JP2006237625A - Heat treatment device, method for manufacturing semiconductor device and method for manufacturing substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat treatment device, a method for manufacturing a semiconductor device and a method for manufacturing a substrate, in which the high-quality semiconductor device can be manufactured by reducing a slip dislocation defect occurring in the substrate during heat treatment. <P>SOLUTION: The heat treatment device 10 has a reactor 40 which processes the substrate 68, and a substrate support 30 which supports the substrate 68 within the reactor 40. The substrate support 30 has a supporting part 58 which is in contact with the substrate 68 and a mounting part 66 which mounts the supporting part 58, and a fitting groove 74 fitted with the supporting part 58 is formed in the mounting part 66. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a heat treatment apparatus for heat treating a semiconductor wafer, a glass substrate or the like, a method for manufacturing a semiconductor device, and a method for manufacturing a semiconductor wafer or a glass substrate.

  For example, when a substrate such as a plurality of silicon wafers is heat-treated using a vertical heat treatment furnace, a silicon carbide substrate support (boat) 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 more, 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 deteriorates. For these reasons, there is a problem in that it is difficult to manufacture an LSI having a desired pattern due to mask misalignment (focal misalignment or mask misalignment due to deformation) in a lithography process, which is one of important processes in the LSI manufacturing process. It has occurred.

  As means for solving such a problem, a technique is known in which a dummy wafer is first placed in a support groove, and a substrate to be processed is placed on the dummy wafer (see Patent Document 1). This is to change the conventional three-point support to the surface support by the dummy wafer, thereby suppressing the concentration of the self-weight stress of the substrate to be processed, preventing the warpage of the substrate, and preventing the occurrence of slip dislocation defects. It is.

As one of this type of substrate support, it is known to form a CVD-SiC film on a boat base material such as Si-SiC in order to prevent impurity contamination from the base material (patent) Reference 2). According to this known example, the thickness of the CVD-SiC film is 30 μm to 100 μm. That is, if the thickness of the coating is smaller than 30 μm, impurities cannot be diffused from the boat base material to the coating surface, and the purpose of the CVD coating can be prevented. If it exceeds, it will be in the buildup state where CVD concentrates and accumulates on the edge part of a boat base material, and when a boat (substrate support body) is used in this state, it is said that a burr | flash will be formed and it will cause particle contamination.
As another conventional example, a SiC film is formed by CVD on a substrate such as a Si-impregnated sintered SiC material or graphite to improve heat resistance, impact resistance, oxidation resistance, and corrosion resistance. (See Patent Document 3). According to this known example, the thickness of the SiC film is preferably 20 μm to 200 μm. If the thickness is less than 20 μm, the life of the SiC film itself is likely to be consumed, and if it exceeds 200 μm, the SiC film peels off. It will be easier.

Further, as another conventional example, there is known one in which a surface of a SiC jig (boat or the like) is subjected to CVD-SiC coating and an SiO2 film is formed on the surface (see Patent Document 4). According to this known example, the SiC coating is performed to ensure the uniformity of the surface of the substrate, and the thickness of the SiC film is set to 100 μm as an example. In addition, the SiO2 film is formed in order to prevent thinning of the substrate during dry cleaning with ClF3, and the thickness is desirably 100 to 100 [mu] m.
As still another conventional example, it is known that a surface of a Si-SiC support is coated with CVD-SiC by about 100 μm (see Patent Document 5).

JP 2000-223495 A JP 2000-164522 A Japanese Patent Laid-Open No. 2002-249483 Japanese Patent Laid-Open No. 10-242254 Japanese Patent Laid-Open No. 10-321543

  However, according to the experimental results by the present inventors, the above-mentioned conventional example in which the substrate is placed on the dummy wafer is improved as compared with the three-point support, but slip lines are generated and slip dislocation defects occur. It was insufficient in terms of prevention.

  This is because the dummy wafer is as thin as 700 μm, for example, like the substrate, and is deformed by a difference in thermal expansion and other stresses generated with the substrate support made of silicon carbide. This is considered to cause slip dislocation defects.

  In addition, as a result of experiments by the inventors of the present application, depending on the material to be coated on the substrate mounting surface of the support portion of the substrate support and the thickness of the film, slip may occur due to the coefficient of thermal expansion of the film. Found that there is.

  Accordingly, the present invention provides a heat treatment apparatus, a semiconductor device manufacturing method, and a substrate manufacturing method capable of manufacturing a high-quality semiconductor device by reducing the occurrence of slip dislocation defects in the substrate generated during the heat treatment. It is aimed.

In order to solve the above-mentioned problem, the first feature of the present invention includes a reaction furnace for treating a substrate, and a substrate support for supporting the substrate in the reaction furnace. The heat treatment apparatus includes a support portion that comes into contact with the substrate and a placement portion on which the support portion is placed, and the placement portion has a groove in which the support portion is fitted. The thickness of the support portion is larger than the thickness of the substrate, and is preferably 10 mm or less, for example, 3 mm to 6 mm, and more preferably 4 to 5 mm. Further, when the thickness of the support portion is compared with the thickness of the substrate, the thickness of the support portion is preferably at least twice the thickness of the substrate.
The substrate support can be configured as a boat in which a large number of mounting portions extend in parallel from the main body. The main body can be made of, for example, silicon carbide. Moreover, the support part should just be a shape which can mount a board | substrate on one end surface, such as cylindrical shape, elliptical column shape, polygonal column shape. This support part is preferably thicker than the thickness of the mounting part of the main body part.

  The second feature of the present invention is that it has a support portion that comes into contact with the substrate and a placement portion on which the support portion is placed, and the placement portion has a groove into which the support portion is fitted. A step of supporting a substrate by a substrate support configured to be formed; a step of carrying a substrate supported by the substrate support into a reaction furnace; and a substrate supported by the substrate support in the reaction furnace And a step of carrying out the processed substrate supported by the substrate support from the reaction furnace.

  The third feature of the present invention is that it has a support portion that comes into contact with the substrate and a placement portion on which the support portion is placed, and the placement portion has a groove into which the support portion is fitted. A semiconductor having a step of supporting a substrate by a substrate support to be formed, a step of processing a substrate supported by the substrate support, and a step of unloading the processed substrate supported by the substrate support from a reaction furnace Device manufacturing method.

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 casing 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 housing 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 detector 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 machine 26, a notch aligner 28, and a substrate support 30 (boat) are disposed in the housing 12. The substrate transfer machine 26 has 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. Transport substrates 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 40 is shown. The reaction furnace 40 has a reaction tube 42, and the substrate support 30 is inserted into the reaction tube 42. The lower part of the reaction tube 42 is opened to insert the substrate support 30, and this open part is sealed with a seal cap 44. The periphery of the reaction tube 42 is covered with a soaking tube 46, and a heater 48 is disposed around the soaking tube 46. The thermocouple 50 is disposed between the reaction tube 42 and the soaking tube 46 so that the temperature in the reaction furnace 40 can be monitored. The reaction tube 42 is connected to an introduction tube 52 for introducing a processing gas and an exhaust tube 54 for exhausting the processing gas.

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 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.

  In this way, when one batch of substrates is transferred to the substrate support 30, for example, the substrate support 30 loaded with a plurality of substrates is loaded into the reaction furnace 40 set to a temperature of about 700 ° C. Then, the inside of the reaction tube 42 is sealed with the seal cap 44. Next, the furnace temperature is raised to the heat treatment temperature, and the processing gas is introduced from the introduction pipe 52. 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 rise and heat treatment program while monitoring the temperature in the reaction tube 42 with the thermocouple 50.

  When the heat treatment of the substrate is completed, for example, after the temperature in the furnace is lowered to a temperature of about 700 ° C., the substrate support 30 is unloaded from the reaction furnace 40 until all the substrates supported by the substrate support 30 are cooled. Then, 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 drop program while monitoring the temperature in the reaction tube 42 by the thermocouple 50. 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.

Next, the substrate support 30 will be described in detail.
3 to 5, the substrate support 30 is composed of a main body portion 56 and a support portion 58. The main body 56 is made of, for example, silicon carbide, and includes an upper plate 60, a lower plate 62, and a support column 64 that connects the upper plate 60 and the lower plate 62. The main body portion 56 is formed with a plurality of mounting portions 66 extending in parallel from the support column 64 toward the substrate transfer machine 26 described above.

  The support portion 58 is made of a silicon plate-like member, and is formed in, for example, a cylindrical shape concentric with the substrate 68. The lower surface of the support portion 58 contacts the upper surface of the placement portion 66, and the support portion 58 is placed on the placement portion 66. The lower surface of the substrate 68 is brought into contact with the upper surface of the support portion 58 to place and support the substrate 68.

The diameter of the support portion 58 is smaller than the diameter of the substrate 68, that is, the upper surface of the support portion 58 has an area smaller than the area of the flat surface which is the lower surface of the substrate 68, and the substrate 68 has a peripheral edge of the substrate 68. It remains and is supported by the support portion 58. The substrate 68 has a diameter of, for example, 300 mm, and therefore the support portion 58 has a diameter of less than 300 mm, preferably about 100 mm to 250 mm (about 1/3 to 5/6 of the substrate outer diameter).
Note that the diameter (area) of the support portion 58 may be larger than the diameter (area) of the substrate 68. In this case, it is preferable to further increase the thickness of the support portion 58.

Further, the thickness of the support portion 58 in the cylindrical axis direction is formed to be thicker than the thickness of the substrate 68. The thickness of the substrate 68 is, for example, 700 μm. Therefore, the thickness of the support portion 58 exceeds 700 μm and can be up to 10 mm, and at least twice the thickness of the substrate 68, for example, 3 mm to 10 mm. Is preferable, 3 to 6 mm is more preferable, and 4 to 5 mm is more preferable. Further, the thickness of the support portion 58 is greater than the thickness of the placement portion 66. The reason why the thickness of the support portion 58 is set to such a thickness is to increase the rigidity of the support portion 58 itself and to suppress deformation of the support portion 58 during heat treatment.
If the deformation during the heat treatment can be suppressed, the thickness of the support portion 58 made of silicon does not necessarily have to be greater than the thickness of the substrate 68.

  As shown in FIG. 6, a circular fitting groove 74 may be formed in the mounting portion 66 corresponding to the support portion 58, and the support portion 58 may be fitted into the fitting groove 74. The total thickness of the support portion 58 and the placement portion 66 can be reduced while maintaining the thickness of the support portion 58 without reducing the thickness, and the number of substrates 68 processed at one time can be increased. . Further, the position of the support portion 58 can be stabilized by fitting the support portion 58 into the fitting groove 74. In this case, a slight gap may be formed between the support portion 58 and the fitting groove 74 in consideration of thermal expansion.

Further, as shown in FIG. 7, an opening 66 a is provided in the mounting portion 66, and a convex portion 58 a that fits into the opening 66 a is provided on the lower surface of the supporting portion 58, and the convex portion 58 a of the supporting portion 58 is connected to the mounting portion 66. You may make it fit in the opening 66a. In the present invention, such a shape is also included in the plate member. In this case as well, a slight gap may be formed between the convex portion 58a of the support portion 58 and the opening 66a of the placement portion 66 in consideration of thermal expansion.
In addition, the shape of the support part 58 does not need to be a column shape like this embodiment, and can also be comprised as an elliptical column or a polygonal column. Further, the support portion 58 can be fixed to the placement portion 66.

An adhesion preventing layer (coated film) 70 is formed on the upper surface (substrate mounting surface) of the support portion 58 on the substrate 68 side. The adhesion preventing layer 70 is deposited on the silicon surface by, for example, treating the silicon surface or by CVD (plasma CVD or thermal CVD).
silicon nitride (Si ₃ N ₄ ) film, silicon carbide (SiC) film, silicon oxide (SiO ₂ ) film, glassy carbon, microcrystalline diamond, etc. formed by positioning), excellent in heat resistance and wear resistance The support portion 58 after the processing of the substrate 68 and the substrate 68 are prevented from being bonded. When the adhesion preventing layer 70 is a silicon carbide (SiC) film, the thickness of the film is preferably in the range of 0.1 μm to 50 μm. When the silicon carbide film 70 is thickened, due to the difference in thermal expansion coefficient between silicon and silicon carbide, the silicon support part 58 is pulled by the silicon carbide film 70, and the deformation amount of the entire support part increases. This large deformation may cause the substrate 68 to slip. On the other hand, when the thickness of the silicon carbide film 70 is as described above, the amount by which the silicon support portion 58 is pulled by the silicon carbide film 70 is reduced, and the deformation amount of the entire support portion is also reduced. That is, when the silicon carbide film 70 is thinned, the stress due to the difference in thermal expansion coefficient between the support portion 58 and the film 70 is reduced, the deformation amount of the entire support portion is reduced, and the thermal expansion coefficient of the entire support portion is also the original one. It approaches the thermal expansion coefficient of silicon (substantially the same thermal expansion coefficient when the substrate 68 is silicon), and can prevent slipping.

  If the thickness of the silicon carbide film 70 is less than 0.1 μm, the silicon carbide film 70 is too thin and consumed, and it becomes necessary to recoat silicon carbide on the silicon support portion 58, and the same support portion. 58 cannot be used repeatedly. If the thickness of the film 70 is 0.1 μm or more, it is not necessary to recoat the silicon carbide film 70 on the silicon support portion 58 frequently, and the same support portion 58 can be used repeatedly. It is preferable that the thickness of the silicon carbide film 70 is 1 μm or more because the film is not further consumed and the number of times the same support portion 58 can be used repeatedly increases.

  When the thickness of the silicon carbide film 70 exceeds 50 μm, the silicon carbide film 70 itself is easily cracked, and slippage is likely to occur in the substrate due to the crack. If the thickness of the film 70 is 50 μm or less, the film 70 is hardly cracked, and the stress due to the difference in thermal expansion coefficient between the silicon support portion 58 and the silicon carbide film 70 is reduced as described above. Therefore, the deformation of the entire support portion is reduced, and the occurrence of slippage of the substrate can be prevented. When the thickness of the silicon carbide film is 15 μm or less, almost no substrate slip occurs. Further, when the thickness of the silicon carbide film 70 is 0.1 μm to 3 μm, the substrate 68 does not slip. Therefore, the thickness of the silicon carbide film 70 is preferably 0.1 μm to 50 μm, more preferably 0.1 μm to 15 μm, and even more preferably 0.1 μm to 3 μm.

  When the thicknesses of the silicon support portion 58 and the silicon carbide film 70 are expressed as a ratio of both, the thickness of the silicon carbide film 70 is 0.0025% to the thickness of the silicon support portion 58. It should be 1.25%, more preferably 0.0025% to 0.38%, and still more preferably 0.0025% to 0.25%.

The film 70 can be formed by similarly coating silicon nitride (Si ₃ N ₄ ) other than silicon carbide by plasma CVD or thermal CVD. In the case of silicon nitride, the thickness of the film 70 is preferably 0.1 μm to 30 μm, more preferably 0.1 μm to 5 μm.

  Further, a concave portion 72 is formed on the periphery of the upper surface of the support portion 58 by performing smooth chamfering. The recess 72 prevents the substrate 68 from coming into contact with the periphery of the support portion 58 and causing damage to the substrate 68.

  Instead of forming the adhesion preventing layer 70 on the entire surface of the support portion 58, a chip 76 made of these materials is placed on a part of the substrate mounting surface of the support portion 58 as shown in FIG. The substrate 68 may be supported by the chip 76. In this case, it is preferable to provide three or more chips 76.

  Further, as shown in FIG. 9, concentric grooves 78 are formed in the vicinity of the periphery of the support portion 58 to reduce the contact area with the substrate 68, and the probability that the substrate 68 is damaged due to the contact with the support portion 58 is increased. In addition to being able to reduce, it is possible to prevent the substrate 68 from being displaced.

  In the above-described embodiment, since the thickness of the support portion 58 is set to a predetermined thickness that is larger than the thickness of the substrate 68 as described above, the rigidity of the support portion 58 can be increased. It is possible to suppress the deformation of the support portion 58 with respect to a temperature change at the time of temperature reduction, heat treatment, substrate unloading, or the like. Thereby, it is possible to prevent the occurrence of slip to the substrate 68 due to the deformation of the support portion 58. Further, since the material of the support portion 58 is made of silicon, which is the same material as the substrate 68, that is, a material having the same thermal expansion coefficient and hardness as the silicon substrate 68, the substrate 68 and the support portion 58 with respect to temperature change The difference between thermal expansion and thermal contraction can be eliminated, and even if stress is generated at the contact point between the substrate 68 and the support portion 58, the stress is easily released, so that the substrate 68 is less likely to be damaged. . Thereby, it is possible to prevent the occurrence of slip to the substrate 68 due to a difference in thermal expansion coefficient and a difference in hardness between the substrate 68 and the support portion 58.

  In the description of the above embodiment and examples, the case where the diameter (area) of the support portion is smaller than that of the substrate has been described. In this case, it is necessary to further increase the thickness of the support portion 58 in order to ensure the rigidity of the support portion 58.

  Further, since the silicon support portion 58 is coated with the adhesion preventing film 70 such as a silicon carbide film, the heat adhesion between the support portion 58 and the substrate 68 can be prevented. Since the film 70 is thinly formed as described above, the stress due to the difference in thermal expansion coefficient between the support portion 58 and the film 70 can be reduced, and the thermal expansion of the silicon support portion 58 is hindered. In other words, the entire support portion including the film 70 can be maintained substantially equal to the thermal expansion coefficient of the original silicon. The film 70 may also be coated on the back surface or side surface of the support portion 58.

In FIG. 10, various modifications regarding the support portion 58 are shown.
In the above-described embodiment, the film 70 is formed only on the substrate placement surface of the support portion 58. However, as shown in FIG. The film 70 may be formed on the mounting surface), the side surface, and the back surface.
Further, as shown in FIG. 10B, the film 70 can be formed on the front surface (substrate mounting surface) and side surfaces of the support portion 58 except for the back surface of the support portion 58.
The film 70 is not limited to a single layer, and may be formed as a plurality of layers. For example, as shown in FIG. 10C, the second film 82 is formed on the first film 80. be able to. The first film 80 is made of, for example, silicon carbide (SiC), silicon nitride (Si ₃ N ₄ ), polycrystalline silicon (Poly-Si), silicon oxide (SiO ₂ ), glassy carbon, or microcrystalline diamond. In the case of silicon carbide or silicon nitride, as described above, it can be formed by plasma CVD or thermal CVD. The second film 82 can be made of a material having a hardness lower than that of the first film 70 during heat treatment, for example, silicon oxide (SiO ₂ ).
As described above, the second film 82 which is the outermost surface is made of a material whose hardness is smaller than that of the first film 80 during the heat treatment, so that stress is generated at the contact point between the substrate 68 and the support portion 58 during the high temperature heat treatment. In this case, the stress is easily released, so that the substrate 68 is hardly damaged and slipping is hardly generated. In particular, when the outermost film 70 is made of SiO ₂ whose hardness is smaller than that of the substrate (Si) 68 at the time of heat treatment, the higher degree of SiO ₂ breaks and releases the stress at the time of heat treatment, so that the hardness is high. No scratch is generated on the other substrate 68, and no slip is generated. That is, it is more preferable that the outermost surface is made of a material having a hardness lower than that of other films and a hardness lower than that of the substrate during heat treatment.

The outermost SiO ₂ is preferably amorphous. When the temperature of the substrate 68 and the support portion 58 becomes high, the substrate 68 and the support portion 58 are fused at their contact points. At that time, if the contact point of the support portion 58 with the substrate 68 is a crystal, the crystal portion does not flow viscously. The stress due to the difference in expansion cannot be released, and eventually slip occurs in either the substrate 68 or the support portion 58. On the other hand, when the contact point of the support portion 58 with the substrate 68 is amorphous, the amorphous portion flows in a viscous flow (viscous deformation), so even if the substrate 68 and the support portion 58 are fused. The stress generated at the contact point can be released, the substrate 68 is not damaged, and the occurrence of slip can be prevented.

  Further, as shown in FIG. 10 (d), the support portion 58 is notched leaving the peripheral portion of the substrate mounting surface of the support portion 58, and has a notch portion 84 formed in a circle on the center side, and a ring at the periphery. The first film 80 and the second film 82 may be formed on the substrate placement surface and the side surface of the protrusion 86. Thereby, the area which the board | substrate 68 contacts can be decreased.

    The second film 82 can be formed by CVD or the like, similar to the first film 80, but may be formed naturally when the substrate 68 is processed, as will be described later. .

[Example 1]
FIG. 11 shows a first embodiment according to the present invention. Similar to the above-described embodiment, for example, a mounting portion 66 is formed to protrude in parallel from the support column 64 on the substrate support 30 whose main body portion is made of silicon carbide. Note that a plurality of columns, for example, 3 to 4 columns, are provided. The plate (base) 88 is made of, for example, a cylindrical plate-like member made of silicon carbide (SiC), and the lower surface periphery of the plate 88 is supported by the mounting portion 66. The support portion 82 is made of a cylindrical plate-shaped member made of silicon (Si), and is placed on the upper surface of the plate 88. An adhesion preventing layer 70 made of, for example, silicon carbide is formed on the upper surface of the support portion 82. The adhesion preventing layer 70 is preferably 0.1 μm to 50 μm. The substrate 68 is supported by the support portion 82 via the adhesion preventing layer 70.
The thickness of the plate 88 and the support portion 82 is preferably thicker than the thickness of the substrate 68, respectively, but only the thickness of the support portion 82 may be thicker than the thickness of the substrate 68.

  The plate 88 had a diameter of Φ308 mm and a thickness of 3 mm. The support portion 82 has a diameter of 200 mm and a thickness of 4 mm. The substrate 68 is a silicon wafer having a diameter of 300 mm and a thickness of 700 μm. The adhesion preventing layer 70 made of silicon carbide was 0.1 μm to 50 μm. In the heat treatment, the substrate 68 supported by the substrate support 30 is loaded into a reaction furnace maintained at a temperature of 600 ° C., and after the substrate is loaded, the temperature in the reaction furnace is increased to 1200 ° C. or 1350 ° C., which is the processing temperature. Then, nitrogen (N 2) gas and oxygen (O 2) gas are introduced, the inside of the reaction furnace is maintained at the processing temperature for a predetermined time, and then the temperature in the reaction furnace is lowered to 600 ° C. and supported by the substrate support 30. The substrate 68 was unloaded. It should be noted that the temperature of the substrate 68 was raised and lowered in multiple stages so that the rate of temperature rise and fall became slower as the temperature increased. In this way, the temperature is increased and decreased in multiple stages (the higher the temperature, the lower the temperature increase rate and temperature decrease rate). If the temperature is changed rapidly at a high temperature, the temperature changes uniformly within the substrate surface. This is because it causes slippage. The heat treatment time was about 13 to 14 hours in total. As a result, no slip was observed on the substrate 68 in any case where the processing temperature was 1200 ° C. and 1350 ° C.

[Example 2]
FIG. 12 shows a second embodiment according to the present invention. Similar to the above-described embodiment, for example, a mounting portion 66 is formed to protrude in parallel from the support column 64 on the substrate support 30 whose main body portion is made of silicon carbide. In addition, the support | pillar 64 is provided with two or more, for example, three or four. The plate (base) 88 is made of, for example, a cylindrical plate-like member made of silicon carbide (SiC), and the lower surface periphery of the plate 88 is supported by the mounting portion 66. The plate 88 is mounted with a support portion 58 made of silicon (Si) made of the columnar plate-shaped member described above. Further, an adhesion preventing layer 70 made of, for example, silicon carbide is formed on the upper surface of the support portion 58.

The main body supports a silicon carbide plate 88 having a thickness of 2.5 mm to 3 mm and a diameter of Φ308 mm on a substrate support 30 made of silicon carbide, and has a thickness of 4 mm, a diameter of Φ200 mm, and prevents adhesion to the substrate mounting surface. A silicon support portion 58 coated with a silicon carbide film 70 as a layer was placed, and a substrate 68, which is a silicon wafer having a thickness of 700 μm and a diameter of 300 mm, was placed thereon. In the heat treatment, as shown in FIG. 12, the substrate 68 supported by the substrate support 30 is loaded into a reaction furnace maintained at a temperature of 600 ° C., and after loading the substrate, the inside of the reaction furnace is treated at a temperature of 1350 ° C. The temperature is raised at a stepwise temperature increase rate, and nitrogen (N ₂ ) gas and oxygen (O ₂ ) gas are introduced and the reaction furnace is maintained at the treatment temperature for a predetermined time. The substrate 68 supported by the substrate support 30 was unloaded by changing the temperature decrease rate in steps to 0 ° C. The temperature increase / decrease rate of the substrate 68 was made slower as the temperature increased. That is, the temperature increase rate from 600 ° C to 1000 ° C is slower than the temperature increase rate from room temperature to 600 ° C, and from 1000 ° C than the temperature increase rate from 600 ° C to 1000 ° C. The temperature rising rate from 1200 ° C was slower, and the temperature rising rate from 1200 ° C to 1350 ° C was slower than the temperature rising rate from 1000 ° C to 1200 ° C. Conversely, the temperature decrease rate from 1350 ° C to 1200 ° C is slower than the temperature decrease rate from 1200 ° C to 1000 ° C, and the temperature decrease rate from 1200 ° C to 1000 ° C is 1000 ° C. The temperature lowering rate from ° C to 600 ° C was slower, and the temperature lowering rate from 1000 ° C to 600 ° C was made slower than the temperature lowering rate from 600 ° C to room temperature. In this way, the temperature is increased and decreased in multiple stages (the higher the temperature, the lower the temperature increase rate and temperature decrease rate). If the temperature is changed rapidly at a high temperature, the temperature changes uniformly within the substrate surface. This is because it causes slippage. The heat treatment time was about 13 to 14 hours in total. As a result, when the silicon carbide film 70 was 0.1 μm to 3 μm, no slip occurred on the substrate 68. When the film 70 was 15 μm and 50 μm, almost no slip occurred on the substrate 68.

As a result of repeating the above examples, it was found that slips are less likely to occur in the second and subsequent evaluations than in the first evaluation. This is considered due to the fact that an amorphous SiO ₂ film is formed on the surface of the film 70 on the support portion 58 by the heat treatment in the N ₂ and O ₂ atmosphere in the first evaluation. . By forming this amorphous SiO ₂ film on the outermost surface of the support portion 58, the hardness of the portion of the support portion 58 in contact with the substrate 68 has an SiC film 70 or Si substrate 68 at the time of heat treatment. Even if stress is generated at the contact point between the substrate 68 and the support portion 58 during the high-temperature heat treatment, the stress can be released. In addition, since SiO ₂ is amorphous, even when the substrate 68 and the support 58 are fused at their contact points during high-temperature heat treatment, they are generated at the contact points fused by the viscous flow of the amorphous part. The released stress can be released by the amorphous SiO ₂ viscous flow (viscous deformation). As a result, it is considered that the generation of scratches on the substrate 68 during the high-temperature heat treatment in the second and subsequent evaluations can be suppressed, and the occurrence of slip to the substrate 68 can be suppressed.
In this embodiment, the case where an amorphous SiO ₂ film is formed on the surface of the SiC film 70 provided on the upper surface of the Si support portion 58 has been described. Of course, amorphous SiO ₂ may be directly provided on the surface.

  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. Also good.

The heat treatment apparatus of 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 a SiO ₂ layer is formed inside the wafer (a SiO ₂ layer is embedded) is manufactured.
In addition to the SIMOX wafer, the heat treatment apparatus of the present invention can be applied 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 on which an IC (integrated circuit) is formed can be reduced, and crystal integrity 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 of performing the high-temperature annealing process performed as one step of the substrate manufacturing process as described above, the occurrence of the substrate slip can be prevented by using the heat treatment apparatus of the present invention.

The heat treatment apparatus of 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 a heat treatment step as one step of such a semiconductor device manufacturing step, the occurrence of slip can be prevented by using the heat treatment apparatus of the present invention.

As described above, the present invention is characterized by the matters described in the claims, and further includes the following embodiments.
(1) The heat treatment apparatus according to claim 1, wherein the thickness of the support portion is at least twice the thickness of the substrate.
(2) The heat treatment apparatus according to claim 1, wherein the main body portion has a placement portion on which the support portion is placed, and the thickness of the support portion is larger than the thickness of the placement portion. Heat treatment equipment.
(3) In the heat treatment apparatus according to claim 1, the support portion is formed on a substrate mounting surface on which the substrate is mounted, with silicon nitride (Si ₃ N ₄ ), silicon carbide (SiC), silicon oxide (SiO ₂ ). ), A glassy carbon, or a microcrystalline diamond, one or a plurality of materials are coated.
(4) In the heat treatment apparatus according to claim 1, the support portion has silicon nitride (Si ₃ N ₄ ), silicon carbide (SiC), silicon oxide (SiO ₂ ) on a substrate mounting surface on which the substrate is mounted. ), One or a plurality of chips made of one or a plurality of materials such as glassy carbon and microcrystalline diamond.
(5) The heat treatment apparatus according to claim 1, wherein the support portion is formed with a recess or a groove concentric with the substrate on a substrate placement surface on which the substrate is placed. . (6) The heat treatment apparatus according to claim 1, wherein the support portion is formed with a recess or a concentric groove with the substrate at a peripheral edge of the substrate placement surface on which the substrate is placed. Heat treatment equipment.
(7) In the heat treatment apparatus according to claim 1, the main body portion has a placement portion on which the support portion is placed, and a fitting groove into which the support portion is fitted is formed on the placement portion. A heat treatment apparatus characterized by comprising:
(8) In the heat treatment apparatus according to claim 1, the main body portion includes a placement portion on which the support portion is placed, and an opening or a groove is formed in the placement portion, A heat treatment apparatus, wherein a convex portion that fits into the opening or the groove is provided, and the convex portion of the support portion is fitted into the opening or the groove.
(9) The heat treatment apparatus according to claim 1, wherein the area of the substrate mounting surface of the support portion is smaller than the area of the flat substrate surface.
(10) The heat treatment apparatus according to claim 1, wherein the support portion is cylindrical, and the diameter of the support portion is smaller than the diameter of the substrate.
(11) The heat treatment apparatus according to claim 6, wherein the film pressure of the silicon carbide film is 0.0025% to 1.25% of the thickness of the support portion.
(12) The heat treatment apparatus according to claim 6, wherein a film pressure of the silicon carbide film is 0.0025% to 0.38% of a thickness of the support portion.
(13) The heat treatment apparatus according to claim 6, wherein a film pressure of the silicon carbide film is 0.0025% to 0.25% of a thickness of the support portion.
(14) The heat treatment apparatus according to claim 6, wherein a silicon oxide (SiO2) film is formed on the uppermost surface of the support portion.
(15) In the heat treatment apparatus according to claim 10, the plurality of films include two kinds of films, one of which is a silicon carbide (SiC) film, and the uppermost film is a silicon oxide (SiO2) film. The heat processing apparatus characterized by the above-mentioned.
(16) The heat treatment apparatus according to claim 1, wherein the constituent of the main body is silicon carbide (SiC).
(17) The heat treatment apparatus according to claim 1, wherein the substrate support is configured to support a plurality of substrates in a plurality of stages with a gap in a substantially horizontal state.
(18) The heat treatment apparatus according to claim 1, wherein the heat treatment is performed at a temperature of 1000 ° C. or higher.
(19) The heat treatment apparatus according to claim 1, wherein the heat treatment is performed at a temperature of 1350 ° C. or higher.
(20) A step of carrying the substrate into the processing chamber, a step of supporting the substrate by a support portion made of a silicon plate-like member thicker than the thickness of the substrate, and the substrate in the processing chamber by the support portion. A substrate processing method comprising a step of heat-treating in a supported state and a step of unloading the substrate from the processing chamber.
(21) Any one of silicon carbide (SiC), silicon oxide (SiO ₂ ), glassy carbon, and microcrystalline diamond on the substrate loading surface on which the substrate is placed, and a step of carrying the substrate into the processing chamber Or a step of supporting the substrate by a silicon support portion coated with a film made of a plurality of materials, a step of heat-treating the substrate in a state of being supported by the support portion in the processing chamber, and the processing of the substrate. And a step of unloading from the chamber.
(22) A step of carrying the substrate into the processing chamber, and a plurality of different films are stacked on the substrate mounting surface on which the substrate is mounted, and the hardness of the outermost film among the plurality of films is the smallest at the heat treatment temperature. Or a step of supporting the substrate by a silicon support portion whose outermost film is amorphous, a step of heat-treating the substrate in a state of being supported by the support portion in the processing chamber, and And a step of unloading the substrate from the previous process chamber.
(23) A step of carrying the substrate into the processing chamber, and a plurality of different films are stacked on the substrate mounting surface on which the substrate is mounted, and the hardness of the outermost film among the plurality of films is the smallest at the heat treatment temperature Or a step of supporting the substrate by a silicon support portion whose outermost film is amorphous, a step of heat-treating the substrate in a state of being supported by the support portion in the processing chamber, and And a step of unloading from the previous process chamber.
(24) A step of carrying the substrate into the processing chamber, and a plurality of different films are stacked on the substrate mounting surface on which the substrate is mounted, and the hardness of the outermost film among the plurality of films is the smallest at the heat treatment temperature Or a step of supporting the substrate by a silicon support portion whose outermost film is amorphous, a step of heat-treating the substrate in a state of being supported by the support portion in the processing chamber, and And a step of unloading from the previous process chamber.
(25) A step of carrying the substrate into the processing chamber, and silicon having a silicon carbide (SiC) film formed on the substrate mounting surface on which the substrate is mounted, and further a silicon oxide (SiO ₂ ) film formed on the outermost surface A step of supporting the substrate by a support portion made of metal, a step of heat-treating the substrate in a state of being supported by the support portion in the processing chamber, and a step of unloading the substrate from the processing chamber. A method for manufacturing a substrate.
(26) A step of carrying the substrate into the processing chamber, and silicon having a silicon carbide (SiC) film formed on the substrate mounting surface on which the substrate is mounted, and a silicon oxide (SiO ₂ ) film formed on the outermost surface A step of supporting the substrate by a support portion made of metal, a step of heat-treating the substrate in a state of being supported by the support portion in the processing chamber, and a step of unloading the substrate from the processing chamber. A method for manufacturing a semiconductor device.
(27) A step of carrying the substrate into the processing chamber, and silicon having a silicon carbide (SiC) film formed on the substrate mounting surface on which the substrate is mounted, and further a silicon oxide (SiO ₂ ) film formed on the outermost surface A step of supporting the substrate by a support portion made of metal, a step of heat-treating the substrate in a state of being supported by the support portion in the processing chamber, and a step of unloading the substrate from the processing chamber. A substrate processing method.
(28) A step of carrying the substrate into the processing chamber, and a coating film is formed on the substrate mounting surface on which the substrate is mounted, and the hardness of the coating film is smaller than the hardness of the substrate at the time of heat treatment at the heat treatment temperature, Or a step of supporting the substrate by a support portion made of silicon whose coating film is amorphous, a step of heat-treating the substrate in the processing chamber while being supported by the support portion, and the substrate from the processing chamber And a step of unloading the substrate.
(29) A step of carrying the substrate into the processing chamber, and a coating film is formed on the substrate mounting surface on which the substrate is mounted, and the hardness of the coating film is smaller than the hardness of the substrate at the time of heat treatment at the heat treatment temperature, Or a step of supporting the substrate by a support portion made of silicon whose coating film is amorphous, a step of heat-treating the substrate in the processing chamber while being supported by the support portion, and the substrate from the processing chamber And a step of carrying out the semiconductor device.
(30) A step of carrying the substrate into the processing chamber, and a coating film is formed on the substrate mounting surface on which the substrate is mounted, and the hardness of the coating film is smaller than the hardness of the substrate during the heat treatment at the heat treatment temperature, Or a step of supporting the substrate by a support portion made of silicon whose coating film is amorphous, a step of heat-treating the substrate in the processing chamber while being supported by the support portion, and the substrate from the processing chamber And a step of unloading the substrate.

As described above, according to the present invention, since the substrate is supported by the support portion composed of the plate member made of silicon thicker than the thickness of the substrate, it is possible to prevent the occurrence of slip dislocation defects in the substrate. can do.
Further, according to the present invention, since the silicon support portion is coated with an adhesion prevention layer such as silicon carbide, silicon nitride film, or silicon oxide, it is possible to prevent the substrate from slipping and after heat treatment. Adhesion between the substrate and the support portion can be prevented. In addition, since the hardness of the film coated on the substrate mounting surface of the support portion is smaller than the hardness of the substrate during the heat treatment or the coating film becomes amorphous during the heat treatment, the substrate has slip. It can be further prevented from occurring. In addition, when coating a plurality of films on the substrate mounting surface of the support part, the hardness of the outermost film is the smallest during heat treatment, or the outermost film is made amorphous, so in this case In this case, it is possible to further prevent the substrate from slipping.

  INDUSTRIAL APPLICABILITY The present invention can be used in a heat treatment apparatus, a semiconductor device manufacturing method, and a substrate manufacturing method capable of manufacturing a high-quality semiconductor device by reducing the occurrence of slip dislocation defects in the substrate generated during the heat treatment.

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 an expanded sectional view of the board | substrate support body used for the heat processing apparatus which concerns on embodiment of this invention. It is an enlarged plan view of a substrate support used for a heat treatment apparatus according to an embodiment of the present invention. It is sectional drawing which shows the 1st modification of the board | substrate support body used for the heat processing apparatus which concerns on embodiment of this invention. The 2nd modification of the board | substrate support body used for the heat processing apparatus which concerns on embodiment of this invention is shown, (a) is a top view, (b) is the sectional view on the AA line of (a). The 3rd modification of the board | substrate support body used for the heat processing apparatus which concerns on embodiment of this invention is shown, (a) is a top view, (b) is the BB sectional drawing of (a). It is sectional drawing which shows the 4th modification of the board | substrate support body used for the heat processing apparatus which concerns on embodiment of this invention. It is sectional drawing which shows the various modifications of a support part. It is sectional drawing which shows the board | substrate support body used for the heat processing apparatus which concerns on other embodiment of this invention. It is a diagram which shows the temperature change at the time of the board | substrate process in the Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Heat processing apparatus 30 Substrate support body 40 Reactor 58 Support part 66 Placement part 58 Substrate 74 Fitting groove

Claims (3)

A reactor for processing substrates;
A substrate support for supporting the substrate in the reactor,
The substrate support has a support portion that contacts the substrate and a placement portion on which the support portion is placed, and the placement portion has a groove into which the support portion is fitted. A heat treatment apparatus characterized by A substrate support having a support portion that contacts the substrate and a placement portion on which the support portion is placed, and a groove in which the support portion is fitted is formed on the placement portion. A step of supporting the substrate;
Carrying the substrate supported by the substrate support into a reaction furnace;
Processing the substrate supported by the substrate support in the reactor;
A step of unloading the treated substrate supported by the substrate support from a reaction furnace;
A method for manufacturing a substrate, comprising: A step of supporting the substrate by a substrate support having a support portion in contact with the substrate and a placement portion on which the support portion is placed, and a groove in which the support portion is fitted is formed on the placement portion; When,
Processing the substrate supported by the substrate support;
A step of unloading the treated substrate supported by the substrate support from a reaction furnace;
A method for manufacturing a semiconductor device, comprising:

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