Improved susceptor for process chamber

Abstract

A substrate support assembly is provided, which includes a susceptor assembly. The susceptor assembly includes an inner body, an outer rim positioned around the inner body, and an inner portion having a plurality of recesses, each recessed relative to the lower surface of the inner body, and an outer portion positioned around the inner portion, which includes an inner shelf. The outer rim of the inner portion is positioned on the inner shelf of the outer portion, and the substrate support assembly further includes a first plurality of lift pins. Each of the first plurality of lift pins is located below one of the recesses of the inner portion of the susceptor assembly.

Description

[Technical Field]

[0001]

[0001] Embodiments of the present disclosure relate more broadly to improved susceptors used in process chambers, such as semiconductor process chambers. [Background technology]

[0002]

[0002] Susceptors are often used when performing processes (such as deposition) on substrates such as semiconductor substrates. During the process, the substrate is placed on the susceptor. Susceptors are often replaced with new or different susceptors, for example, to perform a different process or when process performance is outside of specifications. This is because the process can be very sensitive to the characteristics of the susceptor (for example, changes in the surface emissivity of the susceptor can affect thermal performance, or particles may be generated from a degraded susceptor). Since replacing a susceptor involves extensive disassembly and re-checking of the equipment, this replacement can result in a long downtime of the equipment (e.g., several hours or several days).

[0003]

[0003] Therefore, there is a need for improved methods and equipment for susceptor replacement that can reduce the downtime caused by susceptor replacement. [Overview of the project]

[0004]

[0004] In one embodiment, the substrate support assembly is a susceptor assembly comprising an inner body, an outer rim disposed around the inner body, and an inner portion comprising a plurality of recesses, each recess being recessed relative to the lower surface of the inner body, and an outer portion disposed around the inner portion, the outer portion comprising an inner shelf, the outer rim of the inner portion being disposed on the inner shelf of the outer portion, and a first plurality of lift pins, each of the first plurality of lift pins being located below one of the recesses of the inner portion of the susceptor assembly.

[0005]

[0005] In another embodiment, the susceptor assembly comprises an inner body, an outer rim positioned around the inner body, and an inner portion including a plurality of recesses, each recess being recessed relative to the lower surface of the inner body, and an outer portion positioned around the inner portion, the outer portion including an inner shelf, the outer rim of the inner portion positioned on the inner shelf of the outer portion.

[0006]

[0006] In another embodiment, a process chamber for processing a substrate comprises a body enclosing an internal space, an opening configured for transporting a substrate into the internal space, and a susceptor assembly comprising an outer portion and an inner portion on the outer portion, wherein the outer portion is positioned around the inner portion and the inner portion is transported through the opening.

[0007]

[0007] In order to understand the features of the present disclosure described above in detail, the present disclosure, which has been briefly summarized above, will be described more specifically with reference to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings only show exemplary embodiments and should not be considered to limit the scope of the present disclosure, and other equally valid embodiments may also be permitted. [Brief explanation of the drawing]

[0008] [Figure 1A]

[0008] This is a schematic cross-sectional view of a processing system according to one embodiment. [Figure 1B]

[0009] This is an enlarged cross-sectional view of section 1B of Figure 1A, showing further details of a substrate support assembly according to one embodiment. [Figure 1C]

[0010] This is a schematic top view of a substrate support assembly according to one embodiment. [Figure 1D]

[0011] This is a side cross-sectional view of a substrate support assembly in a first position, according to one embodiment, which allows a robot end effector to transfer the substrate to and from a susceptor assembly. [Figure 1E]

[0012] This is a side cross-sectional view of a substrate support assembly in a second position, according to one embodiment, which allows the inner portion of the susceptor assembly to be transported to and from the internal space of the process chamber by a robot end effector. [Figure 1F]

[0013] This is a side cross-sectional view of several components of a process chamber from Figure 1A, according to one embodiment. [Figure 2]

[0014] This is a top view of an alternative susceptor assembly used as part of a substrate support assembly according to one embodiment. [Figure 3A]

[0015] This is a top view of an alternative susceptor assembly used with an alternative substrate support assembly according to one embodiment. [Figure 3B]

[0016] This is a side cross-sectional view showing a substrate lifted above the susceptor assembly by a substrate support assembly according to one embodiment. [Figure 3C]

[0017] This is a side cross-sectional view showing the inner portion of the susceptor assembly that has been lifted above the outer portion by the substrate support assembly, according to one embodiment. [Modes for carrying out the invention]

[0009]

[0018] For ease of understanding, the same reference numerals have been used to indicate identical elements common to multiple figures, where possible. It is assumed that elements and features of one embodiment may be usefully incorporated into other embodiments without further description.

[0010]

[0019] Multiple embodiments of this disclosure relate, more broadly, to improved substrate support assemblies and susceptor assemblies used in the processing of substrates (e.g., semiconductor substrates). The susceptor assembly includes an outer portion and a removable inner portion. The inner portion may be sized to be transported into the process chamber through the same opening through which the substrate is transported into the process chamber. The inner portion may be lifted above the outer portion using lift pins on the substrate support assembly to allow the inner portion to be removed from the chamber, for example, by using the same robot that removes the substrate from the process chamber. The removable inner portion may fit through the same opening as the substrate, so that a new susceptor assembly can be used with existing equipment.

[0011]

[0020] By enabling the replacement of the inner portion of the susceptor using equipment within the processing system (e.g., a robot), downtime traditionally associated with susceptor cleaning or susceptor replacement for production runs using different susceptors can be avoided. The ability to automatically transfer the susceptor can be added without significantly increasing the footprint or capital cost of the processing system by using the same equipment (e.g., the same transfer robot) and the same non-equipmental components (e.g., the same slit valve opening in the process chamber) to transfer both the substrate and the inner portion of the susceptor. Furthermore, since the inner portion of the susceptor can be replaced within the process chamber, it becomes substantially easier to perform shorter production runs using different process applications that may require different susceptors. Replacing the inner portion of the susceptor also makes troubleshooting potential susceptor-related problems substantially easier. Furthermore, since the susceptors are replaced using automated equipment, errors associated with manual handling of the susceptors may be reduced or eliminated, while handling consistency and the precision of susceptor placement may be improved, which could lead to improved product uniformity of the substrates processed on the susceptors.

[0012]

[0021] FIG. 1A is a schematic cross-sectional view of a processing system 100 according to one embodiment. The processing system 100 includes a process chamber 101 and a controller 175. The processing system 100 may be configured to perform an epitaxial deposition process within the process chamber 101. Although the present disclosure primarily describes an improved susceptor used within an epitaxial deposition chamber, the benefits of the present disclosure may be more broadly applicable to any substrate support used in semiconductor processing or other processing.

[0013]

[0022] The process chamber 101 includes a housing structure 102 made of a process-resistant material such as aluminum or stainless steel (e.g., 316L stainless steel). The housing structure 102 surrounds various functional elements of the process chamber 101, such as a quartz chamber 104 that includes an upper quartz chamber 105 and a lower quartz chamber 106. The quartz chamber 104 surrounds an internal space 110 (also referred to as a process space). One or more liners 108, 109 may isolate the quartz chamber 104 from the housing structure 102.

[0014]

[0023] The process chamber 101 includes a substrate support assembly 120. The substrate support assembly 120 includes a substrate support 130. The substrate 50 may be disposed on the susceptor assembly 130 during processing such as during deposition.

[0015]

[0024] The process chamber 101 may further include an upper lamp module 164A and a lower lamp module 164B for heating the substrate 50 and / or the internal space 110. In one embodiment, the upper lamp module 164A and the lower lamp module 164B are infrared (IR) lamps.

[0016]

[0025] The substrate support assembly 120 may include an actuator 119, an outer shaft 121, and an inner shaft 122. The actuator 119 is configured to move the inner shaft 122 perpendicularly to the outer shaft 121. The actuator 119 is further configured to rotate the inner shaft 122 while the outer shaft 121 remains stationary. The inner shaft 122 is configured to rotate around a central axis C that extends perpendicularly through the center of the inner shaft 122.

[0017]

[0026] The substrate support assembly 120 further includes a susceptor assembly 130, a support plate 125, and a plurality of support pins 126 (for example, three support pins 126 positioned 120 degrees apart from each other at the same distance from the central vertical axis C). Further details regarding these components are shown in Figure 1B. In one embodiment, the support plate 125 and the support pins 126 may be made of quartz or silicon carbide. The support plate 125 is positioned on the inner shaft 122 (for example, directly). The support plate 125 may include a center 125C aligned with the central vertical axis C. Each of the support pins 126 is positioned on the support plate 125 (for example, directly). The susceptor assembly 130 is positioned on the support pins 126 (for example, directly).

[0018]

[0027] The susceptor assembly 130 includes an outer portion 131 and an inner portion 150. The inner portion 150 is positioned on and supported by the outer portion 131. The inner portion 150 can be easily moved (e.g., lifted) away from the outer portion 131, as will be described in more detail below. In some embodiments, the inner portion 150 and the outer portion 131 may be formed of silicon carbide-coated graphite. In one embodiment, the outer portion 131 may have a ring shape. The outer portion 131 may be positioned around the inner portion 150. The inner portion 150 may be positioned on a portion of the outer portion 131, as will be described in more detail below. The process chamber 101 may further include a preheating ring 114, which may be positioned around the susceptor assembly 130.

[0019]

[0028] The substrate support assembly 120 further includes a first plurality of lift pins 140A and a second plurality of lift pins 140B. For the sake of simplicity in the drawings, only one of each lift pin 140A, 140B is shown in Figure 1A. In one embodiment, the first plurality of lift pins 140A and the second plurality of lift pins 140B may be formed of quartz. In one embodiment, the first plurality of lift pins 140A may consist of three lift pins 140A 1-3 Including a second set of lift pins 140B, the three lift pins 140B 1-3 This includes. Other embodiments may include two lift pins of each type or four or more lift pins of each type.

[0020]

[0029] A first set of lift pins 140A may be positioned and configured to lift the substrate 50 above the susceptor assembly 130 in order to allow the substrate 50 to be transported to and from the internal space 110 of the process chamber 101. A second set of lift pins 140B may be positioned and configured to lift the inner portion 150 of the susceptor assembly 130 above the outer portion 131 of the susceptor assembly 130 in order to allow the inner portion 150 of the susceptor assembly 130 to be transported to and from the internal space 110 of the process chamber 101.

[0021]

[0030] The substrate support assembly 120 may further include three lift pin pads 123. Several other embodiments may include more or fewer lift pin pads (e.g., two lift pin pads). Each lift pin pad 123 may be mounted on the outer shaft 121. In one embodiment, the lift pin pads 123 may be made of quartz.

[0022]

[0031] The lift pin pads 123 can be positioned 120 degrees apart from each other with respect to a central axis C extending through the center of the outer shaft 121. The first lift pin pad 1231 and the second lift pin pad 1232 are shown in Figure 1A. The third lift pin pad 1233 is not visible in Figure 1A. Each of the lift pin pads 123 is also positioned at the same distance from the central axis C as the respective distances of the lift pins 140A and 140B from the center 125C of the support plate 125. As will be described in more detail below, the position of the lift pin pads 123 is such that the substrate support assembly 120 has (1) a plurality of first lift pins 140A 1-3 (1) Each of the lift pins is positioned at a board lifting position (first position) above one of the lift pin pads 123, or (2) a second set of lift pins 140B 1-3 Each of these allows the support plate 125 to rotate to an inner susceptor lift position (second position) above one of the lift pin pads 123. As used herein, “overlies” and “underlies” refer to components that have different vertical positions but whose horizontal positions in the respective XY planes overlap to some extent.

[0023]

[0032] As will be described in more detail below, when the support plate 125 is in the substrate-lifting position, the actuator 119 can lower the inner shaft 122 to bring the lift pins 140A into contact with the lift pin pads 123 and use the movable lift pin caps to push the substrate 50 upwards over the inner portion 150 of the susceptor assembly 130. When the actuator 119 lowers the inner shaft 122 to bring the first set of lift pins 140A into contact with the lift pin pads 123 while the support plate 125 is in the substrate-lifting position, the second set of lift pins 140B do not come into contact with any of the lift pin pads 123, but instead move closer to the lower quartz chamber 106 (see Figure 1D).

[0024]

[0033] As will be described in more detail below, when the support plate 125 is in the inner susceptor raised position, the actuator 119 can lower the inner shaft 122, bringing the lift pins 140B into contact with the lift pin pads 123, and pushing the inner portion 150 of the susceptor assembly 130 upwards from the outer portion 131. When the actuator 119 lowers the inner shaft 122 to bring the second set of lift pins 140B into contact with the lift pin pads 123 while the support plate 125 is in the inner susceptor raised position, the first set of lift pins 140A do not come into contact with any of the lift pin pads 123, but instead move closer to the lower quartz chamber 106 (see Figure 1E).

[0025]

[0034] In one embodiment, one or more of the lift pin pads 123 may include a sensor (e.g., a proximity sensor) connected to the controller 175 to detect when one of the lift pins 140A, 140B is above the lift pin pad 123. The controller 175 can use feedback from the sensor to stop the rotation of the support plate 125 by the actuator 119. This allows the controller to align a first set of lift pins 140A above the lift pin pad 123 to lift the substrate 50, or to align a second set of lift pins 140B above the lift pin pad 123 to lift the inner portion 150.

[0026]

[0035] In one embodiment, the process chamber 101 may include an encoder 180. In one embodiment, the encoder may be mounted outside the inner shaft 122, such as near the bottom of the inner shaft 122. The encoder 180 can be used to control the amount of angle (e.g., 60 degrees, 90 degrees, 180 degrees, etc.) by which the susceptor assembly 130 rotates from its home position. By identifying and controlling this angular rotation of the inner shaft 122, the susceptor assembly 130 can be rotated to any angle from its home position. This provides the ability to rotate the susceptor assembly 130 and the substrate 50 to angular positions such as a first position where the lift pin pad 123 is aligned with a first plurality of lift pins 140A, and a second position where the lift pin pad 123 is aligned with a second plurality of lift pins 140B.

[0027]

[0036] The processing system 100 also includes a controller 175 for controlling the processes performed by the processing system 100. The controller 175 may be any type of controller used in industrial settings, such as a programmable logic controller (PLC). The controller 175 includes a processor 177, memory 176, and input / output (I / O) circuits 178. The controller 175 may further include one or more of the following components (not shown), such as one or more power supplies, a clock, communication components (e.g., a network interface card), and a user interface, which is typical for controllers for semiconductor devices.

[0028]

[0037] Memory 176 may include non-temporary memory. Non-temporary memory can be used to store programs and settings as described below. Memory 176 may include one or more readily available types of memory, such as read-only memory (ROM) (e.g., electrically erasable programmable read-only memory (EEPROM)), flash memory, floppy disks, hard disks, or random-access memory (RAM) (e.g., non-volatile random-access memory (NVRAM)).

[0029]

[0038] The processor 177 is configured to execute various programs stored in memory 176, such as epitaxial deposition processes and processes for transferring the substrate and susceptor to and from the internal space 110, as will be described in more detail below. While these programs are being executed, the controller 175 may communicate with I / O devices via I / O circuitry 178. For example, while these programs are being executed and communicating via I / O circuitry 178, the controller 175 may control outputs, such as the rotational position of the susceptor assembly 130 relative to the lift pin pad 123 or the vertical position of the susceptor assembly 130, via the use of actuator 119. Memory 176 may further include various operating settings used to control the processing system 100.

[0030]

[0039] Figure 1B is an enlarged cross-sectional view of section 1B of Figure 1A, showing further details of the substrate support assembly 120 according to one embodiment.

[0031]

[0040] The support plate 125 may include six holes 125H, each hole 125H configured to receive one of six lift pins 140A, 140B. Figure 1B shows a first lift pin 140A1 extending through a first hole 125H1 and a second lift pin 140B1 extending through a fourth hole 125H4. In some embodiments, each of the first plurality of lift pins 140A and the second plurality of lift pins 140B may be identical. Referring to the first lift pin 140A1, each lift pin 140A, 140B may include an upper portion 141 and a lower portion 142. The lower end of the upper portion 141 includes a stop 143 sized not to fit into the corresponding hole 125H (with the stop 143 on top). The lower portion 141 includes an upper end 145. The upper end of the lower portion 142 includes a tapered portion 144 configured to fit inside the corresponding hole 125H of the support plate 125.

[0032]

[0041] The outer portion 131 of the susceptor assembly 130 includes an inner shelf 135 and an outer body 134 positioned around the inner shelf 135. The outer body 134 includes an inner edge 136. The inner shelf 135 extends inward from the inner edge 136 of the outer body 134 to the inner edge 137 of the inner shelf 135. The upper surface 133 of the inner shelf 135 is positioned below the upper surface 132 of the outer body 134. The outer portion 131 may include a flat lower surface 139 extending over the lower surfaces of the outer body 134 and the inner shelf 135.

[0033]

[0042] The inner portion 150 of the susceptor assembly 130 includes an inner body 154 and an outer rim 153 positioned around the inner body 154. The outer rim 153 includes an outer edge 155. The outer rim 153 may be sized such that the outer edge 155 fits just inside the inner edge 136 of the outer body 134 of the outer portion 131. The inner body 154 includes an outer edge 156. The inner body 154 may be sized such that the outer edge 156 fits just inside the inner edge 137 of the inner shelf 135 of the outer portion 131.

[0034]

[0043] When the inner portion 150 is positioned inside the outer portion 131, the lower surface 159 of the outer rim 153 may be positioned on the upper surface 133 of the inner shelf 135 of the outer portion 131. In some embodiments, the upper surface 151 of the inner portion 150 may be substantially flat except for the holes for the lift pin caps as described below. In some embodiments, the upper surface 151 may include pockets positioned to be spaced apart from most of the lower surface of the substrate 50 during processing. In some embodiments, when the inner portion 150 is positioned inside the outer portion 131, the upper surface 151 of the inner portion 150 may be configured to be flush with the upper surface 132 of the outer body 134 of the outer portion 131. As will be described in more complete detail below, the lower surface 152 of the inner body 154 may be substantially flat except for the holes 157 for the lift pin caps 165 and the recesses 168 for lifting the inner portion 150. The lower surface 152 may be flush with the lower surface 139 of the outer portion 131.

[0035]

[0044] In some embodiments, the inner body 154 may include a tapered design to assist in centering the inner portion 150 within the opening of the outer portion 131. For example, the outer edge 156 of the inner body 154 may be narrower at the bottom than at the top of the inner edge 156. In one embodiment, the inner body 154 has an inverted conical shape similar to the lift pin cap 165, which will be described in more detail below. The opening enclosed by the inner edge 137 of the inner shelf 135 of the outer portion 131 may also be wider at the top and narrower at the bottom to assist in centering the inner body 154 of the inner portion 150 within the opening of the outer body 131. Furthermore, in some embodiments, the inner portion 150 may have a different surface finish than the outer portion 131 in order to control heat conduction between the two components 131, 150 during processing. Furthermore, many different types of inner portions 150, each having a different surface finish, may be configured to be used with a single outer portion 131, allowing the thermal properties of the susceptor assembly 130 to be adjusted when an inner portion 150 having a first surface finish is replaced with an inner portion 150 having a different surface finish. Surface finish is just one example of the features of the inner portion 150 that can be adjusted. Several other features that can be adjusted include, but are not limited to, the depth of the substrate pocket (i.e., the distance between the bottom of the substrate and the top surface of the inner portion) and the composition of the material used to form the inner portion 150.

[0036]

[0045] The inner portion 150 of the susceptor assembly 130 may include a plurality of holes 157, such as three holes 157. A first hole 1571 is shown in Figure 1B. Each hole 157 is located above one of the lift pins 140A. The susceptor assembly 130 may further include three lift pin caps 165. Each lift pin cap 165 is configured to fit inside one of the holes 157. In some embodiments, the lift pin caps 165 may be formed from the same (one or more) materials as the inner portion 150 of the susceptor assembly 130. This may help improve thermal uniformity during processing. In some embodiments, the lift pin caps 165 may be formed from glassy carbon or graphite coated with silicon carbide.

[0037]

[0046] A first lift pin cap 1651 is shown in Figure 1B within a first hole 1571. Each hole 157 extends from the lower surface 152 to the upper surface 151 of the inner body 154. Each lift pin cap 165 includes a recess 166 on its underside for receiving one of the lift pins 140A. Each recess 166 may have a tapered profile (e.g., wider at the bottom of the recess than at the top of the recess) to assist in aligning the lift pin 140A into each corresponding recess 166. Each of the lift pins 140A may fit inside the recess 166 and be lifted relative to the support plate 125 to lift the lift pin cap 165 above the upper surface 151 of the inner portion 150 of the susceptor assembly 130. By lifting the lift pin cap 165 above the upper surface 151, the substrate 50 is lifted above the upper surface 151 of the inner portion 150 of the susceptor assembly 130, allowing the substrate 50 to be removed from the internal space 110, for example, by a robot (not shown). Each lift pin cap 165 and the corresponding hole 157 may have a tapered shape. This makes the lower portion of the lift pin cap 165 substantially smaller than the upper surface of the lift pin cap 165 and substantially smaller than the upper portion of the corresponding hole 157. This tapered design helps the lift pin cap 165 to fit more easily into the corresponding hole 157 when it is lowered into the hole 157, and helps guide the lift pin cap 165 to a central position within the hole 157. In one embodiment, each lift pin cap 165 has an inverted cone shape.

[0038]

[0047] The inner portion 150 may further include a plurality of recesses 168, such as three recesses 168. A first recess 1681 is shown in Figure 1B. Each recess 168 is recessed into the lower surface 152 of the inner body 154 of the inner portion 150. Each of the recesses 168 is located on one of the lift pins 140B. The lift pins 140B are configured to lift the inner portion 150 of the susceptor assembly 130 above the outer portion 131 of the susceptor assembly 130. Each of the lift pins 140B may be lifted relative to the support plate 125 to fit inside one of the corresponding recesses 168 in order to lift the inner portion 150 of the susceptor assembly 130 above the outer portion 131. By lifting the inner portion 150 above the outer portion 131, the inner portion 150 can be removed from the internal space 110, for example, by a robot (not shown). Each recess 168 may have a tapered profile (for example, wider at the bottom of the recess than at the top) to help align the lift pin 140B with each corresponding recess 168.

[0039]

[0048] Figure 1C is a schematic top view of a substrate support assembly 120 according to one embodiment. The view in Figure 1C shows the location of different components within the substrate support assembly 120. The inner portion 150 of the susceptor assembly 130 is located inside the outer portion 131 of the susceptor assembly 130, for example, as shown in Figure 1B. Dashed lines are used to indicate the location of some components that would not be visible in the top view of the susceptor assembly 130.

[0040]

[0049] The three lift pin caps 1651 - 1653 can be arranged such that they are separated from each other by 120 degrees (also referred to as the first angular difference) with respect to the central axis C (FIG. 1A) extending through the center 150C of the inner portion 150 of the susceptor assembly 130. Each lift pin cap 165 is positioned at a distance D (the first distance) from the center 150C of the inner portion 150. Each lift pin 140A1 - A3 from the first plurality of lift pins is beneath the corresponding lift pin cap 1651 - 1653. Thus, each lift pin 140A1 - A3 is also arranged such that it is separated from the other two lift pins 140A by 120 degrees (also referred to as the first angular difference) with respect to the central axis C, and each lift pin 140A1 - A3 is positioned at the same distance D from the vertical central axis C as the lift pin cap 165.

[0041]

[0050] The three recesses 1681 - 1683 can be arranged such that they are separated from each other by 120 degrees (also referred to as the first angular difference) with respect to the central axis C (FIG. 1A) extending through the center 150C of the inner portion 150 of the susceptor assembly 130. Each recess 168 is also positioned at a distance D from the center 150C of the inner portion 150. Each lift pin 140B1 - 140B3 from the second plurality of lift pins is beneath the corresponding recess 1681 - 1683. Thus, each lift pin 140B1 - 140B3 is also arranged such that it is separated from the other two lift pins 140B by 120 degrees (also referred to as the first angular difference) with respect to the central axis C, and each lift pin 140B1 - 140B3 is positioned at the same distance D from the vertical central axis C as the lift pin cap 168.

[0042]

[0051] Each of the lift pins 140A 1-3 is arranged (1) 60 degrees clockwise from one of the lift pins 140B 1-3 with respect to the central axis C, and (2) 60 degrees counterclockwise from another one of the lift pins 140B 1-3 with respect to the central axis C. Similarly, each of the lift pins 140B 1-3 is (1) with respect to the central axis C, 140A 1-3(2) Lift pin 140A is positioned 60 degrees away from one of the central axes C 1-3 It is positioned 60 degrees counterclockwise from another one of them.

[0043]

[0052] The three lift pin pads 1231-1233 can each be positioned at a distance of 120 degrees from each other (also called the first angular difference) with respect to the central axis C (Figure 1A) which extends through the center of the inner shaft 122 and the center 150C of the susceptor assembly 130. Each lift pin pad 123 is also positioned at the same distance D from the central axis C as the lift pins 140A and 140B. Each lift pin pad 123 can be stationary. The lift pin pads 123 are positioned 120 degrees apart from each other with respect to the central axis C, and each lift pin pad 123 is positioned at the same distance D from the central axis C as the lift pins 140A, 140B, lift pin caps 165, and recesses 168, so that the support plate 125 (see Figure 1A) and the susceptor assembly 130 can be rotated by the actuator 119 to (1) a first position where each of the lift pins 140A and lift pin caps 165 is on the corresponding lift pin pad 123, as shown in Figure 1C, or (2) a second position where each of the lift pins 140B and recesses 168 is on the corresponding lift pin pad 123 (not shown). Next, the actuator 119 can lower the inner shaft 122 in a first position to cause a first set of lift pins 140A to lift the substrate 50 onto the inner portion 150 of the susceptor assembly 130, as shown in Figure 1D, or (2) lower the inner shaft 122 in a second position to cause a second set of lift pins 140B to lift the inner portion 150 of the susceptor assembly 130 onto the outer portion 131 of the susceptor assembly 130, as shown in Figure 1E.

[0044]

[0053] Figure 1D is a side cross-sectional view of a substrate support assembly 120 in the first position described above with reference to Figure 1C, according to one embodiment, which allows the substrate 50 to be transferred to and from the susceptor assembly 130 by the robot end effector 60. During operation, the substrate 50 is lifted above the inner portion 150 of the susceptor assembly 130 by each of the three lift pins 140A. For the sake of drawing simplification, only one lift pin 140A and the lift pin pad 123 are shown in Figure 1D. While the lift pin 140A is lifting the substrate 50 above the inner portion 150 of the susceptor assembly 130, the lower portion of the other lift pin 140B may extend below the upper part of the lift pin pad 123.

[0045]

[0054] Figure 1E is a side cross-sectional view of a substrate support assembly 120 in the second position described above with reference to Figure 1C, according to one embodiment, which allows the inner portion 150 to be transported to and from the internal space 110 of the process chamber 101 by the robot end effector 60. During operation, the inner portion 150 is lifted above the outer portion 131 of the susceptor assembly 130 by each of the three lift pins 140B. For the sake of drawing simplification, only one lift pin 140B and one lift pin pad 123 are shown in Figure 1E. While lift pin 140B is lifting the inner portion 150 above the outer portion 131 of the susceptor assembly 130, the lower portion of the other lift pin 140A may extend below the upper part of the lift pin pad 123.

[0046]

[0055] In one embodiment, the substrate 50 and the inner portion 150 can be lifted simultaneously. For example, the substrate 50 is added on top of the inner portion 150 shown in Figure 1E. In several such embodiments, the robot end effector 60 can simultaneously remove the substrate 50 and the inner portion 150 from the internal space 110 of the process chamber 101, or simultaneously insert a new substrate 50 and inner portion 150 into the internal space 110 of the process chamber 101.

[0047]

[0056] Figure 1F is a side cross-sectional view of some components of the process chamber 101 from Figure 1A according to one embodiment. Figure 1F shows the susceptor assembly 130 and the preheating ring 114 positioned above the opening 190 of the process chamber 101. The portion of the substrate support assembly 120 below the susceptor assembly 130 is omitted for clarity. The opening 190 may be a slit valve opening of the process chamber 101. This slit valve opening is configured to allow the transfer of the substrate 50 and the inner portion 150 of the susceptor assembly 130 through the opening 190. Although not required, the opening 190 may have a rectangular cross-section in a vertical plane, such as the vertical plane in Figure 1F. The opening 190 may have a height 190H and a width 190W in a vertical plane. The inner portion 150 of the susceptor assembly 130 may have a width 150W and a height 150H when the inner portion 150 is positioned on the outer portion 131. The height 150H can be the highest point of the inner portion 150 across its width 150W. The height 190H of the opening 190 is greater than the height 150H of the inner portion 150. Similarly, the width 190W of the opening 190 is greater than the width 150W of the inner portion 150. Since the cross-sectional dimensions of the opening 190 are larger than the cross-sectional dimensions of the corresponding inner portion 150, the inner portion 150 can move through the opening 190. This allows the inner portion 150 of the susceptor assembly 130 to be replaced in the same manner as the substrate 50. For example, as described above in Figures 1D and 1E, the transfer between the substrate 50 and the inner portion 150 of the susceptor assembly 130 can be performed using the end effector 60.

[0048]

[0057] Figure 2 is a top view of an alternative susceptor assembly 230 used as part of a substrate support assembly 220 according to one embodiment. The substrate support assembly 220 is the same as the substrate support assembly 120 described above, except that the substrate support assembly 220 includes a susceptor assembly 230 instead of the susceptor assembly 130 described above. The susceptor assembly 230 is the same as the susceptor assembly 130 described above, except that the susceptor assembly 230 includes an outer portion 231 and an inner portion 250 having different shapes and sizes compared to the corresponding outer portion 131 and inner portion 150 of the susceptor assembly 130 described above.

[0049]

[0058] The inner portion 150 described above had a circular outer profile when viewed from a top view (see Figure 1C). Conversely, the inner portion 250 has an outer profile that is partially circular and partially rectangular. The top surface 251 of the inner portion 250 may have a width 250W in the X direction and a length 250L in the Y direction. In some embodiments, the length 250L may be the longest dimension across the top surface 251 of the inner portion 250. In some embodiments, the width 250W may be the shortest dimension across the top surface 251 of the inner portion 250. The width 250W may be sized to fit through the opening of the process chamber (e.g., a slit valve opening) used to transfer the substrate into the process chamber. In one embodiment, the width 250W is the same as or within a few percent of a typical dimension of a standard wafer, such as 300 mm. In some embodiments, the length 250L is at least 10% larger than the width 250W, for example, at least 25% larger, for example, at least 50% larger. By making the width 250W substantially smaller than the length 250L, the inner portion 250 may be transported through a smaller opening. For example, the opening is sized to be slightly larger than the dimensions of the substrate being transported through the opening. By making the length 250L substantially longer than the width 250W, more of the inner portion 250 of the susceptor assembly (e.g., a larger surface area) may have properties specific to a given inner portion 250 (e.g., composition, surface roughness, etc.). This is useful not only for cleaning more of the susceptor assembly when the inner portion 250 is replaced, but may also be beneficial for performing different recipes. The susceptor assembly 230 may also include a substrate pocket 255 configured to receive a substrate 50. The substrate pocket 255 may have the same shape as the substrate being processed (e.g., circular). In one embodiment, the substrate pocket 255 has a diameter that is the same as or within a few percent of the width 250W described above.

[0050]

[0059] Figure 3A is a top view of an alternative substrate support assembly 330 used with the alternative substrate support assembly 320 according to one embodiment. The substrate support assembly 330 is the same as the susceptor assembly 130 described above, except that the susceptor assembly 330 includes an inner portion 350 instead of the inner portion 150 described above. The inner portion 350 is the same as the inner portion 150, except that the inner portion 350 does not include the recess 168 (see Figure 1B) used to lift the inner portion 150 above the outer portion 131 (see Figure 1E).

[0051]

[0060] The substrate support assembly 320 is identical to the substrate support assembly 120, except that the substrate support assembly 320 includes a different susceptor assembly 330, and instead of the first set of lift pins 140A and the second set of lift pins 140B described above, the substrate support assembly 320 includes only a single set of lift pins 340. The substrate support assembly 320 includes only a single set of lift pins 340 because the lift pins 340 can be used to (1) lift the substrate 50 above the susceptor assembly 330, and (2) lift the inner portion 350 of the susceptor assembly 330 above the outer portion 131 of the susceptor assembly 330.

[0052]

[0061] As shown in Figure 3A, each of the lift pin caps 365 rests on the lift pin 340 in a similar arrangement to that of the lift pin cap 165 and lift pin 140A shown in Figure 1C. Similarly, the lift pin caps 165 and lift pins 340 rest on the lift pin pad 123 in a similar arrangement to that of the lift pin cap 165, lift pin 140A, and lift pin pad 123 shown in Figure 1C. The lift pin caps 165, lift pins 340, and lift pin pad 123 can also all be positioned relative to the central axis C and the center 350C of the inner portion 350 in a similar arrangement to that described above for the lift pin cap 165, lift pin 140A, and lift pin pad 123 with reference to Figure 1C.

[0053]

[0062] Figure 3B is a side cross-sectional view showing a substrate 50 lifted above the susceptor assembly 330 by a substrate support assembly 320 according to one embodiment. A first lift pin 3401 is shown in Figure 3B. The lift pin 340 is the same as the lift pin 140A described above, except that the lift pin 340 includes a larger stop 343 (crossbar) compared to the stop 143 included in the lift pin 140A. The stop 343 has dimensions of 1 or more that are greater than the dimensions of the lower end of the hole 157. Thus, the stop 343 may be configured not to fit into the opening of the hole 157, and each lift pin 340 1-3 The stop 343 can be lifted so as to lift the inner portion 350 from the outer portion 131. Thereafter, the inner portion 350 can be removed by the robot end effector 60, for example, as shown in Figure 3C.

[0054]

[0063] Figure 3C is a side cross-sectional view showing, according to one embodiment, an inner portion 350 of a susceptor assembly 330 lifted above the outer portion 131 by a substrate support assembly 320. When the robot end effector 60 is positioned below the inner portion 350, the lift pin cap 165 can be lifted above the inner portion 350. After the robot end effector 60 is positioned below the inner portion 350, the lift pin 340 1-3 This is the lift pin cap 165 1-3 Corresponding hole 157 1-3 Lowered to be positioned back inside, the inner portion 350 of the susceptor assembly 330 can be removed from the internal space 110 of the process chamber 101 (see Figure 1A).

[0055]

[0064] The substrate support assembly 320 and the susceptor assembly 330 may allow the substrate 50 and the inner portion 350 to be removed from the process chamber at a single rotational position of the susceptor assembly 330. This simplifies the transfer of the substrate and the inner portion 350 because no separate alignment is used when the substrate rotates from one position to another to which the inner portion of the susceptor assembly is transferred.

[0056]

[0065] Another advantage of using a susceptor with a removable inner portion as described above is that the chamber cleaning process can be improved by removing the inner portion of the susceptor assembly before the cleaning process. This allows components beneath the inner portion of the susceptor assembly to be cleaned more efficiently, such as the surface of the outer portion of the susceptor assembly. In one embodiment, the lift pin cap 165 (see, for example, Figure 1D) can be lifted from the inner portion 150 of the susceptor assembly 130. This allows the surface surrounding the hole 157 to be cleaned more efficiently, for example, by an etchant gas.

[0057]

[0066] The above description applies to embodiments of the present disclosure, but other embodiments and further embodiments of the present disclosure can be devised without departing from the basic scope of the present disclosure, and the scope of the present disclosure is defined by the following claims.

Claims

1. A substrate support assembly, A susceptor assembly, An inner body, an outer rim positioned around the inner body, and an inner portion comprising a plurality of recesses, each recess being recessed relative to the lower surface of the inner body, wherein the central vertical axis of the susceptor assembly extends through the central portion of the inner body, A susceptor assembly comprising an outer portion disposed around the inner portion, the outer portion including an inner shelf, the outer rim of the inner portion being disposed on the inner shelf of the outer portion, and A substrate support assembly comprising a first plurality of lift pins, each of which lift pins is located below one of the recesses of the inner portion of the susceptor assembly.

2. The substrate support assembly according to claim 1, wherein the inner portion further comprises a plurality of holes extending from the lower surface of the inner body of the inner portion to the upper surface of the inner body of the inner portion.

3. The substrate support assembly according to claim 2, wherein the susceptor assembly further comprises a plurality of lift pin caps, each lift pin cap positioned in one of the plurality of holes.

4. The substrate support assembly according to claim 2, further comprising a second plurality of lift pins, each of the second plurality of lift pins being located below one of the holes in the inner portion of the susceptor assembly.

5. The substrate support assembly according to claim 4, wherein each of the recesses and each of the holes is located at a first distance from the center of the inner portion of the susceptor assembly.

6. The substrate support assembly according to claim 5, wherein each recess is positioned at a distance of a first angular difference from two other recesses with respect to the center of the inner portion of the susceptor assembly.

7. The substrate support assembly according to claim 6, wherein each hole is spaced from two other holes by a first angular difference with respect to the center of the inner portion of the susceptor assembly.

8. The substrate support assembly according to claim 6, further comprising a plurality of lift pin pads disposed below the first plurality of lift pins and the second plurality of lift pins, each of the plurality of lift pin pads being located at a first distance from a vertical axis extending through the center of the inner portion of the susceptor assembly.

9. The substrate support assembly according to claim 7, further comprising a plurality of lift pin pads disposed below the first plurality of lift pins and the second plurality of lift pins, each of the plurality of lift pin pads being spaced apart from two other lift pin pads by a first angular difference with respect to a vertical axis extending through the center of the inner portion of the susceptor assembly.

10. The first and second sets of lift pins are configured to rotate around the vertical axis from a first position to a second position. The first plurality of lift pins are located on the plurality of lift pin pads at the first position, The substrate support assembly according to claim 9, wherein the second plurality of lift pins are located on the plurality of lift pin pads at the second position.

11. A susceptor assembly, An inner body, an outer rim arranged around the inner body, and a plurality of recesses, each recess being recessed relative to the lower surface of the inner body, comprising an inner portion including a plurality of recesses, wherein the central vertical axis of the susceptor assembly extends through the central portion of the inner body, A susceptor assembly comprising an outer portion disposed around the inner portion, the outer portion including an inner shelf, and the outer rim of the inner portion being positioned on the inner shelf of the outer portion.

12. The susceptor assembly according to claim 11, wherein the inner portion further comprises a plurality of holes extending from the lower surface of the inner portion to the upper surface of the inner portion.

13. The susceptor assembly according to claim 12, further comprising a plurality of lift pin caps, each lift pin cap positioned in one of the plurality of holes.

14. The susceptor assembly according to claim 13, wherein each of the plurality of holes and each of the plurality of recesses are located at a first distance from the center of the inner portion.

15. The aforementioned inner portion includes the center, The plurality of recesses include a first recess positioned at a first angular position with respect to the center, a second recess positioned at a second angular position with respect to the center, and a third recess positioned at a third angular position with respect to the center. The susceptor assembly according to claim 13, wherein the angular difference between the first angular position and the second angular position is the same as the angular difference between the first angular position and the third angular position.

16. The plurality of holes include a first hole positioned at a fourth angular position with respect to the center, a second hole positioned at a fifth angular position with respect to the center, and a third hole positioned at a sixth angular position with respect to the center. The susceptor assembly according to claim 15, wherein the angular difference between the fourth angular position and the fifth angular position is the same as the angular difference between the fourth angular position and the sixth angular position.

17. The susceptor assembly according to claim 16, wherein the angular difference between the first angular position and the second angular position is the same as the angular difference between the fourth angular position and the fifth angular position.

18. A process chamber for processing substrates, The main body enclosing the internal space, An opening configured to transfer the substrate into the internal space, A process chamber comprising a susceptor assembly having an outer portion and an inner portion on the outer portion, wherein the outer portion is arranged around the inner portion, the inner portion is configured to be transported through the opening, and the central vertical axis of the susceptor assembly extends through the central portion of the inner portion.

19. The inner portion of the susceptor assembly includes an inner body and an outer rim positioned around the inner body. The process chamber according to claim 18, wherein the outer portion includes an inner shelf, and the outer rim of the inner portion is positioned on the inner shelf of the outer portion.

20. The inner portion further comprises a plurality of holes extending from the lower surface of the inner body of the inner portion to the upper surface of the inner body of the inner portion, The process chamber according to claim 19, wherein the susceptor assembly further comprises a plurality of lift pin caps, each lift pin cap positioned in one of the plurality of holes.

Images