least one fluid channel.
Implementation 90: The pedestal of implementation 89, in which the pedestal further includes a pedestal heater configured to heat one or more exterior surfaces of the pedestal.
Implementation 91: The pedestal of implementation 90, in which the pedestal heater is a resistive heater.
Implementation 92: The pedestal of implementation 83, in which the pedestal includes a fluid inlet and is configured to flow a fluid between the LEDs and the bottom surface of the window.
Implementation 93: The pedestal of implementation 83, in which a first set of LEDs are arranged in a first circle having a first radius around a center axis of the substrate heater, and equally spaced apart from each other, and a second set of LEDs are arranged in a second circle having a second radius larger than the first radius around the center axis, and equally spaced apart from each other.
Implementation 94: The pedestal of implementation 83, in which a first set of LEDs are electrically connected to form a first electrical zone, a second set of LEDs are electrically connected to form a second electrical zone, and the first and second electrical zones are independently controllable.
Implementation 95: The pedestal of implementation 83, in which the plurality of LEDs includes more than 1,000 LEDs, and the plurality of LEDs are grouped to create at least about 80 independently controllable electrical zones.
Implementation 96: The pedestal of implementation 95, in which the plurality of LEDs includes more than about 5,000 LEDs.
Implementation 97: The pedestal of implementation 83, in which each LED is configured to emit visible blue light.
Implementation 98: The pedestal of implementation 83, in which each LED is configured to emit visible white light.
Implementation 99: The pedestal of implementation 83, in which each LED uses about 1.5 watts or less at full power.
Implementation 100: The pedestal of implementation 83, in which each LED uses about 4 watts or less at full power.
Implementation 101: The pedestal of implementation 83, in which each LED is a chip on board LED.
Implementation 102: The pedestal of implementation 83, in which each LED is a surface mounted diode LED.
Implementation 103: An apparatus including a processing chamber including chamber walls that at least partially bound a chamber interior, a pedestal positioned within the chamber interior and configured to support a substrate, and a pyrometer having a detector and an emitter, in which the processing chamber includes a port that extends through a surface of the processing chamber that is above the pedestal, and that includes a sensor window, the emitter or the detector is connected to the port and sensor window through a fiberoptic cable, the emitter or the detector is positioned in the pedestal, and the pyrometer is configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 micron, or between about 1 and about 4 microns.
Implementation 104: The apparatus of implementation 103, in which the pyrometer is configured to detect emissions having wavelengths of about 1 micron, about 1.1 micron, and between about 1 and about 4 microns.
Implementation 105: The apparatus of implementation 103, in which the sensor window is located in a center region of processing chamber.
Implementation 106: The apparatus of implementation 103, in which the processing chamber further includes a gas distribution unit including one or more fluid inlets and a faceplate having a plurality of through-holes fluidically connected to the one or more fluid inlets and to a chamber interior, and having a front surface partially bounding the chamber interior, and the port extends through the front surface of the faceplate.
Implementation 107: The apparatus of implementation 103, further including one or more sensors configured to measure one or more metrics of the visible light emitted by the LEDs.
Implementation 108: The apparatus of implementation 107, in which the one or more sensors are photodetectors.
Implementation 109: The apparatus of implementation 107, in which the one or more metrics includes light emitted by the LEDs.
Implementation 110: A method including supporting a substrate in a processing chamber having chamber walls using only a pedestal having a plurality of substrate supports that each contact an edge region of the substrate, heating, while the substrate is supported by only the plurality of substrate supports, the substrate to a first temperature by emitting visible light from a plurality of light emitting diodes (LEDs) under the substrate, in which the visible light has wavelengths between 400 nanometers (nm) and 800 nm, and cooling, while the substrate is supported by only the plurality of substrate supports, the substrate by one or more of flowing a cooling gas onto the substrate, and moving the pedestal vertically so that the substrate is offset from a faceplate of a gas distribution unit by a first nonzero offset distance less than or equal to 5 mm, and thereby causing heat to transfer from the substrate to the faceplate through noncontact radiation.
Implementation 111: The method of implementation 110, in which the cooling is by flowing the cooling gas onto the substrate.
Implementation 112: The method of implementation 110, in which the cooling is by positioning the substrate at the first nonzero offset distance from the faceplate.
Implementation 113: The method of implementation 110, in which the cooling is by both flowing the cooling gas and positioning the substrate at the first nonzero offset distance from the faceplate.
Implementation 114: The method of implementation 110, in which the cooling gas includes one of or more of hydrogen and helium.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2021/023701 | 3/23/2021 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63003721 | Apr 2020 | US |
