Rapid thermal processing system with cooling system

Abstract

The present disclosure provides an apparatus, system, and method for processing a workpiece. In one example, the method for performing a spike annealing rapid thermal process may include controlling a heat source to begin heating a workpiece supported on a workpiece support in a processing chamber. The method may also include receiving data indicating the temperature of the workpiece. Furthermore, the method may include monitoring the temperature of the workpiece relative to a temperature set point. Furthermore, the method may include controlling a heat source to stop heating the workpiece based at least in part on the workpiece reaching the temperature set point. Furthermore, the method may include controlling a cooling system to begin flowing cooling gas through the workpiece at a rate of approximately 300 slm or greater based at least in part on the workpiece reaching the temperature set point to reduce the t50 peak width of the workpiece.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Application Serial No. 63 / 066,854, filed on August 18, 2020, entitled “RAPID THERMAL PROCESSING SYSTEM WITH COOLING SYSTEM,” which is incorporated herein by reference. Technical Field

[0003] The present disclosure relates generally to thermal processing systems, and more particularly to rapid thermal processing systems with cooling systems. Background Art

[0004] As used herein, a thermal processing chamber refers to a system for heating a workpiece, such as a semiconductor workpiece (e.g., a semiconductor wafer). Such a system may include a support plate for supporting one or more workpieces and an energy source for heating the workpieces, such as a heat lamp, laser, or other heat source. During thermal processing, the workpieces may be heated under controlled conditions according to a process protocol.

[0005] Many thermal processing processes require heating a workpiece within a range of temperatures to allow for various chemical and physical transformations to occur when the workpiece is fabricated into a device. For example, in rapid thermal processing, a workpiece can be heated by an array of lamps through a support plate to a temperature of approximately 300°C to approximately 1,200°C in a duration typically less than a few minutes. Summary of the Invention

[0006] Aspects and advantages of the embodiments of the present disclosure will be set forth in part in the following description, or may be learned from the description, or may be learned through practice of the embodiments.

[0007] One exemplary aspect of the present disclosure relates to a thermal treatment system for performing rapid thermal processing of semiconductor workpieces. The system includes a processing chamber and a workpiece support configured to support a workpiece within the processing chamber. The system also includes a heat source configured to heat the workpiece and a temperature measurement system configured to generate data indicating the temperature of the workpiece. In addition, the system includes a cooling system configured to flow a cooling gas through the workpiece supported on the workpiece support. In addition, the system includes a controller configured to control the heat source and the cooling system based at least in part on the data indicating the temperature of the workpiece, providing a cooling gas flow into the processing chamber at a rate of approximately 300 slm or greater to reduce the t50 peak width of the workpiece during thermal processing.

[0008] Other example aspects of the present disclosure relate to systems, methods, apparatus, and processes for performing rapid thermal processing of semiconductor workpieces.

[0009] These and other features, aspects and advantages of various embodiments will be better understood with reference to the following description and appended claims.The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the relevant principles. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] A detailed discussion of the embodiments is set forth for persons of ordinary skill in the art in the specification with reference to the accompanying drawings, in which:

[0011] Figure 1 depicts a rapid thermal processing system according to an example embodiment of the present disclosure;

[0012] Figure 2 Depicted is a cross-sectional view of an example cooling system for a thermal processing system according to an example embodiment of the present disclosure.

[0013] Figure 3 depicts an exploded perspective view of an example cooling system for a thermal processing system according to an example embodiment of the present disclosure;

[0014] Figure 4 Depicting a partial perspective view of an example cooling system for a thermal processing system according to an example embodiment of the present disclosure, particularly showing a gas supply portion of the cooling system;

[0015] Figure 5 Depicted is a top-down view of a distribution plate of an example cooling system of a thermal processing system according to an example embodiment of the present disclosure.

[0016] Figure 6 depicts a perspective view of mechanical fasteners of an example cooling system of a thermal management system according to an example embodiment of the present disclosure;

[0017] Figure 7 Depicting a bottom perspective view of an example cooling system of a thermal processing system according to an example embodiment of the present disclosure, particularly showing mechanical fasteners coupled to a cover plate of the cooling system;

[0018] Figure 8 Depicting a partial perspective view of an example cooling system of a thermal processing system according to an example embodiment of the present disclosure, particularly illustrating a flexible flange of a cover plate of the cooling system;

[0019] Figure 9 depicts an example temperature-time curve for a thermal processing system according to an example embodiment of the present disclosure;

[0020] Figure 10 depicts an example temperature-time curve for a thermal processing system according to an example embodiment of the present disclosure;

[0021] Figure 11A flowchart depicting an example method according to an example embodiment of the present disclosure; and

[0022] Figure 12 Depicted is a flowchart of another example method according to an example embodiment of the present disclosure. Specific embodiments

[0023] Reference will now be made in detail to the embodiments, one or more examples of which are illustrated in the accompanying drawings. Each example is provided by way of explanation of the embodiments and does not limit the present disclosure. In fact, it will be apparent to those skilled in the art that various modifications and variations may be made to the embodiments without departing from the scope or spirit of the present disclosure. For example, features shown or described as part of one embodiment may be used together with another embodiment to produce yet another embodiment. Therefore, aspects of the present disclosure are intended to encompass such modifications and variations.

[0024] Example aspects of the present disclosure relate to thermal treatment systems, such as rapid thermal processing (RTP) systems, for workpieces, such as semiconductor workpieces (e.g., silicon workpieces). Specifically, example aspects of the present disclosure relate to more tightly controlling temperature profiles during thermal treatment processes, such as spike annealing processes. A spike annealing process can be a thermal treatment that heats a workpiece to a high temperature in a matter of seconds or less. For example, a spike annealing process can be used to activate dopants in a workpiece, such as a silicon wafer.

[0025] At high temperatures, dopant atoms can diffuse into the workpiece at high rates, with most of this diffusion occurring at the peak annealing temperature required to activate the dopants. As performance demands increase and device dimensions decrease in semiconductor device manufacturing, the spike annealing heating profile may need to be tightly controlled as precisely as possible to subject the workpiece to the temperature conditions required to activate the dopants while limiting dopant diffusion.

[0026] According to exemplary aspects of the present disclosure, a cooling system can be disposed proximate to a workpiece (e.g., a semiconductor material or wafer) that is configured to be heated by light emitted by one or more heat sources (e.g., a lamp heat source, a laser, or any other suitable light source). The cooling system can be configured to supply a cooling gas flow through the workpiece to increase the cooling rate of the workpiece. In some embodiments, the cooling system can provide a cooling gas flow into the processing chamber at a rate of approximately 300 slm or greater to reduce the t50 peak width of the workpiece during the heat treatment process.

[0027] For example, the cooling system may include a distribution plate positioned axially adjacent to the workpiece support, wherein the distribution plate may have a surface parallel to the workpiece support and perpendicular to the axial direction (e.g., a first surface and a second surface extending perpendicularly to the axial direction) and a plurality of holes extending axially therethrough, wherein each of the plurality of holes in the distribution plate is at a different radial distance from the center of the distribution plate. The cooling system may also include a cover plate positioned axially adjacent to the distribution plate and relative to the workpiece support, and a collar axially coupled between the distribution plate and the cover plate, such that the collar, the distribution plate, and the cover plate can together define an internal chamber. A gas supply portion of the cooling device can be coupled to the collar to provide cooling gas from a gas source to the internal chamber. The cooling gas provided to the internal chamber can flow out of the internal chamber and through the workpiece surface through the plurality of holes in the distribution plate.

[0028] In some exemplary aspects of the present disclosure, each of the plurality of holes has the same cross-sectional area. However, in some aspects of the present subject matter, the shape of the plurality of holes can vary with radial distance. For example, in some aspects of the present subject matter, the plurality of holes can gradually elongate radially as the radial distance from the center of the distribution plate decreases, while maintaining the same azimuthal distance across which each of the plurality of holes extends.

[0029] In addition, in some aspects of the present disclosure, the gas supply can be configured to improve the distribution of gas through the distribution plate and, therefore, across the workpiece surface. For example, in some aspects, the gas supply can have an inlet plate coupled to the collar and extending in an azimuth direction between a first end and a second end of the collar spaced apart by a gap distance, wherein the inlet plate can include a plurality of inlet openings spaced apart in the azimuth direction. In some aspects, the gas supply can also include a plurality of inlet tubes, wherein each of the plurality of inlet tubes connects a respective one of the plurality of inlet openings to a gas source. In addition, in some aspects, the gas supply can include a baffle extending along at least a portion of the gap distance and spaced radially inward from the inlet plate, the baffle having a plurality of diffusion openings. In some aspects, the plurality of diffusion openings of the baffle and the plurality of inlet openings of the inlet plate can be spaced apart in the azimuth direction, alternating in the azimuth direction, or both.

[0030] Furthermore, in some aspects of the present disclosure, the cover plate can be clamped to the distribution plate to seal or airtightly seal the internal chamber of the cooling system. For example, in one aspect, the cover plate can include a plurality of flexible flanges, wherein each of the plurality of flexible flanges can extend along a corresponding azimuth portion and have an opening for receiving a corresponding mechanical fastener for coupling the cover plate, the collar, and the distribution plate together. During the clamping process, the flexible flanges can bend or shift toward the distribution plate to allow the mechanical fasteners to secure the cover plate to the distribution plate, clamping the collar therebetween.

[0031] Furthermore, in some aspects of the present disclosure, at least the distribution plate, cover plate, collar, and gas supply can be constructed from quartz. Thus, a portion of the cooling system, which can be constructed from quartz, can be fire-polished, thereby reducing the number of particles generated by the cooling system that could contaminate the workpiece during the annealing process.

[0032] In some embodiments, a controllable cooling system may be used in a thermal treatment system to reduce the peak width associated with a thermal treatment process (e.g., a spike annealing process). The peak width may describe the time interval during which a workpiece may be at or above a reference temperature, which may be determined by measuring the peak temperature (T) of a temperature-time curve (e.g., a spike annealing heating curve). 峰 ) by subtracting the temperature value (e.g., 50K). For example, the 50° temperature peak width (t50 peak width) is defined as the peak width when the workpiece surface temperature is higher than (T 峰 The reduced peak width obtained using a thermal process according to example aspects of the present disclosure can allow the thermal process to achieve an effective annealing cycle at relatively high temperatures while still reducing undesirable processes such as excessive dopant diffusion.

[0033] In some embodiments, the heat treatment system can include a controller to control the operation (e.g., flow rate) of a cooling system during heat treatment to reduce a peak width associated with the heat treatment process. For example, the controller can control the operation of the cooling system to cause cooling gas to flow through the workpiece at a rate of approximately 300 standard liters per minute (slm) or greater to reduce the t50 peak width of the workpiece, such that the t50 peak width of the heat treatment process is approximately 1.8 seconds or less. Furthermore, the controller can be configured to control the workpiece support to rotate the workpiece at least while the cooling system causes the cooling gas to flow through the workpiece.

[0034] In some embodiments, a controller (e.g., a computer, a microcontroller, other control device, etc.) may include one or more processors and one or more memory devices. The one or more memory devices may store computer-readable instructions that, when executed by the one or more processors, cause the one or more processors to perform operations such as controlling the operation of a cooling system during thermal processing, or other suitable operations as described below.

[0035] One exemplary aspect of the present disclosure relates to a method for controlling the operation of a thermal treatment system. The method may include activating a heat source to emit light to heat a workpiece for a spike annealing process. The method may include obtaining data indicating a temperature of the workpiece during the spike annealing heating process. The method may also include monitoring the temperature of the workpiece relative to a temperature set point. In addition, the method may include controlling the heat source to stop heating the workpiece based at least in part on the workpiece reaching the temperature set point. In addition, the method may include controlling a cooling system to begin flowing a cooling gas through the workpiece at a rate of approximately 300 slm or greater based at least in part on the workpiece reaching the temperature set point to reduce a t50 peak width of the workpiece.

[0036] Another example aspect of the present disclosure relates to a method for controlling operation of a thermal treatment system. The method may include activating a heat source to emit light to heat a workpiece for a spike annealing process. The method may include determining the expiration of a time interval after activating the heat source during the spike annealing process. The method may include controlling the heat source to stop heating the workpiece and controlling a cooling system to begin flowing a cooling gas through the workpiece at a rate of approximately 300 slm or greater to reduce a t50 peak width of the workpiece upon expiration of the time interval.

[0037] For purposes of illustration and discussion, aspects of the present disclosure are discussed with reference to a "workpiece," "wafer," or semiconductor wafer. One of ordinary skill in the art, using the disclosure provided herein, will understand that the example aspects of the present disclosure can be used in connection with any semiconductor substrate or other suitable substrate. Furthermore, the use of the term "about" in conjunction with a numerical value is intended to refer to within ten percent (10%) of the stated value.

[0038] Referring now to the accompanying drawings, Figure 1 A thermal processing system 100 according to an example embodiment of the present disclosure is depicted. As shown, the thermal processing system 100 can include a processing chamber 105. In some embodiments, the processing chamber 105 can be at least partially defined by quartz windows 107 of the thermal processing system 100. For example, one of the quartz windows 107 can at least partially define a ceiling of the processing chamber 105, and another of the quartz windows 107 can at least partially define a floor or bottom surface of the processing chamber 105. In some embodiments, the quartz window 107 can be doped with hydroxide OH. It should be understood that one or more surfaces defining the processing chamber 105 can be formed of any suitable material. For example, in some embodiments, one or more surfaces defining the processing chamber 105 can be formed of quartz.

[0039] As shown, the thermal processing system 100 may include a Figure 1) and a closed position (not shown) to allow selective access to the processing chamber 105. For example, the door 110 can be moved to an open position to allow a workpiece 120 to be positioned within the processing chamber 105. In some embodiments, the workpiece 120 can be at least partially supported by support pins 130, 132 of a lower one of the quartz windows 107. In this manner, heat associated with emitting light into the lower quartz window 107 can be transferred to the workpiece 120 via the support pins 130, 132. In some embodiments, the workpiece 120 can be rotated within the processing chamber 105, for example, during a heat treatment process. For example, the support pins 130, 132 can be configured to rotate relative to the lower one of the quartz windows 107. Furthermore, once the workpiece 120 is positioned on the support pins 130, 132 of the lower quartz window 107, the door 110 can be moved to a closed position. In some embodiments, when the door 110 is in the closed position, the processing chamber 105 can be sealed from the external environment.

[0040] In some embodiments, one or more surfaces defining the processing chamber 105 may define a gas inlet 140. In this manner, a process gas provided from a gas source may flow into the processing chamber 105 through the gas inlet 140. In some embodiments, the process gas may include an inert gas that does not react with the workpiece 120. Alternatively, the process gas may include a reactive gas that reacts with the workpiece 120 to deposit a material layer on the surface of the workpiece 120. For example, in some embodiments, the process gas may include ammonium NH3 gas. However, it should be understood that the process gas may include any suitable reactive gas. For example, in alternative embodiments, the reactive gas may include H2 gas.

[0041] The thermal treatment system 100 can include one or more heat sources 150 disposed outside of the processing chamber 105. For example, the heat sources 150 can be positioned above the processing chamber 105, below the processing chamber 105, or above and below the processing chamber 105. The one or more heat sources 150 can be configured to emit light toward the workpiece 120 during a thermal treatment process (e.g., rapid thermal processing or spike annealing thermal processing). More specifically, during the thermal treatment process, the heat sources 150 positioned above the processing chamber 105 can be configured to emit light toward an upper surface or side of the workpiece 120, and the heat sources 150 positioned below the processing chamber 105 can be configured to emit light toward a lower surface or side of the workpiece 120. The light emitted from the one or more heat sources 150 can increase the temperature of the workpiece 120. In some embodiments, the one or more heat sources 150 can increase the temperature of the workpiece 120 by more than approximately 500° C. within a predetermined amount of time (e.g., less than 2 seconds).

[0042] It should be understood that the one or more heat sources 150 can include any suitable type of heat source configured to emit light. For example, in some embodiments, the one or more heat sources 150 can include one or more heat lamps (e.g., linear lamps). In alternative embodiments, the one or more heat sources 150 can include one or more lasers configured to emit a laser beam onto the workpiece 120. It should also be understood that the heat sources 150 positioned above the processing chamber 105 can be controlled separately from the heat sources 150 positioned below the processing chamber 105 or can be controlled together to perform the heat treatment process.

[0043] In some embodiments, the thermal processing system 100 can include one or more reflectors 152 positioned such that light emitted from the one or more heat sources 150 is directed toward or towards the processing chamber 105. More specifically, the reflectors 152 can direct light emitted from the one or more heat sources 150 toward or towards the corresponding quartz windows 107, such that the light can pass through the corresponding quartz windows 107 and enter the processing chamber 105. It should be understood that at least a portion of the light that enters the processing chamber 105 through the quartz windows 107 can be emitted onto the workpiece 120. In this manner, as described above, the light emitted from the one or more heat sources 150 can increase the temperature of the workpiece 120 during a thermal processing process, such as a rapid thermal processing process (e.g., a spike annealing process).

[0044] In one embodiment, the thermal processing system 100 may include a temperature measurement system 178 configured to generate and transmit data indicative of the temperature of the workpiece 120. The temperature measurement system 178 may include one or more temperature sensors 180. The temperature sensors 180 may include pyrometers, thermocouples, thermistors, or any other suitable temperature sensor or combination of temperature sensors. Depending on the type of sensor, the temperature sensors 180 may be positioned within the processing chamber 105 or may be positioned external to the processing chamber 105. For example, if the temperature sensor 180 is a pyrometer, the pyrometer does not need to contact the workpiece 120 and thus may be positioned external to the chamber 105. However, if the temperature sensor 180 is a thermocouple, the thermocouple must contact the workpiece 120 and thus may be positioned internal to the chamber 105. Furthermore, the temperature sensor 180 may be communicatively coupled to the controller 190 via a wired connection, a wireless connection, or both, so that data generated by the sensor 180 indicative of the temperature of the workpiece 120 may be provided to the controller 190.

[0045] According to an exemplary aspect of the present disclosure, the heat treatment system 100 includes a cooling system 200, as will be described in greater detail below, which is configured to selectively flow cooling gas from a gas source 214 through the workpiece 120 during heat treatment. The controller 190 can control the operation of the heat source 150 and the cooling system 200 (e.g., the flow rate of the cooling gas flowing through the workpiece 120) during heat treatment to reduce the peak width associated with the heat treatment process. For example, the controller 190 can control the operation of the cooling system 200 so that the heat treatment process has a t50 peak width of approximately 1.8 seconds or less, such as approximately 1.5 seconds or less. In addition, the controller 190 can control the rotation of the workpiece 120. For example, during heat treatment, such as when operating the cooling system 200, the controller 190 can control a workpiece support (e.g., a support pin) so that the workpiece 120 rotates.

[0046] In some embodiments, the controller 190 or control device (e.g., a computer, microcontroller, other control device, etc.) may include one or more processors and one or more memory devices. The one or more memory devices may store computer-readable instructions that, when executed by the one or more processors, cause the one or more processors to perform operations such as turning the heat source 150 on or off, controlling the operation of the cooling system 200 during thermal processing, or other suitable operations as described below.

[0047] Now turn Figure 2-8 , depicts example aspects of a cooling system 200 for a thermal processing system 100. More specifically, Figure 2 depicts a cross-sectional view of a cooling system 200, and Figure 3 An exploded perspective view of the cooling system 200 is depicted. Additionally, Figure 4 A partial perspective view of the cooling system 200 is depicted, specifically showing the gas supply portion of the cooling system 200. In addition, Figure 5 A top-down view of the distribution plate of the cooling system 200 is depicted. Additionally, Figure 6 and Figure 7 The mechanical fasteners of the cooling system 200 are depicted. In addition, Figure 8 A partial perspective view of the cooling system 200 is depicted, particularly showing the flexible flange of the cover plate of the cooling system 200 .

[0048] like Figure 2As shown, the cooling system 200 includes a cover plate 202, a distribution plate 204, a collar 206, and a gas supply 208, each of which can be made of quartz. The cover plate 202 extends along the axial direction X1 between an upper surface 202A and a lower surface 202B. The cover plate 202 is continuous so that it has no axially extending openings therethrough through which cooling gas can flow. The distribution plate 204 similarly extends along the axial direction X1 between an upper surface 204A and a lower surface 204B, wherein the lower surface 204B is axially closer to the processing chamber 105 ( Figure 1 ) in the artifacts (e.g., Figure 1 At least the lower surface 204B of the distribution plate 204 extends perpendicularly to the axial direction X1 so that it is substantially parallel to the workpiece surface ( Figure 1 ) or workpiece supports 130, 132 ( Figure 1 ) support plane. Unlike the cover plate 202, the distribution plate 204 has a plurality of holes 210 extending therethrough, as will be described in more detail below. In one embodiment, the holes 210 extend along the axial direction X1. However, in other embodiments, the holes 210 may alternatively extend at an angle relative to the axial direction X1. The cover plate 202 is generally axially adjacent to the distribution plate 204 and is positioned opposite the workpiece support 130 ( Figure 1 ).

[0049] The collar 206 extends radially between an outer side 206A and an inner side 206B. The collar 206 is axially positioned between the lower surface 202B of the cover plate 202 and the upper surface 204A of the distribution plate 204, such that an internal chamber 212 is defined between the radially inner side 206B of the collar 206, the lower surface 202B of the cover plate 202, and the upper surface 204A of the distribution plate 204. The gas supply 208 is configured to selectively supply cooling gas from a gas source 214 to the internal chamber 212. The cooling gas supplied to the internal chamber 212 can then flow from the internal chamber 212 through the aperture 210 and through the workpiece supported beneath the cooling system 200.

[0050] like Figure 3As specifically shown in the exploded view of the cooling system 200 in FIG. 1 , the cover plate 202 can be directly coupled to the distribution plate 204 via a plurality of mechanical fasteners 216, as will be described in greater detail below. Furthermore, the collar 206 has a gap extending along an azimuth direction A1 between a first azimuth end 218A and a second azimuth end 218B. The first and second azimuth ends 218A, 218B are separated by a gap distance D1 along the azimuth direction A1. The gas supply 208 includes an inlet plate 220 that can be mounted or coupled between the first and second azimuth ends 218A, 218B of the collar 206. When mounted, the inlet plate 220 extends along the azimuth direction A1 across the gap distance D1 to define at least a portion of the interior chamber 212. However, it should be understood that the inlet plate 220 can alternatively extend linearly between the first and second ends 218A, 218B of the collar. In one aspect, the inlet plate 220 includes a plurality of inlet openings 222 spaced apart along an azimuth direction A1, through which cooling gas is supplied to the interior chamber 212, as will be described in more detail below. In some embodiments, the gas supply 208 further includes a baffle 226. The baffle 226 is spaced radially inward from the inlet plate 220 and extends along at least a portion of the gap distance D1. For example, in some aspects, the baffle 226 is coupled to a radially inward portion of the inlet plate 220 to define at least a portion of the interior chamber 212. In some aspects, the baffle 226 includes a plurality of diffusion openings 228, through which the cooling gas supplied through the inlet openings 222 must pass before being received into the interior chamber 212, as will be described in more detail below.

[0051] Now turn Figure 4The gas supply 208 is configured to evenly distribute the cooling gas across the distribution plate 204. For example, as described above, the inlet openings 222 of the inlet plate 220 are spaced apart along the azimuthal direction A1. For example, in some embodiments, the inlet openings 222 may be evenly spaced apart along the azimuthal direction A1. Furthermore, in some embodiments, the inlet openings 222 may have the same cross-sectional area. Each inlet opening 222 is in turn coupled to the cooling gas source 214 via a corresponding inlet tube 230. More specifically, each inlet tube 230 is connected at its first end to a corresponding one of the inlet openings 222 and at its second end to an adapter 232. The adapter 232 is configured to connect the second end of the inlet tube 230 to the gas source 214. However, it should be understood that in some embodiments, each inlet tube 230 may be individually connected to the gas source 214 (e.g., via a corresponding adapter or connector). The inlet openings 222 and tubes 230 divide the cooling gas flow from the gas source 214, allowing the gas to enter the internal chamber at multiple azimuthal locations. In some embodiments, the inlet openings 222 and tubes 230 evenly divide the cooling gas flow from the gas source 214. However, in some embodiments, different pairs of inlet openings 222 and tubes 230 can provide different proportions of the cooling gas flow from the gas source 214 to the interior chamber. Although five inlet openings 222 and tubes 230 are shown, the gas supply 208 can include any other suitable number, such as four or fewer, or six or more, for example.

[0052] Furthermore, in some embodiments, the baffle 226 is positioned radially inward of the inlet plate 220 and includes its own diffusion openings 228 as described above. In some aspects, the diffusion openings 228 have a smaller cross-sectional area than the inlet openings 222 and are more numerous than the inlet openings 222, such that the gas flowing through the inlet openings 222 is further divided by the diffusion openings 228. In one aspect, the diffusion openings 228 can be positioned at a different azimuth position than the inlet openings 222. For example, Figure 4 The protrusions 222P of the middle inlet opening 222 illustrate the corresponding azimuthal position of the inlet opening 222 relative to the diffuser openings 228. The protrusions 222P of the inlet opening 222 are spaced apart from the diffuser openings 228 along the azimuthal direction A1. Furthermore, the protrusions 222P of the inlet opening 222 alternate with the diffuser openings 228 along the azimuthal direction A1, such that at least one of the diffuser openings 228 is positioned between each pair of adjacent protrusions 222P along the azimuthal direction A1. By offsetting the inlet openings 222 and diffuser openings 228 along the azimuthal direction A1, more turbulent flow is generated between the inlet plate 220 and the baffle 226, which provides a more even distribution of cooling gas through the diffuser openings 228.

[0053] like Figure 4As further shown, in one aspect, the access plate 220 and the collar 206 have locking features that couple together to form an airtight seal. More specifically, the access plate 220 has a first channel 234A for receiving the first orientation end 218A of the collar 206 and a similar second channel 234B for receiving the second orientation end 218B of the collar 206. In one aspect, the access plate 220 also includes a first lip or protrusion 236A that is receivable within a first recess 238A formed in the collar 206 near the first orientation end 218A, and a similar second lip or protrusion 236B that is receivable within a second recess 238B formed in the collar 206 near the second orientation end 218B. Such locking features 234 , 236 , 238 form a gas-tight seal such that when cover plate 202 is coupled to distribution plate 204 with collar 206 and inlet plate 220 therebetween, cooling gas can only enter interior chamber 212 through inlet plate 220 and exit interior chamber 212 through holes 210 in distribution plate 204 .

[0054] Additionally, in one embodiment, the baffle 226 is configured to be coupled to the inlet plate 220 as noted above and Figure 4 For example, the inlet plate 220 includes a first channel 240A for receiving a first azimuthal end 242A of the baffle 226 and a similar second channel 240B for receiving a second azimuthal end 242B of the baffle 226. When the cover plate 202 is coupled to the distribution plate 204 with the collar 206, the inlet plate 220, and the baffle 226 therebetween, such channels 240A, 240B can form a gas-tight seal with the baffle 226, such that cooling gas can only enter the interior chamber 212 through the diffusion openings 228 and exit the interior chamber 212 through the holes 210 in the distribution plate 204.

[0055] Now turn Figure 5 The distribution plate 204 is individually configured to evenly distribute the cooling gas flowing therethrough over the workpiece. For example, each hole 210 in the distribution plate 204 is spaced a different radial distance from the center C1 of the distribution plate 204. For example, a first hole 210A, the radially innermost of the holes 210 in the distribution plate 204, is spaced a first distance R1 from the center C1, and a second hole 210B, the radially outermost of the holes 210 in the distribution plate 204, is spaced a second distance R2 from the center C1. In one embodiment, the holes 210 in the distribution plate 204 spiral outward from the first hole 210A to the second hole 210B at increasing radial distances.

[0056] In some aspects, the holes 210 in the distribution plate 204 have the same cross-sectional area. Furthermore, in one aspect, the holes 210 extend across the same azimuthal distance. To ensure that the holes 210 have the same cross-sectional area and extend across the same azimuthal distance, the holes 210 have different shapes. More specifically, as the radial distance from the center C1 of the distribution plate 204 decreases, the holes 210 become increasingly elongated in the radial direction. For example, as the holes 210 spiral outward away from the first hole 210A, the radial distance extended by each successive hole 210 becomes increasingly shorter until reaching the second hole 210B that extends across the shortest radial distance. For example, the first hole 210A extends along a first radial distance L1 and the second hole 210B extends along a second radial distance L2, where the first radial distance L1 is greater than the second radial distance L2.

[0057] Additionally, the distribution plate 204 has a plurality of mounting holes 250 for receiving the mechanical fasteners 216 ( Figure 3 ) to cover plate 202 ( Figure 3 ) is mounted to the distribution plate 204. The mounting hole 250 is spaced apart from the center C1 of the distribution plate 204 by a radial distance RM1, wherein the radial distance RM1 is greater than the second radial distance L2 where the radially outermost hole 210B is located. In one embodiment, the collar 206, the inlet plate 220, and the baffle 226 ( Figure 4 ) is configured to be positioned at a radial distance between the second radial distance L2 and the radial distance RM1. In some embodiments, the mounting holes 250 are evenly spaced apart along the azimuth direction A1.

[0058] As reference Figure 6-8 As described, in one embodiment, each mechanical fastener 216 is configured as a bayonet pin (hereinafter referred to as a "bayonet 216"). The bayonet 216 extends between a first portion 216A at its first end and a second portion 216B at its second end. Figure 6 and 7 As specifically shown in FIG, the bayonet 216 further includes a third portion 216C and an optional fourth portion 216D, the third portion 216C being positioned between the first portion 216A and the fourth portion 216D, and the fourth portion 216D being positioned between the third portion 216C and the second portion 216B. Figure 6 As shown, first portion 216A has a first diameter or width DB1, second portion 216B has a second diameter or width DB2, third portion 216C has a third diameter or width DB3, and fourth portion 216C has a fourth diameter or width DB4. First diameter DB1 is greater than second diameter DB2, second diameter DB2 is greater than third diameter DB3, and third diameter DB3 is greater than fourth diameter DB4.

[0059] When the bayonet 216 is in the installed or secured position, the first portion 216A of the bayonet 216 is configured to retain an opening or recess 260 ( 260A ) in the cover plate 202 having a diameter substantially corresponding to the first diameter DB1. Figure 8 ) so that the first portion 216A of the bayonet 216 cannot completely pass through the cover plate 202. In addition, the third portion 216C of the bayonet 216 is configured to at least partially extend through the cover plate 202 (e.g., Figure 8 through the portion below the recess 260 of the cover plate 202) and at least partially through the Figure 7 204. In addition, the fourth portion 216D of the bayonet 216, when present, extends at least partially through the mounting hole 250 in the distribution plate 204 as shown in FIG. Figure 7 Mounting holes 250 are shown in the distribution plate 204. Additionally, the second portion 216B is configured to abut or rest against the lower surface 204B of the distribution plate 204.

[0060] More specifically, the mounting hole 250 has a first contour portion 250A and a second contour portion 250B. The first contour portion 250A is generally circular and has a diameter or width W1 that generally corresponds to the third diameter DB3 of the third portion 216C of the bayonet. The second contour portion 250B is generally rectangular and intersects the first contour portion 250A, wherein the second contour portion 250B has a width W2 that generally corresponds to the width WB1 of the second portion 216B of the bayonet 216 in the first direction and has a width W3 that generally corresponds to the second diameter DB2 of the second portion 216B of the bayonet 216 in the second direction. The bayonet 216 is configured to be in the first rotational position ( Figure 8 ) is inserted through the mounting hole 250 so that at least a portion of the second portion 216B of the bayonet 216 and the third and fourth portions 216C, 216D of the bayonet 216 are configured to pass through the first contour 250A and the remainder of the second portion 216B of the bayonet 216 passes through the second contour 250B. Once the bayonet 216 is fully inserted through the mounting hole 250 so that the second portion 216B of the bayonet 216 extends through the mounting hole 250, the bayonet 216 can be rotated from the first rotational position ( Figure 8 ) rotates to the second rotation position ( Figure 7 ), such that the bayonet 216 cannot be passed through or removed from the mounting hole 250 without first rotating back to the first rotational position.

[0061] Specific as Figure 8As shown, when the cover plate 202 is located on the collar 206 but is not fastened or coupled to the distribution plate 204, the bayonet 216 cannot extend through the mounting hole 250. Therefore, the cover plate 202 includes a plurality of flexible flanges 262 extending along its periphery. Each flange 262 extends along a corresponding azimuth portion of the cover plate 202. Each flange 262 includes a corresponding opening 260 for receiving the bayonet 216. When it is desired to couple the cover plate 202 to the distribution plate 204, the bayonet 216 can be inserted into the corresponding opening 260 and an external force can be applied in the axial direction X1 to bend or flex the flange to the mounting position (indicated by the dotted line). When the bayonet 216 is rotated to the second rotational position ( Figure 7 ), the force required to bend or flex the flange into the installed position can then be provided by the corresponding bayonet 216. This continuous force helps to seal the internal chamber 212 ( Figure 2 ) to prevent the cooling gas from passing through the opening 210 ( Figure 2 ) outside of chamber 212.

[0062] It should be understood that the mechanical fasteners 216 may be configured as any other suitable mechanical fasteners or combinations of fasteners, including but not limited to screws, bolts, rivets, and / or the like.

[0063] It should also be understood that cooling system 200 can be constructed primarily or entirely of quartz. For example, in one embodiment, at least cover plate 202, distribution plate 204, collar 206, inlet plate 220, baffle 226, and inlet tube 230 each comprise quartz. Furthermore, in some embodiments, fastener 216 is constructed of quartz. Components of cooling system 200 constructed of quartz can be fire-polished to reduce the amount of particles generated by cooling system 200 that could contaminate the workpiece during the annealing process.

[0064] Figure 9 An example temperature-time curve 300 of the thermal processing system 100 is depicted according to an example embodiment of the present disclosure. Figure 9As can be seen, after the first time period 310, a spike annealing process occurs during the second time period 320. The heating curve 330 (solid curve) can be generated by conventional spike annealing. In conventional spike annealing, one or more heat sources (e.g., heat source 150) are controlled to emit light to heat the workpiece while monitoring the temperature of the workpiece relative to a temperature set point 334. In one aspect, the temperature set point 334 is within approximately 20% of the peak temperature of a heating curve 340 of the thermal processing system 100. The heat source can be configured to stop emitting light once the temperature of the workpiece reaches or exceeds the temperature set point 334. The conventional spike anneal can have a peak width (t50 peak width) 332 of the heating curve 330 at 50°C (e.g., 50K). The heating curve 340 (dashed curve) can be generated by the thermal processing system 100 by controlling the cooling system 200 to begin flowing cooling gas through the workpiece at a rate of 300 slm or greater based at least on the temperature of the workpiece reaching or exceeding the temperature set point 334. For example, when the temperature of the workpiece 120 reaches the temperature set point 334, the cooling system 200 can be controlled to begin flowing the cooling gas through the workpiece. Alternatively, the cooling system 200 can be controlled to begin flowing the cooling gas through the workpiece when a second temperature set point (not shown) expires, where the second temperature set point can be between the first temperature set point 334 and the peak desired temperature, or can be lower than the first temperature set point 334. The t50 peak width 342 of the heating curve 340 of the thermal processing system 100 using the cooling system 200 is less than the t50 peak width 332 of the heating curve 330 of the conventional spike annealing process.

[0065] Figure 10 An example temperature-time curve 400 of the thermal processing system 100 is depicted according to an example embodiment of the present disclosure. Figure 10As can be seen, after the first time period 410, a spike annealing process occurs during a second time period 420. A heating curve 430 (solid curve) can be generated by a conventional spike annealing process. In a conventional spike annealing process, one or more heat sources (e.g., heat source 150) are controlled to emit light to heat the workpiece for a predetermined time interval 420A corresponding to a second time period 420A during which the workpiece can reach a peak temperature. In one aspect, the predetermined time interval 420A is in the range of about 5 milliseconds to about 100 milliseconds. The conventional spike annealing process can have a peak width (t50 peak width) 432 of the heating curve 430 at a temperature of 50° (e.g., 50K). A heating curve 440 (dashed curve) can be generated by the thermal processing system 100 by controlling the cooling system 200 to begin flowing a cooling gas through the workpiece at a rate of 300 slm or greater based on at least the expiration of the predetermined time interval 420A during which the heat sources are operated. For example, upon the expiration of the time interval 420A, the cooling system 200 can be controlled to begin flowing the cooling gas through the workpiece. Alternatively, the cooling system 200 can be controlled to begin flowing the cooling gas through the workpiece when a second time interval (not shown) expires, wherein the second time interval can begin when the first time interval 420A expires and can be in the range of about 5 milliseconds to about 100 milliseconds. The t50 peak width 442 of the heating curve 340 of the thermal treatment system 100 using the cooling system 200 is smaller than the t50 peak width 432 of the heating curve 430 of the conventional spike annealing process.

[0066] Figure 11 A flow chart of an example method (500) according to an example embodiment of the present disclosure is depicted. Reference will be made by way of example to Figure 1 The method (500) is discussed with reference to the thermal processing system 100. The method (500) can be implemented in any suitable plasma processing apparatus. Figure 11 The steps are depicted as being performed in a particular order for purposes of illustration and discussion. One of ordinary skill in the art, using the disclosure provided herein, will appreciate that the various steps of any method described herein may be omitted, expanded, performed simultaneously, rearranged, and / or modified in various ways without departing from the scope of this disclosure. Furthermore, multiple steps (not shown) may be performed without departing from the scope of this disclosure.

[0067] At 502, the method 500 may include controlling a heat source to begin heating a workpiece supported on a workpiece support in a processing chamber. For example, the controller 190 of the thermal processing system 100 may control the heat source 150 to begin heating (i.e., emitting light toward) the workpiece 120 supported on the workpiece supports 130, 132 in the processing chamber 105.

[0068] At 504 , the method 500 may also include receiving data indicative of the workpiece temperature from a temperature measurement system during the spike annealing process. For example, the thermal processing system 100 may include one or more temperature sensors 180 that may generate and transmit data indicative of the temperature of the workpiece 120 .

[0069] Additionally, at (506), the method 500 may include monitoring the temperature of the workpiece relative to a temperature set point. For example, the controller 190 of the thermal processing system 100 may access a device indicating a temperature set point (e.g., Figure 9 The temperature set point may be within about 20% of the peak temperature of the heating profile associated with the spike annealing heating profile.

[0070] Furthermore, at 508, method 500 may include controlling the heat source to stop heating the workpiece based at least in part on the workpiece temperature reaching the temperature set point. For example, when the temperature of the workpiece 120 reaches or exceeds the temperature set point, controller 190 may control heat source 150 to stop heating (i.e., emitting light) to the workpiece 120.

[0071] Additionally, at 510, the method may include controlling the cooling system to begin flowing cooling gas through the workpiece at a rate of approximately 300 slm or greater based at least in part on the workpiece temperature reaching the temperature set point. For example, when the temperature of the workpiece 120 reaches or exceeds the temperature set point, the controller 190 may control the cooling system 200 of the thermal treatment system to begin flowing cooling gas through the workpiece 120 at a rate of approximately 300 slm or greater to reduce the t50 peak width of the workpiece.

[0072] Figure 12 A flow chart of an example method (600) according to an example embodiment of the present disclosure is depicted. Reference will be made by way of example to Figure 1 The method (600) is discussed with reference to the thermal processing system 100. The method (600) can be implemented in any suitable plasma processing apparatus. Figure 12 The steps are depicted as being performed in a particular order for purposes of illustration and discussion. One of ordinary skill in the art, using the disclosure provided herein, will appreciate that the various steps of any method described herein may be omitted, expanded, performed simultaneously, rearranged, and / or modified in various ways without departing from the scope of this disclosure. Furthermore, multiple steps (not shown) may be performed without departing from the scope of this disclosure.

[0073] At 602, the method 600 may include controlling a heat source to begin heating a workpiece supported on a workpiece support in a processing chamber. For example, the controller 190 of the thermal processing system 100 may control the heat source 150 to begin heating (i.e., emitting light toward) the workpiece 120 supported on the workpiece supports 130, 132 in the processing chamber 105.

[0074] Furthermore, at (604), the method 600 may include determining the expiration of a time interval after controlling the heat source to begin heating the workpiece. For example, the controller 190 of the heat treatment system 100 may determine the time interval (e.g., with reference to Figure 10 The expiration of the time interval 420A) described, for example, a time interval in the range of about 5 milliseconds to about 100 milliseconds.

[0075] Furthermore, at 606 , the method 600 may include controlling the heat source to stop heating the workpiece when the time interval expires. For example, the controller 190 of the heat treatment system 100 may control the heat source 150 to stop heating (i.e., emitting light thereto) when the time interval expires.

[0076] Furthermore, at 608, method 600 may include controlling the cooling system to begin flowing the cooling gas through the workpiece at a rate of approximately 300 slm or greater based at least in part on the expiration of the time interval. For example, when the time interval expires, controller 190 may control cooling system 200 of the thermal processing system to begin flowing the cooling gas through workpiece 120 at a rate of approximately 300 slm or greater to reduce the t50 peak width of the workpiece.

[0077] Although the subject matter has been described in detail with reference to specific example embodiments thereof, it should be understood that those skilled in the art may readily make changes, variations, and equivalents to these embodiments upon gaining an understanding of the foregoing. Accordingly, the scope of the present disclosure is intended to be exemplary and not limiting, and the present disclosure does not exclude the inclusion of such modifications, variations, and / or additions to the subject matter as would be apparent to one of ordinary skill in the art.

Claims

1. A thermal treatment system for rapid thermal treatment of a semiconductor workpiece, comprising: a processing chamber; a workpiece support configured to support a workpiece within the processing chamber; a heat source configured to heat the workpiece; a temperature measurement system configured to generate data indicative of a temperature of the workpiece; a cooling system configured to flow a cooling gas through the workpiece supported on the workpiece support, the cooling system comprising: a distribution plate positioned axially adjacent to the workpiece support, the distribution plate having a surface parallel to the workpiece support and perpendicular to the axial direction, the distribution plate having a plurality of holes extending axially therethrough, each of the plurality of holes of the distribution plate being a different radial distance from a center of the distribution plate, wherein the plurality of holes includes a first hole extending along a first radial distance and a second hole extending along a second radial distance, the first radial distance being greater than the second radial distance; A controller is configured to control the heat source and the cooling system based at least in part on the data indicating the temperature of the workpiece to provide a flow of cooling gas into the processing chamber at a rate of about 300 slm or greater to reduce a t50 peak width of the workpiece during thermal processing.

2. The system of claim 1, wherein: The cooling system further comprises: a cover plate axially adjacent to the distribution plate and positioned opposite the workpiece support; a collar axially coupled between the distribution plate and the cover plate, the collar, the distribution plate, and the cover plate together defining an interior chamber; and a gas supply coupled to the collar to provide the cooling gas from a gas source to the interior chamber, Wherein, the controller is configured to control the gas supply portion of the cooling system during a spike annealing thermal process.

3. The system of claim 1, wherein: Each hole in the plurality of holes has the same cross-sectional area.

4. The system of claim 3, wherein: The plurality of holes are radially elongated as the radial distance from the center of the distribution plate decreases, such that each hole in the plurality of holes extends along the same azimuthal distance.

5. The system of claim 2, wherein: The gas supply includes an inlet plate coupled to the collar and extending in an azimuth direction between first and second ends of the collar spaced apart by a gap distance, the inlet plate including a plurality of inlet openings spaced apart in the azimuth direction.

6. The system of claim 5, wherein: The gas supply further includes a plurality of inlet tubes, each of the plurality of inlet tubes connecting a corresponding one of the plurality of inlet openings to the gas source.

7. The system of claim 5, wherein: The gas supply also includes a baffle extending along at least a portion of the gap distance and spaced radially inward from the inlet plate, the baffle having a plurality of diffusion openings.

8. The system of claim 7, wherein: The plurality of diffusion openings of the baffle and the plurality of inlet openings of the inlet plate are spaced apart in the azimuthal direction, and The plurality of diffusion openings of the baffle and the plurality of inlet openings of the inlet plate are alternated along the azimuth direction.

9. The system of claim 2, wherein: The cover plate, the distribution plate, the collar, and the gas supply are composed of a quartz material.

10. The system of claim 1, wherein: The plurality of holes spiral outward from the first hole to the second hole.

11. A thermal processing system for performing rapid thermal processing on a semiconductor workpiece, comprising: a processing chamber; a workpiece support configured to support a workpiece within the processing chamber; a heat source configured to heat the workpiece; a temperature measurement system configured to generate data indicative of a temperature of the workpiece; a cooling system configured to flow a cooling gas through the workpiece supported on the workpiece support, the cooling system comprising: a distribution plate positioned axially adjacent to the workpiece support, the distribution plate having a surface parallel to the workpiece support and perpendicular to the axial direction, the distribution plate having a plurality of holes extending axially therethrough, each of the plurality of holes of the distribution plate being a different radial distance from a center of the distribution plate; a cover plate axially adjacent to the distribution plate and positioned opposite the workpiece support; a collar axially coupled between the distribution plate and the cover plate, the collar, the distribution plate, and the cover plate together defining an interior chamber; and A gas supply is coupled to the collar to provide the cooling gas from a gas source to the interior chamber, the gas supply including a plurality of inlet openings and a plurality of tubes such that gas entering the interior chamber is split to flow into the interior chamber from a plurality of different azimuthal positions.

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