Patent Application
20250135600
This application claims priority under 35 USC § 119 to Korean Patent Application No. 10-2023-0148786, filed on Nov. 1, 2023 in the Korean Intellectual Property Office (KIPO), the contents of which are herein incorporated by reference in their entirety.
Example embodiments relate to a polishing head and a polishing carrier apparatus having the same. More particularly, example embodiments relate to a polishing head configured to press a wafer onto a polishing pad and move the wafer, and a polishing carrier apparatus having the same.
In a chemical mechanical polishing (CMP) apparatus for planarizing a layer on a substrate, a removal rate of the thin layer may depend on pressure and temperature. In related arts, in order to control pressure, a polishing head may apply pressure to each ring-shaped zone through a flexible membrane provided in a lower portion of the polishing head. Additionally, in order to control temperature, temperature of a polishing pad provided under the substrate may be controlled to indirectly change temperature of the substrate. In this case, since the pressure may be controlled in a range of each ring-shaped zone, it may not be possible to control a local pressure, resulting in uneven flatness of the substrate. Further, due to indirect temperature control, a considerable amount of time may be consumed for the temperature control, causing a slurry to solidify and generate defects in the substrate. Additionally, unintended damage to a metal layer of the substrate may occur because direct cooling is not possible in a specific process.
Example embodiments provide a polishing head capable of improving polishing uniformity.
Example embodiments provide a polishing carrier apparatus including the polishing head.
According to some example embodiments, a substrate carrier configured to be detachably secured to a driving shaft and to pressurize and rotate a substrate, the substrate carrier including a flexible membrane, the flexible membrane including a main thin film having a first surface to be in contact with the substrate and a second surface opposite to the first surface, a plurality of vertical thin films extending from the second surface of the main thin film in a vertical direction, and a plurality of pressurizing chambers divided along a radial direction and about a central axis by the plurality of vertical thin films; a plurality of temperature elements in the main thin film and under the plurality of pressurizing chambers, the plurality of temperature elements configured to apply local heat to the substrate; and a plurality of pressure elements in the main thin film and respectively on the plurality of temperature elements, the plurality of pressure elements configured to apply local pressure to the main thin film.
According to some example embodiments, a polishing head includes a substrate carrier configured to be detachably secured to a driving shaft and to pressurize and rotate a substrate, the substrate carrier including a plurality of fluid passages that penetrate from an upper surface of the substrate carrier to a lower surface of the substrate carrier, the plurality of fluid passages spaced apart in a radial direction with respect to a central axis; a flexible membrane clamped to a lower portion of the substrate carrier, the flexible membrane including a main thin film, a plurality of vertical thin films extending from the main thin film in a vertical direction, and a plurality of pressurizing chambers defined by the plurality of vertical thin films, each of the plurality of pressurizing chambers connected to a corresponding fluid passage of the plurality of fluid passages, wherein the main thin film includes a plurality of main regions divided along the radial direction with respect to the central axis and a plurality of sub-regions sequentially arranged in a circumferential direction with respect to the central axis and provided within the plurality of main regions; a plurality of temperature elements respectively in the plurality of sub-regions of the main thin film and configured to apply local heat to the substrate; and a plurality of pressure elements respectively in the plurality of temperature elements and configured to apply local pressure to the main thin film.
According to some example embodiments, a polishing head includes a substrate carrier configured to be detachably secured to a driving shaft and to pressurize and rotate a substrate, the substrate carrier including a plurality of fluid passages that penetrate from an upper surface of the substrate carrier to a lower surface of the substrate carrier, the plurality of fluid passages spaced apart in a radial direction with respect to a central axis; a flexible membrane clamped to a lower portion of the substrate carrier, the flexible membrane including a main thin film, a plurality of vertical thin films extending from the main thin film in a vertical direction, and a plurality of pressurizing chambers defined by the plurality of vertical thin films, each of the plurality of pressurizing chambers connected to a corresponding fluid passage of the plurality of fluid passages, wherein the main thin film includes a plurality of main regions divided along the radial direction with respect to the central axis and a plurality of sub-regions in the plurality of main regions such that a lower surface of the main thin film is divided into a plurality of unit regions, the plurality of unit regions arranged in a plurality of columns and a plurality of rows; a plurality of temperature elements respectively in the plurality of sub-regions of the main thin film and configured to apply local heat to the substrate; and a plurality of pressure elements respectively in the plurality of temperature elements and configured to apply local pressure to the main thin film.
According to some example embodiments, a polishing head may include a substrate carrier providing a plurality of fluid passages, a flexible membrane including a plurality of pressurizing chambers in fluid communication with the plurality of fluid passages and clamped to a lower portion of the substrate carrier to form the plurality of pressurizing chambers, a plurality of temperature elements configured to apply local heat the substrate, and a plurality of pressure elements configured to apply local pressure to the flexible thin membrane.
The flexible membrane may include a main thin film having a first surface in contact with the substrate and a second surface opposite to the first surface and a plurality of vertical thin films extending from the main thin film in a vertical direction to define a plurality of pressurizing chambers divided along a radial direction about a central axis. The main thin film may provide a main region where the plurality of pressurizing chambers are disposed and a plurality of sub-regions dividing the main region. The plurality of pressure elements and the plurality of temperature elements may be respectively provided on the plurality of sub-regions of the main thin film.
Accordingly, an asymmetric distribution and a flatness of the substrate may be improved through local pressure control. In addition, through direct and local temperature control, heating and cooling times may be shortened, and defects in the substrate may be prevented by decreasing solidification of the slurry. Additionally, unintentional damage to a metal layer of the substrate may be prevented by the temperature control.
Hereinafter, example embodiments will be explained in detail with reference to the accompanying drawings. Like reference numerals in the drawings denote like components, and sizes of components in the drawings may be exaggerated for convenience of explanation. In addition, embodiments to be described below are only examples, and various modifications from such embodiments may be possible. Additionally, when the terms “about” or “substantially” are used in this specification in connection with a numerical value and/or geometric terms, it is intended that the associated numerical value includes a manufacturing tolerance (e.g., ±10%) around the stated numerical value. Further, regardless of whether numerical values and/or geometric terms are modified as “about” or “substantially,” it will be understood that these values should be construed as including a manufacturing or operational tolerance (e.g., ±10%) around the stated numerical values and/or geometry.
Additionally, although the terms “first,” “second,” “third,” etc., may be used herein to describe various elements, components, regions, layers, and/or sections, these elements, components, regions, layers, and/or sections, should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or section, from another region, layer, or section. Thus, a first element, component, region, layer, or section, discussed below may be termed a second element, component, region, layer, or section, without departing from the scope of this disclosure.
Referring to
The platen 20 may be configured to rotate the polishing pad 30 at a desired speed in order to polish a substrate such as a wafer. The polishing pad 30 may be positioned on the platen 20. The platen 20 may have a disk shape. A platen driving unit 22 may be connected to the platen 20 and may include a rotation shaft driven by, e.g., a driving motor, and the platen 20 may be configured to be rotated by the rotation shaft.
The polishing pad 30 may include abrasive particles for polishing the substrate. The polishing pad 30 may include an elastic material such as polyurethane with a rough surface. The polishing pad 30 may be configured to be rotated together with the platen 20. The polishing pad 30 may be used to mechanically planarize the wafer.
The slurry supply apparatus 40 may dispense a slurry solution 42 (e.g., during a chemical mechanical polishing process) onto the polishing pad 30 through a slurry supply nozzle. The slurry solution 42 may be used to chemically planarize the wafer.
The polishing head 100 may hold the substrate and press a surface of the substrate to be polished against the polishing pad 30. The polishing head 100 may be connected to and combined with a driving shaft 212 of the polishing carrier apparatus to move the surface of the substrate onto the polishing pad 30.
The pad conditioner 50 may be provided to reduce the abrasion of the polishing pad 30. After a period of use, protuberances on the polishing pad 30 may be worn by friction between the polishing pad 30 and the substrate. The pad conditioner 50 may regenerate the rough surface of the polishing pad 30 to a certain level (e.g., with tolerance) by grinding the surface of the polishing pad 30. Accordingly, the polishing pad 30 may be used for an extended time without being replaced.
The chemical mechanical polishing apparatus may include substantially the same or similar components as a commonly used CMP apparatus except for the polishing carrier apparatus. Hereinafter, the polishing carrier apparatus will be described in detail.
The polishing carrier apparatus may be adapted to pressurize the wafer with the polishing head 100 above the platen 20, and to revolve the polishing head 100 on a central axis of the platen 20 and to rotate the polishing head 100 on a central axis of the polishing head 100. Accordingly, the polishing head 100 may adsorb the wafer and perform a rotational movement and a translational movement on the platen 20.
As illustrated in
The rotary union 210 may include a driving shaft 212 that has a plurality of gas passages 213 formed in a longitudinal direction thereof. The rotary union 210 may rotatably support the driving shaft 212 and allow fluid to flow through the gas passages 213 in a sealed state.
The driving unit 230 may include a driving motor for rotating the driving shaft 212. The driving shaft 212 may be connected to the driving motor to rotate on the driving shaft's 212 axis. A driven gear may be installed at an upper portion of the driving shaft 212, and the driving motor may rotate a driving gear, which is engaged with the driven gear, to rotate the driving shaft 212. The driving motor may be installed in the upper portion of the driving shaft 212, but it is not limited thereto. For example, the driving motor may be connected to one end portion of the driving shaft 212 to rotate the driving shaft.
The rotary union 210 may be connected to the gas supply unit 240 through gas pipes 242. The gas pipes 242 may be connected to the gas passages 213 of the driving shaft 212 of the rotary union 210.
The polishing head 100 may be fixed to the driving shaft 212 to rotate together with the driving shaft 212. The polishing head 100 may be fixed to a flange 214 of the driving shaft 212 by a clamp (not illustrated). In at least some embodiments, the polishing head 100 may be detachable.
The seal housing 220 may be installed in a lower portion of the upper module 202. The seal housing 220 may have an annular shape extending along a circumference of the flange 214 of the driving shaft 212. The seal housing 220 may be interposed between the upper module 202 and the polishing head 100. A fixing ring 160 of a fluid sealing portion 150 (see
Accordingly, the gas supply unit 240 may be configured to supply gas to the polishing head 100 for adsorption and pressurization of an object to be polished, through the gas passages 213 of the driving shaft 212. The gas supply unit 240 may supply gas to the polishing head 100 through the gas passages 213.
The gas supply unit 240 may independently supply gases having different pressures through the gas pipes 242. Accordingly, the gases having different pressures may be independently supplied to the polishing head 100 through a plurality of gas passages 213. As will be described later, the gases, which are supplied by the plurality of gas passages 213 in fluid communication with a plurality of pressure chambers of a flexible membrane 140 of the polishing head 100, may be controlled to have different pressures for each of the plurality of pressure chambers.
The polishing head 100 may be fixed to the driving shaft 212 to rotate together with the driving shaft 212. A housing 110 (see
Referring to
The substrate carrier may include a carrier body rotatable with the driving shaft 212. The flexible membrane 140 may be configured to be clamped to a lower portion of the carrier body to form a plurality of pressurizing chambers Z1, Z2, Z3, Z4, and Z5. The carrier body may include a housing 110 detachably fixed to the driving shaft 212 and a base assembly 120 installed below the housing 110 to be rotatable together with the housing 110.
The housing 110 may have a cylindrical shape. An upper end portion of the housing 110 may be fixed to the flange 214 of the driving shaft 212 by the clamp. A plurality of first passages 112 and 114 may be formed to penetrate the housing 110. Although not illustrated in the figures, sealing members such as O-rings may be provided between an upper surface of the housing 110 and a lower surface of the driving shaft 212 to form fluid-tight seals between the first passages and the gas passages.
Accordingly, the first passages 112 and 114 for pneumatic control of the polishing head 100 may be in fluid communication with the gas passages 213 formed in the driving shaft 212, respectively.
The base assembly 120 may be an assembly which is movable vertically in the lower portion of the housing 110. The base assembly 120 may include a plurality of base blocks rotatably assembled to the lower portion of the housing 110 together with the housing 110. For example, the plurality of base blocks may be stacked on each other in a vertical direction and a radial direction to have a cylindrical shape in the lower portion of the housing 110. A rolling diaphragm 122 may be clamped between an inner base block and an outer base block so that the carrier body has a gimbal structure.
The retainer ring 130 may be secured to the lower portion of the carrier body. The retainer ring 130 may be an annular ring fixed to an outer edge of the base assembly 120. when the base assembly 120 moves downward by pneumatic pressure as a working fluid, the retainer ring 130 may move downward to apply a load to the polishing pad 30.
The flexible membrane 140 may be clamped to a lower surface of the base assembly 120 within the retainer ring 130. The flexible membrane 140 may include a main thin film 142 having a disk-shape and a plurality of vertical thin films 144. The main thin film may include a first surface 142a (see
The first surface 142a of the main thin film 142 may provide a mounting surface for the wafer W. End portions of the vertical thin films 144 may be clamped to the base assembly 120 by clamp rings, such that annular or circular shaped pressurizing chambers may be formed among the vertical thin films 144. The number of the pressurizing chambers may be determined depending on the number of the vertical thin films. In some embodiments, the flexible membrane may have a five-zone type membrane for forming five pressurizing chambers, however, the examples are not limited thereto, and the number of the pressurizing chambers may vary (e.g., may be greater than and/or less than five).
In some example embodiments, a plurality of second passages 124 may be formed to penetrate the base assembly 120. The first passage 114 and the corresponding second passage 124 may be connected to each other to form a first fluid passage for supplying gas G1 into each of the pressurizing chambers Z1, Z2, Z3, Z4, and Z5. Each of the pressurizing chambers Z1, Z2, Z3, Z4 and Z5 may be in fluid communication with the gas passages 213 of the driving shaft 212 through the first fluid passage, that is, the first passages 112 and 114 of the housing 110 and the second passage 124 penetrating the base assembly 120.
Accordingly, the pressurizing chambers Z1, Z2, Z3, 74, and Z5 may be respectively in fluid communication with the plurality of gas pipes 242 of the gas supply unit 240, so that pressure in the pressurizing chambers may be independently controlled. At least one of the pressurizing chambers may be evacuated to provide a vacuum atmosphere to vacuum adsorb the wafer W. At least one of the pressurizing chambers may be filled with a predetermined amount of gas to pressurize the wafer W.
The plurality of first temperature elements 300 and the plurality of first pressure elements 400 may be provided under the flexible membrane 140 to apply local heat and pressure to the substrate.
In some example embodiments, the fluid sealing portion 150 may be a mechanical seal configured to seal and flow fluid in a direction perpendicular to a rotation axis of the base assembly 120 when the base assembly 120 of the carrier body rotates. The fluid sealing portion 150 may include a rotation ring 170 rotating with the carrier body on an upper surface of the carrier body, and a fixing ring 160 fixedly supported on the rotation ring 170 to slidably move to be in close contact with the rotation ring 170.
The fixing ring 160 and the rotation ring 170 may maintain fluid sealing while sliding in close contact with each other. The fixing ring 160 and the rotation ring 170, which have surfaces facing each other, may include a low friction material such as silicon carbide. The rotation ring 170 may be fixedly coupled to an upper surface of the base assembly 120 outside the housing 110. The rotation ring 170 may include at least a portion of an upper base block of the base assembly 120.
Hereinafter, examples of the flexible membrane will be described in detail.
Referring to
The plurality of vertical thin films 144 may have a plurality of ring-shaped walls that extend to be concentric to each other when viewed in a plan view. The plurality of vertical thin films 144 may be disposed on the second surface 142b of the main thin film 142 and be spaced apart from each other in a radial direction.
The flexible membrane 140 may include first to fifth pressurizing chambers Z1, Z2, Z3, Z4, and Z5 that are defined by the main thin film 142 and the plurality of vertical thin films 144. For example, a lower surface of the first to fifth pressurizing chambers Z1, Z2, Z3, Z4, and Z5 may be defined by the main thin film 142 and the plurality of vertical thin films 144 may divide the first to fifth pressurizing chambers Z1, Z2, Z3, Z4, and Z5. The main thin film 142 may include a plurality of main regions and a plurality of sub-regions that subdivide the plurality of main regions, respectively.
The first to fifth pressurizing chambers Z1, Z2, Z3, Z4, and Z5 may be respectively provided on the first to fifth main regions AR1, AR2, AR3, AR4, and AR5 of the main thin film 142 that are divided by the plurality of vertical thin films 144.
The first to fifth main regions ARI, AR2, AR3, AR4, and AR5 may be regions divided along the circumferential direction with respect to a central axis. For example, the first to fifth main regions AR1, AR2, AR3, AR4, and AR5 may be regions separated by the plurality of vertical thin films 144 to be concentric with a center O of the first surface 142a of the main thin film 142. For example, outermost radii of the first to fifth main regions AR1, AR2, AR3, AR4, and AR5 may gradually increase from the origin O.
The first to fifth main regions ARI, AR2, AR3, AR4, and AR5 may include the plurality of sub-regions that respectively subdivide the first to fifth main regions AR1, AR2, AR3, AR4, and AR5.
The plurality of sub-regions may be provided in each of the first to fifth main regions AR1, AR2, AR3, AR4, and AR5, and sequentially arranged in a circumferential direction with respect to the central axis. For example, the first to fifth main regions AR1, AR2, AR3, AR4, and AR5 may include a plurality of sub-regions divided by at least one extension line passing through the center O of the first surface 142a of the main thin film 142. For example, each of the first to fifth main regions AR1, AR2, AR3, AR4, and AR5 may be divided into four sub-regions by a first extension line ELI and a second extension line EL2 passing through the center O of the first surface 142a of the main thin film 142.
For example, the first main region ARI may include a plurality of first sub-regions S11, S12, S13, and S14, and the second main region AR2 may include a plurality of second sub-regions S21, S22, S23, and S24, and the third main region AR3 may include a plurality of third sub-regions S31, S32, S33, S34, and the fourth main region AR4 may include a plurality of fourth sub-regions S41, S42, S43, and S44, and the fifth main region AR5 may include a plurality of fifth sub-regions S51, S52, S53, and S54.
For example, the plurality of sub-regions may have a same central angle. For example, portions S14, S24, S34, S44, and S54 of the plurality of sub-regions having a same central angle CD may be sequentially disposed in the radial direction.
For example, the sizes of a plurality of sub-regions included in a single main region may be the same. Alternatively, although not illustrated in the figures, the sizes of the plurality of sub-regions may be different.
The flexible membrane 140 may include a plurality of cavities CA provided on each of the plurality of sub-regions. The plurality of cavities CA may be a plurality of hollow spaces provided in and/or defined by the main thin film 142.
In some example embodiments, the plurality of first temperature elements 300 may be disposed within the plurality of cavities CA of the main thin film 142 on each of the sub-regions. The temperature element may include a thermoelectric element. The thermoelectric element may be a Peltier element configured to change temperature based on Peltier effect, which controls amount of heat generated or absorbed by applying a current to a metal. For example, the thermoelectric element may include a plurality of flexible polymers, a plurality of electrodes, and a plurality of n-type and p-type semiconductors, and may absorb and generate heat when a current is applied. For example, the plurality of electrodes may include a metal material to which current is applied. Additionally, the plurality of flexible polymers may include an insulating material.
For example, each of the plurality of first temperature elements 300 may include a plurality of flexible structures 310 including a flexible polymer, and a plurality of first electrodes 320 disposed on the plurality of flexible structures 310, and a plurality of semiconductors 330 respectively provided between the plurality of first electrodes 320. The plurality of flexible structures 310 may include first and second flexible plates 311 and 313 respectively provided on and/or between the first surface 142a and the second surface 142b of the main thin film 142, the first and second flexible plates 311 and 313 including a flexible polymer. For example, the plurality of first temperature elements 300 may each of a lower surface 300a disposed to face the first surface 142a of the main thin film 142. The plurality of first electrodes 320 may include a plurality of first metal plates 321 and 323 provided on the first flexible plate 312 and a second metal plate 325 provided on the second flexible plate 313. The plurality of semiconductors 330 may include a P-type semiconductor 331 and an N-type semiconductor 333. In some embodiments, the P-type semiconductor 331 and the N-type semiconductor 333 may have different charge carrier densities. The plurality of semiconductors 330 may also be referred to as semiconductor elements, a thermoelectric element, and/or as a Peltier element. The plurality of first temperature elements 300 may be provided in the plurality of cavities CA of the main thin film 142, respectively. For example, the plurality of first temperature elements 300 may be provided on the sub-regions S11 and S13 of the first surface 142a of the main thin film 142, respectively.
Accordingly, through the plurality of first temperature elements 300, the flexible membrane may locally absorb or generate heat on the sub-regions subdividing the main regions AR1, AR2, AR3, AR4, and AR5. For example, a wafer adsorbed on the first surface 142a of the main thin film 142 may be directly heated and/or cooled through the plurality of first temperature elements 300.
In some example embodiments, the flexible membrane 140 may have a plurality of recesses R on the second surface 142b of the main thin film 142. The plurality of recesses R may be provided on each of the plurality of first temperature elements 300. The plurality of recesses R may be passages through which fluid is capable of moving to cool the plurality of first temperature elements 300. The fluid may be referred to as a thermal regulation fluid, and may include, e.g., a gas (e.g., nitrogen, air, etc.) and/or a non-conductive liquid.
In some example embodiments, a plurality of first pressure elements 400 may be respectively provided on the plurality of first temperature elements 300 in the plurality of cavities CA of the main thin film 142. For example, each of the plurality of first pressure elements 400 may have a first (or lower) surface 400a and a second (or upper) surface 400b, and may be arranged such that the first surface 400a is facing a corresponding second surface 300b of a corresponding one of the plurality of first temperature elements 300. The pressure element may include a converse piezoelectric element. The converse piezoelectric element may be an element that generates a current when pressure is applied to an object containing a specific material. For example, the converse piezoelectric element may include a plurality of electrodes and a piezoelectric polymer provided between the plurality of electrodes, and may be compressed or expanded when a current is applied. For example, the plurality of electrodes may include a metal material to which current is applied.
Each of the plurality of first pressure elements 400 may include a plurality of second electrodes 410 and a piezoelectric structure 420 provided between the plurality of second electrodes 410 and including, e.g., a piezoelectric polymer. The piezoelectric structure 420 may be configured to expand and/or contract based on, e.g., the application and/or directionality of a current and/or voltage across the piezoelectric structure 420.
The plurality of first pressure elements 400 may be respectively provided in a plurality of cavities CA of the main thin film 142. For example, the plurality of first pressure elements 400 may be provided in sub-regions S11 and S13 of the first surface 142a of the main thin film 142, respectively.
Accordingly, through the plurality of first pressure elements 400, the flexible thin membrane may apply local pressure to the sub-regions subdividing the main regions AR1, AR2, AR3, AR4, and AR5.
Each of the plurality of first pressure elements 400 may have a first width W1, and each of the plurality of first temperature elements 300 may have a second width W2. For example, the first width and the second width may be the same and/or substantially similar.
In some example embodiments, the flexible membrane 140 may further include a plurality of third electrodes ED and a plurality of wires EW respectively providing electric connection between the plurality of third electrodes provided on the same sub-region. The plurality of third electrodes may be electrically connected to the pressure element and the temperature element, respectively.
For example, the plurality of electrodes ED may be arranged along the first extension line EL1 and/or the second extension line EL2 that pass through the center O of the first surface 142a of the main thin film 142. Although the plurality of wires EW and the plurality of electrodes ED are illustrated as being provided on the first surface 142a of the main thin film 142, the examples are not be limited thereto this, for example, the plurality of wires EW and the plurality of electrodes ED may be provided in the main thin film 142.
As mentioned above, the polishing head of the chemical mechanical polishing apparatus may include the substrate carrier having the plurality of fluid passages, the flexible membrane 140 including the plurality of pressurizing chambers in fluid communication with the plurality of fluid passages and clamped to a lower portion of the substrate carrier to form the plurality of pressurizing chambers, the plurality of first temperature elements 300 configured to apply local heat to the substrate, and the plurality of first pressure elements 400 configured to apply local pressure to the flexible membrane.
The flexible membrane 140 may provide the main thin film 142 having the first surface to be in contact with the substrate and a second surface opposite to the first surface and the plurality of vertical thin films 144 extending from the main thin film in the vertical direction to define the plurality of pressurizing chambers that are divided along a circumferential direction about a central axis of the main thin film 142. The main thin film 142 may include the main region where the plurality of pressurizing chambers are disposed and the plurality of sub-regions dividing the main region. The plurality of first pressure elements 400 and the plurality of first temperature elements 300 may be respectively provided on the plurality of sub-regions of the main thin film.
Accordingly, an asymmetric distribution and a flatness of the substrate may be improved through local pressure control. In addition, through direct and local temperature control, heating and cooling times may be shortened, and defects in the substrate may be prevented and/or reduced by decreasing solidification of the slurry. Additionally, unintentional damage to a metal layer of the substrate may be prevented and/or reduced by the temperature control.
Hereinafter, a flexible membrane in accordance with some example embodiments will be described.
The flexible membrane may be substantially the same or similar to the flexible membrane 140 described with reference to
Referring to
The plurality of vertical thin films 144 (see
The sub-region US may be a region in which the plurality of first pressure elements 400 and the plurality of first temperature elements 300 are respectively provided. The plurality of first temperature elements 300 and the plurality of first pressure elements 400 may be provided on the sub-regions US in a plurality of cavities CA of the main thin film 142, respectively.
The sub-region US may include a plurality of unit regions of the same and/or substantially similar size, arranged in a plurality of columns and a plurality of rows. The sub-region may include the plurality of unit regions subdividing the plurality of main regions AR1, AR2, AR3, AR4, and AR5 of the main thin film 142, and may be evenly distributed throughout the first surface 142a of the main thin film 142. In at least some embodiments, some of the plurality of unit regions may be shared by and/or extend over the boundaries between the plurality of main regions AR1, AR2, AR3, AR4, and AR5.
For example, the sub-region US may include the plurality of unit regions sequentially arranged in a first horizontal direction (X direction) and a second horizontal direction (Y direction) perpendicular to the first horizontal direction (X direction). For example, the unit region may have a rectangular shape when viewed from a plan view.
The sub-region US may include a plurality of third electrodes ED configured to electrically connect each of the plurality of first pressure elements 400 and each of the plurality of first temperature elements 300 respectively provided on the plurality of unit regions.
Hereinafter, a pressure element and a temperature element in accordance with some example embodiments will be described.
In some example embodiments, a plurality of second temperature elements 301 may be provided on each of the sub-regions in the plurality of cavities CA of the main thin film 142. For example, a plurality of second temperature elements 301 may be provided on the sub-regions S11 and S13 of the first surface 142a in the main thin film 142, respectively.
Therefore, through the plurality of second temperature elements 301, the flexible membrane may locally absorb and/or generate heat on the sub-regions subdividing the main regions AR1, AR2, AR3, AR4, and AR5. For example, the wafer adsorbed on the first surface 142a of the main thin film 142 may be directly heated and/or cooled through the plurality of second temperature elements 301.
The temperature element may include a thermoelectric element. The thermoelectric element may be, e.g., a Peltier element based on Peltier effect, which controls an amount of heat generated or absorbed by applying a current to, e.g., a Peltier element. For example, the thermoelectric element may include a plurality of flexible polymers, a plurality of electrodes, and a plurality of n-type and p-type semiconductors, and may be configured to absorb and generate heat in response to the application and/or direction of an applied current. For example, the plurality of electrodes may include a metal material to which current is applied. Additionally, the plurality of flexible polymers may include an insulating material.
In some example embodiments, the plurality of second pressure elements 401 may be respectively provided in the plurality of cavities CA of the main thin film 142 of the flexible membrane 140. For example, the plurality of second pressure elements 401 may be respectively provided on the plurality of second temperature elements 301 provided on the sub-regions S11 and S13 of the first surface 142a within the main thin film 142.
The plurality of second pressure elements 401 may each include a converse piezoelectric element. The converse piezoelectric element may be an element that generates a current when pressure is applied to an object containing a piezoelectric material and/or which may be compressed or expanded when a current is applied. For example, the converse piezoelectric element may include a plurality of electrodes and a piezoelectric polymer provided between the plurality of electrodes, and may be compressed or expanded when a current is applied and to generate a current when compressed and/or expanded. For example, the plurality of electrodes may include a metal material to apply current.
Accordingly, through the plurality of second pressure elements 401, the flexible membrane may apply local pressure to sub-regions subdividing the main regions AR1, AR2, AR3, AR4, and AR5.
The plurality of second temperature elements 301 may include a base portion BP provided under the plurality of second pressure elements 401 and disposed adjacent to the first surface 142a of the main thin film 142, a pair of first extension portions EP1 and EP2 surrounding side portions of each of the plurality of second pressure elements 401 and extending in the vertical direction (Z direction) from the base portion toward the plurality of recesses R, and a pair of second extension portions EP3 and EP4 disposed on the plurality of second pressure elements 401 and extending from the pair of first extension portions toward a central extension line ML of each of the plurality of recesses R.
The plurality of second temperature elements 301 may provide a plurality of openings as a receiving portion RP defined by inner surfaces of the base portion BP, the pair of first extension portions EP1 and EP2, and the pair of second extension parts EP3 and EP4. The pressure element may be provided within the plurality of openings as a receiving portion RP.
Each of the pair of second extension portions EP3 and EP4 may have end surfaces ES1 and ES2 facing each other and are spaced apart in the horizontal direction. The pair of second extension portions EP3 and EP4 may be provided on the plurality of first pressure elements 400, and the end surfaces ES1 and ES2 may define the plurality of openings RP.
A contact surface of each of the plurality of second pressure elements 401 and each of the plurality of second temperature elements 301 provided on each of the plurality of second pressure elements 401 may have a third width W3. The third width W3 may be smaller than the second width W2 of the plurality of second temperature elements 301.
In some example embodiments, the flexible membrane 140 may have a plurality of recesses R on the second surface 142b of the main thin film 142. The plurality of recesses R may be provided on each of the plurality of second temperature elements 301. The plurality of recesses R may be a passage through which fluid moves to cool the plurality of second temperature elements 301.
The plurality of recesses R may be aligned with the plurality of openings RP of the plurality of second temperature elements 301 along and the central extension line ML.
For example, the fluid introduced through the plurality of recesses R may pass through the opening OP of the plurality of second temperature elements 301 to be in contact with outer and inner surfaces of the plurality of second temperature elements 301, so cooling the outer and inner surfaces.
The above-described polishing head may be used in a chemical mechanical polishing process. A semiconductor device formed by the chemical mechanical polishing process may be used in various types of systems, such as computing systems. The semiconductor device may include fin field effect transistor (finFET), dynamic random-access memory (DRAM), NAND, etc. The system may be applied to computers, portable computers, laptop computers, personal digital assistants, tablets, mobile phones, digital music players, etc.
The foregoing is illustrative of some example embodiments and is not to be construed as limiting thereof. Although a few example embodiments have been described, those skilled in the art will readily appreciate that many modifications are possible in the example embodiments without materially departing from the novel teachings and advantages of the present invention. Accordingly, all such modifications are intended to be included within the scope of the example embodiments as defined in the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2023-0148786 | Nov 2023 | KR | national |
