Heat Treatment Equipment

Abstract

To provide a heat treatment device capable of highly accurately measuring the temperature of a substrate in a chamber before reaching a stable temperature while suppressing a decrease in productivity of the substrate.SOLUTION: A heat treatment device 160 includes a chamber 161 that accommodates a semiconductor wafer W, a halogen heating portion 4 and a flash heating portion 5 that heat the semiconductor wafer W, a plurality of sensors S1 to S11 that measure parameters related to heating of the semiconductor wafer W, a storage portion 31 that stores data measured by the plurality of sensors S1 to S11, and a calculation portion 32 that predicts the output value of the first sensor among the plurality of sensors S1 to S11.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a heat treatment apparatus for heating thin precision electronic substrates (hereinafter simply referred to as "substrates") such as semiconductor wafers. [Background technology]

[0002] In heat treatment equipment that heats substrates, semiconductor wafers are typically processed in lots (a set of semiconductor wafers that are subjected to the same processing under the same conditions). In single-wafer heat treatment equipment, multiple semiconductor wafers that make up a lot are loaded into a chamber one by one and heat treated sequentially.

[0003] When a heat treatment apparatus that is out of operation starts processing a lot of semiconductor wafers or when processing conditions such as the processing temperature of the semiconductor wafers are changed, the temperature of the structures inside the chamber, such as the susceptor that holds the semiconductor wafers, may change.

[0004] If the temperature of the susceptor and other components in the chamber changes during the processing of multiple semiconductor wafers in a lot, the temperature history during processing will differ between the early and later semiconductor wafers in the lot, which will result in uneven quality for each semiconductor wafer.

[0005] To solve such problems, an apparatus such as that described in Patent Document 1 is disclosed. In the apparatus described in Patent Document 1, before starting processing of a lot, a dummy wafer that is not the target of processing is loaded into the chamber, supported by a susceptor, and heated under the same conditions as the lot to be processed, thereby allowing the temperature of the susceptor and other components within the chamber to reach a stable temperature during processing in advance. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2020-043288 Summary of the Invention [Problem to be solved by the invention]

[0007] In technologies that use such dummy wafers, a large number of dummy wafers must be processed before the temperature of the chamber interior stabilizes, resulting in reduced productivity. To improve productivity, it is necessary to know the substrate temperature even when the chamber interior has not yet reached a stable temperature.

[0008] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a heat treatment apparatus that can measure the temperature of a substrate in a chamber with high accuracy even before the stable temperature is reached, while suppressing a decrease in substrate productivity. [Means for solving the problem]

[0009] In order to solve the above problem, the invention of claim 1 provides a heating system including a chamber for accommodating a substrate, a heating unit for heating the substrate, and a plurality of sensors for measuring parameters related to the heating of the substrate. a control unit that controls the heating unit, a storage unit for storing data measured by the plurality of sensors; a calculation unit that performs calculation processing on the data stored in the storage unit, wherein the calculation unit includes a prediction unit that predicts the temperature of the substrate from an output value of any one of the plurality of sensors based on a learning model created in advance, and the prediction unit measured by a first sensor of the plurality of sensors Chronological data measured by a second sensor correlated with the first sensor; Chronological Data and and predicting the temperature of the substrate based on the output value of the first sensor derived from It is characterized by:

[0010] The invention of claim 2 provides the heat treatment apparatus according to claim 1, wherein the calculation unit: an output value of the first sensor at a predetermined time point based on an actual measurement value of the first sensor at a first past time point, an actual measurement value of the first sensor at a second past time point, and an actual measurement value of the second sensor at the first past time point; and the prediction unit predicts the temperature of the substrate at the predetermined time point. It is characterized by:

[0011] In addition, the invention of claim 3 , request In the heat treatment apparatus according to the invention of claim 2, the calculation unit multiplying each of the actual measurement value of the first sensor at the first past time point, the actual measurement value of the first sensor at the second past time point, and the actual measurement value of the second sensor at the first past time point by a fitness value that has been optimized with weighting according to the correlation between the first sensor and the second sensor, thereby deriving an output value of the first sensor at the predetermined time point; It is characterized by:

[0012] The invention of claim 4 is as follows: Any of claims 1 to 3In the heat treatment device according to the present invention, When a difference between the predicted temperature of the substrate and a target value set in a recipe exceeds a predetermined threshold, the control unit feedback controls the heating unit so that the predicted temperature of the substrate matches the target value. It is characterized by:

[0013] The invention of claim 5 is 1 of In the heat treatment device according to the present invention, The calculation unit creates the learning model using the temperature of the substrate measured by the thermocouple as training data. It is characterized by:

[0014] The invention of claim 6 is 1 of In the heat treatment device according to the present invention, The plurality of sensors include at least one selected from the group consisting of a lower radiation thermometer that measures the temperature of the lower surface of the substrate, an upper radiation thermometer that measures the temperature of the upper surface of the substrate, a temperature sensor that measures the temperature of a susceptor that holds the substrate, a temperature sensor that measures the temperature of an upper chamber window of the chamber, a temperature sensor that measures the temperature of a lower chamber window of the chamber, a temperature sensor that measures the temperature of an atmosphere inside the chamber, a temperature sensor that measures the temperature of a side surface of the chamber, an ammeter that measures the amount of power supplied to the heating unit, a light intensity sensor that measures the amount of light irradiated from the heating unit, and a flow meter that measures the flow rate of a process gas supplied into the chamber. It is characterized by:

[0015] The invention of claim 7 provides the heat treatment apparatus according to the invention of claim 6, The second sensor is one selected from the group consisting of a temperature sensor that measures the temperature of the susceptor, a temperature sensor that measures the temperature of the upper chamber window, a temperature sensor that measures the temperature of the lower chamber window, a temperature sensor that measures the temperature of the atmosphere in the chamber, and a temperature sensor that measures the temperature of the side surface of the chamber. It is characterized by: [Effects of the Invention]

[0016] Claim 1 Request from According to the invention of claim 7, the temperature measured by the first sensor Chronological data and the data measured by the second sensor Chronological Data and to predict the temperature of the substrate based on the output value of the first sensor derived from The temperature of the substrate in the chamber before it reaches a stable temperature can be measured with high accuracy while suppressing a decrease in substrate productivity. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a cross-sectional view schematically showing the configuration of a heat treatment apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view showing the overall appearance of the holding portion. [Figure 3] FIG. [Figure 4] FIG. 2 is a cross-sectional view of a susceptor. [Figure 5] FIG. [Figure 6] FIG. [Figure 7] FIG. 2 is a plan view showing the arrangement of a plurality of halogen lamps HL in the halogen heating section. [Figure 8]FIG. 2 is a functional block diagram illustrating an electrical configuration of a heat treatment apparatus including a calculation unit. [Figure 9] 10 is a flowchart showing the processing steps for creating a learning model. [Figure 10] FIG. 10 is a diagram showing the relationship between the predicted output value of a first sensor, the actual measured value of a second sensor, and the fitness value. [Figure 11] 10 is a flowchart showing the processing procedure for a semiconductor wafer W using a learning model. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments will be described with reference to the accompanying drawings. In the following embodiments, detailed features will be shown for the purpose of explaining the technology, but these are merely examples and are not necessarily essential features for enabling the embodiments to be implemented.

[0021] The drawings are schematic, and for the sake of convenience, components may be omitted or simplified as appropriate. Furthermore, the relative sizes and positions of components shown in different drawings are not necessarily accurately depicted and may be changed as appropriate. Hatching may also be used in drawings such as plan views that are not cross-sectional views to facilitate understanding of the embodiments.

[0022] In the following description, the same components are denoted by the same reference numerals, and their names and functions are also the same. Therefore, detailed descriptions of them may be omitted to avoid duplication.

[0023] Furthermore, in the following description, when a certain component is described as "comprising," "including," or "having," unless otherwise specified, this is not an exclusive expression that excludes the presence of other components.

[0024] Furthermore, in the following description, even if ordinal numbers such as "first" or "second" are used, these terms are used for convenience to facilitate understanding of the contents of the embodiments, and are not limited to the ordering that may result from these ordinal numbers.

[0025] Furthermore, in the following description, expressions indicating relative or absolute positional relationships, such as "in one direction," "along one direction," "parallel," "orthogonal," "center," "concentric," or "coaxial," unless otherwise specified, include cases where the positional relationship is strictly indicated and cases where the angle or distance is displaced within a tolerance or within a range where equivalent functionality is obtained.

[0026] Furthermore, in the following description, expressions indicating an equal state, such as "same," "equal," "uniform," or "homogeneous," unless otherwise specified, include cases indicating an exact equal state, as well as cases where there is a difference within a tolerance or within a range where the same level of functionality is obtained.

[0027] Furthermore, in the following description, terms that indicate specific positions or directions, such as "top," "bottom," "left," "right," "side," "bottom," "front," or "back," may be used; however, these terms are used for convenience to facilitate understanding of the contents of the embodiments, and have no relation to the positions or directions when actually implemented.

[0028] Furthermore, in the following explanation, when "the upper surface of ..." or "the lower surface of ..." is written, it includes not only the upper surface or lower surface of the target component itself, but also a state in which another component is formed on the upper surface or lower surface of the target component. In other words, for example, when it is written as "Part B provided on the upper surface of Part A," it does not prevent another component "Part C" from being interposed between Part A and Part B.

[0029] First Embodiment The heat treatment apparatus according to this embodiment will be described below.

[0030] <Configuration of Heat Treatment Device 160> FIG. 1 is a cross-sectional view schematically showing the configuration of a heat treatment apparatus 160 according to this embodiment.

[0031] As shown in FIG. 1, the heat treatment apparatus 160 of this embodiment is an apparatus that heats a disk-shaped semiconductor wafer W as a substrate by irradiating the semiconductor wafer W with light.

[0032] The size of the semiconductor wafer W to be processed is not particularly limited, but is, for example, φ300 mm or φ450 mm (φ300 mm in this embodiment).

[0033] The heat treatment apparatus 160 includes a chamber 161 that accommodates a semiconductor wafer W, a flash heating unit 5 incorporating multiple flash lamps FL as a main heating unit, and a halogen heating unit 4 incorporating multiple halogen lamps HL as a preheating unit. The flash heating unit 5 is provided above the chamber 161, and the halogen heating unit 4 is provided below it. The heat treatment apparatus 160 also includes a control unit 3 that controls the halogen heating unit 4, the flash heating unit 5, and the various operating mechanisms provided in the chamber 161 to perform heat treatment on the semiconductor wafer W. In this embodiment, the control unit 3 includes a calculation unit 32 that predicts the output value of a first sensor (any of S1 to S11) described below. In this embodiment, the halogen heating unit 4 includes multiple halogen lamps HL, but arc lamps or light-emitting diodes (LEDs) may be used instead of the halogen lamps HL. With the above-described configuration, the semiconductor wafer W is heated while housed in the chamber.

[0034] The plurality of flash lamps FL emit flashes of light to heat the semiconductor wafer W. The plurality of halogen lamps HL heat the semiconductor wafer W continuously.

[0035] The heat treatment apparatus 160 also includes, inside the chamber 161, a holder 7 that holds the semiconductor wafer W in a horizontal position, and a transfer mechanism 10 that transfers the semiconductor wafer W between the holder 7 and the outside of the apparatus.

[0036] The chamber 161 is closed by an upper chamber window 63 made of quartz attached to the top surface of the chamber housing (chamber side portion 61).

[0037] The upper chamber window 63, which forms the ceiling of the chamber 161, is a disk-shaped member made of quartz and functions as a quartz window (light-transmitting window) that transmits light emitted from the flash heating section 5 into the chamber 161.

[0038] In addition, the lower chamber window 64 that forms the floor of the chamber 161 is also a disk-shaped member made of quartz, and functions as a quartz window (light-transmitting window) that transmits light from the halogen heating unit 4 into the chamber 161.

[0039] Furthermore, a reflecting ring 68 is attached to the upper part of the inner side surface of the chamber side part 61, and a reflecting ring 69 is attached to the lower part. Both the reflecting ring 68 and the reflecting ring 69 are formed in an annular shape.

[0040] The upper reflecting ring 68 is attached by fitting it from the top side of the chamber side part 61. On the other hand, the lower reflecting ring 69 is attached by fitting it from the bottom side of the chamber side part 61 and fastening it with screws (not shown). In other words, both the reflecting ring 68 and the reflecting ring 69 are detachably attached to the chamber side part 61.

[0041] The inner space of the chamber 161, that is, the space surrounded by the upper chamber window 63, the chamber housing (chamber side portion 61), and the reflecting ring 68, is defined as a heat treatment space 65.

[0042] By attaching the reflecting ring 68 and the reflecting ring 69 to the chamber side part 61, a recess 62 is formed on the inner surface of the chamber 161. In other words, the recess 62 is formed by the central part of the inner surface of the chamber side part 61 where the reflecting ring 68 and the reflecting ring 69 are not attached, the lower end surface of the reflecting ring 68, and the upper end surface of the reflecting ring 69.

[0043] The recess 62 is formed in a circular ring shape along the horizontal direction on the inner surface of the chamber 161, and surrounds the holder 7 that holds the semiconductor wafer W. The chamber side portion 61 and the reflecting ring 68 and the reflecting ring 69 are made of a metal material (e.g., stainless steel) that has excellent strength and heat resistance.

[0044] Furthermore, a transfer opening (furnace port) 66 is formed in the chamber housing (chamber side portion 61) for carrying the semiconductor wafer W into and out of the chamber 161. The transfer opening 66 can be opened and closed by a gate valve 162. The transfer opening 66 is connected to the outer circumferential surface of the recess 62.

[0045] Therefore, when the gate valve 162 opens the transfer opening 66, the semiconductor wafer W can be carried into and out of the heat treatment space 65 through the transfer opening 66 and the recess 62. When the gate valve 162 closes the transfer opening 66, the heat treatment space 65 in the chamber 161 becomes an airtight space.

[0046] An upper radiation thermometer 25 and a lower radiation thermometer 20 are attached to the respective positions of through holes 61a, 61b on the outer surface of the chamber side portion 61. The through hole 61a is a cylindrical hole for guiding infrared light radiated from the upper surface of a semiconductor wafer W held on a susceptor 74 (described later) to the upper radiation thermometer 25. The through hole 61b is a cylindrical hole for guiding infrared light radiated from the lower surface of the semiconductor wafer W held on the susceptor 74 (described later) to the lower radiation thermometer 20. The through holes 61a, 61b are provided at an angle with respect to the horizontal direction so that the axes of the through holes intersect with the main surface of the semiconductor wafer W held on the susceptor 74. A transparent window 26 made of calcium fluoride material that transmits infrared light in a wavelength range that can be measured by the upper radiation thermometer 25 is attached to the end of the through hole 61a facing the heat treatment space 65. Furthermore, a transparent window 21 made of barium fluoride material that transmits infrared light in the wavelength range that can be measured by the lower radiation thermometer 20 is attached to the end of the through hole 61b facing the heat treatment space 65.

[0047] The upper radiation thermometer 25 is installed diagonally above the semiconductor wafer W held on the susceptor 74, and measures the temperature of the upper surface by receiving infrared light emitted from the upper surface of the semiconductor wafer W. The infrared sensor 29 provided in the upper radiation thermometer 25 has an InSb (indium antimonide) optical element so as to be able to respond to the sudden temperature change on the upper surface of the semiconductor wafer W at the moment when the flash light is irradiated.

[0048] On the other hand, the lower radiation thermometer 20 is installed diagonally below the semiconductor wafer W held on the susceptor 74, and measures the temperature of the lower surface by receiving infrared light emitted from the lower surface of the semiconductor wafer W. The lower radiation thermometer 20 is equipped with an infrared sensor 24, and measures the temperature of the lower surface of the semiconductor wafer W.

[0049] The upper radiation thermometer 25 and the lower radiation thermometer 20 as described above measure parameters related to the heating of the semiconductor wafer W. The heat treatment apparatus 160 also includes a plurality of sensors that measure parameters related to the heating of the semiconductor wafer W. For example, temperature sensors 91, 92, 93, 94, and 95 are installed in the chamber 161. Of the temperature sensors 91, 92, 93, 94, and 95, the temperature sensor 91 measures the susceptor 74, the temperature sensor 92 measures the upper chamber window 63, the temperature sensor 93 measures the lower chamber window 64, the temperature sensor 94 measures the atmosphere inside the chamber, and the temperature sensor 95 measures the side surface of the chamber 161.

[0050] Furthermore, gas supply holes 81 are formed in the upper part of the inner wall of the chamber 161 to supply processing gas to the heat treatment space 65. The gas supply holes 81 are formed at a position above the recessed portion 62, and may be provided in the reflecting ring 68. The gas supply holes 81 are connected to a gas supply pipe 83 via a buffer space 82 formed in an annular shape inside the side wall of the chamber 161.

[0051] The gas supply pipe 83 is connected to a process gas supply source 85. A valve 84 is inserted in the gas supply pipe 83. When the valve 84 is opened, the process gas is supplied from the process gas supply source 85 to the buffer space 82. A flow meter 98 is connected downstream of the valve 84 and measures the flow rate of the process gas passing through the valve 84. The flow meter 98 also functions as a sensor for measuring parameters related to the heating of the semiconductor wafer W.

[0052] The processing gas that has flowed into the buffer space 82 spreads within the buffer space 82, which has a smaller fluid resistance than the gas supply holes 81, and is supplied from the gas supply holes 81 into the heat treatment space 65. The processing gas may be an inert gas such as nitrogen (N2), or a reactive gas such as hydrogen (H2) or ammonia (NH3) (nitrogen in this embodiment).

[0053] Meanwhile, a gas exhaust hole 86 is formed in the lower part of the inner wall of the chamber 161 to exhaust gas from the heat treatment space 65. The gas exhaust hole 86 is formed at a position lower than the recess 62, and may be provided in the reflecting ring 69. The gas exhaust hole 86 is connected to a gas exhaust pipe 88 via a buffer space 87 formed in an annular shape inside the side wall of the chamber 161. The gas exhaust pipe 88 is connected to an exhaust mechanism 190. A valve 89 is inserted in the path of the gas exhaust pipe 88. When the valve 89 is opened, the gas in the heat treatment space 65 is exhausted from the gas exhaust hole 86 through the buffer space 87 to the gas exhaust pipe 88.

[0054] The gas supply holes 81 and the gas exhaust holes 86 may be provided in multiple numbers along the circumferential direction of the chamber 161, or may be slit-shaped. The process gas supply source 85 and the exhaust mechanism 190 may be mechanisms provided in the heat treatment device 160, or may be utilities of a factory where the heat treatment device 160 is installed.

[0055] A gas exhaust pipe 191 for discharging gas from the heat treatment space 65 is also connected to the tip of the transfer opening 66. The gas exhaust pipe 191 is connected to an exhaust mechanism 190 via a valve 192. By opening the valve 192, the gas in the chamber 161 is exhausted through the transfer opening 66.

[0056] 2 is a perspective view showing the overall appearance of the holder 7. The holder 7 is configured to include a base ring 71, a connecting portion 72, and a susceptor 74. The base ring 71, the connecting portion 72, and the susceptor 74 are all made of quartz. In other words, the entire holder 7 is made of quartz.

[0057] The base ring 71 is an arc-shaped quartz member with a portion missing from the annular shape. This missing portion is provided to prevent interference between the base ring 71 and a transfer arm 11 of the transfer mechanism 10, which will be described later. The base ring 71 is placed on the bottom surface of the recess 62, and is supported by the side surface of the chamber 161 (see FIG. 3). A plurality of connecting portions 72 (four in this embodiment) are erected on the upper surface of the base ring 71 along the circumferential direction of the annular shape. The connecting portions 72 are also quartz members, and are fixed to the base ring 71 by welding.

[0058] The susceptor 74 is supported from below by four connecting portions 72 provided on the base ring 71. Fig. 3 is a plan view of the susceptor 74. Fig. 4 is a cross-sectional view of the susceptor 74.

[0059] The susceptor 74 includes a holding plate 75, a guide ring 76, and a plurality of support pins 77. The holding plate 75 is a substantially circular, flat member made of quartz. The diameter of the holding plate 75 is larger than the diameter of the semiconductor wafer W. That is, the holding plate 75 has a larger planar size than the semiconductor wafer W.

[0060] A guide ring 76 is installed on the periphery of the upper surface of the holding plate 75. The guide ring 76 is an annular member having an inner diameter larger than the diameter of the semiconductor wafer W. For example, if the diameter of the semiconductor wafer W is φ300 mm, the inner diameter of the guide ring 76 is φ320 mm.

[0061] The inner periphery of the guide ring 76 is formed into a tapered surface that widens upward from the holding plate 75. The guide ring 76 is made of quartz, the same as the holding plate 75.

[0062] The guide ring 76 may be welded to the upper surface of the holding plate 75, or may be fixed to the holding plate 75 by a separately processed pin or the like. Alternatively, the holding plate 75 and the guide ring 76 may be processed as an integrated member.

[0063] An area of ​​the upper surface of the holding plate 75 that is inside the guide ring 76 is a flat holding surface 75a that holds the semiconductor wafer W. A plurality of support pins 77 are provided on the holding surface 75a of the holding plate 75. In this embodiment, a total of 12 support pins 77 are provided in an annular shape at intervals of 30° along a circumference concentric with the outer circumferential circle of the holding surface 75a (the inner circumferential circle of the guide ring 76).

[0064] The diameter of the circle on which the 12 support pins 77 are arranged (the distance between opposing support pins 77) is smaller than the diameter of the semiconductor wafer W, and if the diameter of the semiconductor wafer W is φ300 mm, it is φ210 mm to φ280 mm. Three or more support pins 77 are provided. Each support pin 77 is made of quartz.

[0065] The plurality of support pins 77 may be provided on the upper surface of the holding plate 75 by welding, or may be machined integrally with the holding plate 75 .

[0066] Returning to FIG. 2, four connecting portions 72 erected on the base ring 71 are fixed to the peripheral edge of the holding plate 75 of the susceptor 74 by welding. That is, the susceptor 74 and the base ring 71 are fixedly connected by the connecting portions 72. The base ring 71 of the holding portion 7 is supported on the side surface of the chamber 161, and the holding portion 7 is thereby attached to the chamber 161. When the holding portion 7 is attached to the chamber 161, the holding plate 75 of the susceptor 74 is in a horizontal position (a position in which the normal line coincides with the vertical direction). That is, the holding surface 75a of the holding plate 75 is a horizontal plane.

[0067] The semiconductor wafer W carried into the chamber 161 is placed and held in a horizontal position on the upper side of the susceptor 74 of the holder 7 attached to the chamber 161. At this time, the semiconductor wafer W is supported by twelve support pins 77 erected on the holding plate 75, and is supported from below by the susceptor 74. More precisely, the upper ends of the twelve support pins 77 contact the lower surface (rear surface) of the semiconductor wafer W to support the semiconductor wafer W.

[0068] The twelve support pins 77 have a uniform height (the distance from the upper end of the support pin 77 to the holding surface 75a of the holding plate 75), so that the twelve support pins 77 can support the semiconductor wafer W in a horizontal position.

[0069] Furthermore, the semiconductor wafer W is supported by a plurality of support pins 77 at a predetermined distance from the holding surface 75a of the holding plate 75. The thickness of the guide ring 76 is greater than the height of the support pins 77. Therefore, the guide ring 76 prevents the semiconductor wafer W supported by the plurality of support pins 77 from shifting in the horizontal direction.

[0070] 2 and 3, an opening 78 is formed in the holding plate 75 of the susceptor 74, penetrating vertically. The opening 78 is provided so that the lower radiation thermometer 20 can receive radiant light (infrared light) emitted from the lower surface (rear surface) of the semiconductor wafer W. That is, the lower radiation thermometer 20 receives the light radiated from the lower surface (rear surface) of the semiconductor wafer W through the opening 78 and the transparent window 21 (attached to the through-hole 61b) of the chamber housing (chamber side portion 61), thereby measuring the temperature of the semiconductor wafer W.

[0071] Furthermore, the holding plate 75 of the susceptor 74 is provided with four through holes 79 through which lift pins 12 of the transfer mechanism 10 (described later) penetrate to transfer the semiconductor wafer W.

[0072] Fig. 5 is a plan view of the transfer mechanism 10. Fig. 6 is a side view of the transfer mechanism 10. The transfer mechanism 10 includes two transfer arms 11. The transfer arms 11 have an arc shape that fits along the generally annular recess 62.

[0073] Two lift pins 12 are erected on each transfer arm 11. The transfer arms 11 and the lift pins 12 are made of quartz. Each transfer arm 11 can be rotated by a horizontal movement mechanism 13. The horizontal movement mechanism 13 moves the pair of transfer arms 11 horizontally between a transfer operation position (position indicated by a solid line in FIG. 5) where the pair of transfer arms 11 transfer the semiconductor wafer W to the holder 7 and a retracted position (position indicated by a two-dot chain line in FIG. 5) where the pair of transfer arms 11 do not overlap the semiconductor wafer W held by the holder 7 in a plan view.

[0074] The horizontal movement mechanism 13 may be one that rotates each transfer arm 11 using an individual motor, or one that uses a link mechanism to rotate a pair of transfer arms 11 in unison using a single motor.

[0075] Furthermore, the pair of transfer arms 11 are moved up and down together with the horizontal movement mechanism 13 by the lifting mechanism 14. When the lifting mechanism 14 raises the pair of transfer arms 11 to the transfer operation position, a total of four lift pins 12 pass through through holes 79 (see FIGS. 2 and 3) formed in the susceptor 74, and the upper ends of the lift pins 12 protrude from the upper surface of the susceptor 74. Meanwhile, when the lifting mechanism 14 lowers the pair of transfer arms 11 to the transfer operation position to remove the lift pins 12 from the through holes 79, and the horizontal movement mechanism 13 moves the pair of transfer arms 11 to open them, each transfer arm 11 moves to the retracted position.

[0076] The retracted position of the pair of transfer arms 11 is directly above the base ring 71 of the holder 7. Since the base ring 71 is placed on the bottom surface of the recess 62, the retracted position of the transfer arms 11 is inside the recess 62. An exhaust mechanism (not shown) is also provided near the location where the drive parts (horizontal movement mechanism 13 and lifting mechanism 14) of the transfer mechanism 10 are provided, and is configured to exhaust the atmosphere around the drive parts of the transfer mechanism 10 to the outside of the chamber 161.

[0077] Returning to Figure 1, the flash heating unit 5 provided above the chamber 161 is configured to include a light source consisting of multiple (30 in this embodiment) xenon flash lamps FL inside a housing 51, and a reflector 52 provided to cover the light source from above.

[0078] A lamp light emission window 53 is attached to the bottom of the housing 51 of the flash heating unit 5. The lamp light emission window 53, which forms the floor of the flash heating unit 5, is a plate-shaped quartz window made of quartz. When the flash heating unit 5 is installed above the chamber 161, the lamp light emission window 53 faces the upper chamber window 63. The flash lamps FL emit flash light from above the chamber 161 through the lamp light emission window 53 and the upper chamber window 63 into the heat treatment space 65. A light intensity sensor 96 is attached to the lamp light emission window 53, and the light intensity sensor 96 detects the amount of light emitted from the flash lamps FL. The light intensity sensor 96 may also function as a sensor for measuring parameters related to the heating of the semiconductor wafer W.

[0079] The multiple flash lamps FL are each a rod-shaped lamp having a long cylindrical shape, and are arranged in a plane so that their longitudinal directions are parallel to each other (i.e., along the horizontal direction) along the main surface (surface) of the semiconductor wafer W held by the holder 7. Therefore, the plane formed by the arrangement of the flash lamps FL is also a horizontal plane.

[0080] The flash lamp FL comprises a rod-shaped glass tube (discharge tube) filled with xenon gas and having an anode and a cathode connected to a capacitor at both ends, and a trigger electrode attached to the outer surface of the glass tube.

[0081] Xenon gas is an electrical insulator, so even if a charge is stored in the capacitor, no electricity flows through the glass tube under normal conditions. However, when a high voltage is applied to the trigger electrode to break down the insulation, the electricity stored in the capacitor flows instantaneously through the glass tube, exciting the xenon atoms or molecules and causing light to be emitted.

[0082] In such flash lamps FL, electrostatic energy stored in a capacitor is converted into extremely short light pulses of 0.1 to 100 milliseconds, which allows them to emit much stronger light than continuous light sources such as halogen lamps HL. In other words, flash lamps FL are pulsed lamps that emit light instantaneously for an extremely short period of time, less than one second. The light emission time of flash lamps FL can be adjusted by the coil constant of the lamp power supply that supplies power to the flash lamp FL.

[0083] Furthermore, reflector 52 is provided above the multiple flash lamps FL so as to cover them entirely. The basic function of reflector 52 is to reflect the flash light emitted from the multiple flash lamps FL toward the heat treatment space 65. Reflector 52 is made of an aluminum alloy plate, and its top surface (the surface facing the flash lamps FL) is roughened by blasting.

[0084] The halogen heating unit 4, which is provided below the chamber 161, has a plurality of halogen lamps HL (40 in this embodiment) built into the inside of the housing 41. The halogen heating unit 4 heats the semiconductor wafer W by irradiating light from the plurality of halogen lamps HL from below the chamber 161 through the lower chamber window 64 into the heat treatment space 65. A light intensity sensor 97 is attached to the top of the housing 41, and the light intensity sensor 97 detects the amount of light irradiated from the halogen lamps HL. The light intensity sensor 97 may also function as a sensor for measuring parameters related to the heating of the semiconductor wafer W.

[0085] 7 is a plan view showing the arrangement of multiple halogen lamps HL in the halogen heating unit 4. The 40 halogen lamps HL are arranged in two rows, upper and lower. Twenty halogen lamps HL are arranged in the upper row, which is closer to the holder 7, and another 20 halogen lamps HL are arranged in the lower row, which is farther from the holder 7 than the upper row.

[0086] Each halogen lamp HL is a rod-shaped lamp having a long cylindrical shape. The 20 halogen lamps HL in both the upper and lower rows are arranged so that their longitudinal directions are parallel to each other (i.e., along the horizontal direction) along the main surface (front surface) of the semiconductor wafer W held by the holder 7. Therefore, the plane formed by the arrangement of the halogen lamps HL in both the upper and lower rows is a horizontal plane.

[0087] 7, the halogen lamps HL are arranged more densely in the region facing the periphery of the semiconductor wafer W held by the holder 7 on both the upper and lower tiers than in the region facing the center of the semiconductor wafer W. That is, on both the upper and lower tiers, the halogen lamps HL are arranged at a shorter pitch in the periphery of the lamp arrangement than in the center. This allows a greater amount of light to be irradiated onto the periphery of the semiconductor wafer W, which is prone to temperature drop during heating due to light irradiation from the halogen heating unit 4.

[0088] 1, a voltage is applied to each of the multiple halogen lamps HL from a power supply unit 49, causing the halogen lamp HL to emit light. The power supply unit 49 individually adjusts the power supplied to each of the multiple halogen lamps HL under the control of the control unit 3. In other words, the power supply unit 49 can individually adjust the emission intensity of each of the multiple halogen lamps HL arranged in the halogen heating unit 4.

[0089] The lamp group consisting of the halogen lamps HL on the upper row and the lamp group consisting of the halogen lamps HL on the lower row are arranged so as to intersect in a grid pattern. That is, a total of 40 halogen lamps HL are arranged so that the longitudinal direction of the 20 halogen lamps HL arranged on the upper row and the longitudinal direction of the 20 halogen lamps HL arranged on the lower row are perpendicular to each other.

[0090] The halogen lamp HL is a filament-type light source that emits light by passing electricity through a filament placed inside a glass tube, causing it to become incandescent. The glass tube is filled with an inert gas such as nitrogen or argon, to which a small amount of halogen element (iodine, bromine, etc.) has been added. By adding halogen element, it is possible to set the filament temperature to a high temperature while suppressing filament breakage.

[0091] Therefore, halogen lamps HL have the characteristics of having a longer lifespan than ordinary incandescent light bulbs and being able to continuously irradiate strong light. In other words, halogen lamps HL are continuously lit lamps that emit light for at least one second or more. Furthermore, because the halogen lamps HL are rod-shaped lamps, they have a long lifespan, and arranging the halogen lamps HL horizontally improves the radiation efficiency toward the semiconductor wafer W above. Also, within the housing 41 of the halogen heating unit 4, a reflector 43 is provided below the two-tiered halogen lamps HL (FIG. 3). The reflector 43 reflects the light emitted from the multiple halogen lamps HL toward the heat treatment space 65.

[0092] The heat treatment apparatus 160 is also equipped with various cooling structures to prevent excessive temperature rises in the halogen heating unit 4, flash heating unit 5, and chamber 161 due to the thermal energy generated by the halogen lamps HL and flash lamps FL during heat treatment of the semiconductor wafer W. For example, a water-cooled pipe (not shown) is provided in the wall of the chamber 161. The halogen heating unit 4 and flash heating unit 5 have an air-cooled structure that dissipates heat by creating a gas flow inside. Air is also supplied to the gap between the upper chamber window 63 and the lamp light emission window 53 to cool the flash heating unit 5 and upper chamber window 63.

[0093] Next, a description will be given of the processing operation in the heat treatment apparatus 160. The processing procedure for the semiconductor wafer W described below progresses as the control unit 3 controls each operating mechanism of the heat treatment apparatus 160.

[0094] First, prior to processing of semiconductor wafers W, valve 84 for supplying gas is opened, and exhaust valve 89 is also opened to start supplying and exhausting gas to and from chamber 161. When valve 84 is opened, nitrogen gas is supplied to heat treatment space 65 through gas supply hole 81. Furthermore, when valve 89 is opened, gas within chamber 161 is exhausted through gas exhaust hole 86. As a result, nitrogen gas supplied from the upper part of heat treatment space 65 within chamber 161 flows downward and is exhausted from the lower part of heat treatment space 65.

[0095] Furthermore, by opening the valve 192, the gas inside the chamber 161 is also exhausted from the transfer opening 66. Furthermore, an exhaust mechanism (not shown) also exhausts the atmosphere around the drive unit of the transfer mechanism 10. Note that, during the heat treatment of the semiconductor wafer W in the heat treatment device 160, nitrogen gas is continuously supplied to the heat treatment space 65, and the supply amount is changed as appropriate depending on the treatment process.

[0096] Next, the gate valve 162 is opened to open the transfer opening 66, and a semiconductor wafer W to be processed is carried into the heat treatment space 65 in the chamber 161 by a transfer robot outside the apparatus through the transfer opening 66. At this time, there is a risk that the atmosphere outside the apparatus may be drawn in as the semiconductor wafer W is carried in, but since nitrogen gas is continuously supplied to the chamber 161, the nitrogen gas flows out from the transfer opening 66, making it possible to minimize the drawing in of such external atmosphere.

[0097] The semiconductor wafer W carried in by the transfer robot advances to a position directly above the holder 7 and stops there. Then, the pair of transfer arms 11 of the transfer mechanism 10 move horizontally from the retracted position to the transfer operation position and rise, causing the lift pins 12 to pass through the through holes 79 and protrude from the upper surface of the holding plate 75 of the susceptor 74 to receive the semiconductor wafer W. At this time, the lift pins 12 rise to a position higher than the upper ends of the support pins 77.

[0098] After the semiconductor wafer W is placed on the lift pins 12, the transfer robot exits the heat treatment space 65, and the transfer opening 66 is closed by the gate valve 162. Then, the pair of transfer arms 11 descend, transferring the semiconductor wafer W from the transfer mechanism 10 to the susceptor 74 of the holder 7, where it is held from below in a horizontal position. The semiconductor wafer W is supported by a plurality of support pins 77 erected on the holding plate 75 and held on the susceptor 74. The semiconductor wafer W is held on the holder 7 with its front surface, which is the surface to be processed, facing upward. A predetermined gap is formed between the back surface (the main surface opposite to the front surface) of the semiconductor wafer W supported by the plurality of support pins 77 and the holding surface 75a of the holding plate 75. The pair of transfer arms 11, which have descended to below the susceptor 74, are retracted to a retracted position, i.e., inside the recess 62, by the horizontal movement mechanism 13.

[0099] After the semiconductor wafer W is held from below in a horizontal position by the susceptor 74 of the holder 7, which is made of quartz, the 40 halogen lamps HL of the halogen heating unit 4 are turned on all at once to begin preheating (assisted heating). The halogen light emitted from the halogen lamps HL passes through the lower chamber window 64 and the susceptor 74, both of which are made of quartz, and is irradiated onto the underside of the semiconductor wafer W. The semiconductor wafer W is preheated by being irradiated with light from the halogen lamps HL, and its temperature rises. Note that the transfer arm 11 of the transfer mechanism 10 is retracted inside the recess 62, so it does not interfere with heating by the halogen lamps HL.

[0100] The temperature of the semiconductor wafer W, which is heated by the light irradiation from the halogen lamps HL, is measured by the lower radiation thermometer 20. The measured temperature of the semiconductor wafer W is transmitted to the control unit 3. The control unit 3 controls the output of the halogen lamps HL while monitoring whether the temperature of the semiconductor wafer W, which is heated by the light irradiation from the halogen lamps HL, has reached a predetermined preheating temperature. That is, the control unit 3 feedback-controls the output of the halogen lamps HL based on the value measured by the lower radiation thermometer 20 so that the temperature of the semiconductor wafer W reaches the preheating temperature.

[0101] After the temperature of the semiconductor wafer W reaches the preheating temperature, the control unit 3 temporarily maintains the semiconductor wafer W at that preheating temperature. Specifically, when the temperature of the semiconductor wafer W measured by the lower radiation thermometer 20 reaches the preheating temperature, the control unit 3 adjusts the output of the halogen lamps HL to maintain the temperature of the semiconductor wafer W at approximately the preheating temperature.

[0102] By performing preheating using the halogen lamps HL in this manner, the temperature of the entire semiconductor wafer W is uniformly raised to the preheating temperature. During preheating using the halogen lamps HL, the temperature of the peripheral portion of the semiconductor wafer W, where heat dissipation is more likely, tends to be lower than that of the central portion, but the arrangement density of the halogen lamps HL in the halogen heating unit 4 is higher in the region facing the peripheral portion of the semiconductor wafer W than in the region facing the central portion. As a result, a greater amount of light is irradiated onto the peripheral portion of the semiconductor wafer W, where heat dissipation is more likely, and the in-plane temperature distribution of the semiconductor wafer W during the preheating stage can be made uniform.

[0103] When a predetermined time has elapsed since the temperature of the semiconductor wafer W reached the preheating temperature, the flash lamps FL of the flash heating unit 5 irradiate the surface of the semiconductor wafer W held on the susceptor 74 with flash light. At this time, part of the flash light emitted from the flash lamps FL heads directly into the chamber 161, and the other part is reflected by the reflector 52 and then heads into the chamber 161, and the semiconductor wafer W is flash-heated by the irradiation of these flash lights.

[0104] Flash heating is performed by irradiating a flash of light (flash of light) from flash lamps FL, which can raise the surface temperature of the semiconductor wafer W in a short time. That is, the flash of light irradiated from the flash lamps FL is an extremely short, intense flash of light with an irradiation time of approximately 0.1 milliseconds to 100 milliseconds, in which electrostatic energy previously stored in a capacitor is converted into an extremely short light pulse. The surface temperature of the semiconductor wafer W flash-heated by the irradiation of the flash of light from the flash lamps FL instantaneously rises to a processing temperature of 1000°C or higher and then rapidly drops.

[0105] After the flash heating process is completed, the halogen lamps HL are turned off after a predetermined time has elapsed. This causes the temperature of the semiconductor wafer W to rapidly decrease from the preheating temperature. The temperature of the semiconductor wafer W during this decrease is measured by the lower radiation thermometer 20, and the measurement results are transmitted to the control unit 3. The control unit 3 monitors, based on the measurement results of the lower radiation thermometer 20, whether the temperature of the semiconductor wafer W has decreased to a predetermined temperature. After the temperature of the semiconductor wafer W has decreased to or below the predetermined temperature, the pair of transfer arms 11 of the transfer mechanism 10 again move horizontally from the retracted position to the transfer operation position and rise, causing the lift pins 12 to protrude from the upper surface of the susceptor 74 and receive the heat-treated semiconductor wafer W from the susceptor 74. Next, the transfer opening 66, which had been closed by the gate valve 162, is opened, and the semiconductor wafer W placed on the lift pins 12 is removed from the chamber 161 by a transfer robot external to the apparatus, completing the heat treatment of the semiconductor wafer W.

[0106] <Regarding the calculation unit 32> 8 is a functional block diagram showing the electrical configuration of a heat treatment apparatus 160 equipped with a calculation unit 32. The heat treatment apparatus 160 includes a control unit 3, an input unit 15, and a display unit 16. The input unit 15 includes input devices such as a keyboard, a pointing device, and a touch panel. The input unit 15 also includes a communication module for communicating with a host computer. The display unit 16 includes, for example, a liquid crystal display, and displays various information under the control of the control unit 3.

[0107] The control unit 3 includes a calculation processing unit such as a CPU. The control unit 3 controls, for example, the flash heating unit 5 and the halogen heating unit 4. The control unit 3 also includes a memory unit 31 and a calculation unit 32. The memory unit 31 includes a storage device such as a solid-state memory device and a hard disk drive. The memory unit 31 stores data and processing programs. In this embodiment, the memory unit 31 stores data measured by sensors (such as the sensors S1 to S11 described below) that measure parameters related to the heating of the semiconductor wafer W. The data includes recipe data. The recipe data is data for a plurality of recipes that define the processing content and processing procedures for the semiconductor wafer W.

[0108] The calculation unit 32 includes a relationship information analysis unit 32a, a learning model creation unit 32b, and a prediction unit 32c, which will be described in detail later. The relationship information analysis unit 32a, the learning model creation unit 32b, and the prediction unit 32c are function processing units realized by the CPU of the control unit 3 executing a predetermined processing program. The processing details of the relationship information analysis unit 32a, the learning model creation unit 32b, and the prediction unit 32c will be described further below.

[0109] As described above, the control unit 3 executes a predetermined processing program, thereby causing the processing in the heat treatment device 160 to proceed. For example, the control unit 3 controls the halogen heating unit 4 and the flash heating unit 5 to heat the semiconductor wafer W to a set temperature.

[0110] Returning to FIG. 1 , the upper radiation thermometer 25 includes an infrared sensor 29 that measures the temperature of the upper surface (front surface) of the semiconductor wafer W. The infrared sensor 29 generates a detection signal in response to receiving light and sends it to the control unit 3, which then calculates the temperature of the upper surface of the semiconductor wafer W. Similarly, the lower radiation thermometer 20 includes an infrared sensor 24 that measures the temperature of the lower surface (back surface) of the semiconductor wafer W. The infrared sensor 24 generates a detection signal in response to receiving light and sends it to the control unit 3, which then calculates the temperature of the lower surface of the semiconductor wafer W. The upper radiation thermometer 25 and the lower radiation thermometer 20 calculate the temperature of the semiconductor wafer W from the detection signal generated in response to receiving light, depending on the emissivity of the object to be measured. Therefore, the emissivity must be adjusted in advance depending on the object to be measured. The adjustment of the emissivity will be described in detail later.

[0111] The control unit 3 of the heat treatment apparatus 160 acquires the temperature of the semiconductor wafer W as well as a plurality of data correlated with the temperature of the semiconductor wafer W, and stores the acquired data in the memory unit 31. Examples of this data include the temperature of the quartz parts in the chamber 161 (for example, the temperature of the susceptor 74, the temperature of the upper chamber window 63, and the temperature of the lower chamber window 64), the temperature of the side surface of the chamber 161, the amount of power supplied to the halogen heating unit 4 (or each halogen lamp HL), the amount of light irradiated from the halogen heating unit 4 (or each halogen lamp HL), the amount of processing gas supplied into the chamber 161, and the amount of light irradiated from the flash heating unit 5 (or each flash lamp FL).

[0112] These data are acquired by sensors S1 to S11 serving as processing information acquisition unit 90. For example, temperature data on the bottom surface of semiconductor wafer W is acquired by lower radiation thermometer 20 (FIG. 1) (sensor S1 in FIG. 8), temperature data on the top surface of semiconductor wafer W is acquired by upper radiation thermometer 25 (FIG. 1) (sensor S2 in FIG. 8), temperature data on susceptor 74 is acquired by temperature sensor 91 (FIG. 1) (sensor S3 in FIG. 8), temperature data on upper chamber window 63 is acquired by temperature sensor 92 (FIG. 1) (sensor S4 in FIG. 8), temperature data on lower chamber window 64 is acquired by temperature sensor 93 (FIG. 1) (sensor S5 in FIG. 8), temperature data on the atmosphere in chamber 161 is acquired by temperature sensor 94 (FIG. 1) (sensor S6 in FIG. 8), and temperature data on the side surface of chamber 161 is acquired by temperature sensor 95 (FIG. 1) (sensor S7 in FIG. 8). The amount of power supplied to the halogen heating unit 4 (or each halogen lamp HL) is obtained from an ammeter 49a (FIG. 1) (sensor S8 in FIG. 8) connected to the power supply unit 49, the amount of light emitted from the halogen heating unit 4 (or each halogen lamp HL) is obtained from a light intensity sensor 97 (FIG. 1) (sensor S9 in FIG. 8), the amount of process gas supplied to the interior of the chamber 161 is obtained from a flow meter 98 (FIG. 1) (sensor S10 in FIG. 8) connected to the gas supply pipe 83, and the amount of light emitted from the flash heating unit 5 (or each flash lamp FL) is obtained from a light intensity sensor 96 (FIG. 1) (sensor S11 in FIG. 8). These data can be used to create a learning model. Of the data obtained by the sensors S1 to S11 serving as the processing information acquisition unit 90, for example, data that has a correlation with the temperature data of the semiconductor wafer W is selected for creating the learning model. As the sensor for acquiring this data, it is preferable to select, for example, the lower radiation thermometer 20, the upper radiation thermometer 25, the temperature sensor 95 for measuring the temperature of the side surface of the chamber 161, the temperature sensor 93 for measuring the temperature of the lower chamber window 64, the temperature sensor 92 for measuring the temperature of the upper chamber window 63, or the temperature sensor 91 for measuring the temperature of the susceptor 74. This is because the data measured by these sensors is considered to have a high correlation with the temperature data of the semiconductor wafer W.

[0113] The determination of whether the data has a correlation with the temperature of the semiconductor wafer W is made by the relationship information analysis unit 32a, which analyzes the relationship with the temperature data of the semiconductor wafer W. The relationship information analysis unit 32a determines whether there is a correlation, and the magnitude of the correlation, between the information acquired from each sensor and the temperature data of the semiconductor wafer W. Information determined by the relationship information analysis unit 32a to have a high correlation with the temperature of the semiconductor wafer W is adopted as data necessary for creating a learning model by the learning model creation unit 32b. On the other hand, data determined to have no or a low correlation with the temperature of the semiconductor wafer W may be excluded from the data used to create a learning model by the learning model creation unit 32b.

[0114] <Learning model creation flow by the calculation unit 32> The flow of creating a learning model for the heat treatment device 160 will be described below.

[0115] FIG. 9 is a flowchart showing the processing procedure for creating a learning model.

[0116] 9, in order for the calculation unit 32 to create a learning model, first, the temperature of a semiconductor wafer TC to which a thermocouple is attached (hereinafter referred to as a thermocouple-attached semiconductor wafer TC) that serves as training data is measured by the thermocouple (step ST1). The temperature measurement is performed on multiple thermocouple-attached semiconductor wafers TC. Next, simultaneously with the temperature measurement of the thermocouple-attached semiconductor wafers TC, each piece of data that serves as training data is acquired by each of the sensors S1 to S11 (processing information acquisition unit 90) installed in the heat treatment device 160 (step ST2).

[0117] The temperature data and each data acquired in steps ST1 and ST2 as training data are stored in the memory unit 31 (step ST3). Next, the learning model creation unit 32b creates a learning model (step ST4). The learning model is created by associating the temperature data with each data based on the correlation between the temperature data and each data. For example, a learning model formula for the temperature data of the thermocouple-equipped semiconductor wafer TC and the brightness data of the lower radiation thermometer 20 (or upper radiation thermometer 25) is derived from the relationship between the temperature data from the thermocouple and the brightness data from the lower radiation thermometer 20 (or upper radiation thermometer 25). Using this learning model formula, the temperature of the semiconductor wafer W is derived from the brightness data from the lower radiation thermometer 20 (or upper radiation thermometer 25).

[0118] Similarly, a learning model equation between the temperature data of the thermocouple-equipped semiconductor wafer TC and each piece of data is derived from the relationship between the temperature data of the thermocouple-equipped semiconductor wafer TC and each piece of data from other sensors. Furthermore, a learning model equation between each piece of data may be derived from these relationships.

[0119] In the learning model, weighting is optimized according to the magnitude of the correlation between the data to be predicted and the actual measured values ​​obtained by each sensor. The weighting increases as the correlation between the data to be predicted and the actual measured values ​​obtained by each sensor increases, and decreases as the correlation decreases.

[0120] FIG. 10 is a diagram showing the relationship between the predicted output value of the first sensor, the actual measured value of the second sensor, and the fitness value.

[0121] In this embodiment, the accuracy between the predicted output value and the actual measured value of the first sensor is calculated as a fitness value. This fitness value is obtained by optimizing the weighting described above. In other words, the fitness value indicates the magnitude of the correlation between the first sensor and the second sensor. In this way, based on the relationship between the actual measured values ​​of the two sensors, the predicted output value of one sensor can be derived from the actual measured value of the other sensor. In other words, the output value of one sensor can be predicted using a learning model formula created in advance.

[0122] 10, when sensor S1 is used as the first sensor and sensor S3 is used as the second sensor, the fitness value between them is, for example, 0.983. Similarly, when sensor S1 is used as the first sensor and sensor S4 is used as the second sensor, the fitness value between them is, for example, 0.963. When sensor S1 is used as the first sensor and sensor S5 is used as the second sensor, the fitness value between them is, for example, 0.913. When sensor S2 is used as the first sensor and sensor S6 is used as the second sensor, the fitness value between them is, for example, 0.955. When sensor S2 is used as the first sensor and sensor S7 is used as the second sensor, the fitness value between them is, for example, 0.875.

[0123] Then, the predicted output value S1A of the first sensor S1 is calculated using a model formula S1A=a(t). Note that the model formula a(t) is calculated, for example, using the following formula 1.

[0124]

number

[0125] Similarly, the predicted output value S1A of the first sensor S1 is calculated, for example, by a model formula S1A=b(t), the predicted output value S1A of the first sensor S1 is calculated, for example, by a model formula S1A=c(t), the predicted output value S2A of the first sensor S2 is calculated, for example, by a model formula S2A=d(t), and the predicted output value S2A of the first sensor S2 is calculated, for example, by a model formula S2A=e(t). Note that b(t), c(t), d(t), and e(t) are formulas created as learning models in the learning model creation unit 32b.

[0126] As shown in the above formula (1), in this embodiment, the learning model creation unit 32b creates a learning model including time-series elements. Specifically, the learning model predicts the output value of the first sensor S1 based on one or more pieces of time-series data measured by the first sensor S1 and one or more pieces of time-series data measured by the second sensor S3. As shown in formula (1), the output value of the first sensor S1 at time t (any time point) predicted by the learning model is calculated using, for example, the actual measurement value of the first sensor S1 at time t-1 in the past, the actual measurement value of the first sensor S1 at time t-2 in the past, and the actual measurement value of the second sensor S3 at time t-1 in the past. By using the actual measurement values ​​at past times in this way, the accuracy of the predicted output value of the first sensor S1 is improved. This improved accuracy in predicting the output value of the first sensor allows for highly accurate measurement of the temperature of the semiconductor wafer W in the chamber 161 before the stable temperature is reached.

[0127] When creating a learning model equation such as Equation 1, it is necessary to determine how much past data should be included in the prediction for each of the actual measurement values ​​from the first sensor S1 and the second sensor S3. This determination can be appropriately set as a hyperparameter. For example, for a component with good thermal conductivity, the predicted output value may be calculated using a learning model equation that uses only the most recent data (e.g., data from time t-1 in the past). On the other hand, for a component with poor thermal conductivity, the predicted output value is preferably calculated using a learning model equation that also includes data from several steps back (e.g., time t-1, time t-2, time t-3, ...). In this way, the hyperparameters are set taking into account the properties of the component being measured by each sensor, the fitness values ​​of correlated sensor output values, and the like.

[0128] By improving the accuracy of the predicted output value of the first sensor S1 calculated in this manner, the learning model can be used for highly accurate feedback control and recipe prediction in the manufacturing process of semiconductor wafers W using this output value.

[0129] <Semiconductor wafer W processing flow using learning model> FIG. 11 is a flowchart showing the processing procedure for a semiconductor wafer W using a learning model.

[0130] As shown in FIG. 11, in order to accurately measure the temperature of the semiconductor wafer W using the learning model, first, each data is acquired by each of the sensors S1 to S11 including the lower pyrometer 20 (step ST11).

[0131] Next, the temperature of the semiconductor wafer W at time t is predicted (step ST12). By utilizing the learning model formula, the temperature of the semiconductor wafer W at time t is predicted by the prediction unit 32c from each piece of data. At this time, as described above, the learning model formula also includes the relationship with the past actual measurement values ​​of the necessary sensors, so that the temperature of the semiconductor wafer W is predicted with high accuracy. The temperature of the semiconductor wafer W is predicted as appropriate until the heat treatment of the semiconductor wafer W is completed.

[0132] In this state, the semiconductor wafer W is heat-treated in the chamber 161 (step ST13). During the heat treatment, feedback control is performed using the temperature predicted in step ST12 (step ST14). This feedback control, for example, compares the predicted output value for the temperature of the semiconductor wafer W with a target value set in the recipe, and if there is a difference between the predicted output value and the target value (or if the difference exceeds a preset threshold), various components of the heat treatment apparatus 160 are controlled so that the predicted output value matches the target value. Examples of the various components controlled include the output values ​​of the halogen lamps HL and flash lamps FL, the heating time of the halogen lamps HL, and the amount of supply gas. This allows the predicted output value to approach the target value.

[0133] In this manner, the heat treatment of the semiconductor wafer W in this embodiment is completed.

[0134] <Effects of the above-described embodiments> Next, examples of effects obtained by the above-described embodiments will be described. Note that in the following description, the effects will be described based on the specific configurations exemplified in the above-described embodiments, but these may be replaced with other specific configurations exemplified in the present specification as long as the same effects are obtained.

[0135] Furthermore, the replacement may be made across multiple embodiments, i.e., configurations illustrated in different embodiments may be combined to produce the same effect.

[0136] The heat treatment apparatus 160 of the embodiment described above includes a chamber 161 that accommodates a semiconductor wafer W, a halogen heating unit 4 and a flash heating unit 5 that heat the semiconductor wafer W, a plurality of sensors S1 to S11 that measure parameters related to the heating of the semiconductor wafer W, a memory unit 31 that stores data measured by the plurality of sensors S1 to S11, and a calculation unit 32 that predicts the output value of the first sensor based on data measured by a first sensor of the plurality of sensors S1 to S11 and data measured by a second sensor that has a correlation with the first sensor.

[0137] With this configuration, the temperature of the semiconductor wafer W can be controlled with high precision even before the temperature inside the chamber 161 has reached a stable temperature. In other words, since the temperature of the semiconductor wafer W can be predicted with high precision, there is no need to use a dummy wafer to wait for the temperature inside the chamber 161 to reach a stable temperature. This eliminates the cost and time required for processing the dummy wafer, and suppresses a decrease in productivity. In addition, the temperature of the semiconductor wafer W inside the chamber 161 before the stable temperature has been reached can also be measured with high precision.

[0138] In addition, the calculation unit 32 predicts the output value of the first sensor based on one or more pieces of time-series data measured by the first sensor and one or more pieces of time-series data measured by the second sensor.

[0139] With this configuration, even if data is measured for a component with which the correlation is thought to be relatively small, the output value of a sensor measuring another component can be predicted with high accuracy from that data.

[0140] Furthermore, the calculation unit 32 calculates the accuracy between the predicted output value of the first sensor and the actually measured data as a fitness value indicating the magnitude of the correlation between the first sensor and the second sensor.

[0141] With this configuration, even if there is little correlation between the output value of the first sensor and the output value of the second sensor, the output value of the first sensor can be predicted with high accuracy by adjusting the fitness value.

[0142] The plurality of sensors S1 to S11 also includes a temperature sensor (lower radiation thermometer 20 or upper radiation thermometer 25) that measures the temperature of the semiconductor wafer W.

[0143] According to this configuration, the temperature of the semiconductor wafer W during heat treatment, which is important for improving the quality of the semiconductor wafer W, can be controlled with high precision.

[0144] The plurality of sensors S1 to S11 also includes a temperature sensor 95 that measures the temperature of the side surface of the chamber 161.

[0145] With this configuration, the output value of the temperature sensor (lower radiation thermometer 20 or upper radiation thermometer 25) of the semiconductor wafer W can be predicted with high accuracy by utilizing temperature data of the side of the chamber 161, which is thought to have a high correlation with the temperature of the semiconductor wafer W.

[0146] The chamber 161 further includes a halogen heating unit 4 that irradiates light onto the semiconductor wafer W housed within the chamber 161 to preheat the semiconductor wafer W, and a flash heating unit 5 that irradiates light onto the semiconductor wafer W to bring the semiconductor wafer W to a processing temperature. The chamber 161 is provided with an upper chamber window 63 and a lower chamber window 64 as light-transmitting windows that transmit the light irradiated from the halogen heating unit 4 and the flash heating unit 5. The plurality of sensors S1 to S11 further includes a temperature sensor S92 or a temperature sensor S93 that measures the temperature of the upper chamber window 63 or the lower chamber window 64.

[0147] With this configuration, the output value of the temperature sensor (lower radiation thermometer 20 or upper radiation thermometer 25) of the semiconductor wafer W can be predicted with high accuracy by utilizing the temperature data of the upper chamber window 63 or the lower chamber window 64, which is thought to have a high correlation with the temperature of the semiconductor wafer W.

[0148] The apparatus further includes a susceptor 74 on which a semiconductor wafer W is placed and which transmits light irradiated onto the semiconductor wafer W from the halogen heating unit 4 or the flash heating unit 5. The plurality of sensors S1 to S11 includes a temperature sensor 91 that measures the temperature of the susceptor 74.

[0149] With this configuration, the output value of the temperature sensor (lower radiation thermometer 20 or upper radiation thermometer 25) of the semiconductor wafer W can be predicted with high accuracy by utilizing the temperature data of the susceptor 74, which is thought to have a high correlation with the temperature of the semiconductor wafer W.

[0150] <Modifications of the above-described embodiments> In the embodiments described above, the material, composition, dimensions, shape, relative positional relationship, or implementation conditions of each component may also be described, but these are merely examples in all aspects and are not limited to those described in this specification.

[0151] Therefore, countless modifications and equivalents not shown as examples are contemplated within the scope of the technology disclosed in the present specification, including, for example, modifying, adding, or omitting at least one component, and further, extracting at least one component in at least one embodiment and combining it with a component in another embodiment.

[0152] In the above-described embodiment, the calculation unit 32 is configured to include the relationship information analysis unit 32a and the learning model creation unit 32b, but this is not limiting. The calculation unit 32 may not include the relationship information analysis unit 32a, and instead, a correlation between the temperature of the semiconductor wafer W that has been analyzed (or set) in advance may be stored in the memory unit 31. Furthermore, the calculation unit 32 (232) may not include the learning model creation unit 32b, and instead, a learning model that has been created in advance may be stored in the memory unit 31. Then, the calculation unit 32 may be configured to calculate a predicted output value for the temperature of the semiconductor wafer W based on this stored learning model.

[0153] Furthermore, in the above-described embodiment, the calculation unit 32 includes the prediction unit 32c, but this is not limiting. The calculation unit 32 may not include the prediction unit 32c, and the function of the prediction unit 32c may be provided in a cloud that can remotely access the heat treatment device 160 (260). In this case, data obtained by the processing information acquisition unit 90 (each sensor) and measurements by the lower radiation thermometer 20 (or / and upper radiation thermometer 25) may be transmitted to the cloud, and the results predicted by the cloud may be received by the control unit 3. In this case, the data obtained by the processing information acquisition unit 90 (each sensor) and measurements by the lower radiation thermometer 20 (or / and upper radiation thermometer 25) may be stored in the cloud. The entire function of the control unit 3 may also be provided in the cloud. Furthermore, the function of the prediction unit 32c may be provided in a cloud that can access (transmit and receive) data from the control unit 3 via wired or wireless connection, not limited to the cloud.

[0154] In the above-described embodiment, a configuration is adopted in which the output value of a first sensor among the multiple sensors S1 to S11 is predicted based on data measured by the first sensor and data measured by the second sensor, but this is not limited to this.

[0155] The output value of the first sensor may be predicted based on data measured by a first sensor, a second sensor, and a third sensor, or may be predicted based on data measured by multiple sensors, such as a fourth sensor, a fifth sensor, and so on.

[0156] Furthermore, in the embodiments described above, when a material name is mentioned without any particular specification, it is assumed that the material may contain other additives, such as an alloy, unless a contradiction arises. [Explanation of symbols]

[0157] 3. Control Unit 4 Halogen heating section 5 Flash heating section 7 Holding part 10 Transfer mechanism 11 Transfer arm 12 lift pins 13 Horizontal movement mechanism 14 Lifting mechanism 15 Input section 16 Display 20 Lower radiation thermometer 21,26 Transparent window 24,29 Infrared sensor 25 Upper radiation thermometer 31 Storage section 32 Arithmetic section 32a Relationship Information Analysis Department 32b Learning model creation section 32c Prediction Department 41 Case 43,52 Reflector 49 Power supply section 49a ammeter 51 Case 53 Lamp light emission window 61 Chamber side 61a,61b through hole 62 recess 63 Upper chamber window 64 Lower chamber window 65 Heat Treatment Space 66 Transport opening 68,69 Reflective ring 71 Base Ring 72 Connecting part 74 Susceptor 75 Retaining Plate 75a Holding surface 76 Guide Ring 77 Support pin 78 Opening 79 Through Hole 81 Gas supply hole 82,87 Buffer space 83 Gas supply pipe 84 Valve 85 Process gas supply source 86 Gas exhaust vent 88 Gas Exhaust Pipe 89,192 valves 90 Processing information acquisition unit 91,92,93,94,95 Temperature sensors 96,97 Light sensor 98 Flow meter 160 Heat Treatment Equipment 161 Chamber 162 Gate Valve 190 Exhaust mechanism 191 Gas exhaust pipe TC Semiconductor wafer with thermocouple W Semiconductor wafer

Claims

1. a chamber for housing the substrate; a heating unit that heats the substrate; a plurality of sensors for measuring parameters related to the heating of the substrate; a control unit that controls the heating unit; Equipped with The control unit a storage unit for storing data measured by the plurality of sensors; a calculation unit that performs calculation processing on the data stored in the storage unit; Equipped with the calculation unit includes a prediction unit that predicts the temperature of the substrate from an output value of any of the plurality of sensors based on a learning model created in advance; The prediction unit predicts the temperature of the substrate based on an output value of a first sensor derived from time series data measured by a first sensor among the plurality of sensors and time series data measured by a second sensor having a correlation with the first sensor.

2. 2. The heat treatment apparatus according to claim 1, the calculation unit derives an output value of the first sensor at a predetermined time point based on an actual measurement value of the first sensor at a first past time point, an actual measurement value of the first sensor at a second past time point, and an actual measurement value of the second sensor at the first past time point; The prediction unit predicts the temperature of the substrate at the predetermined time point.

3. In the heat treatment device according to claim 2, The calculation unit multiplies each of the actual measured value of the first sensor at the first past time, the actual measured value of the first sensor at the second past time, and the actual measured value of the second sensor at the first past time by a fitness value that is optimized with weighting according to the correlation between the first sensor and the second sensor, to derive the output value of the first sensor at the specified time.

4. In the heat treatment device according to any one of claims 1 to 3, The control unit performs feedback control of the heating unit so that the predicted temperature of the substrate matches the target value set in a recipe when a difference between the predicted temperature of the substrate and the target value set in a recipe exceeds a predetermined threshold.

5. In the heat treatment device according to claim 1, The calculation unit creates the learning model using the temperature of the substrate measured by a thermocouple as training data.

6. In the heat treatment device according to claim 1, The plurality of sensors include one or more selected from the group consisting of a lower radiation thermometer that measures the temperature of the underside of the substrate, an upper radiation thermometer that measures the temperature of the upper surface of the substrate, a temperature sensor that measures the temperature of a susceptor that holds the substrate, a temperature sensor that measures the temperature of an upper chamber window of the chamber, a temperature sensor that measures the temperature of a lower chamber window of the chamber, a temperature sensor that measures the temperature of an atmosphere inside the chamber, a temperature sensor that measures the temperature of a side surface of the chamber, an ammeter that measures the amount of power supplied to the heating unit, a light intensity sensor that measures the amount of light irradiated from the heating unit, and a flowmeter that measures the flow rate of a process gas supplied into the chamber.

7. 7. The heat treatment apparatus according to claim 6, The second sensor is one selected from the group consisting of a temperature sensor that measures the temperature of the susceptor, a temperature sensor that measures the temperature of the upper chamber window, a temperature sensor that measures the temperature of the lower chamber window, a temperature sensor that measures the temperature of the atmosphere inside the chamber, and a temperature sensor that measures the temperature of the side surface of the chamber.

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