Diode laser for wafer heating for epi process

Abstract

Embodiments of the present disclosure generally relate to apparatuses and methods for semiconductor processing, and more particularly, to thermal process chambers. A thermal process chamber can include a substrate support, a first plurality of heating elements disposed above the substrate support, and one or more high energy radiation source assemblies disposed above the first plurality of heating elements. The one or more high energy radiation source assemblies are used to provide localized heating to cold regions on a substrate disposed on the substrate support during processing. The localized heating of the substrate improves the temperature profile, which in turn improves deposition uniformity.

Description

[0001] This application is a divisional application of the invention patent application filed on October 7, 2016, with application number 201680056747.6 and invention title "Diode Laser for Wafer Heating in EPI Process". background Technical Field

[0003] Embodiments of this disclosure generally relate to apparatus and methods for semiconductor processing, and more specifically, to thermal process chambers. Background Technology

[0005] Semiconductor substrates are processed for a wide variety of applications, including the fabrication of integrated devices and microdevices. During processing, the substrate is positioned on a pedestal within a process chamber. The pedestal is supported by a support shaft that can rotate about a central axis. Precise control of the heating sources, such as multiple heating lamps positioned below and above the substrate, allows the substrate to be heated within very tight tolerances. The temperature of the substrate can affect the uniformity of the material deposited on it.

[0006] Despite precise control of substrate heating, valleys (lower deposition levels) have been observed forming at certain locations on the substrate. Therefore, there is a need for improved thermal process chambers in semiconductor processing. Summary of the Invention

[0007] Embodiments of this disclosure generally relate to apparatus and methods for semiconductor processing, and more specifically, to thermal process chambers. In one embodiment, the process chamber includes: a first arched structure; a second arched structure; a substrate support disposed between the first arched structure and the second arched structure; a first plurality of heating elements disposed above the first arched structure, wherein the first arched structure is disposed between the first plurality of heating elements and the substrate support; and a high-energy radiation source assembly disposed above the first plurality of heating elements, wherein the high-energy radiation source assembly includes a high-energy radiation source having a total output power of at least 100 W.

[0008] In another embodiment, the process chamber includes: a first arched structure; a second arched structure; a substrate support disposed between the first arched structure and the second arched structure; a first plurality of heating elements disposed above the first arched structure, wherein the first arched structure is disposed between the first plurality of heating elements and the substrate support; a support member disposed above the first plurality of heating elements, wherein the first plurality of heating elements are disposed between the first arched structure and the support member; and a first high-energy radiation source assembly disposed on the support member, wherein the high-energy radiation source assembly includes: a high-energy radiation source; and a bracket for coupling the high-energy radiation source assembly to the support member.

[0009] In another embodiment, the process chamber includes: a first arched structure; a second arched structure; a substrate support disposed between the first arched structure and the second arched structure; a plurality of heating elements disposed above the first arched structure, wherein the first arched structure is disposed between the plurality of heating elements and the substrate support; a support member disposed above the plurality of heating elements, wherein the plurality of heating elements are disposed between the first arched structure and the support member; and a high-energy radiation source assembly movably disposed on a track formed on the support member, wherein the high-energy radiation source assembly includes a high-energy radiation source. Attached Figure Description

[0010] To enable a detailed understanding of the features described above in this disclosure, a more specific description of the disclosure briefly summarized above can be obtained by referring to the embodiments (some of which are shown in the accompanying drawings). It should be understood that the drawings depict only typical embodiments of this disclosure and are not intended to limit the scope of this disclosure, as other equally effective embodiments are permissible.

[0011] Figure 1 This is a schematic cross-sectional side view of a process chamber according to one embodiment.

[0012] Figure 2 This is a schematic cross-sectional side view of a process chamber according to another embodiment.

[0013] Figure 3 This is a schematic cross-sectional side view of a process chamber according to another embodiment.

[0014] Figure 4 This is a schematic perspective view of a high-energy radiation source assembly according to the embodiments described herein.

[0015] Figure 5 According to one implementation method Figure 4 A schematic cross-sectional side view of a high-energy radiation source component.

[0016] Figure 6 This is a schematic perspective view of a high-energy radiation source assembly according to one embodiment.

[0017] Figure 7 According to one implementation method Figure 6 Enlarged schematic cross-sectional side view of a high-energy radiation source component.

[0018] Figure 8 According to one implementation method Figure 1 A schematic top view of the process chamber.

[0019] Figure 9 According to another embodiment Figure 1A schematic top view of the process chamber.

[0020] Figure 10 This illustrates the operation of a method for processing a substrate according to the embodiments described herein.

[0021] Figure 11 The display provides a data graph showing the test results for the resistivity of the substrate relative to the distance from the substrate's origin.

[0022] To facilitate understanding, the same reference numerals have been used to designate common elements in the drawings where possible. Elements disclosed in one embodiment may be advantageously used in other embodiments without specific reference. Detailed Implementation

[0023] Embodiments of this disclosure generally relate to apparatus and methods for semiconductor processing, and more specifically, to thermal process chambers. A thermal process chamber may include a substrate support, a first plurality of heating elements disposed above the substrate support, and one or more high-energy radiation source assemblies disposed above the first plurality of heating elements. The one or more high-energy radiation source assemblies are used to provide localized heating of cold regions on a substrate disposed on the substrate support during processing. Localized heating of the substrate improves the temperature profile, which in turn improves deposition uniformity.

[0024] The term "substrate" or "substrate surface" as used herein generally refers to any substrate surface on which processing is performed. For example, a substrate surface may include silicon, silicon oxide, doped silicon, silicon germanide, germanium, gallium arsenide, glass, sapphire, and any other materials such as metals, metal nitrides, metal alloys, and other conductive or semiconductor materials, depending on the application. The substrate or substrate surface may also include dielectric materials such as silicon dioxide, silicon nitride, organosilicon, and carbon-doped silicon oxide or nitride materials. The substrate itself is not limited to any particular size or shape. While the embodiments described herein are generally made with reference to a circular 200mm or 300mm substrate, other shapes (such as polygons, squares, rectangles, curves, or other non-circular workpieces) may be used according to the embodiments described herein.

[0025] Figure 1 This is a schematic cross-sectional side view of a process chamber 100 according to one embodiment. The process chamber 100 can be a process chamber for performing any thermal process, such as epitaxial processing. While a process chamber for epitaxial processes is shown and illustrated, the concepts of this disclosure are also intended to apply to other process chambers capable of providing controlled thermal cycling that heats the substrate used for processes such as, for example, thermal annealing, thermal cleaning, thermochemical vapor deposition, thermal oxidation, and thermal nitriding, regardless of whether the heating elements are disposed at the top, bottom, or both of the process chamber.

[0026] Process chamber 100 can be used to process one or more substrates, including depositing material on deposition surface 122 of substrate 110. Process chamber 100 may include a first arch structure 112, a second arch structure 114, and a substrate support 102 disposed between the first arch structure 112 and the second arch structure 114. Substrate support 102 may include a base 124 for supporting substrate 110 and a base support 126 for supporting base 124. The first arch structure 112 and the second arch structure 114 may be made of an optically transparent material (such as quartz). Substrate 110 may be brought into process chamber 100 through loading port 128 and positioned on base 124. Base 124 may be made of graphite coated with SiC. Base support 126 may be rotated by an electric motor (not shown), which in turn rotates base 124 and substrate 110.

[0027] The process chamber 100 may further include a first plurality of heating elements 106 (such as radiant heating lamps) disposed below the second arched structure 114 for heating the substrate 110 from below. The process chamber 100 may also include a second plurality of heating elements 104 (such as radiant heating lamps) disposed above the first arched structure 112 for heating the substrate 110 from above. In one embodiment, the first and second plurality of heating elements 104, 106 provide infrared radiant heat to the substrate through the first arched structure 112 and the second arched structure 114, respectively. The first and second arched structures 112, 114 may be transparent to infrared radiation, defined as transmitting at least 95% of infrared radiation.

[0028] In one embodiment, the process chamber 100 may further include one or more temperature sensors 130, such as optical pyrometers, which measure the temperature within the process chamber 100 and on the surface 122 of the substrate 110. One or more temperature sensors 130 may be disposed on a support member 132 disposed on a cover 116. A reflector 118 may be positioned outside the first arch structure 112 to reflect infrared light radiated from the substrate 110 and the first arch structure 112 back to the substrate 110. One or more high-energy radiation source assemblies 108 (such as focused high-energy radiation source assemblies, e.g., laser source assemblies) may be disposed on the support member 132. The one or more high-energy radiation source assemblies 108 may generate one or more high-energy radiation beams 134 (such as focused high-energy radiation beams, e.g., laser beams) that form beam spots on the surface 122 of the substrate 110 to perform localized heating of the substrate 110. One or more high-energy radiation beams 134 can pass through an opening 120 formed in the annular portion 136 of the reflector 118, and the first arched structure 112 can be transparent to the high-energy radiation beams (transmitting at least 95% of the radiation of the high-energy radiation beam 134). In one embodiment, one of the high-energy radiation beams 134 passes through a lens ( Figure 3 The distance D1 from which the high-energy radiation beam 134 travels to the surface 122 of the substrate 110 is approximately 400 mm, and the distance D2 from which one of the high-energy radiation beams 134 travels from the first arch structure 112 to the surface 122 of the substrate 110 is approximately 76 mm.

[0029] During operations (such as epitaxial deposition), substrate 110 can be heated to a predetermined temperature, such as less than about 750 degrees Celsius. Despite precise control of heating of substrate 110, one or more regions on substrate 110 may experience temperature nonuniformity, such as being about 2-5 degrees Celsius lower than the rest of substrate 110. Temperature nonuniformity results in film thickness nonuniformity for films deposited on the substrate in one or more regions, such as 1% or more thickness nonuniformity. To improve temperature uniformity (which in turn improves film thickness nonuniformity), one or more high-energy radiation source components 108 are used to locally heat one or more regions on substrate 110. As substrate 110 rotates during operation, local heating by one or more high-energy radiation source components 108 can be performed over an annular region at a specific radius of substrate 110. In one embodiment, the annular region has a radius of about 50 mm. In some embodiments, one or more high-energy radiation source components 108 may be movably mounted on support member 132 (such as movably mounted on a track). Figure 8On the support member 132, the track is arranged radially, and one or more high-energy radiation source assemblies 108 may be movable along the track to locally heat any cold areas on the substrate 110 during operation. In some embodiments, multiple high-energy radiation source assemblies 108 ( Figure 8 and Figure 9 It is used to simultaneously heat multiple cold areas on the substrate 110.

[0030] Figure 2 and Figure 3 A schematic cross-sectional view of a process chamber 200 according to another embodiment is shown. The process chamber 200 can be used as an epitaxial deposition chamber, a rapid thermal process chamber, or other heat treatment chamber. The process chamber 200 can be used to process one or more substrates, including depositing material on the upper surface of substrate 202, heating substrate 202, etching substrate 202, or a combination of these operations. The process chamber 200 generally includes chamber walls 103 and an array of radiant heating lamps 204 (among other components) for heating, and a base 206 disposed within the process chamber 200. Figure 2 and Figure 3 As shown, an array of radiant heating lamps 204 can be disposed below the base 206. Figure 3 As shown, an array of radiant heating lamps 204 may be positioned below and / or above the base 206. The radiant heating lamps 204 can provide a total lamp power between approximately 10 kW and approximately 60 kW. The radiant heating lamps 204 can heat the substrate 202 to a temperature between approximately 500 degrees Celsius and approximately 900 degrees Celsius. The base 206 may be a disk-like substrate support as shown, or may include an annular substrate support (not shown), which supports the substrate from its edge, exposing the back side of the substrate 202 to heat from the radiant heating lamps 204. The base 206 may be formed of silicon carbide or graphite coated with silicon carbide to absorb radiant energy from the lamps 204 and conduct the radiant energy to the substrate 202, thereby heating the substrate 202.

[0031] The base 206 is located within the process chamber 200, between a first transmission member 208 (which may be an arched structure) and a second transmission member 210 (which may also be an arched structure). The first transmission member 208 and the second transmission member 210, together with a base ring 212 disposed between the first transmission member 208 and the second transmission member 210, generally define an internal region 211 of the process chamber 200. Each of the first transmission member 208 and / or the second transmission member 210 may be convex and / or concave. In some embodiments, each of the first transmission member 208 and / or the second transmission member 210 may be transparent. The first transmission member 208 may be disposed between the chamber wall 103 and the base 206. In some embodiments, an array of radiant heating lamps 204 may be disposed outside the internal region 211 of the process chamber 200 and / or above the first transmission member 208, for example, defining a region 149 between the first transmission member 208 and the reflector 254 (described below). The substrate 202 can be transferred into the process chamber 200 and positioned on the base 206 through a loading port (not shown) formed in the base ring 212. A process gas inlet 214 and a gas outlet 216 may be provided in the base ring 212.

[0032] The base 206 includes a shaft or rod 218 coupled to the motion assembly 220. The motion assembly 220 includes one or more actuators and / or adjustment devices that provide movement and / or adjustment of the rod 218 and / or the base 206 within the internal region 211. For example, the motion assembly 220 may include a rotary actuator 222 that rotates the base 206 about a longitudinal axis A of the process chamber 200. The longitudinal axis A may include the center of the XY plane of the process chamber 200. The motion assembly 220 may include a vertical actuator 224 to raise and lower the base 206 in the Z direction. The motion assembly 220 may include a tilt adjustment device 226 for adjusting the planar orientation of the base 206 in the internal region 211. The motion assembly 220 may also include a lateral adjustment device 228 for left-right adjustment of the positioning of the rod 218 and / or the base 206 within the internal region 211. In embodiments including a lateral adjustment device 228 and a tilt adjustment device 226, the lateral adjustment device 228 is used to adjust the positioning of the rod 218 and / or the base 206 in the X and / or Y directions, while the tilt adjustment device 226 adjusts the angular orientation (α) of the rod 218 and / or the base 206. In one embodiment, the motion assembly 220 includes a pivoting mechanism 230. When the second transmission member 210 is attached to the process chamber 200 via the base ring 212, the pivoting mechanism 230 allows the motion assembly 220 to move the rod 218 and / or the base 206 at least in angular orientation (α) to reduce stress on the second transmission member 210.

[0033] The base 206 is shown in an elevated processing position, but can be raised or lowered vertically by the motion assembly 220 as described above. The base 206 can be lowered to a transfer position (below the processing position) to allow the lifting rod 232 to contact the second transmission member 210. The lifting rod 232 extends through a hole 207 in the base 206 as the base 206 descends, and the lifting rod 232 raises the substrate 202 from the base 206. A robot (not shown) can then enter the process chamber 200 to engage and remove the substrate from the process chamber 200 via a loading port. A new substrate 202 can be loaded onto the lifting rod 232 by the robot, and the base 206 can then be actuated upwards to a processing position to place the substrate 202 with its device side 250 facing upwards. The lifting rod 232 includes an enlarged head, allowing the lifting rod 232 to be suspended in the opening by the base 206 in the processing position. In one embodiment, a support 234 coupled to the second transmission member 210 provides a flat surface for contact with the lifting rod 232. The support provides one or more surfaces parallel to the XY plane of the process chamber 200 and serves to prevent binding of the lifting rod 232 that could occur if the end of the lifting rod were allowed to contact the curved surface of the second transmission member 210. The support 234 may be made of an optically transparent material such as quartz to allow energy from the lamp 204 to pass through it.

[0034] The base 206 (when positioned in the processing orientation) divides the interior space of the process chamber 200 into a process gas region 236 above the base 206 and a purge gas region 238 below the base 206. The base 206 is rotated during processing by a rotary actuator 222 to minimize the effects of heat and spatial anomalies in the process chamber 200, and thus promote uniform processing of the substrate 202. The base 206 can rotate between approximately 5 RPM and approximately 100 RPM, for example, between approximately 10 RPM and approximately 50 RPM. The base 206 is supported by a rod 218, which is typically aligned with the center of the base 206 and facilitates movement of the base 206 and the substrate 202 in the vertical direction (Z-direction) during substrate transport and, in some cases, during substrate processing.

[0035] Generally, the central portion of the first transmission member 208 and the bottom of the second transmission member 210 are formed of an optically transparent material such as quartz. The thickness and curvature of the first transmission member 208 can be selected to provide a flatter geometry for uniform flow in the process chamber.

[0036] One or more lamps (such as an array of radiant heating lamps 204) may be positioned adjacent to and below the second transmission member 210 in a specific manner around the rod 218. The radiant heating lamps 204 may be independently controlled in the regions to control the temperature of individual regions of the substrate 202 as process gases pass over them, thereby facilitating material deposition onto the upper surface of the substrate 202. Although not discussed in detail here, the deposited material may include silicon, doped silicon, germanium, doped germanium, germanium silicide, gallium arsenide, gallium nitride, or aluminum gallium nitride.

[0037] Radiant heating lamps 204 may include a radiant heat source (described herein as bulbs 241) and may be configured to heat substrate 202 to a temperature ranging from about 200 degrees Celsius to about 1600 degrees Celsius. Each bulb 241 may be coupled to a power distribution board, such as a printed circuit board (PCB) 252, through which power is supplied to each bulb 241. If needed, supports may be used to couple the bulbs 241 to the power distribution board to change the lamp arrangement. In one embodiment, the radiant heating lamps 204 are located within lamp holders 245, which may be cooled during or after processing by, for example, introducing cooling fluid into channels 249 located between the radiant heating lamps 204.

[0038] A circular shield 246 may optionally be disposed around the base 206 and coupled to the sidewall of the chamber body 248. The shield 246 prevents or minimizes leakage of heat / optical noise from the lamp 204 to the device side 250 of the substrate 202, while providing a preheating zone for process gases. The shield 246 may be made of CVD SiC, SiC-coated sintered graphite, grown SiC, opaque quartz, coated quartz, or any similar suitable material resistant to chemical decomposition caused by process and purge gases. In some embodiments, the shield 246 is coupled to a gasket 263 disposed on the base ring 212.

[0039] The substrate temperature is measured by a sensor configured to measure the temperature at the bottom of the base 206. The sensor may be a pyrometer (not shown) disposed in an opening formed in the lamp holder 245. Alternatively, one or more sensors 253 (such as pyrometers) may be directed to measure the temperature of the device side 250 of the substrate 202. A reflector 254 may optionally be positioned outside the first transmission member 208 to reflect infrared light radiated from the substrate 202 and redirect energy back onto the substrate 202. The reflector 254 may be secured to the first transmission member 208 using a clamp 256. The reflector 254 may be disposed adjacent to the chamber wall 103. In some embodiments, the reflector may be coupled to the chamber wall 103. The reflector 254 may be made of a metal such as aluminum or stainless steel. The sensor 253 may be configured to receive radiation from the device side 250 of the substrate 202 through the reflector 254.

[0040] Process gas supplied by process gas supply source 251 is introduced into process gas region 236 through process gas inlet 214 formed in the sidewall of base ring 212. Process gas inlet 214 is configured to guide the process gas in a generally radially inward direction. Thus, in some embodiments, process gas inlet 214 may be a cross-flow gas injector. The cross-flow gas injector is positioned to guide the process gas across the surface of base 206 and / or substrate 202. During the film formation process, base 206 is positioned in a processing orientation adjacent to and at approximately the same height as process gas inlet 214, thus allowing the process gas to flow generally along flow path 273 across the upper surface of base 206 and / or substrate 202. Process gas exits process gas region 236 (along flow path 275) through gas outlet 216 located on the opposite side of process chamber 200 as process gas inlet 214. The removal of process gas through gas outlet 216 can be facilitated by a vacuum pump 257 coupled to gas outlet 216.

[0041] Purified gas supplied by purge gas source 262 is introduced into purge gas region 238 through purge gas inlet 264 formed in the sidewall of base ring 212. Purge gas inlet 264 is located at a height below process gas inlet 214. If a circular shield 246 is used, the circular shield 246 may be located between process gas inlet 214 and purge gas inlet 264. In either case, purge gas inlet 264 is configured to guide purge gas in a generally radially inward direction. Purge gas inlet 264 may be configured to guide purge gas in an upward direction. During the membrane formation process, base 206 is positioned such that purge gas flows generally along flow path 265 across the back side of base 206. Purge gas leaves purge gas region 238 (along flow path 266) and exits the process chamber 200 through gas outlet 216 located on the opposite side of process chamber 200 as purge gas inlet 214.

[0042] The process chamber 200 further includes a high-energy radiation source assembly 270, such as a focused high-energy radiation source assembly, for example, a laser system assembly. The high-energy radiation source assembly 270 may be coupled to the process chamber 200. In some embodiments, the process chamber 200 may include a plurality of high-energy radiation source assemblies 270, for example, two or more assemblies 270 coupled to the process chamber 200.

[0043] Figure 4 schematically shown Figure 2 and Figure 3 A perspective view of a high-energy radiation source assembly 270. The high-energy radiation source assembly 270 includes a source 272, a source 274, and a fiber cable 276. The source 274 is operatively connected to the source 272 via the fiber cable 276. In some embodiments, the high-energy radiation source assembly 270 may be a laser system assembly, such as a diode laser system assembly. The fiber cable 276 may include at least one diode. In some embodiments, the fiber cable 276 may include multiple diodes. Furthermore, in some embodiments, the high-energy radiation source assembly 270 may include multiple sources 272 operatively connected to the source 274. The multiple sources 272 may be operatively connected to the source 274 via one or more fiber cables 276. In some embodiments, the source 272 may be coupled to a process chamber 200 and adjacent to an on-lamp module (e.g., Figure 2 (as shown in the diagram), and / or adjacent to the lifting rod 232. The source 272 can fix the end of the fiber optic cable 276 in a fixed position, so that the orientation of the high-energy radiation beam (such as a laser beam) is controlled.

[0044] The high-energy radiation source assembly 270 may further include a mounting bracket 278. The mounting bracket 278 may be coupled to the process chamber 200. The source 272 may be coupled to the mounting bracket 278. The high-energy radiation source assembly 270 may further include a cover plate 280, a reflector 254, and a reflector member 284.

[0045] Reflector 254 may be coupled to chamber wall 103 and / or mounting bracket 278. In some embodiments, reflector 254 may be a disk; however, reflector 254 is conceivable to be any suitable shape. Reflector member 284 may be circular. Reflector member 284 may have an outer wall 294, a first edge 295, and a second edge 296. The outer wall 294, the first edge 295, and / or the second edge 296 may be circular, annular, or other suitable shapes. The first edge 295 may be located at a first end 297 of reflector member 284, and the second edge 296 may be located at a second end 298 of reflector member 284, wherein the first edge and the second edge 296 are opposite each other. The first edge 295 and the second edge 296 may be substantially perpendicular to the outer wall 294. The second edge 296 may include at least one hole 199 drilled through the second edge 296 to allow light to pass through reflector member 284. Source 272 can be positioned such that light from source 272 enters through aperture 199 toward substrate 202 and / or base 206. Reflector member 284 can be coupled to reflector 254. In some embodiments, reflector member 284 can be coupled to a first edge 295 of reflector member. In some embodiments, reflector member 284 can be coupled to reflector member 284 via screw connection, bolt connection and / or any other suitable connecting member.

[0046] The cover plate 280 can be circular or disc-shaped; however, it is conceivable that the cover plate 280 can be any suitable shape. The cover plate 280 may have a diameter smaller than the diameter of the reflector 254. The cover plate 280 may be disposed between the mounting bracket 278 and the reflector 254. The cover plate 280 may be coupled to the reflector 254. In some embodiments, the cover plate 280 may be bolted, screwed, and / or any other suitable connection mechanism coupled to the reflector 254.

[0047] The high-energy radiation source assembly 270 is positioned to guide a high-energy radiation beam between approximately 90 mm and approximately 130 mm from the central region C of the base 206, for example, in the region of the base 206 between approximately 100 mm and approximately 120 mm.

[0048] Figure 5 schematically shown Figure 4An enlarged view of the high-energy radiation source assembly 270. As shown, the mounting bracket 278 is coupled to the cover plate 280. In some embodiments, the mounting bracket 278 may be coupled to the cover plate 280 via a bolt mechanism. Figure 5 As shown, mounting bracket 278 is coupled from its bottom side to cover plate 280 via fastening mechanism 504, which may include bolts. In some embodiments, mounting bracket 278 may be a "C"-shaped mounting bracket 278 or an "L"-shaped mounting bracket 278; however, it is conceivable that mounting bracket 278 may be any suitable shape. Mounting bracket 278 may include a first arm 286 extending parallel to the surface of cover plate 280 and / or a second arm 288 extending perpendicular to the surface of cover plate 280. Source 272 may be coupled to mounting bracket 278. In some embodiments, source 272 may be coupled to the first arm 286 of mounting bracket 278 such that source 272 is raised relative to cover plate 280.

[0049] The first arm 286 of the mounting bracket 278 (in some embodiments, coupled to the source 272) may be tilted such that the first arm 286 and the second arm 288 of the mounting bracket 278 are not perpendicular. The first arm 286 of the mounting bracket 278 may be tilted relative to the surface 282 of the cover plate 280 at an angle between approximately -4 degrees and approximately 4 degrees. For example, in some embodiments, the source 272 may be tilted by 2 degrees relative to the surface 282 of the cover plate 280 and / or the surface of the base 206. The surface 282 of the cover plate 280 may be parallel to the horizontal axis D of the base 206. In some embodiments, the first arm 286 of the mounting bracket 278 has a first central axis A, and the second arm 288 of the mounting bracket 278 has a second central axis B. The first central axis A is not orthogonal to the second central axis B. Furthermore, in some embodiments, the base 206 has a horizontal axis D. The first central axis A of the first arm 286 of the mounting bracket 278 is not parallel to the horizontal axis D of the base 206.

[0050] In some embodiments, mounting bracket 278 may include a third arm 189. The third arm 189 of mounting bracket 278 may have a central axis E. The central axis E of the third arm 189 may be parallel to the surface 282 of cover plate 280. The third arm 189 may be coupled to cover plate 280. In some embodiments, the third arm 189 may be coupled to cover plate 280 by bolting and / or any other suitable connection mechanism. The second arm 288 of mounting bracket 278 may be tilted such that the central axis B of the second arm 288 is not perpendicular to the central axis E of the third arm 189. In some embodiments, the central axis B of the second arm 288 may be tilted between approximately -4 degrees and approximately 4 degrees from an axis perpendicular to the central axis E of the third arm 189. The central axis A of the first arm 286 may be perpendicular to the central axis B of the second arm.

[0051] The tilting of the first arm 286 of the mounting bracket 278 and the source 272 reduces and / or prevents backshot of light to the laser head 272. Furthermore, the tilting of the source 272 positions the high-energy radiation source assembly 270 to guide light to a region of the base 206 between approximately 90 mm and approximately 130 mm from the central region C of the base 206, for example, between approximately 100 mm and approximately 120 mm. The positioning of the high-energy radiation source assembly 270 and the guiding of light to a region of the base 206 between approximately 90 mm and approximately 130 mm from the central region C of the base 206 directs light onto the region of the base 206 and / or the substrate 202 coupled to at least one lifting rod 232.

[0052] The high-energy radiation source assembly 270 may further include a lens holder 290. The lens holder 290 may be coupled to a mounting bracket 278. In some embodiments, the lens holder 290 may be coupled to a second arm 288 of the mounting bracket 278. The lens holder 290 may be coupled to the mounting bracket 278 by bolting, screwing, and / or any other suitable connection mechanism. For example, as... Figure 5 As shown, lens holder 290 is coupled to mounting bracket 278 by screw 502. Lens holder 290 extends outward from mounting bracket 278 such that it is positioned between source 272 and cover plate 280. Lens holder 290 can be tilted at the same angle or a substantially similar angle to the tilt angle of source 272. Therefore, the central axis F of lens holder 290 can be substantially parallel to the central axis G of source 272.

[0053] Lens holder 290 may include lens 292. Lens 292 may be a telecentric lens. Telecentric lens 292 may defocus light from laser head 272 into a beam. In some embodiments, telecentric lens 292 may collimate light. In some embodiments, if light has a focal point when incident on telecentric lens 292, the light may leave telecentric lens 292 without a focal point or with a focal point at infinity. In some embodiments, lens 292 may focus light from source 272 into a beam having a diameter between about 2 mm and about 10 mm, for example, between about 4 mm and about 8 mm. In some embodiments, lens holder 290 may include one or more optical elements.

[0054] Source 274 can be offsite or onsite. The source can generate energy, such as light. In some embodiments, source 274 can be a diode laser source. The diode can be electrically pumped. The recombination of electrons and holes generated by the applied current can introduce optical gain. Reflection from the ends of the crystal can form an optical resonator, although the resonator can be external. In some embodiments, source 274 can be a fiber laser source. The fiber laser source can be a solid-state laser or a laser amplifier, where light is guided by total internal reflection in a single-mode fiber. This light guidance allows for a long gain region. Furthermore, the waveguide properties of the fiber laser reduce thermal distortion of the beam. Erbium and / or ytterbium ions can be the active material in the fiber laser. Source 274 can provide laser power between about 20 watts and about 200 watts.

[0055] In some embodiments, source 274 may be a source of laser light. Therefore, in some embodiments, fiber optic cable 276 may be an optical tube that transmits laser light into process chamber 200. Alternatively, in some embodiments, fiber optic cable 276 may be a single-pass amplifier.

[0056] In some embodiments, source 274 may be a source of seed photons. Therefore, in some embodiments, fiber optic cable 276 is a laser medium containing at least one diode. In some embodiments, the diode may be located inside fiber optic cable 276. Fiber optic cable 276 may be an oscillator. Therefore, source 274 is a source of seed photons configured to initiate stimulated emission of photons in fiber optic cable 276 or other such laser media. Source 274 and fiber optic cable 276 together may contain a laser.

[0057] As described above, during the processing of a new substrate 202 within the process chamber 200, the substrate 202 can be loaded onto the lifting rod 232 by a robotic arm, and the base 206 can then be actuated upwards to a processing position to place the substrate 202 with its device side 250 facing upwards. The lifting rod 232 includes an enlarged head, allowing the lifting rod 232 to be suspended in an opening by the base 206 in the processing position. The high-energy radiation source assembly 270 can provide localized heating to eliminate cold spots caused by the lifting rod 232. Thus, the high-energy radiation source assembly 270 can focus a beam of light between about 2 mm and about 20 mm, for example, about 10 mm. In some embodiments, the high-energy radiation source assembly 270 can focus the beam as the substrate 202 rotates within the process chamber 200. Heating from the laser beam can cause a reduction in the resistivity (Rs) profile of the implanted substrate 202 during annealing, as the increase in temperature reduces the resistivity.

[0058] To locally heat and / or adjust specific areas of the substrate, such as those coupled to and / or near the lifting rod 232, the high-energy radiation source assembly 270 can be guided to the appropriate position and operated at specific times. In some embodiments, by way of example only, the lifting rod 232 operates at approximately 32 RPM and moves at a speed of approximately 380 mm / s. To achieve an accuracy of less than 1 mm, the timing control is calculated to be less than approximately 2.5 ms. In some embodiments, light focusing can be performed at specific time intervals. In other embodiments, a shutter with a speed similar to that of the base 206 can be used as needed. In some embodiments, a laser with a raisetime of 6 microseconds can be used.

[0059] In some embodiments, the high-energy radiation source assembly 270 can provide a pulsed beam of light, such that the high-energy radiation source assembly 270 is turned on and operated for 0.5 ms before the lifting rod 232 contacts the substrate 202. Other time intervals are conceivable. In some embodiments, the high-energy radiation source assembly 270 may be turned off for 0.5 ms after the substrate has passed through the light from the high-energy radiation source assembly 270.

[0060] It is further conceivable that multiple high-energy radiation source assemblies 270 can be used within the process chamber 200. Furthermore, in some embodiments, a source 272 on a movable track can be used to ensure proper adjustment of the substrate 202. The movable track allows the source 272 to sweep across the substrate 202, thus allowing for coarse adjustments with a predetermined pattern. In such embodiments, the source 272 can move radially inward from the outer circumference. However, in other embodiments, the source 272 can move radially outward, such as from the origin of the substrate.

[0061] In order to trigger the high-energy radiation source assembly 270 at the appropriate time (i.e., when the substrate 202 passes through an acceptable position), the high-energy radiation source assembly 270 is activated when the lifting rod 232 is approximately aligned with and / or at the focusing orientation. Therefore, the movement of the lifting rod 232 is synchronized with the high-energy radiation source assembly 270.

[0062] In one embodiment, a mark may be constructed on the base 206 to indicate the position of the lifting rod 232. The mark may have a width between about 0.1 degrees and about 1.0 degrees. The mark may be machined and / or mounted to or coupled to the base 206. In some embodiments, a delay may be introduced in the mark signal to mitigate mounting or coupling tolerances. The delay may be adjusted to improve the accuracy of the high-energy radiation source assembly 270, and thus improve the accuracy of the light associated with the position of the lifting rod 232.

[0063] In some embodiments, the marker may be a homing flag and / or an optical sensor. The marker may trigger an optical switch associated with a homing position on substrate 202. In some embodiments, the marker may be machined into or coupled to a rotating component, such as a base.

[0064] In another embodiment, a rotary encoder may be used to synchronize the high-energy radiation source assembly 270. In some embodiments, the encoder may be a range-based encoder. The encoder may be controlled by the controller 250 described below. The encoder may have a resolution of about 0.03 degrees or better to achieve an accuracy of less than 1 mm and may be pulled in less than (in some embodiments, for example) 2.5 ms. In other embodiments, the encoder may be pulled at a rate of 1 ms.

[0065] In another embodiment, the imaging process can be used to detect features on the base 206 and predict when to excite the high-energy radiation source component 270. The imaging process can be completed in a turnaround time of less than 2.5 ms. Therefore, an algorithm can be determined and controlled by the controller 250 to predict and / or determine when to excite the high-energy radiation source component 270.

[0066] The process chamber 200 described above can be accessed via a processor-based system controller (such as in...). Figure 2 and Figure 3 The controller 250 shown is used for control. For example, the controller 250 may be configured to control the flow of various precursors, process gases, and purge gases from a gas source during different operations in a substrate process sequence. By further example, the controller 250 may be configured to control the excitation of a high-energy radiation source assembly 270, predict algorithms for exciting the high-energy radiation source assembly 270, control the operation of markers and / or marker signals, and / or encode or synchronize the high-energy radiation source assembly 270, as well as the operation of other controllers. The controller 250 includes a programmable central processing unit (CPU) 252 that can operate with a memory 255 and a mass storage device, an input control unit and a display unit (not shown) (such as a power supply, clock, cache, input / output (I / O) circuitry, etc.), and various other components coupled to the process chamber 200 to facilitate control of the substrate processing. The controller 250 also includes hardware for monitoring the substrate processing via sensors in the process chamber 200, including sensors for monitoring the flow rates of precursors, process gases, and purge gases. Other sensors that measure system parameters (such as substrate temperature, chamber ambient pressure, etc.) can also provide information to the controller 250.

[0067] To facilitate control of the process chamber 200 described above, CPU 252 can be one of any form of general-purpose computer processor (such as a programmable logic controller (PLC)) usable in an industrial environment for controlling various chambers and subprocessors. Memory 255 is coupled to CPU 252 and is non-transitory, and can be one or more readily available memories, such as random access memory (RAM), read-only memory (ROM), floppy disk drive, hard disk, or any other form of digital storage (local or remote). Support circuitry 257 is coupled to CPU 252 for supporting the processor in a conventional manner. The generation of charged species, heating, and other processes are typically stored in memory 255, typically as software routines. Software routines can also be stored and / or executed by a second CPU (not shown) located at a hardware remotely controlled by CPU 252.

[0068] Memory 255 is in the form of a computer-readable storage medium containing instructions that, when executed by CPU 252, facilitate the operation of process chamber 200. The instructions in memory 255 are in the form of a program product, such as a program implementing the methods of this disclosure. The program code may conform to any of the different programming languages. In one example, this disclosure may be implemented as a program product stored on a computer-readable storage medium for use with a computer system. The program(s) of the program product define the functionality of the implementation (including the methods described herein). Exemplary computer-readable storage media include, but are not limited to: (i) non-writable storage media (e.g., read-only memory devices within a computer, such as CD-ROM discs readable by a CD-ROM drive, flash memory, ROM chips, or any type of solid-state non-transitory semiconductor memory), on which information is permanently stored; and (ii) writable storage media (e.g., floppy disks or hard disk drives within a floppy disk drive, or any type of solid-state random access semiconductor memory), on which changeable information is stored. Such a computer-readable storage medium is an embodiment of this disclosure when it carries computer-readable instructions that direct the function of the methods described herein.

[0069] Figure 6 It is a high-energy radiation source component 108 according to one embodiment. Figure 1 A perspective view of (e.g.) Figure 6As shown, a high-energy radiation source assembly 108 of one or more components 108 may include a high-energy radiation source 602 and a support 610 for supporting components of the high-energy radiation source assembly 108. The high-energy radiation source assembly 108 may further include a cage plate 608 disposed on the support 610 for securing a fiber connector 606. In one embodiment, the high-energy radiation source 602 is connected to the fiber connector 606 via a fiber 604. The high-energy radiation source 602 may be used to enable the substrate 110 ( Figure 1 Any suitable high-energy radiation source that generates radiant energy (such as focused radiant energy) by increasing the power of the radiation source by 2-5 degrees Celsius. The focused high energy may have a wavelength in the visible range. In one embodiment, the high-energy radiation source 602 is a laser source comprising two laser diodes, each having an output power of at least 50 W, for a total output power of at least 100 W and a wavelength of approximately 810 nm. In one embodiment, the high-energy radiation source 602 is a vertical-cavity surface-emitting laser (VCSEL) comprising 33 chips in series, having a total output power of 264 W (8 W output power per chip). The fiber 604 may be approximately 15 m in length. In one embodiment, instead of coupling the high-energy radiation beam to the fiber 604, the high-energy radiation source 602 is mounted on a support 610.

[0070] The high-energy radiation source assembly 108 may further include an optical retainer 612 for holding one or more lenses (such as aspherical lenses). Figure 7 The high-energy radiation source assembly 108 may be mounted on a support block 614 bolted to the support member 132. Alternatively, the high-energy radiation source assembly 108 may be mounted on a track along the radial direction of the substrate 110. Figure 8 ).

[0071] Figure 7 This is an enlarged schematic cross-sectional side view of a high-energy radiation source assembly 108 according to one embodiment. Figure 7As shown, cage plate 608 may include two retaining rings 708, 710 for securing fiber connector 606. Optical retainer 612 may include retaining ring 712 for securing lens 714 (such as an aspherical lens). Support 610 may include a first portion 702 coupled to support block 614, a second portion 704 at an angle A relative to the first portion 702, and a third portion 706 at an angle B relative to the second portion 704. Optical retainer 612 may be coupled to the second portion 704, and cage plate 608 may be coupled to the third portion 706. In one embodiment, angle B is approximately 90 degrees, and angle A is an acute or obtuse angle other than 90 degrees, such that the second portion 704 is not substantially perpendicular to surface 122 of substrate 110. Figure 1 In one embodiment, angle A is approximately 92 degrees and angle B is approximately 90 degrees, such that lens 714 is tilted 2° relative to the third portion 706 to prevent potentially damaging reflections of the high-energy radiation source 602 back into fiber 604. Alternatively, angle A is approximately 90 degrees and angle B is an acute or obtuse angle other than 90 degrees. The acute or obtuse angle A or B can be used to determine the position of the beam spot of one or more high-energy radiation beams 134 on substrate 110. In one embodiment, the first, second, and third portions 702, 704, 706 are made of a single piece of material, and angles A and B are set and non-adjustable. In another embodiment, the first, second, and third portions 702, 704, 706 are made of different pieces of material, and angles A and B are adjustable.

[0072] In one embodiment, the high-energy radiation beam exiting fiber 604 (such as a focused high-energy radiation beam, e.g., a laser beam) has a diameter of approximately 800 micrometers, which is re-imaged onto substrate 110 by lens 714 at a magnification of 17x, such that the beam spot on substrate 110 has a diameter of approximately 10 mm. In one embodiment, the laser beam exiting the fiber diverges with approximately 0.17 NA. A focused high-energy radiation beam 134 of one or more high-energy radiation beams 134 travels a distance D3 from fiber connector 606 to lens 714 of approximately 18 mm. The first arched structure 112 ( Figure 1 The transparent material can cause a slight displacement of the beam spot on the substrate, which can be compensated for by adjusting angle A or B. A small percentage of the high-energy radiation beam can be reflected by the first arch structure 112. In one embodiment, approximately 7W of power is reflected by the first arch structure, while the total output power of the high-energy radiation beam 134 is approximately 90W.

[0073] Figure 8 According to one implementation method Figure 1 A schematic top view of the process chamber 100. (See attached image.) Figure 8As shown, the process chamber 100 includes one or more temperature sensors 130 supported by a support member 132. A track 802 may be formed radially on the support member 132, and one or more high-energy radiation source assemblies 108 may be movably disposed on the track 802. The one or more high-energy radiation source assemblies 108 may be moved during or between processes to provide localized heating of various regions on the substrate 110. Figure 8 As shown, there are two high-energy radiation source assemblies 108 disposed on track 802 for simultaneously heating cold regions on substrate 110. In some embodiments, one high-energy radiation source assembly 108 is disposed on track 802. In some embodiments, more than two high-energy radiation source assemblies 108 are disposed on track 802.

[0074] Figure 9 According to one implementation method Figure 1 A schematic top view of the process chamber 100. (See attached image.) Figure 9 As shown, a high-energy radiation source assembly 108 is disposed on support block 614, and a second high-energy radiation source assembly 108 is disposed on support block 902. Support blocks 614 and 902 may be disposed at different radial positions on support member 132 to simultaneously heat different radial regions of substrate 110. Again, in some embodiments, one high-energy radiation source assembly 108 is used, while in other embodiments, more than two high-energy radiation source assemblies 108 are used.

[0075] Figure 10 The operation of a method 1000 for processing a substrate is illustrated schematically. In some embodiments, method 1000 may involve locally heating the substrate within an epitaxial deposition chamber.

[0076] At operation 1010, the substrate is placed on the base of the process chamber. In some embodiments, the process chamber may be an epitaxial deposition chamber. The process chamber may be process chamber 100 or process chamber 200. At operation 1020, the substrate is rotated.

[0077] At operation 1030, the rotational orientation of the substrate is detected. The rotational orientation of the substrate can be received by a controller and / or a sensor, which can be a camera or equivalent, or a thermal sensor. The rotational orientation can indicate the position and / or positioning of the substrate and / or the position and / or positioning of the base within the processing chamber. The rotational orientation can also indicate the speed and / or timing of the substrate and / or the base within the processing chamber.

[0078] At operation 1040, when the substrate's rotational orientation reaches a first target orientation, a high-energy source (such as a laser source) is excited. The laser source can be a diode laser source. The high-energy source is coupled to a first position between approximately 100 mm and approximately 120 mm from the center region of the substrate within the process chamber. Laser excitation can be caused by the diode laser source. Laser excitation can last for any duration and, in some embodiments, can be continuous excitation and / or pulsed excitation. Laser excitation can heat a region, part, or specific area of ​​the substrate, as described above. Furthermore, exciting the diode laser source can redirect the light from the diode laser source to a first region of the chamber, thus allowing the light from the laser source to modulate and / or heat the first region. In some embodiments, the first region of the chamber may include a region of the substrate coupled to a lifting rod of the chamber. Therefore, the light can modulate and / or heat the region of the substrate coupled to the lifting rod to reduce cold spots in said region. It is further conceivable that other types of lasers or laser sources, such as fiber lasers, can be utilized.

[0079] At operation 1050, when the rotational orientation of the substrate reaches the second target orientation, the excitation of the high-energy source is stopped. The second target orientation can be received based on the rotational orientation of the base and / or the rotational positioning of the substrate. The second target orientation can be received by a controller and / or a sensor. The second target orientation can indicate the position and / or positioning of the substrate and / or the position and / or positioning of the base within the processing chamber. The second target orientation can also indicate the speed and / or timing of the substrate and / or base within the processing chamber. Method 1000 can be repeated as the substrate and / or base rotates further within the processing chamber.

[0080] The tests performed and the results indicate that, by utilizing the equipment and methods described herein at a distance of approximately 105 mm to approximately 120 mm from the center of the substrate within the process chamber, the substrate is optimally conditioned because the decrease in resistivity (dip) is reduced, and cold spots on the substrate are appropriately compensated, such as... Figure 11 As shown in the diagram. Therefore, heating of the positioned points and regions is applied to the substrate via a high-energy radiation source assembly to control the amount of energy going to the substrate. As the substrate rotates within the process chamber, certain and specific areas of the substrate can be adjusted, thereby reducing troughs in the substrate profile and improving the substrate profile, because the high-energy radiation source assembly creates a narrow power band for performing localized heating.

[0081] The advantages of this disclosure include a reduction in the number of cold spots associated with the substrate. Reduced temperature non-uniformity within the substrate further results in a substrate with a more uniform surface. Cost reduction is also achieved as substrate quality increases. Additional advantages include precise localized heating of the substrate for ultra-fine-tuning of temperature uniformity.

[0082] In summary, the embodiments described herein provide an epitaxial deposition chamber including a high-energy radiation source assembly for providing localized heating of the substrate during processing. During substrate rotation within the chamber, energy can be focused onto an area of ​​approximately 10 mm, thereby locally heating and adjusting specific locations of the substrate, such as those adjacent to the lifting rod, at specific time intervals. The energy from the high-energy beam can provide a decrease in the resistivity profile of the implanted substrate during annealing. The high-energy radiation source assembly may be a diode laser system positioned to direct energy to a region of the substrate between approximately 100 mm and approximately 120 mm from the center of the substrate.

[0083] While the foregoing describes embodiments of this disclosure, other and further embodiments of this disclosure may be designed without departing from the basic scope of this disclosure, the scope of which is defined by the following claims.

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