JP2019036645A - Heat treatment device - Google Patents

Abstract

To provide a heat treatment device configured to allow treatment gas to flow evenly in a chamber.SOLUTION: A gate valve-side exhaust port 150 and a main exhaust port 160 which exhaust gas in a chamber 6 are provided at a side wall of the chamber 6. On the chamber 6 is mounted an annular-shape exhaust ring 90 so as to cover the gate valve-side exhaust port 150 and the main exhaust port 160. A plurality of exhaust ports are drilled in the exhaust ring 90. Aperture ratios of the plurality of exhaust ports become higher as the ports separate away from the gate valve-side exhaust valve port 150 and the main exhaust port 160 along a circumferential direction of the exhaust ring 90. This causes negative pressure having nearly equal strength to be applied to all of the plurality of exhaust ports provided in the exhaust ring 90, so that gas in the chamber 6 is exhausted at an even flow rate over the whole circumference of the exhaust ring 90 and treatment gas can be flown evenly in the chamber 6.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a heat treatment apparatus for heating a thin plate-shaped precision electronic substrate (hereinafter simply referred to as “substrate”) such as a semiconductor wafer by irradiating light.

  In the semiconductor device manufacturing process, impurity introduction is an indispensable step for forming a pn junction in a semiconductor wafer. Currently, impurities are generally introduced by ion implantation and subsequent annealing. The ion implantation method is a technique in which impurity elements such as boron (B), arsenic (As), and phosphorus (P) are ionized and collided with a semiconductor wafer at a high acceleration voltage to physically perform impurity implantation. The implanted impurities are activated by annealing. At this time, if the annealing time is about several seconds or more, the implanted impurities are deeply diffused by heat, and as a result, the junction depth becomes deeper than required, and there is a possibility that good device formation may be hindered.

  Therefore, in recent years, flash lamp annealing (FLA) has attracted attention as an annealing technique for heating a semiconductor wafer in an extremely short time. Flash lamp annealing is a semiconductor wafer in which impurities are implanted by irradiating the surface of the semiconductor wafer with flash light using a xenon flash lamp (hereinafter, simply referred to as “flash lamp” means xenon flash lamp). Is a heat treatment technique for raising the temperature of only the surface of the material in a very short time (several milliseconds or less).

  The radiation spectral distribution of a xenon flash lamp ranges from the ultraviolet region to the near infrared region, has a shorter wavelength than the conventional halogen lamp, and almost coincides with the fundamental absorption band of a silicon semiconductor wafer. Therefore, when the semiconductor wafer is irradiated with flash light from the xenon flash lamp, the semiconductor wafer can be rapidly heated with little transmitted light. Further, it has been found that if the flash light irradiation is performed for a very short time of several milliseconds or less, only the vicinity of the surface of the semiconductor wafer can be selectively heated. For this reason, if the temperature is raised for a very short time by the xenon flash lamp, only the impurity activation can be performed without deeply diffusing the impurities.

  In a heat treatment apparatus using a xenon flash lamp, flash light having extremely high energy is instantaneously irradiated onto the surface of the semiconductor wafer, so that the surface temperature of the semiconductor wafer rises rapidly in an instant. As a result, a rapid thermal expansion occurs on the surface of the semiconductor wafer, causing deformation, and the semiconductor wafer vibrates or jumps on the susceptor during flash light irradiation. Then, sliding with the susceptor accompanying the vibration (or jumping) of the semiconductor wafer and turbulence of the air flow generate particles in the chamber, which adhere to the semiconductor wafer and contaminate the semiconductor wafer.

  For this reason, Patent Document 1 proposes a technology for efficiently discharging the generated particles from the chamber and preventing the particles from adhering to the semiconductor wafer by increasing the flow rate of nitrogen gas supplied into the chamber. ing.

JP 2013-207033 A

  However, increasing the flow rate of nitrogen gas supplied into the chamber is effective in reducing the number of particles, but the flow of processing gas in the chamber becomes non-uniform, and the temperature distribution of the semiconductor wafer There has been a problem of lowering the internal uniformity.

Further, depending on the processing content of the flash lamp annealing, a reactive gas such as ammonia (NH ₃ ) or forming gas may be supplied into the chamber. Typically, the reactive gas is supplied into the chamber at a relatively small flow rate. However, in order to maintain the reaction uniformity in the plane of the semiconductor wafer, the supply at a low flow rate may be used. It is desirable for the processing gas to flow uniformly in the chamber.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a heat treatment apparatus capable of flowing a processing gas uniformly in a chamber.

  In order to solve the above-mentioned problems, a first aspect of the present invention is a heat treatment apparatus for heating a substrate by irradiating the substrate with light, and a chamber having a substantially cylindrical side wall, and the substrate is held in the chamber. A holding unit, a light irradiation unit for irradiating light to the substrate held by the holding unit, a gas supply unit for supplying a processing gas into the chamber, and loading / unloading of the substrate into / from the chamber among the side walls. A first exhaust port for exhausting the gas in the chamber provided on the furnace opening side, and a second exhaust port for exhausting the gas in the chamber provided on the side of the side wall opposite to the first exhaust port. An exhaust port is attached to the side wall so as to cover the first exhaust port and the second exhaust port, and the gas in the chamber is transferred to the first exhaust port and the second exhaust port. A ring-shaped exhaust ring leading to a port, the exhaust ring including a plurality of exhaust ports for sucking the gas in the chamber, the plurality of exhaust ports, the first exhaust port, and the second exhaust port A ring-shaped buffer portion that communicates with a port and allows the gas sucked from the plurality of exhaust ports to flow to the first exhaust port and the second exhaust port along the circumferential direction of the exhaust ring, The opening ratio of the plurality of exhaust ports is higher as the distance from the first exhaust port and the second exhaust port along the circumferential direction of the exhaust ring is longer.

  According to a second aspect of the present invention, in the heat treatment apparatus according to the first aspect of the present invention, the aperture ratio of the plurality of exhaust ports is such that the first exhaust port and the second exhaust port are arranged along a circumferential direction of the exhaust ring. It is characterized by being highest at a part 90 ° away from the center.

  According to a third aspect of the invention, in the heat treatment apparatus according to the first or second aspect of the invention, a first exhaust pipe connected to the first exhaust port and a second exhaust pipe connected to the second exhaust port. An exhaust pipe, a first conductance adjustment valve that is provided in the first exhaust pipe and adjusts the pressure loss of the first exhaust pipe, and is provided in the second exhaust pipe and adjusts the pressure loss of the second exhaust pipe. A second conductance adjustment valve that performs the first exhaust by the first conductance adjustment valve and the second conductance adjustment valve when the substrate is carried into and out of the chamber through the furnace port. The exhaust flow rate from the port is made larger than the exhaust flow rate from the second exhaust port.

  According to a fourth aspect of the present invention, in a heat treatment apparatus for heating a substrate by irradiating the substrate with light, a chamber having a substantially cylindrical side wall, a holding unit for holding the substrate in the chamber, A light irradiation unit for irradiating light to the substrate held by a holding unit, a gas supply unit for supplying a processing gas into the chamber, and an exhaust for exhausting the gas in the chamber provided in a part of the side wall And a ring-shaped exhaust ring that is attached to the side wall so as to cover the exhaust port and guides the gas in the chamber to the exhaust port, and the exhaust ring sucks the gas in the chamber A plurality of exhaust ports that communicate with each other, the exhaust ports and the exhaust ports communicating with each other, and gas sucked from the plurality of exhaust ports along the circumferential direction of the exhaust ring. And a buffer portion of the annular shape to flow in, the aperture ratio of the plurality of exhaust ports, characterized in that increases as the distance from the exhaust port along the circumferential direction of the exhaust ring becomes longer.

  According to the first to third aspects of the present invention, the opening ratio of the plurality of exhaust ports becomes higher as the distance from the first exhaust port and the second exhaust port along the circumferential direction of the exhaust ring increases. A negative pressure of approximately the same level acts on all of the exhaust ports of the gas, and the gas in the chamber is exhausted at a uniform flow rate over the entire circumference of the exhaust ring, and the processing gas is allowed to flow uniformly in the chamber. be able to.

  In particular, according to the third aspect of the present invention, when the substrate is carried into and out of the chamber via the furnace port, the exhaust flow rate from the first exhaust port is controlled by the first conductance adjustment valve and the second conductance adjustment valve. Since the exhaust flow rate from the two exhaust ports is increased, particles flowing from the furnace port as the substrate is carried in / out can be effectively discharged.

  According to the invention of claim 4, the opening ratio of the plurality of exhaust ports becomes higher as the distance from the exhaust port along the circumferential direction of the exhaust ring increases, so that the strength of the plurality of exhaust ports is substantially the same for all the exhaust ports. This negative pressure acts, and the gas in the chamber is exhausted at a uniform flow rate over the entire circumference of the exhaust ring, so that the processing gas can flow uniformly in the chamber.

It is a longitudinal cross-sectional view which shows the structure of the heat processing apparatus which concerns on this invention. It is a perspective view which shows the whole external appearance of a holding | maintenance part. It is a top view of a susceptor. It is sectional drawing of a susceptor. It is a top view of a transfer mechanism. It is a side view of a transfer mechanism. It is a top view which shows arrangement | positioning of a some halogen lamp. It is a perspective view which shows the external appearance of an exhaust ring. It is a figure which shows typically the flow of the exhaust_gas | exhaustion from the chamber by an exhaust ring. It is a perspective view which shows the exhaust ring which provided the exhaust port of another shape.

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

  FIG. 1 is a longitudinal sectional view showing a configuration of a heat treatment apparatus 1 according to the present invention. A heat treatment apparatus 1 in FIG. 1 is a flash lamp annealing apparatus that heats a semiconductor wafer W by irradiating a disk-shaped semiconductor wafer W as a substrate with flash light irradiation. 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). Impurities are implanted into the semiconductor wafer W before being carried into the heat treatment apparatus 1, and an activation process of the impurities implanted by the heat treatment by the heat treatment apparatus 1 is executed. In FIG. 1 and the subsequent drawings, the size and number of each part are exaggerated or simplified as necessary for easy understanding.

  The heat treatment apparatus 1 includes a chamber 6 that accommodates a semiconductor wafer W, a flash heating unit 5 that houses a plurality of flash lamps FL, and a halogen heating unit 4 that houses 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. The heat treatment apparatus 1 includes a holding unit 7 that holds the semiconductor wafer W in a horizontal posture inside the chamber 6, and a transfer mechanism 10 that transfers the semiconductor wafer W between the holding unit 7 and the outside of the apparatus, Is provided. Furthermore, the heat treatment apparatus 1 includes a control unit 3 that controls the operation mechanisms provided in the halogen heating unit 4, the flash heating unit 5, and the chamber 6 to perform the heat treatment of the semiconductor wafer W.

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

  A reflection ring 68 is attached to the upper portion of the inner wall surface of the chamber side portion 61, and an exhaust ring 90 is attached to the lower portion. Both the exhaust ring 90 and the reflection ring 68 are formed in an annular shape. An inner space of the chamber 6, that is, a space surrounded by the upper chamber window 63, the lower chamber window 64, the chamber side portion 61, the reflection ring 68 and the exhaust ring 90 is defined as the heat treatment space 65.

  By attaching the reflection ring 68 and the exhaust ring 90 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 surrounded by a central portion of the inner wall surface of the chamber side portion 61 where the reflection ring 68 and the exhaust ring 90 are not mounted, a lower end surface of the reflection ring 68, and an upper end surface of the exhaust ring 90 is formed. Is done. 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 portion 61 and the reflection ring 68 are formed of a metal material (for example, stainless steel) having excellent strength and heat resistance.

  The chamber side 61 is formed with a transfer opening (furnace port) 66 for carrying the semiconductor wafer W into and out of the chamber 6. The transfer opening 66 can be opened and closed by a gate valve 185. The transport opening 66 is connected to the outer peripheral surface of the recess 62. Therefore, when the gate valve 185 opens the transfer opening 66, the semiconductor wafer W is carried into the heat treatment space 65 through the recess 62 from the transfer opening 66 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 transfer opening 66, the heat treatment space 65 in the chamber 6 becomes a sealed space.

  Further, a through hole 61 a 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 portion 61 where the through hole 61a is provided. The through hole 61 a is a cylindrical hole for guiding infrared light emitted from the lower surface of the semiconductor wafer W held by a susceptor 74 described later to the radiation thermometer 20. The through hole 61 a is provided to be inclined with respect to the horizontal direction so that the axis in the through direction intersects the main surface of the semiconductor wafer W held by 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 facing the heat treatment space 65.

A gas supply hole 81 for supplying a processing gas to the heat treatment space 65 is formed in the upper portion 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 connected to a gas supply pipe 83 through 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 a processing gas supply source 85. A supply valve 84 is inserted in the middle of the path of the gas supply pipe 83. When the supply valve 84 is opened, the processing gas is supplied from the processing gas supply source 85 to the buffer space 82. The processing gas flowing 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 processing 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 obtained by mixing them can be used. Nitrogen gas in the embodiment).

  A gate valve side exhaust port 150 and a main exhaust port 160 which are two exhaust ports for exhausting the gas in the heat treatment space 65 are formed in the lower portion of the inner wall of the chamber 6. The gate valve side exhaust port 150 and the main exhaust port 160 are both formed at positions below the recess 62. The gate valve side exhaust port (first exhaust port) 150 is provided on the side of the transfer opening 66 in the chamber side portion 61. On the other hand, the main exhaust port (second exhaust port) 160 is provided on the opposite side of the chamber side portion 61 from the gate valve side exhaust port 150. That is, the gate valve side exhaust port 150 and the main exhaust port 160 are provided 180 degrees apart so as to face each other in the radial direction of the cylindrical chamber side portion 61.

  A first exhaust pipe 151 is connected to the gate valve side exhaust port 150. A second exhaust pipe 161 is connected to the main exhaust port 160. The first exhaust pipe 151 and the second exhaust pipe 161 merge and are connected to the exhaust unit 190. In other words, the gate valve side exhaust port 150 and the main exhaust port 160 are connected to the common exhaust part 190 to apply a negative pressure. As the exhaust unit 190, for example, an exhaust utility of a factory where the vacuum pump or the heat treatment apparatus 1 is installed can be used.

  A first exhaust valve 152 and a first conductance adjustment valve 153 are inserted in the middle of the path of the first exhaust pipe 151. The first exhaust valve 152 is a valve for opening and closing the path of the first exhaust pipe 151 such as an electromagnetic valve. The first conductance adjustment valve 153 is a pressure control valve for adjusting the pressure loss of the first exhaust pipe 151. The first conductance adjustment valve 153 can adjust the negative pressure applied from the exhaust part 190 to the gate valve side exhaust port 150. Note that the first exhaust valve 152 and the first conductance adjustment valve 153 may be installed on the upstream side of the first exhaust pipe 151.

  A second exhaust valve 162 and a second conductance adjustment valve 163 are interposed in the middle of the path of the second exhaust pipe 161. Similar to the first exhaust valve 152, the second exhaust valve 162 is a valve for opening and closing the path of the second exhaust pipe 161. The second conductance adjustment valve 163 is a pressure control valve for adjusting the pressure loss of the second exhaust pipe 161. The second conductance adjustment valve 163 can adjust the negative pressure applied from the exhaust part 190 to the main exhaust port 160. Note that either the second exhaust valve 162 or the second conductance adjustment valve 163 may be located upstream of the second exhaust pipe 161.

  As shown in FIG. 1, an exhaust ring 90 is attached to the lower portion of the inner wall of the chamber 6 so as to cover the gate valve side exhaust port 150 and the main exhaust port 160. FIG. 8 is a perspective view showing the appearance of the exhaust ring 90. For convenience of explanation, FIG. 8 shows a semicircular portion of an annular exhaust ring 90. The exhaust ring 90 attached to the lower part of the inner wall surface of the substantially cylindrical chamber side portion 61 has an annular shape. A cross section of the annular exhaust ring 90 cut along the radial direction has a U-shape. In a state where the exhaust ring 90 is attached to the chamber 6, a buffer portion 95 is formed between the U-shaped inner portion of the exhaust ring 90 and the inner wall surface of the chamber side portion 61. The buffer part 95 is a cylindrical space formed between the exhaust ring 90 and the chamber side part 61.

  As shown in FIG. 8, the exhaust ring 90 has a plurality of exhaust ports 96 formed therein. In the present embodiment, each of the plurality of exhaust ports 96 is a round hole. The plurality of exhaust ports 96 are provided in a line on the wall surface of the exhaust ring 90 along the circumferential direction of the exhaust ring 90. The plurality of exhaust ports 96 are provided so as to face the heat treatment space 65 in the chamber 6. The plurality of exhaust ports 96, the gate valve side exhaust port 150, and the main exhaust port 160 are connected in communication via the buffer unit 95. Accordingly, the negative pressure applied to the gate valve side exhaust port 150 and the main exhaust port 160 by the exhaust unit 190 acts on the plurality of exhaust ports 96 via the buffer unit 95. Thereby, the gas in the chamber 6 is sucked from the plurality of exhaust ports 96 of the exhaust ring 90. The gas sucked from the plurality of exhaust ports 96 flows in the annular buffer portion 95 along the circumferential direction of the exhaust ring 90 and flows into the gate valve side exhaust port 150 and / or the main exhaust port 160.

  The opening ratio of the plurality of exhaust ports 96 increases as the distance from the gate valve side exhaust port 150 and the main exhaust port 160 along the circumferential direction of the exhaust ring 90 increases. The aperture ratio of the plurality of exhaust ports 96 is the area of the exhaust ports 96 per unit area on the wall surface of the exhaust ring 90. The higher the density of the plurality of exhaust ports 96, the higher the aperture ratio of the plurality of exhaust ports 96. In the present embodiment, the gate valve side exhaust port 150 and the main exhaust port 160 are provided 180 degrees apart so as to face both ends of the chamber 6 in the radial direction, and the gate along the circumferential direction of the exhaust ring 90 is provided. The opening ratio of the plurality of exhaust ports 96 at the portion 90 degrees away from the valve side exhaust port 150 and the main exhaust port 160 is the highest.

  FIG. 2 is a perspective view showing the overall appearance of the holding unit 7. The holding part 7 includes a base ring 71, a connecting part 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 whole holding part 7 is made of quartz.

  The base ring 71 is an arc-shaped quartz member that is partially missing from the annular shape. This missing portion is provided to prevent interference between a transfer arm 11 and a base ring 71 of the transfer mechanism 10 described later. The base ring 71 is supported on the wall surface of the chamber 6 by being placed on the bottom surface of the recess 62 (see FIG. 1). On the upper surface of the base ring 71, a plurality of connecting portions 72 (four in this embodiment) are erected along the annular circumferential direction. 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. 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 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.

  A guide ring 76 is installed on the peripheral edge 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, when the diameter of the semiconductor wafer W is φ300 mm, the inner diameter of the guide ring 76 is φ320 mm. The inner periphery of the guide ring 76 has a tapered surface that widens upward from the holding plate 75. The guide ring 76 is formed 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 with 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 inside the guide ring 76 on the upper surface of the holding plate 75 is a flat holding surface 75 a that holds the semiconductor wafer W. A plurality of substrate support pins 77 are provided upright on the holding surface 75 a of the holding plate 75. In the present embodiment, a total of twelve substrate support pins 77 are erected every 30 ° along a circumference concentric with the outer circumference of the holding surface 75a (the inner circumference of the guide ring 76). The diameter of the circle on which the 12 substrate support pins 77 are arranged (the distance between the substrate support pins 77 facing each other) is smaller than the diameter of the semiconductor wafer W. If the diameter of the semiconductor wafer W is 300 mm, then 270 mm to 280 mm (this embodiment) In the form, 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 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. When the base ring 71 of the holding unit 7 is supported on the wall surface of the chamber 6, the holding unit 7 is attached to the chamber 6. In a state where the holding unit 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 matches 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 unit 7 attached to the chamber 6. At this time, the semiconductor wafer W is supported by twelve substrate support pins 77 erected on the holding plate 75 and held by the susceptor 74. More precisely, the upper ends of the twelve substrate support pins 77 are in contact with the lower surface of the semiconductor wafer W to support the semiconductor wafer W. Since the height of the 12 substrate support pins 77 (the distance from the upper end of the substrate support pin 77 to the holding surface 75a of the holding plate 75) is uniform, the semiconductor wafer W is placed in a horizontal posture 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 at a predetermined interval from the holding surface 75 a of the holding plate 75. The thickness of the guide ring 76 is greater than the height of the substrate support pins 77. Accordingly, the horizontal displacement of the semiconductor wafer W supported by the plurality of substrate support pins 77 is prevented by the guide ring 76.

  As shown in FIGS. 2 and 3, the holding plate 75 of the susceptor 74 has an opening 78 penetrating vertically. The opening 78 is provided for the radiation thermometer 20 to receive radiated light (infrared light) emitted from the lower surface of the semiconductor wafer W. That is, the radiation thermometer 20 receives light emitted from the lower surface of the semiconductor wafer W through the transparent window 21 attached to the opening 78 and the through-hole 61a of the chamber side portion 61, and determines the temperature of the semiconductor wafer W. taking measurement. Further, 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 to be described later penetrate for the delivery of the semiconductor wafer W.

  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 arm 11 has an arc shape that follows the generally 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 can be rotated by a horizontal movement mechanism 13. The horizontal movement mechanism 13 includes a transfer operation position (a position indicated by a solid line in FIG. 5) for transferring the pair of transfer arms 11 to the holding unit 7 and the semiconductor wafer W held by the holding unit 7. It is moved horizontally between the retracted positions (two-dot chain line positions in FIG. 5) that do not overlap in plan view. As the horizontal movement mechanism 13, each transfer arm 11 may be rotated by an individual motor, or a pair of transfer arms 11 may be interlocked by a single motor using a link mechanism. It may be moved.

  The pair of transfer arms 11 are moved up and down together with the horizontal moving mechanism 13 by the lifting 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 pins 12 are extracted from the through holes 79, and the horizontal movement mechanism 13 moves the pair of transfer arms 11 so as to open each of them. 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 unit 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. Note that an exhaust mechanism (not shown) is also provided in the vicinity of the portion where the drive unit (the horizontal movement mechanism 13 and the lifting mechanism 14) of the transfer mechanism 10 is provided, and the atmosphere around the drive unit of the transfer mechanism 10 Is discharged to the outside of the chamber 6.

  Returning to FIG. 1, the flash heating unit 5 provided above the chamber 6 includes a light source including a plurality of (30 in the present embodiment) xenon flash lamps FL inside the housing 51, and an upper part of the light source. And a reflector 52 provided so as to cover. A lamp light emission window 53 is mounted on the bottom of the casing 51 of the flash heating unit 5. The lamp light emission window 53 constituting the floor of the flash heating unit 5 is a plate-like quartz window made of quartz. By installing the flash heating unit 5 above the chamber 6, the lamp light emission 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 emission 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 of each of the flash lamps FL is along the main surface of the semiconductor wafer W held by the holding unit 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 lamps FL is also a horizontal plane. The region where the plurality of flash lamps FL are arranged is larger than the planar size of the semiconductor wafer W.

  The xenon flash lamp FL includes a cylindrical glass tube (discharge tube) in which xenon gas is sealed and a positive electrode and a negative electrode connected to a capacitor at both ends thereof, and an outer peripheral surface of the glass tube. And an attached trigger electrode. Since xenon gas is an electrical insulator, electricity does not flow into the glass tube under normal conditions even if electric charges are accumulated in the capacitor. However, when the insulation is broken by applying a high voltage to the trigger electrode, the electricity stored in the capacitor flows instantaneously in the glass tube, and light is emitted by excitation of atoms or molecules of xenon at that time. In such a xenon flash lamp FL, the electrostatic energy previously stored in the capacitor is converted into an extremely short light pulse of 0.1 to 100 milliseconds, so that the continuous lighting such as the halogen lamp HL is possible. It has the characteristic that it can irradiate extremely strong light compared with a light source. That is, the flash lamp FL is a pulse light emitting lamp that emits light instantaneously 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 source that supplies power to the flash lamp FL.

  In addition, 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 formed of an aluminum alloy plate, and the surface (the surface facing the flash lamp FL) is roughened by blasting.

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

  FIG. 7 is a plan view showing the arrangement of the plurality of halogen lamps HL. Forty halogen lamps HL are arranged in two upper and lower stages. Twenty halogen lamps HL are arranged on the upper stage close to the holding unit 7, and twenty halogen lamps HL are arranged on the lower stage farther from the holding unit 7 than 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 unit 7 (that is, along the horizontal direction). Yes. Therefore, the plane formed by the arrangement of the halogen lamps HL in both the upper stage and the lower stage is a horizontal plane.

  Further, as shown in FIG. 7, the arrangement density of the halogen lamps HL in the region facing the peripheral 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 stage and the lower stage. Yes. That is, in both the upper and lower stages, the arrangement pitch of the halogen lamps HL is shorter in the peripheral part than in the central part of the lamp array. For this reason, it is possible to irradiate a larger amount of light to the peripheral portion of the semiconductor wafer W where the temperature is likely to decrease during heating by light irradiation from the halogen heating unit 4.

  Further, the lamp group composed of the upper halogen lamp HL and the lamp group composed of the lower halogen lamp HL are arranged so as to intersect in a lattice 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. Yes.

  The halogen lamp HL is a filament-type light source that emits light by making the filament incandescent by energizing the filament disposed inside the cylindrical glass tube. Inside the glass tube, a gas obtained by introducing a trace amount of a halogen element (iodine, bromine, etc.) into an inert gas such as nitrogen or argon is enclosed. By introducing a halogen element, it is possible to set the filament temperature to a high temperature while suppressing breakage of the filament. Therefore, the halogen lamp HL has a characteristic that it has a longer life than a normal incandescent bulb and can continuously radiate strong light. That is, the halogen lamp HL is a continuous lighting lamp that emits light continuously for at least one second. 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 in the housing 41 of the halogen heating unit 4 below the two-stage halogen lamp HL (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 includes a CPU that is a circuit that performs various arithmetic processes, a ROM that is a read-only memory that stores basic programs, a RAM that is a readable and writable memory that stores various information, control software, data, and the like. It has a magnetic disk to store. The processing in the heat treatment apparatus 1 proceeds as 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 in the halogen heating unit 4, the flash heating unit 5, and the chamber 6 due to thermal energy generated from the halogen lamp HL and the flash lamp FL during the heat treatment of the semiconductor wafer W. Therefore, various cooling structures are provided. For example, the wall of the chamber 6 is provided with a water-cooled tube (not shown). Further, the halogen heating unit 4 and the flash heating unit 5 have an air cooling structure in which a gas flow is formed inside to exhaust heat. 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 the upper chamber window 63.

  Next, a processing procedure for the semiconductor wafer W in the heat treatment apparatus 1 will be described. The semiconductor wafer W to be processed here is a semiconductor substrate to which impurities (ions) are added by an ion implantation method. The activation of the impurities is performed by flash light irradiation heat treatment (annealing) by the heat treatment apparatus 1. The processing procedure of the heat treatment apparatus 1 described below proceeds by the control unit 3 controlling each operation mechanism of the heat treatment apparatus 1.

  First, the supply valve 84 for supplying air is opened, and the first exhaust valve 152 and the second exhaust valve 162 for exhaust are opened, and supply / exhaust into the chamber 6 is started. When the supply valve 84 is opened, nitrogen gas is supplied from the gas supply hole 81 to the heat treatment space 65. When the first exhaust valve 152 and the second exhaust valve 162 are opened, the gas in the chamber 6 is exhausted from the plurality of exhaust ports 96 of the exhaust ring 90. Thereby, 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. The gas sucked from the plurality of exhaust ports 96 flows through the annular buffer portion 95 and flows into the gate valve side exhaust port 150 and / or the main exhaust port 160, and the first exhaust pipe 151 and / or the second exhaust. It is discharged to the outside of the heat treatment apparatus 1 through the pipe 161. The exhaust of the gas in the chamber 6 by the exhaust ring 90 will be further described later.

  Subsequently, the gate valve 185 is opened to open the transfer opening 66, and the semiconductor wafer W after ion implantation is transferred into the heat treatment space 65 in the chamber 6 through the transfer opening 66 by a transfer robot outside the apparatus. At this time, there is a possibility that the atmosphere outside the apparatus is involved with the carry-in of the semiconductor wafer W. However, since the nitrogen gas is continuously supplied to the chamber 6, the nitrogen gas flows out from the transfer opening 66, and so on. It is possible to suppress the entrainment of a simple external atmosphere to a minimum.

  The semiconductor wafer W carried in by the carrying robot advances to a position directly above the holding unit 7 and stops. Then, when the pair of transfer arms 11 of the transfer mechanism 10 moves horizontally from the retracted position to the transfer operation position and rises, the lift pin 12 protrudes from the upper surface of the holding plate 75 of the susceptor 74 through the through hole 79. The semiconductor wafer W is received. At this time, the lift pins 12 ascend above the upper ends of the substrate support pins 77.

  After the semiconductor wafer W is placed on the lift pins 12, the transfer robot leaves the heat treatment space 65 and the transfer opening 66 is closed by the gate valve 185. When the pair of transfer arms 11 are lowered, the semiconductor wafer W is transferred from the transfer mechanism 10 to the susceptor 74 of the holding unit 7 and held from below in a horizontal posture. 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. The semiconductor wafer W is held by the holding unit 7 with the surface on which the pattern is formed and the impurities are implanted as the upper surface. A predetermined gap 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 75 a of the holding plate 75. The pair of transfer arms 11 lowered to below the susceptor 74 is retracted to the retracted position, that is, inside the recess 62 by the horizontal movement mechanism 13.

  After the semiconductor wafer W is held from below in a horizontal posture by the susceptor 74 of the holding unit 7 formed of quartz, the 40 halogen lamps HL of the halogen heating unit 4 are turned on all at once and preheated (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 is irradiated onto the lower surface of the semiconductor wafer W. By receiving light from the halogen lamp HL, the semiconductor wafer W is preheated and the temperature rises. In addition, since the transfer arm 11 of the transfer mechanism 10 is retracted to the inside of the recess 62, there is no obstacle to heating by the halogen lamp HL.

  When preheating is performed by the halogen lamp HL, the temperature of the semiconductor wafer W is measured by the radiation thermometer 20. That is, the radiation thermometer 20 receives the infrared light radiated from the lower surface of the semiconductor wafer W held by the susceptor 74 through the opening 78 through the transparent window 21, and measures the temperature of the wafer being heated. The measured temperature of the semiconductor wafer W is transmitted to the control unit 3. The controller 3 controls the output of the halogen lamp HL while monitoring whether or not the temperature of the semiconductor wafer W that is heated 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 based on the measurement value by the radiation thermometer 20 so that the temperature of the semiconductor wafer W becomes the preheating temperature T1. The preheating temperature T1 is set to about 200 ° C. to 800 ° C., preferably about 350 ° C. to 600 ° C. (in this embodiment, 600 ° C.) at which impurities added to the semiconductor wafer W are not likely to diffuse due to heat. .

  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, so that the temperature of the semiconductor wafer W is almost preliminarily set. The heating temperature is maintained at T1.

  By performing such preheating by the halogen lamp HL, the entire semiconductor wafer W is uniformly heated to the preheating temperature T1. In the preliminary heating stage with the halogen lamp HL, the temperature of the peripheral edge of the semiconductor wafer W where heat dissipation is more likely to occur tends to be lower than that in the central area, but the arrangement density of the halogen lamps HL in the halogen heating section 4 is The region facing the peripheral portion is higher than the region facing the central portion of the substrate W. For this reason, the light quantity irradiated to the peripheral part of the semiconductor wafer W which tends to generate heat increases, and the in-plane temperature distribution of the semiconductor wafer W in the preheating stage can be made uniform.

  When a predetermined time elapses after the temperature of the semiconductor wafer W reaches the preheating temperature T1, the flash lamp FL of the flash heating unit 5 is irradiated with flash light on the surface of the semiconductor wafer W held by the susceptor 74. At this time, a part of the flash light emitted 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. Flash heating of the semiconductor wafer W is performed by irradiation.

  Since the flash heating is performed by irradiation with flash light (flash light) from the flash lamp FL, the surface temperature of the semiconductor wafer W can be increased in a short time. That is, the flash light irradiated from the flash lamp FL is converted into a light pulse in which the electrostatic energy stored in the capacitor in advance is extremely short, and the irradiation time is extremely short, about 0.1 milliseconds to 100 milliseconds. It is a strong flash. Then, the surface temperature of the semiconductor wafer W that is flash-heated by flash light irradiation from the flash lamp FL instantaneously rises to a processing temperature T2 of 1000 ° C. or more, and the impurities injected into the semiconductor wafer W are activated. Later, the surface temperature drops rapidly. As described above, in the heat treatment apparatus 1, the surface temperature of the semiconductor wafer W can be raised and lowered in a very short time, so that the impurities are activated while suppressing diffusion of the impurities injected into the semiconductor wafer W due to heat. Can do. Since the time required for the activation of impurities is extremely short compared to the time required for the thermal diffusion, the activation is possible even in a short time in which diffusion of about 0.1 millisecond to 100 millisecond does not occur. Complete.

  After the end of the flash heat treatment, the halogen lamp HL is turned off after a predetermined time has elapsed. Thereby, the temperature of the semiconductor wafer W is rapidly lowered from the preheating temperature T1. The temperature of the semiconductor wafer W during the temperature drop is measured by the radiation thermometer 20, and the measurement result is transmitted to the control unit 3. The controller 3 monitors whether or not the temperature of the semiconductor wafer W has dropped to a predetermined temperature from the measurement result of the radiation thermometer 20. Then, after the temperature of the semiconductor wafer W is lowered to a predetermined temperature or lower, the pair of transfer arms 11 of the transfer mechanism 10 is again moved horizontally from the retracted position to the transfer operation position and lifted, whereby the lift pins 12 are moved to the susceptor. The semiconductor wafer W protruding from the upper surface of 74 and subjected to the heat treatment is received from the susceptor 74. Subsequently, the transfer opening 66 closed by the gate valve 185 is opened, and the semiconductor wafer W placed on the lift pins 12 is unloaded by the transfer robot outside the apparatus, and the heat treatment of the semiconductor wafer W in the heat treatment apparatus 1 is performed. Is completed.

  By the way, since the flash light having extremely high energy is instantaneously irradiated onto the surface of the semiconductor wafer W at the time of flash heating, the surface temperature of the semiconductor wafer W rapidly rises instantaneously. As a result, the surface of the semiconductor wafer W undergoes rapid thermal expansion and is deformed, causing sliding between the lower surface of the semiconductor wafer W and the susceptor 74 and turbulence in the air flow, which may generate particles in the chamber 6. . Since such particles cause contamination of the semiconductor wafer W, by increasing the flow rate of nitrogen gas supplied from the gas supply hole 81 into the chamber 6 to, for example, 100 liters / minute, the generated particles can be efficiently removed from the chamber. It is effective to discharge from 6. Note that the timing for increasing the flow rate of the nitrogen gas is not particularly limited, and can be set at an appropriate time (for example, immediately before or after the flash light irradiation). However, when the flow rate of the nitrogen gas supplied into the chamber 6 is increased, the flow of the nitrogen gas in the chamber 6 becomes non-uniform, and the in-plane uniformity of the temperature distribution of the semiconductor wafer W during the heat treatment may be reduced. .

  For this reason, in the present embodiment, the processing gas in the chamber 6 is uniformly exhausted by the exhaust ring 90 provided with a plurality of exhaust ports 96. FIG. 9 is a diagram schematically showing the flow of exhaust from the chamber 6 by the exhaust ring 90. FIG. 9 is a view of the inside of the chamber 6 as viewed from above.

  The negative pressure generated in the exhaust unit 190 directly acts on the gate valve side exhaust port 150 and the main exhaust port 160. Therefore, a stronger negative pressure acts on the exhaust ports 96 closer to the gate valve side exhaust port 150 and the main exhaust port 160 among the plurality of exhaust ports 96 provided in the exhaust ring 90. Gas is exhausted from the exhaust port 96 where a strong negative pressure acts at a larger flow rate than the exhaust port 96 where a weak negative pressure acts. The magnitude of the negative pressure applied to each of the gate valve side exhaust port 150 and the main exhaust port 160 can be adjusted by the first conductance adjustment valve 153 and the second conductance adjustment valve 163. A negative pressure equal to the valve side exhaust port 150 and the main exhaust port 160 is applied.

  In the present embodiment, a plurality of exhaust ports 96 are provided so that the aperture ratio increases as the distance from the gate valve side exhaust port 150 and the main exhaust port 160 along the circumferential direction of the exhaust ring 90 increases. More specifically, the opening ratio of the plurality of exhaust ports 96 is highest at a portion that is 90 ° apart from the gate valve side exhaust port 150 and the main exhaust port 160 along the circumferential direction of the exhaust ring 90. Accordingly, a negative pressure having substantially the same strength acts on all of the plurality of exhaust ports 96 provided in the exhaust ring 90. As a result, as shown in FIG. 9, the gas in the chamber 6 is exhausted at a uniform flow rate over the entire circumference of the annular exhaust ring 90 (that is, over the entire outer periphery of the semiconductor wafer W). Even if the flow rate of the processing gas supplied to the chamber is increased, the processing gas can be made to flow uniformly in the chamber 6. Thereby, the in-plane uniformity of the temperature distribution of the semiconductor wafer W during the heat treatment can also be maintained.

  While the embodiments of the present invention have been described above, the present invention can be modified in various ways other than those described above without departing from the spirit of the present invention. For example, in the embodiment described above, the exhaust ring 90 is provided with the round hole exhaust port 96, but the shape of the exhaust port 96 is not limited to the round hole, and various forms can be adopted. FIG. 10 is a perspective view showing an exhaust ring 90 provided with an exhaust port of another shape. In the example shown in FIG. 10, a plurality of elongated holes 196 are formed in the exhaust ring 90. Also in the example shown in FIG. 10, the opening ratio of the plurality of exhaust ports 196 increases as the distance from the gate valve side exhaust port 150 and the main exhaust port 160 along the circumferential direction of the exhaust ring 90 increases. Except for the shape of the exhaust port 196, the remaining structure of the exhaust ring 90 shown in FIG. 10 is the same as that of the above-described embodiment (FIG. 8). Even in the exhaust ring 90 as shown in FIG. 10, the gas in the chamber 6 can be exhausted at a uniform flow rate over the entire outer periphery of the semiconductor wafer W, and the same effect as in the above embodiment can be obtained. . Furthermore, the shape of the exhaust port provided in the exhaust ring 90 may be a hole or notch having another shape.

  In the above embodiment, the negative pressure equal to the gate valve side exhaust port 150 and the main exhaust port 160 is applied. However, the first conductance adjustment valve 153 and the second conductance adjustment valve 163 provide the gate valve side exhaust port 150. A negative pressure with a different magnitude may be applied to the main exhaust port 160. For example, when the transfer opening 66 is opened by the gate valve 185 and the semiconductor wafer W is carried into and out of the chamber 6 via the transfer opening 66, particles easily flow from the transfer opening 66. Therefore, the negative pressure acting on the gate valve side exhaust port 150 is made larger than the negative pressure acting on the main exhaust port 160 by the first conductance adjustment valve 153 and the second conductance adjustment valve 163. As a result, the exhaust flow rate from the gate valve side exhaust port 150 becomes larger than the exhaust flow rate from the main exhaust port 160, and particles flowing in from the transfer opening 66 can be effectively discharged.

  In the above embodiment, the chamber 6 is provided with the two exhaust ports of the gate valve side exhaust port 150 and the main exhaust port 160. However, the present invention is not limited to this, and the exhaust port provided in the chamber 6 is not limited thereto. The number may be one, or may be three or more. Regardless of the number of exhaust ports provided in the chamber 6, a plurality of exhaust ports 96 are provided so that the aperture ratio increases as the distance from the exhaust port along the circumferential direction of the exhaust ring 90 increases. A negative pressure of almost the same strength can be applied to all 96. As a result, the processing gas can flow uniformly in the chamber 6.

  Further, the technique according to the present invention is suitably applied not only when a processing gas is supplied into the chamber 6 at a large flow rate but also when a processing gas is supplied into the chamber 6 at a relatively small flow rate. Can do. For example, if the technique according to the present invention is applied when a reactive gas such as ammonia or forming gas is supplied into the chamber 6 at a relatively small flow rate (for example, 5 liters / minute), the reactivity in the chamber 6 is increased. The gas can be made to flow uniformly, and the reaction uniformity within the surface of the semiconductor wafer W can be improved. Furthermore, the technology according to the present invention can also be applied when processing the semiconductor wafer W in a reduced pressure atmosphere (for example, 5 kPa) in the chamber 6, so that the processing gas existing in the chamber 6 is uniformly distributed. It can flow in the plane of the semiconductor wafer W.

  In the above embodiment, the flash heating unit 5 is provided with 30 flash lamps FL. However, the present invention is not limited to this, and the number of flash lamps FL can be any number. . The flash lamp FL is not limited to a 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 may be an arbitrary number.

  The substrate to be processed by the heat treatment apparatus according to the present invention is not limited to a semiconductor wafer, and may be a glass substrate or a solar cell substrate used for a flat panel display such as a liquid crystal display device. Further, the heat treatment apparatus according to the present invention may perform heat treatment of the high dielectric constant gate insulating film (High-k film), bonding of metal and silicon, or crystallization of polysilicon.

  Further, the technology according to the present invention is not limited to a flash lamp annealing apparatus, and a predetermined processing gas is supplied into a chamber of a single wafer type lamp annealing apparatus or a CVD apparatus using a halogen lamp, The present invention can be suitably applied to a device that exhausts the gas in the chamber.

DESCRIPTION OF SYMBOLS 1 Heat processing apparatus 3 Control part 4 Halogen heating part 5 Flash heating part 6 Chamber 7 Holding part 10 Transfer mechanism 63 Upper chamber window 64 Lower chamber window 65 Heat treatment space 74 Susceptor 81 Gas supply hole 85 Process gas supply source 90 Exhaust ring 95 Buffer part 150 Gate valve side exhaust port 151 First exhaust pipe 152 First exhaust valve 153 First conductance adjustment valve 160 Main exhaust port 161 Second exhaust pipe 162 Second second exhaust valve 163 Second conductance adjustment valve 190 Exhaust parts 96, 196 Exhaust port FL Flash lamp HL Halogen lamp W Semiconductor wafer

Claims (4)

A heat treatment apparatus for heating a substrate by irradiating the substrate with light,
A chamber having a substantially cylindrical side wall;
A holding unit for holding the substrate in the chamber;
A light irradiation unit that irradiates light to the substrate held by the holding unit;
A gas supply unit for supplying a processing gas into the chamber;
A first exhaust port that is provided on the side of the furnace port that carries the substrate in and out of the side wall of the side wall, and discharges the gas in the chamber;
A second exhaust port that is provided on the opposite side of the side wall from the first exhaust port and exhausts the gas in the chamber;
An annular exhaust ring that is attached to the side wall so as to cover the first exhaust port and the second exhaust port, and guides the gas in the chamber to the first exhaust port and the second exhaust port;
With
The exhaust ring is
A plurality of exhaust ports for sucking the gas in the chamber;
The plurality of exhaust ports are connected in communication with the first exhaust port and the second exhaust port, and the gas sucked from the plurality of exhaust ports is disposed along the circumferential direction of the exhaust ring and the first exhaust port and the second exhaust port. 2 an annular buffer that flows through the exhaust port;
With
The opening ratio of the plurality of exhaust ports is higher as the distance from the first exhaust port and the second exhaust port along the circumferential direction of the exhaust ring increases. The heat treatment apparatus according to claim 1, wherein
The opening ratio of the plurality of exhaust ports is the highest in a portion separated by 90 ° from the first exhaust port and the second exhaust port along the circumferential direction of the exhaust ring. In the heat treatment apparatus according to claim 1 or 2,
A first exhaust pipe connected to the first exhaust port;
A second exhaust pipe connected to the second exhaust port;
A first conductance adjustment valve provided in the first exhaust pipe for adjusting a pressure loss of the first exhaust pipe;
A second conductance adjustment valve provided in the second exhaust pipe for adjusting a pressure loss of the second exhaust pipe;
Further comprising
When the substrate is carried into and out of the chamber through the furnace port, the exhaust flow rate from the first exhaust port is controlled from the second exhaust port by the first conductance adjustment valve and the second conductance adjustment valve. The heat treatment apparatus is characterized in that the flow rate is higher than the exhaust flow rate. A heat treatment apparatus for heating a substrate by irradiating the substrate with light,
A chamber having a substantially cylindrical side wall;
A holding unit for holding the substrate in the chamber;
A light irradiation unit that irradiates light to the substrate held by the holding unit;
A gas supply unit for supplying a processing gas into the chamber;
An exhaust port that is provided in a part of the side wall and exhausts the gas in the chamber;
An annular exhaust ring that is attached to the side wall so as to cover the exhaust port and guides the gas in the chamber to the exhaust port;
With
The exhaust ring is
A plurality of exhaust ports for sucking the gas in the chamber;
An annular buffer part that connects the plurality of exhaust ports and the exhaust port in communication, and flows gas sucked from the plurality of exhaust ports to the exhaust port along the circumferential direction of the exhaust ring;
With
The opening ratio of the plurality of exhaust ports increases as the distance from the exhaust port along the circumferential direction of the exhaust ring increases.

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