Electrostatic chuck with spatially adjustable RF coupling to the wafer.
By introducing microchannels into the electromagnetic chuck of the semiconductor chip and filling the fluid with different dielectric constants, the problems of high cost of adjusting the RF current distribution and system complexity in the prior art are solved, and the adjustment of the adjustability and processing accuracy of the semiconductor chip are improved.
Patent Information
- Application Number
- JP2021562782
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2019-04-22
- Filing Date
- 2020-04-14
- Publication Date
- 2025-03-28
- Estimated Expiration
- 2040-04-14
AI Technical Summary
In the prior art, when adjusting the RF current distribution of semiconductor chips during sub-processing, there are problems of high cost and high system complexity.
Adjust the distribution of RF current by introducing microchannels into the dielectric layer of the electromagnetic chuck and using these microchannels to fill fluids with different dielectric constants, thereby achieving adjustability to the semiconductor chip.
The adjustability of the RF current distribution of semiconductor chips is achieved, reducing system cost and complexity, and improving processing accuracy.
Smart Images

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Abstract
Description
[Technical field]
[0001] <CROSS REFERENCE TO RELATED APPLICATIONS> This application claims the benefit of U.S. Provisional Application No. 62 / 836,836, filed April 22, 2019, which is incorporated herein by reference in its entirety.
[0002] The present disclosure relates generally to substrate processing systems, and more particularly to an electrostatic chuck having spatially adjustable RF coupling to a wafer. [Background technology]
[0003] The background description provided herein is intended to provide a general overview of the contents of the present disclosure. Work by the currently named inventors within the scope of what is described in this Background section, as well as aspects of the description that may not otherwise be regarded as prior art at the time of filing, are not admitted, expressly or impliedly, as prior art against the present disclosure.
[0004] A substrate processing system typically includes multiple processing chambers (also called processing modules) for performing deposition, etching, and other processing of substrates such as semiconductor wafers. Examples of processing that can be performed on a substrate include, but are not limited to, plasma-enhanced chemical vapor deposition (PECVD) processing, chemical-enhanced plasma vapor deposition (CEPVD) processing, and sputtering physical vapor deposition (PVD) processing. Further examples of processing that can be performed on a substrate include, but are not limited to, etching (e.g., chemical etching, plasma etching, reactive ion etching, etc.), and cleaning processing.
[0005] During processing, a substrate is placed on a substrate support, such as a pedestal, electrostatic chuck (ESC), etc., in a processing chamber of a substrate processing system. During deposition, a gas mixture containing one or more precursors is introduced into the processing chamber and a plasma is struck to activate a chemical reaction. During etching, a gas mixture containing an etching gas is introduced into the processing chamber and a plasma is struck to activate a chemical reaction. A computer-controlled robot typically transports the substrates from one processing chamber to another according to the order in which they are to be processed. Summary of the Invention
[0006] A substrate support assembly for supporting a semiconductor substrate in a processing chamber includes a base plate disposed within the processing chamber, a dielectric layer disposed on the base plate and supporting the semiconductor substrate, an electrode disposed within the dielectric layer along a horizontal plane, and a plurality of channels for transporting a fluid, the plurality of channels being disposed within the dielectric layer along the horizontal plane on a side of the electrode opposite the base plate.
[0007] In other features, a system includes the substrate support assembly, a power supply that provides power to the electrodes during processing of the semiconductor substrate in the processing chamber, and a fluid source that supplies and fills the plurality of channels with the fluid prior to processing of the semiconductor substrate.
[0008] In other features, a system includes the substrate support assembly, a plurality of cooling channels disposed within the base plate, a power supply that provides power to the electrodes during processing of the semiconductor substrate in the processing chamber, a coolant source for supplying a coolant to the cooling channels during the processing of the semiconductor substrate, a plurality of valves in fluid communication with the coolant source, the cooling channels, and the plurality of channels, and a controller that controls the plurality of valves to supply the coolant from the coolant source to the cooling channels and to supply the coolant to a first level as the fluid for filling the plurality of channels prior to performing a first process on the semiconductor substrate.
[0009] In other features, the controller is further configured to drain the coolant from the plurality of channels to a second level after performing the first process and before performing a second process on the semiconductor substrate.
[0010] In other features, the first level indicates that the plurality of channels are completely filled with the coolant and the second level indicates that the plurality of channels are completely empty.
[0011] In other features, the system includes the substrate support assembly, a power supply that provides power to the electrodes during processing of the semiconductor substrate in the processing chamber, a fluid source that supplies the fluid, a plurality of valves in fluid communication with the fluid source and the plurality of channels, and a controller that controls the plurality of valves to fill the plurality of channels with the fluid to a first level before performing a first process on the semiconductor substrate.
[0012] In other features, the controller is further configured to drain the fluid from the plurality of channels to a second level after performing the first process and before performing a second process on the semiconductor substrate.
[0013] In other features, the first level indicates that the plurality of channels are completely filled with the fluid and the second level indicates that the plurality of channels are completely empty.
[0014] In other features, a system includes the substrate support assembly, a power supply that provides power to the electrodes during processing of the semiconductor substrate in the processing chamber, a fluid source that supplies the fluid, a heater associated with the fluid source, and a controller that provides power to the heater and fills the plurality of channels with the fluid to a first level prior to performing a first process on the semiconductor substrate.
[0015] In other features, the controller is further configured to vary the power supplied to the heater to remove the fluid from the multiple channels to a second level after performing the first process and before performing a second process on the semiconductor substrate.
[0016] In other features, the first level indicates that the plurality of channels are completely filled with the fluid and the second level indicates that the plurality of channels are completely empty.
[0017] In other features, a system includes the substrate support assembly, a power supply that provides power to the electrodes during processing of the semiconductor substrate in the processing chamber, a first fluid source, a second fluid source for a second fluid, a plurality of valves in fluid communication with the first and second fluid sources and the plurality of channels, and a controller that controls the plurality of valves to fill the plurality of channels with the fluid to a first level before performing a first process on the semiconductor substrate, drain the fluid from the plurality of channels after performing the first process, and fill the plurality of channels with the second fluid to a second level before performing a second process on the semiconductor substrate.
[0018] In another feature, the first level is equal to the second level.
[0019] In other features, the first level indicates that the plurality of channels are completely filled with the fluid and the second level indicates that the plurality of channels are completely filled with the second fluid; the first level indicates that the plurality of channels are completely filled with the fluid and the second level indicates that the plurality of channels are partially filled with the second fluid; the first level indicates that the plurality of channels are partially filled with the fluid and the second level indicates that the plurality of channels are completely filled with the second fluid; or the first level indicates that the plurality of channels are partially filled with the fluid and the second level indicates that the plurality of channels are partially filled with the second fluid.
[0020] In other features, the system includes the substrate support assembly, a second plurality of channels disposed in the dielectric layer along the horizontal plane on the side of the electrode opposite the base plate, a power source for providing power to the electrode during processing of the semiconductor substrate in the processing chamber, a first fluid source, a second fluid source for a second fluid, a plurality of valves in fluid communication with the first and second fluid sources, the plurality of channels, and the second plurality of channels, and a controller for controlling the plurality of valves to fill the plurality of channels with the fluid to a first level before performing a process on the semiconductor substrate and to fill the second plurality of channels with the second fluid to a second level before performing the process on the semiconductor substrate.
[0021] In another feature, the first level is equal to the second level.
[0022] In other features, the first level indicates that the plurality of channels are completely filled with the fluid and the second level indicates that the second plurality of channels are completely filled with the second fluid; the first level indicates that the plurality of channels are completely filled with the fluid and the second level indicates that the second plurality of channels are partially filled with the second fluid; the first level indicates that the plurality of channels are partially filled with the fluid and the second level indicates that the second plurality of channels are completely filled with the second fluid; or the first level indicates that the plurality of channels are partially filled with the fluid and the second level indicates that the second plurality of channels are partially filled with the second fluid.
[0023] In other features, a system includes the substrate support assembly, a second plurality of channels disposed in the dielectric layer along the horizontal plane on the side of the electrode opposite the base plate, a power source for providing power to the electrode during processing of the semiconductor substrate in the processing chamber, a first fluid source, a second fluid source for a second fluid, a plurality of valves in fluid communication with the first and second fluid sources, the plurality of channels, and the second plurality of channels, and a controller for controlling the plurality of valves to fill the plurality of channels with the fluid to a first level while the second plurality of channels are empty before performing a first process on the semiconductor substrate, drain the fluid from the plurality of channels after performing the first process, and fill the second plurality of channels with the second fluid to a second level before performing a second process on the semiconductor substrate.
[0024] In another feature, the first level is equal to the second level.
[0025] In other features, the first level indicates that the plurality of channels are completely filled with the fluid and the second level indicates that the second plurality of channels are completely filled with the second fluid; the first level indicates that the plurality of channels are completely filled with the fluid and the second level indicates that the second plurality of channels are partially filled with the second fluid; the first level indicates that the plurality of channels are partially filled with the fluid and the second level indicates that the second plurality of channels are completely filled with the second fluid; or the first level indicates that the plurality of channels are partially filled with the fluid and the second level indicates that the second plurality of channels are partially filled with the second fluid.
[0026] In another feature, the plurality of channels are disposed within an annular region of the dielectric layer.
[0027] In other features, the substrate support assembly further includes a second plurality of channels disposed in the dielectric layer along the horizontal plane on the side of the electrode opposite the base plate, the plurality of channels disposed in a first annular region of the dielectric layer, the second plurality of channels disposed in a second annular region of the dielectric layer, the first and second annular regions having first and second areas, respectively.
[0028] In another feature, the plurality of channels are disposed within a sectoral region of the dielectric layer.
[0029] In other features, the substrate support assembly further includes a second plurality of channels disposed in the dielectric layer on the side of the electrode opposite the base plate and along the horizontal plane, the plurality of channels disposed in a first sector of the dielectric layer, the second plurality of channels disposed in a second sector of the dielectric layer, the first and second sectors having first and second areas, respectively.
[0030] In another feature, the plurality of channels are serpentine in shape.
[0031] In another feature, the plurality of channels are formed from a porous material.
[0032] In another feature, the plurality of channels comprises a plurality of serially connected serpentine portions.
[0033] In other features, the plurality of channels are disposed in a manifold within the dielectric layer and include a plurality of serpentine portions connected in parallel within the manifold.
[0034] In other features, the plurality of channels are formed by disposing two annular grooves in the dielectric layer and disposing a plurality of grooves radially connecting the two annular grooves, each of the plurality of grooves being smaller than the two annular grooves.
[0035] In other features, a system includes the substrate support assembly, a radio frequency power supply that supplies radio frequency power to the electrode during processing of the semiconductor substrate in the processing chamber, a DC power supply that supplies DC power to the electrode during the processing of the semiconductor substrate, and a fluid source that supplies and fills the plurality of channels with the fluid prior to the processing of the semiconductor substrate.
[0036] In other features, the system includes the substrate support assembly, a second electrode disposed in the dielectric layer along the horizontal plane on an opposite side of the plurality of channels from the electrode, a radio frequency power source that supplies radio frequency power to the electrode during processing of the semiconductor substrate in the processing chamber, a DC power source that supplies DC power to the second electrode during the processing of the semiconductor substrate, and a fluid source that supplies and fills the plurality of channels with the fluid prior to the processing of the semiconductor substrate.
[0037] In other features, the second electrode includes a first annular segment and a second annular segment, and the plurality of channels are disposed within an annular region of the dielectric layer beneath the first annular segment.
[0038] In other features, the second electrode includes a first annular segment and a second annular segment, the plurality of channels being disposed within an annular region of the dielectric layer below the first annular segment, and a portion of the dielectric layer separating the second electrode from the plurality of channels.
[0039] In other features, the second electrode includes an outer electrode and an inner electrode, the outer electrode includes a first annular segment and a second annular segment, the plurality of channels are disposed within an annular region of the dielectric layer below the first annular segment, a portion of the dielectric layer separating the second electrode from the plurality of channels, and the DC power source supplies the DC power to the first annular segment through a first resistor, to the second annular segment through a second resistor, and to the inner electrode through a third resistor.
[0040] In other features, the fluid comprises a liquid, a gas, air, a fluorinated liquid, or a liquid metal selected from the group consisting of mercury and an alloy containing bismuth, antimony, gallium, and / or indium.
[0041] Further scope of applicability of the present disclosure will become apparent from the detailed description, claims, and drawings. The detailed description and specific examples are for purposes of illustration only and are not intended to limit the scope of the present disclosure. [Brief description of the drawings]
[0042] The present disclosure will become more clearly understood from the detailed description and the accompanying drawings set forth below.
[0043] [Figure 1A]FIG. 1A is a functional block diagram of a substrate processing system including a processing chamber that uses inductively coupled plasma in etching substrates such as semiconductor wafers.
[0044] [Figure 1B] FIG. 1B is a functional block diagram of a substrate processing system including a processing chamber.
[0045] [Diagram 2] FIG. 2 is a simplified schematic diagram of an electrostatic chuck (ESC) used in the processing chamber of the substrate processing system of FIG.
[0046] [Diagram 3] FIG. 3 is a simplified schematic diagram of an ESC with microchannels disposed within the ceramic layers of the ESC. [Figure 4] FIG. 4 is a simplified schematic diagram of an ESC with microchannels disposed within the ceramic layers of the ESC.
[0047] [Diagram 5] FIG. 5 shows example geometries by which microchannels can be placed within an ESC. [Figure 6] FIG. 6 shows example geometries by which microchannels can be placed within an ESC.
[0048] [Figure 7] FIG. 7 shows an example of an apparatus for filling and emptying a microchannel. [Figure 8] FIG. 8 shows an example of an apparatus for filling and emptying a microchannel. [Figure 9] FIG. 9 shows an example of an apparatus for filling and emptying a microchannel. [Figure 10] FIG. 10 shows an example of an apparatus for filling and emptying a microchannel.
[0049] [Figure 11]FIG. 11 is a diagram showing the configuration and layout of the microchannels. [Figure 12] FIG. 12 is a diagram showing the configuration and layout of the microchannels. [Figure 13] FIG. 13 is a diagram showing the configuration and layout of the microchannels. [Figure 14] FIG. 14 shows the configuration and layout of the microchannels. [Figure 15] FIG. 15 shows the configuration and layout of the microchannels.
[0050] [Figure 16] FIG. 16 shows an example of the configuration of an ESC equipped with a microchannel. [Figure 17] FIG. 17 shows an example of the configuration of an ESC equipped with a microchannel. [Figure 18] FIG. 18 shows an example of the configuration of an ESC equipped with a microchannel. [Figure 19] FIG. 19 shows an example of the configuration of an ESC equipped with a microchannel.
[0051] [Figure 20] FIG. 20 shows an example of a system for supplying power to the clamping electrodes of an ESC with microchannels.
[0052] In the drawings, reference numbers may be reused to represent similar and / or identical elements. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0053] In some etching processes, it is required to have an adjustable etch rate of a semiconductor wafer (hereinafter referred to as the wafer) from the center to the edge of the wafer. To achieve an adjustable etch rate, the RF power delivered to the wafer must be adjustable from the center to the edge of the wafer. In some applications, a dual feed electrostatic chuck is used to focus the RF power to separate concentric zones of the wafer by a splitter. However, this approach has several drawbacks, such as the cost and complexity of the RF delivery system.
[0054] In contrast, the disclosed system and method delivers adjustable RF power to the wafer using a single RF feed. Specifically, RF current flow to the wafer depends on the coupling between the RF electrode and the wafer, and the RF current is proportional to the effective dielectric constant of the material between the RF electrode and the wafer. Thus, by changing the dielectric constant of the material between the RF electrode and the wafer, the RF current to the wafer can be changed.
[0055] According to the present disclosure, the effective dielectric constant of the material between the RF electrode and the wafer can be changed by providing microchannels in the material between the RF electrode and the wafer. The microchannels can be filled with air or a medium having a higher dielectric constant than air. For example, the microchannels may be filled with a coolant supplied to an electrostatic chuck (ESC). However, typical coolants include fluorinated liquids that have a relatively low dielectric constant. Therefore, the microchannels may be filled with other materials, including liquid metals.
[0056] These and other features of the present disclosure are described in detail below, including various configurations and layouts of the microchannels, and various methods of filling and emptying the microchannels. The teachings of the present disclosure are not limited to etching processes, but are also applicable to deposition processes, such as, for example, depositing a dielectric layer on a wafer.
[0057] This disclosure is organized as follows. First, an example of a processing chamber for processing a wafer is shown in and described with reference to FIGS. 1A and 1B. Simplified schematic diagrams of an ESC with and without a microchannel are shown in and described with reference to FIGS. 2 to 4. Examples of geometries for enabling a microchannel to be located within an ESC are shown in and described with reference to FIGS. 5 and 6. Various examples of devices for filling and emptying a microchannel are shown in and described with reference to FIGS. 7 to 10. Various configurations and layouts of a microchannel are shown in and described with reference to FIGS. 11 to 15. Various configuration examples of an ESC with a microchannel are shown in and described with reference to FIGS. 16 to 19. An example of a system for supplying power to a clamping electrode of an ESC with a microchannel is shown in and described with reference to FIG. 20.
[0058] FIG. 1A illustrates an example of a substrate processing system 10 according to the present disclosure. The substrate processing system 10 includes a coil driver circuit 11. In some examples, the coil driver circuit 11 includes an RF source 12, a pulse circuit 14, and a tuning circuit (i.e., matching circuit) 13. The pulse circuit 14 controls a transformer-coupled plasma (TCP) envelope of the RF signal generated by the RF source 12, and varies the duty cycle of the TCP envelope between 1% and 99% during operation. As can be appreciated, the pulse circuit 14 and the RF source 12 may be combined or may be separate components.
[0059] The tuning circuit 13 may be directly connected to the induction coil 16. Although the substrate processing system 10 uses a single coil, some substrate processing systems use multiple coils (e.g., an inner coil and an outer coil). The tuning circuit 13 tunes (adjusts) the output of the RF source 12 to a desired frequency and / or a desired phase and matches the impedance of the coil 16.
[0060] The dielectric window 24 is disposed along an upper surface of the processing chamber 28. The processing chamber 28 further includes a substrate support (or pedestal) 32 for supporting a substrate 34. The substrate support 32 may include an electrostatic chuck (ESC), a mechanical chuck, or other types of chucks. A process gas is supplied to the processing chamber 28, and a plasma 40 is generated inside the processing chamber 28. The plasma 40 etches the exposed surface of the substrate 34. In operation, an RF source 50, a pulse circuit 51, and a bias matching circuit 52 can be used to bias the substrate support 32 and control the ion energy.
[0061] A gas delivery system 56 can be used to supply the process gas mixture to the processing chamber 28. The gas delivery system 56 can include a process inert gas source 57, a gas metering system 58, such as valves and mass flow controllers, and a manifold 59. A gas injector 63 can be positioned at the center of the dielectric window 24 and is used to inject the gas mixture from the gas delivery system 56 into the processing chamber 28. Additionally or alternatively, the gas mixture can be injected from a side of the processing chamber 28.
[0062] A heater / chiller 64 can be used to heat / cool the substrate support 32 to a predetermined temperature. An exhaust system 65 includes valves 66 and pumps 67 for controlling the pressure within the process chamber and / or for removing reactants from the process chamber 28 by purging or vacuum degassing.
[0063] The etching process can be controlled using a controller 54. The controller 54 monitors system parameters and controls the delivery of gas mixtures, striking the plasma, maintaining and extinguishing the plasma, removing reactants, providing cooling gases, etc. Additionally, as described below, the controller 54 may control various aspects of the coil driver circuit 10, the RF source 50, the bias matching circuit 52, etc.
[0064] FIG. 1B illustrates an example of a substrate processing system 100 that includes a process chamber 102. Although the example here is described in the context of plasma-enhanced chemical vapor deposition (PECVD), the teachings of the present disclosure are applicable to other types of substrate processing, such as atomic layer deposition (ALD), plasma-enhanced ALD (PEALD), CVD, or other processes including etch processes. The system 100 includes a process chamber 102 that encloses other components of the system 100 and has an RF plasma (if used). The process chamber 102 includes an upper electrode 104 and an electrostatic chuck (ESC) 106 or other substrate support. During operation, a substrate 108 is positioned on the ESC 106.
[0065] For example, the upper electrode 104 can include a gas distribution device 110, such as a showerhead, for introducing and distributing process gases. The gas distribution device 110 can include a stem with one end connected to the top surface of the processing chamber 102. The base portion of the showerhead is generally cylindrical and extends radially outward from the opposite end of the stem at a location spaced from the top surface of the processing chamber 102. The surface of the showerhead base portion that faces the substrate, or faceplate, includes a number of holes through which vaporized precursors, process gases, or purge gases pass. Alternatively, the upper electrode 104 can include a conductive plate, and the process gases can be introduced in another manner.
[0066] The ESC 106 includes a base plate 112 that acts as a bottom electrode. The base plate 112 supports a heating plate 114, which may correspond to a ceramic multi-zone heating plate. A thermally resistive layer 116 may be disposed between the heating plate 114 and the base plate 112. The base plate 112 may include one or more channels 118 for flowing a coolant through the base plate 112.
[0067] If a plasma is used, the RF generating system 120 generates and outputs an RF voltage to one of the upper electrode 104 and the lower electrode (e.g., the base plate 112 of the ESC 106). The other of the upper electrode 104 and the base plate 112 may be DC grounded, AC grounded, or ungrounded (floating). By way of example only, the RF generating system 120 may include an RF generator 122 that generates RF power that is delivered to the upper electrode 104 or the base plate 112 by a match and distribution network 124. In other examples, the plasma may be generated inductively or remotely.
[0068] Gas delivery system 130 includes one or more gas sources 132-1, 132-2, ... 132-N (collectively referred to as gas sources 132), where N is an integer greater than 0. Gas sources 132 are connected to manifold 140 by valves 134-1, 134-2, ... 134-N (collectively referred to as valves 134), as well as mass flow controllers 136-1, 136-2, ... 136-N (collectively referred to as mass flow controllers 136). Vapor delivery system 142 provides vaporized precursor to manifold 140 or to a separate manifold (not shown) connected to process chamber 102. The output of manifold 140 is provided to process chamber 102.
[0069] The temperature controller 150 can be connected to a number of thermal control elements (TCEs) 152 disposed within the heating plate 114. The temperature controller 150 can be used to control the number of TCEs 152 to control the temperature of the ESCs 106 and the substrate 108. The temperature controller 150 can be in communication with a coolant assembly 154 to control the flow of coolant through the channels 118. For example, the coolant assembly 154 can include a coolant pump, a reservoir, and one or more temperature sensors (not shown). The temperature controller 150 operates the coolant assembly 154 to selectively flow coolant through the channels 118 to cool the ESCs 106. The valves 156 and pumps 158 can be used to evacuate reactants from the processing chamber 102. A system controller 160 controls the components of the system 100.
[0070] Figures 2-4 show simplified schematic diagrams of an ESC and microchannels. Figure 2 shows a simplified schematic cross-sectional view of the substrate support 32 shown in Figure 1A and an ESC without microchannels, such as ESC 106 shown in Figure 1B. All references below to ESC 106 should be understood to also refer to substrate support 32. Figure 3 shows a simplified cross-sectional view of an ESC with microchannels according to the present disclosure. Figure 4 shows a schematic diagram of an ESC with microchannels.
[0071] In Figures 2 and 3, the vertical line on the left hand side indicates a line through the center of the ESC. Thus, the cross sections in Figures 2 and 3 show only the right hand side of the ESC cross section. The left hand side of the ESC cross section is a mirror image of the right hand side of the ESC cross section. Additionally, many structures of the ESC have been omitted for ease of illustration and to highlight where the microchannels are located within the ESC.
[0072] In FIG. 2, the ESC 200 (similar to elements 32 and 106 shown in FIGS. 1A and 1B, respectively) comprises a base plate 202 (e.g., base plate 112 shown in FIG. 1B), a ceramic layer (also referred to as a dielectric layer) 204 disposed on the base plate 202, and an RF electrode 206 disposed within the ceramic layer 204. During processing, a wafer 208 may be disposed on the ceramic layer 204. RF power is provided to the RF electrode 206, for example, while performing an etching process on the wafer 208 or while depositing a dielectric layer on the wafer 208. The base plate 202 is the metal body of the ESC 200 and contains other structures of the ESC 106, such as the cooling channels 118 shown in FIG. 1B, the heating plate 114 (which typically includes a resistive trace located between the metal body and the ceramic layer or embedded in the ceramic layer), and the thermal resistance layer 116. In other words, elements 202 include elements 114 , 116 , and 118 of ESC 106 .
[0073] Throughout this disclosure, the portion of the ceramic layer 204 above the RF electrode 206 and below the wafer 208 (i.e., between the RF electrode 206 and the wafer 208) is referred to as the upper ceramic layer (or upper dielectric layer) 204-1. The portion of the ceramic layer 204 below the RF electrode 206 and above the base plate 202 (i.e., between the RF electrode 206 and the base plate 202) is referred to as the lower ceramic layer (or lower dielectric layer) 204-2.
[0074] 3 shows an ESC 250 that includes a region 252 of variable effective dielectric constant in the top ceramic layer 204-1. The variable dielectric constant is provided by inserting a microfluidic channel (referred to as a microchannel throughout this disclosure) or a porous medium into the region 252 in the top ceramic layer 204-1. The dielectric constant is changed by filling the microchannel with air or a fluid, as described in more detail below. The region 252 that includes the microchannel is also referred to as a microchannel region 252, or simply a microchannel 252, throughout this disclosure. The microchannel 252 is located in the top ceramic layer 204-1 directly below the wafer 208 and directly above the RF electrode 206.
[0075] Figure 4 shows a schematic diagram of the ESC 250 from Figure 3, including a microchannel region 252. Also shown in Figure 4 is a partial view of a channel 254 for filling and emptying the microchannel. Also shown in Figure 4 is an RF transfer structure 256, and a minimum contact feature 258.
[0076] The microchannel 252 shown in FIG. 4 is an example. For example, FIG. 4 illustrates a case where the layout of the microchannel 252 is annular. However, the present disclosure is not so limited. In some applications, multiple such annular microchannels 252-1, 252-2 may be disposed within the ceramic layer 204, as shown in FIG. 5. Furthermore, multiple such annular microchannels 252-1, 252-2 may have different widths W1, W2 as shown, or may be the same width (i.e., W1 and W2 may be equal).
[0077] Alternatively, the microchannels 252 may be sector-shaped, as shown in Figure 6. Although only one sector is shown in Figure 6, the microchannels may be arranged in multiple sectors, depending on the application. Furthermore, the arc lengths (i.e., area size) of the sectors may be the same or different. Furthermore, the sectors may extend from the center all the way to the edge of the circumference, or from the center partway to the edge of the circumference.
[0078] The microchannels 252 can be arranged in the ceramic layer 204 as many other geometric shapes, such as circles, ellipses, squares, rectangles, hexagons, and the like. Additionally, any combination of these arrangements and shapes is within the scope of the present disclosure. Additionally, in some applications, the microchannels 252 may be arranged in the ceramic layer 204 to cover the entire area under the wafer 208. These shapes and arrangements may include any of the configurations of microchannels 252 shown and described with reference to FIGS. 11-15 and may be arranged in the ESC in any of the ways shown and described with reference to FIGS. 16-19.
[0079] In some applications, different fluids may be filled into two separate microchannels (e.g., in two different annular regions 252-1, 252-2 shown in FIG. 5) to achieve two different etch rates. In some applications where the microchannels 252 are arranged in a number of different shapes, one set of shapes may be filled with one fluid and another set of shapes with another fluid to vary the etch rate across different regions of the wafer, depending on the application. Various apparatus and methods for filling and emptying the microchannels 252 may be used, as described below with reference to FIGS. 7-10.
[0080] During processing of a wafer, if a higher etch (or deposition) rate is desired in a region of the wafer, the microchannel 252 beneath that region is filled with the appropriate fluid and then the associated process step is performed. Subsequently, if a lower etch rate is desired in a region of the wafer, the fluid beneath that region is removed from the microchannel 252 and the next process step is performed.
[0081] Alternatively, two different fluids can be alternately filled into the same microchannel 252 to achieve two different etch rates within an area of the wafer. For example, before performing a first process step, the microchannel 252 can be filled with a first fluid, and the first process step can be performed at the first etch rate. If a different second etch rate (faster or slower than the first etch rate) is then desired, the first fluid is removed from the microchannel 252, the microchannel 252 is filled with a second fluid (instead of air), and the second process step is performed at the second etch rate. As another alternative, instead of using a fluid and air, two different fluids can be used to improve thermal conductivity while also changing the dielectric constant of the material under the wafer area. Also, various apparatuses and methods for filling and emptying microchannels described below with reference to Figures 7-10 can be used.
[0082] Furthermore, as described in more detail below, in some examples, it may be desirable to achieve two different etch rates in two different sections of the wafer. To do this, two separate sets of microchannels 252 (e.g., using any of the shapes and configurations described above with reference to Figures 5 and 6) may be placed under two different sections of the wafer. Two different fluids may be filled into the two separate microchannels 252 to achieve two different etch rates. The two different etch rates in the two different sections of the wafer may be achieved during the same process step or during two different process steps. The filling and emptying of the two sets of microchannels may be adjusted accordingly. Again, various apparatuses and methods for filling and emptying the microchannels 252 may be used, as described below with reference to Figures 7-10.
[0083] 7-10, only one fluid is shown as the fluid used to fill the microchannel 252, but it is understood that two different fluids may be used to fill two separate microchannels 252 using similar apparatus as well. Additionally, as previously discussed, the fluid used to fill the microchannel 252 may include a liquid metal. Examples of liquid metals include mercury and low melting point bismuth / antimony / gallium / indium containing alloys (e.g., the melting point of a gallium-indium eutectic alloy with 74.5 wt % Ga is 15.7 degrees Celsius).
[0084] The microchannels 252 can generally be positioned about 1-2 millimeters below the wafer 208. That is, there may be about 1-2 millimeters of ceramic material (of the top ceramic layer 204-1) between the microchannels 252 and the wafer 208. Furthermore, when designing the microchannels 252 for a particular application, the pitch of the microchannels 252 can be decreased as the distance between the microchannels 252 and the wafer 208 decreases, as shown in various layouts and configurations of the microchannels 252 described in detail below with reference to Figures 13-19.
[0085] That is, the closer the micro-channels 252 are disposed to the wafer 208, the narrower the micro-channels 252 can be and the closer they are spaced from one another within the upper ceramic layer 204-1. Conversely, the farther the micro-channels 252 are disposed from the wafer 208, the wider the micro-channels 252 can be and the farther they are spaced from one another within the upper ceramic layer 204-1. Furthermore, depending on the particular application, the width of the micro-channels 252 may vary toward the periphery of the ceramic layer 204 rather than toward the center of the ceramic layer 204. In general, the width of the micro-channels 252 can be greater than the height of the micro-channels 252.
[0086] Detailed examples of the microchannels 252, including example layouts and dimensions of the microchannels 252, are shown and described below with reference to Figures 11-15. Prior to that, various examples of apparatus and methods for filling and emptying the microchannels 252 are described with reference to Figures 7-10. Figures 7-10 show highly simplified schematic diagrams of the ESC 250. These figures omit many of the structural details associated with the ESC 250 in order to emphasize the apparatus and methods for filling and emptying the microchannels 252.
[0087] 7 shows a first example, an apparatus 700, for filling and emptying the microchannel 252. In the first example, coolant from the coolant assembly 154 shown in FIG. 1B, which would normally supply the cooling channel 118 in the base plate 202 of the ESC 250, is also supplied to the microchannel 252. Valves V1 and V2 are used to fill and empty the microchannel 252. Valves V1 and V2 are controlled by the controller 54 shown in FIG. 1A or the system controller 160 shown in FIG. 1B as follows. In the following, all references to the system controller 160 should be understood to also refer to the controller 54.
[0088] To fill the microchannel 252 with coolant, valve V2 is closed and valve V1 is opened. Valve V1 allows some of the coolant that has entered the cooling channel 118 to also enter the microchannel 252. After the microchannel 252 is filled, the desired processing step is performed on the wafer 208 with its filled microchannel 252. To then empty the microchannel 252, valve V1 is closed and valve V2 is opened. Air flows through valve V2, displacing the coolant from the microchannel 252.
[0089] 8 shows a second example apparatus 800 for filling and emptying the microchannel 252. In the second example, the microchannel 252 is supplied with an alternative medium instead of the coolant supplied to the cooling channel 118. The medium is supplied from a source (not shown) that is separate from the coolant assembly 154 and external to the ESC 250. Valves V1 and V2 are used to fill and empty the microchannel 252. Valves V1 and V2 are controlled by the system controller 160 (shown in FIG. 1) as follows:
[0090] To fill the microchannel 252 with medium, valve V2 is closed and valve V1 is opened. Valve V1 allows medium from a source to flow into the microchannel 252. After the microchannel 252 is filled, the wafer 208 with the filled microchannel 252 is subjected to the desired processing step. Then, to empty the microchannel 252, valve V1 is closed and valve V2 is opened. Air flows through valve V2, displacing the coolant from the microchannel 252. Valve V3 is optional and is used to control the exhaust of the medium (e.g., for waste collection) through an exhaust line connected to valve V3.
[0091] FIG. 9 shows a third example, apparatus 900, for filling and emptying the microchannel 252. In the third example, the microchannel 252 is supplied with an alternative medium instead of the coolant supplied to the cooling channel 118. The medium is supplied from a source that is separate from the coolant assembly 154 and external to the ESC 250. Specifically, the apparatus 900 uses a closed system including two reservoirs R1 and R2 and valves V11-V17. The apparatus 900 uses air pressure to transport the medium from the reservoir R2 to the microchannel 252, to the reservoir R1, and back to the reservoir R2. That is, the apparatus 900 uses air pressure to fill and empty the microchannel 252. The valves V11-V17 are controlled by the system controller 160 (shown in FIG. 1) as shown in truth table 902.
[0092] Specifically, as shown in truth table 902, valves V12, V15, and V17 are closed (indicated by X in truth table 702) and valves V11, V13, V14, and V16 are opened (indicated by O in truth table 702) to fill micro-channel 252 with media from reservoir R2. A level sensor 704 associated with reservoir R1 indicates completion of the fill operation to system controller 160 upon completion of the fill operation. Valves V11-V17 are then closed during wafer processing while keeping micro-channel 252 filled with media. After micro-channel 252 is filled, the wafer 208 with the filled micro-channel 252 is subjected to the desired processing steps.
[0093] Subsequently, valves V12, V15, and V17 are closed and valves V11, V13, V14, and V16 are opened to drain the microchannel 252 into the reservoir R1. After the valves V11, V13, V14, and V16 are opened, all the medium remaining in the reservoir R2 is blown from the reservoir R2 into the reservoir R1. This step ends when the reservoir R2 is empty, which can be detected, for example, by a drop in air pressure at the valve V16 or by a level sensor. To transfer the medium from the reservoir R1 to the reservoir R2, valves V11, V13, V14, and V16 are closed and valves V12, V15, and V17 are opened. The level sensor 904 associated with the reservoir R1 indicates the completion of the transfer to the system controller 160 when the transfer is complete.
[0094] Overall, medium flows from reservoir R2 into microchannel 252. Any medium remaining in reservoir R2 is then blown into reservoir R1. The medium in reservoir R1 is then pushed out into reservoir R2 (this operation can be performed in parallel with another process step, for example, to save processing time). At this point, apparatus 900 is reset and ready to fill microchannel 252 with medium from reservoir R2.
[0095] 10 illustrates a fourth example apparatus 1000 for filling and emptying the microchannels 252. In the fourth example, the microchannels 252 are supplied with an alternative medium instead of the coolant supplied to the cooling channels 118. The medium is supplied by a source that is separate from the coolant assembly 154 and external to the ESC 250. Specifically, the apparatus 1000 uses a valveless closed system that includes two reservoirs 1002, 1004 and a heater 1006 associated with the reservoir 1002. The apparatus 1000 transports the medium by thermal expansion. The system controller 160 (shown in FIG. 1) controls the amount of power supplied to the heater 1006.
[0096] Specifically, when the reservoir 1002 becomes cold (e.g., by the heater 1006 being turned off or low powered), the medium contracts and is drawn into the reservoir 1002. When the medium level in the reservoir 1004 falls below the dip tube 1010, air flows through the air filter 1008 into the reservoir 1004 and fills the microchannel 252. When the heater 1006 heats the reservoir 1002 (e.g., by the heater 1006 being turned on or high powered) due to thermal expansion of the medium in the reservoir 1002, medium from the reservoir 1002 fills the microchannel 252. Excess fluid is exhausted into the reservoir 1004 (also referred to as the overflow reservoir). Air is exhausted from the microchannel 252 into the reservoir 1004 and from the reservoir 1004 through the filter 1010 to the outside.
[0097] After the microchannels 252 are filled, the wafer 208 with the filled microchannels 252 is subjected to the desired processing steps. The reservoir 1002 is then cooled (e.g., by turning off or applying low power to the heater 1006) to remove the medium from the microchannels 252. When the reservoir 1002 cools (e.g., by turning off or applying low power to the heater 1006), the medium contracts and is drawn from the microchannels 252 into the reservoir 1002. When the medium level in the reservoir 1004 falls below the dip tube 1010, air flows through the air filter 1008 into the reservoir 1004, filling the microchannels 252 and discharging the medium in the microchannels 252 instead.
[0098] 11-15 show various layouts and configurations of the microchannel 252. For example, FIG. 11 shows that the microchannel 252 can be serpentine in shape (actual examples are shown in FIGS. 13-15). The serpentine channel can be continuous in shape and can extend along the periphery of the ceramic layer 204, as shown at 252 in FIG. 4. In another example, FIG. 12 shows that the microchannel 252 can be in the form of a wide channel with porous filling. The wide channel can be continuous in shape and can extend along the periphery of the ceramic layer 204, as shown at 252 in FIG. 4.
[0099] FIG. 13 shows another example of a microchannel 252. In this example, the serpentine segments may be in the form of a continuous channel connected in series. The continuous channel is circular and extends around the circumference of the ceramic layer 204, as shown at 252 in FIG. 4. The number of twists in the serpentine segments may vary. The direction of fluid flow through the microchannel 252 is indicated by the arrows in the figure.
[0100] FIG. 14 shows another example of a microchannel 252. In this example, the microchannel 252 may be in the form of a continuous channel with serpentine segments connected in parallel within a manifold 1402 of the ceramic layer 204. The continuous channel is annular and extends around the circumference of the ceramic layer 204, as shown at 252 in FIG. 4. Again, the number of twists in the serpentine segments may vary. The direction of fluid flow through the microchannel 252 is indicated by the arrows. Although not shown, the channel width may be varied to equalize the pressure drop between the serpentine segments.
[0101] FIG. 15 shows yet another example of a microchannel 252. In this example, the microchannel 252 is radially arranged in the ceramic layer 204. As shown in FIG. 4 at 252, the microchannel 252 is formed by arranging a plurality of radial grooves 1502 between a pair of annular concentric grooves 1504-1, 1504-2 (collectively referred to as annular concentric grooves 1504) arranged in the ceramic layer 204. The radial grooves 1502 have smaller dimensions than the annular concentric grooves 1504. The outer annular concentric groove 1504-1 is supplied with a fluid. The fluid flows radially inward from the periphery to the center through the plurality of radial grooves 1502. The fluid enters the outer annular concentric groove 1504-2.
[0102] Alternatively, the direction of fluid flow through the radial grooves 1502 can be reversed (i.e., fluid can flow radially outward, away from the center, through the radial grooves 1502). Fluid is provided to the inner annular concentric groove 1504-2. Fluid flows radially outward, from the center to the periphery, through the radial grooves 1502. Fluid enters the outer annular concentric groove 1504-2.
[0103] 16-19 show various example configurations of an ESC with a micro-channel 252. FIG. 16 shows a first configuration, ESC 1600, in which the RF electrode 206 is also the clamping electrode. That is, the RF electrode 206 is powered with DC (direct current power) along with RF (radio frequency power) to clamp the wafer 208. The micro-channel 252 has a pitch p and a height h, and the walls of the micro-channel 252 have a width w. By way of example only, the pitch p may be about 400 um, the height h may be about 300 um, and the width w may be about 100 um. Other dimensions are possible.
[0104] The microchannel 252 is located directly above the metallic RF electrode 206. This structure (i.e., the microchannel 252 located directly above the RF electrode 206) is covered by a dielectric sheet (element 204-1 shown in Figures 3 and 4). By way of example only, the height or thickness t of the dielectric sheet may be about 200 μm. Other dimensions are possible.
[0105] Thus, the top ceramic layer 204-1 is disposed directly above the structure formed by the microchannel 252, which is disposed directly above the RF electrode 206. In other words, the microchannel 252 is disposed directly above the RF electrode 206 and directly below the top ceramic layer 204-1 (or between the RF electrode 206 and the top ceramic layer 204-1).
[0106] 17 shows a second configuration of the ESC 1700, where the RF electrode 206 is separated from the clamping electrode 1702, where the RF electrode 206 is powered with RF (radio frequency power) and the clamping electrode 1702 is powered with DC (direct current power). In the illustrated example, both electrodes have the same height or thickness (e.g., 25 μm). However, the two electrodes 206, 1702 may have different dimensions. Furthermore, the dimensions of the two electrodes, either the same or different, may be dimensions other than 25 μm.
[0107] The microchannel 252 is disposed between the two electrodes 206, 1702. The microchannel 252 has a pitch p and a height h, and the walls of the microchannel 252 have a width w. By way of example only, the pitch p may be about 500 um, the height h may be about 300 um, and the width w may be about 100 um. Other dimensions may also be used. This structure (i.e., the microchannel 252 disposed directly above the RF electrode 206 and directly below the clamping electrode 1702) is covered by a dielectric sheet (element 204-1 shown in Figures 3 and 4). By way of example only, the height or thickness t of the dielectric sheet may be about 100 μm. Other dimensions may also be used.
[0108] The top ceramic layer 204-1 is disposed directly above the structure formed by the microchannel 252, which is disposed between the RF electrode 206 and the clamping electrode 1702. That is, the clamping electrode 1702 is disposed directly below the top ceramic layer 204-1, the microchannel 252 is disposed directly below the clamping electrode 1702, and the RF electrode 206 is disposed directly below the microchannel 252.
[0109] RF power from the RF electrode 206 effectively passes through the dielectric sheet (element 204-1). However, because the clamp electrode 1702 is at an equipotential and would therefore negate the spatial modulation of RF current caused by the underlying microchannel 252, the microchannel 252 needs to be covered by a portion of the clamp electrode 1702 that is isolated from an RF perspective from the portion of the clamp electrode 1702 that is above the non-channel portion of the ESC surface. Figure 18 shows an example of such a configuration, with a segmented clamp electrode.
[0110] 18 shows a third configuration, ESC 1800, in which the RF electrode 206 is separated from the clamp electrode 1802, and the clamp electrode 1802 is segmented. The third configuration is the same as the second configuration, except that the clamp electrode 1802 is segmented as follows: For example, only two segments of the clamp electrode 1802 are shown, 1802-1 and 1802-2. Segments 1802-1 and 1802-2 together constitute the outer clamp electrode 1802.
[0111] Microchannel 252 is covered by a portion 1802-1 of clamp electrode 1802 that is isolated from an RF perspective from portion 1802-2 of clamp electrode 1802 that is above the non-channel portion of ESC 1800. Portion 1802-1 of clamp electrode 1802 is positioned directly above microchannel 252, while portion 1802-2 of clamp electrode 1802 is separated by a dielectric (element 204-2 shown in Figures 3 and 4) and does not have microchannel 252 underneath it.
[0112] FIG. 19 shows a fourth configuration, ESC 1900. In this configuration, the RF electrode 206 is separated from the clamp electrode 1902, and the clamp electrode 1902 is segmented. The fourth configuration is the same as the third configuration, except that a dielectric (part of element 204-1) is inserted above the microchannel 252 and below the clamp electrode 1902 (i.e., between the microchannel 252 and the clamp electrode 1902). For example, only two segments of the clamp electrode 1902, 1902-1 and 1902-2, are shown. Segments 1902-1 and 1902-2 together constitute the outer clamp electrode 1902. This configuration has the advantage that the dielectric above the microchannel 252 (i.e., part of element 204-1) allows the microchannel 252 to be filled with a liquid metal or other conductive liquid.
[0113] The schematic diagram of Figure 20 shows how the segmented clamping electrodes (elements 1802, 1902) can be powered from a clamping (DC) power supply. The system 1800 includes a DC power supply 2002 that provides DC power to the segmented clamping electrodes (e.g., elements 1802 or 1902) of an ESC (e.g., ESC 1800 or 1900) having a microchannel 252. The clamping electrodes include an outer clamping electrode 2004 and an inner clamping electrode 2006.
[0114] The outer clamping electrode 2004 is separated into segment 2004-1, which overlies the microchannel 252, and segment 2004-2, which does not overlie the microchannel 252. Segment 2004-1 is similar to segments 1802-1, 1902-1 shown in Figures 18 and 19. Segment 2004-2 is similar to segments 1802-2, 1902-2 shown in Figures 18 and 19. Segments 2004-1 and 2004-2 together comprise the outer clamping electrode 2004.
[0115] The inner clamping electrode 2006 is not segmented and has no microchannels 252 near, adjacent to, or beneath it. The two outer segments 2004-1 and 2004-2 of the outer clamping electrode 2004 are fed through separate (respective) filter resistors that separate the inner zone of the clamping electrode from the outer zone in terms of RF, while allowing microamp level DC current for clamping.
[0116] In various embodiments described herein, when a separate clamping electrode is used, there are no intervening components, such as heating elements, between the top surface of the ceramic layer (the surface on which the wafer sits directly) and the clamping electrode, between the clamping electrode and the microchannel, between the microchannel and the RF electrode, and between the RF electrode and the bottom surface of the ceramic layer (the surface that sits directly on the base plate). Also, when a separate clamping electrode is not used, there are no intervening components, such as heating elements, between the top surface of the ceramic layer and the microchannel, between the microchannel and the RF electrode, and between the RF electrode and the bottom surface of the ceramic layer. Thus, in use, the ceramic layer includes only the clamping electrode, the microchannel, and the RF electrode. The wafer is placed directly on the top surface of the ceramic layer, and the bottom surface of the ceramic layer is placed directly on the metal base plate.
[0117] Throughout this disclosure, fluids can include liquids and / or gases. Also, when a fluid is exhausted from a microchannel, air replaces the exhausted fluid unless another fluid is used to replace the exhausted fluid. In some embodiments, a vacuum can replace the exhausted fluid. In general, any fluid that has a higher dielectric constant than air and a better thermal conductivity than air can be used to fill the microchannel.
[0118] Furthermore, throughout this disclosure, the term filling and draining a microchannel means fully filling and fully draining the microchannel, partially filling and fully draining the microchannel, fully filling and partially draining the microchannel, or partially filling and partially draining the microchannel. Typically, the microchannel can be filled such that the level of the fluid increases to a first level and drained such that the level of the fluid decreases to a second level lower than the first level. The first level can mean fully or partially filling the microchannel. The second level can mean fully or partially draining the fluid from the microchannel. In other words, the level or amount of fluid in the microchannel can be varied or altered by using different devices and by using different configurations and layouts of the microchannels described above to change the dielectric constant of the material between the RF electrode and the wafer.
[0119] The foregoing description is merely exemplary in nature and is not intended to limit the disclosure, its application, or uses. The broad teachings of the disclosure can be embodied in various forms. Thus, while the disclosure includes specific examples, the true scope of the disclosure should not be limited to such examples, since other modifications will become apparent upon review of the drawings, the specification, and the following claims. It should be understood that one or more steps in a method may be performed in different orders (or simultaneously) without altering the principles of the disclosure. Furthermore, although each embodiment is described above as having certain features, any one or more of these features described with respect to any embodiment of the disclosure can be implemented in other embodiments and / or combined with any features of the other embodiments (even if such combination is not explicitly described). In other words, the described embodiments are not mutually exclusive, and it is within the scope of the disclosure to substitute one or more embodiments for one another.
[0120] Spatial and functional relationships between elements (e.g., between modules, between circuit elements, between semiconductor layers, etc.) are described using various terms such as "connected," "engaged," "coupled," "adjacent," "next to," "on," "above," "below," and "disposed." Also, in the above disclosure, when a relationship between a first element and a second element is described, unless expressly described as "direct," the relationship may be a direct relationship in which there are no other intervening elements between the first element and the second element. However, there may also be an indirect relationship in which one or more intervening elements (spatial or functional) exist between the first element and the second element. As used herein, the phrase at least one of A, B, and C should be interpreted in the sense of a logic (A or B or C) using a non-exclusive logical OR, and not in the sense of "at least one of A, at least one of B, and at least one of C."
[0121] In some implementations, the controller is part of a system, such as may be part of the examples described above. Such systems may include semiconductor processing equipment including one or more processing tools, one or more chambers, one or more processing platforms, and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems may be integrated with electronics for controlling the operation of the system before, during, and after processing of a semiconductor wafer or substrate. This electronics may be referred to as a "controller" and may control various components or subcomponents of one or more systems.
[0122] The controller may be programmed to control any of the processes disclosed herein depending on the processing requirements and / or type of system, including delivery of process 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, position and motion settings, wafer loading and unloading to and from the tool, and other transport tools and / or load locks connected or interfaced with the particular system.
[0123] Broadly, a controller may be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receives instructions, issues instructions, controls operations, enables cleaning operations, enables endpoint measurements, etc. 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, i.e., microcontrollers, that execute program instructions (e.g., software).
[0124] Program instructions may be instructions communicated to the controller in the form of various individual settings (or program files) that define operational parameters for performing a particular process on or for a semiconductor wafer or for a system. The operational parameters may, in some embodiments, be part of a recipe defined by a process engineer for implementing one or more processing steps in the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or wafer dies.
[0125] The controller, in some embodiments, may be part of a computer that is integrated or coupled with the system or otherwise networked to the system, or may be coupled to such a computer, or a combination thereof. For example, the controller may be in the "cloud" or all or part of a fab host computer system. This allows for remote access of wafer processing. The computer may allow remote access to the system to monitor the current progress of a fabrication operation, review the history of past fabrication operations, review trends or performance criteria from multiple fabrication operations, change parameters of a current process, set up processing steps following the current process, or initiate a new process.
[0126] In some examples, a remote computer (e.g., a server) can provide a process recipe to the system over a network. Such a network may include a local network or the Internet. The remote computer may include a user interface that allows entry or programming of parameters and / or settings, which are then communicated from the remote computer to the system. In some examples, the controller receives instructions in the form of data. Such data identifies parameters for each of the processing steps to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process being performed and the type of tool the controller is configured to interface with or control.
[0127] Thus, as discussed above, the controller may be distributed, for example, by having one or more individual controllers networked together and cooperating toward a common purpose, such as the processes and controls described herein. An example of a distributed controller for such purposes would include one or more integrated circuits on the chamber that are located remotely (e.g., at the platform level or as part of a remote computer) and communicate with one or more integrated circuits that are coupled to control the process on the chamber.
[0128] Exemplary systems may include, but are not limited to, a plasma etch chamber or module, a deposition chamber or module, a spin rinse chamber or module, a metal plating chamber or module, a cleaning chamber or module, a bevel edge etch chamber or module, a physical vapor deposition (PVD) chamber or module, a chemical vapor deposition (CVD) chamber or module, an atomic layer deposition (ALD) chamber or module, an atomic layer etch (ALE) chamber or module, an ion implantation chamber or module, a tracking chamber or module, and any other semiconductor processing system that may be associated with or used in the fabrication and / or manufacturing of semiconductor wafers.
[0129] As described above, depending on the process step or steps being performed by the tool, the controller may communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, nearby tools, tools located throughout the factory, a main computer, another controller, or tools used for material transport to and from tool locations and / or load ports within a semiconductor manufacturing factory. Furthermore, the present disclosure can be realized in the following forms. [Form 1] 1. A substrate support assembly for supporting a semiconductor substrate in a processing chamber, comprising: a base plate disposed within the processing chamber; a dielectric layer disposed on the base plate and supporting the semiconductor substrate; an electrode disposed within the dielectric layer along a horizontal surface; a plurality of channels disposed in the dielectric layer along the horizontal plane on a surface of the electrode opposite the base plate for transporting a fluid; A substrate support assembly comprising: [Form 2] 2. A system including a substrate support assembly according to claim 1, comprising: a power supply for providing power to the electrode during processing of the semiconductor substrate in the processing chamber; a fluid source for supplying and filling the plurality of channels with the fluid prior to processing of the semiconductor substrate; Including, the system. [Form 3] 2. A system including a substrate support assembly according to claim 1, comprising: a plurality of cooling channels disposed within the base plate; a power supply for providing power to the electrode during processing of the semiconductor substrate in the processing chamber; a coolant source for supplying coolant to the cooling channels during the processing of the semiconductor substrate; a plurality of valves in fluid communication with the coolant source, the cooling channel, and the plurality of channels; supplying the coolant from the coolant source to the cooling channel; providing the coolant as the fluid to fill the plurality of channels to a first level prior to performing a first process on the semiconductor substrate; A controller for controlling the plurality of valves; Including, the system. [Form 4] The system according to aspect 3, The controller is further configured to drain the coolant from the plurality of channels to a second level after performing the first process and before performing a second process on the semiconductor substrate. [Form 5] The system according to claim 4, The system, wherein the first level indicates that the plurality of channels are completely filled with the coolant and the second level indicates that the plurality of channels are completely empty. [Form 6] 2. A system including a substrate support assembly according to claim 1, comprising: a power supply for providing power to the electrode during processing of the semiconductor substrate in the processing chamber; a fluid source for supplying the fluid; a plurality of valves in fluid communication with the fluid source and the plurality of channels; a controller that controls the plurality of valves to fill the plurality of channels with the fluid to a first level before performing a first process on the semiconductor substrate; Including, the system. [Form 7] The system according to claim 6, The controller is further configured to drain the fluid from the plurality of channels to a second level after performing the first process and before performing a second process on the semiconductor substrate. [Form 8] 8. The system of claim 7, wherein the first level indicates that the plurality of channels are completely filled with the fluid, and the second level indicates that the plurality of channels are completely empty. [Form 9] 1. A system comprising: A substrate support assembly as claimed in claim 1; a power supply for providing power to the electrode during processing of the semiconductor substrate in the processing chamber; a fluid source for supplying the fluid; a heater associated with the fluid source; a controller that powers the heater and fills the plurality of channels with the fluid to a first level before performing a first process on the semiconductor substrate; Including, the system. [Form 10] 10. The system according to claim 9, The controller is further configured to vary the power supplied to the heater to remove the fluid from the multiple channels to a second level after performing the first process and before performing a second process on the semiconductor substrate. [Form 11] 11. The system of claim 10, The system, wherein the first level indicates that the plurality of channels are completely filled with the fluid and the second level indicates that the plurality of channels are completely empty. [Form 12] 1. A system comprising: A substrate support assembly as claimed in claim 1; a power supply for providing power to the electrode during processing of the semiconductor substrate in the processing chamber; A first fluid source; a second fluid source for a second fluid; a plurality of valves in fluid communication with the first and second fluid sources and the plurality of channels; filling the plurality of channels with the fluid to a first level prior to performing a first process on the semiconductor substrate; draining the fluid from the plurality of channels after performing the first treatment; filling the plurality of channels with the second fluid to a second level prior to performing a second process on the semiconductor substrate; A controller for controlling the plurality of valves; Including, the system. [Form 13] 13. The system according to claim 12, The first level is equal to the second level. [Form 14] 13. The system according to claim 12, the first level indicates that the plurality of channels is completely filled with the fluid and the second level indicates that the plurality of channels is completely filled with the second fluid; or the first level indicates that the plurality of channels is completely filled with the fluid and the second level indicates that the plurality of channels is partially filled with the second fluid; or the first level indicates that the plurality of channels is partially filled with the fluid, and the second level indicates that the plurality of channels is completely filled with the second fluid; or the first level indicating that the plurality of channels is partially filled with the fluid, and the second level indicating that the plurality of channels is partially filled with the second fluid. [Form 15] 1. A system comprising: A substrate support assembly as claimed in claim 1; a second plurality of channels disposed in the dielectric layer along the horizontal plane on the side of the electrode opposite the base plate; a power supply for providing power to the electrode during processing of the semiconductor substrate in the processing chamber; A first fluid source; a second fluid source for a second fluid; a plurality of valves in fluid communication with the first and second fluid sources, the plurality of channels, and the second plurality of channels; filling the plurality of channels with the fluid to a first level prior to performing a process on the semiconductor substrate; filling the second plurality of channels with the second fluid to a second level prior to performing the process on the semiconductor substrate; A controller for controlling the plurality of valves; Including, the system. [Form 16] 16. The system according to claim 15, The first level is equal to the second level. [Form 17] 16. The system according to claim 15, the first level indicates that the plurality of channels is completely filled with the fluid and the second level indicates that the second plurality of channels is completely filled with the second fluid; or the first level indicates that the plurality of channels is completely filled with the fluid and the second level indicates that the second plurality of channels is partially filled with the second fluid; or the first level indicates that the plurality of channels is partially filled with the fluid, and the second level indicates that the second plurality of channels is completely filled with the second fluid; or the first level indicating that the plurality of channels is partially filled with the fluid, and the second level indicating that the second plurality of channels is partially filled with the second fluid. [Form 18] 1. A system comprising: A substrate support assembly as claimed in claim 1; a second plurality of channels disposed in the dielectric layer along the horizontal plane on the side of the electrode opposite the base plate; a power supply for providing power to the electrode during processing of the semiconductor substrate in the processing chamber; A first fluid source; a second fluid source for a second fluid; a plurality of valves in fluid communication with the first and second fluid sources, the plurality of channels, and the second plurality of channels; filling the plurality of channels with the fluid to a first level while the second plurality of channels is empty prior to performing a first process on the semiconductor substrate; draining the fluid from the plurality of channels after performing the first treatment; filling the second plurality of channels with the second fluid to a second level prior to performing a second process on the semiconductor substrate; A controller for controlling the plurality of valves; Including, the system. [Form 19] 19. The system according to claim 18, The first level is equal to the second level. [Form 20] 19. The system according to claim 18, the first level indicates that the plurality of channels is completely filled with the fluid and the second level indicates that the second plurality of channels is completely filled with the second fluid; or the first level indicates that the plurality of channels is completely filled with the fluid and the second level indicates that the second plurality of channels is partially filled with the second fluid; or the first level indicates that the plurality of channels is partially filled with the fluid, and the second level indicates that the second plurality of channels is completely filled with the second fluid; or the first level indicating that the plurality of channels is partially filled with the fluid, and the second level indicating that the second plurality of channels is partially filled with the second fluid. [Form 21] 2. A substrate support assembly as claimed in claim 1, comprising: The plurality of channels are disposed within an annular region of the dielectric layer. [Form 22] 2. A substrate support assembly as claimed in claim 1, comprising: a second plurality of channels disposed in the dielectric layer along the horizontal plane on the side of the electrode opposite the base plate; the plurality of channels are disposed within a first annular region of the dielectric layer; the second plurality of channels are disposed within a second annular region of the dielectric layer; A substrate support assembly, wherein the first and second annular regions have first and second areas, respectively. [Form 23] 2. A substrate support assembly as claimed in claim 1, comprising: The plurality of channels are disposed within a sectoral region of the dielectric layer. [Form 24] 2. A substrate support assembly as claimed in claim 1, comprising: a second plurality of channels disposed in the dielectric layer along the horizontal plane on the side of the electrode opposite the base plate; the plurality of channels are disposed within a first sector of the dielectric layer; the second plurality of channels are disposed within a second sector of the dielectric layer; The first and second sectors have first and second areas, respectively. [Form 25] 2. A substrate support assembly as claimed in claim 1, comprising: The substrate support assembly, wherein the plurality of channels are serpentine shaped. [Form 26] 2. A substrate support assembly as claimed in claim 1, comprising: A substrate support assembly, wherein the plurality of channels are formed of a porous material. [Form 27] 2. A substrate support assembly as claimed in claim 1, comprising: The plurality of channels comprises a plurality of serially connected serpentine portions. [Form 28] 2. A substrate support assembly as claimed in claim 1, comprising: The plurality of channels are disposed in a manifold within the dielectric layer, the manifold having a plurality of serpentine portions connected in parallel within the manifold. [Form 29] 2. A substrate support assembly as claimed in claim 1, comprising: the plurality of channels are formed by disposing two annular grooves in the dielectric layer and disposing a plurality of grooves radially connecting the two annular grooves; A substrate support assembly, wherein each of the plurality of grooves is smaller than the two annular grooves. [Form 30] 2. A system including a substrate support assembly according to claim 1, comprising: a radio frequency power source that supplies radio frequency power to the electrode during processing of the semiconductor substrate in the processing chamber; a DC power supply that supplies DC power to the electrode during the processing of the semiconductor substrate; a fluid source for supplying and filling the plurality of channels with the fluid prior to the processing of the semiconductor substrate; Including, the system. [Form 31] 2. A system including a substrate support assembly according to claim 1, comprising: a second electrode disposed within the dielectric layer on a side of the plurality of channels opposite the electrode along the horizontal plane; a radio frequency power source that supplies radio frequency power to the electrode during processing of the semiconductor substrate in the processing chamber; a DC power supply that supplies DC power to the second electrode during the processing of the semiconductor substrate; a fluid source for supplying and filling the plurality of channels with the fluid prior to the processing of the semiconductor substrate; Including, the system. [Form 32] 32. The system of claim 31, the second electrode includes a first annular segment and a second annular segment; the plurality of channels are disposed within an annular region of the dielectric layer beneath the first annular segment. [Form 33] 32. The system of claim 31, the second electrode includes a first annular segment and a second annular segment; the plurality of channels are disposed within an annular region of the dielectric layer beneath the first annular segment; A portion of the dielectric layer separates the second electrode from the plurality of channels. [Form 34] 32. The system of claim 31, the second electrode includes an outer electrode and an inner electrode; the outer electrode includes a first annular segment and a second annular segment; the plurality of channels are disposed within an annular region of the dielectric layer beneath the first annular segment; a portion of the dielectric layer separating the second electrode from the plurality of channels; The DC power supply is to the first annular segment through a first resistor; to the second annular segment through a second resistor; to the inner electrode via a third resistor; The system supplies the DC power. [Form 35] 2. A substrate support assembly as claimed in claim 1, comprising: The fluid comprises a liquid, a gas, air, a fluorinated liquid, or a liquid metal selected from the group consisting of mercury and an alloy containing bismuth, antimony, gallium and / or indium.
Claims
1. 1. A substrate support assembly for supporting a semiconductor substrate in a processing chamber, comprising: a base plate disposed within the processing chamber; a dielectric layer disposed on the base plate and supporting the semiconductor substrate; an electrode disposed within the dielectric layer along a horizontal surface; a plurality of interconnected channels having an inlet and an outlet separate from the inlet, the channels being disposed on a face of the electrode opposite the base plate along the horizontal plane and enclosed within the dielectric layer, for transporting a fluid; A substrate support assembly comprising:
2. 13. A system including the substrate support assembly of claim 1, comprising: a power supply for providing power to the electrode during processing of the semiconductor substrate in the processing chamber; a fluid source for supplying and filling the plurality of channels with the fluid prior to processing of the semiconductor substrate; Including, the system.
3. 13. A system including the substrate support assembly of claim 1, comprising: a plurality of cooling channels disposed within the base plate; a power supply for providing power to the electrode during processing of the semiconductor substrate in the processing chamber; a coolant source for supplying coolant to the cooling channels during the processing of the semiconductor substrate; a plurality of valves in fluid communication with the coolant source, the cooling channel, and the plurality of channels; supplying the coolant from the coolant source to the cooling channel; providing the coolant as the fluid to fill the plurality of channels to a first level prior to performing a first process on the semiconductor substrate; A controller for controlling the plurality of valves; Including, the system.
4. 4. The system of claim 3, the controller is further configured to drain the coolant from the plurality of channels to a second level after performing the first process and before performing a second process on the semiconductor substrate.
5. 5. The system of claim 4, The system, wherein the first level indicates that the plurality of channels are completely filled with the coolant and the second level indicates that the plurality of channels are completely empty.
6. 13. A system including the substrate support assembly of claim 1, comprising: a power supply for providing power to the electrode during processing of the semiconductor substrate in the processing chamber; a fluid source for supplying the fluid; a plurality of valves in fluid communication with the fluid source and the plurality of channels; a controller that controls the plurality of valves to fill the plurality of channels with the fluid to a first level before performing a first process on the semiconductor substrate; Including, the system.
7. 7. The system of claim 6, The controller is further configured to drain the fluid from the plurality of channels to a second level after performing the first process and before performing a second process on the semiconductor substrate.
8. 8. The system of claim 7, wherein the first level indicates that the plurality of channels are completely filled with the fluid and the second level indicates that the plurality of channels are completely empty.
9. 1. A system comprising: A substrate support assembly according to claim 1; a power supply for providing power to the electrode during processing of the semiconductor substrate in the processing chamber; a fluid source for supplying the fluid; a heater associated with the fluid source; a controller that powers the heater and fills the plurality of channels with the fluid to a first level before performing a first process on the semiconductor substrate; Including, the system.
10. 10. The system of claim 9, The controller is further configured to vary the power supplied to the heater to remove the fluid from the multiple channels to a second level after performing the first process and before performing a second process on the semiconductor substrate.
11. 11. The system of claim 10, The system, wherein the first level indicates that the plurality of channels are completely filled with the fluid and the second level indicates that the plurality of channels are completely empty.
12. 1. A system comprising: A substrate support assembly according to claim 1; a power supply for providing power to the electrode during processing of the semiconductor substrate in the processing chamber; A first fluid source; a second fluid source for a second fluid; a plurality of valves in fluid communication with the first and second fluid sources and the plurality of channels; filling the plurality of channels with the fluid to a first level prior to performing a first process on the semiconductor substrate; draining the fluid from the plurality of channels after performing the first treatment; filling the plurality of channels with the second fluid to a second level prior to performing a second process on the semiconductor substrate; A controller for controlling the plurality of valves; Including, the system.
13. 13. The system of claim 12, The first level is equal to the second level.
14. 13. The system of claim 12, the first level indicates that the plurality of channels is completely filled with the fluid and the second level indicates that the plurality of channels is completely filled with the second fluid; the first level indicates that the plurality of channels is completely filled with the fluid and the second level indicates that the plurality of channels is partially filled with the second fluid; the first level indicates that the plurality of channels is partially filled with the fluid and the second level indicates that the plurality of channels is completely filled with the second fluid; or the first level indicating that the plurality of channels is partially filled with the fluid, and the second level indicating that the plurality of channels is partially filled with the second fluid.
15. 1. A system comprising: A substrate support assembly according to claim 1; a second plurality of channels disposed in the dielectric layer along the horizontal plane on the side of the electrode opposite the base plate; a power supply for providing power to the electrode during processing of the semiconductor substrate in the processing chamber; A first fluid source; a second fluid source for a second fluid; a plurality of valves in fluid communication with the first and second fluid sources, the plurality of channels, and the second plurality of channels; filling the plurality of channels with the fluid to a first level prior to performing a process on the semiconductor substrate; filling the second plurality of channels with the second fluid to a second level prior to performing the process on the semiconductor substrate; A controller for controlling the plurality of valves; Including, the system.
16. 16. The system of claim 15, The first level is equal to the second level.
17. 16. The system of claim 15, the first level indicates that the plurality of channels is completely filled with the fluid and the second level indicates that the second plurality of channels is completely filled with the second fluid; or the first level indicates that the plurality of channels is completely filled with the fluid and the second level indicates that the second plurality of channels is partially filled with the second fluid; the first level indicates that the plurality of channels is partially filled with the fluid and the second level indicates that the second plurality of channels is completely filled with the second fluid; or the first level indicating that the plurality of channels is partially filled with the fluid, and the second level indicating that the second plurality of channels is partially filled with the second fluid.
18. 1. A system comprising: A substrate support assembly according to claim 1; a second plurality of channels disposed in the dielectric layer along the horizontal plane on the side of the electrode opposite the base plate; a power supply for providing power to the electrode during processing of the semiconductor substrate in the processing chamber; A first fluid source; a second fluid source for a second fluid; a plurality of valves in fluid communication with the first and second fluid sources, the plurality of channels, and the second plurality of channels; filling the plurality of channels with the fluid to a first level while the second plurality of channels is empty prior to performing a first process on the semiconductor substrate; draining the fluid from the plurality of channels after performing the first treatment; filling the second plurality of channels with the second fluid to a second level prior to performing a second process on the semiconductor substrate; A controller for controlling the plurality of valves; Including, the system.
19. 20. The system of claim 18, The first level is equal to the second level.
20. 20. The system of claim 18, the first level indicates that the plurality of channels is completely filled with the fluid and the second level indicates that the second plurality of channels is completely filled with the second fluid; or the first level indicates that the plurality of channels is completely filled with the fluid and the second level indicates that the second plurality of channels is partially filled with the second fluid; the first level indicates that the plurality of channels is partially filled with the fluid and the second level indicates that the second plurality of channels is completely filled with the second fluid; or the first level indicating that the plurality of channels is partially filled with the fluid, and the second level indicating that the second plurality of channels is partially filled with the second fluid.
21. 2. The substrate support assembly of claim 1, The plurality of channels are disposed within an annular region of the dielectric layer.
22. 2. The substrate support assembly of claim 1, a second plurality of channels disposed in the dielectric layer along the horizontal plane on the side of the electrode opposite the base plate; the plurality of channels are disposed within a first annular region of the dielectric layer; the second plurality of channels are disposed within a second annular region of the dielectric layer; The first and second annular regions have first and second areas, respectively.
23. 2. The substrate support assembly of claim 1, The plurality of channels are disposed within a sectoral region of the dielectric layer.
24. 2. The substrate support assembly of claim 1, a second plurality of channels disposed in the dielectric layer along the horizontal plane on the side of the electrode opposite the base plate; the plurality of channels are disposed within a first sector of the dielectric layer; the second plurality of channels are disposed within a second sector of the dielectric layer; The first and second sectors have first and second areas, respectively.
25. 2. The substrate support assembly of claim 1, The substrate support assembly, wherein the plurality of channels are serpentine shaped.
26. 2. The substrate support assembly of claim 1, A substrate support assembly, wherein the plurality of channels are formed of a porous material.
27. 2. The substrate support assembly of claim 1, The plurality of channels comprises a plurality of serially connected serpentine portions.
28. 2. The substrate support assembly of claim 1, The plurality of channels are disposed in a manifold within the dielectric layer, the manifold having a plurality of serpentine portions connected in parallel within the manifold.
29. 2. The substrate support assembly of claim 1, the plurality of channels are formed by disposing two annular grooves in the dielectric layer and disposing a plurality of grooves radially connecting the two annular grooves; A substrate support assembly, wherein each of the plurality of grooves is smaller than the two annular grooves.
30. 13. A system including the substrate support assembly of claim 1, comprising: a radio frequency power source that supplies radio frequency power to the electrode during processing of the semiconductor substrate in the processing chamber; a DC power supply that supplies DC power to the electrode during the processing of the semiconductor substrate; a fluid source for supplying and filling the plurality of channels with the fluid prior to the processing of the semiconductor substrate; Including, the system.
31. 13. A system including the substrate support assembly of claim 1, comprising: a second electrode disposed within the dielectric layer on a side of the plurality of channels opposite the electrode along the horizontal plane; a radio frequency power source that supplies radio frequency power to the electrode during processing of the semiconductor substrate in the processing chamber; a DC power supply that supplies DC power to the second electrode during the processing of the semiconductor substrate; a fluid source for supplying and filling the plurality of channels with the fluid prior to the processing of the semiconductor substrate; Including, the system.
32. 32. The system of claim 31, the second electrode includes a first annular segment and a second annular segment; the plurality of channels are disposed within an annular region of the dielectric layer beneath the first annular segment.
33. 32. The system of claim 31, the second electrode includes a first annular segment and a second annular segment; the plurality of channels are disposed within an annular region of the dielectric layer beneath the first annular segment; A portion of the dielectric layer separates the second electrode from the plurality of channels.
34. 32. The system of claim 31, the second electrode includes an outer electrode and an inner electrode; the outer electrode includes a first annular segment and a second annular segment; the plurality of channels are disposed within an annular region of the dielectric layer beneath the first annular segment; a portion of the dielectric layer separating the second electrode from the plurality of channels; The DC power supply is to the first annular segment through a first resistor; to the second annular segment via a second resistor; to the inner electrode via a third resistor; The system supplies the DC power.
35. 2. The substrate support assembly of claim 1, The fluid comprises a liquid, a gas, air, a fluorinated liquid, or a liquid metal selected from the group consisting of mercury and an alloy containing bismuth, antimony, gallium and / or indium.
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