JP2009231662A - Heat treatment equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide heat treatment equipment can improve within-wafer nonuniformity in temperature distribution on a substrate in heat treatment. <P>SOLUTION: Toward the substrate W held by a holding section 2, light is radiated from a first photoirradiation section 3 to perform preheating treatment, and a flash is irradiated from a second photoirradiation section 4 to perform flash heating treatment. Furthermore, light is radiated toward a specific region on the substrate W from a lamp 61 for adjustment arranged at a height position separated from the height position of the upper surface of the substrate held by the holding section 2 by a separation distance H on the inner wall surface of a chamber side section 51. Light is radiated to a region that easily becomes a cold spot, thus suppressing the occurrence of the cold spot, and hence improving within-wafer nonuniformity in temperature distribution. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a heat treatment apparatus for heat-treating a semiconductor wafer, a glass substrate for a liquid crystal display device or the like (hereinafter simply referred to as “substrate”), particularly a heat treatment apparatus for heat-treating the substrate. The present invention relates to a heat treatment apparatus for heating.

  Conventionally, a lamp annealing apparatus using a halogen lamp has been generally used in an ion activation process of a substrate after ion implantation. In such a lamp annealing apparatus, ion activation of the substrate is performed by heating (annealing) the substrate to a temperature of about 1000 ° C. to 1100 ° C., for example. In such a heat treatment apparatus, the temperature of the substrate is raised at a rate of several hundred degrees per second by using the energy of light irradiated from the halogen lamp.

  On the other hand, in recent years, as semiconductor devices have been highly integrated, it is desired to reduce the junction depth as the gate length becomes shorter. However, even when ion activation of the substrate is performed using the above-mentioned lamp annealing apparatus that heats the substrate at a rate of several hundred degrees per second, ions such as boron and phosphorus implanted into the substrate are diffused deeply by heat. It has been found that a phenomenon occurs. When such a phenomenon occurs, there is a concern that the junction depth becomes deeper than required, which hinders good device formation.

  Therefore, a technique has been proposed in which only the surface of the substrate into which ions are implanted is heated in an extremely short time (several milliseconds or less) by irradiating the surface of the substrate with flash light using a xenon flash lamp or the like. Yes. 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 the silicon substrate. Therefore, when the substrate is irradiated with flash light from the xenon flash lamp, the substrate can be rapidly heated with little transmitted light. It has also been found that if the flash irradiation is performed for a very short time of several milliseconds or less, only the vicinity of the surface of the substrate can be selectively heated. For this reason, if the temperature is raised for a very short time by a xenon flash lamp, only the ion activation can be performed without diffusing ions deeply. A configuration example of a heat treatment apparatus using such a xenon flash lamp is described in Patent Document 1, for example.

JP 2004-140318 A

  In a heat treatment apparatus using a xenon flash lamp, the area where a plurality of xenon flash lamps are arranged is considerably larger than the area of the substrate, but the illuminance at the peripheral edge of the substrate is nevertheless on the inner side. Compared to the illuminance, it was expected to decrease somewhat. In particular, with a large-diameter substrate having a diameter of 300 mm, the degree of decrease in illuminance at the periphery of the wafer was large, and the in-plane illuminance distribution was not good. Further, it has been found that there is not only nonuniform temperature distribution along the radial direction of the wafer but also nonuniform temperature distribution along the circumferential direction of the same radius. Specifically, a low temperature region called a cold spot may occur only in a part of the peripheral edge of the substrate.

  In addition, before performing flash heating with a xenon flash lamp, the substrate is preheated using a hot plate, a halogen lamp, or the like. Although the hot plate has an advantage that the temperature of the substrate can be raised safely and uniformly to some extent, the application range is limited because the temperature that can be raised is limited. On the other hand, if a halogen lamp is used, a temperature increase of 600 degrees or more can be realized. If the substrate can be preliminarily heated to a high temperature region of 600 ° C. or higher before flash heating, the temperature increase range required for flash heating can be reduced accordingly. That is, the energy to be given to the substrate by the xenon flash lamp can be reduced. This makes it possible to reduce the thermal stress generated in the substrate during flash heating, and to prevent the occurrence of cracks in the substrate during flash heating. However, with a configuration using a halogen lamp, it is very difficult to raise the temperature of the substrate uniformly. Even in the preliminary temperature increase, only a part of the surface area of the substrate has a high temperature region or a cold spot called a hot spot. It will occur.

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

  The invention of claim 1 is a heat treatment apparatus for heat-treating a substrate by irradiating the substrate with light, the column-shaped housing, and the bottom surface of the column within the housing. Holding means for holding the substrate in a posture parallel to each other, and one or more light irradiation means for irradiating light toward the substrate from a position separated from the substrate held by the holding means by a predetermined distance; Each of the one or more light irradiating means for irradiating light from a predetermined plane parallel to the bottom surface of the column body toward the entire substrate, And one or more adjustment light irradiating means for irradiating light from a predetermined position on the side surface of the pillar toward the local region of the substrate.

  The invention according to claim 2 is a heat treatment apparatus for heat-treating a substrate by irradiating the substrate with light, the column-shaped housing, and the bottom surface of the column within the housing. Holding means for holding the substrate in a posture parallel to each other, and one or more light irradiation means for irradiating light toward the substrate from a position separated from the substrate held by the holding means by a predetermined distance; Each of the one or more light irradiating means for irradiating light from a predetermined plane parallel to the bottom surface of the column body toward the entire substrate, And one or more adjustment light irradiating means for irradiating light toward a local region of the substrate from the same plane as the predetermined processing light irradiating means among the one or more processing light irradiating means. .

A third aspect of the present invention is the heat treatment apparatus according to the second aspect, wherein each of the one or more adjustment light irradiating means is a light source of a type different from a light source included in the predetermined processing light irradiating means,
Is provided.

  A fourth aspect of the present invention is the heat treatment apparatus according to the second or third aspect, wherein each of the one or more adjustment light irradiation means is different from a light emission shape of a light source provided in the predetermined processing light irradiation means. A light-emitting light source.

  Invention of Claim 5 is the heat processing apparatus in any one of Claim 1 to 4, Comprising: The irradiation direction of the light of the predetermined | prescribed adjustment light irradiation means among the one or more adjustment light irradiation means is changed. Irradiation direction changing means.

  A sixth aspect of the present invention is the heat treatment apparatus according to the fifth aspect, wherein the irradiation direction when a low temperature region is generated in a part of the substrate in the heat treatment of the substrate by the one or more processing light irradiation means. Irradiation position control means for controlling the changing means to cause the predetermined adjustment light irradiating means to emit light toward the low temperature region.

  A seventh aspect of the present invention is the heat treatment apparatus according to any one of the first to sixth aspects, wherein a light beam emitted from a predetermined adjustment light irradiation unit among the one or more adjustment light irradiation units is spread. Irradiation area size changing means for changing the size of the adjustment light irradiation area, which is an area where the light beam emitted from the predetermined adjustment light irradiation means is incident on the substrate, by changing the angle.

  Invention of Claim 8 is the heat processing apparatus of Claim 7, Comprising: The said irradiation area size change means arrange | positions with the attitude | position which made the optical axis correspond with the irradiation direction of the light of the said predetermined adjustment light irradiation means An adjustment lens, and an adjustment lens position changing unit that changes a separation distance between the predetermined adjustment light irradiation unit and the adjustment lens by moving the adjustment lens along the optical axis; .

  Invention of Claim 9 is the heat processing apparatus of Claim 7 or 8, Comprising: When the low-temperature area | region arises in a part of said board | substrate in the heat processing of the board | substrate by the said one or more process light irradiation means, Irradiation area control means for controlling the irradiation area size changing means to change the spread angle so that the adjustment light irradiation area has a size corresponding to the low temperature area.

  A tenth aspect of the present invention is the heat treatment apparatus according to any one of the first to ninth aspects, wherein the predetermined adjustment light irradiation means of the one or more adjustment light irradiation means includes a halogen lamp. .

  Invention of Claim 11 is the heat processing apparatus in any one of Claim 1-9, Comprising: The predetermined | prescribed adjustment light irradiation means of the one or more adjustment light irradiation means is equipped with a laser light source. .

  A twelfth aspect of the present invention is the heat treatment apparatus according to any one of the first to eleventh aspects, wherein a predetermined processing light irradiation means of the one or more processing light irradiation means emits flash light. A lamp.

  A thirteenth aspect of the present invention is the heat treatment apparatus according to any one of the first to twelfth aspects, wherein the predetermined processing light irradiation means among the one or more processing light irradiation means includes a halogen lamp. .

  According to the first and second aspects of the invention, in addition to the processing light irradiating means for irradiating the entire substrate, the adjustment light irradiating means for irradiating the light toward the local region of the substrate is provided. Even when a non-uniform region of the temperature distribution is generated on the substrate in the heat treatment by the light irradiation means, the temperature distribution non-uniformity is eliminated by locally heating the substrate using the adjustment light irradiation means. Can do. Thereby, the in-plane uniformity of the temperature distribution on the substrate during the heat treatment can be improved.

  In particular, according to the first aspect of the present invention, the adjusting light irradiating means and the processing light irradiating means are arranged on different surfaces, so that the adjusting light irradiating means is thermally affected by the processing light irradiating means. Hateful.

  According to the invention of claim 3, the light source provided in the adjustment light irradiating means for irradiating light toward the local region of the substrate from the same plane as the predetermined processing light irradiating means is the predetermined processing light irradiating means. Therefore, it is possible to effectively eliminate the non-uniformity of the temperature distribution generated in the heat treatment by the predetermined processing light irradiation means.

  According to invention of Claim 4, the light emission shape of the light source with which the adjustment light irradiation means which irradiates light to the local area | region of a board | substrate from the same plane as a predetermined processing light irradiation means is the said predetermined processing light Since it is different from the light emission shape of the light source provided in the light irradiating means, it is possible to effectively eliminate the non-uniformity of the temperature distribution generated in the heat treatment by the predetermined processing light irradiating means.

  According to the fifth and sixth aspects of the invention, since the irradiation direction changing means for changing the light irradiation direction of the adjustment light irradiation means is provided, the emission direction of the light from the adjustment light irradiation means can be arbitrarily changed. . Therefore, even when a non-uniform temperature distribution region occurs in the substrate in the heat treatment by the processing light irradiation unit, the adjustment light irradiation unit can reliably irradiate the region with light. Thereby, the in-plane uniformity of the temperature distribution on the substrate during the heat treatment can be greatly improved.

  According to invention of Claims 7-9, the adjustment light which is an area | region where the light ray radiate | emitted from the adjustment light irradiation means injects on a board | substrate by changing the divergence angle of the light ray radiate | emitted from the adjustment light irradiation means. Since the irradiation area size changing means for changing the size of the irradiation area is provided, the size of the adjustment light irradiation area can be arbitrarily adjusted. Therefore, even when a non-uniform temperature distribution region occurs in the substrate in the heat treatment by the processing light irradiation unit, the adjustment light irradiation unit can be formed with an adjustment light irradiation region having a size corresponding to the region. . Thereby, the in-plane uniformity of the temperature distribution on the substrate during the heat treatment can be greatly improved.

  A heat treatment apparatus according to an embodiment of the present invention will be described with reference to the drawings. The heat treatment apparatus 100 according to the embodiment of the present invention is a flash lamp annealing apparatus that heats a substantially circular substrate W by irradiating flash light (flash light).

<1. Overall configuration of heat treatment equipment>
First, an overall configuration of a heat treatment apparatus according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a side sectional view showing the configuration of the heat treatment apparatus 100. 2 (a) and 2 (b) are longitudinal sectional views of the heat treatment apparatus 100 as seen from the directions of arrows Q1 and Q2 in FIG. 1, respectively.

  The heat treatment apparatus 100 includes a chamber 5 having a columnar shape (in this embodiment, a hexagonal column). The chamber 5 includes a hexagonal cylindrical chamber side 51, a chamber lid 52 that covers the upper part of the chamber side 51, and a chamber bottom 53 that covers the lower part of the chamber side 51. A transfer opening 511 for carrying in and out the substrate W is formed in the chamber side portion 51. The transfer opening 511 can be opened and closed by a gate valve 513 that rotates about a shaft 512. The transfer opening 511 is also formed so as to penetrate a side wall surface of the reflector 1 to be described later, and is reflected through the transfer opening 511 when the gate valve 513 is placed in an open position (a virtual line position in FIG. 1). The substrate W can be carried in and out of the cylinder of the body 1 (arrow AR5). On the other hand, when the gate valve 513 is placed in the closed position (solid line position in FIG. 1), the inside of the chamber 5 is set as a sealed space.

  Further, the heat treatment apparatus 100 includes the reflector 1 formed in a cylindrical shape (more specifically, a cylindrical shape having a cross-sectional shape similar to that of the chamber side portion 51 and a hexagonal cylindrical shape in the present embodiment). The reflector 1 is disposed inside the chamber 5 and along the inner side surface of the chamber side portion 51. The reflector 1 is formed in a hexagonal cylindrical shape by six reflectors 11, and each reflector 11 is formed of a member having a sufficiently high reflectance (for example, aluminum). Alternatively, the inner surface is coated with a coating that increases reflectivity (eg, a gold non-diffusive coating). A part of the light beams emitted from the light irradiation units 3 and 4 described later are reflected by the inner surface of the reflecting plate 11 and enter the substrate W held by the holding unit 2 described later. As a result, the light energy generated from the light irradiation units 3 and 4 is used for heat treatment of the substrate W without waste.

  Further, the heat treatment apparatus 100 holds the substrate W horizontally inside the chamber 5 (that is, in a posture parallel to the chamber lid portion 52 and the chamber bottom portion 53 that form the bottom surface of the chamber 5 that is a pillar). Is provided. The holding unit 2 is a ring-shaped member having a diameter slightly larger than the diameter of the substrate W, and a plurality of (for example, four) support members 21 that support the back surface of the substrate W with dots are formed on the inner end surface thereof. Has been. The substrate W held by the holding unit 2 is supported from the back side by the plurality of support members 21.

  The heat treatment apparatus 100 is disposed inside the reflector 1 and irradiates the substrate W with light from a position separated from the substrate W held by the holding unit 2 by a predetermined distance. Three light irradiation parts 3, 4 and 6 to be heated are provided.

  The first light irradiation part (first light irradiation part 3) is from a plane parallel to the bottom surface (chamber lid part 52 and chamber bottom part 53) of the chamber 5 which is a column (more specifically, the chamber 5 Light is applied to the entire substrate W (from a plane parallel to the bottom surface and below the substrate W held by the holding unit 2 and separated from the substrate W by 100 mm or more). Then, the entire surface area of the substrate W is heated to a predetermined preheating temperature by the light energy (preheating process). The first light irradiation unit 3 includes a plurality of halogen lamps 31 and a reflector 32. The plurality of halogen lamps 31 are each a rod-shaped lamp having a long cylindrical shape, and each of the halogen lamps 31 is planar so that the longitudinal direction thereof is parallel to the main surface of the substrate W held by the holding unit 2. It is arranged. The reflector 32 is provided below the plurality of halogen lamps 31 so as to cover all of them, and the surface thereof is roughened by blasting to exhibit a satin pattern.

  The halogen lamp 31 is a filament-type light source that emits light by making the filament incandescent by energizing the filament disposed inside the glass tube. Inside the glass tube, a small amount of a halogen element (iodine, bromine, etc.) introduced 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 31 has a feature that it has a longer life than a normal incandescent bulb and can continuously radiate strong light.

  The second light irradiation unit (second light irradiation unit 4) is held by the holding unit 2 from a plane parallel to the bottom surface of the chamber 5 that is a column (more specifically, parallel to the bottom surface of the chamber 5). The light is directed toward the whole of the substrate W (more specifically, the substrate W preheated by the first light irradiation unit 3) from the upper side of the substrate W which has been separated from the substrate W by 100 mm or more. Irradiate. Then, the entire surface region of the substrate W is heated in a short time by the light energy (flash heat treatment). The second light irradiation unit 4 includes a plurality of (for example, 30) xenon flash lamps (hereinafter simply referred to as “flash lamps”) 41 and a reflector 42. The plurality of flash lamps 41 are each a rod-shaped lamp having a long cylindrical shape, and each of the flash lamps 41 is planar so that the longitudinal direction thereof is parallel to the main surface of the substrate W held by the holding unit 2. It is arranged. The reflector 42 is provided above the plurality of flash lamps 41 so as to cover all of them, and the surface thereof is roughened by blasting to exhibit a satin pattern.

  The xenon flash lamp 41 includes a glass tube in which xenon gas is sealed and an anode and a cathode connected to a capacitor at both ends thereof, a trigger electrode wound on the outer peripheral surface of the glass tube, Is provided. Since xenon gas is an electrical insulator, electricity does not flow into the glass tube under normal conditions. However, if the insulation is broken by applying a high voltage to the trigger electrode, the electricity stored in the capacitor instantaneously flows into the glass tube, and the xenon gas is heated by Joule heat at that time, and light is emitted. . In this xenon flash lamp 41, the electrostatic energy stored in advance is converted into an extremely short light pulse of 0.1 millisecond to 10 millisecond. It has the feature that it can.

  The third light irradiation unit (third light irradiation unit 6) irradiates light toward the local region of the substrate W from the side surface (chamber side portion 51) of the chamber 5 that is a column. Then, the substrate W is locally heated by the light energy. More specifically, when a low temperature region (cold spot C) is generated on the surface of the substrate W in the preheating process and the flash heating process (hereinafter simply referred to as “heat treatment”), light is directed toward the cold spot C formation region. , And the temperature of the region is locally raised, thereby eliminating the cold spot C (or preventing its occurrence). The configuration of the third light irradiation unit 6 will be specifically described later.

  In addition, between the light irradiation parts 3 and 4 and the holding | maintenance part 2, the atmosphere interruption member for putting each of the light irradiation parts 3 and 4 and the board | substrate W hold | maintained at the holding | maintenance part 2 in the isolate | separated space is provided. It may be provided. However, this atmosphere blocking member needs to be formed using a member that transmits light (for example, quartz). By providing the atmosphere blocking member, it is possible to prevent the substrate W held on the holding unit 2 from being contaminated by particles generated in the light irradiation units 3 and 4.

  In addition, the heat treatment apparatus 100 includes a control unit 91 that controls each of the above components, an operation unit 92 that is a user interface, and a display unit 93. The operation unit 92 and the display unit 93 are arranged outside the chamber 5 and receive various instructions from the user outside the chamber 5. The control unit 91 controls each component of the heat treatment apparatus 100 based on various instructions input from the operation unit 92 and the display unit 93.

<2. Configuration of third light irradiation unit 6>
The 3rd light irradiation part 6 is demonstrated concretely, continuing referring FIG. 1, FIG.

<Adjustment lamp 61>
The third light irradiation unit 6 includes an adjustment lamp 61 that is a light source that emits light toward the substrate W held by the holding unit 2. The adjustment lamp 61 is constituted by, for example, a point light source-like halogen lamp.

  The adjustment lamp 61 is an inner wall surface of the chamber side portion 51 and is disposed at a height position separated from the height position of the upper surface of the substrate held by the holding portion 2 by a predetermined distance (separation distance H). (That is, the light emission port is located inside the cylinder of the reflector 1). However, it is desirable to set the separation distance H as large as possible. This is because the incident angle θ when the light beam emitted from the adjustment lamp 61 is incident on the substrate W is relatively increased as the separation distance H is decreased, and when the incident angle θ is increased, the surface of the substrate W is increased. This is because the light beam spreads greatly and it is difficult to appropriately control the size of the adjustment light irradiation region S. (However, the “adjustment light irradiation region S” refers to a region in which the light beam emitted from the adjustment lamp 61 is incident on the substrate W held by the holding unit 2). It is desirable to dispose as high a position as possible so long as it is not affected by heat from the lamp 41. For example, when the diameter of the substrate W to be processed is 300 mm, the separation distance H is desirably 200 mm or more.

<Irradiation direction changing mechanism 62>
The third light irradiation unit 6 includes an irradiation direction changing mechanism 62 that changes the irradiation direction of light emitted from the adjustment lamp 61 by changing the posture of the adjustment lamp 61. For example, the irradiation direction changing mechanism 62 changes the position of the light exit of the adjustment lamp 61 relative to the fixed end of the adjustment lamp 61 (the end fixedly attached to the inner wall surface of the chamber side portion 51). The posture of the adjustment lamp 61 is changed. In this case, a bellows structure 611 that can be bent may be formed between the light emission port of the adjustment lamp 61 and the fixed end.

  The irradiation position control unit 911 included in the control unit 91 includes, for example, an operation unit 92 and a display unit 93 according to a detection result from a temperature sensor (not illustrated) that measures the temperature of the substrate W that has been subjected to the heat treatment. The irradiation direction changing mechanism 62 is driven and controlled in accordance with an instruction input from the operator via the operator, and the irradiation direction of the light emitted from the adjustment lamp 61 is adjusted. That is, the adjustment light irradiation area S formed on the substrate W is moved to an appropriate position (adjustment light irradiation area Sa in FIG. 1).

  For example, from a measurement result obtained by a temperature sensor or the like that measures the surface temperature of the substrate W related to the heat treatment, as shown in FIG. When it is found that a cold spot C) that is a low temperature region is formed, the irradiation position control unit 911 controls the irradiation direction changing mechanism 62 so that the light irradiated from the adjustment lamp 61 is incident on the region. Thus, the posture of the adjustment lamp 61 is adjusted. That is, the adjustment light irradiation area S formed on the substrate W by the adjustment lamp 61 is moved to the formation area of the cold spot C. The adjustment light irradiation area S is heated by the light energy emitted from the adjustment lamp 61, and the cold spot C disappears (or the generation thereof is prevented in advance).

<Irradiation area size changing mechanism 63>
The third light irradiation unit 6 changes the spread angle of the light beam emitted from the adjustment lamp 61 to thereby adjust the size of the adjustment light irradiation region S formed on the substrate W by the light emitted from the adjustment lamp 61. An irradiation area size changing mechanism 63 to be changed is provided.

  The irradiation area size changing mechanism 63 is formed by various optical systems, for example. In this embodiment, the irradiation area size changing mechanism 63 includes a lens 631 arranged in an attitude in which the optical axis thereof coincides with the direction of the light emitted from the adjustment lamp 61, and the lens 631 as the optical axis. Is provided with a lens position changing unit 632 that changes the separation distance between the adjustment lamp 61 and the lens 631. When the lens position changing unit 632 changes the distance, the degree of spread of the light beam emitted from the adjustment lamp 61 (and consequently the size of the adjustment light irradiation region S) is changed. Various lenses such as a convex lens and a concave lens can be used as the lens 631. A plurality of lenses may be used in combination.

  The irradiation region control unit 912 included in the control unit 91 includes, for example, an operation unit 92 and a display unit 93 according to a detection result from a temperature sensor (not illustrated) that measures the temperature of the substrate W that has been subjected to the heat treatment. The irradiation area size changing mechanism 63 is driven and controlled in accordance with an instruction input from the operator (more specifically, the lens position changing unit 632 is driven and controlled to separate the lens 631 and the adjustment lamp 61). By adjusting the distance to an appropriate value), the spread angle of the light beam emitted from the adjustment lamp 61 is adjusted. That is, the adjustment light irradiation area S formed on the substrate W is adjusted to an appropriate size (adjustment light irradiation area Sb in FIG. 1).

  For example, as shown in FIG. 2B, a temperature non-uniform region (in particular, a cold spot C in this case) may be formed in a specific region on the substrate W after the heat treatment based on the measurement result obtained by the temperature sensor or the like. When it becomes clear, the irradiation area control unit 912 controls the irradiation area size changing mechanism 63 to change the size of the adjustment light irradiation area S formed on the substrate W by the adjustment lamp 61 to a size corresponding to the cold spot C. change. Particularly preferably, the size is changed to the same size as the cold spot C. The adjustment light irradiation region S is heated by the light energy emitted from the adjustment lamp 61, and the cold spot C disappears (or the generation thereof is prevented in advance).

<3. Operation of heat treatment equipment>
Next, a processing procedure for the substrate W in the heat treatment apparatus 100 will be described with reference to FIG. FIG. 3 is a diagram showing a flow of processing executed in the heat treatment apparatus 100. Here, the substrate W to be processed is a semiconductor substrate to which impurities are added by an ion implantation method, and activation of the added impurities is performed by heat treatment by the heat treatment apparatus 100. The following processing operations are performed by the control unit 91 controlling each component at a predetermined timing.

  First, the substrate W after ion implantation is carried into the heat treatment apparatus 100 (step S1). More specifically, the control unit 91 controls driving means (not shown) to place the gate valve 513 in the open position. As a result, the transport opening 511 is opened. Subsequently, a transfer robot outside the apparatus carries the ion-implanted substrate W into the chamber 5 through the transfer opening 511 and places it on the holding unit 2. When the substrate W is placed on the holding unit 2, the control unit 91 controls the driving means (not shown) again to place the gate valve 513 in the closed position. As a result, the transfer opening 511 is closed and the inside of the chamber 5 is made a sealed space.

  Subsequently, the substrate W held by the holding unit 2 is preheated (step S2). More specifically, the control unit 91 controls the first light irradiation unit 3 to irradiate light toward the substrate W held by the holding unit 2. The substrate W is heated to a predetermined preheating temperature by this light energy. At this time, the light emitted from the halogen lamp 31 of the first light irradiation unit 3 is directed to the substrate W held by the holding unit 2 while being reflected directly or while being reflected by the reflecting plate 11, the reflecting cover 32, or the like. Preheating of the substrate W is performed by these light irradiations.

  By preheating the substrate W by the first light irradiation unit 3 before flash heating described later, the surface temperature of the substrate W can be easily raised to the processing temperature in flash irradiation from a flash lamp 41 described later. it can. In particular, in this embodiment, since the halogen lamp 31 is used for preheating, the substrate W is preliminarily heated to a higher temperature (for example, 600 degrees or more) region than when a hot plate or the like is used. be able to. This makes it possible to reduce the temperature rise width in flash heating, and to prevent the occurrence of cracks in the substrate in flash heating.

  Subsequently, the surface temperature of the substrate W is adjusted by performing a local heat treatment on the substrate W (step S3). More specifically, it has been found that the control unit 91 controls the third light irradiation unit 6 to easily form a specific region of the substrate W held on the holding unit 2 (for example, a cold spot C in the heat treatment). Irradiate light toward the area. This specific energy raises the specific region to a predetermined processing heating temperature, thereby improving the in-plane uniformity of the substrate W surface temperature.

  However, the irradiation position control unit 911 and the irradiation region control unit 912 drive and control the irradiation direction changing mechanism 62 and the irradiation region size changing mechanism 63, respectively, before the processing of step S3 is started, so It is assumed that the posture of the adjustment lamp 61 and the position of the lens 631 are adjusted in advance so that the adjustment light irradiation region S of a proper size is formed. For example, when it has been known in advance that a cold spot C is likely to occur in a specific region on the substrate W after the heat treatment, adjustment is performed so that the adjustment light irradiation region S is formed in the region. This adjustment only needs to be completed at the latest when the process of step S3 is started. For example, the adjustment may be performed before the process of step S1 is started. Alternatively, the temperature of the substrate surface may be measured with a temperature sensor or the like immediately before performing the local heat treatment, and adjustment may be performed based on the obtained measurement result.

  Subsequently, the substrate W held by the holding unit 2 is flash-heated (step S4). More specifically, the control unit 91 controls the second light irradiation unit 4 to irradiate flash light (flash light) toward the substrate W held by the holding unit 2. The substrate W is heated to a predetermined processing heating temperature by this light energy. At this time, a part of the light emitted from the flash lamp 41 of the second light irradiation unit 4 goes directly to the substrate W held by the holding unit 2, and the other part is once reflected on the reflecting plate 11 and the reflecting cover 42. The light travels toward the substrate W after being reflected by. The flash heating of the substrate W is performed by these flash irradiations.

  Since the flash heating is performed by flash irradiation from the flash lamp 41, the surface temperature of the substrate W can be increased in a short time. In other words, the flash light emitted from the flash lamp 41 of the second light irradiation unit 4 has an irradiation time of about 0.1 to 10 milliseconds, in which the electrostatic energy stored in advance is converted into an extremely short light pulse. It is a very short and strong flash. The surface temperature of the substrate W that is flash-heated by flash irradiation from the flash lamp 41 instantaneously increases to a predetermined processing temperature (for example, about 1000 ° C. to 1100 ° C.), and impurities added to the substrate W After being activated, the surface temperature drops rapidly. As described above, since the surface temperature of the substrate W can be raised and lowered in a very short time in the heat treatment apparatus 100, diffusion of impurities added to the substrate W due to heat (this diffusion phenomenon is caused by the profile of the impurities in the substrate W). Impurities can be activated while suppressing (also referred to as “bending”). Since the time required for activation of the added impurity is extremely short compared to the time required for thermal diffusion, activation is possible even for a short time when no diffusion of about 0.1 millisecond to 10 millisecond occurs. Is completed.

  When the above processing is completed, the substrate W is unloaded from the heat treatment apparatus 100 (step S5). More specifically, the controller 91 controls the driving means (not shown) to place the gate valve 513 in the open position. Subsequently, a transfer robot outside the apparatus carries the substrate W out of the chamber 5 through the transfer opening 511. Thus, the processing of the substrate W in the heat treatment apparatus 100 is completed.

<4. effect>
The heat treatment apparatus 100 according to the above embodiment includes first and second light irradiation units 3 that perform light treatment (preheating treatment and flash heating treatment) on the substrate W by irradiating light toward the entire substrate W. 4, a third light irradiation unit 6 that adjusts the surface temperature of the substrate W by irradiating light toward the local region of the substrate W is provided. Therefore, even when a non-uniform region of the temperature distribution occurs in the substrate W during the heat treatment, the non-uniform temperature distribution is eliminated by locally heating the substrate W using the third light irradiation unit 6. be able to. Thereby, the in-plane uniformity of the temperature distribution on the substrate W during the heat treatment can be improved.

  Further, in the heat treatment apparatus 100, an adjustment lamp 61 is disposed on the chamber side portion 51. That is, the adjustment lamp 61 is disposed on a different surface from both the arrangement plane of the halogen lamp 31 provided in the first light irradiation unit 3 and the arrangement plane of the flash lamp 41 provided in the second light irradiation unit 4. Therefore, the adjustment lamp 61 is hardly affected by the halogen lamp 31 and the flash lamp 41.

  In particular, by disposing the adjustment lamp 61 on the upper side of the chamber side portion 51 (that is, the flash lamp 41 side), the thermal influence that the adjustment lamp 61 receives from the halogen lamp 31 can be reduced. In other words, the halogen lamp 31 heats the substrate W by continuously lighting the flash lamp 41 that heats the substrate W with a flash of light for a certain period of time. When the temperature of the adjustment lamp 61 becomes high, the adjustment lamp 61 can be prevented from being heated due to the thermal influence from the halogen lamp 31 by disposing the adjustment lamp 61 on the upper side of the chamber side portion 51.

  Further, since the heat treatment apparatus 100 includes the irradiation direction changing mechanism 62 that changes the light irradiation direction of the adjustment lamp 61, the light emission direction from the adjustment lamp 61 can be arbitrarily adjusted. Furthermore, since the irradiation area size changing mechanism 63 that changes the size of the adjustment light irradiation area S by changing the spread angle of the light beam emitted from the adjustment lamp 61 is provided, the size of the adjustment light irradiation area S can be arbitrarily set. Can be adjusted. Therefore, the light emitted from the adjustment lamp 61 can be reliably incident on the cold spot C region formed on the substrate W in the heat treatment. Thereby, the cold spot C can be surely eliminated (or the occurrence thereof can be prevented), and the in-plane uniformity of the temperature distribution on the substrate W during the heat treatment can be greatly improved.

<5. Other Embodiments>
<5-1. Laser light source>
In the heat treatment apparatus 100 according to the above embodiment, the adjustment lamp 61 is constituted by a halogen lamp, but may be constituted by various other light sources (for example, laser light sources). When a laser light source is used as the adjustment lamp 61, it is possible to irradiate while scanning a local region on the substrate W with a laser beam spot that is narrowed down. For this purpose, the irradiation direction changing mechanism 62 may be constituted by various laser scanning mechanisms.

  For example, as shown in FIG. 4, in the heat treatment, a temperature non-uniform region (here, in particular, a cold spot C) may be formed in a specific region on the substrate W (for example, along the periphery of the substrate W). When it becomes clear, the irradiation position control unit 911 controls the irradiation direction changing mechanism 62 to scan the area with the laser light emitted from the adjustment lamp 61. The laser beam scanning region (that is, the adjustment light irradiation region S) is heated by the light energy, whereby the cold spot C disappears (or is prevented from occurring).

  According to this configuration, since the adjustment light irradiation region S having an arbitrary shape can be formed, for example, the annular cold spot C formed along the peripheral region of the substrate W can be surely eliminated. it can.

<5-2. An adjustment lamp 61 is provided on the first light irradiation unit 3 side>
In the heat treatment apparatus 100 according to the above embodiment, the adjustment lamp 61 provided in the third light irradiation unit 6 is provided in the chamber side portion 51 between the holding unit 2 and the second light irradiation unit 4. However, as shown in FIG. 5, it may be provided on the chamber side 51 between the holding part 2 and the first light irradiation part 3 (third light irradiation part 6a, adjustment lamp 61a). ). However, FIG. 5 is a side sectional view showing the configuration of the heat treatment apparatus 100a according to this modification.

<5-3. An adjustment lamp 61 is provided on the same plane as the light irradiation units 3 and 4>
In the heat treatment apparatus 100 according to the above embodiment, the adjustment lamp 61 is provided on the chamber side 51. However, as shown in FIG. 6, the adjustment lamp 61 is provided on the plane where the flash lamp 41 is provided. (The 3rd light irradiation part 6b, the lamp | ramp 61b for adjustment) may be sufficient. However, FIG. 6 is a side sectional view showing a configuration of a heat treatment apparatus 100b according to this modification.

  Moreover, as shown in FIG. 7, FIG. 8, you may provide on the plane in which the halogen lamp 31 was arrange | positioned (3rd light irradiation part 6c, the lamp | ramp 61c for adjustment). However, FIG. 7 is a side sectional view showing the configuration of the heat treatment apparatus 100c according to this modification. FIG. 8 is a longitudinal sectional view of the heat treatment apparatus 100c as seen from the direction of the arrow Q3 in FIG.

  When the adjustment lamp 61 is provided on a plane on which the halogen lamp 31 or the flash lamp 41 is provided, the adjustment lamp 61 is a lamp provided on the same plane (hereinafter referred to as “adjacent lamp”). It is desirable to use different types of light sources. If a light source of a different type from the adjacent lamp is used as the adjusting lamp 61, the heating pattern by the adjusting lamp 61 will be different from that of the adjacent lamp. Therefore, the uneven temperature distribution caused by the heat treatment by the adjacent lamp is effectively eliminated. can do.

  For example, as shown in FIG. 7, when the adjustment lamp 61 is provided on a plane on which the halogen lamp 31 is disposed (that is, when the adjacent lamp is the halogen lamp 31), the adjustment lamp 61 is not a halogen lamp. It is desirable to use a type of light source (eg, a laser light source).

  Further, when the adjustment lamp 61 is provided on the plane where the halogen lamp 31 or the flash lamp 41 is provided, it is desirable to use a light source having a shape (light emission shape) different from that of the adjacent lamp as the adjustment lamp 61. If a light source having a light emission shape different from that of the adjacent lamp is used as the adjustment lamp 61, the heating pattern by the adjustment lamp 61 is different from that of the adjacent lamp. Can be resolved.

  For example, as shown in FIG. 7, when the adjustment lamp 61 is provided on a plane where the rod-shaped halogen lamp 31 is disposed (that is, when the shape of the adjacent lamp is rod-shaped), as shown in FIG. It is desirable to use a light source (for example, a point light source) other than a rod shape as the adjustment lamp 61.

  That is, when the adjustment lamp 61 is provided on the plane on which the halogen lamp 31 or the flash lamp 41 is provided, a heat source is used as the adjustment lamp 61 by using a light source that is different in at least one of type and light emission shape from the adjacent lamp. It is possible to effectively eliminate the non-uniform temperature distribution that occurs in

<5-4. Others>
In the heat treatment apparatus 100 according to the above embodiment, the single third light irradiation unit 6 is provided. However, a plurality of third light irradiation units 6 may be provided. For example, the third light irradiation unit 6 (see FIG. 1) having the adjustment lamp 61 provided in the chamber side portion 51 and the third light irradiation unit 6b (see FIG. 1) having the adjustment lamp 61b provided in the chamber lid portion 52 (see FIG. 1). It is good also as a structure provided with both.

  In the heat treatment apparatus 100 according to the above-described embodiment, the third light irradiation unit 6 is configured to include one adjustment lamp 61, but may be configured to include a plurality of adjustment lamps 61. In this case, the posture of each of the plurality of adjustment lamps 61 and the divergence angle of the light beam may be defined independently or may be defined uniformly. Further, each of the plurality of adjustment lamps 61 may be disposed at a position adjacent to each other, or may be disposed at a predetermined distance (for example, at a position facing each other on the same horizontal plane).

  In the above embodiment, the posture and the spread angle of the adjustment lamp 61 are changed by the irradiation direction changing mechanism 62 and the irradiation region size changing mechanism 63 that are electrically controlled by the control unit 91. The mechanism for changing the posture and divergence angle of the adjustment lamp 61 is not necessarily limited to electrical control. For example, an axis (lamp support shaft) that is connected to the emission port of the adjustment lamp 61 and defines the position of the emission port is formed through the chamber 5. Similarly, an axis (lens support axis) that defines the position of the lens 631 relative to the adjustment lamp 61 is formed through the chamber 5. The position of the lamp support shaft and the lens support shaft may be adjusted directly by the operator from the outside of the chamber 5 to adjust the posture and the spread angle of the adjustment lamp 61. According to this configuration, the operator changes the position of the various support shafts from the outside of the chamber 5, thereby adjusting the posture and the spread angle of the adjustment lamp 61 (and thus the adjustment light irradiation region S formed on the substrate W). Position and size) can be adjusted as desired.

  In the above-described embodiment, after the preliminary heating process is completed, a process for adjusting the surface temperature of the substrate W by performing a local heating process on the substrate W (step S3 in FIG. 3) is performed. However, the process of step S3 is not necessarily performed after the preheating process, and can be performed at an arbitrary timing from when the substrate W is loaded into the heat treatment apparatus 100 to when it is unloaded. For example, a process for adjusting the surface temperature may be started simultaneously with the preliminary heating process (step S2 in FIG. 3) and after the flash heating process (step S4 in FIG. 3).

  In the above embodiment, the chamber 5 is a hexagonal column. However, the shape of the chamber 5 is not limited to this, and various columnar shapes (for example, a cylinder, a square column, a triangular column, etc.) may be used. May be.

  In the above-described embodiment, both of the two light irradiation units 3 and 4 are arranged at positions separated by 100 mm or more from the substrate W held by the holding unit 2. The portions 3 and 4 need not be separated from the substrate W by 100 mm or more. In the heat treatment apparatus having a configuration in which at least one of the light irradiation sections 3 and 4 is separated by 100 mm or more, the above-described invention works effectively. This is because it becomes difficult to uniformly heat the substrate W as the distance between the substrate W, which is the object to be heated, and the light irradiation unit increases. In addition, an increase in the distance means that the above-mentioned separation distance H (see FIG. 1) can be set large, thereby enabling the present invention to function effectively.

  In the above embodiment, the second light irradiation unit 4 is configured to include the xenon flash lamp as the light source, but a halogen lamp may be used as the light source.

  In the above-described embodiment, each of the first light irradiation unit 3 and the second light irradiation unit 4 includes a plurality of rod-shaped light sources (halogen lamp 31 and flash lamp 41). It does not have to be rod-shaped. For example, a spiral light source may be used. A plurality of point light sources may be arranged regularly. A plurality of annular light sources having different diameters may be arranged concentrically.

  Further, in the above embodiment, the holding unit 2 is configured to support the substrate W by the ring-shaped member, but the mode of holding the substrate W is not limited to this. For example, the substrate W may be supported (surface supported) by a flat plate member (for example, a stage formed of quartz). Moreover, it is good also as a structure which further provides a some support pin in such a plate-shaped member, and supports the board | substrate W by these some support pins (point support). Moreover, it is good also as a structure supported by the hand of various shapes.

It is a sectional side view which shows the structure of the heat processing apparatus. It is a longitudinal cross-sectional view which shows the structure of the heat processing apparatus. It is a figure which shows the flow of the process performed with the heat processing apparatus. It is a longitudinal cross-sectional view which shows the structure of the heat processing apparatus. It is a sectional side view which shows the structure of the heat processing apparatus which concerns on a modification. It is a sectional side view which shows the structure of the heat processing apparatus which concerns on a modification. It is a sectional side view which shows the structure of the heat processing apparatus which concerns on a modification. It is a longitudinal cross-sectional view which shows the structure of the heat processing apparatus which concerns on a modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reflector 2 Holding | maintenance part 3 1st light irradiation part 4 2nd light irradiation part 5 Chamber 6 3rd light irradiation part 61 Adjustment lamp 62 Irradiation direction change mechanism 63 Irradiation area size change mechanism 91 Control part 631 Lens 632 Lens position change Unit 100 heat treatment apparatus 911 irradiation position control unit 912 irradiation region control unit W substrate

Claims (13)

A heat treatment apparatus that heats the substrate by irradiating the substrate with light,
A column-shaped housing;
A holding means for holding the substrate in a posture parallel to the bottom surface of the pillar inside the housing;
One or more light irradiating means each irradiating light toward the substrate from a position separated from the substrate held by the holding means by a predetermined distance;
With
The one or more light irradiation means;
One or more processing light irradiating means each irradiating light from a predetermined plane parallel to the bottom surface of the column body toward the entire substrate;
One or more adjustment light irradiating means each irradiating light from a predetermined position on the side surface of the pillar toward the local region of the substrate;
A heat treatment apparatus comprising: A heat treatment apparatus that heats the substrate by irradiating the substrate with light,
A column-shaped housing;
A holding means for holding the substrate in a posture parallel to the bottom surface of the pillar inside the housing;
One or more light irradiating means each irradiating light toward the substrate from a position separated from the substrate held by the holding means by a predetermined distance;
With
The one or more light irradiation means;
One or more processing light irradiating means each irradiating light from a predetermined plane parallel to the bottom surface of the column body toward the entire substrate;
One or more adjustment light irradiating means each irradiating light toward the local region of the substrate from the same plane as the predetermined processing light irradiating means of the one or more processing light irradiating means;
A heat treatment apparatus comprising: The heat treatment apparatus according to claim 2,
Each of the one or more adjustment light irradiating means comprises:
A light source of a different type from the light source provided in the predetermined processing light irradiation means,
A heat treatment apparatus comprising: The heat treatment apparatus according to claim 2 or 3,
Each of the one or more adjustment light irradiating means comprises:
A light source having a light emission shape different from the light emission shape of the light source provided in the predetermined processing light irradiation means,
A heat treatment apparatus comprising: The heat treatment apparatus according to any one of claims 1 to 4,
An irradiation direction changing means for changing a light irradiation direction of a predetermined adjustment light irradiation means among the one or more adjustment light irradiation means;
A heat treatment apparatus comprising: The heat treatment apparatus according to claim 5,
When a low temperature region occurs in a part of the substrate in the heating process of the substrate by the one or more processing light irradiation units, the irradiation direction changing unit is controlled so that the predetermined adjustment light irradiation unit has the low temperature region. Irradiation position control means for irradiating light toward
A heat treatment apparatus comprising: The heat treatment apparatus according to any one of claims 1 to 6,
By changing the divergence angle of the light beam emitted from the predetermined adjustment light irradiation unit among the one or more adjustment light irradiation units, the light beam emitted from the predetermined adjustment light irradiation unit is placed on the substrate. Irradiation area size changing means for changing the size of the adjustment light irradiation area that is the incident area,
A heat treatment apparatus comprising: The heat treatment apparatus according to claim 7,
The irradiation area size changing means,
An adjustment lens disposed in a posture in which an optical axis coincides with the light irradiation direction of the predetermined adjustment light irradiation means;
An adjustment lens position changing unit that changes a separation distance between the predetermined adjustment light irradiation unit and the adjustment lens by moving the adjustment lens along the optical axis;
A heat treatment apparatus comprising: The heat treatment apparatus according to claim 7 or 8,
When a low temperature region occurs in a part of the substrate in the heating process of the substrate by the one or more processing light irradiation means, the irradiation region size changing unit is controlled so that the adjustment light irradiation region corresponds to the low temperature region. Irradiation area control means for changing the spread angle so as to have a different size,
A heat treatment apparatus comprising: A heat treatment apparatus according to any one of claims 1 to 9,
Among the one or more adjustment light irradiation means, a predetermined adjustment light irradiation means is
Halogen lamp,
A heat treatment apparatus comprising: A heat treatment apparatus according to any one of claims 1 to 9,
Among the one or more adjustment light irradiation means, a predetermined adjustment light irradiation means is
Laser light source,
A heat treatment apparatus comprising: The heat treatment apparatus according to any one of claims 1 to 11,
Among the one or more processing light irradiation means, a predetermined processing light irradiation means is
A flash lamp that emits a flash of light,
A heat treatment apparatus comprising: The heat treatment apparatus according to any one of claims 1 to 12,
Among the one or more processing light irradiation means, a predetermined processing light irradiation means is
Halogen lamp,
A heat treatment apparatus comprising:

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