JP2023131254A - Heat processing device - Google Patents

Abstract

To provide a heat processing device that can prevent the temperature of a light emitting element from rising and efficiently heat a substrate.SOLUTION: A heat processing device 1 heats a semiconductor wafer W by irradiating the semiconductor wafer W with light. The heat processing device 1 includes a chamber 6 that accommodates the semiconductor wafer W, a plurality of LED lamps 45 that emit light, and a plurality of optical fibers 46 that are respectively connected to the plurality of LED lamps 45. Furthermore, in the heat processing device 1, one end of each of the plurality of optical fibers 46 is connected to the LED lamp 45, and the other end of the plurality of optical fibers 46 is arranged in a plane to form a light emitting surface 47.SELECTED DRAWING: Figure 1

Description

The present invention relates to a heat treatment apparatus that heats a thin precision electronic substrate (hereinafter simply referred to as a "substrate") such as a semiconductor wafer by irradiating the substrate with light.

In the manufacturing process of semiconductor devices, flash lamp annealing (FLA), which heats semiconductor wafers in an extremely short period of time, is attracting attention. Flash lamp annealing is a process in which only the surface of a semiconductor wafer is extremely polished by irradiating the surface of the semiconductor wafer with flash light using a xenon flash lamp (hereinafter simply referred to as "flash lamp"). This is a heat treatment technology that raises the temperature in a short period of time (several milliseconds or less).

The radiation spectral distribution of a xenon flash lamp ranges from the ultraviolet region to the near-infrared region, which has a shorter wavelength than that of conventional halogen lamps and roughly matches the fundamental absorption band of silicon semiconductor wafers. Therefore, when a semiconductor wafer is irradiated with flash light from a xenon flash lamp, the amount of transmitted light is small and it is possible to rapidly raise the temperature of the semiconductor wafer. It has also been found that by irradiating flash light for an extremely short period of several milliseconds or less, it is possible to selectively raise the temperature only in the vicinity of the surface of the semiconductor wafer.

Such flash lamp annealing is used for processes that require very short heating times, such as typically for activating impurities implanted into semiconductor wafers. By irradiating the surface of a semiconductor wafer into which impurities have been implanted using the ion implantation method with flash light from a flash lamp, the surface of the semiconductor wafer can be heated to the activation temperature for a very short period of time, allowing the impurities to be deeply diffused. Only impurity activation can be performed without activation.

As an apparatus for performing such flash lamp annealing, a heat treatment apparatus is typically used in which a flash lamp is provided above a chamber that accommodates a semiconductor wafer, and a halogen lamp is provided below.

Halogen lamps mainly emit infrared light with relatively long wavelengths. Regarding the spectral absorption rate of a silicon semiconductor wafer, the absorption rate of infrared light with a long wavelength larger than 1 μm is low in a low temperature range of 500° C. or lower. In other words, semiconductor wafers at temperatures below 500°C do not absorb much infrared light emitted from halogen lamps, so if preheating is performed using halogen lamps, inefficient heating will occur in the initial stage of preheating. . Therefore, a means other than a halogen lamp has been required as a preheating means.

Further, as described in Patent Document 1, in a burn-in process in which a completed semiconductor wafer is further heated, an LED is employed as a heating means for the semiconductor wafer. In the device described in Patent Document 1, LEDs are arranged at high density in order to bring the semiconductor wafer up to the required temperature in a short time.

JP2020-9927A

However, when LEDs are arranged in a high density as in the device described in Patent Document 1, the heat of the LEDs themselves due to light emission influences each other, so there is a possibility that the temperature of the LEDs themselves increases.

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 that can prevent a rise in temperature of a light emitting element and efficiently heat a substrate.

In order to solve the above problem, the invention of claim 1 provides a heat treatment apparatus that heats a substrate by irradiating the substrate with light, the apparatus comprising: a chamber that accommodates the substrate; and a plurality of light emitting elements that emit light. , a plurality of optical fibers individually connected to each of the plurality of light emitting elements, one end of each of the plurality of optical fibers is connected to the light emitting element, and the other end of the plurality of optical fibers is connected to a surface. It is characterized by being arranged in a shape to form a light emitting surface.

Further, the invention according to claim 2 is characterized in that in the heat treatment apparatus according to the invention according to claim 1, the light emitting surface is formed at a position closer to the substrate than the plurality of light emitting elements.

Moreover, the invention according to claim 3 is characterized in that, in the heat treatment apparatus according to the invention according to claim 2, the light emitting surface is disposed below the substrate.

Moreover, the invention according to claim 4 is characterized in that in the heat treatment apparatus according to the invention according to claim 3, the light emitting surface is also arranged above the substrate.

Further, the invention of claim 5 is the heat treatment apparatus according to any one of claims 1 to 4, in which light is condensed between the one end of each of the plurality of optical fibers and the light emitting element. It is characterized by the presence of a condensing lens.

Moreover, the invention according to claim 6 is characterized in that in the heat treatment apparatus according to any one of claims 1 to 5, the plurality of light emitting elements are a plurality of light emitting diodes.

Further, the invention according to claim 7 is characterized in that, in the heat treatment apparatus according to the invention according to claim 6, the plurality of light emitting diodes are arranged on a mounting plate, and further comprising a cooling mechanism that cools the mounting plate. do.

Further, the invention according to claim 8 is characterized in that the heat treatment apparatus according to any one of claims 1 to 7 further includes a flash lamp that heats the substrate by irradiating the substrate with flash light. .

Further, the invention of claim 9 is the heat treatment apparatus according to the invention of claim 8, further comprising a filter that cuts light of a predetermined wavelength from the light emitted from the flash lamp between the light emitting surface and the substrate. It is characterized by

According to the inventions of claims 1, 2, and 6, since a plurality of optical fibers are individually connected to each of a plurality of light emitting elements, excessive temperature rise of the light emitting elements can be prevented. Attenuation of light can be suppressed. Therefore, the substrate can be heated efficiently.

Further, according to the third and fourth aspects of the invention, since the light emitting surface is disposed below the substrate, preheating of the substrate is efficiently performed.

Further, according to the invention as set forth in claim 5, since a condensing lens for condensing light is interposed between one end of each of the plurality of optical fibers and the light emitting element, light from the light emitting element can be collected more efficiently. is emitted to the substrate. Thereby, the substrate can be heated even more efficiently.

According to the invention of claim 7, cooling of the light emitting element is facilitated since a cooling mechanism for cooling the mounting plate is further provided. Thereby, excessive temperature rise of the light emitting element can be prevented.

According to the eighth aspect of the present invention, since a flash lamp for heating the substrate is further provided, the temperature of the substrate can be rapidly raised.

According to the invention of claim 9, since the filter that cuts light of a predetermined wavelength from the light emitted from the flash lamp is provided between the light emitting surface and the substrate, the flash light from the flash lamp is emitted from the light emitting surface. It is prevented from reaching the element. Therefore, damage to the light emitting element can be prevented.

1 is a longitudinal cross-sectional view showing the configuration of a heat treatment apparatus according to the present invention. It is a perspective view showing the whole appearance of a holding part. FIG. 3 is a plan view of a susceptor. It is a sectional view of a susceptor. It is a top view of a transfer mechanism. It is a side view of a transfer mechanism. FIG. 3 is a plan view showing a plurality of LED lamps arranged on a disc-shaped mounting plate. It is a figure explaining the cooling mechanism inside a mounting plate. FIG. 2 is an enlarged view showing a connecting portion between an LED lamp and an optical fiber in FIG. 1. FIG. FIG. 2 is an enlarged view showing a connecting portion between an optical fiber and a light emitting surface. FIG. 3 is a plan view of a light emitting surface. FIG. 2 is a cross-sectional view schematically showing the configuration of a heat treatment apparatus in a second embodiment. FIG. 7 is a cross-sectional view schematically showing the configuration of a heat treatment apparatus in a third embodiment. FIG. 7 is an enlarged view showing a connecting portion between an LED lamp and an optical fiber in a heat treatment apparatus according to a fourth embodiment. FIG. 2 is a cross-sectional view schematically showing the configuration of a heat treatment apparatus in a modification of the first embodiment. FIG. 16 is a plan view schematically showing a plane of a side part of the chamber in FIG. 15;

Embodiments will be described below with reference to the accompanying drawings. In the following embodiments, detailed features and the like are shown for technical explanation, but these are merely examples, and not all of them are necessarily essential features for the embodiments to be implemented.

Note that the drawings are shown schematically, and for convenience of explanation, structures are omitted or simplified as appropriate in the drawings. Further, the mutual relationship between the sizes and positions of the structures shown in different drawings is not necessarily described accurately and may be changed as appropriate. Further, even in drawings such as plan views that are not cross-sectional views, hatching may be added to facilitate understanding of the content of the embodiments.

In addition, in the following description, similar components are shown with the same reference numerals, and their names and functions are also the same. Therefore, detailed descriptions thereof may be omitted to avoid duplication.

In addition, in the description below, when a component is described as "comprising," "includes," or "has," unless otherwise specified, it is an exclusive term that excludes the presence of other components. It's not an expression.

In addition, in the description below, expressions indicating relative or absolute positional relationships, such as "in one direction", "along one direction", "parallel", "orthogonal", "centered", Unless otherwise specified, terms such as "concentric" or "coaxial" include cases in which the positional relationship is strictly indicated, and cases in which the angle or distance is displaced within a range that allows tolerance or the same degree of function to be obtained. .

In addition, in the explanations below, expressions that indicate equal states, such as "same", "equal", "uniform", or "homogeneous", do not mean strictly equal states, unless otherwise specified. This shall include cases in which there is a difference in tolerance or in the range in which the same level of function can be obtained.

In addition, in the descriptions below, specific positions or directions such as "top", "bottom", "left", "right", "side", "bottom", "front" or "back" are meant. However, these terms are used for convenience to make it easier to understand the content of the embodiments, and the positions and directions when actually implemented are different from each other. It is unrelated.

In addition, in the explanations below, when "the top surface of..." or "the bottom surface of..." is stated, in addition to the top surface itself or the bottom surface of the component in question, the top surface of the component in question Alternatively, it also includes a state in which other components are formed on the lower surface. That is, for example, when it is described as "B provided on the upper surface of A", this does not preclude the presence of another component "C" between A and B.

<First embodiment>
Hereinafter, a heat treatment apparatus according to this embodiment will be explained.

FIG. 1 is a longitudinal sectional view showing the configuration of a heat treatment apparatus 1 according to the present invention. The heat treatment apparatus 1 in 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. Note that in FIG. 1 and the subsequent figures, 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 that accommodates a semiconductor wafer W, a flash heating section 5 that includes a plurality of flash lamps FL, and an LED heating section 4 that includes a plurality of LED (Light Emitting Diode) lamps 45. . A flash heating section 5 is provided on the upper side of the chamber 6, and an LED heating section 4 is provided on the lower side. The heat treatment apparatus 1 also includes, inside the chamber 6, a holding part 7 that holds the semiconductor wafer W in a horizontal position, and a transfer mechanism 10 that transfers the semiconductor wafer W between the holding part 7 and the outside of the apparatus. Equipped with Further, the heat treatment apparatus 1 includes a control unit 3 that controls the operating mechanisms provided in the LED heating unit 4, flash heating unit 5, and chamber 6 to perform heat treatment on the semiconductor wafer W.

The chamber 6 is constructed by mounting quartz chamber windows on the upper and lower sides of a cylindrical chamber side part 61. The chamber side part 61 has a generally cylindrical shape with an open top and bottom, and the upper opening is fitted with an upper chamber window 63 and closed, and the lower opening is fitted with a lower chamber window 64 and closed. ing. The upper chamber window 63 configuring the ceiling of the chamber 6 is a disc-shaped member made of quartz, and functions as a quartz window that transmits the flash light emitted from the flash heating section 5 into the chamber 6 . Further, the lower chamber window 64 constituting the floor of the chamber 6 is also a disk-shaped member made of quartz, and functions as a quartz window that transmits light from the LED heating section 4 into the chamber 6.

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

By attaching the reflective rings 68 and 69 to the chamber side portion 61, a recess 62 is formed in 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 portion 61 where the reflective rings 68 and 69 are not attached, the lower end surface of the reflective ring 68, and the upper end surface of the reflective 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 part 7 that holds the semiconductor wafer W. The chamber side portion 61 and the reflection rings 68, 69 are made of a metal material (for example, stainless steel) with excellent strength and heat resistance.

Furthermore, a transfer opening (furnace opening) 66 is formed in the chamber side portion 61 to carry 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 conveyance 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 from the transfer opening 66 through the recess 62, 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, the chamber side portion 61 is provided with a through hole 61a. 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 61a is a cylindrical hole for guiding infrared light emitted from the lower surface of a semiconductor wafer W held by a 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 of the through hole 61a intersects with 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 barium fluoride material that transmits infrared light in a wavelength range 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.

Further, a gas supply hole 81 for supplying 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 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 via a buffer space 82 formed in an annular shape inside the side wall of the chamber 6 . Gas supply pipe 83 is connected to processing gas supply source 85 . Further, a valve 84 is inserted in the middle of the gas supply pipe 83. When the valve 84 is opened, 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 to expand within the buffer space 82 , which has a lower 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 of these can be used. In the embodiment, nitrogen gas).

On the other hand, a gas exhaust hole 86 is formed in the lower part of the inner wall of the chamber 6 to exhaust the gas in the heat treatment space 65. The gas exhaust hole 86 is formed at a lower position than the recess 62 and may be provided in the reflective ring 69. The gas exhaust hole 86 is connected to a gas exhaust pipe 88 via a buffer space 87 formed in an annular shape inside the side wall of the chamber 6 . Gas exhaust pipe 88 is connected to exhaust section 190. Further, a valve 89 is inserted in the middle 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 through the buffer space 87 to the gas exhaust pipe 88 . Note that 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. Furthermore, the processing gas supply source 85 and the exhaust section 190 may be mechanisms provided in the heat treatment apparatus 1, or may be utilities in a factory where the heat treatment apparatus 1 is installed.

FIG. 2 is a perspective view showing the overall appearance of the holding section 7. As shown in FIG. The holding section 7 includes a base ring 71, a connecting section 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 a quartz member having an arcuate shape with a portion missing from the annular shape. This missing portion is provided to prevent interference between the transfer arm 11 of the transfer mechanism 10 and the base ring 71, which will be described later. By being placed on the bottom of the recess 62, the base ring 71 is supported by the wall of the chamber 6 (see FIG. 1). A plurality of connecting portions 72 (four in this embodiment) are erected on the upper surface of the base ring 71 along the circumferential direction of the annular shape. The connecting 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 parts 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 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 at the upper peripheral edge 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 300 mm, the inner diameter of the guide ring 76 is 320 mm. The inner periphery of the guide ring 76 has a tapered surface that becomes wider upward from the holding plate 75. The guide ring 76 is made of quartz like 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 using a separately machined 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 planar holding surface 75a that holds the semiconductor wafer W. A plurality of substrate support pins 77 are provided upright on the holding surface 75a of the holding plate 75. In this embodiment, a total of 12 substrate support pins 77 are provided upright every 30° along a circumference concentric with the outer circumference of the holding surface 75a (inner circumference of the guide ring 76). The diameter of the circle in which the 12 substrate support pins 77 are arranged (the 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, it is φ270 mm to φ280 mm (in this implementation). The shape is φ270mm). 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 parts 72 erected on the base ring 71 and the peripheral edge 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 holding part 7 is attached to the chamber 6 by supporting the base ring 71 of the holding part 7 on the wall surface of the chamber 6 . When the holding portion 7 is attached to the chamber 6, the holding plate 75 of the susceptor 74 is in a horizontal position (a position in which the normal line coincides with the vertical direction). That is, the holding surface 75a of the holding plate 75 is a horizontal surface.

The semiconductor wafer W carried into the chamber 6 is placed and held in a horizontal position on the susceptor 74 of the holding section 7 mounted in 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 contact 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 held 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 at a predetermined distance from the holding surface 75a of the holding plate 75. The thickness of the guide ring 76 is greater than the height of the substrate support pin 77. Therefore, the guide ring 76 prevents the semiconductor wafer W supported by the plurality of substrate support pins 77 from shifting in the horizontal direction.

Further, as shown in FIGS. 2 and 3, an opening 78 is formed in the holding plate 75 of the susceptor 74 so as to pass through the holding plate 75 vertically. The opening 78 is provided so that the radiation thermometer 20 receives radiation light (infrared light) emitted from the lower surface of the semiconductor wafer W. That is, the radiation thermometer 20 receives the light emitted from the lower surface of the semiconductor wafer W through the transparent window 21 installed in the opening 78 and the through hole 61a of the chamber side part 61, and measures the temperature of the semiconductor wafer W. Measure. Furthermore, four through holes 79 are formed in the holding plate 75 of the susceptor 74, through which lift pins 12 of a transfer mechanism 10, which will be described later, pass through to transfer the semiconductor wafer W.

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 arcuate shape along the generally annular recess 62 . Two lift pins 12 are provided upright on each transfer arm 11. The transfer arm 11 and lift pin 12 are made of quartz. Each transfer arm 11 is rotatable by a horizontal movement mechanism 13. The horizontal movement mechanism 13 moves the pair of transfer arms 11 to a transfer operation position (solid line position in FIG. 5) in which the semiconductor wafer W is transferred to the holding part 7 and a semiconductor wafer W held by the holding part 7. It is horizontally moved between the retracted positions (positions indicated by two-dot chain lines in FIG. 5) where they do not overlap in plan view. The horizontal movement mechanism 13 may be one in which each transfer arm 11 is rotated by an individual motor, or one in which a pair of transfer arms 11 are rotated in conjunction with one motor using a link mechanism. It may be something that moves.

Further, the pair of transfer arms 11 are moved up and down together with the horizontal movement mechanism 13 by the lifting mechanism 14 . When the lifting mechanism 14 raises the pair of transfer arms 11 to the transfer operation position, a total of four lift pins 12 pass through the through holes 79 (see FIGS. 2 and 3) drilled in the susceptor 74, and the lift pins The upper end of 12 protrudes from the upper surface of susceptor 74. On the other hand, when the lifting mechanism 14 lowers the pair of transfer arms 11 at the transfer operation position and extracts the lift pin 12 from the through hole 79, and the horizontal movement mechanism 13 moves the pair of transfer arms 11 to open, each The transfer arm 11 moves to the retreat position. The retracted position of the pair of transfer arms 11 is directly above the base ring 71 of the holding section 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 near the parts where the drive parts (horizontal movement mechanism 13 and lifting mechanism 14) of the transfer mechanism 10 are provided, and the atmosphere around the drive parts of the transfer mechanism 10 is is configured so that the liquid 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 consisting of a plurality of xenon flash lamps FL (30 in this embodiment) inside a housing 51, and a light source above the light source. and a reflector 52 provided to cover the. Further, a lamp light emission window 53 is attached to the bottom of the casing 51 of the flash heating section 5. The lamp light emission window 53 constituting the floor of the flash heating section 5 is a plate-shaped 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.

The plurality of flash lamps FL are rod-shaped lamps each having an elongated cylindrical shape, and each of the flash lamps FL has its longitudinal direction along the main surface of the semiconductor wafer W held by the holding part 7 (that is, along the horizontal direction). They are arranged in a plane so that they are parallel to each other. Therefore, the plane formed by the arrangement of the flash lamps FL is also a horizontal plane. The area 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 consists of a cylindrical glass tube (discharge tube) in which xenon gas is sealed and an anode and a cathode connected to a condenser at both ends. and an attached trigger electrode. Since xenon gas is an electrical insulator, no electricity will flow inside the glass tube under normal conditions even if a charge is stored in the capacitor. However, when a high voltage is applied to the trigger electrode to break down the insulation, the electricity stored in the capacitor instantly flows into the glass tube, and the excitation of xenon atoms or molecules at that time causes light to be emitted. In such a xenon flash lamp FL, the electrostatic energy previously stored in the capacitor is converted into extremely short light pulses of 0.1 to 100 milliseconds, so it cannot be used as a continuous light source such as a halogen lamp. It has the characteristic of being able to irradiate extremely strong light compared to. That is, the flash lamp FL is a pulsed light emitting lamp that emits light instantaneously in an extremely short period of less than one second. Note that 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 them entirely. 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 side. The reflector 52 is formed of an aluminum alloy plate, and its surface (the surface facing the flash lamp FL) is roughened by blasting.

The LED heating unit 4 provided below the chamber 6 includes a plurality of LED lamps 45 as light emitting elements, a plurality of optical fibers 46, and a light emitting surface 47 inside a housing 41. Furthermore, the LED heating section 4 includes a filter 90 between the light emitting surface 47 and the semiconductor wafer W. The LED heating unit 4 heats the semiconductor wafer W by irradiating the heat treatment space 65 from below the chamber 6 through the lower chamber window 64 with light passing through the optical fiber 46 from the plurality of LED lamps 45 . The light emitting surface 47 has an area comparable to that of the semiconductor wafer W.

FIG. 7 is a plan view showing a plurality of LED lamps 45 arranged on a disc-shaped mounting plate 44. As shown in FIG. In the LED heating section 4, several thousand LED lamps 45 are arranged on a mounting plate 44. However, in FIG. 7, the number is simplified for convenience of illustration. While conventional halogen lamps are rod-shaped lamps, each LED lamp 45 is a square column-shaped point light source lamp. A disk-shaped mounting plate 44 on which a plurality of LED lamps 45 are arranged is installed parallel to the main surface of the semiconductor wafer W held by the holding part 7 (that is, along the horizontal direction). . Therefore, the plane formed by the arrangement of the plurality of LED lamps 45 is a horizontal plane.

FIG. 8 is a diagram illustrating a cooling mechanism inside the mounting plate 44. As shown in FIG. The mounting plate 44 includes a cooling mechanism therein. The cooling mechanism cools the plurality of LED lamps 45 arranged on the mounting plate 44. The mounting plate 44 has a disk shape and is made of metal or ceramic, for example. The mounting plate 44 is provided with a circulation passage 44a therein so that cooling water adjusted to a predetermined temperature (for example, 23° C.) circulates therein. The cooling water is circulated through the circulation channel 44a in the mounting plate 44 by the external pump 44b, thereby cooling the mounting plate 44 and the plurality of LED lamps 45 disposed thereon. Note that the mounting plate 44 may include a Peltier element as a cooling mechanism.

Further, as shown in FIG. 7, the plurality of LED lamps 45 are arranged concentrically. More specifically, the plurality of LED lamps 45 are arranged in a concentric circle coaxial with the central axis CX of the semiconductor wafer W held by the holding part 7. In each concentric circle, a plurality of LED lamps 45 are arranged at equal intervals. For example, in the example shown in FIG. 7, eight LED lamps 45 are evenly arranged at 45° intervals in the second concentric circle from the inside.

Further, it is preferable that adjacent LED lamps 45 are arranged at intervals of a distance L that is a predetermined value or more. The distance L is a distance that can suppress the temperature rise of the LED lamp 45 by eliminating the influence of heat from the adjacent LED lamp 45. When the LED lamps 45 are arranged at intervals of such a distance L, excessive temperature rise of the LED lamps 45 is suppressed. Therefore, deterioration of the LED lamp 45 is prevented. Therefore, the longevity of the LED lamp 45 is promoted.

LED lamp 45 includes a light emitting diode. A light emitting diode is a type of diode, and emits light due to an electroluminescence effect when a voltage is applied in the forward direction. The LED lamp 45 of this embodiment mainly emits light in the visible wavelength range. Further, the LED lamp 45 is a continuously lit lamp that emits light continuously for at least 1 second or more.

When a voltage is applied to each of the plurality of LED lamps 45 from the power supply unit 49 (FIG. 1), the LED lamp 45 emits light. The power supply section 49 individually adjusts the power supplied to each of the plurality of LED lamps 45 under the control of the control section 3 . That is, the power supply section 49 can individually adjust the light emission intensity and light emission time of each of the plurality of LED lamps 45 arranged in the LED heating section 4.

FIG. 9 is an enlarged view showing the connecting portion between the LED lamp 45 and the optical fiber 46 in FIG. Further, FIG. 10 is an enlarged view showing the connecting portion between the optical fiber 46 and the light emitting surface 47. As shown in FIG. Further, FIG. 11 is a plan view of the light emitting surface 47. Note that, in this specification, the optical fiber 46 includes not only an uncoated core and a clad, but also coated optical fibers, coated optical fibers, optical fiber cords, and the like.

As shown in FIG. 9, one end 46a of each optical fiber 46 is connected to each of the LED lamps 45 individually. A tubular connecting pipe 48 is provided around the connecting portion between the optical fiber 46 and the LED lamp 45. The connecting tube 48 is made of an elastic member, for example. By accommodating one end 46a of the optical fiber 46 and the LED lamp 45 in the connecting tube 48, each one end 46a of the optical fiber 46 is connected to the LED lamp 45.

The other end 46b of the plurality of optical fibers 46 is fixed by being inserted into a plurality of through holes 42a provided in a plate 42 made of a metal material (for example, stainless steel), thereby forming a light emitting surface 47. The plate 42 made of metal material is fixed by a support member (not shown) so that the light emitting surface 47 faces the semiconductor wafer W in the chamber 6 . At this time, the light emitting surfaces 47 are arranged in a plane so as to be parallel to each other along the main surface of the semiconductor wafer W held by the holding part 7 (that is, along the horizontal direction).

Since the optical fibers 46 have higher heat resistance than the LED lamps 45, it is also possible to arrange adjacent optical fibers 46 in contact with each other. Therefore, a plurality of through holes 42a for fixing the other ends 46b of the plurality of optical fibers 46 (in this embodiment, the other ends 46b of all the optical fibers 46) may be adjacent to each other. Further, the through hole 42a may have a honeycomb shape or a polygonal shape.

Furthermore, since the optical fiber 46 has flexibility, the shape of the optical fiber 46 can be changed to some extent. This increases the degree of freedom in arranging the light emitting surface 47. Therefore, in this embodiment, the light emitting surface 47 is formed below the semiconductor wafer W held by the holding part 7 and at a position closer to the semiconductor wafer W than the plurality of LED lamps 45 .

A filter 90 is provided between the holding part 7 and the light emitting surface 47 in the chamber 6 . In this embodiment, the filter 90 is installed directly above the light emitting surface 47. The filter 90 allows the wavelength range (half width is about 20 nm) of light emitted from the LED lamp 45 (optical fiber 46) to pass therethrough, and cuts other wavelengths. As a result, in the flash light from the flash lamp FL, light in a wavelength range that does not overlap with the wavelength range of light emitted from the LED lamp 45 (optical fiber 46) enters from the light emitting surface 47 and reaches the LED lamp 45. is prevented. Thereby, damage to the LED lamp 45 due to exposure to strong flash light can be suppressed.

A water filter may be employed as the filter 90. However, the filter 90 is not limited to this, and the filter 90 transmits light with a wavelength of 350 nm or more and less than 1000 nm (1 μm), and blocks or attenuates light with a wavelength of 1000 nm (1 μm) or more and 4000 nm (4 μm) or less. It is preferable. As such a filter 90, for example, a so-called optical filter may be used. An optical filter that can be used as the filter 90 is, for example, a band pass filter or a short wavelength pass filter. More specifically, an optical filter is a transparent base material such as glass, quartz, or resin with a dielectric or metal multilayer film attached thereto. Optical filters that utilize the property that the transmission characteristics of light change due to the interference of reflections that occur at the interfaces of multilayer films, and that transmit only light in a specific wavelength range by adjusting the material, thickness, and number of layers of the multilayer film. can be obtained. Therefore, by appropriately adjusting the material, film thickness, and number of layers of the multilayer film, it is possible to transmit light with a wavelength of 350 nm or more and less than 1000 nm (1 μm), while blocking or reducing light with a wavelength of 1000 nm (1 μm) or more and 4000 nm (4 μm) or less. It is possible to create optical filters that emit light. Note that, depending on the emission wavelength range of the LED lamp 45, it is preferable to obtain an optical filter that transmits light in the emission wavelength range.

Alternatively, a quartz plate on which a thin film of metal (for example, silver (Ag)) is formed by sputtering may be used as the filter 90. Such a filter 90 also transmits light with a wavelength of 350 nm or more and less than 1000 nm (1 μm), and blocks or attenuates light with a wavelength of 1000 nm (1 μm) or more and 4000 nm (4 μm) or less. Therefore, by providing such a filter 90 between the light emitting surface 47 and the semiconductor wafer W, the radiant light from the semiconductor wafer W can be prevented from reaching the light emitting surface 47 and damage to the LED lamp 45 can be achieved in the same way as described above. can be prevented. Note that a thin metal film may be formed on the quartz lower chamber window 64 to function as a filter.

The control unit 3 controls the various operating mechanisms described above provided in the heat treatment apparatus 1. The hardware configuration of the control unit 3 is similar to that of a general computer. That is, the control unit 3 includes a CPU, which is a circuit that performs various calculation processes, a ROM, which is a read-only memory that stores basic programs, a RAM, which is a readable and writable memory that stores various information, and control software and data. It has a magnetic disk for storing data. Processing in the heat treatment apparatus 1 progresses 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 LED heating section 4, flash heating section 5, and chamber 6 due to thermal energy generated from the LED lamp 45 and flash lamp FL during heat treatment of the semiconductor wafer W. Therefore, it is equipped with various cooling structures. For example, the wall of the chamber 6 is provided with a water cooling pipe (not shown). Further, the LED heating section 4 and the flash heating section 5 have an air-cooled structure that forms a gas flow inside to exhaust heat. Furthermore, 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 section 5 and the upper chamber window 63.

Next, processing operations in the heat processing apparatus 1 will be explained. The semiconductor wafer W to be processed is a silicon (Si) semiconductor substrate into which impurities have been implanted by ion implantation as a pre-process. Activation of the impurities is performed by annealing treatment by the heat treatment apparatus 1. The processing procedure of the semiconductor wafer W described below proceeds as the control unit 3 controls each operating mechanism of the heat treatment apparatus 1.

First, prior to processing the semiconductor wafer W, the air supply valve 84 is opened, and the exhaust valve 89 is opened to start supplying and exhausting air into the chamber 6. When the valve 84 is opened, nitrogen gas is supplied from the gas supply hole 81 to the heat treatment space 65 . Further, 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 via the transfer opening 66 by a transfer robot outside the apparatus. At this time, there is a risk that the atmosphere outside the apparatus will be drawn in as the semiconductor wafer W is carried in. However, since nitrogen gas continues to be supplied to the chamber 6, the nitrogen gas may flow out from the transfer opening 66, causing such a situation. Entrainment of external atmosphere can be suppressed to a minimum.

The semiconductor wafer W carried in by the transfer robot advances to a position directly above the holding section 7 and stops. When the pair of transfer arms 11 of the transfer mechanism 10 horizontally move from the retracted position to the transfer operation position and rise, the lift pins 12 pass through the through holes 79 and protrude from the upper surface of the holding plate 75 of the susceptor 74. and receives the semiconductor wafer W. At this time, the lift pins 12 rise 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. Then, by lowering the pair of transfer arms 11, the semiconductor wafer W is transferred from the transfer mechanism 10 to the susceptor 74 of the holding section 7, and is held from below in a horizontal position. 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 unit 7 with the patterned and impurity-injected surface facing upward. 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 that have descended below the susceptor 74 are moved to a 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 position by the susceptor 74 of the holding unit 7 formed of quartz, the plurality of LED lamps 45 of the LED heating unit 4 are turned on to start preheating (assist heating). be done. The light emitted from the plurality of LED lamps 45 passes through the optical fiber 46 and then is emitted from the light emitting surface 47. The light emitted from the light emitting surface 47 passes through the filter 90, the lower chamber window 64 made of quartz, and the susceptor 74 in order, and is irradiated onto the lower surface of the semiconductor wafer W. By receiving light irradiation from the LED lamp 45 (light emitting surface 47), the semiconductor wafer W is preheated and its temperature increases. Note that since the transfer arm 11 of the transfer mechanism 10 is retracted inside the recess 62, it does not interfere with the heating by the LED lamp 45.

As described above, when the plurality of LED lamps 45 are turned on and the temperature of the semiconductor wafer W starts to rise, the temperature of the semiconductor wafer W is measured by the radiation thermometer 20. The measured temperature of the semiconductor wafer W is transmitted to the control section 3. The control unit 3 monitors whether the temperature of the semiconductor wafer W, which is heated by light irradiation from the LED lamp 45, reaches a predetermined preheating temperature T1, and controls the power supply unit 49 to turn on the LED lamp 45. Adjust the output of That is, the control unit 3 feedback-controls the output of the LED lamp 45 based on the measured 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. (600° C. in this embodiment), at which there is no fear that impurities added to the semiconductor wafer W will be diffused by heat. .

In this embodiment, the semiconductor wafer W is irradiated with light having a wavelength of 1000 nm (1 μm) or less from the LED lamp 45 via the optical fiber 46 . Regarding the spectral absorption rate of the silicon semiconductor wafer W, in a low temperature range of 500° C. or lower, the absorption rate of infrared light having a wavelength of more than 1 μm is low, but the absorption rate of light having a wavelength of 1000 nm (1 μm) or less is relatively high. That is, even in a low temperature range of 500° C. or lower, the semiconductor wafer W satisfactorily absorbs the light emitted from the LED lamp 45 through the optical fiber 46. Therefore, even when the temperature of the semiconductor wafer W is 500° C. or lower in the initial stage of preheating, the semiconductor wafer W can be efficiently heated by the LED lamps 45.

Furthermore, a lower chamber window 64 of quartz exists between the LED heating section 4 and the holding section 7. Therefore, the light emitted from the LED lamp 45 after passing through the optical fiber 46 passes through the lower chamber window 64 made of quartz, and then is irradiated onto the semiconductor wafer W. Regarding the spectral transmittance of quartz, although the transmittance of light in a relatively long wavelength range is low, the transmittance of light with a wavelength of 900 nm or less is high. Therefore, the light emitted from the LED lamp 45 through the optical fiber 46 is hardly absorbed by the lower chamber window 64. Therefore, the semiconductor wafer W can be heated more efficiently by the LED lamp 45.

After the temperature of the semiconductor wafer W reaches the preheating temperature T1, the control section 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 LED lamp 45 to bring the temperature of the semiconductor wafer W almost to the preheating temperature. The heating temperature is maintained at T1.

When the temperature of the semiconductor wafer W reaches the preheating temperature T1 and a predetermined time has elapsed, 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 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 heads into the chamber 6. Flash heating of the semiconductor wafer W is performed by the irradiation.

Since flash heating is performed by irradiating flash light from the flash lamp FL, the surface temperature of the semiconductor wafer W can be raised in a short time. In other words, the flash light emitted from the flash lamp FL has an extremely short irradiation time of 0.1 milliseconds or more and 100 milliseconds or less, in which electrostatic energy previously stored in a capacitor is converted into an extremely short light pulse. It's 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, instantaneously rises to the processing temperature T2 of 1000° C. or higher, and the impurities implanted into the semiconductor wafer W are activated. After that, the surface temperature drops rapidly. In this way, the heat treatment apparatus 1 can raise and lower the surface temperature of the semiconductor wafer W in an extremely short time, so that the impurity can be activated while suppressing the diffusion of the impurity implanted into the semiconductor wafer W due to heat. I can do it. Note that the time required for the activation of impurities is extremely short compared to the time required for their thermal diffusion, so activation will not occur even during a short period of 0.1 to 100 milliseconds in which no diffusion occurs. Complete.

After the flash heating process is completed, the LED lamp 45 is turned off after a predetermined period of time has elapsed. As a result, the temperature of the semiconductor wafer W is rapidly lowered 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 the temperature of the semiconductor wafer W has decreased to a predetermined temperature based on the measurement result of the radiation thermometer 20.

After the temperature of the semiconductor wafer W falls below a predetermined temperature, the pair of transfer arms 11 of the transfer mechanism 10 move horizontally again from the retracted position to the transfer operation position and rise, so that the lift pins 12 move toward the susceptor 74. It protrudes from the upper surface and receives the heat-treated semiconductor wafer W from the susceptor 74. Subsequently, the transfer opening 66 that had been closed by the gate valve 185 is opened, and the semiconductor wafer W placed on the lift pins 12 is carried out from the chamber 6 by a transfer robot outside the apparatus, and the semiconductor wafer W is heated. Complete.

<Second embodiment>
A second embodiment of the present invention will be described below. FIG. 12 is a cross-sectional view schematically showing the configuration of a heat treatment apparatus 201 in the second embodiment.

The heat treatment apparatus 201 in the second embodiment includes an upper LED heating part 205 above the chamber 6 in place of the flash heating part 5 of the heat treatment apparatus 1 in the first embodiment. The upper LED heating section 205 has the same configuration as the LED heating section 4. That is, the upper LED heating section 205 includes a plurality of LED lamps 245. The upper LED heating section 205 is also controlled by the control section 3.

The upper LED heating section 205 includes a plurality of LED lamps 245, a plurality of optical fibers 246, a light emitting surface 247, and a disk-shaped mounting plate 244 on which the plurality of LED lamps 245 are arranged inside the housing 241. Equipped with. The light emitting surface 247 is formed by inserting and fixing optical fibers 246 into a plurality of through holes 242a provided in a plate 242 made of a metal material (for example, stainless steel). The upper LED heating section 205 heats the semiconductor wafer W by irradiating the heat treatment space 65 from above the chamber 6 through the upper chamber window 63 with light passing through the optical fiber 246 from the plurality of LED lamps 245 .

When a voltage is applied to each of the plurality of LED lamps 245 from the power supply unit 249 (FIG. 12), the LED lamp 245 emits light. The power supply section 249 individually adjusts the power supplied to each of the plurality of LED lamps 245 under the control of the control section 3 . That is, the power supply section 249 can individually adjust the light emission intensity and light emission time of each of the plurality of LED lamps 245 arranged in the upper LED heating section 205.

Note that in the second embodiment, the flash heating section 5 is not provided. Therefore, the filter 90 that cuts off the wavelength caused by the flash lamp FL is not necessary. Similarly, the upper LED heating section 205 does not require a filter.

<Third embodiment>
A third embodiment of the present invention will be described below. FIG. 13 is a cross-sectional view schematically showing the configuration of a heat treatment apparatus 301 in the third embodiment.

The heat treatment apparatus 301 according to the third embodiment includes an LED heating section 304 instead of the LED heating section 4 of the heat treatment apparatus 1 according to the first embodiment. The LED heating section 304 includes a plurality of light emitting surfaces 347. Each light emitting surface 347 is fixed and formed by inserting the other end portions of the plurality of optical fibers 46 into a plurality of through holes 342a provided in a plate 342 made of a metal material (for example, stainless steel). The metal material plate 342 is fixed by a support member (not shown) so that the light emitting surface 347 faces the semiconductor wafer W direction, similarly to the metal material plate 42 of the first embodiment. At this time, the light emitting surfaces 347 are arranged in a plane so as to be parallel to each other along the main surface of the semiconductor wafer W held by the holding part 7 (that is, along the horizontal direction).

The through holes 342a provided in the metal plate 342 are mostly provided at positions corresponding to the ends of the semiconductor wafer W where the temperature during heating tends to be low. That is, the other ends 46b of the plurality of optical fibers 46 are mostly arranged at positions corresponding to the ends of the semiconductor wafer W, and a light emitting surface 347 is formed. Thereby, according to the heat treatment apparatus 301 in the third embodiment, the in-plane uniformity of the heating temperature of the semiconductor wafer W is improved.

<Fourth embodiment>
A fourth embodiment of the present invention will be described below. FIG. 14 is an enlarged view showing the connecting portion between the LED lamp 45 and the optical fiber 46 in the heat treatment apparatus 401 in the fourth embodiment.

In the heat treatment apparatus 401 of the fourth embodiment, a condenser lens 443 that condenses light is interposed between one end 46a of each of the plurality of optical fibers 46 and the LED lamp 45. This increases the transmission rate of light from the LED lamp 45 to the optical fiber 46. Therefore, the light from the LED lamps 45 is emitted to the semiconductor wafer W more efficiently. Thereby, the semiconductor wafer W can be heated even more efficiently.

<About the effects produced by the embodiments described above>
Next, examples of effects produced by the embodiment described above will be shown. In addition, in the following description, the effects will be described based on the specific configurations shown in the embodiments described above, but examples will not be included in the present specification to the extent that similar effects are produced. may be replaced with other specific configurations shown.

Further, the replacement may be made across multiple embodiments. That is, the respective configurations shown as examples in different embodiments may be combined to produce similar effects.

The heat treatment apparatuses of the embodiments described above are the heat treatment apparatuses 1, 201, 301, and 401 that heat the semiconductor wafer W by irradiating the semiconductor wafer W with light. The heat treatment apparatus 1, 201, 301, 401 includes a chamber 6 that accommodates a semiconductor wafer W, a plurality of LED lamps 45 that emit light, and a plurality of optical fibers 46 individually connected to each of the plurality of LED lamps 45. , is provided. Furthermore, in the heat treatment apparatus 1, 201, 301, 401, one end 46a of each of the plurality of optical fibers 46 is connected to the LED lamp 45, and the other end 46b of the plurality of optical fibers 46 is arranged in a planar manner to form a light emitting surface. Form 47.

According to such heat treatment apparatus 1, 201, 301, 401, since the light emitting surface 47 is formed by bundling the plurality of optical fibers 46 individually connected to each of the plurality of LED lamps 45, the light emitting surface 47 is formed. The intensity per unit area of the light emitted from the light emitting surface 47 can be increased while the interval is set to be the distance L or more. Therefore, it is possible to efficiently heat the semiconductor wafer W while preventing an excessive temperature rise of the LED lamps 45.

Further, since the optical fiber 46 has flexibility, the degree of freedom in arranging the light emitting surface 47 increases. By forming the light emitting surface 47 at a position closer to the semiconductor wafer W than the LED lamp 45, attenuation of light can be suppressed.

Furthermore, in the heat treatment apparatuses 1, 201, 301, and 401, the light emitting surface 47 is arranged below the semiconductor wafer W. Therefore, the semiconductor wafer W can be preheated efficiently.

Furthermore, in the heat treatment apparatus 201, the light emitting surface 47 is also arranged above the semiconductor wafer W. Therefore, the semiconductor wafer W can be heat-treated using only the LED lamps 45. Therefore, the overall device configuration and control of the heat treatment apparatus 201 is simplified.

Further, in the heat treatment apparatus 401, a condenser lens 443 that condenses light is interposed between one end 46a of each of the plurality of optical fibers 46 and the LED lamp 45. Therefore, according to the heat treatment apparatus 401, the light from the LED lamps 45 is emitted to the semiconductor wafer W more efficiently. Thereby, the semiconductor wafer W can be heated even more efficiently.

Moreover, in the heat treatment apparatuses 1, 201, 301, and 401, heating is performed by a plurality of LED lamps 45. Therefore, the semiconductor wafer W can be heated even more efficiently.

Further, in the heat treatment apparatus 1, 201, 301, 401, the plurality of LED lamps 45 are arranged on the mounting plate 44. Furthermore, the heat treatment apparatuses 1, 201, 301, and 401 further include a cooling mechanism that cools the mounting plate 44. Therefore, cooling of the LED lamp 45 is promoted. Thereby, excessive temperature rise of the LED lamp 45 can be prevented.

Further, the heat treatment apparatuses 1, 301, and 401 further include a flash lamp FL that heats the semiconductor wafer W by irradiating it with flash light. Therefore, the temperature of the semiconductor wafer W can be rapidly raised.

Further, the heat treatment apparatus 1, 301, 401 includes a filter 90 between the light emitting surface 47, 347 and the semiconductor wafer W, which cuts light of a predetermined wavelength from the light emitted from the flash lamp FL. Therefore, the flash light from the flash lamp FL is prevented from reaching the LED lamp 45 from the light emitting surface 47, 347. Therefore, damage to the LED lamp 45 can be prevented.

<About modifications of the embodiment described above>
In the embodiments described above, the materials, materials, dimensions, shapes, relative arrangement relationships, implementation conditions, etc. of each component may also be described, but these are only one example in all aspects. However, it is not limited to what is described in the specification of this application.

Accordingly, countless variations and equivalents, not illustrated, are envisioned within the scope of the technology disclosed herein. For example, when at least one component is modified, added, or omitted, or when at least one component in at least one embodiment is extracted and combined with a component in another embodiment. shall be included.

In the above embodiment, the light emitting surfaces 47, 247, 347 are formed inside the housing 41, but the light emitting surfaces 47, 247, 347 are formed outside the housing 41. There may be. For example, it may be formed inside the chamber 6. In this case, since the lower chamber window 64 made of quartz is not required, the bottom wall of the chamber 6 may be made of stainless steel, and the bundle of the plurality of optical fibers 46 may pass through the bottom wall.

Further, in the above embodiment, a configuration is adopted in which the filter 90 is placed directly above the light emitting surface 47, 347, but the filter 90 is placed directly below the lower chamber window 64 installed above the light emitting surface 47. may be installed. Furthermore, the filter 90 may be installed within the chamber 6 and directly above the lower chamber window 64.

Further, in the embodiment described above, the LED lamp 45 is used as the light emitting element, but the present invention is not limited to this. The light emitting element is not limited to the LED lamp 45, and may be a laser diode, for example.

Further, in the above-described embodiment, the plurality of LED lamps 45 are arranged concentrically, but the present invention is not limited to this. For example, a plurality of LED lamps 45 may be arranged at equal intervals in a grid pattern.

Further, in the embodiment described above, the other ends of the plurality of optical fibers 46, 246 are inserted into the plurality of through holes 42a, 242a, 342a provided in the plates 42, 242, 342 made of metal material (for example, stainless steel). However, the present invention is not limited to this. For example, they may be fixed by being bundled with a binding band. The binding band may be fixed by a support member (not shown) such that the light emitting surface 47 faces the semiconductor wafer W in the chamber 6.

Further, in the above-described embodiment, the LED lamps 45 arranged below the semiconductor wafer W and the LED lamps 245 arranged above the semiconductor wafer W are employed, but the present invention is not limited thereto. The LED lamp may be arranged on the side surface of the semiconductor wafer W, or a configuration may be adopted in which the light emitting surface connected to the LED lamp is arranged on the side surface of the semiconductor wafer W.

Further, FIG. 15 is a cross-sectional view schematically showing the configuration of a heat treatment apparatus 501 in a modification of the first embodiment. Moreover, FIG. 16 is a plan view schematically showing the plane of the chamber side portion 561 in FIG. 15. As shown in FIG.

In the heat treatment apparatus 1 of the first embodiment, the light emitting surfaces 47 are arranged in a plane parallel to each other along the main surface of the semiconductor wafer W, but the arrangement of the light emitting surfaces 47 is not limited to this. For example, a configuration like a heat treatment apparatus 501 shown in FIG. 15 may be adopted.

Specifically, as shown in FIG. 15, the other ends of some of the optical fibers 546 connected from some of the LED lamps 545 are inserted into the chamber side part 561, so that the light emitting surface 547 formed by the chamber 506 is inserted into the chamber side part 561. may be directed toward the semiconductor wafer W from the side thereof.

Specifically, a heating through hole 561a is formed in the chamber side portion 561. The heating through hole 561a is a cylindrical hole for guiding an optical fiber 546 and a light emitting surface 547, which will be described later, into the inside of the chamber 506. A transparent window 521 made of quartz that transmits light from the light emitting surface 547 is attached to the end of the heating through hole 561a facing the heat treatment space 565.

The light emitting surface 547 is arranged in the heating through hole 561a so as to irradiate light in the direction of the semiconductor wafer W. At this time, the light emitting surface 547 is preferably arranged so as to face the peripheral edge or side of the semiconductor wafer W. The reason for this is as follows. It is thought that heat dissipation is particularly likely to occur at the peripheral portion of the semiconductor wafer W, and the temperature of the peripheral portion of the semiconductor wafer W tends to be lower than that of the central portion. Therefore, if the amount of light directed toward the peripheral edge of the semiconductor wafer W is greater than the amount of light directed toward the center of the semiconductor wafer W, the in-plane temperature uniformity of the semiconductor wafer W improves. be.

Moreover, as shown in FIG. 16, the heating through-holes 561a are formed at a plurality of locations (six locations in the example of FIG. 16) around the chamber side portion 561. Furthermore, from the viewpoint of improving the in-plane temperature uniformity of the semiconductor wafer W, it is preferable that a plurality of heating through holes 561a be formed around the semiconductor wafer W at approximately equal intervals.

Although not shown in FIGS. 15 and 16, a filter 90 may be provided between the light emitting surface 547 and the semiconductor wafer W.

In addition, in the embodiments described above, if a material name is stated without being specified, unless a contradiction occurs, the material may contain other additives, such as an alloy. shall be included.

1,201,301,401,501 Heat treatment device 3 Control unit 4,304 LED heating unit 5 Flash heating unit 6,506 Chamber 7 Holding unit 10 Transfer mechanism 11 Transfer arm 12 Lift pin 13 Horizontal movement mechanism 14 Lifting mechanism 20 Radiation Thermometer 21,521 Transparent window 41,51,241 Housing 42,242,342 Plate 42a, 242a, 342a Through hole 44,244 Mounting plate 44a Circulation path 44b External pump 45,245,545 LED lamp 46,246, 546 Optical fiber 46a One end 46b Other end 47,247,347,547 Light emitting surface 48 Connection tube 49,249 Power supply section 52 Reflector 53 Lamp light emission window 61,561 Chamber side 61a Through hole 62 Recess 63 Upper chamber window 64 Bottom Side chamber window 65, 565 Heat treatment space 66 Transfer opening 68, 69 Reflection ring 71 Base ring 72 Connection portion 74 Susceptor 75 Holding plate 75a Holding surface 76 Guide ring 77 Substrate support pin 78 Opening 79 Through hole 81 Gas supply hole 84 , 89 Valve 85 Processing gas supply source 86 Gas exhaust hole 87 Buffer space 88 Gas exhaust pipe 90 Filter 185 Gate valve 190 Exhaust part 205 Upper LED heating part 443 Condenser lens 561a Heating through hole CX Central axis FL Flash lamp L Distance T1 Preheating temperature T2 Processing temperature W Semiconductor wafer

Claims (9)

A heat treatment apparatus that heats a substrate by irradiating the substrate with light,
a chamber containing the substrate;
A plurality of light emitting elements that emit light,
a plurality of optical fibers individually connected to each of the plurality of light emitting elements;
Equipped with
One end of each of the plurality of optical fibers is connected to the light emitting element, and the other end of the plurality of optical fibers is arranged in a plane to form a light emitting surface. The heat treatment apparatus according to claim 1,
In the heat treatment apparatus, the light emitting surface is formed at a position closer to the substrate than the plurality of light emitting elements. The heat treatment apparatus according to claim 2,
A heat treatment apparatus, wherein the light emitting surface is disposed below the substrate. The heat treatment apparatus according to claim 3,
The heat treatment apparatus, wherein the light emitting surface is also placed above the substrate. The heat treatment apparatus according to any one of claims 1 to 4,
A heat treatment apparatus, wherein a condenser lens for condensing light is interposed between the one end of each of the plurality of optical fibers and the light emitting element. The heat treatment apparatus according to any one of claims 1 to 5,
A heat treatment apparatus, wherein the plurality of light emitting elements are a plurality of light emitting diodes. The heat treatment apparatus according to claim 6,
The plurality of light emitting diodes are arranged on a mounting plate,
A heat treatment apparatus further comprising a cooling mechanism that cools the mounting plate. The heat treatment apparatus according to any one of claims 1 to 7,
A heat treatment apparatus further comprising a flash lamp that heats the substrate by irradiating the substrate with flash light. The heat treatment apparatus according to claim 8,
A heat treatment apparatus comprising: a filter that cuts light of a predetermined wavelength from light emitted from the flash lamp between the light emitting surface and the substrate.

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