Improved pedestal for a substrate processing system

Abstract

The substrate support has at least three pockets defined along the periphery of the substrate support, an edge gas groove positioned on the upper surface of the substrate support, and a first clamp groove positioned radially inward from the edge gas groove on the upper surface of the substrate support. Each pocket has a narrow portion and a wide portion positioned radially outward from the narrow portion. The edge gas groove is concentric with the substrate support. The edge gas groove intersects the narrow portion of each pocket. There are at least 30 through holes in the edge gas groove and at least one through hole in the narrow portion of each pocket.

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 359,474, filed Jul. 8, 2022. The application referenced above is hereby incorporated by reference in its entirety.

[0002] The present disclosure generally relates to a substrate processing system, and more specifically to a pedestal for a substrate processing system.

Background Art

[0003] The background description provided herein is for the purpose of generally presenting the content of the present disclosure. Within the scope described in this background art section, research by the inventors named at the present time, as well as aspects of the description that cannot be separately regarded as prior art at the time of filing, are not admitted as prior art against the present disclosure, whether explicitly or implicitly.

[0004] During the manufacture of a substrate such as a semiconductor wafer, an etching process and a deposition process can be performed in a processing chamber. The substrate is placed on a substrate support such as an electrostatic chuck (ESC) or a pedestal within the processing chamber. A process gas is introduced into the processing chamber, and in some examples, plasma is generated.

[0005] Some substrate supports may have components such as shadowing or carrier rings. For example, shadowing can be used to protect the outer edge of the substrate from deposition or etching. The shadowing may be raised to facilitate the transfer of the substrate onto the substrate support and then lowered. The inner diameter of the shadowing overlaps with the outer edge of the substrate. Conversely, a carrier ring can be used to raise and lower the substrate to facilitate transfer.

Summary of the Invention

[0006] A substrate support for a substrate processing system includes a base plate, at least one pocket defined on a first surface of the base plate, the at least one pocket having a recess configured to receive at least a portion of a carrier ring disposed on the first surface of the base plate, a first channel disposed through the base plate for supplying a process gas mixture having at least a first process gas and a second process gas to a backside edge of a substrate disposed on the substrate support, and a second channel disposed through the base plate for supplying one of the first process gas and the second process gas to at least one pocket defined within the first surface of the base plate independently of the first channel.

[0007] In another feature, the substrate support further includes a carrier ring. The carrier ring has at least one contact finger extending downwardly and radially inwardly from the carrier ring, the contact finger extending into at least one pocket when the carrier ring is in a lowered position. The at least one pocket has three pockets. The substrate support has an annular plenum defined radially inward of the at least one pocket in the base plate, the second channel being in fluid communication with the annular plenum, and the annular plenum being in fluid communication with the at least one pocket. The substrate support further includes at least one outlet channel extending from the annular plenum to the at least one pocket. The at least one outlet channel extends upwardly and radially outwardly from the annular plenum toward the at least one pocket.

[0008] In another feature, the second channel extends below at least one pocket, and at least one outlet channel extends upward from the second channel toward at least one pocket. The second channel is disposed above the first channel within the base plate. The second channel is disposed below the first channel within the base plate. The substrate support further has a third channel disposed through the base plate for supplying one of the first process gas and the second process gas to at least one pocket defined in the first surface of the base plate, independent of the first channel and the second channel. The second channel is disposed above the first channel within the base plate, and the third channel is disposed below the first channel within the base plate.

[0009] In another feature, the substrate support further has an annular plenum defined radially inward of at least one pocket in the base plate, the second channel is in fluid communication with the annular plenum, and the annular plenum is in fluid communication with at least one pocket via at least one first outlet channel. The third channel extends below at least one pocket. At least one second outlet channel extends upward from the third channel toward at least one pocket.

[0010] A system for supplying a process gas to a back edge of a substrate disposed on a substrate support includes a gas delivery system for supplying a process gas from a plurality of gas sources to the back edge of the substrate, and a controller for controlling the gas delivery system to supply a process gas mixture including at least a first process gas and a second process gas to the back edge via a first channel disposed through the substrate support, and to supply one of the first process gas and the second process gas to a pocket defined within the substrate support via a second channel independent of the first channel and disposed through the substrate support.

[0011] In another feature, the process gas mixture has argon and ammonia. The controller supplies one of the first process gas and the second process gas to the pocket through a third channel arranged through the substrate support, independent of the first channel and the second channel.

[0012] A substrate support for a substrate processing system includes a base plate, at least one clamp groove defined on a first surface of the base plate, at least one pocket defined on the first surface of the base plate, the at least one pocket having a recess configured to receive at least a portion of a carrier ring disposed on the first surface of the base plate, a first channel disposed through the base plate for supplying a process gas mixture having at least a first process gas and a second process gas from a first plenum to a backside edge of a substrate disposed on the substrate support and the at least one pocket, and a second channel disposed through the base plate, independent of the first channel and the second channel, for supplying one of the first process gas and the second process gas from a second plenum positioned radially inside the first plenum and radially outside at least one clamp groove to the backside edge of the substrate.

[0013] In another feature, the substrate support further has a third channel disposed through the base plate for supplying one of the first process gas and the second process gas to at least one pocket defined on the first surface of the base plate. The substrate support further has a recess defined between the first channel and the second channel on the first surface of the substrate support. The recess provides fluid communication between the first channel and the second channel on the first surface.

[0014] A method of supplying a process gas to a back edge of a substrate disposed on a substrate support includes supplying a process gas mixture including a first process gas and a second process gas to the back edge through a first channel disposed through the substrate support, and supplying one of the first process gas and the second process gas to a pocket defined in the substrate support through a second channel independent of the first channel and disposed through the substrate support.

[0015] In another feature, the process gas mixture has argon and ammonia. The method further includes supplying one of the first process gas and the second process gas to the pocket through a third channel disposed through the substrate support and independent of the first channel and the second channel.

[0016] In yet another feature, the substrate support has a base portion and a stem portion. The base portion has a plurality of plates defining a plurality of plenums within the base portion. The stem portion is coupled to the base portion. The stem portion has a plurality of conduits in fluid communication with the plurality of plenums.

[0017] In an additional feature, the base portion and the stem portion are made of a metallic material and are cylindrical. The stem portion has a smaller diameter than the base portion.

[0018] In an additional feature, the plurality of plenums are configured to supply one or more gases through an upper plate of the base portion during processing and to clamp a substrate to the upper plate using a vacuum clamp.

[0019] In an additional feature, a first plate of the plurality of plates is disposed between a second plate and a third plate of the plurality of plates and separates a first plenum and a second plenum of the plurality of plenums defined by the first, second, and third plates.

[0020] In an additional feature, the first plenum is configured to supply one or more gases around the edge of the substrate disposed on the upper plate through the upper plate among the plurality of plates during processing. The second plenum is configured to supply one or more gases to a plurality of pockets extending radially outward from the periphery of the base portion.

[0021] In an additional feature, the third plenum among the plurality of plenums is configured to supply gas radially outward from below the substrate through the upper plate during processing.

[0022] In an additional feature, the supply of one or more gases through the first and second plenums is controlled by respective mass flow controllers. The supply of gas through the third plenum is controlled using a pressure controller.

[0023] In an additional feature, each plenum of the plurality of plenums is separated from the other plenums of the plurality of plenums. A plurality of conduits are in fluid communication with the plurality of plenums respectively.

[0024] In an additional feature, the base portion has a plurality of pockets extending radially outward from the periphery of the base portion. The upper plate among the plurality of plates has a plurality of through holes in fluid communication with the plurality of pockets respectively. The plurality of through holes extend radially outward through the upper plate at an acute angle with respect to the axis perpendicular to the base portion.

[0025] In an additional feature, the upper plate has a plurality of concentric grooves. The plurality of plenums include a first, a second, and a third plenum in fluid communication with the plurality of concentric grooves respectively. The plurality of plenums include a fourth plenum in fluid communication with the plurality of through holes. The first, second, third, and fourth plenums are separated.

[0026] In an additional feature, the upper plate has a plurality of concentric grooves. The plurality of plenums each have first, second, and third plenums that are in fluid communication with the plurality of concentric grooves. The first, second, and third plenums are separated. The first, second, and third plenums are in fluid communication with a plurality of through-holes and one of the plurality of concentric grooves.

[0027] In an additional feature, the base portion has a plurality of pockets that extend radially outward from the periphery of the base portion.

[0028] In an additional feature, among the plurality of plates, the upper plate has a plurality of concentric grooves. The plurality of concentric grooves are each in fluid communication with a plurality of plenums within the base portion. One of the plurality of concentric grooves intersects the plurality of pockets near the radially inner end of the plurality of pockets.

[0029] In an additional feature, the plurality of concentric grooves include a first concentric groove having a first diameter, a second concentric groove having a second diameter smaller than the first diameter, and a third concentric groove having a third diameter smaller than the second diameter. The first diameter is larger than a fourth diameter of the substrate. The second diameter and the third diameter are smaller than the fourth diameter of the substrate.

[0030] In an additional feature, the upper plate among the plurality of plates further has a plurality of through-holes that are each in fluid communication with a plurality of pockets. The plurality of through-holes extend radially outward through the upper plate at an acute angle with respect to an axis perpendicular to the base portion.

[0031] In an additional feature, the plurality of plenums each have first, second, and third plenums that are in fluid communication with the plurality of concentric grooves. A fourth plenum among the plurality of plenums is in fluid communication with a plurality of through-holes. The first, second, third, and fourth plenums are separated and are each in fluid communication with a plurality of conduits.

[0032] In an additional feature, the fourth plenum is configured to supply heated gas to the plurality of through-holes.

[0033] In an additional feature, the plurality of plenums each have first, second, and third plenums that are in fluid communication with a plurality of concentric grooves. The first, second, and third plenums are separated and each are in fluid communication with a plurality of conduits. The first plenum is in fluid communication with a plurality of through-holes and one of the plurality of concentric grooves.

[0034] In an additional feature, the upper plate of the plurality of plates has a plurality of concentric grooves. The plurality of concentric grooves are each in fluid communication with a plurality of plenums within the base portion. One of the plurality of concentric grooves intersects the plurality of pockets near the radially inner ends of the plurality of pockets.

[0035] In an additional feature, the plurality of concentric grooves have a first concentric groove having a first diameter and a second concentric groove having a second diameter smaller than the first diameter. The first diameter is larger than a third diameter of the substrate. The second diameter is smaller than the third diameter of the substrate.

[0036] In an additional feature, the upper plate of the plurality of plates further has a plurality of through-holes each in fluid communication with a plurality of pockets. The plurality of through-holes pass radially outward through the upper plate and extend at an acute angle with respect to an axis perpendicular to the base portion.

[0037] In an additional feature, the plurality of plenums each have first and second plenums that are in fluid communication with a plurality of concentric grooves. The plurality of plenums have a third plenum that is in fluid communication with a plurality of through-holes. The first, second, and third plenums are separated and each are in fluid communication with a plurality of conduits.

[0038] In an additional feature, the plurality of plenums each have first and second plenums that are in fluid communication with a plurality of concentric grooves. The first plenum is in fluid communication with a plurality of through-holes and a first concentric groove. The first and second plenums are separated and each are in fluid communication with a plurality of conduits.

[0039] In an additional feature, the plurality of plates includes a first plate coupled to the stem portion. The second plate has a first surface joined to the first plate. The second plate has a circular slot in the second surface. The third plate is joined to the second surface of the second plate. The fourth plate is joined to the third plate. The fifth plate is disposed within the circular slot and joined to the second plate and the third plate. The second plate has a first plenum of the plurality of plenums. The first plenum is defined by a first annular groove and a first set of radial grooves extending radially inward from the first annular groove and is connected to a first conduit of the plurality of conduits. The third plate has a second plenum of the plurality of plenums on a first surface joined to the fifth plate. The second plenum is defined by a second set of grooves extending radially inward from a first set of through holes and is connected to a second conduit of the plurality of conduits. The diameter of the fifth plate is equal to the inner diameter of the first annular groove. The diameter of the fifth plate is larger than the diameter of the circle on which the first set of through holes is disposed.

[0040] In an additional feature, the third plate has a third plenum of the plurality of plenums on a second surface joined to the fourth plate. The third plenum is defined by a second annular groove, a third set of grooves extending radially outward from the second annular groove, and a fourth set of grooves extending radially inward from the second annular groove and is connected to a third conduit of the plurality of conduits.

[0041] In an additional feature, the fourth plate has a first groove and a second groove. The first and second grooves are concentric. The first groove has a larger diameter than the second groove and also has a larger diameter than the substrate supported by the substrate support. The third and fourth plates have a second set of through-holes that provide fluid communication between the first plenum and the first groove. The fourth plate has a third set of through-holes that extend radially outward through the upper plate and at an acute angle to an axis perpendicular to the base portion. The third set of through-holes provides fluid communication with the second plenum. The fourth plate has a fourth set of through-holes that provide fluid communication with the third set of grooves, the second groove, and the third plenum.

[0042] In an additional feature, the base portion has a plurality of pockets that extend radially outward from the periphery of the base portion. Each of the third set of through-holes provides fluid communication with the plurality of pockets. The first groove intersects the plurality of pockets in the vicinity of the radially inner ends of the plurality of pockets.

[0043] In an additional feature, the plurality of plates includes a first plate coupled to the stem portion, a second plate joined to the first plate, and a third plate joined to the second plate. The second plate has a first plenum of the plurality of plenums. The first plenum is defined by an annular groove and a set of radial grooves that extend radially inward from the annular groove and is connected to a first conduit of the plurality of conduits. The third plate has a circular groove and a set of through-holes that provide fluid communication with the first plenum.

[0044] In an additional feature, the base portion has a plurality of pockets that extend radially outward from the periphery of the base portion. The circular groove intersects the plurality of pockets in the vicinity of the radially inner ends of the plurality of pockets. The diameter of the circular groove is larger than the diameter of the substrate supported on the third plate.

[0045] In an additional feature, the upper plate among the plurality of plates has a plurality of clamp grooves. One of the plurality of plenums is in fluid communication with the plurality of clamp grooves and one of the plurality of conduits. The plurality of clamp grooves are configured to clamp a substrate to the upper plate using a vacuum.

[0046] In an additional feature, the plurality of clamp grooves have concentric grooves and radial grooves connected to the concentric grooves. The depth of at least one of the concentric grooves and the radial grooves is greater than the width of at least one of the concentric grooves and the radial grooves.

[0047] In an additional feature, the upper plate has a plurality of through holes arranged as a plurality of concentric circles within the plurality of radial grooves.

[0048] In an additional feature, at least one edge of the concentric grooves and the radial grooves is rounded.

[0049] In an additional feature, the upper plate among the plurality of plates has a first groove and a second groove that are in fluid communication with the first and second plenums among the plurality of plenums. The first and second grooves are concentric. The first groove has a larger diameter than the second groove and also has a larger diameter than the substrate. The base portion has a plurality of pockets extending radially outward from the periphery of the base portion. The first groove intersects the plurality of pockets near the radially inner ends of the plurality of pockets. The inner diameter of the first groove is closer to the radially inner ends of the plurality of pockets than the second groove.

[0050] In an additional feature, the base portion has a plurality of pockets extending radially outward from the periphery of the base portion. Each of the plurality of pockets has a slot in its outer wall. The slots are positioned away from the brazing interface of the plurality of plates.

[0051] In an additional feature, the height of the slot is smaller than the thickness of any one of the plurality of plates in which the slot is formed.

[0052] In an additional feature, the substrate support has a heater coil disposed on one of a plurality of plates. The heater coil has at least 3 turns that are uniformly distributed from the center of the base portion to the outer diameter of the base portion.

[0053] In an additional feature, the substrate support has a heater coil disposed on the base portion. The heater coil is connected to a power source through the stem portion by a pair of insulated conductors. A temperature sensor is disposed on the base portion. The temperature sensor is connected to a circuit through an additional conduit disposed through the stem portion. The plurality of conduits, the pair of conductors, and the additional conduit pass through an opening in the stem portion.

[0054] In yet another feature, the substrate support has at least 3 pockets defined along the periphery of the substrate support, an edge gas groove positioned on the upper surface of the substrate support, and a first clamp groove positioned radially inward from the edge gas groove on the upper surface of the substrate support. Each pocket has a narrow portion and a wide portion positioned radially outward from the narrow portion. The edge gas groove is concentric with the substrate support. The edge gas groove intersects the narrow portion of each pocket. There are at least 30 through holes in the edge gas groove and at least 1 through hole in the narrow portion of each pocket.

[0055] In an additional feature, the substrate support has at least 1 inclined hole positioned in at least 1 narrow portion of at least 3 pockets and a purge gas groove positioned between the edge gas groove and the first clamp groove on the upper surface of the substrate support. The at least 1 inclined hole is connected to a gas delivery conduit.

[0056] In an additional feature, the edge gas groove, the purge gas groove, and the first clamp groove are concentric.

[0057] In an additional feature, for at least one of the at least three pockets, the inclined holes are positioned on the radially inner sidewall of the narrow portion of each pocket, and the radially inner sidewall is the surface of the pocket closest to the center of the substrate support.

[0058] In an additional feature, the radially inner sidewall is perpendicular to the bottom surface of each pocket.

[0059] In an additional feature, the inclined holes are positioned above at least 25% of the height of the radially inner sidewall of the narrow portion of each pocket, and this height is measured from the bottom surface of each pocket.

[0060] In an additional feature, the inclined holes are positioned above at least 50% - 75% of the height of the radially inner sidewall of the narrow portion of the pocket.

[0061] In an additional feature, the gas delivery conduit has a central axis that is not perpendicular to the radially inner sidewall of the narrow portion of each pocket.

[0062] In an additional feature, the central axis of the gas delivery conduit forms an acute angle with the radially inner sidewall of the narrow portion of the pocket.

[0063] In an additional feature, the acute angle is between 20 degrees and 80 degrees.

[0064] In an additional feature, the acute angle is between 30 degrees and 70 degrees.

[0065] In an additional feature, the acute angle is between 40 degrees and 60 degrees.

[0066] In an additional feature, the purge gas groove includes one or more through - holes.

[0067] In an additional feature, the purge gas groove and the first clamp groove have an inwardly rounded portion that is radially aligned with the inner end of each pocket.

[0068] In an additional feature, the substrate support further has a plurality of clamping grooves positioned radially inward from the first clamping groove. The plurality of clamping grooves include a plurality of radial clamping grooves and one or more concentric clamping grooves. At least one of the plurality of radial clamping grooves intersects at least one concentric clamping groove and the first clamping groove.

[0069] In an additional feature, the plurality of radial clamping grooves close to the central portion of the substrate support have a plurality of through holes arranged in a circular array.

[0070] In an additional feature, the plurality of radial clamping grooves close to the central portion of the substrate support have one or more through holes along each of the plurality of radial clamping grooves.

[0071] In an additional feature, the diameter of one or more through holes occupies 55% - 90% of the width of each respective radial clamping groove.

[0072] In an additional feature, at least one of the three pockets is defined in the ear portion of the substrate support. The ear portion of the substrate support includes a slot defined on the outer surface of the ear portion. The slot is completely defined within a single plate.

[0073] In an additional feature, it further has a plurality of ceramic springs disposed on the upper surface of the substrate support.

[0074] In an additional feature, the substrate support further has a plurality of clamping grooves positioned radially inward from the first clamping groove. The plurality of clamping grooves include a plurality of radial clamping grooves and one or more concentric clamping grooves. At least one of the plurality of radial clamping grooves intersects one or more concentric clamping grooves and the first clamping groove.

[0075] In an additional feature, the plurality of radial clamping grooves close to the central portion of the substrate support have a plurality of through holes arranged in a circular array.

[0076] In an additional feature, a plurality of radial clamping grooves proximate to the central portion of the substrate support have one or more through-holes along each of the plurality of radial clamping grooves.

[0077] In an additional feature, the diameter of one or more through-holes occupies 55% to 90% of the width of each respective radial clamping groove.

[0078] In an additional feature, at least one of the three pockets is defined in the ear portion of the substrate support. The ear portion of the substrate support includes a slot defined on the outer surface of the ear. The slot is completely defined within a single plate.

[0079] A further scope of application of the present disclosure will become apparent from the detailed description of the invention, the claims and the drawings. The detailed description of the invention and the specific examples are only intended for explanation and are not intended to limit the scope of the present disclosure.

Brief Description of the Drawings

[0080] The present disclosure will be more fully understood with reference to the detailed description of the invention and the accompanying drawings.

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[0111] In the drawings, reference numerals may be reused to identify similar and / or identical elements.

Best Mode for Carrying Out the Invention

[0112] In a substrate processing system using components such as shadowing, carrier ring, and combined shadow / carrier ring, the substrate support may have various features to facilitate the interaction and alignment between the component and the substrate support. For example, the first (upper) surface of the substrate support may have one or more recesses or pockets (e.g., defined by a ceramic layer, a base plate, etc.). In some examples, the pocket is configured to accommodate the features of the carrier ring in the lowered position. For example, the pocket may correspond to the substrate receiving position of the carrier ring (e.g., the position of the fingers of the carrier ring configured to receive the substrate). In another example, the pocket has alignment features for aligning the shadowing, carrier ring, and / or other components with the substrate support.

[0113] In some examples, the pocket may cause process non-uniformity. For example, the deposition thickness on the substrate may decrease at the position corresponding to the pocket. In some examples, the pocket impedes the flow of the process gas containing a purge gas (e.g., argon, ammonia (NH3), etc.). The substrate support may be configured to supply the process gas containing the purge gas to the backside edge of the substrate to improve the uniformity of deposition. However, even then, the pocket still impedes the flow of the process gas and causes deposition non-uniformity. For example, supplying the deposition process gas to the backside edge of the substrate may increase the deposition at the position corresponding to the pocket, but deposition non-uniformity may be caused at other positions along the edge of the substrate.

[0114] The substrate support according to the present disclosure has two or more channels configured to supply different flows of different process gases or a process gas mixture containing a purge gas to the pockets. For example, the substrate support may have a plurality of independent plenums and / or channels. In one example, the first channel supplies a process gas mixture having a plurality of process gases (e.g., argon and ammonia) containing a purge gas to the backside edge of the substrate. The second channel supplies only one type of process gas (e.g., argon) to the pocket. In some examples, the third channel supplies another process gas (e.g., ammonia) to the pocket (independently of the second channel). In this way, it becomes possible to independently control the supply of the process gas mixture and the individual process gases in the process gas mixture containing the purge gas to different regions of the backside edge of the substrate.

[0115] Referring to FIG. 1, an example of a substrate processing system 100 having a substrate support 104 (e.g., a pedestal configured for CVD and / or ALD deposition) according to the present disclosure is shown. The substrate support 104 is disposed within a processing chamber 108. During processing, a substrate 112 is placed on the substrate support 104. For example, deposition is performed on the substrate 112. The substrate 112 is removed and one or more additional substrates are processed.

[0116] The gas delivery system 120 has gas sources 122-1, 122-2,..., and 122-N (collectively gas source 122) connected to valves 124-1, 124-2,..., and 124-N (collectively valves 124) and mass flow controllers 126-1, 126-2,..., and 126-N (collectively MFC 126). The MFC 126 controls the flow of gas from the gas source 122 to a manifold 128 where the gases are mixed. The output of the manifold 128 is supplied to a manifold 136 via an optional pressure regulator 132. The output of the manifold 136 is input to a gas delivery device such as a multi-injector showerhead 140. Although the manifolds 128 and 136 are shown, a single manifold may be used.

[0117] In some examples, the temperature of the substrate support 104 may be controlled using the resistive heater 144. To measure the pressure, pressure sensors 152, 154 may be disposed within the manifold 128 or the manifold 136, respectively. The valve 156 and the pump 158 may be used to discharge reactants from the processing chamber 108 and / or to control the pressure within the processing chamber 108.

[0118] The controller 160 includes a dose controller 162 that controls the dose amount provided by the multi-injector showerhead 140. The controller 160 also controls the gas delivery from the gas delivery system 120. The controller 160 controls the pressure within the processing chamber and / or the discharge of reactants using the valve 156 and the pump 158. The controller 160 controls the temperature of the substrate support 104 and the substrate 112 based on temperature feedback (e.g., feedback from a sensor (not shown) within the substrate support and / or a sensor (not shown) that measures the temperature of the refrigerant).

[0119] Although described as being configured to perform a deposition process, the substrate processing system 100 may be configured to perform an etching process. In some examples, the substrate processing system 100 may be configured to perform etching on the substrate 112 within the same processing chamber 108 as the deposition process. Accordingly, the substrate processing system 100 may include an RF generation system 164 (e.g., a voltage source, a current source, etc.) configured to generate RF power and supply it to one of a lower electrode (e.g., the base plate of the substrate support 104 as shown) and an upper electrode (e.g., the showerhead 140). The other of the lower electrode and the upper electrode may be DC grounded, AC grounded, or floating.

[0120] Merely by way of example, the RF generation system 164 may include an RF generator 166 configured to generate an RF voltage supplied by a matching and distribution network 168 to generate plasma within the processing chamber 108 to etch the substrate 112. In another example, the plasma may be generated inductively or remotely. However, as shown for illustrative purposes, the RF generation system 164 corresponds to a capacitively coupled plasma (CCP) system, but the principles of the present disclosure may be implemented by other suitable systems, such as, merely by way of example, a transformer coupled plasma (TCP) system, a CCP cathode system, a remote microwave plasma generation / delivery system, etc.

[0121] The substrate support 104 has a carrier ring 170. In some examples, the inner edge of the carrier ring 170 overlaps the outer edge of the substrate 112. The carrier ring 170 may be raised and lowered (e.g., using lift pins and respective actuators not shown in FIG. 1). For example, the carrier ring 170 has one or more (e.g., three evenly spaced) contact fingers 174 extending downward from the carrier ring 170 and radially inwardly toward the substrate 112.

[0122] As shown, the carrier ring 170 is in the lowered position. In the lowered position, the contact fingers 174 are disposed in corresponding pockets 178 defined within the upper surface of the substrate support 104. When moved to the raised position, the contact fingers 174 engage the outer edge of the substrate 112 and lift the substrate 112 to facilitate transfer. Conversely, when the carrier ring 170 is in the raised position, the substrate 112 is transferred to the contact fingers 174. Then, when the carrier ring 170 is lowered, the substrate 112 descends onto the substrate support 104.

[0123] The substrate support 104 according to the present disclosure has two or more channels configured to supply a separate flow of different process gases, or a process gas mixture, to the pockets 178, as will be described in more detail below.

[0124] Referring now to FIGS. 2A, 2B, 2C, and 2D, an exemplary substrate support 200 according to the present disclosure is shown in more detail. FIGS. 2A and 2B are cross-sectional views of an example of the substrate support 200. FIG. 2C is a plan (looking down) view of the substrate support 200 of FIG. 2A.

[0125] The base plate 204 of the substrate support 200 has one or more recesses or pockets 208. The base plate 204 may be conductive (e.g., made of a metal such as aluminum). In some examples, the base plate 204 may have other materials such as a ceramic material. The pockets 208 are defined in a first (e.g., upper) surface 212 of the substrate support 200 / base plate 204. As shown in FIG. 2C, three pockets 208 are evenly distributed along the outer edge of the base plate 204. As an example, the pockets 208 are circumferentially spaced apart at 120-degree intervals. In some examples, one of the pockets 208 may be offset from an adjacent pocket by an interval greater than or less than 120 degrees (e.g., a 10-degree offset). In other examples, the base plate 204 has fewer than three or more than three pockets 208 that are evenly or unevenly distributed.

[0126] The pockets 208 are configured to receive at least a portion of a carrier ring 216 supported in a lowered position on the substrate support 200. For example, the carrier ring 216 has contact fingers 220 that extend downwardly from the carrier ring 216 and radially inwardly toward a substrate 224 disposed on the substrate support 200. When in the lowered position, the contact fingers 220 are aligned with and disposed within their respective pockets 208. In some examples, the inner edge of the carrier ring 216 overlaps the outer edge of the substrate 224. The carrier ring 216 is not shown in FIG. 2C.

[0127] The carrier ring 216 may be raised and lowered using one or more lift pins 228 and respective actuators 232. The actuators 232 may respond to control signals received from a controller (e.g., controller 160). In one example, the outer edge of the carrier ring 216 may extend radially outside the outer edge of the base plate 204. The lift pins 228 are aligned with the outer edge of the carrier ring 216 that is outside the outer edge of the base plate 204. In another example, the carrier ring 216 has tabs 236 that extend radially outward from the carrier ring 216. The tabs 236 extend outward from a position corresponding to the lift pins 228. Thus, the lift pins 228 engage the tabs 236 to raise and lower the carrier ring 216. When in the illustrated lowered position (e.g., during processing of the substrate 224), the contact fingers 220 are disposed within the pockets 208.

[0128] The substrate support 200 according to some examples of the present disclosure has two or more plenums or channels 240 configured to supply respective different flows of different process gases, or a process gas mixture, to the pockets 208. For example, the substrate support 200 has a first channel 240-1 and a second channel 240-2 (collectively referred to as channels 240). The first channel 240-1 supplies a process gas mixture having a plurality of process gases (e.g., argon and ammonia) to the back edge of the substrate 224. The second channel 240-2 supplies only one type of process gas (e.g., argon) to the pockets 208. The first channel 240-1 and the second channel 240-2 may also be referred to as the first gas channel 240-1 and the second gas channel 240-2, respectively. In this way, it becomes possible to independently control the supply of the process gas mixture and the individual process gases in the process gas mixture to different regions of the back edge of the substrate 224.

[0129] In one example, a gas mixture having a plurality of process gases (e.g., argon and ammonia) is supplied through a first inlet channel 242 to a first channel 240-1. The first channel 240-1 supplies the gas mixture upwardly through a first outlet channel 244 toward the backside edge of the substrate 224. For example, the first outlet channel 244 is an annular channel surrounding the backside edge of the substrate 224. On the other hand, one of the process gases (e.g., argon) is independently supplied through a second inlet channel 246 to a second channel 240-2. The second channel 240-2 supplies the process gas to the pockets 208 through a plurality of second outlet channels 248.

[0130] As shown in FIG. 2A, the second channel 240-2 is disposed above the first channel 240-1. The second channel 240-2 supplies an annular plenum 250 located radially inside the pocket 208. The second outlet channels 248 extend upwardly and outwardly (i.e., inclined) from the annular plenum 250 toward the pockets 208. As shown in FIG. 2B, in another example, the second channel 240-2 is disposed below the first channel 240-1. The second channel 240-2 supplies an annular plenum 252 located below the pocket 208. The second outlet channels 248 extend upwardly from the annular plenum 252 toward the pockets 208.

[0131] The base plate 204 may have a first (e.g., lower) portion 260 and a second (e.g., upper) portion 262. For example, the first portion 260 and the second portion 262 correspond to a first plate and a second plate. The first portion 260 and the second portion 262 may be made of the same or different materials. By using the individual first portion 260 and second portion 262 to construct the base plate 204, it may be easier to form the channel 240 within the base plate 204. For example, the channel 240 may be machined on the upper surface of the first portion 260. Thereafter, the base plate 204 is formed by attaching the first portion 260 and the second portion 262 to each other (e.g., brazed, welded, etc.). Only the first portion 260 and the second portion 262 are shown, but the base plate 204 may have more than two portions attached to each other. For example, each of the channels 240 may be included in different portions or plates of the base plate 204. For example, the first channel 240-1 is defined on the upper surface of the first portion 260, and the second channel 240-2 is defined on the lower surface of the second portion 262.

[0132] FIG. 2D shows an example of a substrate support 200 having three channels 240. In this example, the second channel 240-2 is disposed above the first channel 240-1. The second channel 240-2 supplies an annular plenum 250 located radially inside the pocket 208. The second outlet channel 248 extends upward and outward from the annular plenum 250 toward the pocket 208. The third channel 240-3 is disposed below the first channel 240-1. The third inlet channel 270 supplies process gas to the third channel 240-3. The third channel 240-3 supplies an annular plenum 272 located below the pocket 208. The third outlet channel 274 extends upward from the annular plenum 272 toward the pocket 208.

[0133] In the example shown in FIG. 2D, the gas mixture can be supplied to the back edge of the substrate 224 and the pocket 208 through three independent channels. As an example, the first channel 240-1 supplies a process gas mixture having a plurality of process gases (e.g., the first and second gases such as argon and ammonia) to the back edge of the substrate 224. In other words, the first channel 240-1 supplies the process gas mixture to the entire back edge (e.g., through the annular outlet channel 244). The process gas mixture may be continuously supplied during the deposition process or process.

[0134] The second gas channel 240-2 supplies a subset of the process gases of the gas mixture (e.g., only one type) to the pocket 208. In other words, the gas supplied by the second gas channel 240-2 corresponds to one of the gases in the gas mixture supplied by the first gas channel 240-1. In this example, the second gas channel 240-2 supplies the first process gas (e.g., ammonia) to the pocket 208. The second gas channel 240-2 may supply the first process gas to the pocket 208 continuously and / or at periodic intervals.

[0135] The third gas channel 240-3 supplies another subset of the process gases of the gas mixture to the pocket 208. The gas supplied by the third gas channel 240-3 may be the same as or different from the gas supplied by the second gas channel 240-2. In this example, the third gas channel 240-3 supplies the second process gas (e.g., argon) to the pocket 208. The third gas channel 240-3 may supply the second process gas to the pocket 208 continuously and / or at periodic intervals.

[0136] The third gas channel 240-3 may supply the second process gas to the pocket 208 either simultaneously with or at a different timing from when the second gas channel supplies the first process gas to the pocket 208. For example, the second gas channel 240-2 supplies the first process gas to the pocket 208 during the deposition process in order to improve the uniformity of deposition at the edge of the substrate 224. On the other hand, the third gas channel 240-3 supplies the second process gas as a purge gas for purging the pocket 208 following the deposition process.

[0137] The supply (flow) of the process gas through the channel 240 is controlled using controllers such as the controller 160 and the dose controller 162. The process gas supplied by the channel 240 may be the same as or different from the process gas supplied by the shower head 140. Therefore, the controller 160 may be configured to control the supply of the process gas from the same gas delivery system 120 to the channel 240. In another example, the controller 160 may control the supply of the process gas from a different gas delivery system (e.g., different gas source, valve, etc.) to the channel 240.

[0138] Figures 2E, 2F, and 2G show other configuration examples of the substrate support 200. For simplicity, some components (e.g., the inlet channel, the actuator 232, and the pins 228, etc.) are not shown. In these and other examples, the substrate support 200 may have a clamp groove 276 defined in the upper surface 212 below the substrate 224. A clamp gas for clamping the substrate 224 to the substrate support 200 is supplied to the clamp groove 276. Generally, the gas pressure in the clamp groove 276 is lower than the pressure in the process volume in the processing chamber (i.e., the chamber pressure above the substrate 224). As a result, the process gas may leak under the back side of the substrate 224 or into the clamp groove 276, etc.

[0139] As shown in FIGS. 2E, 2F, and 2G, the substrate support 200 has dedicated purge plenums 278-1 and 278-2 (collectively referred to as purge plenum 278). Purge plenum 278-1 may be disposed radially outward of the outer edge of the substrate to supply process gas or purge gas (e.g., argon) through respective channels to the backside edge of the substrate 224 and the pocket 208. For example, purge plenum 278-1 may be configured similarly to the first channel 240-1 described above.

[0140] On the other hand, purge plenum 278-2 is disposed radially inward of purge plenum 278-1 and the outer edge of the substrate 224 and radially outward of the clamp groove 276. Purge gas (e.g., argon) is independently supplied to purge plenum 278-2 and is supplied upward through purge channel 280. The purge gas flows from purge channel 280 outward to the backside edge of the substrate 224 and inward to the clamp groove 276. Thus, the purge gas supplied to purge plenum 278-2 prevents process gas from flowing under the backside edge of the substrate 224 and into the clamp groove 276.

[0141] The pressure of the purge gas supplied to the purge plenum 278 can be varied with respect to the chamber pressure. For example, purge plenum 278-2 may supply purge gas at a pressure greater than the chamber pressure. In other examples, purge plenum 278-2 provides purge gas at a pressure less than the chamber pressure.

[0142] As shown in FIGS. 2E and 2G, the substrate support 200 has another plenum 282 disposed radially inward of the purge plenum 278-1. The plenum 282 is arranged to supply an individual flow of purge gas and / or process gas to the pocket 208. For example, the plenum 282 is configured similarly to the second channel 240-2, the second outlet channel 248, and the annular plenum 250 described above. On the other hand, as shown in FIG. 2F, the purge plenum 278-1 supplies gas to the pocket 208 via both the outlet channels 284 and 286.

[0143] As shown in FIG. 2G, the upper surface 212 of the substrate support 200 has an annular recess or channel 290 between the purge plenum 278-1 and the purge plenum 278-2. The channel 290 enables fluid communication between the purge plenum 278-1 and the purge plenum 278-2 on the upper surface 212. As a result, the flow of the outward purge gas from the purge channel 280 to the back edge of the substrate 224 increases, thereby reducing the possibility that the substrate support 200 detaches from the substrate 224. Further, the supply of the purge gas from the purge plenum 278-2 to the pocket 208 increases. The depth of the channel 290 can be changed to control the desired amount of purge gas flow.

[0144] FIG. 3 shows the steps of an exemplary method 300 for supplying a gas mixture to the back edge of a substrate disposed on a substrate support according to the present disclosure. For example, the method 300 may be implemented by a controller 160, a gas delivery system 120, etc. At 304, the substrate is placed on the substrate support for processing (e.g., a deposition process). For example, the substrate is transferred to a carrier ring in a raised position, and the carrier ring is lowered so that the substrate descends onto the substrate support.

[0145] At 308, a process (e.g., a deposition process) is started. At 312, a deposition process gas mixture is supplied to the processing chamber via a gas distribution device (e.g., a showerhead). At 316, method 300 determines whether to supply the process gas to the backside edge of the substrate. For example, the process gas may be supplied continuously throughout the deposition process or only at regular intervals to the backside edge. In one example, the process gas is supplied in a pulsed manner, during intermittent periods during the deposition process, conditionally (e.g., in response to the process parameters meeting a certain criterion), etc., to the backside edge. If it is to be supplied, method 300 proceeds to 320. If not, method 300 proceeds to 324.

[0146] At 324, method 300 determines whether the deposition process is complete. If it is complete, method 300 ends. If not, method 300 proceeds to 312.

[0147] At 320, the process gas is supplied to the backside edge of the substrate via a first channel (e.g., the first channel 240-1). At 328, method 300 determines whether to supply the process gas to the pocket via a second channel (e.g., the second channel 240-2). For example, the process gas may be supplied continuously throughout the deposition process or only at regular intervals via the second channel 240-2 to the pocket 208. If it is to be supplied, method 300 proceeds to 332. If not, method 300 proceeds to 324.

[0148] At 332, one or more process gases are supplied to the back edge of the substrate through the second channel 240-2. In one example, one type of the process gases supplied through the first channel 240-1 is supplied to the pocket 208 through the second channel 240-2. In another example, one type of the process gases supplied through the first channel 240-1 is supplied to the pocket 208 through the second channel 240-2, and another type of the process gases supplied through the first channel 240-1 is supplied to the pocket 208 through the third channel (for example, the third channel 240-3).

[0149] Further examples of pedestal designs are shown and described below with reference to FIGS. 4A-25B. For example, pedestals having a plurality of separated plenums are shown and described with reference to FIGS. 4A-12. In addition to the separated plenums, the pedestal has a number of features that provide various advantages, the summary of which is shown below and the details of which will be described later. Additional examples of pedestal designs having various combinations of these plenums and features are shown and described with reference to FIGS. 13-25B. An example of a substrate processing system that can use any of the pedestal designs described herein is shown and described with reference to FIG. 26. The remaining figures show the arrangement of conduits for supplying gas to the plenums in more detail.

[0150] Some of the pedestal designs described below are similar to those described above with reference to FIGS. 1-3 and are shown and described in more detail below. For example, the pedestal designs shown in FIGS. 2E and 2F are shown in more detail in FIGS. 5 and 13, respectively. Any single feature or combination of features shown and described with reference to FIGS. 1-3 is implementable in the examples shown and described with reference to FIGS. 4-25. The pedestals described herein are generally also referred to as substrate supports.

[0151] Put simply, the following advantages are obtained due to the features of the pedestal described below. In some applications, the processed substrate shows evidence of deposition on the back side (i.e., the underside of the substrate) placed on the upper surface of the pedestal. In particular, back-side deposition is seen in regions where the upper surface of the pedestal has grooves (e.g., vacuum clamping grooves) and in regions having pockets that support a carrier ring for transporting the substrate during substrate transfer. One way to mitigate this back-side deposition problem is to supply edge gas through the grooves on the upper surface of the pedestal so that the edge gas flows radially outward from under the substrate. The radially outward gas flow prevents the diffusion of process gas into the region under the substrate, thereby preventing back-side deposition and minimizing corrosion of the radially inner portion of the upper surface of the pedestal by process chemicals.

[0152] Furthermore, various components of the pedestal may cause cold spots and temperature non-uniformities on the substrate. For example, the pocket region may cause a cold spot on a portion of the substrate above the pocket region. To prevent cold spots, the size of the pocket region can be reduced (e.g., the pocket can be recessed radially outward). In addition, to improve the process uniformity on the substrate at a position above the pocket region of the substrate, it is also possible to supply gas to the pocket through an independent plenum.

[0153] Furthermore, the gas supplied into the pocket through the independent plenum may be heated to locally increase the temperature of the substrate in the region directly above the pocket. This improves the temperature non-uniformity of the substrate in the region directly above the pocket and reduces cold spots. For example, the temperature of the gas (e.g., the power supplied to the heater used for heating the gas) may be selected based on the thickness of the wafer measured during substrate processing. Additionally, the inner diameter of the grooves on the upper surface of the pedestal that supply edge gas can be increased to reduce the overhang of the substrate above the grooves, thereby improving the non-uniformity at the edge of the substrate.

[0154] Furthermore, on the upper surface of the pedestal, ceramic springs are generally used to support the substrate before clamping. The ceramic springs can also cause cold spots on a portion of the substrate above the ceramic springs. In some examples, the ceramic springs can be removed to eliminate the cold spots caused by the ceramic springs. Other causes of cold spots include circular cutouts near the center of the upper surface of the pedestal that are provided for vacuum clamping. The pedestals described below eliminate these cutouts. Instead, the clamping grooves of these pedestals are narrow in width and large in depth in order to accommodate a plurality of holes for vacuum clamping without using cutouts. The narrow width of the clamping groove can minimize the cold spots generated on the substrate by the clamping groove.

[0155] In some examples, the clamping grooves are rounded to reduce the adverse effects of materials accumulated along the edges of the clamping grooves due to the reaction between the upper surface of the pedestal and the process chemicals. For example, the deposits along the edges of the clamping grooves tend to grow and lift the substrate. This affects the clamping of the substrate and causes non-uniformity problems. By rounding the clamping grooves, even when materials accumulate along the edges of the clamping grooves, there is a gap between the substrate and the deposits, so the influence of the deposits on the clamping of the substrate can be prevented, thereby preventing the process gas from leaking into the area under the substrate and damaging the clamping of the substrate. Therefore, the rounded grooves help prevent process variations due to surface irregularities caused by materials accumulated on the upper surface of the pedestal.

[0156] Furthermore, since the heaters embedded in the substrate generally tend to be sparse (i.e., including coils with only 2 or 3 turns that are not uniformly distributed throughout the radius of the pedestal), temperature non-uniformity occurs in the substrate. Instead, the pedestals described below have high-density heaters (i.e., including coils with more than 3 turns). Also, the heater coils are uniformly distributed in the radial direction throughout the pedestal, thereby improving the radial temperature uniformity of the substrate.

[0157] Also, the pedestal is generally formed by brazing a plurality of plates. The pocket has slots in which a nut plate and a washer are arranged to fix the wheel block assembly within the pocket (see FIGS. 20A and 20B). The wheel block assembly receives and supports a carrier ring - substrate holder assembly that is used to transfer a substrate between stations. (See FIGS. 20A and 20B). When a slot is formed at the boundary where two plates are brazed (i.e., at the center of the brazing surface), the contact area between the two plates is reduced by the slot, so the brazing joint force between the two plates is reduced. Further, the washer tends to expand due to corrosion or heat, thereby causing the pocket to peel off.

[0158] Instead, in the pedestal described below, the slot in the pocket is formed and positioned away from the brazing interface of the plates, so that the slot is not located at the interface where the two plates are brazed (i.e., the slot is not at the center of the brazing surface). Therefore, a larger area of the plate can be provided for brazing the plates, and as a result, the joint force between the plates is increased. Further, when the washer expands, the mechanical force due to the expansion is smaller than the joint force that keeps the plates in the joined state, so peeling of the pocket can be prevented. These and other features of the pedestal of the present disclosure will be described in detail below.

[0159] Throughout the following description of the pedestal shown in FIGS. 4A - 25B, an axis parallel to the plane on which the pedestal plates are mounted is called the horizontal axis or the x - axis shown in FIGS. 4A - 22B, and an axis perpendicular to the plane on which the pedestal plates are mounted is called the vertical axis, the pedestal axis, or the z - axis shown in FIGS. 4A - 22B.

[0160] Figures 4A - 12 show a pedestal 400 having a plurality of separated plenums and other features. Figure 4A shows a perspective view of the pedestal 400. Figures 4B and 4C show exploded perspective views of the pedestal 400 shown in Figure 4A. In Figures 4A - 4C, various features of the pedestal 400 can be seen. These features will be briefly described first with reference to Figures 4A - 4C and then described in detail with reference to Figures 5 - 12.

[0161] In Figures 4A - 4C, the pedestal 400 is made of a metallic material (e.g., aluminum or an alloy). In some examples, the pedestal 400 may be made of other materials such as a ceramic material. The pedestal 400 has a base portion 402 and a stem portion 404. The base portion 402 is generally cylindrical and extends radially along the x - axis. The stem portion 404 is also generally cylindrical and has a smaller diameter than the base portion 402. The stem portion 404 is coupled to the bottom of the stem portion 404 near the center of the base portion 402. The stem portion 404 extends along the z - axis. The stem portion 404 is hollow and houses a plurality of conduits described below.

[0162] The wall of the stem portion 404 is thick enough to provide sufficiently high creep resistance at high process temperatures. The creep resistance of a material is its ability to resist creep, which is the tendency of a material to slowly deform when subjected to a high level of stress over a long period of time. Creep deformation generally occurs when a material is stressed at a temperature near its melting point. Creep resistance is generally defined by the amount of creep that occurs when a constant strain is applied to a material over a certain period of time. In other words, creep resistance is defined as the level of stress required to produce a nominal strain (e.g., 0.1%, 0.2%, or 0.5%) over a certain period (e.g., 100,000 hours). Creep resistance is affected by factors such as the properties of the material, the length of time the material is subjected to the stress factor, the temperature at which the material is subjected to the stress factor, and the strength of the stress factor (e.g., the thermal load applied to the stem portion 404 during substrate processing). Therefore, the material and the thickness of the material of the stem portion 404 are selected to provide sufficiently high creep resistance at high process temperatures. In some examples, thin walls can be used that can reduce heat loss and the power consumed by the pedestal to maintain the set temperature.

[0163] A plurality of gas conduits, collectively shown as 406, are disposed through the stem portion 404 and connected to various plenums formed within the base portion 402 by different plates of the base portion 402, as described below. The conduits 406 supply gas to the plenums, as described below. Additionally, additional conduits for supplying power to a heater disposed in the base portion 402 and for sensing the temperature of the base portion 402 are also disposed through the stem portion 404, as described below. The conduits 406 are shown in detail in FIGS. 23A - 25B.

[0164] As shown in the exploded perspective view of the pedestal 400 in FIGS. 4B and 4C, the base portion 402 has four joined (e.g., brazed) plates (the first plate 410, the second plate 412, the third plate 414, and the fourth plate 416). The plates 410, 412, 414, and 416 are generally cylindrical. The stem portion 404 is coupled to the first plate 410. The heater coil 440 is disposed on the second plate 412. The various plenums described below are defined by the second, third, and fourth plates 412, 414, and 416. In some examples, a fifth plate 418 (see FIG. 5) is disposed between the second plate 412 and the third plate 414 to further define a plenum that is described in detail below. The fourth plate 416 is also referred to as the upper plate 416 of the pedestal 400, and during processing, a substrate 417 (see FIG. 5) is placed thereon. The various features of the plates 410-418 can be seen in FIGS. 4A-4C. These features will first be briefly described with reference to FIGS. 4A-4C and then described in detail with reference to FIGS. 5-12.

[0165] Referring to FIG. 4A, the upper plate 416 has various grooves. For example, the upper plate 416 has an edge gas groove 420, a purge gas groove 422, and a plurality of vacuum clamp grooves collectively shown as 424. The vacuum clamp grooves 424 will hereinafter be simply referred to as clamp grooves 424. The clamp grooves 424 include all the grooves shown inside (i.e., radially inward) the purge gas groove 422. Some of the clamp grooves 424 are concentric (i.e., annular or circular), and some of the clamp grooves 424 extend radially. The concentric clamp grooves and the radial clamp grooves are collectively referred to as clamp grooves 424, and are also individually referred to as concentric clamp grooves 424 and radial clamp grooves 424. Some of the radial clamp grooves 424 intersect the concentric clamp grooves, and some of the radial clamp grooves interconnect the concentric clamp grooves. The radial clamp grooves that intersect the concentric clamp grooves are longer than the radial clamp grooves that interconnect the concentric clamp grooves. Thus, all the radial and concentric (i.e., annular or circular) clamp grooves 424 are interconnected. Details of the clamp grooves 424 are shown in FIGS. 6A - 6C.

[0166] As can be seen from FIG. 6A, the edge gas groove 420 and the purge gas groove 422 are concentric (i.e., annular or circular). The edge gas groove 420 is located radially outermost on the upper surface of the fourth plate 416. The inner diameter (ID) of the edge gas groove 420 is larger than the diameter of the substrate 417 (represented by the dotted circle). The outer diameter (OD) of the edge gas groove 420 is smaller than the diameter of the fourth plate 416. The OD of the purge gas groove 422 is smaller than the ID of the edge gas groove 420 and also smaller than the diameter of the substrate 417.

[0167] Generally, the purge gas groove 422 is smaller in diameter than the edge gas groove 420 and the substrate 417. The purge gas groove 422 surrounds the clamp groove 424 in the radial direction. The ID diameter of the purge gas groove 422 is larger than the OD of the outermost circular clamp groove 424. Generally, the diameter of the purge gas groove 422 is larger than the diameter of the outermost circular clamp groove 424. As will be described below with reference to FIG. 5 and later, the grooves 420, 422, 424 are connected to respective separated plenums within the base portion 402 of the pedestal 400 via one or more gas channels.

[0168] In FIG. 4A, the pedestal 400 has a plurality of pockets 430-1, 430-2, and 430-3 (individually the pocket 430, collectively referred to as the pocket 430). The pockets 430 support a carrier ring (not shown) when the substrate 417 is transferred to and from the pedestal 400, as will be described below with reference to FIG. 26. The pockets 430 are formed along the outer diameter (OD) of the base portion 402 of the pedestal 400 (e.g., along the outer upper edge or outer periphery). A plurality of plates 412-416 form part of the pockets 430, as seen in FIGS. 4B and 4C. The pockets 430 are formed when the plurality of plates 412-416 are joined (e.g., brazed, welded, soldered, etc.). Therefore, the pockets 430 are uniform (i.e., integral) with the plurality of plates 412-416 and the base portion 402 of the pedestal 400. The pockets 430 are formed 120 degrees apart from each other. The pockets 430 project from the OD of the base portion 402 of the pedestal 400 and extend along the x-axis and y-axis (see FIGS. 21A and 21B). The upper ends of the pockets 430 are in the same plane or at the same height (i.e., arranged in the same plane) as the upper surface of the fourth plate 416.

[0169] Each pocket 430 has a slot 432 that extends radially to the outer edge of the base portion 402 of the pedestal 400. The edge gas groove 420 intersects the slot 432 within the pocket 430. At least one of the through holes 423 within the edge gas groove 420 is positioned within each slot 432 (see FIG. 9). As shown and described below with reference to FIGS. 22A and 22B, a carrier ring - substrate holder assembly 438 having a convex portion 436 for supporting a substrate 417 (see FIG. 5) is disposed in the slot 432 within the pocket 430.

[0170] In some examples, as described below, the pedestal 400 has an additional set of holes (see FIG. 5) that open into the pocket 430 and through which edge gas is supplied by a separate plenum within the base portion 402 of the pedestal 400. The pedestal 400 has a fifth plate (see FIG. 5) that separates some of the plenums, as described below. The above and other features of the plates 412 - 416, which can be seen in the exploded perspective views of FIGS. 4B and 4C, will be described in more detail below with reference to FIGS. 5 - 12.

[0171] FIG. 5 shows an example of a cross - sectional view of the pedestal 400. The first end of the stem portion 404 connected to the first plate 410 spreads out (i.e., extends radially outward) in the vicinity of the first plate 410. For example, the stem portion 404 has a Y - shaped configuration at the first end attached to the first plate 410. The heater coil 440 includes an inner loop positioned within a central circular region of the base portion 402 (the circumference of the circle passes through the two protrusions of the Y - shaped configuration of the stem portion 404). The wall of the stem portion 404 is also formed thick to increase creep resistance at high process temperatures. The Y - shaped configuration and large thickness of the stem portion 404 increase the heat conduction between the base portion 402 and the stem portion 404.

[0172] The heater coil 440 having a plurality of turns (e.g., more than 3 turns) is disposed within the slots on the bottom surface of the second plate 412. The heater coil 440 is disposed (e.g., sandwiched) between the bottom surface of the second plate 412 and the top surface of the first plate 410. The turns of the heater coil 440 are radially distributed from the center of the second plate 412 towards the OD of the second plate 412. In some examples, the turns of the heater coil 440 are uniformly distributed. Therefore, the turns of the heater coil 440 are uniformly distributed radially from the center of the base portion 402 of the pedestal 400 to the OD of the base portion 402 of the pedestal 400. For example, the gap between adjacent turns of the heater coil 440 may be uniform. This enables uniform heating of the radial sections or regions of the base portion 402, minimizes the temperature gradient, and improves the temperature uniformity across the radius of the base portion 402. An example of the heater coil 440 having more than 3 turns (e.g., 4 turns) is shown in FIG. 21B.

[0173] Although an example of the heater coil 440 having more than 3 turns is shown, in some examples, the pedestal 400 may have a heater coil 440 having 3 or fewer turns, and any number of turns of 4 or more can also be selected. An example of the 3-turn heater coil 440 is shown in FIG. 13. The selectability of the heater coil having additional (i.e., more than 3) turns is suggested by showing a fourth coil in dotted lines in FIG. 13. An example of the heater coil 440 having 3 turns is shown in FIG. 21A.

[0174] The second plate 412 has a circular slot on the upper surface of the second plate 412. In some examples, the fifth plate 418 is integral with the second plate 412 or the third plate 414. In some examples, the fifth plate 418 is disposed between 412 and 414 as an independent plate. For example, the fifth plate 418 can be inserted into the circular slot of the second plate 412. The bottom surface of the fifth plate 418 is brazed to the upper surface of the second plate 412 within the circular slot of the second plate 412. The upper surface of the fifth plate 418 is brazed to the bottom surface of the third plate 414. The upper surface of the fifth plate 418 is flush with the upper surface of the second plate 412 and the bottom surface of the third plate 414 (i.e., at the same height or in the same plane). The diameter of the circular slot and the fifth plate 418 is smaller than the diameter of the edge gas groove 420 and the diameter of the substrate 417. The fifth plate 418 keeps the edge gas plenum and the pocket edge gas plenum (described below) separated (i.e., separated and independent of each other), as will be described in detail below.

[0175] Throughout the present disclosure, the arrangement of the various plates and plenums within the base portion 402 is described in detail. However, these arrangements are non-limiting examples. For example, the plates and plenums may be stacked in a different configuration than described. For example, one or more of the plates of the base portion 402 may be joined / integrated. For example, the position of one or more of the plenums of the base portion 402 may be different from that shown and described.

[0176] The upper surface of the second plate 412, the bottom surface of the fifth plate 418, and the through holes 423 in the third and fourth plates 414, 416 define an edge gas plenum 442. The edge gas groove 420, the through holes 423 in the third and fourth plates 414, 416, and the edge gas plenum 442 can be collectively referred to as the edge gas plenum 442. The diameter of the pitch circle of the through holes 423 and the edge gas groove 420 are located inside the edge gas plenum 442. The through holes 423 open into the edge gas groove 420 on the upper surface of the fourth plate 416. The conduit 444 passes through the first plate 410, partially through the second plate 412, and is connected to the edge gas plenum 442. The edge gas groove 420, the through holes 423, the edge gas plenum 442, and the conduit 444 are in fluid communication with each other. The edge gas plenum 442 will be shown and described in more detail below with reference to FIG. 7. The edge gas groove 420, the through holes 423, the edge gas plenum 442, and the conduit 444 may be referred to as the first groove 420, the first set of holes, the first plenum 442, and the first conduit 444, respectively.

[0177] The upper surface of the third plate 414, the bottom surface of the fourth plate 416, and the through hole 446 define a purge gas plenum 450. The purge gas groove 422, the through hole 446, and the purge gas plenum 450 can be collectively referred to as the purge gas plenum 450. The through hole 446 opens into the purge gas groove 422 on the upper surface of the fourth plate 416. The conduit 452 passes through the first, second, and fifth plates 410, 412, 418, partially through the third plate 414, and is connected to the purge gas plenum 450. The purge gas groove 422, the through hole 446, the purge gas plenum 450, and the conduit 452 are in fluid communication with each other.

[0178] The purge gas groove 422, the through-hole 446, the purge gas plenum 450, and the conduit 452 are separated from (i.e., not in fluid communication with) the edge gas groove 420, the through-hole 423, the edge gas plenum 442, and the conduit 444. The purge gas plenum 450 will be described in more detail below with reference to FIG. 9. The purge gas groove 422, the through-hole 446, the purge gas plenum 450, and the conduit 452 may be referred to as a second groove 422, a second set of holes, a second plenum 450, and a second conduit 452, respectively.

[0179] The bottom surface of the third plate 414, the through-hole 460 in the third plate 414, and the inclined hole 462 in the fourth plate 416 define a pocket edge gas plenum 466. In some examples, the inclined hole 462 is drilled through the fourth plate 416 and extends radially outward in an upwardly inclined direction at an acute angle with respect to the z-axis through the fourth plate 416 and opens into the pocket 430. In some examples, the gas conduit connecting the plenum to the inclined hole 462 may extend vertically upward and radially outward from the plenum to connect to the inclined hole 462. In some examples, one or more of the pockets 430 of the pedestal 400 may each have one or more inclined holes 462. In some examples, not all pockets have inclined holes 462. The through-hole 460, the inclined hole 462, and the pocket edge gas plenum 466 can be collectively referred to as the pocket edge gas plenum 466. The conduit 468 passes through the first, second, and fifth plates 410, 412, 418 and is connected to the pocket edge gas plenum 466. The inclined hole 462, the through-hole 460, the pocket edge gas plenum 466, and the conduit 468 are in fluid communication with each other.

[0180] The inclined hole 462, the through hole 460, the pocket edge gas plenum 466, and the conduit 468 are separated from (i.e., not in fluid communication with) the through hole 423, the edge gas plenum 442, and the conduit 444. The inclined hole 462, the through hole 460, the pocket edge gas plenum 466, and the conduit 468 are also separated from (i.e., not in fluid communication with) the through hole 446, the purge gas plenum 450, and the conduit 452. The pocket edge gas plenum 466 will be described in more detail below with reference to FIG. 9. The pocket edge gas plenum 466, the inclined hole 462, and the conduit 468 may be referred to as a third plenum 466, a third set of holes, and a third conduit 468, respectively.

[0181] The clamp groove 424 on the upper surface of the fourth plate 416, the through hole 470 (shown in FIGS. 6A - 6C) within the fourth plate 416, and the through hole 472 of the third plate 414 define a vacuum clamp plenum. The clamp groove 424, the through hole 470, the through hole 472, and the clamp groove 424 are collectively referred to as the vacuum clamp plenum and are identified as 472 as a whole. The conduit 476 passes through the first, second, and fifth plates 410, 412, 418 and is connected to the through hole 472. The through hole 470, the through hole 472, the clamp groove 424, and the conduit 476 are in fluid communication with each other. Accordingly, the conduit 476 is connected to the vacuum clamp plenum 472. The vacuum clamp plenum 472 will be shown and described in more detail below with reference to FIGS. 6A - 6C and FIGS. 11A - 11E. The vacuum clamp plenum 472 and the conduit 476 may be referred to as a fourth plenum 472 and a fourth conduit 476, respectively.

[0182] The through-hole 470, the through-hole 472, the clamp groove 424, and the conduit 476 are separated from (i.e., not in fluid communication with) the inclined hole 462, the through-hole 460, the pocket edge gas plenum 466, and the conduit 468. The through-hole 470, the through-hole 472, the clamp groove 424, and the conduit 476 are also separated from (i.e., not in fluid communication with) the edge gas groove 420, the through-hole 423, the edge gas plenum 442, and the conduit 444. The through-hole 470, the through-hole 472, the clamp groove 424, and the conduit 476 are also separated from (i.e., not in fluid communication with) the purge gas groove 422, the through-hole 446, the purge gas plenum 450, and the conduit 452.

[0183] Further, a pair of conduits 480, 482 penetrate through the stem portion 404 of the pedestal 400 and the first plate 410 and are connected to the heater coil 440. As will be described below with reference to FIG. 26, power is supplied to the heater coil 440 through the conduits 480, 482. A conduit 484 that penetrates through the stem portion 404 of the pedestal 400 and the first and second plates 410, 412 and partially passes through the fifth plate 418 is connected to the fifth plate 418. The conduit 484 has a temperature sensor (not shown) that senses the temperature of the pedestal 400 (e.g., the temperature of the base portion 402 of the pedestal 400) at an end connected to the fifth plate 418 of the conduit 484. In some examples, the conduit 484 may pass through the fifth plate 418 and be connected to the bottom surface of the third plate 414, or may be inserted into the bottom of the third plate 414. The conduit 406 shown collectively in FIG. 1 includes the conduits 444, 452, 468, 476, 480, 482, and 484.

[0184] The supply of various gases to various plenums during substrate processing is shown and described below with reference to FIG. 26. Briefly, a first gas, also referred to as edge gas (e.g., an inert gas or a mixture of an inert gas and hydrogen gas), is supplied through a first plenum, i.e., an edge gas plenum 442. The edge gas improves the edge uniformity along the edges (e.g., the OD and bevel edges) of the substrate 417 during substrate processing.

[0185] A second gas, also called purge gas (e.g., an inert gas), is supplied through a second plenum (i.e., the purge gas plenum) 450. The second gas flows radially outward from below the substrate 417 and prevents deposition on the back surface of the substrate 417 (i.e., the side mounted on the upper surface of the fourth plate 416 of the substrate 417). The second gas also prevents the process gas from diffusing onto the upper surface of the fourth plate 416 below the substrate 417, and can prevent shape anomalies (e.g., fluorination) on the upper surface of the fourth plate 416 that may occur due to diffusion.

[0186] A third gas, also called edge gas (e.g., an inert gas or hydrogen gas), is supplied through a third plenum (i.e., the pocket edge gas plenum) 466. The third gas improves the edge uniformity along the edges of the substrate 417 (e.g., OD and bevel edges) during substrate processing. The second gas may also be heated to improve temperature uniformity and reduce cold spots in the region of the substrate 417 located directly above the pocket 430.

[0187] To process the substrate 417, the substrate is placed on a pedestal 400 in the processing chamber (see FIG. 26). Before processing the substrate 417, the substrate 417 is clamped to the upper surface of the fourth plate 416 of the pedestal 400. To clamp the substrate 417, a vacuum pump (shown in FIG. 26) evacuates gas from the processing chamber by removing gas from the processing chamber through a fourth plenum (i.e., the above-mentioned clamp plenum 472).

[0188] Since the first, second, third, and fourth plenums 442, 450, 466, and 472 are separated as described above, the gases flowing through the first, second, third, and fourth plenums 442, 450, 466, and 472 do not mix with each other. The first gas flowing through the first plenum 442 does not mix with the gases flowing through the second, third, and fourth plenums 450, 466, and 472, respectively. The second gas flowing through the second plenum 450 does not mix with the gases flowing through the first, third, and fourth plenums 442, 466, and 472, respectively. The third gas flowing through the third plenum 466 does not mix with the gases flowing through the first, second, and fourth plenums 442, 450, and 472, respectively. The gas flowing through the fourth plenum 472 also does not mix with the gases flowing through the first, second, and third plenums 442, 450, and 466, respectively.

[0189] Figures 6A - 6C show top views of the pedestal 400. All the grooves in Figures 6A - 9 are shown as a single line for illustration purposes. Each of the circular grooves (e.g., the edge gas groove 420, the purge gas groove 422, and the concentric clamp groove 424) has a circular groove provided between two concentric circles that define the inner diameter (ID) and the outer diameter (OD) of the circular groove (see, for example, Figure 12). Each of the linear grooves (e.g., the radial clamp grooves 424 and the linear or spoke-like grooves shown in Figures 7 - 9) has a groove disposed between two parallel lines that extend together (see, for example, Figure 11A). In the description of Figures 6A - 25B, for the sake of brevity, elements denoted with the same reference numerals as those already described with reference to Figures 4 and 5 and which have already been explained with reference to Figures 4 and 5 will not be explained again.

[0190] FIG. 6A shows a top view (i.e., the upper surface) of the fourth plate 416 of the pedestal 400. Specifically, the arrangement of the grooves 420, 422, 424 on the upper surface of the fourth plate 416 is shown. Since the diameters of the grooves 420, 422, 424 have already been described above with reference to FIG. 4A, for the sake of brevity, no further description will be given. The details of the clamp groove 424 in the vicinity of the central region 419 of the upper surface of the fourth plate 416, which is identified by the dotted rectangle, are shown in FIGS. 11A to 11C. The through holes 470 in the clamp groove 424 in the vicinity of the central region of the upper surface of the fourth plate 416 are shown in FIGS. 6B, 6C and 11A.

[0191] In FIG. 6A, in order to reduce the cold spot of the substrate 417 caused by the pocket 430, the radially inner end of the slot 432 is recessed radially outward. The purge gas groove 422 and the outermost circular clamp groove 424 have rounded portions 434-1, 434-2 that are provided facing the radially inner end of the slot 432 and are rounded inward in the radial direction. The ID of the edge gas groove 420 is increased in order to reduce the overhang of the substrate 417 onto the slot 432 in the pocket 430, thereby improving the non-uniformity at the substrate edge. The edge gas groove 420 intersects the radially inner end of the slot 432. At least one of the through holes 423 in the edge gas groove 420 is provided at the radially inner end of the slot 432 (more clearly shown in FIG. 9).

[0192] FIG. 6B shows a bottom view (i.e., the bottom surface) of the fourth plate 416. On the bottom surface of the fourth plate 416, the through holes 446 of the purge gas plenum (shown as 450 in FIG. 5) and the inclined holes 462 of the pocket edge gas plenum (shown as 466 in FIG. 5) can be seen. The through holes 470 of the vacuum clamp plenum 472 can also be seen on the bottom surface of the fourth plate 416. The through holes 470 are shown in more detail in FIG. 6C.

[0193] Instead of a pair of through-holes formed in the notch on the upper surface of the fourth plate 416 (see FIG. 14B) that may cause cold spots on the substrate 417 in the region located above the notch, as shown in FIG. 6C, the fourth plate 416 has at least two pairs of through-holes 470. The through-holes 470 are directly disposed not in the notch but in the clamp groove 424. By eliminating the notch, the corresponding cold spots are eliminated. The arrangement of the through-holes 470 in the corresponding clamp groove 424 and other features such as the width, depth, and roundness of the clamp groove 424 will be shown and described in more detail below with reference to FIGS. 11A - 11C.

[0194] FIG. 7 shows a top view (i.e., the upper surface) of the second plate 412 of the pedestal 400. The second plate 412 has five through-holes 490, 492, 494, 496, 498 through which each of the five conduits 444, 452, 468, 476, 484 (see FIG. 5) passes. The edge gas plenum (shown as 442 in FIG. 5) is formed by an annular groove 421 and a plurality of radial grooves 425 on the upper surface of the second plate 412. The ID of the annular groove 421 is equal to the diameter of the fifth plate 418. The fifth plate 418 is placed on the ID of the annular groove 421 and covers the radial grooves 425. The radial grooves 425 connect the through-holes 490 to the annular groove 421. The edge gas flows from the conduit 444, through the through-hole 490, through the radial groove 425, through the annular groove 421, and through the through-hole 423 (see FIG. 5) to the edge gas groove 420 on the upper surface of the fourth plate 416.

[0195] FIG. 8 shows a bottom view (i.e., the bottom surface) of the third plate 414. The bottom surface of the third plate 414 has three holes 492, 494, 496 through which the three conduits 452, 468, 476 (see FIG. 5) respectively pass. The pocket edge gas plenum (shown as 466 in FIG. 5) is formed by a plurality of radial grooves 427 and a through-hole 460 that connects to the inclined hole 462 (see FIG. 5) of the fourth plate 416. The radial grooves 427 connect the hole 494 to the through-hole 460.

[0196] The diameter of the fifth plate 418 is larger than the diameter of the pitch circle of the through holes 460 (i.e., the circle on which the plurality of through holes 460 are located) and smaller than the ID of the edge gas groove 420 (see FIG. 5) in which the through hole 423 is located. Therefore, the upper surface of the fifth plate 418 completely or entirely covers the pocket edge gas plenum 466. Thus, as shown and described above with reference to FIG. 7, the fifth plate 418 separates the pocket edge gas plenum 466 from the edge gas plenum 442 formed in the second plate 412. Edge gas flows from the conduit 468, through the hole 494, through the radial groove 427, through the through hole 460, and through the inclined hole 462 (see FIG. 5) into the pocket 430.

[0197] FIG. 9 shows a top view (i.e., the upper surface) of the third plate 414. The upper surface of the third plate 414 has holes 492, 496 through which conduits 452, 476 respectively pass. The purge gas plenum (shown as 450 in FIG. 5) is formed by a first plurality of radial grooves 433, an annular groove 431, and a second plurality of radial grooves 429. The second plurality of radial grooves 429 has more grooves than the first plurality of radial grooves 433. The first plurality of radial grooves 433 connect the hole 492 to the annular groove 431. The first ends of the second plurality of radial grooves 429 are connected to the annular groove 431. The second ends of the second plurality of radial grooves 429 are connected to the through holes 446 (see FIG. 5) of the fourth plate 416. Purge gas flows from the conduit 444, through the hole 492, through the first plurality of radial grooves 433, through the annular groove 431, through the second plurality of radial grooves 429, and through the through holes 446 (shown in FIG. 5) to the purge gas groove 422 on the upper surface of the fourth plate 416.

[0198] FIG. 10 shows a top view and a bottom view (which are the same) of the fifth plate 418. The fifth plate 418 has four through-holes 492, 494, 496, 498 through which four conduits 452, 468, 476, 484 (see FIG. 5) respectively pass. In some examples, a temperature sensor may be embedded in the fifth plate 418. In that case, element 498 may not be a hole partially dug into the bottom surface of the fifth plate 418, and the conduit 484 may end in the hole 498 partially dug into the fifth plate 418.

[0199] The first plate 410 has seven through-holes (see FIG. 5). The conduits 444, 452, 468, 476, 480, 482, 484 pass through the first plate 410 through the through-holes and pass through the other plates as described above. The conduit 476 passes through the first plate 410 and through the through-holes 496 of the second and fifth plates 412, 418 and is connected to the through-hole 472 of the third plate 414. The through-hole 472 is connected to the clamp groove 424 through the through-hole 470 of the fourth plate 416. A vacuum pump (shown in FIG. 26) discharges the gas in the processing chamber by removing the gas from the processing chamber through the clamp groove 424, the through-hole 470, the through-hole 472, and the conduit 476.

[0200] FIGS. 11A-11D show the clamp groove 424 and the through-hole 470 in the clamp groove in more detail. As described above with reference to FIGS. 6A-6C and as shown in FIG. 11A, the through-hole 470 is not located in the notch formed at the intersection of the radial clamp grooves 424 near the central region of the upper surface of the fourth plate 416. An example of the case of being located in the notch is shown in FIG. 14B. Instead, as shown in FIGS. 6C and 11A, the through-hole 490 is disposed in the radial clamp groove 424 at the intersection of the radial clamp grooves 424 near the central region of the upper surface of the fourth plate 416.

[0201] Furthermore, as shown in FIGS. 6C and 11A, the through-holes 470 are arranged in multiple rows within the radial clamp grooves 424 (for example, two rows are shown, but additional rows can be added). Each row of the through-holes 470 is located on a circle. Thus, the rows of the through-holes 470 are located on respective concentric circles. Since the conduit 476 is connected to the through-holes 470 via the through-holes 472 in the third plate 414 positioned below the through-holes 470 (see FIG. 5), the through-holes 490 are located at the intersections of the radial clamp grooves 424 near the central region of the upper surface of the fourth plate 416. The through-holes 470 are not positioned in any of the clamp grooves 424 other than those shown in FIG. 11A.

[0202] FIG. 11B shows that the width w of the clamp grooves 424 (either the radial and circular clamp grooves 424 shown in FIG. 6A) is smaller than the depth d of the clamp grooves 424 (either the radial and circular clamp grooves 424 shown in FIG. 6A). When the width of the clamp grooves 424 becomes narrower, the cold spots of the substrate 417 that can be caused by the clamp grooves 424 decrease. Due to the depth of the clamp grooves 424, it becomes possible to arrange multiple rows of through-holes 470 within the clamp grooves 424. The through-holes 470 arranged within the clamp grooves 424 as shown in FIGS. 6C and 11A have a smaller diameter but a larger number than the through-holes 470 arranged within the circular notch shown in FIG. 14B. Thus, the clamping force provided by the through-holes 470 arranged within the clamp grooves 424 as shown in FIGS. 6C and 11A is not decreased compared to the clamping force provided by the through-holes 470 arranged within the circular notch shown in FIG. 14B. Rather, by adding more rows of through-holes 470, it is possible to increase the clamping force. Furthermore, by eliminating the notches for arranging the through-holes 470 and reducing the width of the clamp grooves, the cold spots of the substrate 417 are minimized.

[0203] FIG. 11C shows that the outer edges of the clamp grooves 424 (either the radial and circular clamp grooves 424 shown in FIG. 6A) are also rounded as indicated at 477. Rounding the clamp grooves 424 provides additional advantages. As shown in FIG. 11D, when process gas diffuses under the substrate 417, substances formed by chemical reactions between the diffused process gas, for example having a corrosive halogen, and the metal material on the upper surface of the fourth plate 416 accumulate over time to form deposits (shown as 478). If the clamp grooves 424 are not rounded as in FIG. 11C, the deposits grow above the plane of the upper surface of the fourth plate 416 as shown at 478. Due to the growth of the deposits, a gap (shown as 481) exists between the bottom surface of the substrate 417 and the upper surface of the fourth plate 416. This gap allows more process gas to diffuse under the substrate 417, thereby causing more substances to deposit and accumulate, further increasing the gap between the bottom surface of the substrate 417 and the upper surface of the fourth plate 416. As a result, the substrate 417 is not properly clamped to the upper surface of the fourth plate 416, resulting in process non-uniformity and temperature non-uniformity of the substrate 417.

[0204] Instead, when the clamp grooves 424 are rounded as in FIG. 11C, when process gas diffuses under the substrate 417, the deposits grow below the plane of the upper surface of the fourth plate 416 as indicated at 483 in FIG. 11E. Due to the growth of the deposits below the plane of the upper surface of the fourth plate 416, a gap (shown as 485 in FIG. 11E) exists between the deposits and the upper surface of the fourth plate 416. The gap between the deposits and the upper surface of the fourth plate 416 allows the bottom surface of the substrate 417 to contact the upper surface of the fourth plate 416, and the substrate 417 is properly clamped to the upper surface of the fourth plate 416, thereby improving the process uniformity and temperature uniformity of the substrate 417.

[0205] In some examples, the radius of the rounded edge of the clamp groove 424, shown as 477, can be up to 0.04 inches (1.016 mm) maximum. Further, this larger radius also helps to prevent process variations due to surface irregularities caused by excessive fluorination (corrosion) on the upper surface of the fourth plate 416 of the pedestal 400.

[0206] FIG. 12 shows the distance between the edge gas groove 420, the purge gas groove 422, and the radially inner end of the pocket 430 and the radially inner end of the protrusion 436 of the carrier ring - substrate holder assembly 438 disposed within the slot 432 of the pocket 430. Specifically, as described above, the ID of the edge gas groove 420 is made large to minimize the overhang of the substrate. Further, as described above, the slot 432 of the pocket 430 and the protrusion 436 of the carrier ring - substrate holder assembly 438 are recessed radially outward to minimize cold spots that may be caused by the pocket 430. Specifically, the inner end of the pocket 430 and the inner end of the protrusion 436 of the carrier ring - substrate holder assembly 438 are closer to the ID of the edge gas groove 420 than to the OD of the purge gas groove 422.

[0207] For example, the radial distance between the radially inner edge of the slot 432 and the ID of the edge gas groove 420 is d1. The radial distance between the radially inner edge of the protrusion 436 and the ID of the edge gas groove 420 is d2. The radial distance between the radially inner edge of the slot 432 and the OD of the purge gas groove 422 is d3. The radial distance between the radially inner edge of the protrusion 436 and the OD of the purge gas groove 422 is d4, and d1 < d3 and d2 < d4. Thus, the inner end of the pocket 430 and the inner end of the protrusion 436 of the carrier ring - substrate holder assembly 438 are closer to the ID of the edge gas groove 420 than to the OD of the purge gas groove 422.

[0208] Figures 13, 14A, and 14B show another example of the pedestal 500. Figure 13 shows a cross-sectional view of the pedestal 500. The pedestal 500 is identical to the pedestal 400 shown in FIGS. 4 to 12, except for the following differences. Therefore, except for the following differences, the other elements of the pedestal 500 will not be described again for the sake of brevity.

[0209] The main difference between the pedestal 500 and the pedestal 400 is that, unlike the pedestal 400 in which the edge gas plenum 442 and the pocket edge gas plenum 466 are separated, in the pedestal 500, the edge gas plenum 442 and the pocket edge gas plenum 466 are not separated. Instead, in the pedestal 500, the edge gas plenum 442 and the pocket edge gas plenum 466 are in fluid communication with each other and form a single, integrated, or shared plenum. Therefore, the pedestal 500 does not have the fifth plate 418 that separates the edge gas plenum 442 and the pocket edge gas plenum 466 in the pedestal 400 as shown in FIG. 5. Thus, in the pedestal 500, the bottom surface of the third plate 414 does not have the pocket edge gas plenum 466 and is flat. The pedestal 500 also does not have the conduit 468 that is used to supply edge gas to the pocket edge gas plenum 466 independently in the pedestal 400 as shown in FIG. 5. Instead, in the pedestal 500, the conduit 444 supplies edge gas to both the edge gas groove 420 (through the through-hole 423) and the pocket 430 (through the inclined hole 462).

[0210] Furthermore, in the pedestal 500, in some examples, the heater coil 440 may have three or more turns as shown in FIG. 5. In the example shown in FIG. 13, a heater coil 440 with additional (i.e., more than three) turns can also be selected, as suggested by showing a fourth coil with a dotted line. Thus, as shown in FIG. 13, the pedestal 500 has a heater coil 440 with three turns, an example of which is shown as 440-1 in FIG. 21A. In some examples, the pedestal 500 may have a heater coil with four turns, an example of which is shown as 440-2 in FIG. 21B. The heater coils 440-1 and 440-2 are collectively and generally referred to as the heater coil 400.

[0211] FIG. 14A is a top view of the fourth plate 416 of the pedestal 500. The top view of the fourth plate 416 of the pedestal 500 is the same as the top view of the fourth plate 416 of the pedestal 400 except for the following differences. Unlike the fourth plate 416 of the pedestal 400, the fourth plate 416 of the pedestal 500 further has ceramic springs (collectively referred to as the springs 502) shown as 502-1, 502-2, and 503-2. As shown in the drawing, the ceramic springs 502 are arranged along the circumference of the middle circular clamp groove 424. Similar to the pockets 430, the ceramic springs are arranged 120 degrees apart from each other. In some examples, the ceramic springs 502 are arranged radially aligned with the pockets 430 as shown in the drawing, but they can also be arranged differently from that shown. Since the ceramic springs 502 may cause cold spots on the substrate 417, in some examples, the ceramic springs 502 can be omitted in the pedestal 500.

[0212] FIG. 14B shows another characteristic of the pedestal 500, which is different from the pedestal 400. Different from the pedestal 400 where the fourth plate 416 shown in FIGS. 6C and 11A does not have a circular notch for the through-hole 470, the fourth plate 416 of the pedestal 500 has circular notches shown as 504-1 and 504-2 (collectively referred to as the circular notch 504). An enlarged view of the central portion 499 of the fourth plate 416 is shown in FIG. 14B. A set of through-holes 470 is arranged along the circumference of the notch 504-1 within the notch 504-1. Alternatively, the through-holes 470 may be arranged within the circumference of the notch 504-1. Since the circular notch 504 may cause cold spots on the substrate 417, in some examples, the circular notch 504 can be omitted in the pedestal 500.

[0213] In some examples, the pedestal 500 may have any combination of the following features together with either a shared plenum (without the fifth plate 418) that supplies edge gas to the edge gas groove 420 through the through-hole 423 and to the pocket 430 through the inclined hole 462, or a separated plenum (with the fifth plate 418) that supplies edge gas to the edge gas groove 420 through the through-hole 423 and to the pocket 430 through the inclined hole 462, that is, the heater coil 440 shown in FIG. 21A or FIG. 21B, with or without the ceramic spring 502, a set of through-holes 470 within the circular notch 504 shown in FIG. 14B or multiple sets of through-holes 470 without the circular notch 504 shown in FIGS. 6C and 11A, and the unrounded or rounded clamp groove 424 shown in FIGS. 11A-11E.

[0214] Figures 15 to 17 show additional examples of pedestals 600 and 700. Figures 15 and 16 show cross-sectional views of pedestals 600 and 700 respectively. The top views of the fourth plates 416 of both pedestals 600 and 700 are shown in Figure 17. Pedestals 600 and 700 may have the same or similar features as the pedestal 400 shown and described with reference to Figures 4 to 12, except for the differences described below. Therefore, except for the following differences, the other elements of pedestals 600 and 700 will not be described again for the sake of brevity.

[0215] In Figure 15, the main difference between pedestal 600 and pedestal 400 is that, unlike pedestal 400, purge gas is not supplied through the purge gas groove 422 in pedestal 600. Instead, a purge gas plenum 450 is used to supply edge gas to the pocket 430. This operation is carried out in pedestal 400 using the pocket edge gas plenum 466 as shown in Figure 5. Therefore, pedestal 600 does not have the corresponding elements 422, 446, 429, and 452 of pedestal 400 described and shown with reference to Figure 5. The pocket edge gas plenum 466 shown in Figure 15 is the same as the purge gas plenum 450 shown in Figure 5, which does not have the elements 422, 446, 429, and 452 of pedestal 400 shown in Figure 5, and is further modified as follows to function as the pocket edge gas plenum 466.

[0216] Specifically, in pedestal 600, the pocket edge gas plenum 466 (i.e., the purge gas plenum 450 shown in FIG. 5 without the elements 422, 446, 429, and 452 of pedestal 400 shown in FIG. 5) is modified as follows to function as the pocket edge gas plenum 466 of pedestal 400 in FIG. 5. In pedestal 600, conduit 468 extends through the first and second plates 410, 412 as in the case of pedestal 400 shown in FIG. 5, and further extends partially through the third plate 414 as shown in FIG. 15. Conduit 468 is connected to what is the purge gas plenum 450 in pedestal 400 shown in FIG. 5 (the pocket edge gas plenum 466 in pedestal 600). Therefore, in pedestal 600, the pocket edge gas plenum 466 and the through hole 460 as shown in FIG. 5 are eliminated, and instead, as shown in FIG. 15, the purge gas plenum 450 shown in FIG. 5, which is the pocket edge gas plenum 466 in FIG. 15, is connected to the inclined hole 462 to supply edge gas to the pocket 430 of pedestal 600. Since the pocket edge gas plenum 466 and the through hole 460 as shown in FIG. 5 are eliminated in FIG. 15, pedestal 600 in FIG. 15 also does not have the fifth plate 418, and the bottom surface of the third plate 414 is flat.

[0217] Therefore, pedestal 600 does not have the pocket edge gas plenum 466 of pedestal 400 shown in FIG. 5. Instead, the purge gas plenum 450 shown in FIG. 5 is modified as described above and is used as the pocket edge gas plenum 466 within pedestal 600 as shown and described in FIG. 15. Thus, the pocket edge gas plenum 466 of pedestal 600 is also referred to as the pocket edge gas plenum 466 / 450 or the pocket edge gas plenum 466’ / 450’. Here, the “’” represents the modifications added to the plenums 450 and 466 within the pedestal with respect to pedestal 400 as shown and described in FIG. 15.

[0218] Furthermore, in the pedestal 600, in some examples, the heater coil 440 may have three or more turns as shown in FIG. 5. In the example shown in FIG. 15, a heater coil 440 with additional (i.e., more than three) turns can also be selected, as suggested by showing a fourth coil with a dotted line. Thus, as shown in FIG. 15, the pedestal 600 may have a three-turn heater coil 440, an example of which is shown in FIG. 21A. In some examples, the pedestal 600 may have a heater coil 440 with four turns, an example of which is shown in FIG. 21B.

[0219] In FIG. 16, the main difference between the pedestal 700 and the pedestal 400 is that, unlike the pedestal 400 where the edge gas plenum 442 and the pocket edge gas plenum 466 are separated, in the pedestal 700, the edge gas plenum 442 and the pocket edge gas plenum 466 are in fluid communication with each other and form a single, integrated, or shared edge gas plenum 442. Therefore, the pedestal 700 does not have the fifth plate 418 that separates the edge gas plenum 442 and the pocket edge gas plenum 466 as shown in FIG. 5 in the pedestal 400. Thus, in the pedestal 700, the bottom surface of the third plate 414 does not have the pocket edge gas plenum 466 and is flat. The pedestal 700 also does not have the conduit 468 that is used in the pedestal 400 to independently supply edge gas to the pocket edge gas plenum 466 as shown in FIG. 5. Instead, in the pedestal 700, the conduit 444 supplies both the edge gas groove 420 (through the through hole 423) and the pocket 430 (through the inclined hole 462).

[0220] Furthermore, the main difference between pedestal 700 and pedestal 400 is that, unlike pedestal 400, pedestal 700 does not have a purge gas plenum 450 for supplying purge gas through purge gas groove 422. Therefore, pedestal 700 also does not have the elements 422, 446, 429, 433, 450, and 452 of pedestal 400 shown in FIG. 5. Further, in pedestal 700, since the upper surface of the third plate 414 does not have a purge gas plenum 450, the upper surface of the third plate 414 is also flat.

[0221] Furthermore, in pedestal 700, in some examples, the heater coil 440 may have three or more turns as shown in FIG. 5. In the example shown in FIG. 16, a heater coil 440 with additional (i.e., more than three) turns can also be selected, as suggested by showing a fourth coil with a dotted line. Thus, as shown in FIG. 16, pedestal 700 may have a three-turn heater coil 440, an example of which is shown in FIG. 21A. In some examples, pedestal 700 may have a four-turn heater coil 440, an example of which is shown in FIG. 21B.

[0222] FIG. 17 shows a top view of the upper surface of the fourth plate 416 for pedestals 600 and 700 shown in FIGS. 15 and 16, respectively. The top view of the upper surface of the fourth plate 416 for pedestals 600 and 700 is the same as the top view of the fourth plate 416 of pedestal 400 shown in FIGS. 6A - 6C, except for the following differences. The fourth plates 416 of pedestals 600 and 700 do not have a purge gas groove 422 and a corresponding through hole 446. Further, the edge gas groove 420 and the outermost circular clamp groove 424 do not have rounded portions 434 - 1, 434 - 2 provided opposite the radially inner end of the slot 432.

[0223] The through holes 470 of the fourth plate 416 for pedestals 600 and 700 are as shown in FIGS. 11A - 11C. However, in some examples, the through holes 470 may be arranged as shown in FIG. 14B in the fourth plate 416 for pedestals 600 and 700. Further, in some examples, pedestals 600 and 700 may have no purge gas plenum 450 and either a shared plenum (no fifth plate 418) that supplies edge gas to the edge gas groove 420 through the through hole 423 and to the pocket 430 through the inclined hole 462, or a separated plenum (since the purge gas plenum 450 is used as the pocket edge gas plenum 466, there is still no fifth plate 418) that supplies edge gas to the edge gas groove 420 through the through hole 423 and to the pocket 430 through the inclined hole 462, along with any combination of the following features: namely, the heater coil 440 shown in FIG. 21A or FIG. 21B, with or without the ceramic spring 502, and either a set of through holes 470 within the circular notch 504 shown in FIG. 14B or multiple sets of through holes 470 without the circular notch 504 shown in FIGS. 6C and 11A, and the unrounded or rounded clamp groove 424 shown in FIGS. 11A - 11E.

[0224] FIG. 18 shows another example of pedestal 800. Pedestal 800 may have the same or similar features as pedestal 400 shown and described with reference to FIGS. 4 - 12, except for the differences described below. Therefore, except for the following differences, the other elements of pedestal 800 will not be described again for the sake of brevity.

[0225] The main difference between pedestal 800 and pedestal 400 is that, unlike pedestal 400, pedestal 800 does not have a pocket edge gas plenum 466. Therefore, in pedestal 800, the bottom surface of the third plate 414 is flat without a pocket edge gas plenum 466. Further, pedestal 800 also does not have the elements 466, 460, 462, and 468 of pedestal 400 shown in FIG. 5. Additionally, pedestal 800 does not have a fifth plate 418 that separates the edge gas plenum 442 and the pocket edge gas plenum 466 in pedestal 400 as shown in FIG. 5.

[0226] Furthermore, in pedestal 800, in some examples, the heater coil 440 can also have more than three turns as shown in FIG. 5. In the example shown in FIG. 18, a heater coil 440 with additional (i.e., more than three) turns can also be selected, as suggested by showing a fourth coil with a dotted line. Thus, as shown in FIG. 18, pedestal 800 has a three-turn heater coil 440, an example of which is shown as 440-1 in FIG. 21A. In some examples, pedestal 800 can also have a four-turn heater coil, an example of which is shown as 440-2 in FIG. 21B.

[0227] The top view of the fourth plate 416 of pedestal 800 is the same as the top view of the fourth plate 416 of pedestal 400 shown in FIG. 6A, except for the following differences. In some examples, pedestal 800 can have any combination of the following features: the heater coil 440 shown in FIG. 21A or FIG. 21B, with or without a ceramic spring 502, one set of through holes 470 within the circular notch 504 shown in FIG. 14B or multiple sets of through holes 470 without the circular notch 504 shown in FIG. 6C and FIG. 11A, and the unrounded or rounded clamp grooves 424 shown in FIGS. 11A - 11E.

[0228] FIG. 19 shows yet another example of pedestal 900. Pedestal 900 may have the same or similar features as pedestal 400 shown and described with reference to FIGS. 4 - 12, except for the differences described below. Therefore, except for the following differences, the other elements of pedestal 900 will not be described again for the sake of brevity.

[0229] The main difference between pedestal 900 and pedestal 400 is that, unlike pedestal 400, pedestal 900 does not have a pocket edge gas plenum 466 and a purge gas plenum 450. Therefore, pedestal 900 does not have a third plate 414 and a fifth plate 418. Further, pedestal 900 also does not have elements 466, 460, 462, and 468 of pedestal 400 shown in FIG. 5. Additionally, pedestal 800 also does not have elements 450, 429, 433, 446, 422, and 452 of pedestal 400 described and shown with reference to FIG. 5.

[0230] Furthermore, in pedestal 900, in some examples, the heater coil 440 may have more than 3 turns as shown in FIG. 5. In the example shown in FIG. 19, a heater coil 440 with additional (i.e., more than 3) turns can also be selected, as suggested by showing a fourth coil with a dotted line. Thus, as shown in FIG. 19, pedestal 900 may have a 3 - turn heater coil 440, an example of which is shown in FIG. 21A. In some examples, pedestal 900 may have a 4 - turn heater coil 440, an example of which is shown in FIG. 21B.

[0231] The top view of the fourth plate 416 of the pedestal 900 is identical to the top view of the fourth plate 416 of the pedestals 600 and 700 shown in FIG. 17, except for the following differences. In some examples, the pedestal 900 may have any combination of the following features: a heater coil 440 shown in FIG. 21A or FIG. 21B, with or without a ceramic spring 502; a set of through holes 470 within the circular notch 504 shown in FIG. 14B or multiple sets of through holes 470 without the circular notch 504 shown in FIG. 6C and FIG. 11A; and unrounded or rounded clamp grooves 424 shown in FIGS. 11A - 11E.

[0232] FIGS. 20A and 20B are side front views of the pocket 430. FIG. 20A shows the pocket 430 of the pedestals 400, 500, 600, 700, and 800. FIG. 20B shows the pocket 430 of the pedestal 900. In FIGS. 20A and 20B, the position where the plate is brazed is shown as the brazing interface 1000.

[0233] As described above, each pocket 430 has a slot 1002 in which a nut plate and a washer (see FIG. 22A) are disposed. A fastener (shown in FIG. 22A) is inserted into a hole 1004 of a wheel block assembly (shown in FIG. 22A) disposed within the pocket 430 and engages with the nut plate within the slot 1002 of the pocket 430 to fix the wheel block assembly to the pedestal.

[0234] As shown in FIGS. 20A and 20B, within each pocket 430, slot 1002 is formed in the radially outer wall of pocket 430. Slot 1002 is positioned away from the brazing interfaces 1000 of the plurality of plates 412 - 416 such that slot 1002 is not positioned at any of the brazing interfaces 1000. None of the brazing interfaces 1000 intersects slot 1002. Slot 1002 does not include any of the brazing interfaces 1000. Instead, slot 1002 is positioned between the brazing interfaces 1000 of adjacent plates. Slot 1002 is entirely formed within the thickness of any one of plates 412 - 416. The height of slot 1002 is less than the thickness of any one of plates 412 - 416 in which slot 1002 is formed. Thus, a larger area of the plate can be used for brazing the plate, resulting in an increase in the joining force between the plates. Further, even when the washer expands, since the mechanical force due to expansion is smaller than the joining force that keeps the plates in a joined state, peeling of pocket 430 can be prevented.

[0235] FIGS. 21A and 21B show an example of heater coil 440. FIG. 21A shows an example of heater coil 440 with three turns, indicated as 440 - 1. FIG. 21B shows an example of heater coil 440 with four turns, indicated as 440 - 4. Throughout the present disclosure, heater coils 440 - 1 and 440 - 2 are collectively and generally referred to as heater coil 440. In some examples, heater coil 440 may have additional turns. The heater coil has first and second ends 1110, 1112 to which conduits 480, 482 are respectively connected. As will be described below with reference to FIG. 26, power is supplied to heater coil 440 through conduits 480, 482. Based on the number of turns of heater coil 440, the bottom surface of the second plate 412 has a groove (not shown) in which heater coil 440 is disposed.

[0236] Figures 22A and 22B show examples of the wheel block assembly 1050 and the carrier ring - substrate holder assembly 438. In Figure 22A, the wheel block assembly 1050 is disposed in the slot 432 within the pocket 430. The wheel block assembly 1050 has wheels 1054 - 1, 1054 - 2. A plurality (e.g., three) of carrier ring - substrate holder assemblies 438 are attached to the bottom surface of the carrier ring 1051. When the carrier ring 1051 (see, e.g., Figure 5) carrying the substrate 417 is loaded onto the pedestal, the carrier ring - substrate holder assembly 438 is inserted into the wheel block assembly 1050. The wheels 1054 - 1, 1054 - 2 grip the carrier ring - substrate holder assembly 438 within the wheel block assembly 1050.

[0237] In Figure 22B, the carrier ring - substrate holder assembly 438 has a substrate holder (also called a contact finger) 437 that extends radially inward from the pocket 430. The contact finger 437 has a protrusion 436 for supporting the substrate 417 and a centering wheel 439 for centering the substrate 417 on the pedestal. The wheel block assembly 1050 is fixed to a nut plate 1058 within the pocket 430 using a fastener 1056 that passes through a hole 1004 in the wheel block assembly 1050. A washer 1060 is used with the fastener 1056 and the nut plate 1058. The nut plate 1058 is inserted into a slot 1002 located at the base of the pocket 430. Since the position of the slot 1002 and the advantages provided by the position of the slot 1002 have already been described above with reference to Figures 20A and 20B, they will not be repeated here for the sake of brevity.

[0238] Figures 23A to 25B show examples of the arrangement of conduits 406 within the stem portion 404 of a part of the pedestal described above. Figures 23A and 23B show the arrangement of conduits 444, 452, 468, 476, 480, 482, 484 of the pedestal 400. Figure 23A shows a cross-sectional view of the stem portion 404 of the pedestal 400, together with the conduits within the stem portion 404 of the pedestal 400. Figure 23B shows a perspective view of the stem portion 404 of the pedestal 400.

[0239] In Figures 23A and 23B, the conduits 444, 452, 468, 476, 484 are arranged through a narrow opening 1102 at the lower end of the stem portion 404 of the pedestal 400 as shown. As will be described below, the heater conduits 480, 482 do not extend through the opening 1102. Instead, only the conductors 480-1, 482-1 of the heater coils 440 within the heater conduits 480, 482 extend through the opening 1102. The opening 1102 of the stem portion 404 of the pedestal 400 is the same as the opening 1102 of the stem portion 404 of the pedestal 500 that uses a smaller number of conduits than the pedestal 400 as shown in Figures 24A and 24B. Therefore, a larger number of conduits are arranged in the opening 1102 of the stem portion 404 of the pedestal 400 than the number of conduits arranged through the same opening 1102 of the stem portion 404 of the pedestal 500.

[0240] In some examples, in order to accommodate a greater number of conduits within the opening 1102 of the stem portion 404 of the pedestal 400 without increasing the size of the opening 1102, the conduits 480, 482 are shorter than other conduits and do not extend out of the lower end of the stem portion 404 through the opening 1102. Instead of the conduits 480, 482, only the conductors 480-1, 482-1 (see FIGS. 23A and 23B) of the heater coil 440 that supply power to the heater coil 440 within the conduits 480, 482 extend out of the lower end of the stem portion 404 through the opening 1102 and are connected to a power source. Outside of the conduits 480, 482, the conductors 480-1, 482-1 are electrically insulated using an insulating material so as not to cause a short circuit with the stem portion 404 or other components of the substrate processing system. The insulating material is capable of withstanding high thermal and mechanical stresses and is also resistant to strong process chemicals. The stem portion 404 has an opening 1100 for a fastener (not shown) that attaches the stem portion 404 to other components of the substrate processing system.

[0241] FIGS. 24A and 24B show the arrangement of the conduits 444, 452, 476, 480, 482, 484 of the pedestal 500. FIG. 24A shows a cross-sectional view of the stem portion 404 of the pedestal 500, along with the conduits within the stem portion 404 of the pedestal 500. FIG. 24B shows a perspective view of the stem portion 404 of the pedestal 500. The conduits 444, 452, 480, 482, 484, 476 are arranged through a narrow opening (e.g., notch) 1102 at the upper end of the stem portion 404 of the pedestal 500 as shown. The conductors 480-1, 482-1 of the heater coil 440 that supply power to the heater coil 440 are shown. The stem portion 404 has an opening 1100 for a fastener (not shown) that attaches the stem portion 404 to other components of the substrate processing system.

[0242] Figures 25A and 25B show the arrangement of conduits 444, 476, 480, 482, 484 of pedestal 900. Figure 25A shows a cross-sectional view of stem portion 404 of pedestal 900, along with the conduits within stem portion 404 of pedestal 900. Figure 25B shows a perspective view of stem portion 404 of pedestal 500. Conduits 444, 480, 482, 484, 476 are arranged through a narrow opening (e.g., notch) 1102 at the upper end of stem portion 404 of pedestal 900, as shown. Stem portion 404 has an opening 1100 for a fastener (not shown) that attaches stem portion 404 to other components of the substrate processing system.

[0243] Figure 26 shows an example of a substrate processing system 1200 in which any of the above pedestals can be used. Substrate processing system 1200 has a station (also called a process module) 1212 where a substrate is processed. Only one station 1212 is shown as an example, but substrate processing system 1200 may have multiple stations 1212. Each station 1212 may use any of the above pedestals. For example, the substrate may be processed sequentially at multiple stations 1212. Different processes such as atomic layer deposition (ALD), chemical vapor deposition (CVD), plasma-enhanced ALD (PEALD), plasma-enhanced CVD (PECVD), etc. may be performed on substrates at different stations using the different above pedestals.

[0244] Station 1212 has a pedestal 1214 and a showerhead 1216. Pedestal 1214 may be any of the above pedestals. Pedestal 1214 may have a base portion 1218 (e.g., the above base portion 402) and a stem portion 1220 (e.g., the above stem portion 404). Stem portion 1220 extends from base portion 1218 and is coupled to the bottom of station 1212. During processing, substrate 1224 (e.g., the above substrate 417) is placed on the upper surface of base portion 1218 of pedestal 1214.

[0245] The showerhead 1216 has a base portion 1226 and a stem portion 1228. The base portion 1226 of the showerhead 1216 is cylindrical. The stem portion 1228 of the showerhead 1216 extends from the base portion 1226 of the showerhead 1216. The stem portion 1228 of the showerhead 1216 is attached to the upper plate of the station 1212. The stem portion 1228 of the showerhead 1216 receives various gases (e.g., process gas, vaporized precursor, purge gas, cleaning gas, etc.) from the gas delivery system 1250 via the manifold 1252. The base portion 1226 of the showerhead 1216 has a face plate having through holes or slots (not shown), and the gas is introduced into the station 1212 through the face plate.

[0246] The substrate processing system 1200 has a gas delivery system 1250. The gas delivery system 1250 has a gas source 1254, a valve 1256, and a mass flow controller (MFC) 1258. The gas source 1254 supplies various gases such as process gas, inert gas (also called purge gas, edge gas, carrier gas), cleaning gas, etc. The valve 1256 is connected to the gas source 1254 and can be controlled to supply gas to the MFC 1258. The MFC 1258 adjusts the flow of gas to the manifold 1252.

[0247] Furthermore, the substrate processing system 1200 also has another delivery system configured to deliver the vaporized precursor through respective valves (collectively shown as the vaporized precursor and valve 1251). The vaporized precursor and valve 1251 deliver the vaporized precursor to the manifold 1252. The manifold 1252 supplies the gas or gas mixture to the showerhead 1216.

[0248] The substrate processing system 1200 has a radio frequency (RF) power supply 1260. When plasma is used, the RF power supply 1260 supplies RF power to the showerhead 1216 during the processing of the substrate 1224 and during the cleaning of the station 1212, whether the pedestal 1214 is grounded or floating. The RF power excites the gas (e.g., process gas, vaporized precursor, cleaning gas) introduced into the station 1212 to generate plasma between the showerhead 1216 and the pedestal 1214. In some examples, the RF power supply 1260 may supply RF power to the pedestal 1214 instead of the showerhead 1216 to generate plasma, whether the showerhead 1216 is grounded or floating.

[0249] The base portion 1218 of the pedestal 1214 has a heater 1262 (e.g., the heater coil 440 described above). The heater 1262 heats the base portion 1218 of the pedestal 1214, thereby heating the substrate 1224. The base portion 1218 of the pedestal 1214 has a temperature sensor 1264 (e.g., a thermocouple connected to a conduit 484 as described above) for sensing the temperature of the pedestal 1214.

[0250] The base portion 1226 of the showerhead 1216 may also have a heater (not shown) for heating the gas introduced into the station 1212. Further, the base portion 1226 of the showerhead 1216 may also have a temperature sensor 1268 for sensing the temperature of the showerhead 1216.

[0251] The substrate processing system 1200 has another set of valves 1290 connected to the gas source 1254, an MFC and a pressure controller shown together as 1292, and a heater 1294. The edge gas and purge gas from the gas source 1254 are introduced into the pedestal 1214 via the valves 1290 (e.g., as described above, through the edge gas plenum 442, the pocket edge gas plenum 466, and the purge gas plenum 450 of the pedestal 1214).

[0252] The first and second MFCs 1292 control the flow of edge gas through the edge gas plenum 442 and the pocket edge gas plenum 466, respectively. The pressure controller 1292 controls the pressure of the purge gas supplied through the purge gas plenum 450. Specifically, the pressure controller 1292 is set to a pressure higher than the process pressure at the station 1212. As a result, the purge gas flows radially outward from under the substrate 417 toward the inside of the chamber (i.e., the volume of the station 1212 around the pedestal 1214). The flow of the purge gas prevents the diffusion of the front-side reactive gas, prevents the deposition reaction on the back side, and prevents the corrosion of the upper surface of the upper plate 416.

[0253] As described in detail above, the edge gas flows through the edge gas plenum 442 and the pocket edge gas plenum 466 to the periphery of the edge of the substrate 1224 and controls the processing (e.g., deposition, etching) at the edge (bevel) of the substrate 1224. As described in detail above, the purge gas flows under the substrate 1224 through the purge gas plenum 450 and controls the backside deposition and the diffusion of the process gas under the substrate 1224. As described in detail above, the heater 1294 heats the edge gas supplied to the pocket edge gas plenum 466.

[0254] The vacuum pump 1272 is connected to the pedestal 1214 (e.g., to the conduit 476 above) via another valve 1270. As described in detail above, in order to clamp the substrate 1224, the vacuum pump 1272 forms a vacuum on the upper surface of the pedestal 1214 by exhausting the gas in the station 1212 through the vacuum clamp plenum 472.

[0255] The substrate processing system 1210 has a controller 1280. The controller 1280 controls valves 1256, 1290, and 1270, MFCs 1258 and 1292, a pressure controller 1292, a heater 1294, a heater in pedestal 1214, a showerhead 1216, an RF power supply 1260, and a vacuum pump 1272. The controller 1280 uses temperature sensors 1264 and 1268 in the pedestal 1214 and the showerhead 1216 to monitor the temperatures of the pedestal 1214 and the showerhead 1216. The controller 1280 controls the heaters in the pedestal 1214 and the showerhead 1216 to control the temperatures of the pedestal 1214 and the showerhead 1216.

[0256] Furthermore, although not shown, the substrate processing system 1200 may further include a cooling system that supplies a refrigerant for cooling channels in the pedestal 1214 and the showerhead 1216. The controller 1280 controls the supply of the refrigerant to the cooling channels in the pedestal 1214 and the showerhead 1216 to control the temperatures of the pedestal 1214 and the showerhead 1216.

[0257] Further details of the various features of the pedestal shown and described above with reference to FIGS. 1 - 26 will be described below with reference to FIGS. 27 and 28. FIG. 27 shows a top view of the pocket 430. FIG. 28 shows an enlarged view of the inclined hole 462. Except for the additional details described below, all other details of the features identified by the same reference numerals will not be described again for the sake of brevity. The following description applies to all of the above pedestals unless otherwise specified.

[0258] In FIG. 27, for example, the pedestal described in the embodiments of the present disclosure may have at least three pockets 430 defined along the periphery of the pedestal. An example of one pocket 430 is illustrated. Each pocket 430 has a narrow portion 1300 and a wide portion 1302. The narrow portion 1300 is positioned radially inward with respect to the wide portion 1302. The tip of the narrow portion 1300 (i.e., the inner tip portion 1301 of the pocket 430) can be the narrowest portion within the narrow portion 1300 of the pocket 430. In some embodiments, the inner tip portion 1301 of the pocket 430 is located radially inward from the edge gas groove 420. The wide portion 1302 is positioned radially outward from the narrow portion 1300. The wide portion 1302 is positioned radially outward from the edge gas groove 420.

[0259] In some pedestals shown and described with reference to FIGS. 4A - 13 (however, the pedestals shown and described with reference to FIGS. 15 - 19 are not applicable), as described above with reference to FIGS. 4A - 6A, the edge gas groove 420 is positioned on the upper surface of the pedestal. Also as described above, the edge gas groove 420 is concentric with the pedestal. The edge gas groove 430 intersects the narrow portion 1300 of each pocket 430. In some examples, there are at least 30 through - holes 423 in the edge gas groove 420 and at least one through - hole 423 in the narrow portion 1300 of each pocket 430. In one example, the edge gas groove 420 has 96 through - holes 423. In some examples, the edge gas groove 420 has more than 60 through - holes 423, more than 80 through - holes 423, or more than 90 through - holes 423.

[0260] In some examples, the through-holes 423 can also be uniformly distributed radially within the edge gas groove 420. In another example, the distribution of the through-holes 423 within the edge gas groove 420 may not be uniform. For example, the first set of through-holes 423 may be closer to each other than the through-holes 423 within the second set of through-holes 423. The distance between the through-holes 423 within the first set may be smaller than the distance between the through-holes 423 within the second set. Accordingly, the through-holes 423 may be grouped into one or more clusters along the edge gas groove 420. As another example, some of the through-holes 423 can be placed near the inner wall (i.e., ID) of the edge gas groove 420, while other through-holes 423 can be placed near the outer wall (i.e., OD) of the edge gas groove 420.

[0261] The presence of a large number of through-holes 423 in the edge gas groove 420 provides several advantages. For example, more through-holes 423 provide more uniform gas delivery at the edge of the substrate 417. Further, more through-holes 423 can reduce the gap points around the outer edge portion of the substrate 417. Further, more through-holes 423 provide faster gas delivery to each point in the radial direction. For a particular application, it is preferably between 60 and 130, and in some examples preferably between 85 and 110 through-holes 423. If the number of through-holes is too large, the manufacturing cost may increase or it may be difficult to achieve a consistent arrangement of the holes. In some examples, clogging may be a problem when too many through-holes 423 are provided within the edge gas groove 420 (or when there are too many through-holes 423 that are too close to each other). Since the various through-holes of the pedestal need to operate together, the number of through-holes 423 within the edge gas groove 420 is calculated and strategically arranged to achieve the above advantages while reducing the possible adverse effects.

[0262] As described above with reference to FIGS. 4A - 6A, on the upper surface of the pedestal, the outermost (also referred to as the first) circular clamp groove 424 is positioned radially inward from the edge gas groove 420. Also as described above, on the upper surface of the pedestal, the purge gas groove 422 is positioned radially inward from the edge gas groove 420 and is also positioned between the edge gas groove 420 and the (first) circular clamp groove 424. In some embodiments, there are about 25 to 50 through - holes 446 in the purge gas groove 422. In some embodiments, there are about 30 to 40 through - holes 446 in the purge gas groove 422. In some embodiments, there are about 35 to 37 through - holes 446 in the purge gas groove 422. Some of the trade - offs discussed above with reference to the edge gas groove 420 also apply to the through - holes 446. In order to achieve an optimal / uniform purge effect under the substrate 417, it is necessary to arrange a sufficient number of through - holes 446.

[0263] In FIG. 28, in the pedestals shown in FIGS. 4A - 16, at least one inclined hole 462 is positioned within the narrow portion 1300 of each pocket 430. In some examples, not all pockets 430 have inclined holes 462 (e.g., one out of three pockets 430 has an inclined hole 462, or two out of three pockets 430 have inclined holes 462). In these examples, the other pockets 430 may not have holes around the same area or may have non - inclined holes. As can be seen from FIG. 27, the narrow portion 1300 narrows laterally along a plane parallel to the x - axis. In FIG. 28, the height of the narrow portion 1300 along the z - axis can be seen. At least one inclined hole 462 is connected to a gas delivery conduit 463. In some embodiments, the inclined hole 462 is positioned in the side wall 1304 of the narrow portion 1300 of each pocket 430 that is closest to the center of the pedestal.

[0264] Specifically, the inclined holes 462 are positioned on the radially inner sidewall 1304 of the narrow portion 1300 of each pocket 430, and the sidewall 1304 is perpendicular to the bottom surface 1306 of each pocket 430. The inclined holes 462 are positioned above at least 25% of the height h1 of the sidewall 1304 of the narrow portion 1300 of each pocket 430 that is closest to the center of the pedestal. The height h2 at which the inclined holes 462 are positioned on the sidewall 1304 is measured from the bottom surface 1306 of each pocket 430. In some examples, the inclined holes 462 are positioned above at least 50% - 75% of the height h1 of the sidewall 1304 of the narrow portion 1300 of each pocket 430. In some examples, the inclined holes 462 of one pocket may be at a different height (h2) than the height (h2) of the inclined holes 462 of an adjacent pocket 430. The advantages of arranging the inclined holes 462 at the selected height on the sidewall 1304 will be described below.

[0265] The gas delivery conduit 463 has a central axis 1310 that is not perpendicular to the sidewall 1304 of the narrow portion 1300 of each pocket 430. Perpendicular means forming a 90-degree angle with a given line, plane, or surface. Instead, the central axis 1310 of the gas delivery conduit 463 forms an acute angle 1312 with the sidewall 1304 of the narrow portion 1300 of each pocket 430. In some examples, the angle 1312 is between 20 degrees and 80 degrees. In other examples, the angle 1312 is between 30 degrees and 70 degrees, between 40 degrees and 60 degrees, or between 45 degrees and 56 degrees. In some embodiments, the gas delivery conduit 463 of one pocket forms an acute angle different from the acute angle formed with the sidewall 1304 in another pocket 430. In other words, the gas delivery conduits 463 of different pockets 430 may be formed by different reference angles.

[0266] The height and angle at which the inclined hole 462 opens into the side wall 1304 can determine the direction, trajectory, and distribution of the gas flowing out from the inclined hole 462 into the pocket 430. For example, if there is no gas flow from the inclined hole 462 into the pocket 430, the pocket region may generally create cold spots on a portion of the substrate 417 above the pocket region. The gas supplied through the inclined hole 462 positioned at the selected height and angle of the side wall 1304 can reduce or eliminate the cold spots and improve the process uniformity on the substrate 417 at a position above the pocket region of the substrate 417. The angle is selected such that the gas flowing out from the inclined hole 462 efficiently purges the finger region of the pocket 430 and also flows towards the substrate 417 to improve the uniformity. The height and angle are also selected such that for structural integrity, a certain amount of material exists above the inclined hole 462 (between the top of the inclined hole 462 and the upper surface of the pedestal).

[0267] Furthermore, the gas supplied into the pocket through the inclined hole 462 positioned at the side wall 1304 at the selected height and angle may be heated to locally increase the temperature of the substrate 417 in the region directly above the pocket 430, as described above with reference to FIG. 26, thereby improving the temperature non-uniformity of the substrate 417 in the region directly above the pocket 430 and reducing cold spots. In some embodiments, the angle of the inclined hole 462 is set to be between 45 degrees and 56 degrees for each pocket to achieve the desired uniformity.

[0268] As described above with reference to FIGS. 4A - 6A, the purge gas groove 422 also includes through holes 446. Also as described above, the purge gas groove 422 and the first clamp groove 424 include radially inwardly rounded portions 434 - 1, 434 - 2 (shown and described with reference to FIG. 6A) disposed opposite the radially inner ends (i.e., the narrow portions 1300) of their respective pockets 430.

[0269] Furthermore, as described above with reference to FIGS. 4A-6A, the pedestal further has a plurality of clamp grooves 424 positioned radially inwardly from the first clamp groove 424. The plurality of clamp grooves 424 includes a plurality of radial clamp grooves and one or more concentric clamp grooves (see, e.g., FIG. 6A). At least one of the plurality of radial clamp grooves intersects one or more concentric clamp grooves and the first clamp groove. The plurality of radial clamp grooves proximate the central portion 419 of the pedestal (see FIGS. 6A and 11A) have a plurality of through holes 490 arranged in a circular array. The clamp grooves 424 and the through holes 490 are shown and described in further detail above with reference to FIGS. 6A and 11A-11C.

[0270] As described with reference to FIGS. 6A and 11A - 11C, the plurality of radial clamp grooves 424 proximate the central portion 419 of the pedestal have one or more through - holes 490 along each of the plurality of radial clamp grooves 424. In some embodiments, the diameter of one or more through - holes 490 occupies 65% - 100% of the width of the respective radial clamp groove 424. In some examples, the diameter of one or more through - holes occupies 75% - 95% of the width of the respective radial clamp groove 424. In some examples, all of the through - holes 490 have a diameter of approximately (in this case ±5%) 0.045 inches (1.143 mm) - 0.050 inches (1.27 mm). In some examples, all of the through - holes 490 have a diameter of approximately 0.60 inches (15.24 mm) - 0.65 inches (16.51 mm). In some examples, one set of through - holes 490 has a diameter of approximately 0.45 inches (11.43 mm) - 0.50 inches (12.7 mm), while another set of through - holes 490 has a diameter of approximately 0.60 inches (15.24 mm) - 0.65 inches (16.51 mm). When the diameters of the through - holes 490 are different, the clamping force is also different. When the number of through - holes 490 is different, the clamping force is also different. Therefore, the number and diameter of the through - holes 490 can be optimized to provide a uniform clamping force for clamping the substrate 417. In embodiments where there is more than one through - hole 490 within a radial clamp groove, one through - hole 490 may be larger (in terms of diameter) or smaller than the adjacent through - hole 490. In other words, the through - holes 490 for clamping do not have to be the same size along the radial clamp groove. In some embodiments, the through - holes 490 within the same radial clamp groove have the same diameter.

[0271] Further, as can be seen from FIG. 11A, the central portion 419 of the upper surface of the pedestal has a plurality of intersection points where the plurality of radial clamp grooves 424 intersect. In some examples, the central portion 419 of the upper surface of the pedestal has two intersection points 471, 473 where five of the plurality of radial clamp grooves 424 intersect.

[0272] In some embodiments, among the plurality of radially extending clamp grooves 424 branching out from one of the plurality of intersections 471, the angle between adjacent ones is not constant (i.e., they are not all 72 degrees apart). Among the plurality of radially extending clamp grooves 424 branching out from one of the plurality of intersections 471, a first groove is 90 degrees away from a second groove adjacent to the first groove in the clockwise direction and 60 degrees away from a third groove in the counterclockwise direction. Further, among the plurality of radially extending clamp grooves 424 branching out from one of the plurality of intersections 471, a first groove is 90 degrees away from a second groove adjacent to the first groove in the clockwise direction and 90 degrees away from a third groove in the counterclockwise direction. Further, among the plurality of radially extending clamp grooves 424 branching out from one of the plurality of intersections 471, at least two adjacent grooves are separated from each other by an angle less than 90 degrees, and at least two adjacent grooves are 90 degrees apart from each other. The unique geometric pattern disclosed herein promotes clamp uniformity such that the substrate 417 is properly clamped in the desired position on the pedestal by a minimum number of through-holes 490. It is not desirable for one region under the substrate 417 to have a much stronger clamping force than another region.

[0273] At least one through-hole 490 is positioned within each of a plurality of radial clamp grooves 424 that branch out from one of the plurality of intersections 471. In some examples, where two through-holes 490 are disposed in each of the plurality of radial clamp grooves 424 that branch out from one of the plurality of intersections 471, a first set of through-holes 490 is positioned within a first circle having a first radius in each of the plurality of radial clamp grooves 424, and a second set of through-holes 490 is positioned within a second circle having a second radius in each of the plurality of radial clamp grooves. The second radius is larger than the first radius. In some examples, the first radius is 25% to 75% of the second radius. By arranging these clamp through-holes 490 in this way instead of arranging a plurality of clamp through-holes 490 near and below the periphery of the substrate, the source of the clamping force can be arranged at the center, so that the space required for passing the conduit 476 under the pedestal is reduced. Even when the distance to the periphery of the substrate increases, the through-holes 490 and the clamp grooves 424 are configured to be able to make the clamping force uniform from the central region of the pedestal.

[0274] As described above with reference to FIG. 4A, at least one of the three pockets 430 is defined within an ear of the pedestal. The ear includes a slot 1002 defined on the outer surface of the ear, and the slot 1002 is shown and described with reference to FIGS. 20A and 20B and is completely defined within a single plate. In some examples, as shown and described above with reference to FIG. 14A, the pedestal further has a plurality of ceramic springs 502 disposed on the upper surface of the pedestal.

[0275] The above description is merely exemplary in nature and is not intended to limit the present disclosure, its application, or its use. The broad teachings of the present disclosure can be implemented in various forms. Thus, although this application includes specific examples, other variations will become apparent upon review of the drawings, the specification, and the following claims, and the true scope of the present disclosure is not limited thereto.

[0276] It should be understood that one or more steps in the method may be performed in a different order (or simultaneously) without changing the principles of the present disclosure. Further, while each example is described as having certain features above, any one or more of the features described for any example of the present disclosure can be implemented in any of the other examples and / or, even if the combinations are not explicitly described, can be combined with any of the features of any of the other examples. In other words, the examples described above are not mutually exclusive, and replacing one or more examples with each other is within the scope of the present disclosure.

[0277] Spatial and functional relationships between elements (e.g., between modules, between circuit elements, between semiconductor layers) are described using various terms such as "connected", "engaged", "coupled", "adjacent", "next to", "on", "above", "below", and "disposed". When a first and a second element are described in the above disclosure, the relationship may be a direct relationship with no other intervening elements between the first and second elements, but may also be an indirect relationship with one or more intervening elements (spatially and functionally) between the first and second elements, unless explicitly stated as "direct". In this specification, the expression "at least one of A, B, and C" is to be interpreted as meaning the logical OR (A or B or C) using non-exclusive logical OR, and not as meaning "at least one A, at least one B, and at least one C".

[0278] In some implementations, the controller is part of a system, which may be part of the examples described above. Such a system may include semiconductor processing equipment, such as one or more processing tools, one or more chambers, one or more processing platforms, and / or certain processing components (such as wafer pedestals, gas flow systems, etc.). These systems may be integrated with electronic devices for controlling the operation of the system before, during, and after the processing of semiconductor wafers or substrates.

[0279] This electronic device may also be referred to as a "controller" that can control various components or sub-components of one or more systems. Depending on the processing requirements and / or the type of system, the controller may be programmed to control any of the processes disclosed herein, such as the delivery of process gases, temperature setting (e.g., heating and / or cooling), pressure setting, vacuum setting, power setting, setting of radio frequency (RF) generators, setting of RF matching circuits, frequency setting, flow rate setting, fluid supply setting, position and motion setting, loading and unloading of wafers to and from tools, and loading and unloading of wafers to and from other transfer tools and / or load locks connected or interfaced with a particular system.

[0280] Broadly speaking, the controller may be defined as an electronic device having various integrated circuits, logic, memory, and / or software that, for example, receive commands, issue commands, control operations, enable cleaning operations, and enable endpoint measurements. The integrated circuits may include chips in the form of firmware that stores program instructions, digital signal processors (DSPs), chips defined as application-specific integrated circuits (ASICs), and / or one or more microprocessors or microcontrollers that execute program instructions (such as software).

[0281] Program instructions are instructions transmitted to a controller in the form of various individual settings (or program files), which may be on or for a semiconductor wafer, or define operating parameters for performing a specific process on a system. Operating parameters may, in some instances, be part of a recipe defined by a process engineer to achieve one or more processing steps in the manufacture of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0282] In some implementations, the controller may be part of a computer integrated with, coupled to, or otherwise network-connected to the system, or may be coupled to such a computer, or a combination thereof. For example, the controller may be all or part of a host computer system within the "cloud" or a manufacturing facility that enables remote access to wafer processing. This computer can monitor the current progress of manufacturing operations, verify the history of past manufacturing operations, and verify trends or performance metrics from multiple manufacturing operations, thereby changing the parameters of the current process, setting the processing steps following the current process, or starting a new process by enabling remote access to the system.

[0283] In some examples, a remote computer (e.g., a server) can provide a process recipe to the system through a network that can include a local network or the Internet. The remote computer may include a user interface that enables input or programming of parameters and / or settings, and the parameters and / or settings are then transmitted from the remote computer to the system. In some examples, the controller receives instructions in a data format that defines the parameters of each processing step performed during one or more operations. It should be understood that this parameter may be specific to the type of process being performed and the type of tool that the controller is configured to interface with or control.

[0284] Thus, as described above, the controller may be distributed, such as by including one or more separate controllers that are network-connected to each other and operate towards a common purpose such as the processes and controls described herein. Examples of controllers distributed for such a purpose include one or more integrated circuits on a chamber that are combined to control the process on the chamber and communicate with one or more integrated circuits that are remotely located (e.g., at the platform level or as part of a remote computer).

[0285] By way of non-limiting example, an exemplary system may include a plasma etching chamber or module, a deposition chamber or module, a spin rinse chamber or module, a metal plating chamber or module, a clean chamber or module, a bevel edge etching 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 etching (ALE) chamber or module, an ion implantation chamber or module, a track chamber or module, and any other semiconductor processing system that may be associated with or used in the manufacture and / or production of semiconductor wafers.

[0286] As described above, depending on one or more process steps performed by a tool, the controller may communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the factory, a main computer, other controllers, or one or more of the tools used for material handling that carry a wafer container to and / or from a tool location and a load port within a semiconductor manufacturing facility.

Claims

1. A substrate support, at least three pockets defined along the periphery of the substrate support, each pocket having a narrow portion and a wide portion positioned radially outward from the narrow portion, at least three pockets; an edge gas groove positioned on the upper surface of the substrate support, concentric with the substrate support, intersecting the narrow portion of each pocket, having at least 30 through holes in the edge gas groove and at least one through hole in the narrow portion of each pocket, an edge gas groove; a first clamp groove positioned radially inward from the edge gas groove on the upper surface of the substrate support; A substrate support having the above.

2. The substrate support according to claim 1, at least one inclined hole positioned in at least one of the narrow portions of the at least three pockets, connected to a gas delivery conduit, at least one inclined hole; a purge gas groove positioned between the edge gas groove and the first clamp groove on the upper surface of the substrate support; A substrate support further having the above.

3. The substrate support according to claim 2, wherein the edge gas groove, the purge gas groove, and the first clamp groove are concentric.

4. The substrate support according to claim 2, for at least one of the at least three pockets, the inclined holes are positioned on the radially inner side wall of the narrow portion of each pocket, and the radially inner side wall of the narrow portion is the surface of the pocket closest to the center of the substrate support.

5. The substrate support according to claim 4, wherein the radially inner side wall is perpendicular to the bottom surface of each pocket.

6. The substrate support according to claim 4, the inclined holes are positioned above at least 25% of the height of the radially inner side wall of the narrow portion of each pocket, the height being measured from the bottom surface of each pocket.

7. The substrate support according to claim 6, wherein the inclined holes are positioned above at least 50% - 75% of the height of the radially inner side wall of the narrow portion of the pocket.

8. The substrate support according to claim 4, wherein the gas delivery conduit has a central axis that is not perpendicular to the radially inner side wall of the narrow portion of each pocket.

9. The substrate support according to claim 8, wherein the central axis of the gas delivery conduit forms an acute angle with the radially inner side wall of the narrow portion of the pocket.

10. The substrate support according to claim 9, wherein the acute angle is between 20 degrees and 80 degrees.

11. The substrate support according to claim 9, wherein the acute angle is between 30 degrees and 70 degrees.

12. The substrate support according to claim 9, wherein the acute angle is between 40 degrees and 60 degrees.

13. The substrate support according to claim 2, wherein the purge gas groove includes one or more through holes.

14. The substrate support according to claim 2, wherein the purge gas groove and the first clamp groove are radially aligned at the inner end of each pocket and have an inwardly rounded portion.

15. The substrate support according to claim 2, further comprising a plurality of clamp grooves positioned radially inward from the first clamp groove, the plurality of clamp grooves having a plurality of radial clamp grooves and one or more concentric clamp grooves, wherein at least one of the plurality of radial clamp grooves intersects at least one concentric clamp groove and the first clamp groove.

16. The substrate support according to claim 15, wherein the plurality of radial clamp grooves proximate the central portion of the substrate support have a plurality of through holes arranged in a circular array.

17. The substrate support according to claim 15, wherein the plurality of radial clamp grooves proximate the central portion of the substrate support have one or more through holes along each of the plurality of radial clamp grooves.

18. The substrate support according to claim 17, wherein the diameter of the one or more through holes occupies 55% to 90% of the width of each respective radial clamp groove.

19. The substrate support according to claim 2, wherein at least one of the three pockets is defined in an ear portion of the substrate support, and the ear portion of the substrate support includes a slot defined in an outer surface of the ear portion. The substrate support in which the slot is completely defined within a single plate.

20. The substrate support according to claim 2, further comprising a plurality of ceramic springs disposed on the upper surface of the substrate support.

21. The substrate support according to claim 1, further comprising a plurality of clamp grooves positioned radially inward from the first clamp groove, the plurality of clamp grooves having a plurality of radial clamp grooves and one or more concentric clamp grooves, wherein at least one of the plurality of radial clamp grooves intersects the one or more concentric clamp grooves and the first clamp groove.

22. The substrate support according to claim 21, wherein the plurality of radial clamp grooves proximate the central portion of the substrate support have a plurality of through-holes arranged in a circular array.

23. The substrate support according to claim 21, wherein the plurality of radial clamp grooves proximate the central portion of the substrate support have one or more through-holes along each of the plurality of radial clamp grooves.

24. The substrate support according to claim 23, wherein the diameter of the one or more through-holes occupies 55% to 90% of the width of each of the radial clamp grooves.

25. The substrate support according to claim 1, wherein at least one of the three pockets is defined in the ear portion of the substrate support, the ear portion of the substrate support includes a slot defined on the outer surface of the ear portion, and the slot is completely defined within a single plate.

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