Substrate support and processing chamber

Abstract

The present disclosure generally relates to a substrate support and a processing chamber for processing a semiconductor substrate. In one example, a substrate support has a body. The body has a top surface configured to support a substrate on the top surface. The body has a bottom surface opposite the top surface. The body has an upper portion disposed at the top surface and a lower portion disposed at the bottom surface. An IR blocking material is surrounded by the upper portion and the lower portion, where the IR blocking material is optically opaque at the IR wavelength, and the lower portion is optically transparent at the IR wavelength.

Description

Technical Field

[0001] Embodiments of the present disclosure generally relate to substrate supports and processing chambers for fabricating semiconductor devices. More specifically, the apparatus disclosed herein relates to an epitaxial deposition chamber having a susceptor. Background Art

[0002] Semiconductor substrates are processed for a variety of applications, including the fabrication of integrated devices and micro-devices. One such processing apparatus is an epitaxial processing chamber. During processing, the substrate is located on a susceptor within the epitaxial processing chamber. The susceptor is supported by a support shaft that is rotatable about a central axis. Precise control of a heating source, such as a plurality of heating lamps disposed below and above the substrate, allows the substrate to be heated within very tight tolerances. The temperature of the substrate affects the uniformity of the material deposited on the substrate.

[0003] The ability to accurately control substrate temperature within an epitaxial processing chamber has a significant impact on throughput and product yield. Conventional epitaxial processing chambers struggle to meet the temperature control standards required to manufacture next generation devices while meeting the growing demand for improved product yield and faster throughput. Currently there is no reliable method to accurately determine the temperature of a substrate during an anneal performed in an epitaxial processing chamber.

[0004] Therefore, there is a need for improved temperature control in epitaxial processing chambers. Utility Model Content

[0005] The present disclosure generally relates to a method for detecting the temperature of a substrate support and an apparatus for processing a semiconductor substrate. In one example, an apparatus for processing a semiconductor substrate is disclosed in the form of a substrate support. The substrate support has a body having a top surface configured to support a substrate on the top surface. The body has a bottom surface opposite the top surface. The body has an upper portion and a lower portion, the upper portion being disposed near and below the top surface, and the lower portion being disposed near and above the bottom surface. An IR blocking material is surrounded by the upper portion and the lower portion. The IR blocking material is optically opaque at IR wavelengths, while the lower portion is optically transparent at IR wavelengths.

[0006] In one aspect, the IR blocking material can be a dichroic reflective IR coating.

[0007] In another aspect, the IR blocking material may be formed from platinum foil.

[0008] In yet another aspect, the lower portion can be formed of quartz having a low oxygen / hydrogen content.

[0009] In another aspect, the lower portion can be optically transparent at IR wavelengths between 2.6 um and 2.7 um.

[0010] In another aspect, the upper portion can be formed of quartz having a low oxygen / hydrogen content.

[0011] In yet another aspect, the upper portion can be optically transparent at IR wavelengths between 2.6 um and 2.7 um.

[0012] In another aspect, the upper portion can be formed of dark doped quartz.

[0013] In yet another aspect, the upper portion can have an emissivity value approaching that of a black body emitter at elevated temperatures.

[0014] In another example, a semiconductor processing chamber is disclosed. The semiconductor processing chamber has a chamber body assembly. The chamber body assembly has a lower window and an upper window, wherein the lower window and the upper window surround an interior space. A plurality of temperature control elements are configured to heat the interior space. A susceptor assembly is disposed in the interior space. A lower pyrometer is disposed outside the interior chamber space and is configured to detect a first temperature of the susceptor assembly. An upper pyrometer is disposed outside the interior chamber space and is configured to detect a second temperature of the susceptor assembly. The susceptor assembly has an axis and a substrate support disposed on the axis. The substrate support has a body. The body has a top surface, and the top surface is configured to support a substrate on the top surface. The body has an IR transparent material and an IR blocking material, wherein the IR blocking material is packaged in the body and has the IR transparent material disposed below the IR blocking material, wherein the IR blocking material is optically opaque at IR wavelengths.

[0015] In another aspect, the IR transparent material may be additionally disposed over the IR blocking material.

[0016] In yet another aspect, the pedestal assembly can be configured to rotate the substrate; and one or both of the lower pyrometer and the upper pyrometer can be movable to scan the rotating substrate.

[0017] In another aspect, the processing chamber may further include a motion controller coupled to the lower pyrometer and configured to move the lower pyrometer in a manner to scan the IR blocking material.

[0018] In yet another aspect, the body may further include a dark doped quartz material disposed over the IR blocking material.

[0019] In another aspect, the dark doped quartz material can have an emissivity value approaching that of a black body emitter at elevated temperatures.

[0020] In yet another aspect, the lower pyrometer can be configured to detect IR radiation emitted from the IR blocking material. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The features of the present disclosure have been briefly summarized above and discussed in more detail below, and can be understood by referring to the embodiments of the present disclosure illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings only illustrate exemplary embodiments and are not to be construed as limiting the scope of the present disclosure, as the present disclosure may allow other equally effective embodiments.

[0022] Figure 1 is a schematic diagram of a semiconductor processing chamber having a pedestal assembly according to an embodiment of the present disclosure.

[0023] Figure 2 is a schematic diagram of a pyrometer scan of a susceptor assembly according to an embodiment of the present disclosure.

[0024] Figure 3 yes Figure 2 A schematic diagram of an example of a base assembly.

[0025] Figure 4 yes Figure 2 A schematic diagram of another example of a base assembly.

[0026] To facilitate understanding, like reference numerals have been used, where possible, to represent like elements in the figures. It is contemplated that elements and features of one embodiment may be beneficially utilized in other embodiments without further recitation. DETAILED DESCRIPTION

[0027] The present disclosure generally relates to a semiconductor processing chamber having a pedestal assembly configured to support a substrate during processing. The semiconductor processing chamber has a scanning pyrometer for accurately determining IR radiation emitted from a substrate disposed on the pedestal assembly. The pedestal assembly uses a combination of quartz and embedded infrared blocking material to form a body having a fixed emissivity at various temperatures. The fixed (i.e., constant) emissivity of the blocking material disposed in the pedestal assembly enables non-contact measurement of IR radiation (i.e., substrate temperature) to be accurately determined. Advantageously, the disclosed pedestal allows accurate temperature measurement of the substrate, resulting in improved process uniformity, better yield and throughput, faster temperature control, process optimization, and enhanced tool-to-tool process matching.

[0028] The semiconductor processing chamber is configured as a thermal deposition chamber or annealing chamber, such as an epitaxial processing chamber. However, it should be understood that other processing chambers having a pedestal, heater, electrostatic chuck or other substrate support pedestal may benefit from the disclosed pedestal assembly when accurate temperature measurement is required. For simplicity, the pedestal assembly will be described in the context of an epitaxial processing chamber. However, it should be understood that the teachings of the pedestal assembly in an epitaxial processing chamber are equally applicable to other processing chambers or systems for non-contact radiative heating.

[0029] Figure 1 1 is a schematic diagram of an epitaxial chamber 100 according to an embodiment of the present disclosure. The epitaxial chamber 100 is an epitaxial deposition chamber and can be used as part of a cluster tool (not shown). The epitaxial chamber 100 is used to grow an epitaxial film on a substrate (such as substrate 150). Alternatively, the epitaxial chamber 100 is used for etching.

[0030] The epitaxial chamber 100 includes a plurality of temperature control elements 199, a chamber body assembly 106, a susceptor assembly 124, a lower window 120, and an upper window 122. The upper window 122, the chamber body assembly 106, and the lower window 120 surround an interior space 110 of the epitaxial chamber 100. The plurality of temperature control elements 199 include a lamp module 101, an upper heater 158, a lower heater 152, and a heating gas channel 136. In addition, the plurality of temperature control elements 199 may optionally include a heating element disposed within the susceptor assembly 124. Each of the plurality of temperature control elements 199 may be used alone or in conjunction with one or more other plurality of temperature control elements 199 to control the temperature of the epitaxial chamber 100 when processing a substrate 150. The lamp module 101 includes an upper lamp module 102 and a lower lamp module 104.

[0031] The base assembly 124 is disposed in the interior space 110 and is configured to support the substrate 150 on the substrate support surface 151. The base assembly 124 is disposed between the upper lamp module 102 and the lower lamp module 104. The lower window 120 is disposed between the base assembly 124 and the lower lamp module 104. The upper window 122 is disposed between the base assembly 124 and the upper lamp module 102.

[0032] The upper lamp module 102 is disposed above the base assembly 124 and is configured to heat a substrate 150 disposed on the base assembly 124. The upper lamp module 102 includes an upper module body 126 and a plurality of lamp holes 128 disposed through the upper module body 126. Each of the plurality of lamp holes 128 includes a lamp holder 129 or a socket (in which a single lamp 130 is disposed) in the base. The orientation of the lamp 130 is generally defined by an imaginary line extending along the filament of the lamp 130 to the tip of the lamp 130. For example, a lamp 130 resting on one side of its surface has an imaginary line of the lamp 130 aligned with the filament and parallel to the surface. The orientation of the lamp 130 is also perpendicular to the chamber centerline "A", which extends vertically through the center of the upper lamp module. Alternatively, the orientation of the lamp 130 is parallel to the chamber centerline "A". Each of the lamps 130 is coupled to one of the lamp holders 129. Each of the lamp holders 129 supports one of the lamps 130 and electrically couples each of the lamps 130 to a power source (not shown). Each of the lamps 130 is fixed within the hole 128.

[0033] The upper lamp module 102 further includes a heating gas channel 136 and a pyrometer channel 138. The heating gas channel 136 is fluidly connected to the heating gas supply source 132. The heating gas channel 136 extends from the top surface to the bottom surface of the upper module body 126. The heating gas channel 136 is configured to allow a heated gas (such as heated air or heated inert gas) to flow from the heating gas supply source 132 to the top surface of the upper window 122 to convectively heat the upper window 122. Heating the upper window 122 enhances that more of the lamp 130 energy is directed to the substrate 150 instead of heating the upper window 122.

[0034] The heated gas is supplied to the upper plenum 180 defined between the upper lamp module 102 and the upper window 122 through the heated gas passage 136. The heated gas passage 136 may be disposed at the center of the upper lamp module 102. The heated gas passage 136 may have a conical shape. Alternatively, the heated gas passage 136 may have a frustoconical shape to facilitate outward flow into the upper plenum 180.

[0035] A heated gas exhaust passage 142 is also provided through the upper module body 126. The heated exhaust passage 142 is coupled to a heated exhaust pump 140. The heated exhaust pump 140 removes gas from the upper plenum 180 through the heated gas exhaust passage 142. The heated exhaust pump 140 may also be used as an exhaust pump for the processing space. In some embodiments, the heated gas exhaust passage 142 may be a groove or passage formed along an edge of the upper module body 126, or may be formed through or in a separate chamber component that is fluidly connected to the upper plenum 180.

[0036] A pyrometer passage 138 is disposed through the upper module body 126 to enable an upper pyrometer 134 (e.g., a scanning pyrometer) to measure the temperature of the substrate 150. The upper pyrometer 134 is disposed on top of the upper module body 126 and adjacent to the pyrometer passage 138. The pyrometer passage 138 extends from a top surface of the upper module body 126 to a bottom surface of the upper module body 126 adjacent to the upper window 122.

[0037] The lower lamp module 104 is disposed below the base assembly 124 and is configured to heat the bottom side of the substrate 150 when the substrate is disposed on the base assembly 124. The lower lamp module 104 includes a lower module body 182. A plurality of lamp holes 186 are disposed through the lower module body 182. Each of the plurality of lamp holes 186 has a lamp 188 disposed therein. Each lamp 188 is coupled to a lamp holder 184. Each lamp holder 184 supports a corresponding one of the lamps 188 and electrically couples the lamp 188 to a power source (not shown). The orientation of the lamp 188 is approximately perpendicular to the vertical centerline of the epitaxial chamber 100. For example, the orientation of the lamp 188 is approximately defined by an imaginary line extending through the filament to the tip of the lamp 188. The lamp 188 may be disposed in an orientation approximately perpendicular to the substrate 150. Alternatively, the orientation of the lamp 188 is parallel to the substrate 150.

[0038] The lower lamp module 104 further includes a base shaft passage 195 and a pyrometer passage 192. The base shaft passage 195 is disposed through a middle portion of the lower module body 182. A support shaft is disposed through the base shaft passage 195 and is coupled to the base assembly 124. The base shaft passage 195 is sized to allow the support shaft of the base 124 to pass through the lower module body 182.

[0039] A pyrometer passage 192 is disposed through the lower module body 182 to enable a pyrometer 190 (e.g., a scanning pyrometer) to measure the temperature of the bottom surface of the substrate 150 or the bottom surface of the substrate support. The lower pyrometer 190 is disposed below the lower module body 182, aligned with and adjacent to the pyrometer passage 192. The pyrometer passage 192 is disposed from the bottom surface of the lower module body 182 to the top surface of the lower module body 182 adjacent to the lower window 120.

[0040] The upper pyrometer 134 and the lower pyrometer 190 provide accurate readings of the IR radiation emitted from the susceptor assembly 124. The IR radiation emitted from the susceptor assembly 124 is used to accurately determine the temperature of the substrate 150.

[0041] The chamber body assembly 106 includes an injection ring 116 and a base ring 114. The injection ring 116 is disposed on top of the base ring 114. The injection ring 116 includes one or more gas injectors 108 disposed through the injection ring 116. The base ring 114 includes a substrate transfer channel 162, one or more upper chamber exhaust channels, and a lower chamber exhaust channel 164. The substrate transfer channel 162 is disposed through the base ring 114 to be opposite to the one or more upper chamber exhaust channels and the lower chamber exhaust channel 164. Each of the one or more upper chamber exhaust channels is disposed through the base ring 114 and coupled to the exhaust module. The lower chamber exhaust channel 164 is also disposed through the base ring 114.

[0042] The upper chamber 111 is a portion of the interior space 110 in which the substrate 150 is processed and the process gas is injected by the gas injector 108. The lower chamber 113 is a portion of the interior space 110 in which the substrate 150 is loaded onto the susceptor assembly 124. The upper chamber 111 can also be described as a space above the substrate support surface 151 of the susceptor assembly 124 when the susceptor assembly 124 is in the processing position. The lower chamber 113 is a space below the substrate support surface 151 of the susceptor assembly 124 when the susceptor assembly 124 is in the processing position. The processing position (not shown) is a position where the substrate 150 is flush with or above the horizontal reference plane 125. The horizontal reference plane 125 is a plane where the implant ring 116 and the base ring 114 contact each other through a plane. The horizontal reference plane 125 is perpendicular to the vertical center line of the epitaxial chamber 100.

[0043] One or more upper chamber exhaust passages and lower chamber exhaust passages 164 are coupled to one or more exhaust pumps (not shown). The one or more exhaust pumps are configured to remove exhaust gas from the interior space 110 via the one or more upper chamber exhaust passages and lower chamber exhaust passages 164. In some embodiments, each of the upper chamber exhaust passages and lower chamber exhaust passages 164 is coupled to a single exhaust pump using multiple conduits. In another embodiment, the upper chamber exhaust passage is coupled to a different exhaust pump than the lower chamber exhaust passage 164.

[0044] A substrate transfer passage 162 is formed through the base ring 114. The substrate transfer passage 162 is configured to allow a substrate to pass through the substrate transfer passage 162 from a transfer chamber of a cluster tool (not shown). A flange 168 is attached to one end of the base ring 114 to enable the epitaxial chamber 100 to be attached to a cluster tool (not shown). The substrate transfer passage 162 passes through the flange 168.

[0045] An upper cooling ring 118 and a lower cooling ring 112 are disposed on opposite sides of the chamber body assembly 106. The upper cooling ring 118 is disposed on top of the injection ring 116 and is configured to cool the injection ring 116. The lower cooling ring 112 is disposed below the base ring 114 and is configured to cool the base ring 114. The upper cooling ring 118 includes a coolant channel 146 disposed through the upper cooling ring 118. The coolant circulating through the coolant channel 146 may include water, oil, or other suitable heat transfer fluids. The lower cooling ring 112 includes a coolant channel 148 disposed through the lower cooling ring 112. The coolant circulating through the coolant channel 148 is similar to the coolant circulating through the coolant channel 146 of the upper cooling ring 118. In some embodiments, the upper cooling ring 118 and the lower cooling ring 112 help to secure the injection ring 116 and the base ring 114 in the epitaxial chamber 100. The upper cooling ring 118 may partially support the upper lamp module 102 , while the lower cooling ring 112 may partially support the base ring 114 and the implant ring 116 .

[0046] The gas injector 108 of the injection ring 116 is disposed through an opening formed through the injection ring 116. Figure 1 In the example shown, a plurality of gas injectors 108 are disposed through the injection ring 116. Each gas injector 108 is configured to supply a process gas to the interior space 110 via one or more gas outlets 178. For simplicity, Figure 1 1. A single gas injector 108 is shown. The gas injector 108 is shown as being disposed at an acute angle relative to a horizontal plane so that one or more gas outlets 178 are directed downwardly toward the susceptor 124 and the substrate 150 located below the gas injector 108. Each gas injector 108 is fluidly coupled to one or more process gas supplies, such as a first process gas supply 174 or a second process gas supply 176. In some embodiments, only the first process gas supply 174 is used. In some embodiments where both the first process gas supply 174 and the second process gas supply 176 are used, there are two gas outlets 178 within each gas injector 108. The two gas outlets 178 are formed in a single gas injector 108 and are disposed in a stacked manner so that the gases can mix only after the gases exit the gas injector 108 through the gas outlets 178 and enter the interior space 110.

[0047] The upper window 122 is disposed between the injection ring 116 and the upper lamp module 102. The upper window 122 is an optically transparent window so that the radiation generated by the upper lamp module 102 can pass through the upper window 122. In some embodiments, the upper window 122 is formed of a quartz or glass material. The upper window 122 has a dome shape and in some embodiments, is also referred to as an upper dome. The outer edge of the upper window 122 forms a peripheral support member 172. The peripheral support member 172 is thicker than the central portion of the upper window 122. The peripheral support member 172 is disposed on the top of the injection ring 116. The peripheral support member 172 is connected to the central portion of the upper window 122 and is formed of the optically transparent material of the central portion of the upper window 122.

[0048] The lower window 120 is disposed between the base ring 114 and the lower light module 104. The lower window 120 is optically transparent so that radiation generated by the lower light module 104 passes through the lower window 120. In some embodiments, the lower window 120 is formed of a quartz or glass material. The lower window 120 has a dome shape and, in some embodiments, is also referred to as a lower dome. The outer edge of the lower window 120 forms a peripheral support 170. The peripheral support 170 is thicker than the central portion of the lower window 120. The peripheral support 170 is connected to the central portion of the lower window 120 and is formed of the same optically transparent material.

[0049] Various liners and heaters are disposed within the chamber body assembly 106 and within the interior space 110. Figure 1 As shown, an upper liner 156 and a lower liner 154 are disposed within the chamber body assembly 106. The upper liner 156 is disposed above the lower liner 154 and is disposed inwardly from the injection ring 116. The lower liner 154 is disposed inwardly from the base ring 114. The upper liner 156 and the lower liner 154 are coupled together when in the processing space. The upper liner 156 and the lower liner 154 shield the inner surfaces of the injection ring 116 and the base ring 114 from the processing gas in the processing space. The upper liner 156 and the lower liner 154 are further used to reduce heat transfer from the processing space to the injection ring 116 and the base ring 114. The reduced heat transfer improves uniform heating of the substrate 150 and enables more uniform deposition on the substrate 150 during processing.

[0050] The lower chamber exhaust passage 164 is disposed across from the substrate transfer passage 162 and connects the lower chamber exhaust passage 164 to a exhaust pump (not shown). The exhaust pump may also be coupled to and in fluid communication with both of the upper chamber exhaust passage openings.

[0051] The lower liner 154 is located inside the opening of the base ring 114. The lower liner 154 has a ring shape and has a lower liner body. The lower liner 154 is configured to separate the inner surface of the base ring 114 from the inner space 110. The upper liner 156 shields the inner surface of the base ring 114 from the process gas in the inner space 110 and further protects the inner space 110 from particles or other contaminants released from the base ring 114 and the lower heater 152.

[0052] An upper heater 158 and a lower heater 152 are also disposed within the chamber body assembly 106 and the interior space 110. The upper heater 158 is disposed between the upper liner 156 and the implant ring 116, while the lower heater 152 is disposed between the lower liner 154 and the base ring 114. Both the upper heater 158 and the lower heater 152 are disposed inwardly from the chamber body assembly 106 to enable more uniform heating of the substrate 150 when the substrate 150 is within the epitaxial chamber 100. The upper heater 158 and the lower heater 152 reduce heat loss from the walls of the chamber body assembly 106 by heating the walls and preventing the walls from becoming heat sinks during processing. Thus, the upper heater 158 and the lower heater 152 produce a more uniform temperature distribution around the surfaces forming the interior space 110. Each of the upper liner 156, the lower liner 154, the upper heater 158, and the lower heater 152 is coupled to a flange 160 disposed within the interior space 110. The flange 160 is a horizontal surface that is fixed (e.g., clamped) between a portion of the injection ring 116 and the base ring 114 to fix the upper liner 156, the lower liner 154, the upper heater 158, and the lower heater 152. In the embodiments described herein, the upper heater 158 may include any suitable heater, such as a lamp, an infrared heater, a heat transfer fluid conduit, or a resistive heating element, as well as other types of heaters. The upper heater 158 is further formed to accommodate an opening through the injection ring 116 and the base ring 114. Similarly, the lower heater 152 can be configured similarly to the upper heater 158. The lower heater 152 is further formed to accommodate an opening through the injection ring 116 and the base ring 114.

[0053] The pedestal assembly 124 is disposed within the interior space 110 and is configured to support the substrate 150 during processing. The pedestal assembly 124 includes a flat upper surface and a shaft, the flat upper surface being used to support the substrate 150, the shaft extending through a portion of the lower window 120 and the lower lamp module 104. The pedestal assembly 124 is coupled to a movement assembly 194 via the shaft. The movement assembly 194 includes a rotation assembly 196 and a lifting assembly 198. The rotation assembly 196 is configured to rotate the pedestal assembly 124 around a central axis A, and the lifting assembly 198 is configured to linearly move the pedestal assembly 124 along the central axis A within the interior space 110. The central axis A is also the vertical centerline of the epitaxial chamber 100.

[0054] Figure 2 is a schematic diagram of a pyrometer scan of a pedestal assembly 124 according to an embodiment of the present disclosure. The pedestal assembly 124 includes a substrate support 200. The substrate support 200 has a top surface 201 and a bottom surface 202. One or more pyrometers are used to detect the temperature of the substrate support 200 and / or the substrate 150 disposed on the pedestal assembly 124. As described above, the epitaxial chamber 100 may have an upper pyrometer 134 disposed on, above, or in the upper lamp module 102. In one or more examples, the epitaxial chamber 100 may additionally or alternatively have a lower pyrometer 190 disposed below, in, or above the lower lamp module 104. The upper pyrometer 134 and the lower pyrometer 190 may have narrow spectral bands (e.g., IR spectral bands, such as centered between about 2.6um and about 2.7um) to avoid interference from processing equipment and improve accuracy. In one example, the upper pyrometer 134 and the lower pyrometer 190 read in a spectral band of about 2.7um.

[0055] The upper pyrometer 134 is coupled to a movement mechanism 210. The movement mechanism 210 may be a track or gimbal that moves the upper pyrometer 134 across the window 294. The window 294 is aligned with the pyrometer channel 138 of the upper module body 126. In one example, the movement mechanism 210 moves the upper pyrometer 134 in the X and Y directions relative to the window 294. In another example, the movement mechanism 210 rotationally moves the upper pyrometer 134 relative to at least one of the X and Y axes (such as a horizontal axis, where the Z axis extends in a vertical direction). The movement mechanism 210 manipulates the upper pyrometer 134 to collect IR measurements along any given upper portion / component of the substrate or epitaxial chamber 100.

[0056] As the temperature of the substrate 150 and the substrate support 200 increases, they emit energy in the form of heat. The upper pyrometer 134 detects the emitted energy in the form of IR radiation emitted from the substrate 150 or the substrate support 200 and uses the detected energy to determine the surface temperature of the substrate 150 or the substrate support 200. In order to increase the temperature that can be determined across the substrate 150 or the substrate support 200, the upper pyrometer 134 can be moved by the movement mechanism 210 to scan the entire substrate 150 and / or the substrate support 200. In other words, the movement mechanism 210 enables the upper pyrometer 134 to sample the IR radiation emitted from the substrate 150 or the substrate support 200 at multiple locations so that the temperature distribution across the surface of the substrate 150 and / or the substrate support 200 can be determined or mapped. With the movement provided by the movement mechanism 210, the upper pyrometer 134 can scan substantially the entire substrate 150 as the substrate 150 is rotated by the substrate support 200.

[0057] For example, the movement mechanism 210 is configured to move the upper pyrometer 134 radially outwardly from the center A of the epitaxial chamber 100 by a distance 282. The upper pyrometer 134 has a line of sight for detecting IR radiation emitted from the substrate 150 or the substrate support 200. The movement mechanism 210 moves the line of sight 230 of the upper pyrometer 134 by a first distance 284 to detect an area 232 on the substrate 150 and the top surface 201 of the substrate support 200. As the pedestal assembly 124 rotates, the upper pyrometer 134 is able to detect IR radiation emitted from the substrate 150 and the pedestal assembly 124 that passes through the detection area 232. In this manner, the upper pyrometer 134 can determine the temperature across the top surface 201 of the substrate support 200 and the temperature across the substrate 150. The temperatures can be recorded as a temperature map to provide a location on the substrate associated with each temperature reading.

[0058] Similar to the upper pyrometer 134, the lower pyrometer 190 is coupled to a second motion mechanism 210. The motion mechanism 210 can be a track or gimbal that moves the lower pyrometer 190 across the window 294. The window 294 is disposed in the pyrometer channel 192 of the lower module body 182. In one example, the second motion mechanism 210 moves the lower pyrometer 190 relative to the window 294 in the X and Y directions. In another example, the second motion mechanism 210 moves the lower pyrometer 190 rotationally relative to at least one of the X-axis and the Y-axis. With the motion provided by the motion mechanism 210, the lower pyrometer 190 can scan substantially the entire substrate support 200 as the substrate support 200 rotates. The motion mechanism 210 manipulates the lower pyrometer 190 to collect IR measurements along any given lower portion / component of the epitaxial chamber 100.

[0059] The lower pyrometer 190 detects emitted energy in the form of IR radiation emitted from the substrate support 200 to determine the surface temperature of the substrate support 200. To increase the temperature that can be detected across the substrate support 200, the lower pyrometer 190 can be moved by the moving mechanism 210 to scan the entire substrate support 200 as the substrate support 200 rotates.

[0060] For example, the lower pyrometer 190 may be moved radially outwardly a first distance 284 from the center A of the epitaxial chamber 100. The movement mechanism 210 moves the line of sight 290 of the upper pyrometer 134 the first distance 284 to detect an area 292 on the bottom surface 202 of the substrate support 200. As the pedestal assembly 124 rotates, the lower pyrometer 190 is able to detect IR radiation emitted from the substrate support 200 that passes through the detection area 292. In this manner, the lower pyrometer 190 can determine the temperature across the entire substrate support 200. The temperatures may be recorded as a temperature map to provide the location of each temperature reading.

[0061] The substrate support 200 is configured to enable accurate temperature readings by the upper pyrometer 134 and the lower pyrometer 190. The substrate support 200 includes an IR blocking layer surrounded by an IR transparent material. The material of the IR blocking layer is selected to provide a fixed emissivity at various temperatures so that IR radiation can be accurately read over a wide temperature range. The IR blocking layer can be a metal layer, such as a transition metal or a post transition metal. For example, the IR blocking layer can be formed of platinum. However, it should be understood that the IR blocking material can be any suitable non-metallic material that can block one wavelength or IR spectrum, such as a ceramic or a dichroic reflective IR coating. The IR transparent material of the substrate support 200 can be formed of one or more layers of quartz with a low OH (oxygen / hydrogen) content, so that the IR transparent material portion of the substrate support 200 is transparent in the IR spectrum. When the substrate support 200 is heated, the temperature of the substrate support 200 can be accurately determined by the pyrometer because the emissivity does not change with changes in temperature. Because the measured temperature from the IR blocking material in the substrate support 200 can be used to infer or calculate the substrate temperature, the substrate temperature can be accurately determined even with varying emissivity.

[0062] Figure 3 yes Figure 2Schematic diagram of a first embodiment of a substrate support 200 of the present invention. The substrate support 200 having a top surface 201 and a bottom surface 202 has a body 302 formed of an IR transmissive material. The body 302 has an upper portion 322 and a lower portion 342. The total thickness 356 of the substrate support 200 between the top surface 201 and the bottom surface 202 may be between 3 mm and about 1.5 mm, such as about 2 mm. The upper portion 322 has a lower surface 362, and the lower portion 342 has an upper surface 344. The IR transmissive material of the body 302 has an IR blocking material 310 disposed in the body 302. The IR blocking material 310 disposed in the body 302 may be in the form of a metal layer or may be other IR blocking materials. The IR blocking material 310 is spaced at least a distance 352 from the substrate supporting surface 151 (such as the top surface 201) of the body 302. The distance 352 is selected to improve manufacturability and reduce defects, and may be between about 0.3 mm and about 0.5 mm.

[0063] The IR blocking material 310 is sandwiched between the upper portion 322 and the lower portion 342 of the IR transparent material comprising the body 302. In one example, the IR blocking material 310 is completely surrounded or enclosed by the IR transparent material of the upper portion 322 and / or the lower portion 342. The upper portion 322 and the lower portion 342 may be integrally formed together to enclose the IR blocking material 310. For example, the IR blocking material 310 may be placed in the body 302 before sintering. Alternatively, the IR blocking material 310 may be 3D printed inside the body 302 while the body 302 is 3D printed. In yet another example, the IR blocking material 310 extends to the outer periphery of the substrate support 200 and separates the upper portion 322 of the body 302 from the lower portion 342 of the body 302, wherein the upper portion 322 and the lower portion 342 are discrete, separate layers.

[0064] The IR blocking material 310 is a continuous coating, film, layer or plate, so that it is continuous and has no holes or gaps, thereby enabling more accurate detection by the pyrometer. A continuous layer of the IR blocking material 310 can provide uniformity and ease of reading, but the IR blocking material 310 can also have a pattern for other reasons and interpolate emissivity data. The IR blocking material 310 is electrically insulated, that is, it is not electrically coupled to other circuits of the processing chamber directly or through a switch, so that the IR blocking material is floating. That is, the IR blocking material 310 is not part of a heater, electrode or ground, or another circuit disposed in the substrate support 200. It should be understood that the IR blocking material 310 has characteristics that enable accurate temperature measurement of the substrate support 200 by the pyrometer 124 / 190. For example, the IR blocking material 310 has a fixed emissivity at various temperatures.

[0065] IR blocking material 310 can be an embedded infrared blocking material. IR blocking material 310 can be a dichroic reflective IR coating. The thickness of IR blocking material 310 can be between about 2 microns and about 3 microns. IR blocking material 310 can be formed of platinum, stainless steel, molybdenum, aluminum, copper, their alloys, or any other suitable metal with an emissivity suitable for measuring temperature. Although IR blocking material 310 is shown as a single layer of material, there can be a second layer of IR blocking material. For example, in the case where it is necessary to read the temperature from both above and below the substrate support 200, a heater or chucking mesh can be set between the first layer of IR blocking material and the second layer of IR blocking material.

[0066] The upper portion 322 may be formed of a material having properties similar to the material forming the lower portion 342. In one example, the upper portion 322 and the lower portion 342 may be formed of the same material. The upper portion 322 and the lower portion 342 of the body 302 may be formed of a material having an emissivity that is optically transparent at IR wavelengths. In one example, the upper portion 322 and the lower portion 342 of the body 302 may be formed of synthetic quartz having a low OH content, such as synthetic quartz using chemical gas as a raw material. The chemical gas contains a silicon source that reacts with oxygen to form pure silicon dioxide. The purity that can be achieved by this manufacturing process is much higher than that of natural quartz. Electric fusion or flame fusion may be used during the manufacturing process to melt the IR transparent material. Electric fusion is the most commonly used melting process for manufacturing quartz glass. Alternatively, flame fusion does not use electric current, but uses H2 / O2-flame (H2 / O2-Flame) to heat and melt the IR transparent material. Flame fused quartz has an extremely low bubble content. In one example, the body 302 is formed of flame fused quartz. The IR transparent quartz material of the body 302 may have a thermal conductivity of approximately 0.4 7K -1 and about 10-6K -1 The IR transparent quartz material of the body 302 may have a thermal expansion of about 1.49 W·m -1 ·K -1 The IR transparent quartz material of the body 302 may have a maximum operating temperature of about 1110°C (long exposure duration) / 1250°C (short exposure duration). The IR transparent quartz material of the body 302 is extremely transparent in the IR spectrum, for example, between wavelengths of about 2.6 um and about 2.7 um, i.e., in the same range as a pyrometer.

[0067] The IR transparent quartz of the upper portion 322 and the lower portion 342 surround the IR blocking material 310. The arrangement of the transparent quartz surrounding the embedded infrared blocking material (i.e., the IR blocking material 310) provides the substrate support 200 with a fixed emissivity at various temperatures, thereby allowing accurate reading of IR radiation over a wide temperature range. For example, the body 302 is optically transparent through the lower portion 342 so that the pyrometer 190 can accurately read the emission from the IR blocking material 310 to obtain the bottom temperature of the substrate support 200, which is indicative of the temperature of the substrate 150 disposed on the body 302. Similarly, the body 302 is optically transparent through the upper portion 322 so that the pyrometer 134 can accurately read the emission from the IR blocking material 310 to obtain the top temperature of the substrate support 200. Since the substrate 150 is transparent to the pyrometer, an accurate reading of the temperature of the substrate support 200 is used to infer the temperature of the substrate 150. The substrate support 200 advantageously allows for higher temperature reading accuracy from both the top surface 201 and the bottom surface 202 of the substrate support 200 to improve substrate processing performance.

[0068] Figure 4 4 is a schematic diagram of a second embodiment of a substrate support 400. The substrate support 400 may be used to replace Figure 2 2. The substrate support 200 of FIG. 4 is similar to the substrate support 200. The substrate support 400 has a top surface 201 and a bottom surface 202. The substrate support 400 has a body 402. The body 402 is formed of an IR transparent material. The body 402 has an upper portion 422 and a lower portion 442. The body 402 additionally has an IR blocking material 310 disposed in the body 302.

[0069] The substrate support 400 may have a total thickness 456 between the top surface 201 and the bottom surface 202 between 3 mm and about 1.5 mm, such as about 2 mm. The upper portion 422 has a lower surface 462, and the lower portion 442 has an upper surface 444. The IR blocking material 310 is spaced a distance 452 from the substrate supporting surface 151 of the body 402. The distance 452 is selected to improve manufacturability and reduce defects, and may be between about 0.3 mm and about 0.5 mm.

[0070] The IR blocking material 310 is sandwiched between the upper portion 422 and the lower portion 442. In one example, the IR blocking material 310 is completely surrounded by the upper portion 422 and / or the lower portion 442. In another example, the IR blocking material 310 extends to the outer periphery of the substrate support 400 and separates the upper portion 422 of the body 402 from the lower portion 442 of the body 402. The IR blocking material 310 has a fixed (i.e., constant) emissivity at various temperatures. The IR blocking material 310 is similar to the above-described Figure 3 The description is essentially the same.

[0071] The lower portion 442 can be formed of a material having different properties than the material forming the upper portion 422. In one example, the lower portion 442 and the upper portion 422 are formed of different materials. The lower portion 442 can be formed of a material having an optically transparent emissivity. In one example, the lower portion 442 of the body 402 can be formed of synthetic quartz, such as described above with respect to the lower portion 342.

[0072] The upper portion 422 may be formed of a material having high optical absorption. For example, the upper portion 422 having a thickness as small as 3 mm may have an absorption of more than 95% over a wide wavelength range from ultraviolet to mid-wavelength infrared. In addition, at a thickness of only 1 mm, the material of the upper portion 422 provides an absorption of 80% or more over a wide wavelength range from ultraviolet to mid-wavelength infrared.

[0073] The upper portion 422 may be formed of doped quartz, silica doped quartz that is darkened to absorb IR heat faster, ceramic materials such as SiC, AlN, or other opaque high purity quartz glass composites such as silica (fused quartz) and silicon. The material of the upper portion 422 may be selected to provide high emissivity. The upper portion 422 may have an emissivity value that approaches that of a black body emitter at high temperatures. For example, the material of the upper portion 422 may emit as much or more thermal radiation energy as any other object at the same temperature. The upper portion 422 may have an emissivity of 80% or more over a wide range of wavelengths, i.e., up to 95% emissivity at wavelengths between 2.6 μm and 2.7 μm.

[0074] The material of the upper portion 422 may have a K of about 0.57×10-6 -1 The material of the upper portion 422 may have a thermal expansion of about 1.49 W·m-1·K -1 The thermal conductivity of the upper portion 422 can be about 1000°C (at 20°C). The maximum operating temperature of the material of the upper portion 422 can be about 1160°C (long exposure duration) / 1300°C (short exposure duration). The emissivity of the material of the upper portion 422 can be between about 80% and about 90% at about 1000°C. The material of the upper portion 422 advantageously provides faster heating of the substrate support 400 from the top of the processing chamber.

[0075] Advantageously, the substrate support described herein provides a constant emissivity, enabling non-contact temperature measurement of temperature-dependent substrates in the IR wavelength range. The combination of an IR transparent material surrounding an IR blocking material provides a base with a fixed emissivity at various temperatures, allowing the IR radiation emitted from the IR blocking material to be accurately read, the IR radiation being indicative of the temperature of the substrate. Thus, the substrate support is capable of accurately determining the temperature of a substrate supported on the substrate support. The rotating substrate support and the motion controlled pyrometer are also capable of scanning the IR blocking material disposed in the substrate support, such that the temperature across the entire substrate can be determined. Accurate temperature measurement of the entire substrate allows for greater processing uniformity and deposition control within processing chambers such as epitaxy chambers and annealing chambers.

[0076] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the true scope of the disclosure, the scope of which is defined by the following claims.

Claims

1. A substrate support, characterized in that: include: A subject, the subject comprising: a top surface configured to support a substrate thereon; a bottom surface, the bottom surface being opposite to the top surface; an upper portion disposed at the top surface; a lower portion disposed at the bottom surface; and An IR blocking material is surrounded by the upper portion and the lower portion, wherein the IR blocking material is optically opaque at IR wavelengths and the lower portion is optically transparent at IR wavelengths.

2. The substrate support of claim 1, wherein the IR blocking material is a dichroic reflective IR coating.

3. The substrate support of claim 1, wherein the IR blocking material is formed of platinum foil.

4. The substrate support of claim 1, wherein the lower portion is formed of quartz having a low oxygen / hydrogen content.

5. The substrate support of claim 4, wherein the lower portion is optically transparent at IR wavelengths between 2.6 um and 2.7 um.

6. The substrate support of claim 1, wherein the upper portion is formed of quartz having a low oxygen / hydrogen content.

7. The substrate support of claim 6, wherein the upper portion is optically transparent at IR wavelengths between 2.6 um and 2.7 um.

8. The substrate support of claim 1, wherein the upper portion is formed of dark doped quartz.

9. The substrate support of claim 8, wherein the upper portion has an emissivity value approaching that of a black body emitter at elevated temperatures.

10. A processing chamber, characterized in that: include: a chamber body assembly; Lower window; an upper window, wherein the lower window and the upper window are located on opposite sides of the interior chamber space; a plurality of temperature control elements configured to heat a substrate disposed in the interior space; a base assembly disposed in the interior space; and a lower pyrometer disposed outside the interior chamber space and configured to sense a first temperature of the susceptor assembly through the lower window; and an upper pyrometer disposed outside the interior chamber space and configured to detect a second temperature of the susceptor assembly through the upper window, wherein the susceptor assembly comprises: axis; A substrate support, the substrate support being disposed on the shaft, the substrate support comprising: A body having a top surface configured to support a substrate on the top surface, the body comprising: IR transparent materials; and An IR blocking material is packaged in the body and has the IR transparent material disposed below the IR blocking material, wherein the IR blocking material is optically opaque at IR wavelengths.

11. The processing chamber of claim 10, wherein the IR blocking material is a dichroic reflective IR coating.

12. The processing chamber of claim 10, wherein the IR blocking material is formed of platinum foil.

13. The processing chamber of claim 10, wherein the IR transparent material is formed of quartz having a low oxygen / hydrogen content and is optically transparent at IR wavelengths between 2.6 um and 2.7 um.

14. The processing chamber of claim 13, wherein the IR transparent material is additionally disposed over the IR blocking material.

15. The processing chamber of claim 10, wherein the pedestal assembly is configured to rotate the substrate; and one or both of the lower pyrometer and the upper pyrometer are movable to scan the rotating substrate.

16. The processing chamber of claim 10, wherein: The processing chamber further comprises: A motion controller is coupled to the lower pyrometer and configured to move the lower pyrometer in a manner that scans the IR blocking material.

17. The processing chamber of claim 10, wherein: The subject further comprises: A dark doped quartz material is disposed over the IR blocking material.

18. The processing chamber of claim 17, wherein the dark doped quartz material has an emissivity value approaching that of a black body emitter at elevated temperatures.

19. The processing chamber of claim 10, wherein the lower pyrometer is configured to detect IR radiation emitted from the IR blocking material.

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