This application generally relates to a semiconductor processing apparatus, and more specifically, to a semiconductor processing apparatus with a tunable radio frequency loop.
Plasma processing is used in the manufacturing of integrated circuits, photo masks, plasma display, and solar technology. In the manufacturing of an integrated circuit, a wafer is processed by a plasma cavity through, for example, etching, plasma enhanced chemical vapor deposition (PECVD), or plasma enhanced physical vapor deposition (PEPVD). For a more miniature integrated circuit, the control of processing parameters such as plasma energy spectrum, plasma energy radial distribution, plasma density, and plasma density radial distribution needs to be more precise. Especially, the plasma density determines the deposition rate and etching rate on a wafer surface. The plasma density radial distribution and the plasma energy radial distribution affect the uniformity of deposition and etching more significantly. A known semiconductor processing apparatus is provided with an upper electrode and a lower electrode, between which plasma can be generated. However, with the known configuration, it is still not easy to implement precise control, or even the freedom of plasma adjustment is limited.
Therefore, it is necessary to develop a semiconductor processing apparatus or radio frequency component that can provide different radio frequency control strategies to meet the freedom of the process design.
In an aspect, this application provides a plate for a semiconductor processing apparatus, the plate including a first electrode and a second electrode, where the first electrode is selectively coupled to a first ground terminal via a first switch, the second electrode is selectively coupled to a second ground terminal via a second switch, and the first electrode and the second electrode are electrically isolated from each other.
In some embodiments, the plate further includes a carrying surface for carrying a wafer, where the first electrode and the second electrode are located below the carrying surface.
In some embodiments, the first electrode is defined by a first radius, and the second electrode is defined by a second radius and a third radius, and the third radius is greater than the first radius and the second radius. The first electrode and the second electrode are located in the same plane or in different planes.
In some embodiments, the first electrode is defined by a first radius, the second lower electrode is defined by a second radius, and the first electrode and the second electrode are located in different planes. According to an embodiment of this application, the first radius and the second radius are approximately equal.
In some embodiments, the first electrode and the second electrode are arranged concentrically. In some other embodiments, at least one of the first electrode and the second electrode is a block in a circular electrode or an annular electrode, and the circular electrode or the annular electrode includes a plurality of blocks.
In some embodiments, at least one of the first electrode and the second electrode includes a mesh structure.
In another aspect, this application provides a semiconductor processing apparatus, including the plate according to an embodiment of this application. The semiconductor processing apparatus further includes a second plate including a third electrode, where the third electrode is electrically coupled to a radio frequency generating and matching device.
In some embodiments, the semiconductor processing apparatus further includes: a first feedback component configured to provide a first feedback signal to the radio frequency generating and matching device based on a signal received from the first electrode; and a second feedback component configured to provide a second feedback signal to the radio frequency generating and matching device based on a signal received from the second electrode.
In still another aspect, this application provides a method for manufacturing a ground electrode for a semiconductor processing apparatus, the method including: providing a plate body; and forming a first electrode and a second electrode electrically isolated from each other in the plate body in the following manner: (1) sintering the first electrode and the second electrode separately into the plate body; or (2) molding at one time the first electrode and the second electrode by using a method of braiding combination and pressing them into the plate body.
In some embodiments, sintering the first electrode and the second electrode separately into the plate body includes: forming the first electrode and the second electrode in the same plane of the plate body by sintering. In some other embodiments, sintering the first electrode and the second electrode separately into the plate body includes: forming the first electrode and the second electrode in different planes of the plate body by sintering.
In yet another aspect, this application provides a method for operating the semiconductor processing apparatus according to an embodiment of this application, the method including: for first processing, controlling the first switch to couple the first electrode to the first ground terminal; and for second processing, controlling the second switch to couple the second electrode to the second ground terminal. In some embodiments, the method further includes: for third processing, controlling the first switch and the second switch to couple the first electrode and the second electrode respectively to the first ground terminal and the second ground terminal.
Details of one or more examples of this application are set forth in the following drawings and description. Other features, objectives, and advantages become obvious according to the description, drawings, and claims.
The following drawings are mentioned and included in the content disclosed in this specification:
By convention, the drawings are only used to illustrate non-limiting and non-exhaustive examples. The components in the drawings do not have to be actual sizes, and the features illustrated in the drawings may not be drawn to scale. Therefore, for clarity, the size of the features can be enlarged or reduced as required. In addition, for clarity, the embodiments illustrated in the drawings may be simplified. Therefore, the drawings may not illustrate all components of a given device or apparatus. Finally, the same reference numbers may be used throughout the specification and drawings to indicate the same features.
Hereinafter, the present invention will be described more fully with reference to the drawings, and specific exemplary embodiments are shown through examples. However, the claimed subject matter can be implemented in many different forms. Therefore, the construction of the claimed subject matter covered or applied for is not limited to any exemplary specific embodiments disclosed in this specification; and the exemplary specific embodiments are only examples. Likewise, the present invention aims to provide a properly broad category for the claimed subject matter that is applied for or covered. In addition, for example, the claimed subject matter can be embodied as a method, apparatus, or system. Therefore, specific embodiments may take the form of, for example, hardware, software, firmware, or any combination of these (known not as software).
The term “in one embodiment” or “according to an embodiment” used in this specification does not necessarily refer to the same specific embodiment, nor does it mean that the claimed technical solution needs to include all the features described in the embodiment. In this specification, the use of “in other (some/given) embodiments” or “according to other (some/given) embodiments” used herein does not necessarily refer to different specific embodiments. The objective is, for example, that the claimed subject matter includes all or part of a combination of exemplary embodiments.
The terms “including” and “comprising” in this specification are used in an open-ended manner, and therefore should be interpreted as “including, but not limited to . . . ” The term “coupled” in this specification should be understood to encompass “directly connected” and “connected via one or more intermediate components.” The meanings of “upper” and “lower” in this specification are not limited to the relationship directly presented by the diagrams, and should include descriptions with clear correspondence, such as “left” and “right”, or the opposite of “upper” and “lower.” The term “wafer” in this specification should be understood as being interchangeable with terms such as “die,” “chip,” “substrate,” “silicon wafer,” “substrate base” and the like. This specification uses some terms to refer to specific system components. As those skilled in the art understand, different companies may use different names to refer to the system components.
In the example in
In some embodiments, the first electrode 101 may be an upper electrode, and the second electrodes 102 and 103 may be lower electrodes. In some other embodiments, the first electrode 101 may be a lower electrode, and the second electrodes 102 and 103 may be upper electrodes. Generally, the upper electrode is arranged at a top portion of the cavity. Although
The lower electrode is configured in a wafer support base. Although not shown in
Although not shown, the radio frequency generating and matching device 104 may include a radio frequency generator and a radio frequency matcher. In an embodiment, the radio frequency generator in the radio frequency generating and matching device 104 may include a low-frequency radio frequency source, a high-frequency radio frequency source, or a combination of both, and the radio frequency matcher in the radio frequency generating and matching device 104 may include a low-frequency dedicated matching network, a high-frequency dedicated matching network, or a combination of both. The matching network includes one or more capacitors, one or more inductors, and some electronic components, and detailed composition of the matching network is not described herein. According to different processing, the selection of low-frequency or high-frequency radio frequency operations is known, and details are not described herein again. The radio frequency generating and matching device 104 is configured to: receive one or more feedback signals provided by the feedback/control apparatuses 105 and 106, and adjust an output frequency of the low-frequency or high-frequency radio frequency source and/or one or more variable electronic components in the matching network, for example, variable capacitors, or other variable components in the radio frequency circuit components, so as to control features of the plasma in the chamber. In some embodiments, the radio frequency generating and matching device 104 may be configured to receive one or more feedback signals from the first electrode 101. In some other embodiments, one or more of the feedback/control apparatuses 105 and 106 do not provide a feedback signal to the radio frequency generating and matching device 104.
In addition, according to different objectives, the feedback/control apparatus in this application may be used to determine various operations associated with the second electrode(s), for example, determine whether the second electrode(s) is (are) grounded, whether to adjust the related variable electronic component(s) or the power applied to the second electrode(s).
Under the control of a control signal SC, the switch 118 selectively couples the ground electrode 112 to the ground terminal or disconnects the ground electrode from the ground terminal. The control signal SC may be based at least in part on the signal received from the ground electrode 112, or at least in part on the signal received from other ground electrode(s) or radio frequency electrode(s), or at least in part on the process requirements of the processing being or to be performed. The control signal SC may be generated by hardware or software. The method for generating a control signal based on some signals or parameters is well known to those skilled in the art, and therefore details are not described herein again. In some embodiments, an impedance network composed of components such as one or more resistors, one or more capacitors, and one or more inductors may be included between the ground electrode 112 and the ground terminal. The impedance network may provide a fixed impedance or a variable impedance in the radio frequency loop (for example, through a variable capacitor).
The configuration of the ground electrode shown in this embodiment includes a first electrode 201, a second electrode 202, and a third electrode 203. In some embodiments, the first electrode 201, the second electrode 202, and the third electrode 203 are arranged concentrically. The first electrode 201 is a circular electrode defined by a first radius R1. The second electrode 202 is defined by at least a second radius R2. The third electrode 203 is defined by at least a third radius R3. The second radius R2 is greater than the first radius R1 but less than the third radius R3. In an embodiment, the second electrode 202 is a circular electrode; and in another embodiment, the second electrode 202 may be an annular electrode defined by a first inner diameter and the second radius R2, and the first inner diameter may be greater than, equal to, or less than the first radius In an embodiment, the third electrode 203 is a circular electrode; and in another embodiment, the third electrode 203 may be another annular electrode defined by a second inner diameter and the third radius R3, and the second inner diameter may be greater than, equal to, or less than the second radius R2.
In some embodiments, the first electrode 201, the second electrode 202, and the third electrode 203 may be located at the same level (that is, in the same plane). In the embodiments, the second electrode 202 and the second electrode 203 are annular electrodes, and the inner diameter of the second electrode 202 is greater than or equal to the first radius R1, and the inner diameter of the third electrode 203 is greater than or equal to the second radius R2. In some other embodiments, the first electrode 201, the second electrode 202, and the third electrode 203 may be at different levels (that is, in different planes), and related examples are provided below. The first electrode 201, the second electrode 202, and the third electrode 203 are electrically isolated from each other (for example, an insulating material is used between the electrodes, or the electrodes are spaced apart from each other). As shown in the figure, each of the first electrode 201, the second electrode 202, and the third electrode 203 may be selectively connected to a ground terminal respectively (feedback/control apparatus(es) is (are) omitted).
In the example of
The circular electrode 210 includes blocks 212, 214, 216, and 218. The annular electrode 220 includes blocks 222, 224, 226, and 228. In some embodiments, the blocks 212, 214, 216, and 218 are electrically isolated from each other by insulating materials, and therefore may be grounded independently. Similarly, in some embodiments, the blocks 222, 224, 226, and 228 are electrically isolated from each other by insulating materials, and therefore may be grounded independently. For example, the second electrode 202 shown in
The wafer support base shown in
The first lower electrode 304 and the second lower electrode 305 are electrically coupled to a first feedback/control apparatus 306 and a second feedback/control apparatus 307 respectively. The first feedback/control apparatus 306 is configured to have an appropriate circuit composition to receive a sensed signal from the first lower electrode 304 and generate a first feedback signal accordingly. Similarly, the second feedback/control apparatus 307 is configured to have an appropriate circuit composition to receive a sensed signal from the second lower electrode 305 and generate a second feedback signal accordingly. The sensed signal is related to radio frequency power received by each lower electrode (304 or 305) from the upper electrode 302, so that the feedback signal can reflect the features of the plasma in the chamber. The first feedback/control apparatus 306 is in communication connection with the radio frequency generating and matching device 303 via a first feedback path 308, thereby providing the first feedback signal to the radio frequency generating and matching device 303. Similarly, the second feedback/control apparatus 307 is in communication connection via a second feedback path 309 and provides the second feedback signal to the radio frequency generating and matching device 303. In addition, the first feedback/control apparatus 306 and the second feedback/control apparatus 307 are further configured to be capable of selectively electrically coupling the first lower electrode 304 and the second lower electrode 305 to corresponding ground terminals. In addition, although not shown, the first feedback path 308 and the second feedback path 309 may be respectively electrically connected to low-frequency and high-frequency control parts of the radio frequency generating and matching device 303 to implement different processing corresponding to low frequency and high frequency.
The radio frequency generating and matching device 303 is configured to: receive the first feedback signal and/or the second feedback signal, and adjust the plasma based on the feedback signal. The radio frequency generating and matching device 303 may further include a controller for signal processing and outputting. In a possible embodiment, the radio frequency generator (for example, a high-frequency generator or a low-frequency generator) in the radio frequency generating and matching device 303 may adjust a radio frequency output frequency according to instructions of the controller. Alternatively, the radio frequency matcher (for example, a high-frequency matcher or a low-frequency matcher) in the radio frequency generating and matching device 303 may adjust a variable capacitance value according to instructions of the controller to obtain an appropriate matching impedance.
In some possible embodiments, the radio frequency generating and matching device 303 may further include other circuit modules, such as an impedance controller composed of a bandpass filter and/or a notch filter, which may be formed by connecting one or more capacitors, one or more inductors, and one or more variable capacitors. The impedance controller may be configured to be included in the feedback/control apparatus (306 or 307), the radio frequency generating and matching device 303, the controller, or a circuit independent of the foregoing components. One or more impedance controllers may be configured to be electrically coupled to the first lower electrode 304 or the second lower electrode 305 and/or the upper electrode 302. Accordingly, the controller controls the radio frequency generator, the radio frequency matcher and/or the impedance controller based on the first feedback signal or the second feedback signal, thereby achieving the objective of adjusting the plasma.
The ground electrodes provided in this application may have different sizes, shapes, materials, embedding depths or grid densities.
In summary, the semiconductor processing apparatus provided in this application is provided with a plate embedded with a plurality of ground electrodes electrically isolated from each other, and each of the ground electrodes is selectively coupled to a corresponding ground terminal via a switch. Therefore, according to different processing performed by the semiconductor processing apparatus, different combinations of ground electrodes may be selected to be coupled to ground terminals to form different radio frequency loops, so that the plasma density near different electrode positions can be adjusted, and the thickness of the deposited film or the uniformity of etching can then be controlled.
In step 602, for first processing performed by the semiconductor processing apparatus, the first switch is controlled to couple the first ground electrode to the first ground terminal, that is, a radio frequency loop of the first processing includes at least the first ground electrode. In step 604, for second processing performed by the semiconductor processing apparatus, the second switch is controlled to couple the second ground electrode to the second ground terminal, that is, a radio frequency loop of the second processing includes at least the second ground electrode. The method 600 may further include: for third processing, controlling the first switch and the second switch to couple the first ground electrode and the second ground electrode to the first ground terminal and the second ground terminal respectively, that is, a radio frequency loop of the third processing includes at least both the first ground electrode and the second ground electrode.
The description in this specification is provided to enable those skilled in the art to implement or use the present invention. Modifications to the present invention are readily apparent to those skilled in the art, and the general principles defined in this specification can be applied to other variations without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the examples and designs described in this specification, but is given the widest scope consistent with the principles and novel features disclosed in this specification.
Number | Date | Country | Kind |
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201910671631.9 | Jul 2019 | CN | national |
Filing Document | Filing Date | Country | Kind |
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PCT/CN2020/093782 | 6/1/2020 | WO |