JP2021077660A - Manufacturing method of susceptor, susceptor and heat treatment apparatus - Google Patents

Abstract

To provide a technique capable of improving uniformity of in-plane temperature distribution of a substrate.SOLUTION: In-plane temperature distribution is calculated, which is generated in the semiconductor wafer when light irradiation is performed from the lower side by a halogen lamp in the state where a semiconductor wafer is supported in a susceptor 74. A partial region of a surface of the susceptor 74 opposed to a high-temperature region of the semiconductor wafer at a predetermined temperature or higher in the in-plane temperature distribution is made into a rough surface. The step of acquiring the temperature distribution of the semiconductor wafer supported by such a susceptor 74 and the step of applying surface roughening processing to the partial region of the susceptor 74 on the basis of the temperature distribution are repeated a plurality of times, thereby forming a plurality of rough surface regions in the susceptor 74. The light irradiation is performed from the halogen lamp while supporting the semiconductor wafer in the susceptor 74, thereby improving uniformity of the in-plane temperature distribution of the semiconductor wafer.SELECTED DRAWING: Figure 19

Description

The present invention relates to a susceptor that supports a thin plate-shaped precision electronic substrate (hereinafter, simply referred to as “substrate”) such as a semiconductor wafer that is heated by light irradiation, a method for manufacturing the susceptor, and a heat treatment apparatus equipped with the susceptor.

In the semiconductor device manufacturing process, flash lamp annealing (FLA), which heats a semiconductor wafer in an extremely short time, has attracted attention. Flash lamp annealing uses a xenon flash lamp (hereinafter, simply referred to as "flash lamp" to mean a xenon flash lamp) to irradiate the surface of the semiconductor wafer with flash light, so that only the surface of the semiconductor wafer is extremely exposed. This is a heat treatment technique that raises the temperature in a short time (several milliseconds or less).

The radiation spectral distribution of the xenon flash lamp is from the ultraviolet region to the near infrared region, and the wavelength is shorter than that of the conventional halogen lamp, which is almost the same as the basic absorption band of the silicon semiconductor wafer. Therefore, when the semiconductor wafer is irradiated with the flash light from the xenon flash lamp, the transmitted light is small and the temperature of the semiconductor wafer can be rapidly raised. It has also been found that if the flash light is irradiated for an extremely short time of several milliseconds or less, the temperature can be selectively raised only in the vicinity of the surface of the semiconductor wafer.

Such flash lamp annealing is utilized for processes that require heating for a very short time, for example, activation of impurities injected into a semiconductor wafer. By irradiating the surface of a semiconductor wafer into which impurities have been implanted by the ion implantation method with flash light from a flash lamp, the surface of the semiconductor wafer can be raised to the activation temperature for a very short time, and the impurities are deeply diffused. Only impurity activation can be performed without causing it.

As a heat treatment apparatus using such a xenon flash lamp, in Patent Documents 1 and 2, a pulse emitting lamp such as a flash lamp is arranged on the front surface side of the semiconductor wafer, and a continuous lighting lamp such as a halogen lamp is arranged on the back surface side. However, there is disclosed a combination thereof that performs a desired heat treatment. In the heat treatment apparatus disclosed in Patent Documents 1 and 2, the semiconductor wafer is preheated to a certain temperature by a halogen lamp or the like, and then the temperature is raised to a desired processing temperature by pulse heating from a flash lamp or the like.

When preheating is performed with a halogen lamp as disclosed in Patent Documents 1 and 2, there is a process merit that the semiconductor wafer can be heated to a relatively high preheating temperature in a short time. However, the problem that the temperature of the peripheral portion of the wafer becomes lower than that of the central portion tends to occur. Possible causes of such non-uniform temperature distribution include heat radiation from the peripheral edge of the semiconductor wafer, heat conduction from the peripheral edge of the semiconductor wafer to a relatively low temperature quartz susceptor, and the like. Therefore, in order to solve such a problem, in Patent Document 3, a cylindrical louver formed of a translucent material is installed between the halogen lamp and the semiconductor wafer, and is in-plane during preheating. It has been proposed to make the temperature distribution uniform.

Japanese Unexamined Patent Publication No. 60-258928 Japanese Patent Application Laid-Open No. 2005-527772 Japanese Unexamined Patent Publication No. 2012-174879

However, even if the technique proposed in Patent Document 3 is used, it is difficult to make the in-plane temperature distribution of the semiconductor wafer sufficiently uniform when light irradiation is performed from a halogen lamp.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a technique capable of improving the uniformity of the in-plane temperature distribution of a substrate.

In order to solve the above problems, the invention of claim 1 is a method of manufacturing a susceptor that supports a substrate heated by light irradiation, when the substrate supported by the susceptor is irradiated with light from below the susceptor. A temperature distribution acquisition step for acquiring the temperature distribution generated on the substrate, and a roughening processing step for roughening a part of the surface of the susceptor facing the high temperature region of the substrate which is equal to or higher than a predetermined temperature in the temperature distribution. It is characterized by having.

Further, the invention of claim 2 is characterized in that, in the method for manufacturing a susceptor according to the invention of claim 1, the temperature distribution acquisition step and the roughening processing step are repeated a plurality of times.

Further, the invention of claim 3 is the method of manufacturing a susceptor according to the invention of claim 1 or 2, wherein the higher the temperature in the high temperature region of the substrate, the higher the temperature of the susceptor facing the position. It is characterized in that the surface roughness of the portion is roughened.

Further, the invention of claim 4 is characterized in that, in the method for manufacturing a susceptor according to any one of claims 1 to 3, the lower surface of the susceptor is a rough surface.

The invention of claim 5 is a susceptor that supports a substrate that is heated by light irradiation, and is predetermined in terms of the temperature distribution that occurs on the substrate when the substrate supported by the susceptor is irradiated with light from below the susceptor. A rough surface is formed in a part of the surface of the susceptor facing the high temperature region of the substrate above the temperature.

Further, in the invention of claim 6, in the susceptor according to the invention of claim 5, the higher the temperature in the high temperature region of the substrate, the rougher the surface roughness of the portion of the susceptor facing the position where the temperature rises. It is characterized by becoming.

Further, the invention of claim 7 is characterized in that, in the susceptor according to the invention of claim 5 or 6, a rough surface is formed on the lower surface of the susceptor.

The invention according to claim 8 is a heat treatment apparatus for heating the substrate by irradiating the substrate with light according to claim 5, wherein the chamber for accommodating the substrate and the chamber provided in the chamber to support the substrate. It is characterized by comprising the susceptor according to any one of claims 7 and a continuous lighting lamp that heats the substrate by irradiating light from below the susceptor.

According to the inventions of claims 1 to 4, the temperature distribution generated on the substrate when the substrate supported by the susceptor is irradiated with light from below the susceptor is acquired, and the temperature distribution of the substrate is equal to or higher than a predetermined temperature. Since a part of the surface of the susceptor facing the high temperature region is made a rough surface, the illuminance in the high temperature region of the substrate is reduced, and the uniformity of the in-plane temperature distribution of the substrate can be improved.

In particular, according to the invention of claim 3, the higher the temperature in the high temperature region of the substrate, the rougher the surface roughness of the portion of the susceptor facing the position where the temperature rises, so that the surface of the substrate becomes more accurate. The uniformity of the internal temperature distribution can be improved.

According to the inventions of claims 5 to 8, the susceptor facing the high temperature region of the substrate whose temperature distribution generated on the substrate when the substrate supported by the susceptor is irradiated with light from below the susceptor is equal to or higher than a predetermined temperature. Since a rough surface is formed in a part of the surface, the illuminance in the high temperature region of the substrate is reduced, and the uniformity of the in-plane temperature distribution of the substrate can be improved.

In particular, according to the invention of claim 6, the higher the temperature in the high temperature region of the substrate, the rougher the surface roughness of the portion of the susceptor facing the position where the temperature rises, so that the surface of the substrate becomes more accurate. The uniformity of the internal temperature distribution can be improved.

It is a vertical cross-sectional view which shows the structure of the heat treatment apparatus which concerns on this invention. It is a perspective view which shows the whole appearance of the holding part. It is a top view of the susceptor. It is sectional drawing of the susceptor. It is a top view of the transfer mechanism. It is a side view of the transfer mechanism. It is a top view which shows the arrangement of a plurality of halogen lamps. It is a figure which shows an example of the in-plane temperature distribution generated in the semiconductor wafer. It is a figure which shows the effect of the roughening process in FIG. It is a top view of the susceptor which roughened a part area. It is a figure which shows an example of the in-plane temperature distribution which occurs in the semiconductor wafer supported by the susceptor shown in FIG. It is a figure which shows the effect of the new roughening process in FIG. It is a top view of the susceptor which roughened a part area. It is a figure which shows an example of the in-plane temperature distribution which occurs in the semiconductor wafer supported by the susceptor shown in FIG. It is a figure which shows the effect of the new roughening process in FIG. It is a top view of the susceptor which roughened a part area. It is a figure which shows an example of the in-plane temperature distribution which occurs in the semiconductor wafer supported by the susceptor shown in FIG. It is a figure which shows the effect of the new roughening process in FIG. It is a top view of the susceptor which roughened a part area. It is a figure which shows an example of the in-plane temperature distribution which occurs in the semiconductor wafer supported by the susceptor shown in FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a vertical cross-sectional view showing the configuration of the heat treatment apparatus 1 according to the present invention. The heat treatment apparatus 1 of FIG. 1 is a flash lamp annealing apparatus that heats a disk-shaped semiconductor wafer W as a substrate by irradiating the semiconductor wafer W with flash light. The size of the semiconductor wafer W to be processed is not particularly limited, but is, for example, φ300 mm or φ450 mm. In addition, in FIG. 1 and each subsequent drawing, the dimensions and numbers of each part are exaggerated or simplified as necessary for easy understanding.

The heat treatment apparatus 1 includes a chamber 6 for accommodating a semiconductor wafer W, a flash heating unit 5 containing a plurality of flash lamps FL, and a halogen heating unit 4 containing a plurality of halogen lamps HL. A flash heating unit 5 is provided on the upper side of the chamber 6, and a halogen heating unit 4 is provided on the lower side. Further, the heat treatment apparatus 1 includes a holding portion 7 that holds the semiconductor wafer W in a horizontal posture inside the chamber 6, a transfer mechanism 10 that transfers the semiconductor wafer W between the holding portion 7 and the outside of the apparatus. To be equipped. Further, the heat treatment apparatus 1 includes a halogen heating unit 4, a flash heating unit 5, and a control unit 3 that controls each operation mechanism provided in the chamber 6 to execute heat treatment of the semiconductor wafer W.

The chamber 6 is configured by mounting quartz chamber windows above and below the tubular chamber side portion 61. The chamber side portion 61 has a substantially tubular shape with upper and lower openings, and the upper chamber window 63 is attached to the upper opening and closed, and the lower chamber window 64 is attached to the lower opening and closed. ing. The upper chamber window 63 constituting the ceiling portion of the chamber 6 is a disk-shaped member formed of quartz, and functions as a quartz window that transmits the flash light emitted from the flash heating portion 5 into the chamber 6. Further, the lower chamber window 64 constituting the floor portion of the chamber 6 is also a disk-shaped member formed of quartz, and functions as a quartz window that transmits light from the halogen heating portion 4 into the chamber 6.

A reflective ring 68 is attached to the upper part of the inner wall surface of the chamber side portion 61, and a reflective ring 69 is attached to the lower part. The reflective rings 68 and 69 are both formed in an annular shape. The upper reflective ring 68 is attached by fitting from the upper side of the chamber side portion 61. On the other hand, the lower reflective ring 69 is attached by fitting it from the lower side of the chamber side portion 61 and fastening it with a screw (not shown). That is, both the reflective rings 68 and 69 are detachably attached to the chamber side portion 61. The inner space of the chamber 6, that is, the space surrounded by the upper chamber window 63, the lower chamber window 64, the chamber side 61, and the reflection rings 68, 69 is defined as the heat treatment space 65.

By attaching the reflective rings 68 and 69 to the chamber side portion 61, a recess 62 is formed on the inner wall surface of the chamber 6. That is, a recess 62 is formed which is surrounded by the central portion of the inner wall surface of the chamber side 61 to which the reflection rings 68 and 69 are not mounted, the lower end surface of the reflection ring 68, and the upper end surface of the reflection ring 69. .. The recess 62 is formed in an annular shape along the horizontal direction on the inner wall surface of the chamber 6 and surrounds the holding portion 7 that holds the semiconductor wafer W. The chamber side 61 and the reflective rings 68 and 69 are made of a metal material (for example, stainless steel) having excellent strength and heat resistance.

Further, the chamber side portion 61 is provided with a transport opening (furnace port) 66 for loading and unloading the semiconductor wafer W into and out of the chamber 6. The transport opening 66 can be opened and closed by a gate valve 185. The transport opening 66 is communicated with the outer peripheral surface of the recess 62. Therefore, when the gate valve 185 opens the transport opening 66, the semiconductor wafer W is carried in from the transport opening 66 through the recess 62 into the heat treatment space 65 and the semiconductor wafer W is carried out from the heat treatment space 65. It can be performed. Further, when the gate valve 185 closes the transport opening 66, the heat treatment space 65 in the chamber 6 becomes a closed space.

Further, a through hole 61a is formed in the chamber side portion 61. A radiation thermometer 20 is attached to a portion of the outer wall surface of the chamber side 61 where the through hole 61a is provided. The through hole 61a is a cylindrical hole for guiding the infrared light emitted from the lower surface of the semiconductor wafer W held by the susceptor 74, which will be described later, to the radiation thermometer 20. The through hole 61a is provided so as to be inclined with respect to the horizontal direction so that the axis in the penetrating direction intersects the main surface of the semiconductor wafer W held by the susceptor 74. Therefore, the radiation thermometer 20 is provided diagonally below the susceptor 74. A transparent window 21 made of a barium fluoride material that transmits infrared light in a wavelength region that can be measured by the radiation thermometer 20 is attached to the end of the through hole 61a on the side facing the heat treatment space 65.

Further, a gas supply hole 81 for supplying the processing gas to the heat treatment space 65 is formed in the upper part of the inner wall of the chamber 6. The gas supply hole 81 is formed at a position above the recess 62, and may be provided in the reflection ring 68. The gas supply hole 81 is communicated with the gas supply pipe 83 via a buffer space 82 formed in an annular shape inside the side wall of the chamber 6. The gas supply pipe 83 is connected to the processing gas supply source 85. Further, a valve 84 is inserted in the middle of the path of the gas supply pipe 83. When the valve 84 is opened, the processing gas is supplied from the processing gas supply source 85 to the buffer space 82. The processing gas that has flowed into the buffer space 82 flows so as to expand in the buffer space 82 having a smaller fluid resistance than the gas supply hole 81, and is supplied from the gas supply hole 81 into the heat treatment space 65. As the treatment gas, for example _{, an inert gas such as nitrogen (N 2} ), a reactive gas such as hydrogen (H ₂ ) or ammonia (NH ₃ ), or a mixed gas in which they are mixed can be used (this). Nitrogen gas in the embodiment).

On the other hand, a gas exhaust hole 86 for exhausting the gas in the heat treatment space 65 is formed in the lower part of the inner wall of the chamber 6. The gas exhaust hole 86 is formed at a position below the recess 62, and may be provided in the reflection ring 69. The gas exhaust hole 86 is communicated with the gas exhaust pipe 88 via a buffer space 87 formed in an annular shape inside the side wall of the chamber 6. The gas exhaust pipe 88 is connected to the exhaust unit 190. Further, a valve 89 is inserted in the middle of the path of the gas exhaust pipe 88. When the valve 89 is opened, the gas in the heat treatment space 65 is discharged from the gas exhaust hole 86 to the gas exhaust pipe 88 via the buffer space 87. A plurality of gas supply holes 81 and gas exhaust holes 86 may be provided along the circumferential direction of the chamber 6, or may be slit-shaped. Further, the processing gas supply source 85 and the exhaust unit 190 may be a mechanism provided in the heat treatment apparatus 1, or may be a utility of a factory in which the heat treatment apparatus 1 is installed.

FIG. 2 is a perspective view showing the overall appearance of the holding portion 7. The holding portion 7 includes 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. That is, the entire holding portion 7 is made of quartz.

The base ring 71 is an arc-shaped quartz member in which a part is missing from the ring shape. This missing portion is provided to prevent interference between the transfer arm 11 of the transfer mechanism 10 described later and the base ring 71. By placing the base ring 71 on the bottom surface of the recess 62, the base ring 71 is supported on the wall surface of the chamber 6 (see FIG. 1). A plurality of connecting portions 72 (four in the present embodiment) are erected on the upper surface of the base ring 71 along the circumferential direction of the ring shape. The connecting portion 72 is also a quartz member, and is fixed to the base ring 71 by welding.

The susceptor 74 is supported by four connecting portions 72 provided on the base ring 71. FIG. 3 is a plan view of the susceptor 74. Further, FIG. 4 is a cross-sectional view of the susceptor 74. The susceptor 74 includes a holding plate 75, a guide ring 76 and a plurality of substrate support pins 77. The holding plate 75 is a substantially circular flat plate-shaped 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 plane size larger than that of the semiconductor wafer W.

A guide ring 76 is installed on the upper peripheral edge of the holding plate 75. The guide ring 76 is a ring-shaped member having an inner diameter larger than the diameter of the semiconductor wafer W. For example, when the diameter of the semiconductor wafer W is φ300 mm, the inner diameter of the guide ring 76 is φ320 mm. The inner circumference of the guide ring 76 is a tapered surface that widens upward from the holding plate 75. The guide ring 76 is made of quartz similar to the holding plate 75. 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 integral member.

A region of the upper surface of the holding plate 75 inside the guide ring 76 is a flat holding surface 75a for holding the semiconductor wafer W. A plurality of substrate support pins 77 are erected on the holding surface 75a of the holding plate 75. In the present embodiment, a total of 12 substrate support pins 77 are erected at every 30 ° along the circumference of the outer circumference circle (inner circumference circle of the guide ring 76) of the holding surface 75a and the concentric circles. The diameter of the circle in which the 12 substrate support pins 77 are arranged (distance between the opposing substrate 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, the diameter is φ270 mm to φ280 mm (this implementation). In the form, it is φ270 mm). Each substrate support pin 77 is made of quartz. The plurality of substrate support pins 77 may be provided on the upper surface of the holding plate 75 by welding, or may be processed integrally with the holding plate 75.

Returning to FIG. 2, the four connecting portions 72 erected on the base ring 71 and the peripheral edge portion of the holding plate 75 of the susceptor 74 are fixed by welding. That is, the susceptor 74 and the base ring 71 are fixedly connected by the connecting portion 72. The base ring 71 of the holding portion 7 is supported on the wall surface of the chamber 6, so that the holding portion 7 is mounted on the chamber 6. When the holding portion 7 is mounted on the chamber 6, the holding plate 75 of the susceptor 74 is in a horizontal posture (a posture 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.

The semiconductor wafer W carried into the chamber 6 is placed and held in a horizontal posture on the susceptor 74 of the holding portion 7 mounted on the chamber 6. At this time, the semiconductor wafer W is supported by the twelve substrate support pins 77 erected on the holding plate 75 and held by the susceptor 74. More precisely, the upper ends of the 12 substrate support pins 77 come into contact with the lower surface of the semiconductor wafer W to support the semiconductor wafer W. Since the heights of the 12 substrate support pins 77 (distance from the upper end of the substrate support pins 77 to the holding surface 75a of the holding plate 75) are uniform, the semiconductor wafer W is placed in a horizontal position by the 12 substrate support pins 77. Can be supported.

Further, the semiconductor wafer W is supported by a plurality of substrate support pins 77 from the holding surface 75a of the holding plate 75 at a predetermined interval. The thickness of the guide ring 76 is larger than the height of the substrate support pin 77. Therefore, the horizontal misalignment of the semiconductor wafer W supported by the plurality of substrate support pins 77 is prevented by the guide ring 76.

Further, as shown in FIGS. 2 and 3, the holding plate 75 of the susceptor 74 is formed with an opening 78 that penetrates vertically. The opening 78 is provided so that the radiation thermometer 20 receives the synchrotron radiation (infrared light) radiated from the lower surface of the semiconductor wafer W. That is, the radiation thermometer 20 receives the light radiated from the lower surface of the semiconductor wafer W through the transparent window 21 mounted in the opening 78 and the through hole 61a of the chamber side portion 61, and measures the temperature of the semiconductor wafer W. Measure. Further, the holding plate 75 of the susceptor 74 is provided with four through holes 79 through which the lift pin 12 of the transfer mechanism 10 described later penetrates for the transfer of the semiconductor wafer W. In the present embodiment, a part of the lower surface of the holding plate 75 of the susceptor 74 is roughened to reduce the transmittance, which will be described later.

FIG. 5 is a plan view of the transfer mechanism 10. Further, FIG. 6 is a side view of the transfer mechanism 10. The transfer mechanism 10 includes two transfer arms 11. The transfer arm 11 has an arc shape that generally follows the annular recess 62. Two lift pins 12 are erected on each transfer arm 11. The transfer arm 11 and the lift pin 12 are made of quartz. Each transfer arm 11 is rotatable by a horizontal movement mechanism 13. The horizontal movement mechanism 13 has a transfer operation position (solid line position in FIG. 5) for transferring the semiconductor wafer W to the holding portion 7 and the semiconductor wafer W held by the holding portion 7. It is horizontally moved to and from the retracted position (two-dot chain line position in FIG. 5) that does not overlap in a plan view. The horizontal movement mechanism 13 may be one in which each transfer arm 11 is rotated by an individual motor, or a pair of transfer arms 11 are interlocked and rotated by one motor using a link mechanism. It may be something to move.

Further, the pair of transfer arms 11 are moved up and down together with the horizontal movement mechanism 13 by the elevating mechanism 14. When the elevating mechanism 14 raises the pair of transfer arms 11 at the transfer operation position, a total of four lift pins 12 pass through the through holes 79 (see FIGS. 2 and 3) formed in the susceptor 74, and the lift pins The upper end of 12 protrudes from the upper surface of the susceptor 74. On the other hand, when the elevating mechanism 14 lowers the pair of transfer arms 11 at the transfer operation position, the lift pin 12 is pulled out from the through hole 79, and the horizontal movement mechanism 13 moves the pair of transfer arms 11 so as to open each. The transfer arm 11 moves to the retracted position. The retracted position of the pair of transfer arms 11 is directly above the base ring 71 of the holding portion 7. Since the base ring 71 is placed on the bottom surface of the recess 62, the retracted position of the transfer arm 11 is inside the recess 62. An exhaust mechanism (not shown) is also provided in the vicinity of the portion where the drive unit (horizontal movement mechanism 13 and elevating mechanism 14) of the transfer mechanism 10 is provided, and the atmosphere around the drive unit of the transfer mechanism 10 is provided. Is configured to be discharged to the outside of the chamber 6.

Returning to FIG. 1, the flash heating unit 5 provided above the chamber 6 is a light source composed of a plurality of (30 in this embodiment) xenon flash lamp FL inside the housing 51, and above the light source. It is configured to include a reflector 52 provided so as to cover the above. Further, a lamp light emitting window 53 is attached to the bottom of the housing 51 of the flash heating unit 5. The lamp light emitting window 53 constituting the floor portion of the flash heating unit 5 is a plate-shaped quartz window made of quartz. By installing the flash heating unit 5 above the chamber 6, the lamp light emitting window 53 faces the upper chamber window 63. The flash lamp FL irradiates the heat treatment space 65 with flash light from above the chamber 6 through the lamp light emitting window 53 and the upper chamber window 63.

Each of the plurality of flash lamps FL is a rod-shaped lamp having a long cylindrical shape, and the longitudinal direction thereof is along the main surface of the semiconductor wafer W held by the holding portion 7 (that is, along the horizontal direction). They are arranged in a plane so as to be parallel to each other. Therefore, the plane formed by the arrangement of the flash lamp FL is also a horizontal plane. The region where the plurality of flash lamps FL are arranged is larger than the plane size of the semiconductor wafer W.

The xenon flash lamp FL has a cylindrical glass tube (discharge tube) in which xenon gas is sealed inside and an anode and a cathode connected to a condenser are arranged at both ends thereof, and on the outer peripheral surface of the glass tube. It is provided with an attached trigger electrode. Since xenon gas is electrically an insulator, even if electric charges are accumulated in the condenser, electricity does not flow in the glass tube under normal conditions. However, when a high voltage is applied to the trigger electrode to break the insulation, the electricity stored in the capacitor instantly flows into the glass tube, and light is emitted by the excitation of xenon atoms or molecules at that time. In such a xenon flash lamp FL, the electrostatic energy stored in the capacitor in advance is converted into an extremely short optical pulse of 0.1 millisecond to 100 millisecond, so that the halogen lamp HL is continuously lit. It has the feature that it can irradiate extremely strong light compared to a light source. That is, the flash lamp FL is a pulse light emitting lamp that instantaneously emits light in an extremely short time of less than 1 second. The light emission time of the flash lamp FL can be adjusted by the coil constant of the lamp power supply that supplies power to the flash lamp FL.

Further, the reflector 52 is provided above the plurality of flash lamps FL so as to cover all of them. The basic function of the reflector 52 is to reflect the flash light emitted from the plurality of flash lamps FL toward the heat treatment space 65. The reflector 52 is made of an aluminum alloy plate, and its surface (the surface facing the flash lamp FL) is roughened by blasting.

The halogen heating unit 4 provided below the chamber 6 contains a plurality of halogen lamps HL (40 in this embodiment) inside the housing 41. The halogen heating unit 4 heats the semiconductor wafer W by irradiating the heat treatment space 65 with light from below the chamber 6 through the lower chamber window 64 by a plurality of halogen lamps HL.

FIG. 7 is a plan view showing the arrangement of a plurality of halogen lamps HL. The 40 halogen lamps HL are arranged in two upper and lower stages. Twenty halogen lamps HL are arranged in the upper stage near the holding portion 7, and 20 halogen lamps HL are also arranged in the lower stage farther from the holding portion 7 than in the upper stage. 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 stages are arranged so that their longitudinal directions are parallel to each other along the main surface of the semiconductor wafer W held by the holding portion 7 (that is, along the horizontal direction). There is. Therefore, the plane formed by the arrangement of the halogen lamps HL in both the upper and lower stages is a horizontal plane.

Further, as shown in FIG. 7, the arrangement density of the halogen lamp HL in the region facing the peripheral edge portion is higher than the region facing the central portion of the semiconductor wafer W held by the holding portion 7 in both the upper and lower stages. There is. That is, in both the upper and lower stages, the arrangement pitch of the halogen lamp HL is shorter in the peripheral portion than in the central portion of the lamp arrangement. Therefore, it is possible to irradiate a peripheral portion of the semiconductor wafer W, which tends to have a temperature drop during heating by light irradiation from the halogen heating unit 4, with a larger amount of light.

Further, the lamp group composed of the halogen lamp HL in the upper stage and the lamp group composed of the halogen lamp HL in the lower stage 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 in the upper stage and the longitudinal direction of the 20 halogen lamps HL arranged in the lower stage are orthogonal to each other. There is.

The halogen lamp HL is a filament type light source that incandescents the filament and emits light by energizing the filament arranged inside the glass tube. Inside the glass tube, a gas in which a small amount of a halogen element (iodine, bromine, etc.) is introduced into an inert gas such as nitrogen or argon is sealed. By introducing the halogen element, it becomes possible to set the temperature of the filament to a high temperature while suppressing the breakage of the filament. Therefore, the halogen lamp HL has a characteristic that it has a longer life and can continuously irradiate strong light as compared with a normal incandescent lamp. That is, the halogen lamp HL is a continuously lit lamp that continuously emits light for at least 1 second or longer. Further, since the halogen lamp HL is a rod-shaped lamp, it has a long life, and by arranging the halogen lamp HL along the horizontal direction, the radiation efficiency to the upper semiconductor wafer W becomes excellent.

Further, a reflector 43 is also provided under the two-stage halogen lamp HL in the housing 41 of the halogen heating unit 4 (FIG. 1). The reflector 43 reflects the light emitted from the plurality of halogen lamps HL toward the heat treatment space 65.

The control unit 3 controls the various operation mechanisms provided in the heat treatment apparatus 1. The configuration of the control unit 3 as hardware is the same as that of a general computer. That is, the control unit 3 stores a CPU, which is a circuit that performs various arithmetic processes, a ROM, which is a read-only memory for storing basic programs, a RAM, which is a read / write memory for storing various information, and control software and data. It has a magnetic disk to store. The processing in the heat treatment apparatus 1 proceeds when the CPU of the control unit 3 executes a predetermined processing program.

In addition to the above configuration, the heat treatment apparatus 1 prevents an excessive temperature rise of the halogen heating unit 4, the flash heating unit 5, and the chamber 6 due to the heat energy generated from the halogen lamp HL and the flash lamp FL during the heat treatment of the semiconductor wafer W. Therefore, it has various cooling structures. For example, a water cooling pipe (not shown) is provided on the wall of the chamber 6. Further, the halogen heating unit 4 and the flash heating unit 5 have an air-cooled structure in which a gas flow is formed inside to exhaust heat. In addition, air is also supplied to the gap between the upper chamber window 63 and the lamp light radiating window 53 to cool the flash heating unit 5 and the upper chamber window 63.

Next, the processing operation in the heat treatment apparatus 1 will be described. Here, a typical heat treatment operation for a normal semiconductor wafer (product wafer) W as a product will be described. The processing procedure of the semiconductor wafer W described below proceeds by the control unit 3 controlling each operation mechanism of the heat treatment apparatus 1.

First, prior to the processing of the semiconductor wafer W, the valve 84 for air supply is opened, and the valve 89 for exhaust is opened to start air supply / exhaust to the inside of the chamber 6. When the valve 84 is opened, nitrogen gas is supplied to the heat treatment space 65 from the gas supply hole 81. When the valve 89 is opened, the gas in the chamber 6 is exhausted from the gas exhaust hole 86. As a result, the nitrogen gas supplied from the upper part of the heat treatment space 65 in the chamber 6 flows downward and is exhausted from the lower part of the heat treatment space 65.

Subsequently, the gate valve 185 is opened to open the transfer opening 66, and the semiconductor wafer W to be processed is carried into the heat treatment space 65 in the chamber 6 through the transfer opening 66 by the transfer robot outside the apparatus. At this time, there is a possibility that the atmosphere outside the apparatus may be involved with the loading of the semiconductor wafer W, but since the nitrogen gas continues to be supplied to the chamber 6, the nitrogen gas flows out from the transport opening 66, and such a situation occurs. It is possible to minimize the entrainment of an external atmosphere.

The semiconductor wafer W carried in by the transfer robot advances to a position directly above the holding portion 7 and stops. 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, so that the lift pin 12 protrudes from the upper surface of the holding plate 75 of the susceptor 74 through the through hole 79. Receives the semiconductor wafer W. At this time, the lift pin 12 rises above the upper end of the substrate support pin 77.

After the semiconductor wafer W is placed on the lift pin 12, the transfer robot exits the heat treatment space 65, and the transfer opening 66 is closed by the gate valve 185. Then, as the pair of transfer arms 11 descend, the semiconductor wafer W is handed over from the transfer mechanism 10 to the susceptor 74 of the holding portion 7 and held in a horizontal posture from below. The semiconductor wafer W is supported by a plurality of substrate support pins 77 erected on the holding plate 75 and held by the susceptor 74. Further, the semiconductor wafer W is held by the holding portion 7 with the patterned surface as the upper surface. A predetermined distance is formed between the back surface (main surface opposite to the front surface) of the semiconductor wafer W supported by the plurality of substrate support pins 77 and the holding surface 75a of the holding plate 75. The pair of transfer arms 11 lowered to the lower side of the susceptor 74 are retracted to the retracted position, that is, inside the recess 62 by the horizontal moving mechanism 13.

After the semiconductor wafer W is held from below in a horizontal position by the susceptor 74 of the holding portion 7 made of quartz, the 40 halogen lamps HL of the halogen heating portion 4 are turned on all at once for preheating (assist heating). ) Is started. The halogen light emitted from the halogen lamp HL passes through the lower chamber window 64 and the susceptor 74 made of quartz and irradiates the lower surface of the semiconductor wafer W. By receiving the light irradiation from the halogen lamp HL, the semiconductor wafer W is preheated and the temperature rises. Since the transfer arm 11 of the transfer mechanism 10 is retracted inside the recess 62, it does not interfere with heating by the halogen lamp HL.

The temperature of the semiconductor wafer W, which is raised by irradiation with light from the halogen lamp HL, is measured by the 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 lamp HL while monitoring whether or not the temperature of the semiconductor wafer W, which is raised by light irradiation from the halogen lamp HL, has reached a predetermined preheating temperature T1. That is, the control unit 3 feedback-controls the output of the halogen lamp HL so that the temperature of the semiconductor wafer W becomes the preheating temperature T1 based on the measured value by the radiation thermometer 20.

After the temperature of the semiconductor wafer W reaches the preheating temperature T1, the control unit 3 maintains the semiconductor wafer W at the preheating temperature T1 for a while. Specifically, when the temperature of the semiconductor wafer W measured by the radiation thermometer 20 reaches the preheating temperature T1, the control unit 3 adjusts the output of the halogen lamp HL to substantially reserve the temperature of the semiconductor wafer W. The heating temperature is maintained at T1.

When the temperature of the semiconductor wafer W reaches the preheating temperature T1 and a predetermined time elapses, the flash lamp FL of the flash heating unit 5 irradiates the surface of the semiconductor wafer W held by the susceptor 74 with flash light. At this time, a part of the flash light radiated from the flash lamp FL goes directly into the chamber 6, and the other part is once reflected by the reflector 52 and then goes into the chamber 6, and these flash lights The semiconductor wafer W is flash-heated by irradiation.

Since the flash heating is performed by irradiating the flash light (flash) from the flash lamp FL, the surface temperature of the semiconductor wafer W can be raised in a short time. That is, the flash light emitted from the flash lamp FL has an extremely short irradiation time of 0.1 millisecond or more and 100 millisecond or less, in which the electrostatic energy stored in the capacitor in advance is converted into an extremely short optical pulse. It is a strong flash. Then, the surface temperature of the semiconductor wafer W, which is flash-heated by the flash light irradiation from the flash lamp FL, momentarily rises to the processing temperature T2 of 1000 ° C. or higher, and then rapidly falls.

After the flash heat treatment is completed, the halogen lamp HL is turned off after a lapse of a predetermined time. As a result, the semiconductor wafer W rapidly drops from the preheating temperature T1. The temperature of the semiconductor wafer W during cooling is measured by the radiation thermometer 20, and the measurement result is transmitted to the control unit 3. The control unit 3 monitors whether or not the temperature of the semiconductor wafer W has dropped to a predetermined temperature based on the measurement result of the radiation thermometer 20. Then, after the temperature of the semiconductor wafer W is lowered to a predetermined value or less, the pair of transfer arms 11 of the transfer mechanism 10 horizontally move from the retracted position to the transfer operation position again and rise, so that the lift pin 12 is a susceptor. The semiconductor wafer W that protrudes from the upper surface of 74 and has been heat-treated is received from the susceptor 74. Subsequently, the transfer opening 66 closed by the gate valve 185 is opened, the semiconductor wafer W mounted on the lift pin 12 is carried out from the chamber 6 by a transfer robot outside the apparatus, and the semiconductor wafer W is heat-treated. Complete.

A part of the lower surface of the susceptor 74 (strictly speaking, the lower surface of the holding plate 75 of the susceptor 74) that supports the semiconductor wafer W heated by light irradiation is roughened. Hereinafter, the procedure for roughening the susceptor 74 will be described.

First, the in-plane temperature distribution generated in the semiconductor wafer W when light irradiation is performed from the halogen lamp HL in a state where the semiconductor wafer W is supported on the susceptor 74 which has not been roughened at all is obtained. The halogen lamp HL irradiates the upper surface of the halogen lamp HL with light from below the susceptor 74 that supports the semiconductor wafer W. The light emitted from the halogen lamp HL passes through the quartz susceptor 74 and irradiates the back surface of the semiconductor wafer W. The semiconductor wafer W is heated and raised in temperature by being irradiated with light from the halogen lamp HL. At this time, an in-plane temperature distribution is generated in the semiconductor wafer W. Then, the in-plane temperature distribution generated on the semiconductor wafer W is acquired. The in-plane temperature distribution may be obtained by irradiating the semiconductor wafer W actually supported by the susceptor 74 with light from the halogen lamp HL, or may be obtained by simulation (subsequent in-plane temperature distribution). The same applies to the acquisition of).

FIG. 8 is a diagram showing an example of the in-plane temperature distribution generated on the semiconductor wafer W. The horizontal axis of the figure shows the distance from the center of the wafer along the radial direction of the semiconductor wafer W having a diameter of φ300 mm. The vertical axis of the figure shows the sheet resistance value of the semiconductor wafer W obtained as a result of the heat treatment (same in FIGS. 11, 14, 17, and 20). The smaller the sheet resistance value, the higher the temperature of the semiconductor wafer W. That is, in FIG. 8, the semiconductor wafer W has a higher temperature toward the lower side.

As shown in FIG. 8, when the semiconductor wafer W supported on the susceptor 74 which has not been roughened at all is irradiated with light from the halogen lamp HL, the vicinity of the central portion of the semiconductor wafer W is heated to a high temperature. On the other hand, the peripheral part tends to be relatively cold. That is, it cannot be said that the in-plane temperature distribution generated on the semiconductor wafer W is uniform.

In the temperature distribution shown in FIG. 8, since the vicinity of the central portion of the semiconductor wafer W is heated to a high temperature equal to or higher than a predetermined temperature, as shown in FIG. 10, the center of the lower surface of the susceptor 74 facing the central portion of the semiconductor wafer W. The portion area 91 is roughened. That is, a part of the surface of the susceptor 74 facing the high temperature region of the semiconductor wafer W whose temperature is equal to or higher than the predetermined temperature in the temperature distribution of FIG. 8 is roughened. The roughening process may be performed by, for example, sandblasting. By making the central region 91 on the lower surface of the susceptor 74 a rough surface, the light transmittance of the central region 91 is lower than that of the other regions. Note that FIG. 10 is a plan view of the susceptor 74 as viewed from below, but the opening 78 and the through hole 79 are not shown (the same applies to FIGS. 13, 16 and 19).

FIG. 9 is a diagram showing the effect of the roughening process in FIG. The horizontal axis of the figure shows the distance from the center of the wafer along the radial direction of the semiconductor wafer W having a diameter of φ300 mm. The vertical axis of the figure shows the amount of increase in the sheet resistance value (same in FIGS. 12, 15 and 18). Since the central region 91 on the lower surface of the susceptor 74 is a rough surface, the amount of light that reaches the vicinity of the central portion of the semiconductor wafer W decreases when light is irradiated from the halogen lamp HL, and the central portion thereof. The temperature in the vicinity decreases (that is, the sheet resistance value increases). The amount of increase in the sheet resistance value can be adjusted by the size and roughness of the central region 91 which is regarded as a rough surface.

Next, the in-plane temperature distribution generated on the semiconductor wafer W when light irradiation is performed from the halogen lamp HL while the semiconductor wafer W is supported on the susceptor 74 subjected to the roughening process as shown in FIG. 10 is obtained. .. The light emitted from the halogen lamp HL passes through the susceptor 74 and irradiates the back surface of the semiconductor wafer W. However, since the transmittance of the central region 91 is low, the light emitted from the halogen lamp HL is in the vicinity of the central portion of the semiconductor wafer W. The illuminance decreases and the temperature near the center becomes relatively low.

FIG. 11 is a diagram showing an example of the in-plane temperature distribution generated in the semiconductor wafer W supported on the susceptor 74 subjected to the roughening process as shown in FIG. As shown in FIG. 11, when the semiconductor wafer W supported by the susceptor 74 whose central region 91 is a rough surface is irradiated with light from the halogen lamp HL, it is closer to the center of the semiconductor wafer W as compared with FIG. The temperature is low. That is, the in-plane temperature distribution in FIG. 11 is roughly a composite of FIG. 9 with the in-plane temperature distribution in FIG.

As shown in FIG. 13, the region 92 on the lower surface of the susceptor 74 facing the high temperature region of the semiconductor wafer W whose temperature is equal to or higher than the predetermined temperature in the temperature distribution of FIG. 11 is roughened. The region 92 is an annular region that surrounds the central region 91. In FIG. 13, the central region 91 on the lower surface of the susceptor 74 and the region 92 surrounding the central region 91 are rough surfaces.

FIG. 12 is a diagram showing the effect of the new roughening process (effect of the region 92) in FIG. Since the region 92 on the lower surface of the susceptor 74 is a rough surface, the temperature of the portion of the semiconductor wafer W facing the region 92 decreases when light is irradiated from the halogen lamp HL. The amount of decrease in temperature can be adjusted by the width and roughness of the region 92 to be a rough surface.

Next, the in-plane temperature distribution generated on the semiconductor wafer W when light irradiation is performed from the halogen lamp HL while the semiconductor wafer W is supported on the susceptor 74 subjected to the roughening process as shown in FIG. 13 is obtained. .. FIG. 14 is a diagram showing an example of the in-plane temperature distribution generated in the semiconductor wafer W supported on the susceptor 74 subjected to the roughening process as shown in FIG. As shown in FIG. 14, when the semiconductor wafer W supported by the susceptor 74 having the central region 91 and the region 92 as a rough surface is irradiated with light from the halogen lamp HL, the central region 91 and the region 92 are exposed to the light. The temperature of the portion of the semiconductor wafer W facing each other is relatively low. The in-plane temperature distribution of FIG. 14 is roughly a composite of FIG. 12 with the in-plane temperature distribution of FIG.

As shown in FIG. 16, a roughening process is performed on a region 93 on the lower surface of the susceptor 74 facing a high temperature region of the semiconductor wafer W whose temperature is equal to or higher than a predetermined temperature in the temperature distribution of FIG. The region 93 is an annular region that further surrounds the region 92. In FIG. 16, the central region 91, the region 92, and the region 93 on the lower surface of the susceptor 74 are rough surfaces.

FIG. 15 is a diagram showing the effect of the new roughening process (effect of the region 93) in FIG. Since the region 93 on the lower surface of the susceptor 74 is a rough surface, the temperature of the portion of the semiconductor wafer W facing the region 93 decreases when light is irradiated from the halogen lamp HL. The amount of decrease in temperature can be adjusted by the width and roughness of the region 93 to be a rough surface.

Similarly, the in-plane temperature distribution generated on the semiconductor wafer W when light irradiation is performed from the halogen lamp HL while the semiconductor wafer W is supported on the susceptor 74 subjected to the roughening process as shown in FIG. 16 is obtained. .. FIG. 17 is a diagram showing an example of the in-plane temperature distribution generated in the semiconductor wafer W supported on the susceptor 74 subjected to the roughening process as shown in FIG. As shown in FIG. 17, when the semiconductor wafer W supported by the susceptor 74 having the central region 91, the region 92 and the region 93 as a rough surface is irradiated with light from the halogen lamp HL, the central region 91, The temperature of the portion of the semiconductor wafer W facing the region 92 and the region 93 is relatively low. The in-plane temperature distribution of FIG. 17 is roughly a composite of FIG. 15 with the in-plane temperature distribution of FIG.

In the temperature distribution shown in FIG. 17, since the vicinity of the peripheral edge portion of the semiconductor wafer W is heated to a high temperature equal to or higher than a predetermined temperature, as shown in FIG. 19, the peripheral edge of the lower surface of the susceptor 74 facing the peripheral edge portion of the semiconductor wafer W. The portion region 94 is roughened. That is, the peripheral edge region 94 on the lower surface of the susceptor 74 facing the high temperature region of the semiconductor wafer W whose temperature is equal to or higher than the predetermined temperature in the temperature distribution of FIG. 17 is roughened. The peripheral edge region 94 is an annular region facing the peripheral edge of the semiconductor wafer W. In FIG. 19, the central region 91, the region 92, the region 93, and the peripheral region 94 on the lower surface of the susceptor 74 are rough surfaces.

FIG. 18 is a diagram showing the effect of the new roughening process (effect of the peripheral region 94) in FIG. Since the peripheral edge region 94 on the lower surface of the susceptor 74 is a rough surface, the temperature of the peripheral edge portion of the semiconductor wafer W facing the peripheral edge region 94 is lowered when light is irradiated from the halogen lamp HL. The amount of decrease in temperature can be adjusted by the width and roughness of the peripheral edge region 94 to be a rough surface.

FIG. 20 shows the in-plane temperature distribution generated on the semiconductor wafer W when light is irradiated from the halogen lamp HL while the semiconductor wafer W is supported on the susceptor 74 subjected to the roughening process as shown in FIG. It is a figure which shows an example. As shown in FIG. 20, when the semiconductor wafer W supported by the susceptor 74 having the central region 91, the region 92, the region 93 and the peripheral region 94 as rough surfaces is irradiated with light from the halogen lamp HL, they are used. The temperature of the portion of the semiconductor wafer W facing the central region 91, the region 92, the region 93, and the peripheral region 94 is relatively low. The in-plane temperature distribution of FIG. 20 is roughly a composite of FIG. 18 with the in-plane temperature distribution of FIG.

As is clear from a comparison between FIGS. 8 and 20, when the semiconductor wafer W is supported on the susceptor 74 in which the rough surface region as shown in FIG. 19 is formed and light is irradiated from the halogen lamp HL, the semiconductor The in-plane temperature distribution generated on the wafer W becomes remarkably uniform. As a result, the in-plane temperature distribution of the semiconductor wafer W becomes uniform during the preheating by the halogen lamp HL, and then a good flash heat treatment can be performed.

In the present embodiment, a step of acquiring the in-plane temperature distribution generated on the semiconductor wafer W when the semiconductor wafer W supported by the susceptor 74 is irradiated with light from the halogen lamp HL, and a predetermined temperature or higher in the in-plane temperature distribution. The step of roughening a part of the surface of the susceptor 74 facing the high temperature region of the semiconductor wafer W is repeated a plurality of times. As a result, as shown in FIG. 19, a plurality of rough surface regions are formed on the lower surface of the susceptor 74. Then, by supporting the semiconductor wafer W on the susceptor 74 as shown in FIG. 19 and irradiating the semiconductor wafer W with light from the halogen lamp HL, the illuminance in the high temperature region of the semiconductor wafer W is reduced, and the in-plane temperature distribution of the semiconductor wafer W is reduced. Uniformity can be improved.

The same effect can be expected even if a rough surface region is provided on another quartz member existing between the semiconductor wafer W and the halogen lamp HL, for example, the lower chamber window 64, but the distance from the semiconductor wafer W is shorter. If the susceptor 74 is provided with a rough surface region, the in-plane temperature distribution of the semiconductor wafer W can be made uniform with higher accuracy.

Although the embodiments of the present invention have been described above, the present invention can be modified in various ways other than those described above as long as the gist of the present invention is not deviated. For example, in the above embodiment, the step of acquiring the temperature distribution of the semiconductor wafer W supported by the susceptor 74 and the step of roughening a part of the region of the susceptor 74 based on the temperature distribution are performed four times. Again, this is not the only limitation. The number of times both steps are repeated may be more than four times, less than four times, and at least once. As the number of times both steps are repeated increases, the uniformity of the in-plane temperature distribution of the semiconductor wafer W when irradiating light from the halogen lamp HL can be improved, but the work becomes complicated.

Further, the roughness of the rough surface may be made different according to the height of the temperature in the in-plane temperature distribution generated in the semiconductor wafer W. Specifically, the higher the temperature in the high temperature region of the semiconductor wafer W, the rougher the surface roughness of the portion of the susceptor 74 facing the position where the temperature rises. In this way, as the temperature in the high temperature region of the semiconductor wafer W becomes higher, the transmittance of the portion of the susceptor 74 facing the position where the temperature becomes higher becomes lower, and the temperature of the semiconductor wafer W at that position is further lowered. Will be done. As a result, the uniformity of the in-plane temperature distribution of the semiconductor wafer W can be improved with higher accuracy.

Further, in the above embodiment, the lower surface of the susceptor 74 is roughened, but instead of this, the upper surface of the susceptor 74 may be roughened. Even if the upper surface of the susceptor 74 is roughened, the uniformity of the in-plane temperature distribution of the semiconductor wafer W can be improved by the same action and effect as in the above embodiment. However, if the upper surface of the susceptor 74 is a rough surface, the supported semiconductor wafer W and the rough surface may rub against each other to generate particles. Therefore, it is preferable that the lower surface of the susceptor 74 is a rough surface as in the above embodiment. ..

Further, instead of making the peripheral edge region 94 on the lower surface of the susceptor 74 a rough surface, a quartz ring-shaped member is provided in the peripheral edge region 94 on the upper surface of the susceptor 74, and the semiconductor wafer W is supported by the ring-shaped member. You may do so. As a result, the portion of the semiconductor wafer W facing the peripheral edge region 94 is cooled by the quartz ring-shaped member, and the same effect as when the peripheral edge region 94 is made a rough surface can be obtained.

Further, in the above embodiment, the flash heating unit 5 is provided with 30 flash lamp FLs, but the present invention is not limited to this, and the number of flash lamp FLs can be any number. .. Further, the flash lamp FL is not limited to the xenon flash lamp, and may be a krypton flash lamp. Further, the number of halogen lamps HL provided in the halogen heating unit 4 is not limited to 40, and can be any number.

Further, in the above embodiment, the semiconductor wafer W is preheated by using a filament type halogen lamp HL as a continuous lighting lamp that continuously emits light for 1 second or longer, but the present invention is not limited to this. Instead of the halogen lamp HL, a discharge type arc lamp (for example, a xenon arc lamp) may be used as a continuous lighting lamp to perform preheating.

Further, the substrate to be processed by the heat treatment apparatus 1 is not limited to the semiconductor wafer, and may be a glass substrate used for a flat panel display such as a liquid crystal display device or a substrate for a solar cell.

1 Heat treatment equipment 3 Control unit 4 Halogen heating unit 5 Flash heating unit 6 Chamber 7 Holding unit 10 Transfer mechanism 20 Radiation thermometer 65 Heat treatment space 74 Suceptor 75 Holding plate 78 Opening 77 Board support pin 91 Central area 92, 93 area 94 Peripheral area FL flash lamp HL halogen lamp W semiconductor wafer

Claims (8)

A method for manufacturing a susceptor that supports a substrate that is heated by light irradiation.
A temperature distribution acquisition step of acquiring the temperature distribution generated on the substrate when the substrate supported by the susceptor is irradiated with light from below the susceptor.
A roughening processing step of roughening a part of the surface of the susceptor facing the high temperature region of the substrate whose temperature is equal to or higher than a predetermined temperature in the temperature distribution.
A method for manufacturing a susceptor, which comprises. In the method for manufacturing a susceptor according to claim 1,
A method for manufacturing a susceptor, which comprises repeating the temperature distribution acquisition step and the roughening processing step a plurality of times. In the method for manufacturing a susceptor according to claim 1 or 2.
A method for producing a susceptor, which comprises roughening the surface roughness of a portion of the susceptor facing a position where the temperature rises as the temperature in the high temperature region of the substrate increases. In the method for manufacturing a susceptor according to any one of claims 1 to 3.
A method for manufacturing a susceptor, wherein the lower surface of the susceptor is a rough surface. A susceptor that supports a substrate that is heated by light irradiation.
When the substrate supported by the susceptor is irradiated with light from below the susceptor, the temperature distribution generated on the substrate is coarse on a part of the surface of the susceptor facing the high temperature region of the substrate. A susceptor characterized in that a surface is formed. In the susceptor according to claim 5,
The susceptor is characterized in that the higher the temperature in the high temperature region of the substrate, the rougher the surface roughness of the portion of the susceptor facing the position where the temperature becomes higher. In the susceptor according to claim 5 or 6.
A susceptor characterized in that a rough surface is formed on the lower surface of the susceptor. A heat treatment apparatus that heats a substrate by irradiating the substrate with light.
A chamber for accommodating the substrate and
The susceptor according to any one of claims 5 to 7, which is provided in the chamber and supports the substrate.
A continuous lighting lamp that heats the substrate by irradiating light from below the susceptor,
A heat treatment apparatus comprising.

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