JP4236881B2 - Heat treatment equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heat treatment apparatus for heat treating a substrate by irradiating a semiconductor wafer, a glass substrate or the like (hereinafter simply referred to as “substrate”) with flash light.
[0002]
[Prior art]
Conventionally, in an ion activation process of a semiconductor wafer after ion implantation, a heat treatment apparatus such as a lamp annealing apparatus using a halogen lamp has been used. In such a heat treatment apparatus, the semiconductor wafer is ion-activated by heating (annealing) the semiconductor wafer 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.
[0003]
However, even when ion activation of a semiconductor wafer is performed using a heat treatment apparatus that raises the temperature of the substrate at a speed of several hundred degrees per second, the profile of ions implanted into the semiconductor wafer is reduced, that is, due to heat It has been found that a phenomenon occurs in which ions diffuse. When such a phenomenon occurs, even if ions are implanted at a high concentration on the surface of the semiconductor wafer, the ions after implantation are diffused, so that ions must be implanted more than necessary. Has occurred.
[0004]
In order to solve the above-mentioned problems, the surface of the semiconductor wafer is irradiated with flash light using a xenon flash lamp or the like, so that only the surface of the semiconductor wafer into which ions are implanted is raised in a very short time (several milliseconds or less). Techniques for warming have been proposed. If the temperature is raised for a very short time with a xenon flash lamp, there is not enough time for ions to diffuse, so only ion activation is performed without the profile of the ions implanted in the semiconductor wafer being distorted. Can do it.
[0005]
[Problems to be solved by the invention]
Also in the heat treatment apparatus using such a xenon flash lamp, it is necessary to change the process conditions in order to obtain the optimum conditions in the process, as in the conventional lamp annealing apparatus. In the case of a heat treatment apparatus using light irradiation, one of the most important process conditions is irradiation intensity. In the case of a lamp annealing apparatus using a conventional halogen lamp, the irradiation intensity can be adjusted relatively easily by controlling the power supplied to the lamp.
[0006]
However, in the case of a heat treatment apparatus using a xenon flash lamp, there are various disadvantages in the method of adjusting the irradiation intensity by changing the main discharge voltage applied to the lamp. Specifically, when the main discharge voltage applied to the xenon flash lamp is changed, the light emission amount-time waveform is changed, and the spectrum distribution is also changed due to the change of the discharge voltage. In other words, simply changing the main discharge voltage applied to the lamp will change not only the irradiation intensity but also the optical characteristics of the flash. As a result, the correlation between the irradiation intensity and the wafer temperature collapses, making temperature control extremely difficult. It was.
[0007]
Further, there is a problem that the deterioration characteristics of the lamp also change when the main discharge voltage applied to the xenon flash lamp is changed.
[0008]
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 easily adjusting the irradiation intensity even in a heat treatment apparatus using a flash lamp.
[0009]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, a first aspect of the present invention is a heat treatment apparatus for heating a substrate by irradiating flash light on the substrate, holding a light source having a plurality of flash lamps, the substrate, and the substrate. A holding means having an assist heating mechanism for performing preliminary heating, an adjusting means for adjusting an irradiation distance between the light source and the holding means for holding the substrate when the flash light is emitted from the light source, and the light source A table holding means for holding a correlation table that associates the irradiation intensity of the substrate surface with the irradiation distance when the flash light is irradiated from the irradiation distance, and the irradiation distance corresponding to the irradiation intensity predetermined for the adjustment means Is obtained from the correlation table, and the distance between the holding means holding the substrate and the light source is set to be the irradiation distance .
[0010]
According to a second aspect of the present invention, in the heat treatment apparatus according to the first aspect of the invention, the adjustment means adjusts the position of the holding means holding the substrate.
[0011]
According to a third aspect of the present invention, in the heat treatment apparatus according to the first aspect of the invention, the adjustment means adjusts the position of the light source.
[0012]
According to a fourth aspect of the present invention, in the heat treatment apparatus according to any one of the first to third aspects of the present invention, the heat treatment apparatus further includes an input unit that receives an input of an irradiation distance correction amount, and the adjustment unit holds the substrate. The distance between the holding means and the light source is set to a distance obtained by adding the correction amount input from the input means to the irradiation distance obtained from the correlation table .
[0013]
According to a fifth aspect of the present invention, in the heat treatment apparatus according to any one of the first to fourth aspects of the present invention, the assist heating mechanism preheats the substrate to 200 ° C. to 600 ° C., and the plurality of flashes. The surface temperature of the substrate is raised to 1000 ° C. to 1100 ° C. with a lighting time of 0.1 to 10 milliseconds .
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0015]
<1. First Embodiment>
1 and 2 are side sectional views showing a first embodiment of a heat treatment apparatus according to the present invention. This heat treatment apparatus is an apparatus for performing heat treatment of a substrate such as a semiconductor wafer by flash light from a xenon flash lamp.
[0016]
This heat treatment apparatus includes a light transmitting plate 61, a bottom plate 62, and a pair of side plates 63 and 64, and includes a chamber 65 for housing the semiconductor wafer W and heat-treating it. The translucent plate 61 constituting the upper part of the chamber 65 is made of, for example, a material having infrared transparency such as quartz, and functions as a chamber window that transmits light emitted from the light source 5 and guides it into the chamber 65. is doing. The bottom plate 62 constituting the chamber 65 is provided with support pins 70 that pass through a heat diffusion plate 73 and a heating plate 74 described later to support the semiconductor wafer W from its lower surface.
[0017]
Further, an opening 66 for carrying in and out the semiconductor wafer W is formed in the side plate 64 constituting the chamber 65. The opening 66 can be opened and closed by a gate valve 68 that rotates about a shaft 67. The semiconductor wafer W is loaded into the chamber 65 by a transfer robot (not shown) with the opening 66 opened . Further, when the semiconductor wafer W is heat-treated in the chamber 65, the opening 66 is closed by the gate valve 68.
[0018]
The chamber 65 is provided below the light source 5. The light source 5 includes a plurality (27 in the present embodiment) of xenon flash lamps 69 (hereinafter also simply referred to as “flash lamps 69”) and a reflector 71. The plurality of flash lamps 69 are rod-shaped lamps each having a long cylindrical shape, and are arranged in parallel with each other such that the longitudinal direction thereof is along the horizontal direction. The reflector 71 is disposed above the plurality of flash lamps 69 so as to cover them entirely.
[0019]
The xenon flash lamp 69 includes a glass tube in which xenon gas is sealed and an anode and a cathode connected to a capacitor at both ends thereof, and a trigger electrode wound around an external portion 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 the xenon flash lamp 69, 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.
[0020]
A light diffusing plate 72 is disposed between the light source 5 and the translucent plate 61. As the light diffusion plate 72, a surface of quartz glass as an infrared transmitting material subjected to light diffusion processing is used.
[0021]
Part of the light emitted from the flash lamp 69 passes directly through the light diffusing plate 72 and the light transmitting plate 61 toward the chamber 65. Further, another part of the light emitted from the flash lamp 69 is once reflected by the reflector 71, then passes through the light diffusing plate 72 and the light transmitting plate 61 and goes into the chamber 65.
[0022]
A heating plate 74 and a heat diffusion plate 73 are provided in the chamber 65. The heat diffusion plate 73 is attached to the upper surface of the heating plate 74. Further, a position shift prevention pin 75 of the semiconductor wafer W is attached to the surface of the heat diffusion plate 73.
[0023]
The heating plate 74 is for preheating (assist heating) the semiconductor wafer W. The heating plate 74 is made of aluminum nitride and has a configuration in which a heater and a sensor for controlling the heater are housed. On the other hand, the heat diffusing plate 73 diffuses the heat energy from the heating plate 74 and uniformly preheats the semiconductor wafer W. As the material of the heat diffusion plate 73, a material having a relatively low thermal conductivity such as sapphire (Al ₂ O ₃ : aluminum oxide) or quartz is employed.
[0024]
The heat diffusing plate 73 and the heating plate 74 are configured to move up and down between the loading / unloading position of the semiconductor wafer W shown in FIG. 1 and the heat treatment position of the semiconductor wafer W shown in FIG. .
[0025]
That is, the heating plate 74 is connected to the moving plate 42 via the cylindrical body 41. The moving plate 42 can be moved up and down by being guided by a guide member 43 supported by a bottom plate 62 of the chamber 65. A fixed plate 44 is fixed to the lower end portion of the guide member 43, and a motor 40 that rotationally drives a ball screw 45 is disposed at the central portion of the fixed plate 44. The ball screw 45 is screwed with a nut 48 connected to the moving plate 42 via connecting members 46 and 47. Therefore, the heat diffusion plate 73 and the heating plate 74 can be moved up and down between the loading / unloading position of the semiconductor wafer W shown in FIG. 1 and the heat treatment position of the semiconductor wafer W shown in FIG. it can.
[0026]
The loading / unloading position of the semiconductor wafer W shown in FIG. 1 is placed on the support pin 70 by placing the semiconductor wafer W loaded from the opening 66 using a transfer robot (not shown). This is the position where the heat diffusion plate 73 and the heating plate 74 are lowered so that the completed semiconductor wafer W can be carried out from the opening 66. In this state, the upper end of the support pin 70 passes through the through holes formed in the heat diffusion plate 73 and the heating plate 74 and protrudes upward from the surface of the heat diffusion plate 73.
[0027]
On the other hand, the heat treatment position of the semiconductor wafer W shown in FIG. 2 is a position where the heat diffusion plate 73 and the heating plate 74 are raised above the upper ends of the support pins 70 in order to perform heat treatment on the semiconductor wafer W. In the process in which the heat diffusion plate 73 and the heating plate 74 are raised from the loading / unloading position of FIG. 1 to the heat treatment position of FIG. 2, the semiconductor wafer W placed on the support pins 70 is received by the heat diffusion plate 73 and its lower surface. Is supported by the surface of the heat diffusing plate 73, and is held in a horizontal posture at a position in the chamber 65 close to the translucent plate 61. Conversely, in the process in which the heat diffusion plate 73 and the heating plate 74 are lowered from the heat treatment position to the carry-in / carry-out position, the semiconductor wafer W supported by the heat diffusion plate 73 is transferred to the support pins 70.
[0028]
In a state where the thermal diffusion plate 73 and the heating plate 74 that support the semiconductor wafer W are raised to the heat treatment position, the translucent plate 61 is located between the semiconductor wafer W held by them and the light source 5. Note that the distance between the heat diffusion plate 73 and the light source 5 at this time can be adjusted to an arbitrary value by controlling the rotation amount of the motor 40. Further, it will be described later.
[0029]
Further, between the bottom plate 62 of the chamber 65 and the moving plate 42, a telescopic bellows 77 is disposed so as to surround the cylindrical body 41 and maintain the chamber 65 in an airtight body. When the heat diffusing plate 73 and the heating plate 74 are raised to the heat treatment position, the bellows 77 contracts, and when the heat diffusion plate 73 and the heating plate 74 are lowered to the loading / unloading position, the bellows 77 is expanded and the atmosphere in the chamber 65 is increased. Shut off from outside atmosphere.
[0030]
In the side plate 63 opposite to the opening 66 in the chamber 65, an introduction path 78 connected to the on-off valve 80 is formed. The introduction path 78 is for introducing a gas necessary for processing, for example, an inert nitrogen gas, into the chamber 65. On the other hand, a discharge passage 79 connected to the on-off valve 81 is formed in the opening 66 in the side plate 64. The discharge path 79 is for discharging the gas in the chamber 65, and is connected to an exhaust means (not shown) via the on-off valve 81.
[0031]
The heat treatment apparatus includes a controller 10 for controlling each mechanism unit such as the motor 40. FIG. 3 is a block diagram showing the configuration of the controller 10. The configuration of the controller 10 as hardware is the same as that of a general computer. That is, the controller 10 stores a CPU 11 that performs various arithmetic processes, a ROM 12 that is a read-only memory that stores basic programs, a RAM 13 that is a readable / writable memory that stores various information, control software, data, and the like. A magnetic disk 14 is connected to a bus line 19.
[0032]
The bus line 19 is electrically connected to a motor 40 and a sensor 25 of a heat treatment apparatus. The sensor 25 is a distance measuring unit that measures the distance between the heat diffusion plate 73 and the flash lamp 69. In the first embodiment, for example, an encoder that detects the amount of rotation of the motor 40 is employed. The CPU 11 of the controller 10 can control the motor 40 based on the detection result of the sensor 25 so that the distance between the heat diffusing plate 73 and the heating plate 74 and the light source 5 becomes a predetermined value.
[0033]
Further, a display unit 21 and an input unit 22 are electrically connected to the bus line 19. The display unit 21 is configured using, for example, a liquid crystal display or the like, and displays various information such as processing results and recipe contents. The input unit 22 is configured using, for example, a keyboard, a mouse, and the like, and receives input of commands, parameters, and the like. The operator of the apparatus can input commands and parameters from the input unit 22 while confirming the contents displayed on the display unit 21. Note that the display unit 21 and the input unit 22 may be integrated to form a touch panel.
[0034]
Next, the heat treatment operation of the semiconductor wafer W by the heat treatment apparatus according to the present invention will be described. A semiconductor wafer W to be processed in this heat treatment apparatus is a semiconductor wafer after ion implantation.
[0035]
In this heat treatment apparatus, in a state where the heat diffusing plate 73 and the heating plate 74 are arranged at the loading / unloading positions of the semiconductor wafer W shown in FIG. It is carried in and placed on the support pin 70. When the loading of the semiconductor wafer W is completed, the opening 66 is closed by the gate valve 68. Thereafter, the heat diffusion plate 73 and the heating plate 74 are raised to the heat treatment position of the semiconductor wafer W shown in FIG. 2 by driving the motor 40 to hold the semiconductor wafer W in a horizontal posture.
[0036]
At this time, the CPU 11 of the controller 10 adjusts the distance between the heat diffusion plate 73 and the heating plate 74 holding the semiconductor wafer W and the light source 5 so that a predetermined irradiation intensity can be obtained. Specifically, it is performed as follows. First, the correlation between the irradiation intensity on the surface of the semiconductor wafer W and the irradiation distance when the flash light is irradiated from the light source 5 is obtained in advance by experiment or simulation. The irradiation distance is a distance between the light source 5 and the heat diffusion plate 73 and the heating plate 74 that hold the semiconductor wafer W when the flash light is irradiated from the light source 5. A correlation table is created by experimentally determining the correlation between the irradiation distance and the irradiation intensity of the surface of the semiconductor wafer W (the semiconductor wafer W held by the thermal diffusion plate 73 and the heating plate 74).
[0037]
FIG. 4 is a diagram illustrating an example of a correlation table representing the correlation between the irradiation intensity on the surface of the semiconductor wafer W and the irradiation distance. As the irradiation distance increases, the irradiation intensity on the surface of the semiconductor wafer W decreases.
[0038]
The correlation table as shown in FIG. 4 is stored in the magnetic disk 14 as a lookup table LUT (FIG. 3). The CPU 11 obtains an irradiation distance corresponding to a predetermined irradiation intensity with reference to the lookup table LUT, and the distance between the heat diffusion plate 73 and the heating plate 74 holding the semiconductor wafer W and the light source 5 is determined. The motor 40 is controlled so as to be the irradiation distance. The “predetermined irradiation intensity” may be described in a recipe for the semiconductor wafer W to be processed, or may be input from the input unit 22 by the operator of the apparatus each time processing is performed. For example, if the operator inputs the irradiation intensity required for processing as L1, the CPU 11 obtains an irradiation distance H1 corresponding to the irradiation intensity L1 from the lookup table LUT, and the heat diffusion plate 73 and the heating plate holding the semiconductor wafer W. The motor 40 is controlled so that the distance between the light source 74 and the light source 5 becomes the irradiation distance H1.
[0039]
When the semiconductor wafer W is raised to the heat treatment position in this way, the on-off valve 80 and the on-off valve 81 are opened to form a nitrogen gas flow in the chamber 65. Further, the heat diffusion plate 73 and the heating plate 74 are preheated to a predetermined temperature by the action of a heater built in the heating plate 74. For this reason, in a state where the heat diffusion plate 73 and the heating plate 74 are raised to the heat treatment position of the semiconductor wafer W, the semiconductor wafer W is preheated by contacting the heat diffusion plate 73 in a heated state, and the semiconductor wafer W The temperature gradually increases.
[0040]
In this state, the semiconductor wafer W is continuously heated by the heat diffusion plate 73. When the temperature of the semiconductor wafer W rises, a temperature sensor (not shown) always monitors whether or not the surface temperature of the semiconductor wafer W has reached the preheating temperature T1.
[0041]
The preheating temperature T1 is, for example, about 200 ° C. to 600 ° C. Even if the semiconductor wafer W is heated to such a preheating temperature T1, ions implanted into the semiconductor wafer W will not diffuse.
[0042]
Eventually, when the surface temperature of the semiconductor wafer W reaches the preheating temperature T1, the flash lamp 69 is turned on to perform flash heating. The lighting time of the flash lamp 69 in this flash heating process is a time of about 0.1 to 10 milliseconds. Thus, in the flash lamp 69, the electrostatic energy stored in advance is converted into such an extremely short light pulse, so that an extremely strong flash light is irradiated.
[0043]
By such flash heating, the irradiation intensity on the surface of the semiconductor wafer W instantaneously becomes L1, and the surface temperature instantaneously reaches the temperature T2. This temperature T2 is a temperature necessary for the ion activation treatment of the semiconductor wafer W at about 1000 ° C. to 1100 ° C. When the surface of the semiconductor wafer W is heated to such a processing temperature T2, ions implanted into the semiconductor wafer W are activated. Therefore, the irradiation intensity L1 at which the temperature T2 necessary for ion activation can be obtained can be input from the input unit 22 or set in a recipe.
[0044]
During flash heating, the surface temperature of the semiconductor wafer W is raised to the processing temperature T2 in an extremely short time of about 0.1 to 10 milliseconds, so that the ion activation in the semiconductor wafer W is completed in a short time. To do. Therefore, the ions implanted into the semiconductor wafer W do not diffuse, and it is possible to prevent the phenomenon that the profile of the ions implanted into the semiconductor wafer W is lost. Since the time required for ion activation is extremely short compared with the time required for ion diffusion, the ion activation is performed even for a short time in which no diffusion of about 0.1 millisecond to 10 millisecond occurs. Complete.
[0045]
Further, before the flash lamp 69 is turned on to heat the semiconductor wafer W, the surface temperature of the semiconductor wafer W is heated to the preheating temperature T1 of about 200 ° C. to 600 ° C. using the heating plate 74. The flash lamp 69 makes it possible to quickly raise the temperature of the semiconductor wafer W to the processing temperature T2 of about 1000 ° C. to 1100 ° C.
[0046]
Further, since the heating plate 74 is raised together with the semiconductor wafer W, the preliminary heating is performed without any problem regardless of the adjustment of the irradiation distance.
[0047]
After the flash heating process is completed, the heat diffusion plate 73 and the heating plate 74 are lowered to the loading / unloading position of the semiconductor wafer W shown in FIG. There are opened. Then, the semiconductor wafer W placed on the support pins 70 is carried out by a transfer robot (not shown). As described above, a series of heat treatment operations is completed.
[0048]
In such a heat treatment apparatus, when it is desired to change the processing temperature, that is, to change the irradiation intensity, a new irradiation intensity is input from the input unit 22. For example, when it is desired to set the irradiation intensity of the semiconductor wafer W set to the irradiation intensity L1 in the recipe to L2, the operator inputs a new irradiation intensity L2 from the input unit 22. Then, the CPU 11 obtains an irradiation distance H2 corresponding to the new irradiation intensity L2 from the look-up table LUT, and the distance between the heat diffusion plate 73 and the heating plate 74 holding the semiconductor wafer W and the light source 5 is determined from the irradiation distance H1. The motor 40 is controlled so that the irradiation distance is H2. In this way, the irradiation distance between the heat diffusion plate 73 and the heating plate 74 holding the semiconductor wafer W when the flash light is irradiated from the light source 5 and the light source 5 is adjusted, that is, changed.
[0049]
Further, the correlation itself between the irradiation intensity on the surface of the semiconductor wafer W and the irradiation distance may change due to deterioration of the flash lamp 69 or the like. In such a case, after the irradiation distance is adjusted according to the lookup table LUT, the operator inputs the irradiation distance correction amount from the input unit 22. For example, when the flash lamp 69 is deteriorated and the illuminance is reduced, a correction amount that shortens the irradiation distance is input. Then, the CPU 11 causes the distance between the heat diffusion plate 73 and the heating plate 74 holding the semiconductor wafer W and the light source 5 to be a distance obtained by adding the correction amount to the irradiation distance obtained from the lookup table LUT. The motor 40 is controlled. In this way, the irradiation distance is adjusted, i.e., corrected, to compensate for changes in the apparatus state such as deterioration of the flash lamp 69.
[0050]
In this way, the irradiation intensity can be adjusted by adjusting the irradiation distance while keeping the main discharge voltage applied to the flash lamp 69 constant, so that the optical characteristics of the light emitted from the flash lamp 69 can be adjusted. Irradiation intensity can be easily adjusted without making the difference.
[0051]
<2. Second Embodiment>
Next, a second embodiment of the present invention will be described. In the first embodiment described above, the irradiation distance is adjusted by adjusting the positions of the thermal diffusion plate 73 and the heating plate 74 holding the semiconductor wafer W. However, in the second embodiment, the light source 5 is adjusted. The irradiation distance is adjusted by adjusting the position. FIG. 5 is a side sectional view showing a second embodiment of the heat treatment apparatus according to the present invention. In addition, about the member similar to the heat processing apparatus of 1st Embodiment mentioned above, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.
[0052]
In the heat treatment apparatus of the second embodiment, the casing 51 that houses the flash lamp 69 and the reflector 71 is configured to move up and down under the driving of a ball screw 53 that is rotated by a pair of motors 52. The distance between the heat diffusing plate 73 and the heating plate 74 and the light source 5 can be adjusted to an arbitrary value by controlling the rotation amount of the motor 52.
[0053]
The sensor 55 is distance measuring means for measuring the distance between the heat diffusing plate 73 and the flash lamp 69. In the second embodiment, an encoder that detects the rotation amount of the motor 52 is employed. The motor 52 and the sensor 55 are electrically connected to the bus line 19 of the controller 10. Thus, the CPU 11 of the controller 10 can control the motor 52 based on the detection result of the sensor 55 so that the distances between the heat diffusion plate 73 and the heating plate 74 and the light source 5 become a predetermined value.
[0054]
The heat treatment operation of the semiconductor wafer W by the heat treatment apparatus of the second embodiment is the same as that of the first embodiment. Then, the CPU 11 of the controller 10 controls the motor 52 to adjust the distance between the heat diffusion plate 73 and the heating plate 74 holding the semiconductor wafer W and the light source 5 so as to obtain a predetermined irradiation intensity. . Further, the case where it is desired to change the irradiation intensity and the case where the correction amount is input are the same as those in the first embodiment.
[0055]
In the second embodiment, as in the first embodiment, the irradiation intensity can be adjusted by adjusting the irradiation distance while keeping the main discharge voltage applied to the flash lamp 69 constant. Irradiation intensity can be easily adjusted without changing the optical characteristics of the light irradiated from.
[0056]
<3. Modification>
While the embodiments of the present invention have been described above, the present invention is not limited to the above examples. For example, in each of the above embodiments, the heat diffusion plate 73 and the heating plate 74 are moved up and down by the motor 40 or the light source 5 is moved up and down by the motor 52. However, the heat diffusion plate 73, the heating plate 74, and the light source 5 It is good also as a structure which raises / lowers both simultaneously. In other words, any configuration may be used as long as the distance between the holding means for holding the semiconductor wafer W and the light source is relatively adjusted.
[0057]
Further, instead of employing encoders as the sensors 25 and 55, an optical sensor that directly measures the distance between the heat diffusion plate 73 and the light source 5 may be employed.
[0058]
In each of the above embodiments, the semiconductor wafer is irradiated with light to perform the ion activation process. However, the substrate to be processed by the heat treatment apparatus according to the present invention is not limited to the semiconductor wafer. Absent. For example, the glass substrate on which various silicon films such as a silicon nitride film and a polycrystalline silicon film are formed may be processed by the heat treatment apparatus according to the present invention. As an example, an amorphous silicon film made amorphous by ion implantation of silicon into a polycrystalline silicon film formed on a glass substrate by a CVD method is formed, and a silicon oxide film serving as an antireflection film is further formed thereon. Form. In this state, the entire surface of the amorphous silicon film is irradiated with light by the heat treatment apparatus according to the present invention, so that a polycrystalline silicon film obtained by polycrystallizing the amorphous silicon film can be formed.
[0059]
Further, a heat treatment according to the present invention is applied to a TFT substrate having a structure in which a base silicon oxide film and a polysilicon film obtained by crystallizing amorphous silicon are formed on a glass substrate, and the polysilicon film is doped with impurities such as phosphorus and boron. It is also possible to activate the impurities implanted in the doping process by irradiating light with an apparatus.
[0060]
【The invention's effect】
As described above, according to the first to fifth aspects of the present invention, the flash lamp is used to adjust the irradiation distance between the holding means for holding the substrate and the light source when the flash light is emitted from the light source. The irradiation intensity can be adjusted by adjusting the irradiation distance while keeping the discharge voltage applied to the electrode constant, and the irradiation intensity can be easily adjusted even in a heat treatment apparatus using a flash lamp. In addition, the irradiation distance corresponding to the predetermined irradiation intensity is obtained from the correlation table, and the distance between the holding means holding the substrate and the light source is the irradiation distance. The irradiation intensity can be adjusted by adjusting.
[0061]
According to the invention of claim 2, since the position of the holding means holding the substrate is adjusted, the irradiation distance can be easily adjusted.
[0062]
According to the invention of claim 3, since the position of the light source is adjusted, the irradiation distance can be easily adjusted.
[0064]
According to the invention of claim 4 , the distance between the holding means holding the substrate and the light source is set to a distance obtained by adding the correction amount inputted from the input means to the irradiation distance obtained from the correlation table. Therefore, the irradiation distance can be adjusted to compensate for changes in the apparatus state.
[Brief description of the drawings]
FIG. 1 is a side sectional view showing a first embodiment of a heat treatment apparatus according to the present invention.
FIG. 2 is a side sectional view showing a first embodiment of a heat treatment apparatus according to the present invention.
FIG. 3 is a block diagram illustrating a configuration of a controller.
FIG. 4 is a diagram showing an example of a correlation table representing a correlation between irradiation intensity on the surface of a semiconductor wafer and irradiation distance.
FIG. 5 is a side sectional view showing a second embodiment of the heat treatment apparatus according to the present invention.
[Explanation of symbols]
5 Light source 10 Controller 11 CPU
14 Magnetic disk 21 Display unit 22 Input unit 25, 55 Sensor 61 Translucent plate 40, 52 Motor 65 Chamber 69 Flash lamp 71 Reflector 73 Heat diffusion plate 74 Heating plate LUT Look-up table W Semiconductor wafer

Claims (5)

A heat treatment apparatus for heating a substrate by irradiating a flash with the substrate,
A light source having a plurality of flash lamps;
Holding means comprising an assist heating mechanism for holding the substrate and preheating the substrate;
An adjusting means for adjusting an irradiation distance between the light source and the holding means that holds the substrate when the flash light is emitted from the light source;
Table holding means for holding a correlation table in which the irradiation intensity of the substrate surface when the flash light is irradiated from the light source and the irradiation distance are associated with each other;
Equipped with a,
The adjusting unit obtains an irradiation distance corresponding to a predetermined irradiation intensity from the correlation table, and a distance between the holding unit holding the substrate and the light source becomes the irradiation distance. Heat treatment equipment. The heat treatment apparatus according to claim 1, wherein
The heat treatment apparatus characterized in that the adjustment means adjusts the position of the holding means holding the substrate. The heat treatment apparatus according to claim 1, wherein
The said adjustment means adjusts the position of the said light source, The heat processing apparatus characterized by the above-mentioned. In the heat processing apparatus in any one of Claims 1-3,
An input means for receiving an input of an irradiation distance correction amount;
The adjustment unit is configured such that the distance between the holding unit holding the substrate and the light source is a distance obtained by adding the correction amount input from the input unit to the irradiation distance obtained from the correlation table. A heat treatment apparatus characterized by In the heat processing apparatus in any one of Claims 1-4 ,
The assist heating mechanism preheats the substrate to 200 ° C. to 600 ° C.,
The plurality of flash lamps raises the surface temperature of the substrate to 1000 ° C. to 1100 ° C. with a lighting time of 0.1 to 10 milliseconds .

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