JP2006080294A - Substrate manufacturing method - Google Patents

Abstract

An object of the present invention is to provide a method for manufacturing a substrate capable of preventing the occurrence of slip dislocation defects when the substrate is subjected to heat treatment.
A loading step of loading a substrate into a reaction furnace, a heating step of raising the substrate temperature to a processing temperature, a heat treatment step of heat-treating the substrate at the processing temperature, and the substrate temperature from the processing temperature. It has a temperature lowering process for lowering the temperature to a temperature lower than the processing temperature and an unloading process for unloading the substrate from the reaction furnace 34, and at least two or more lowering processes for decreasing the substrate temperature during the temperature lowering process. Provided.
[Selection] Figure 4

Description

  The present invention relates to a method for manufacturing a semiconductor wafer or a glass substrate.

  For example, when a substrate such as a plurality of silicon single crystal wafers is heat-treated using a vertical heat treatment furnace, a substrate support (boat) made of silicon carbide or the like is used. The substrate support is provided with support grooves for supporting the substrate at, for example, three points.

  In this case, when the heat treatment is performed at a temperature of about 1000 ° C. or higher, slip dislocation defects are generated in the substrate in the vicinity of the support groove, which causes a slip line. When a slip line occurs, the flatness of the substrate decreases. For this reason, in the lithography process, which is one of the important processes in the LSI manufacturing process, mask misalignment (mask misalignment due to defocusing or deformation) occurs, and there is a problem that it is difficult to manufacture an LSI having a desired pattern. Was.

  As means for solving such a problem, there is known one that prevents the generation of crystal defects during high-temperature heat treatment of a silicon wafer by slowing the temperature raising / lowering rate as the processing temperature increases (for example, Patent Documents). 1).

JP-A-8-45946

  As described above, the method of slowing the temperature raising / lowering speed has a problem that the effect is not sufficient and slipping occurs depending on the case.

  An object of the present invention is to provide a substrate manufacturing method capable of preventing the occurrence of slip dislocation defects when heat treatment is performed on the substrate.

  In order to solve the above-described problems, the present invention is characterized by a carrying-in process for carrying a substrate into a processing chamber, a temperature raising process for raising the substrate temperature to a processing temperature, and a heat treatment process for heat-treating the substrate at the processing temperature. And a substrate manufacturing method comprising: a temperature lowering step for lowering the substrate temperature from the processing temperature to a temperature lower than the processing temperature; and a carry-out step for unloading the substrate from the processing chamber. The method of manufacturing a substrate has a lowering step of lowering at least twice.

  Preferably, the descending step is performed in a temperature range of 800 ° C. or higher and 1050 ° C. or lower, and further 900 ° C. or higher and 1000 ° C. or lower. Preferably, the descent start temperature and descent end temperature, or descent start temperature or descent end temperature are the same in the first descent process and the second and subsequent descent processes. Preferably, the temperature drop widths of the first descent process and the second and subsequent descent processes are the same. Preferably, the second and subsequent descent steps are made to have a lower temperature drop rate than the first descent step. Preferably, the second and subsequent lowering steps are made smaller in temperature drop width than the first lowering step. Preferably, the support is made of a silicon holder or ring thicker than the substrate, or a SiC holder or ring. Furthermore, the heat treatment in the present invention is preferably performed at a high temperature of 1200 ° C. or higher, more preferably 1350 ° C. or higher.

  According to the present invention, a high-quality substrate can be manufactured without causing slip in the high-temperature heat treatment.

Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a heat treatment apparatus 10 according to an embodiment of the present invention. The heat treatment apparatus 10 is, for example, a vertical type and includes a housing 12 in which a main part is arranged. A pod stage 14 is connected to the housing 12, and the pod 16 is conveyed to the pod stage 14. The pod 16 stores, for example, 25 substrates, and is set on the pod stage 14 with a lid (not shown) closed.

  In the case 12, a pod transfer device 18 is disposed at a position facing the pod stage 14. Further, a pod shelf 20, a pod opener 22, and a substrate number detection 24 are arranged in the vicinity of the pod transfer device 18. The pod carrying device 18 carries the pod 16 among the pod stage 14, the pod shelf 20, and the pod opener 22. The pod opener 22 opens the lid of the pod 16, and the number of substrates in the pod 16 with the lid opened is detected by the substrate number detector 24.

  Further, a substrate transfer device 26, a notch aligner 28, and a substrate support 30 (board) are disposed in the housing 12. The substrate transfer machine 26 includes an arm 32 that can take out, for example, five substrates. By moving the arm 32, the pod placed at the position of the pod opener 22, the notch aligner 28, and the substrate support 30. Transfer the substrate between. The notch aligner 28 detects notches or orientation flats formed on the substrate and aligns the notches or orientation flats of the substrate at a certain position.

  In FIG. 2, a reactor 34 is shown. The reaction furnace 34 has a reaction tube 36 made of SiC. The reaction tube 36 is formed in a cylindrical shape with the upper part sealed, and the lower part is formed in a flange shape. A quartz adapter 38 is disposed below the reaction tube 36, and the reaction tube 36 is supported by the adapter 38. A heater 40 is disposed around the reaction tube 36 excluding the adapter 38. The substrate support 30 described above is inserted into the reaction tube 36. The lower part of the reaction tube 36 is opened to insert the substrate support 30, and this open part is between the furnace port seal cap 42 and the substrate support 30, a first cap 44 made of quartz, and this A SiC second cap 46 disposed above the first cap 44 is interposed. The substrate support 30 supports a large number of substrates 48 in a substantially horizontal state with a plurality of steps with gaps, and is loaded into the reaction tube 36.

  In order to enable processing at a high temperature of 1200 ° C. or higher, the reaction tube 36 is made of SiC. If this SiC reaction tube 36 is extended to the furnace port and sealed with SiC, the temperature of the seal will be increased by SiC and the O-ring, which is the sealing material, may be melted. If the seal part of the reaction tube 42 made of SiC is cooled so as not to melt the O-ring, the reaction tube 36 made of SiC is damaged due to a difference in thermal expansion due to a temperature difference. Therefore, the heating area by the heater 40 is made of SiC, and the quartz adapter 38 is provided in a portion outside the heating area by the heater 40, so that the furnace port portion can be sealed. Further, if the seal between the reaction tube 36 made of SiC and the adapter 38 made of quartz is improved in both surface accuracy, a temperature difference occurs because the reaction tube 36 made of SiC is arranged in the heating region of the heater 40. Without thermal expansion. Therefore, the flange portion of the SiC reaction tube 36 can be kept flat, and there is no gap between the adapter 38 and the sealing performance can be ensured by simply placing the SiC reaction tube 36 on the quartz adapter 38. can do.

  The adapter 38 is formed with a gas supply port 50 and a gas exhaust port 52 integrally with the adapter 38. A gas introduction pipe 54 is connected to the gas supply port 50, and an exhaust pipe 56 is connected to the gas exhaust port 52.

  A gas introduction path extending in the vertical direction is provided inside the adapter 38, and a nozzle mounting hole 58 is formed at an upper portion thereof so as to open upward. The nozzle mounting hole 58 is connected to the gas supply port 50 via a gas introduction path. A nozzle 60 is inserted and fixed in the nozzle mounting hole 58. That is, the nozzle 60 is connected to the upper surface of the adapter 38. With this configuration, the nozzle connection portion is not easily deformed by heat and is not easily destroyed. Further, there is a merit that the nozzle 60 and the adapter 38 can be easily assembled and disassembled. The gas introduced from the gas introduction pipe 54 into the gas supply port 50 is supplied into the reaction pipe 36 through the nozzle 60.

The nozzle 60 is configured to extend along the inner wall of the reaction tube 36 to above the substrate arrangement region (above the substrate support 30). The nozzle 60 has an inner diameter of 10 mm and a length of 100 mm, for example.
In this embodiment, the number of nozzles 60 is one. However, the number of nozzles 60 is not limited to this, and a plurality of nozzles 60 may be provided, and at least one nozzle may be provided.

Next, the substrate support 30 will be described.
In FIG. 3, the substrate support 30 includes a main body portion 62 and a support portion 64 provided on the main body portion 62. The main body 62 is made of, for example, silicon carbide (SiC), silicon (Si) (single crystal or polycrystal), or quartz (SiO 2). For example, three or four columns 66 are formed with a number of claw portions 68 at equal intervals in the vertical direction of the columns 66. The claw portion 68 extends horizontally toward the inside of the substrate support 30, and the support portion 64 is placed and supported on the claw portion 68.

  The support part 64 is made of, for example, silicon or SiC. For example, it is composed of a plate-like member thicker than the thickness of the substrate, for example, a member formed in a disk shape, and the substrate 48 is placed in contact with the support portion 64. In this embodiment, the support portion 64 is formed in a disc shape, but may be a plate shape, a ring shape, or a disc shape having other shapes, and one or a plurality of grooves or holes. May be formed.

Next, the operation of the heat treatment apparatus 10 configured as described above will be described.
First, when a pod 16 containing a plurality of substrates is set on the pod stage 14, the pod 16 is transferred from the pod stage 14 to the pod shelf 20 by the pod transfer device 18 and stocked on the pod shelf 20. Next, the pod 16 is transferred from the pod stage 14 to the pod shelf 20 by the pod transfer device 18 and stocked on the pod shelf 20. Next, the pod 16 stocked on the pod shelf 20 is transported and set to the pod opener 22 by the pod transport device 18, the lid of the pod 16 is opened by the pod opener 22, and the pod 16 is detected by the substrate number detector 24. The number of substrates accommodated in the sensor is detected.

  Next, the substrate is transferred from the pod 16 at the position of the pod opener 22 by the substrate transfer machine 26 and transferred to the notch aligner 28. The notch aligner 28 detects notches while rotating the substrates, and aligns the notches of the plurality of substrates at the same position based on the detected information. Next, the substrate is transferred from the notch aligner 28 by the substrate transfer device 26 and transferred to the substrate support 30.

  Thus, when one batch of substrates is transferred to the substrate support 30, the substrate support 30 loaded with a plurality of substrates is loaded into the reaction furnace 34 set at a temperature of, for example, about 600 ° C. Then, the inside of the reaction tube 36 is sealed with a furnace port seal cap 42. Next, the furnace temperature is raised to the heat treatment temperature, and the processing gas is introduced into the reaction tube 36 from the gas introduction tube 54 through the gas supply port 50 and the nozzle 60. The processing gas includes nitrogen, argon, hydrogen, oxygen, and the like. When heat-treating the substrate, the substrate is heated to a temperature of about 1000 ° C. or more, for example. During this time, the substrate is heat-treated according to a preset temperature raising sequence and heat treatment sequence while monitoring the temperature in the reaction tube 36 with a thermocouple (not shown). The temperature rise sequence and the heat treatment sequence are controlled by a control means (controller) (not shown).

  When the heat treatment of the substrate is completed, for example, after the temperature in the furnace is lowered to a temperature of about 600 ° C., the substrate support 30 is unloaded from the reaction furnace 34, and all the substrates supported by the substrate support 30 are cooled. The substrate support 30 is put on standby at a predetermined position. Even when the temperature in the furnace is lowered, the temperature is lowered according to a preset temperature lowering sequence while monitoring the temperature in the reaction tube 36 with a thermocouple (not shown). The temperature lowering sequence is controlled by a control means (controller) (not shown). Next, when the substrate of the substrate support 30 that has been put on standby is cooled to a predetermined temperature, the substrate transfer device 26 takes out the substrate from the substrate support 30 and puts it into the empty pod 16 set in the pod opener 22. Transport and store. Next, the pod carrying device 18 carries the pod 16 containing the substrate to the pod shelf 20 and further to the pod stage 14 to complete.

  In the present embodiment, the wafer is heat-treated by a sequence provided with a step of lowering the temperature at least twice during the temperature raising sequence. This sequence is controlled by a control means (controller) (not shown).

  4 to 7 show first to fourth temperature sequence examples in the present embodiment. In any temperature sequence example, a substrate support in which a plurality of substrates are loaded in a plurality of stages with gaps in a substantially horizontal state is loaded into a reaction furnace set at a temperature of 600 ° C., and then the furnace The internal temperature is raised to a heat treatment temperature of about 1200 ° C. (temperature raising step), and when the substrate temperature reaches the processing temperature, the processing gas is introduced to heat-treat the substrate (heat treatment step). After the heat treatment, the temperature is lowered to a temperature of about 600 ° C. (temperature lowering process), and then the substrate support is unloaded from the reaction furnace. Hereinafter, these temperature sequence examples will be described in detail.

FIG. 4 shows a first temperature sequence example in the present embodiment. In the case of this sequence example, two or more lowering steps for lowering the substrate temperature are provided in the middle of the temperature raising step for raising the substrate temperature to the processing temperature so that the first and second and subsequent temperature drop widths are the same. I have to. In the case of FIG. 4, the lowering process for lowering the substrate temperature is provided twice in the vicinity of 1000.degree. Specifically, when a temperature near 1000 ° C. is reached, a lowering process for lowering the substrate temperature is provided to lower the temperature to near 900 ° C. (first lowering process). When the temperature again reaches around 1000 ° C., the temperature is lowered again to around 900 ° C. (second descending step). In the example of FIG. 4, the descent start temperature in the descent process is about 1000 ° C. for both the first and second times, and the descent end temperature is about 900 ° C. for both the first and second times. That is, the temperature drop width in the lowering process is the same for the first time and the second time. Thus, the lowering process for lowering the substrate temperature is provided at least twice in the middle of the temperature raising process, and the temperature drop width is the same between the first time and the second time.
With such a temperature sequence, the in-plane temperature distribution of the wafer can be changed in the middle of the temperature raising process, and thereby the shape (deformation method) of the wafer can be changed. For this reason, the contact part of a wafer and a support part changes every moment according to a temperature change, and welding with a wafer and a support part can be prevented. When the temperature rises, welding occurs at several points between the wafer and the support part, but when the temperature drop by the descent process begins, the shape of the wafer is automatically deformed, and the fusion point between the wafer and the support part at an early stage. Is released and the stress is released. That is, it is possible to prevent an increase in stress at the wafer support point between the wafer and the support part, and it is possible to prevent dislocation and occurrence of a slip line following this dislocation. At this time, since the stress may not be sufficiently released by only one descent process (the fusion point cannot be sufficiently separated), the descent process is preferably performed a plurality of times, that is, at least twice.

FIG. 5 shows a second temperature sequence example in the present embodiment. In the case of this sequence example, a lowering step for lowering the substrate temperature is provided twice or more in the middle of the temperature raising step for raising the substrate temperature to the processing temperature, and the temperature drop width after the second time is made smaller than the first time. . In the case of FIG. 5, a lowering process for lowering the substrate temperature is provided twice in the vicinity of 1000.degree. Specifically, when the temperature reaches around 1000 ° C., a lowering process for lowering the substrate temperature is provided to lower the temperature to around 800 ° C. (first lowering process). When the temperature reaches around 1000 ° C. again, the temperature is lowered to around 950 ° C. (second descending step). In the example of FIG. 5, the descent start temperature in the descent process is around 1000 ° C. for both the first and second times. However, the lowering end temperature is around 800 ° C. for the first time and around 950 ° C. for the second time. That is, the temperature drop width in the lowering process is smaller in the second time than in the first time. Thus, the lowering process for lowering the substrate temperature is provided twice or more in the middle of the temperature raising process, and the temperature drop width is smaller than the first time from the second time.
With such a temperature sequence, the in-plane temperature distribution of the wafer can be changed in the middle of the temperature raising process, and thereby the shape (deformation method) of the wafer can be changed. For this reason, the contact part of a wafer and a support part changes every moment according to a temperature change, and welding with a wafer and a support part can be prevented. When the temperature rises, welding occurs at several points between the wafer and the support part, but when the temperature drop by the descent process begins, the shape of the wafer is automatically deformed, and the fusion point between the wafer and the support part at an early stage. Is released and the stress is released. That is, it is possible to prevent an increase in stress at the wafer support point between the wafer and the support part, and it is possible to prevent dislocation and occurrence of a slip line following this dislocation. At this time, since the stress may not be sufficiently released by only one descent process (the fusion point cannot be sufficiently separated), the descent process is preferably performed a plurality of times, that is, at least twice. Further, if the temperature drop width in the lowering process is made different between the first time and the second time and later, the manner (degree) of change of the in-plane temperature distribution of the wafer can be changed between the first time and the second time and later. This makes it possible to change the shape (deformation method) of the wafer between the first time and the second and subsequent times. Thus, by changing the shape of the wafer (how to deform), it is possible to easily release the stress at the contact point between the wafer and the support portion.

FIG. 6 shows a third temperature sequence example in the present embodiment. In the case of this sequence example, a lowering step for lowering the substrate temperature is provided twice or more in the middle of the temperature raising step for raising the substrate temperature to the processing temperature, and the temperature drop rate for the second and subsequent times is made smaller than the first time. . In the case of FIG. 6, the lowering process for lowering the substrate temperature is provided twice in the vicinity of 1000.degree. Specifically, when a temperature near 1000 ° C. is reached, a lowering process for lowering the substrate temperature is provided to lower the temperature to near 900 ° C. (first lowering process). When the temperature reaches around 1000 ° C. again, the temperature is lowered to around 900 ° C. (second descending step). At this time, the temperature lowering rate in the second lowering process is made smaller than the temperature lowering rate in the first lowering process. That is, the temperature lowers more slowly in the second descent process than in the first descent process. As described above, the lowering process for lowering the substrate temperature is provided twice or more in the middle of the temperature raising process, and the temperature lowering rate is made smaller from the first time to the second time.
With such a temperature sequence, the in-plane temperature distribution of the wafer can be changed in the middle of the temperature raising process, and thereby the shape (deformation method) of the wafer can be changed. For this reason, the contact part of a wafer and a support part changes every moment according to a temperature change, and welding with a wafer and a support part can be prevented. When the temperature rises, welding occurs at several points between the wafer and the support part, but when the temperature drop by the descent process begins, the shape of the wafer is automatically deformed, and the fusion point between the wafer and the support part at an early stage. Is released and the stress is released. That is, it is possible to prevent an increase in stress at the wafer support point between the wafer and the support part, and it is possible to prevent dislocation and occurrence of a slip line following this dislocation. At this time, since the stress may not be sufficiently released by only one descent process (the fusion point cannot be sufficiently separated), the descent process is preferably performed a plurality of times, that is, at least twice. Further, if the temperature drop rate in the lowering process is made different between the first time and the second time and later, the manner (degree) of change of the in-plane temperature distribution of the wafer can be changed between the first time and the second time and later. This makes it possible to change the shape (deformation method) of the wafer between the first time and the second and subsequent times. Thus, by changing the shape of the wafer (how to deform), it is possible to easily release the stress at the contact point between the wafer and the support portion.

FIG. 7 shows a fourth temperature sequence example in the present embodiment. In the case of this sequence example, two or more lowering steps for lowering the substrate temperature are provided in the middle of the temperature raising step for raising the substrate temperature to the processing temperature so that the first and second and subsequent temperature drop widths are the same. I have to. In the case of FIG. 7, a lowering process for lowering the substrate temperature is provided three times around 1000.degree. Specifically, when a temperature near 1000 ° C. is reached, a lowering process for lowering the substrate temperature is provided to lower the temperature to near 900 ° C. (first lowering process). When the temperature again reaches around 1000 ° C., the temperature is lowered again to around 900 ° C. (second descending step). When the temperature reaches around 1000 ° C. again, the temperature is lowered again to around 900 ° C. (third descending step). In the example of FIG. 7, the descent start temperature in the descent process is about 1000 ° C. for the first, second, and third times, and the descent end temperatures are about 900 ° C. for the first, second, and third times. That is, the temperature drop width in the descent process is the same for the first, second and third times. Thus, the lowering process for lowering the substrate temperature is provided at least twice in the middle of the temperature raising process, and the temperature drop width is the same between the first time and the second time.
With such a temperature sequence, the in-plane temperature distribution of the wafer can be changed in the middle of the temperature raising process, and thereby the shape (deformation method) of the wafer can be changed. For this reason, the contact part of a wafer and a support part changes every moment according to a temperature change, and welding with a wafer and a support part can be prevented. When the temperature rises, welding occurs at several points between the wafer and the support part, but when the temperature drop by the descent process starts, the shape of the wafer is automatically deformed, and the fusion point between the wafer and the support part at an early stage. Is released and the stress is released. That is, it is possible to prevent an increase in stress at the wafer support point between the wafer and the support part, and it is possible to prevent dislocation and occurrence of a slip line following this dislocation. At this time, since the stress may not be sufficiently released by only one descent process (the fusion point cannot be sufficiently separated), the descent process is preferably performed a plurality of times, that is, at least twice.

  In the middle of the temperature raising process described above, a temperature lowering step for lowering the substrate temperature is provided at least twice or more, and the first and second and subsequent temperature drop widths are made the same. The process of reducing the temperature drop rate for the second and subsequent times from the first time may be performed independently, or may be performed by combining any of the processes selected from these processes. Also good. Moreover, you may make it perform any process selected from these processes at short intervals, so that temperature becomes high. In addition, the descent process performed in the middle of the temperature raising process described above can be performed in a short time because it has good thermal response if performed in a high temperature region, but if the descent process is performed at a very high temperature, the descent process itself may cause slip. It is possible to become. Considering this, the descending step is preferably performed in a temperature range of 800 ° C. or higher and 1050 ° C. or lower, and further 900 ° C. or higher and 1000 ° C. or lower.

  In the heat treatment step described above, the substrate may be heat-treated with a silicon plate-like member thicker than the substrate, or the substrate may be heat-treated with a SiC holder supported. Alternatively, the substrate may be heat-treated in a state where the substrate is supported by four or more support portions including the substrate center or five or more support portions.

  When heat treatment is performed in a state where the substrate is supported by a silicon plate-like member (supporting portion) thicker than the substrate, the silicon plate-like member is formed in a cylindrical shape concentrically with the substrate, for example, on the upper surface of the substrate. The lower surface contacts and supports the substrate. In addition, the shape of a plate-shaped member does not need to be a column shape, and can also be comprised as an elliptical column or a polygonal column.

  The diameter of the plate-like member is smaller than the diameter of the substrate, that is, the upper surface of the plate-like member has an area smaller than the area of the flat surface, which is the lower surface of the substrate, and the substrate leaves the periphery of the substrate. It is supported by the member. The substrate has a diameter of, for example, 300 mm, and therefore the diameter of the plate-like member is less than 300 mm, and is preferably about 100 mm to 250 mm (about 1/3 to 5/6 of the substrate outer diameter).

  Further, the thickness of the plate-like member in the cylinder axis direction is formed to be thicker than the thickness of the substrate. The thickness of the substrate is, for example, 700 μm. Therefore, the thickness of the plate-like member is over 700 μm and can be up to 10 mm, and at least twice the thickness of the substrate, for example, 3 mm to 10 mm is preferable. Further, 3 to 6 mm is preferable, and 4 to 5 mm is more preferable. Since the thickness of the plate-like member is such a thickness, the rigidity of the plate-like member can be increased, and the plate-like member with respect to temperature changes at the time of board loading, temperature rise, temperature drop, heat treatment, board carry-out, etc. The deformation of the member can be suppressed. Thereby, it is possible to prevent the occurrence of substrate slip due to deformation of the plate-like member.

  Moreover, since the material of the plate member is made of silicon, which is the same material as the substrate, that is, a material having the same thermal expansion coefficient and hardness as the silicon substrate, the thermal expansion of the substrate and the plate member with respect to temperature change, The difference in thermal shrinkage can be eliminated, and even if a stress is generated at the contact point between the substrate and the plate-like member, the stress is easily released, so that the substrate is hardly damaged. Thereby, it is possible to prevent the occurrence of slip to the substrate due to the difference in thermal expansion coefficient and the difference in hardness between the substrate and the plate-like member. In the above description, the case where the diameter (area) of the plate-like member is smaller than the substrate has been described, but the plate-like member diameter can be made larger than the substrate diameter. In this case, in order to ensure the rigidity of the plate member, it is necessary to further increase the thickness of the plate member.

  In the description of the above embodiment and examples, a batch-type apparatus for heat-treating a plurality of substrates was used as the heat treatment apparatus, but the present invention is not limited to this, and a single-wafer type is used. Good.

  The heat treatment apparatus according to the present invention can also be applied to a substrate manufacturing process.

  An example in which the heat treatment apparatus of the present invention is applied to one step of a manufacturing process of a SIMOX (Separation by Implanted Oxygen) wafer which is a kind of SOI (Silicon On Insulator) wafer will be described.

  First, oxygen ions are implanted into the single crystal silicon wafer by an ion implantation apparatus or the like. Thereafter, the wafer into which oxygen ions are implanted is annealed at a high temperature of 1300 ° C. to 1400 ° C., for example, 1350 ° C. or higher, for example, in an Ar, O 2 atmosphere using the heat treatment apparatus of the above embodiment. By these processes, a SIMOX wafer in which the SiO 2 layer is formed inside the wafer (the SiO 2 layer is embedded) is manufactured.

  In addition to the SIMOX wafer, it is also possible to apply the heat treatment apparatus of the present invention to one step of the manufacturing process of the hydrogen anneal wafer. In this case, the wafer is annealed at a high temperature of about 1200 ° C. or higher in a hydrogen atmosphere using the heat treatment apparatus of the present invention. As a result, crystal defects in the wafer surface layer where an IC (integrated circuit) is made can be reduced, and the safety of the crystal can be improved.

  In addition, the heat treatment apparatus of the present invention can be applied to one step of the epitaxial wafer manufacturing process.

  Even in the case where the high-temperature annealing process performed as one step of the substrate manufacturing process as described above is performed, the occurrence of the substrate slip can be prevented by using the heat treatment method according to the present invention.

The heat treatment apparatus according to the present invention can also be applied to a semiconductor device manufacturing process.
In particular, a heat treatment process performed at a relatively high temperature, for example, a thermal oxidation process such as wet oxidation, dry oxidation, hydrogen combustion oxidation (pyrogenic oxidation), HCl oxidation, boron (B), phosphorus (P), arsenic (As ), An antimony (Sb) or other impurity (dopant) is preferably applied to a thermal diffusion process for diffusing the semiconductor thin film.

  Even in the case of performing heat treatment as one step of the manufacturing process of such a semiconductor device, the occurrence of slip can be prevented by using the heat treatment apparatus according to the present invention.

As described above, the present invention is characterized by the matters described in the claims, and further includes the following embodiments.
A processing chamber for processing a substrate, a support for supporting the substrate in the processing chamber, a heater for heating the substrate in the processing chamber, and a substrate temperature lowered at least twice while the substrate temperature is raised to the processing temperature. A heat treatment apparatus having control means for controlling a heater.

It is a perspective view which shows the heat processing apparatus which concerns on embodiment of this invention. It is sectional drawing which shows the reaction furnace used for the heat processing apparatus which concerns on embodiment of this invention. It is sectional drawing which shows the board | substrate support body used for the heat processing apparatus which concerns on embodiment of this invention. It is a figure which shows the 1st temperature sequence example which concerns on embodiment of this invention. It is a figure which shows the 2nd temperature sequence example which concerns on embodiment of this invention. It is a figure which shows the 3rd temperature sequence example which concerns on embodiment of this invention. It is a figure which shows the 4th example of a temperature sequence which concerns on embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Heat processing apparatus 30 Substrate support body 40 Reactor 46 Heater

Claims (1)

A loading step of loading the substrate into the processing chamber;
A temperature raising step for raising the substrate temperature to the processing temperature;
A heat treatment step of heat treating the substrate at a treatment temperature;
A temperature lowering process for lowering the substrate temperature from the processing temperature to a temperature lower than the processing temperature;
A substrate manufacturing method including an unloading step of unloading the substrate from the processing chamber,
A method for manufacturing a substrate, comprising a descent step of lowering the substrate temperature at least twice during the temperature raising step.

Images