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. In addition, the method may 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 cooling gas through the workpiece at a rate of approximately 300 slm or greater to reduce the t50 peak width of the workpiece based at least in part on the workpiece reaching the temperature set point.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Application Serial No. 63 / 066,856, 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 processing system for performing rapid thermal processing of a semiconductor workpiece. The system includes a processing chamber and a workpiece support configured to support the 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 indicative of the temperature of the workpiece. Furthermore, the system includes a cooling system configured to flow a cooling gas through the workpiece supported on the workpiece support, the cooling system including a plurality of cooling tubes arranged in a cooling plane, each of the plurality of cooling tubes having an inlet opening and a plurality of outlet openings.

[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 embodiments for those of ordinary skill in the art is set forth 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 depicts a perspective view of an example cooling system for a thermal processing system according to an example embodiment of the present disclosure;

[0013] Figure 3 Depicted is a bottom-up view of cooling tubes of an example cooling system of a thermal processing system according to an example embodiment of the present disclosure.

[0014] Figure 4 Depicted is a cross-sectional view of cooling tubes of an example cooling system of a thermal processing system according to an example embodiment of the present disclosure.

[0015] Figure 5 depicts an example temperature-time curve for a thermal processing system according to an example embodiment of the present disclosure;

[0016] Figure 6 depicts an example temperature-time curve for a thermal processing system according to an example embodiment of the present disclosure;

[0017] Figure 7 A flowchart depicting an example method according to an example embodiment of the present disclosure; and

[0018] Figure 8 Depicted is a flowchart of another example method according to an example embodiment of the present disclosure. Specific embodiments

[0019] 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.

[0020] 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.

[0021] 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.

[0022] 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.

[0023] More specifically, in some exemplary aspects, the cooling system includes a plurality of cooling tubes arranged in a cooling plane, each cooling tube having an inlet opening and a plurality of outlet openings. In some exemplary aspects, the plurality of cooling tubes includes exactly four cooling tubes. In one aspect, directly adjacent cooling tubes of the four cooling tubes are positioned perpendicular to each other. In some exemplary aspects, the cooling plane may be parallel to the workpiece plane. In addition, in some exemplary aspects, the plurality of cooling tubes may be spaced apart from the central axis of the workpiece. In addition, in some exemplary aspects, the plurality of cooling tubes may extend radially toward the central axis of the workpiece.

[0024] In some example aspects, a gas supply portion is coupled to the inlet openings of a plurality of cooling tubes to provide cooling gas from a gas source through the plurality of cooling tubes and out of the plurality of outlet openings of the plurality of cooling tubes. In some example aspects, the axis of each of the plurality of outlet openings of the plurality of cooling tubes is angled relative to the cooling plane toward the workpiece plane of the workpiece. In addition, in some example aspects, the plurality of outlet openings of the plurality of cooling tubes are radially spaced from the central axis of the workpiece. For example, on the one hand, each of the plurality of outlet openings of the plurality of cooling tubes is at a different radial distance from the central axis of the workpiece. Specifically, on the one hand, the radial distance between adjacent outlet openings in the plurality of outlet openings of each cooling tube in the plurality of cooling tubes decreases as the radial distance from the central axis of the workpiece increases. In addition, on the one hand, each of the plurality of outlet openings of the four cooling tubes has the same cross-sectional area.

[0025] In some exemplary aspects, the plurality of cooling tubes are constructed of quartz material. Thus, the cooling tubes can be fire-polished to reduce the amount of debris generated during the heat treatment process that might otherwise contaminate the workpiece.

[0026] 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 ) is obtained by subtracting the temperature value (such as 50K, etc.) from the peak width. 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 -50°). The peak width reduction achieved 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. In some aspects, the temperature measurement system can be configured to generate data indicative of the temperature of the workpiece.

[0027] In some embodiments, the heat treatment system can include a controller (e.g., one or more control devices) 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 supply 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.

[0028] In some embodiments, a controller (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 controlling the operation of a cooling system during thermal processing, or other suitable operations as described below.

[0029] 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 the 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 cooling gas through the workpiece at a rate of approximately 300 slm or greater to reduce the t50 peak width of the workpiece based at least in part on the workpiece reaching the temperature set point, the cooling system having a plurality of cooling tubes arranged in a cooling plane, each cooling tube having an inlet opening and a plurality of outlet openings.

[0030] Another example 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 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 start flowing cooling gas through the workpiece at a rate of approximately 300 slm or greater to reduce the t50 peak width of the workpiece upon expiration of the time interval, the cooling system having a plurality of cooling tubes arranged in a cooling plane, each cooling tube having an inlet opening and a plurality of outlet openings.

[0031] 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 exemplary 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.

[0032] Referring now to the accompanying drawings, Figure 1A 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 the top of the processing chamber 105, and another of the quartz windows 107 can at least partially define the 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.

[0033] As shown, the thermal processing system 100 may include an open position ( 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 the open position to allow the workpiece 120 to be positioned within the processing chamber 105. In some embodiments, the workpiece 120 can be at least partially supported by a workpiece support 130 configured to support the workpiece 120. In this manner, heat associated with emitting light into the lower quartz window 170 can be at least partially transferred to the workpiece 120 through the workpiece support 130. In some embodiments, the workpiece support 130 can be configured to rotate the workpiece 120 during the heat treatment process. For example, in some cases, the workpiece support 130 is rotatable. Additionally, once the workpiece 120 is positioned on the workpiece support 130, the door 110 can be moved to the 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.

[0034] 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.

[0035] The thermal treatment system 100 may include one or more heat sources 150 configured to heat the workpiece 120. The heat sources 150 may be disposed outside the processing chamber 105. For example, the heat sources 150 may be positioned above the processing chamber 105, below the processing chamber 105, or both above and below the processing chamber 105. The one or more heat sources 150 may be configured to emit light toward the workpiece 120 during a thermal treatment process, such as a rapid thermal processing or spike annealing process. More specifically, during the thermal treatment process, the heat sources 150 positioned above the processing chamber 105 may be configured to emit light toward the upper surface or sides of the workpiece 120, and the heat sources 150 positioned below the processing chamber 105 may be configured to emit light toward the lower surface or sides of the workpiece 120. The light emitted from the one or more heat sources 150 may increase the temperature of the workpiece 120. In some embodiments, the one or more heat sources 150 may increase the temperature of the workpiece 120 by greater than approximately 500° C. within a predetermined amount of time (e.g., less than 2 seconds).

[0036] 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.

[0037] 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).

[0038] 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.

[0039] According to an exemplary aspect of the present disclosure, the heat treatment system 100 includes a cooling system 200, as described in greater detail below, configured to flow cooling gas from a gas source through the workpiece 120 during heat treatment. A controller 190 can control the operation of the heat source 150 and the cooling system 200 during heat treatment (e.g., by varying the supply rate of cooling gas flowing through the workpiece 120) to reduce a 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. Furthermore, the controller 190 can control the operation of the workpiece support 130 to rotate the workpiece 120. For example, the controller 190 can control the operation of the workpiece support 130 to rotate the workpiece 120 during the heat treatment process, such as at least during operation of the cooling system 200.

[0040] In some embodiments, controller 190 (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 heat source 150 on or off during thermal processing, controlling the operation of cooling system 200, or other suitable operations, as described below.

[0041] Now turn Figure 2-4 , depicts example aspects of a cooling system 200 for a thermal processing system 100. More specifically, Figure 2 A perspective view of an example cooling system for a thermal processing system is depicted. Figure 3 A bottom-up view of the cooling tubes of an example cooling system for a thermal processing system is depicted. Figure 4 Depicted is a cross-sectional view of cooling tubes of an example cooling system of a thermal processing system.

[0042] like Figure 2 As shown, the cooling system 200 includes a plurality of cooling pipes 202 (e.g., a first cooling pipe 202A, a second cooling pipe 202B, a third cooling pipe 202C, and a fourth cooling pipe 202D) and a gas supply unit 210. The cooling pipes 202 are arranged in the same cooling plane P1 ( Figure 4 In some embodiments, the cooling plane P1 is parallel to the workpiece 120 or the workpiece support 130 ( Figure 1 ) of the workpiece plane P2 ( Figure 4 ). Each cooling tube 202 extends at least between an inlet end 204 (e.g., inlet ends 204A, 204B, 204C, 204D) and a closed end 206 (e.g., closed ends 206A, 206B, 206C, 206D). Each cooling tube 202 has a plurality of outlet openings or outlets 208 (e.g., outlets 208A, 208B, 208C, 208D) between the inlet end 204 and the closed end 206. The inlet end 204 of the cooling tube 202 is connected to a gas supply 210 such that cooling gas is supplied from the gas supply 210 into the inlet end 204 of the cooling tube 202 and is discharged from the cooling tube 202 through the outlet openings 208 toward the workpiece support 130, and thereby toward the workpiece supported thereon (e.g., workpiece 120). As will be described in greater detail below, in a preferred embodiment, the cooling system 200 has exactly four cooling tubes 202A, 202B, 202C, 202D.

[0043] In some cases, the inlet ends 204 of the cooling tubes 202 can be connected to the gas supply 210 via respective supply conduits 212 (e.g., supply conduits 212A, 212B, 212C, 212D) coupled between the gas supply 210 and the respective inlet ends 204 of the cooling tubes 202. However, in some cases, the supply conduits 212 are instead integrally formed with the cooling tubes 202 and define the inlet ends 204 of the cooling tubes 202. It should be understood that in some embodiments, the gas supply 210 is coupled to the cooling tubes 202 such that each of the cooling tubes 202 is provided with a substantially equal portion of the cooling gas flowing from the gas supply 210.

[0044] In one embodiment, the cooling tubes 202 can be configured to at least partially support each other. For example, the cooling tubes 202 can be coupled together by a support member 214 proximate the closed end 206 of the cooling tubes 202. As will be described in greater detail below, the cooling tubes 202 and the support member 214 can be configured such that the cooling device 200 does not radially overlap the center of the workpiece 120.

[0045] Now turn Figure 3 The cooling tubes 202 are configured to evenly distribute the cooling gas flowing therethrough across the workpiece. For example, the cooling tubes 202 can be evenly spaced. For example, in an embodiment having four cooling tubes, such as in the exemplary embodiment shown, directly adjacent cooling tubes of the four cooling tubes 202 are positioned perpendicular to one another. In some embodiments, each cooling tube 202 has the same number of outlet openings 208. Furthermore, in some aspects, the outlet openings 208 have the same cross-sectional area.

[0046] Each outlet opening 208 of the cooling tube 202 is radially spaced from a central axis C1 of a workpiece (e.g., the workpiece 120). Specifically, in some embodiments, each outlet opening 208 of the cooling tube 202 is spaced a different radial distance from the central axis C1 of the workpiece 120. For example, the radially innermost first outlet 208(1) of the outlet opening 208A of the first cooling tube 202A is spaced a first distance D1 from the central axis C1 of the workpiece 120, the radially innermost second outlet 208(2) of the outlet opening 208B of the second cooling tube 202B is spaced a second distance D2 from the central axis C1 of the workpiece 120, the radially innermost third outlet 208(3) of the outlet opening 208C of the third cooling tube 202C is spaced a third distance D3 from the central axis C1 of the workpiece 120, and the radially innermost fourth outlet 208(4) of the outlet opening 208D of the fourth cooling tube 202D is spaced a fourth distance D4 from the central axis C1 of the workpiece 120. The second distance D2 is greater than the first distance D1 , the third distance D3 is greater than the second distance D2 , and the fourth distance D4 is greater than the third distance D3 .

[0047] In one embodiment, the outlet openings 208 of the plurality of cooling tubes 202 are spaced outwardly from the first outlet 208(1) by increasingly smaller radial distances. Thus, the distance between the two radially innermost outlets 208 of the cooling tubes 202 is greater than the distance between the two radially outermost outlets 208 of the cooling tubes 202. In some embodiments, the spacing between the outlet openings 208 of each cooling tube 202A, 202B, 202C, 202D is the same for all cooling tubes 202. In some aspects, the spacing between the outlet openings 208 of the plurality of cooling tubes 202 is configured such that the outlet openings 208 form a spiral pattern. Additionally, in some aspects, the radially outermost outlet openings 208 are at or just beyond the outermost radius of the workpiece 120.

[0048] In addition, if Figure 3As shown, the cooling tube 202 may be spaced apart from the central axis C1 of the workpiece 120. For example, the closed end 206 of the cooling tube 202 may be radially spaced apart from the central axis C1 of the workpiece 120. Since one or both of the opening 208 and the closed end 206 of the cooling tube 202 are spaced apart from the central axis C1 of the workpiece 120, the central portion of the workpiece 120 is prevented from cooling at a different rate than the rest of the workpiece 120, for example, due to a higher concentration of cooling air flowing through the central portion of the workpiece 120 than through the outer portion of the workpiece 120.

[0049] like Figure 4 As shown, the outlet opening 208 can be formed in the cooling tube 202 so that the outlet opening 208 directs the cooling gas toward the workpiece. For example, the axis H1 of the outlet opening 208 can be positioned at an angle A1 relative to the cooling plane P1 of the cooling system 200. The angle A1 is generally configured so that the cooling gas flow from the interior 202INT of the cooling tube 202 is at least partially directed downward along the vertical direction V1 toward the workpiece plane P2. For example, the angle A1 can be between 20 degrees and 90 degrees, between 30 degrees and 70 degrees, between 40 degrees and 50 degrees, 45 degrees, or any other suitable angle.

[0050] Additionally, it should be understood that in some embodiments, the cooling tube 202 is constructed of quartz material. Thus, the cooling tube 202 can be fire-polished to reduce the number of particles generated by the cooling system 200 that may contaminate the workpiece during the annealing process.

[0051] Figure 5 An example temperature-time curve 300 of the thermal processing system 100 is depicted according to an example embodiment of the present disclosure. Figure 5As can be seen, after the first time period 310, a spike annealing process occurs during a second time period 320. 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 sources can be configured to cease emitting light once the temperature of the workpiece reaches or exceeds the temperature set point 334. The conventional spike annealing process 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 start flowing the cooling gas through the workpiece. Alternatively, the cooling system 200 can be controlled to start 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 less 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.

[0052] Figure 6 An example temperature-time curve 400 of the thermal processing system 100 is depicted according to an example embodiment of the present disclosure. Figure 6As 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 may be controlled to begin flowing the cooling gas through the workpiece when a second time interval (not shown) expires, wherein the second time interval may begin when the first time interval 420A expires and may 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.

[0053] Figure 7 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 7 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.

[0054] 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 support 130 in the processing chamber 105.

[0055] 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 .

[0056] 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 temperature indicating a temperature set point (e.g., Figure 5 The temperature set point may be within about 20% of the peak temperature of the heating profile associated with the spike annealing heating profile.

[0057] 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.

[0058] 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.

[0059] Figure 8 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 8 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.

[0060] 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 support 130 in the processing chamber 105.

[0061] 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 6 The expiration of the time interval 420A) described, for example, a time interval in the range of about 5 milliseconds to about 100 milliseconds.

[0062] 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 toward) the workpiece when the time interval expires.

[0063] Furthermore, at 608, method 600 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 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 cooling gas through workpiece 120 at a rate of approximately 300 slm or greater to reduce a t50 peak width of the workpiece.

[0064] 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, upon gaining an understanding of the foregoing, may readily make changes, variations, and equivalents to these embodiments. Accordingly, the scope of the present disclosure is intended to be illustrative rather than 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; and A cooling system is configured to flow cooling gas through the workpiece supported on the workpiece support, the cooling system comprising four cooling tubes arranged in a cooling plane, directly adjacent ones of the four cooling tubes being positioned perpendicular to one another, each cooling tube having an inlet opening and a plurality of outlet openings, an axis of each of the plurality of outlet openings of the cooling tube being angled relative to the cooling plane toward a workpiece plane defined by the workpiece.

2. The system of claim 1, wherein: The cooling system further includes a gas supply coupled to the inlet openings of the four cooling tubes to provide cooling gas from a gas source through the four cooling tubes and out of the plurality of outlet openings of the four cooling tubes, and The thermal processing system further includes a controller configured to control the heat source and the cooling system based at least in part on data indicating the temperature of the workpiece, providing a cooling gas flow into the processing chamber at a rate of 300 slm or greater to reduce the t50 peak width of the workpiece during thermal processing.

3. The system of claim 1, wherein: The plurality of outlet openings of the four cooling tubes are radially spaced from a central axis of the workpiece.

4. The system of claim 1, wherein: Each of the plurality of outlet openings of the four cooling tubes is at a different radial distance from the central axis of the workpiece.

5. The system of claim 4, wherein: A radial distance between adjacent ones of the plurality of outlet openings of each of the four cooling tubes decreases with increasing radial distance from a central axis of the workpiece.

6. The system of claim 1, wherein: The four cooling tubes are made of quartz material.

7. The system of claim 1, wherein: The four cooling tubes are spaced apart from a central axis of the workpiece.

8. The system of claim 1, wherein: The cooling plane is parallel to a workpiece plane of the workpiece.

9. A method for performing spike annealing rapid thermal processing, comprising: controlling, by one or more control devices, a heat source to initiate heating of a workpiece supported on a workpiece support in a processing chamber; receiving, by the one or more control devices, data indicative of a temperature of the workpiece from a temperature measurement system; monitoring, by the one or more control devices, a temperature of the workpiece relative to a temperature set point; controlling, by the one or more control devices, the heat source to cease heating the workpiece based at least in part on the workpiece reaching the temperature set point; and The one or more control devices control a cooling system to begin flowing cooling gas through the workpiece at a rate of 300 slm or greater to reduce a t50 peak width of the workpiece based at least in part on the workpiece reaching the temperature set point, the cooling system comprising four cooling tubes arranged in a cooling plane, each cooling tube extending radially toward a central axis, each cooling tube having an inlet opening and a plurality of outlet openings, each outlet opening of the four cooling tubes being at a different radial distance from the central axis.

10. The method of claim 9, wherein: The cooling system further includes a gas supply coupled to the inlet opening of each of the four cooling tubes to provide cooling gas from a gas source to pass through the four cooling tubes and out of the plurality of outlet openings of each of the four cooling tubes, the gas supply of the cooling system being controllable to vary a supply rate of the cooling gas.

11. The method of claim 9, wherein: The method also includes controlling, by the one or more control devices, the workpiece support to rotate the workpiece.

12. A cooling system for a rapid thermal processing system, comprising: four cooling tubes arranged in the cooling plane, each cooling tube extending radially toward the central axis, each cooling tube having an inlet opening and a plurality of outlet openings; and a gas supply portion coupled to the inlet openings of the four cooling tubes to provide cooling gas from a gas source through the four cooling tubes and out of the plurality of outlet openings of the four cooling tubes, Wherein, each of the plurality of outlet openings of the four cooling pipes is at a different radial distance from the central axis.

13. The system of claim 12, wherein: The plurality of outlet openings of the four cooling tubes are radially spaced from the central axis.

14. The system of claim 12, wherein: A radial distance between adjacent ones of the plurality of outlet openings of each of the four cooling tubes decreases with increasing radial distance from the central axis.

15. The system of claim 12, wherein: Each of the plurality of outlet openings of the four cooling tubes has a same cross-sectional area.

16. The system of claim 12, wherein: The four cooling tubes are made of quartz material.

17. The system of claim 12, wherein: Directly adjacent cooling tubes of the four cooling tubes are positioned perpendicular to each other.

18. The system of claim 12, wherein: An axis of each of the plurality of outlet openings of the four cooling tubes is angled relative to the cooling plane.

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