JP2013216515A - Manufacturing apparatus and manufacturing method of silicon carbide single crystal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing apparatus and manufacturing method of an SiC single crystal in which temperature distribution of the SiC single crystal surface can be made more uniform, and deterioration of crystal quality can be controlled when growing up the SiC single crystal to be long.SOLUTION: A heating form by a second heating device 13 is changed along with growth of an SiC single crystal 20. Concretely, the SiC single crystal 20 is made longer, an outer peripheral surface is heated more, thereby driving power is increased from a lower side in sequence for each of steps 13a-13c, and a part corresponding to a place in which the SiC single crystal 20 exists is heated in sequence in each of the steps 13a-13c. As a result, temperature distribution can be almost uniform in a longitudinal direction of the SiC single crystal 20, and deterioration of crystal quality of the SiC single crystal 20 can be controlled.

Description

  The present invention relates to a SiC single crystal manufacturing apparatus and manufacturing method for manufacturing a SiC single crystal by supplying a raw material gas to a seed crystal composed of a silicon carbide (hereinafter referred to as SiC) single crystal. .

  Conventionally, as a SiC single crystal manufacturing apparatus, for example, a manufacturing apparatus having a structure shown in Patent Document 1 has been proposed. In this conventional SiC single crystal manufacturing apparatus, a heating coil is arranged so as to surround a cylindrical vacuum vessel, a source gas heating vessel and a crystal growth vessel are arranged inside the vacuum vessel, and the crystal growth vessel is moved up and down. It can be pulled up by a moving mechanism. With such a configuration, the SiC single crystal is grown on the surface of the seed crystal attached to the crystal growth vessel while heating the source gas by heating the source gas heating vessel by induction heating with a heating coil. Further, the SiC single crystal can be grown long by pulling up the crystal growth vessel by the vertical movement mechanism. And the SiC single crystal surface temperature in the elongate direction (growth direction) of a SiC single crystal is controlled by adjusting the power of a heating coil with the long growth of a SiC single crystal. Thereby, the temperature and supersaturation degree of the surface of the SiC single crystal can be controlled, and it is possible to obtain the same growth rate as in the initial stage of growth even during long growth.

JP 2008-169098 A

  However, if the heating coil arranged so as to surround the periphery of the SiC single crystal as in Patent Document 1 is a single one, the temperature distribution in the longitudinal direction is controlled even if the temperature of the surface of the SiC single crystal is controlled. However, the longer the growth, the more the temperature distribution is generated in the longitudinal direction and the thermal stress is generated. For this reason, there is a problem in that defects increase due to thermal stress generated in the growing SiC single crystal and the crystal quality is deteriorated.

  In view of the above points, the present invention provides a SiC single crystal manufacturing apparatus and a manufacturing method capable of making the temperature distribution on the surface of the SiC single crystal more uniform and suppressing deterioration in crystal quality when the SiC single crystal is grown long. For the purpose.

  In order to achieve the above object, according to the first aspect of the present invention, a seed crystal (5) made of a SiC single crystal substrate is installed on the pedestal (9), and the periphery of the pedestal is heated by a heating device (13). On the other hand, the SiC single crystal (20) is grown on the surface of the seed crystal by supplying the SiC source gas (3a) to the surface of the seed crystal, and the pedestal is pulled up by the pulling mechanism (11). In a SiC single crystal manufacturing apparatus that lengthens a single crystal, the heating device includes a heating coil and a multi-stage structure in which heating coils are arranged in multiple stages (13a to 13c) in the growth direction of the SiC single crystal. In addition, each stage of the heating coil is configured to be temperature-controlled independently.

  Thus, the heating coil which comprises a heating apparatus is set as the multistage structure, and it is set as the structure which can control temperature independently at each stage. For this reason, fine temperature control accompanying the growth of the SiC single crystal can be performed by temperature control by each stage of the heating coil. As a result, the temperature distribution of the growth surface of the SiC single crystal can be adjusted to a temperature suitable for the growth of the SiC single crystal, and the temperature of the outer peripheral surface of the SiC single crystal during the long growth can be controlled almost uniformly. It becomes possible to suppress the deterioration of the crystal quality of.

  In the invention according to claim 3, the heating device is configured by a heating coil, and the heating coil has a multi-stage structure in which the heating coils are arranged in multiple stages (13a to 13c) in the growth direction of the SiC single crystal, and each stage of the heating coil is formed. The temperature can be controlled independently, and the pedestal is pulled up by a pulling mechanism in accordance with the growth of the SiC single crystal, so that the height of the growth surface of the SiC single crystal is kept constant while the SiC single crystal It is characterized by controlling each stage of the heating coil in accordance with the growth.

  Thus, the heating mode by the heating device is changed with the growth of the SiC single crystal. For example, as in the invention described in claim 4, heating is performed by driving the first stage in a state where the surface of the seed crystal is arranged at a position corresponding to the first stage (13 a) located at the lowermost position among the multiple stages. The SiC single crystal is started to grow while performing, and the driving power is increased in order from the lower of the multiple stages as the SiC single crystal grows. Thereby, the temperature distribution can be made substantially uniform in the longitudinal direction of the SiC single crystal, and deterioration of the crystal quality of the SiC single crystal can be suppressed.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows an example of a corresponding relationship with the specific means as described in embodiment mentioned later.

It is sectional drawing of the SiC single crystal manufacturing apparatus 1 concerning 1st Embodiment of this invention. It is the figure which showed the control form of the drive electric power of each stage 13a-13c of the 2nd heating apparatus 13 with the growth of the SiC single crystal 20. FIG. It is the figure which showed the temperature distribution in the elongate direction of the SiC single crystal 20 at the time of heating with the control form shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be described with the same reference numerals.

(First embodiment)
As shown in FIG. 1, the SiC single crystal manufacturing apparatus 1 supplies a source gas 3a from a source gas supply source 3 through an inlet 2 provided at the bottom and out of the source gas 3a through an outlet 4 at the top. Unreacted gas is discharged. Then, the SiC single crystal manufacturing apparatus 1 forms an ingot of the SiC single crystal 20 by growing the SiC single crystal 20 on the seed crystal 5 made of the SiC single crystal substrate disposed in the apparatus.

  The SiC single crystal manufacturing apparatus 1 includes a source gas supply source 3, a vacuum container 6, a first heat insulating material 7, a heating container 8, a pedestal 9, a second heat insulating material 10, a rotary pulling mechanism 11, first and second heating. Devices 12 and 13, interference preventing member 14, purge gas supply source 15 and pyrometer 16 (16 a to 16 f) are provided.

  The source gas supply source 3 supplies an SiC source gas 3 a containing Si and C together with a carrier gas (for example, a mixed gas of a silane-based gas such as silane and a hydrocarbon-based gas such as propane) from the inlet 2.

  The vacuum vessel 6 is made of quartz glass or the like, has a hollow cylindrical shape, can introduce and lead the carrier gas and the source gas 3a, and accommodates other components of the SiC single crystal manufacturing apparatus 1. The structure is such that the internal space in which it is housed can be depressurized by evacuating it. The inlet 2 of the source gas 3a is provided at the bottom of the vacuum vessel 6, and the outlet 4 of the source gas 3a is provided at the upper part (specifically, the position above the side wall).

  The first heat insulating material 7 has a cylindrical shape, is disposed coaxially with respect to the vacuum vessel 6, and constitutes a raw material gas introduction pipe 7 a with a hollow portion. The first heat insulating material 7 is made of, for example, graphite or graphite whose surface is coated with a refractory metal carbide such as TaC (tantalum carbide) or NbC (niobium carbide) so that thermal etching can be suppressed. Yes.

  Heating vessel 8 is formed in a hollow shape, and constitutes a reaction chamber in which SiC single crystal 20 is grown on the surface of seed crystal 5. The heating container 8 is made of, for example, graphite or graphite whose surface is coated with a refractory metal carbide such as TaC (tantalum carbide) or NbC (niobium carbide), so that thermal etching can be suppressed. The heating container 8 is arranged from the upstream side in the flow direction of the raw material gas 3 a to the downstream side with respect to the base 9 so as to surround the base 9. By this heating container 8, the raw material gas 3 a is decomposed while excluding particles contained in the raw material gas 3 a until the raw material gas 3 a supplied from the inlet 2 is led to the seed crystal 5.

  Specifically, the heating container 8 has a structure having a hollow cylindrical member, and in the case of the present embodiment, the heating container 8 is composed of a bottomed cylindrical member. The heating vessel 8 is provided with a gas introduction port 8a that communicates with the hollow portion of the first heat insulating material 7 at the bottom, and the source gas 3a that has passed through the hollow portion of the first heat insulating material 7 is heated through the gas introduction port 8a. It is introduced into the container 8.

  Further, a purge gas introduction hole 8 b is provided on the inner peripheral wall surface of the heating container 8 on the upstream side of the pedestal 9 in the flow direction of the raw material gas 3 a. Through this purge gas introduction hole 8b, a purge gas 15a supplied from a purge gas supply source 15 to be described later is introduced into the heating container 8 and flows through a gap between the heating container 8 and the base 9. The purge gas introduction hole 8 b is formed so as to surround the entire inner periphery of the heating container 8, and introduces the purge gas 15 a so as to surround the periphery of the base 9.

  The pedestal 9 is composed of a plate-like member that is arranged coaxially with the central axis of the heating container 8. For example, the pedestal 9 is made of graphite or graphite whose surface is coated with a refractory metal carbide such as TaC (tantalum carbide) or NbC (niobium carbide) so that thermal etching can be suppressed. A seed crystal 5 is attached to the pedestal 9, and a SiC single crystal 20 is grown on the surface of the seed crystal 5. The pedestal 9 has a shape corresponding to the shape of the seed crystal 5 to be grown, for example, a disk shape, and is connected to the rotary pulling mechanism 11 on the surface opposite to the surface on which the seed crystal 5 is disposed.

  The second heat insulating material 10 constitutes an outer peripheral heat insulating material that guides the purge gas 15 a into the heating container 8 while surrounding the outer periphery of the heating container 8 and the base 9. In the present embodiment, the second heat insulating material 10 is formed in a cylindrical shape, for example, graphite or graphite whose surface is coated with a refractory metal carbide such as TaC (tantalum carbide) or NbC (niobium carbide). As a result, thermal etching can be suppressed. The inner diameter of the second heat insulating material 10 is made larger than the outer diameters of the first heat insulating material 7 and the heating container 8, and a gap for introducing the purge gas 15a is formed between them. Although not shown in the drawing, the inner diameter of the second heat insulating material 10 can be reduced upward, and with such a configuration, the purge gas 15a can be further discharged to the purge gas introduction hole 8b side.

  The rotary pulling mechanism 11 rotates and pulls the pedestal 9 through the pipe material 11a. One end of the pipe material 11 a is connected to the surface of the pedestal 9 on the side opposite to the attaching surface of the seed crystal 5, and the other end is connected to the main body of the rotary pulling mechanism 11. The pipe material 11a is also made of, for example, graphite or graphite whose surface is coated with a refractory metal carbide such as TaC (tantalum carbide), so that thermal etching can be suppressed. With such a configuration, the pedestal 9, the seed crystal 5 and the SiC single crystal 20 can be rotated and pulled together with the pipe material 11a, and the SiC single crystal 20 is grown while the growth surface of the SiC single crystal 20 has a desired temperature distribution. The growth surface temperature can always be adjusted to a temperature suitable for growth.

  The first and second heating devices 12 and 13 are constituted by heating coils (induction heating coils and direct heating coils), and are arranged so as to surround the vacuum vessel 6. In the case of this embodiment, the 1st, 2nd heating apparatuses 12 and 13 are comprised by the coil for induction heating, for example, it is set as the structure which can cool the inside by water with the coil for induction heating. The first and second heating devices 12 and 13 are configured to be able to independently control the temperature, and the first heating device 12 is disposed at a position corresponding to the lower side of the heating container 8 to perform the second heating. The device 13 is disposed at a position corresponding to the base 9. Therefore, the temperature of the lower part of the heating container 8 can be controlled by the first heating device 12, and the temperature around the pedestal 9, the seed crystal 5 and the SiC single crystal 20 can be controlled by the second heating device 13. .

  Moreover, about the 2nd heating apparatus 13, it is set as the multistage structure in which the 1st-3rd step 13a-13c was arranged in the elongate direction (growth direction) of the SiC single crystal 20 made to grow further long. Each of the stages 13a to 13c is driven by a separate electric circuit, and is configured such that temperature control of each of the stages 13a to 13c can be performed independently. Each stage 13a-13c is arrange | positioned at predetermined intervals, and the space | interval is 10 mm or more and 100 mm or less. In the case of the present embodiment, the intervals of the respective steps 13a to 13c are set to be equal intervals, the length of the ingot of the SiC single crystal 20 to be elongated is assumed to be 100 mm, and the interval is set to 50 mm.

  Each step 13a to 13c is arranged so as to surround SiC single crystal 20 in the longitudinal direction after the long growth. Specifically, the first stage 13a is located most upstream in the flow direction of the source gas 3a, and the pedestal 9 is pulled down most by the rotary pulling mechanism 11, that is, before the growth of the SiC single crystal 20 In this state, it is arranged at a position corresponding to the surface of the seed crystal 5. The second stage 13b is arranged between the first stage 13a and the third stage 13c, and is arranged so that the temperature distribution on the surface of the SiC single crystal 20 is as uniform as possible inside the first to third stages 13a to 13c. It is preferable that they are arranged at equal intervals from the first stage 13a and the third stage 13c. The third stage 13 c is arranged at a position corresponding to the position of the seed crystal 5 after the SiC single crystal 20 is grown long, that is, after being pulled up by the rotary pulling mechanism 11.

  These stages 13a to 13c are set so as not to interfere with each other during heating. For example, since the 2nd heating device 13 is comprised by a heating coil, each stage 13a-13c may receive interference by electromagnetic induction, and may become unable to exhibit desired power. For this reason, for example, the drive frequencies of the stages 13a to 13c are varied so that the mutual interference that prevents the desired power from being exhibited is suppressed, and the drive frequencies of the stages 13a to 13c are approximated to frequencies or multiplication frequencies. It is not to be. For example, the frequency of each stage 13a-13c can be 3 kHz, 5 kHz, and 7 kHz. In addition, each of the steps 13a to 13c is moved in the longitudinal direction of the SiC single crystal 20, thereby enabling fine adjustment of the arrangement location in the longitudinal direction.

  Thus, the 2nd heating apparatus 13 is set as the multistage structure, and it is set as the structure which can carry out temperature control of each stage 13a-13c independently. For this reason, fine temperature control accompanying the growth of SiC single crystal 20 can be performed by temperature control by each stage 13a-13c. Thereby, the temperature distribution of the growth surface of the SiC single crystal 20 can be adjusted to a temperature suitable for the growth of the SiC single crystal 20, and the temperature of the surface (outer peripheral surface) of the SiC single crystal 20 during the long growth is substantially uniform. Can be controlled. Therefore, it is possible to suppress the deterioration of the crystal quality of SiC single crystal 20.

  Of the second heating device 13, the one located most downstream in the flow direction of the source gas 3 a (the third stage 13 c in this embodiment) is more than the position of the base 9 after the long growth of the SiC single crystal 20. Furthermore, it can also arrange | position so that it may be located in the flow direction downstream. However, in the present embodiment, the downstream side is prevented from being heated by preventing the second heating device 13 from being disposed downstream of the base 9 in the flow direction of the raw material gas 3a.

  The interference preventing member 14 is disposed between the stages 13a to 13c of the second heating device 13 having a multistage configuration so that mutual interference between the stages 13a to 13c is further suppressed. The interference preventing member 14 is made of, for example, an interference preventing coil made of copper and capable of cooling the inside with water.

The purge gas supply source 15 supplies the purge gas 15a. The purge gas 15a is composed of an inert gas such as Ar or He, or an etching gas such as H ₂ or HCl, and functions as an adhesion preventing gas for preventing the deposition of SiC polycrystal. The purge gas 15a supplied from the purge gas supply source 15 passes through the clearance between the outer peripheral wall of the first heat insulating material 7 and the heating container 8 and the inner peripheral wall of the second heat insulating material 10 and passes through the purge gas introduction hole 8b to enter the heating container 8. To be introduced.

  A plurality of pyrometers 16 are provided so as to perform temperature measurement at a plurality of locations inside the SiC single crystal manufacturing apparatus 1. The first meter 16a measures the growth surface temperature of the SiC single crystal 20 through the source gas introduction pipe 7a and the gas introduction port 8a. The second to fifth meters 16b to 16e are arranged side by side in the longitudinal direction of the SiC single crystal 20, and the gaps between the steps 13a to 13c and the interference prevention member 14 constituting the second heating device 13 (2) The surface temperature of the outer peripheral surface of the SiC single crystal 20 and the like is measured through the through holes or slits formed in the heat insulating material 10 and the heating container 8. The sixth meter 16 f measures the back surface temperature of the base 9.

  With this structure, the SiC single crystal manufacturing apparatus 1 according to the present embodiment is configured. Then, the manufacturing method of the SiC single crystal 20 using the SiC single crystal manufacturing apparatus 1 concerning this embodiment is demonstrated with reference to FIG. 2 and FIG.

  First, the seed crystal 5 is attached to the pedestal 9 and installed in the heating container 8. At this time, as shown in FIG. 2 (b), the surface of the seed crystal 5 is arranged at a position corresponding to the first stage 13 a located at the lowest position in the second heating device 13. And the 1st, 2nd heating apparatuses 12 and 13 are controlled and desired temperature distribution is attached. That is, the source gas 3a is recrystallized on the surface of the seed crystal 5 so that the SiC single crystal grows and the sublimation rate becomes higher in the heating vessel 8 than the recrystallization rate. To do. Specifically, as shown in FIG. 2A, for the second heating device 13, the first stage 13a is driven with 10 kW of power, and the second stage 13b is driven with 5 kW of power lower than the first stage 13a. To drive. The third stage 13c is not driven at this time with the power set to 0 kW. By doing in this way, the back surface side of the base 9 can be prevented from being heated very much, heating the surface side of the seed crystal 5 which should grow the SiC single crystal 20.

In addition, the source gas 3a is introduced through the source gas introduction pipe 7a while introducing a carrier gas using an inert gas such as Ar or He or an etching gas such as H ₂ or HCl while bringing the vacuum vessel 6 to a desired pressure. To do. Thereby, source gas 3a flows as shown by an arrow in FIG. 1, and is supplied to seed crystal 5 to grow SiC single crystal 20. Then, the base 9, the seed crystal 5, and the SiC single crystal 20 are rotated through the pipe material 11 a by the rotary pulling mechanism 11, and pulled up according to the growth rate of the SiC single crystal 20. Thereby, the height of the growth surface of SiC single crystal 20 is kept substantially constant, and the temperature distribution of the growth surface temperature can be controlled with good controllability.

A purge gas composed of an inert gas such as Ar or He or an etching gas such as H ₂ or HCl is introduced from the purge gas supply source 15 through the purge gas introduction hole 8b. As a result, the purge gas 15a is caused to flow toward the outlet 4 through the purge gas introduction hole 8b and the pedestal 9 or between the SiC single crystal 20 and the heating vessel 8 as shown by the arrows in FIG. For this reason, it is possible to suppress the formation of polycrystals around the pedestal 9 and the inner peripheral wall surface of the heating container 8 due to the influence of the purge gas 15a. As a result, it is possible to suppress the formation of polycrystals in the portion located around the seed crystal 5 and to prevent clogging of the flow path of the source gas 3a due to the growth of the polycrystals. Single crystal growth is possible.

  Furthermore, the pyrometers 16a to 16f are used to measure the temperature of the growth surface of the SiC single crystal 20, the outer peripheral surface of the SiC single crystal 20, and the back surface of the pedestal 9, and the results are fed back to the first and second heating devices 12, 13 is finely adjusted so that the temperature of each part becomes a desired temperature. For example, the electric power supplied to each stage 13a-13c which comprises the 2nd heating apparatus 13 is finely adjusted, or these arrangement | positions are finely adjusted.

  In this way, the SiC single crystal 20 is grown. At the initial growth stage of the SiC single crystal 20, the power supply to the second heating device 13 is set to the above-described form, and the length (long amount) is the first stage. The configuration is continued until the interval between 13a and the second stage 13b. Then, when the SiC single crystal 20 grows and the length becomes about a length (here, 50 mm) corresponding to the distance between the first stage 13a and the second stage 13b, the power supply of the second heating device 13 is Change form. Specifically, as shown in FIG. 2B, the first stage 13a and the second stage 13b are driven with 10 kW of power, and the third stage 13c is 5 kW lower than the first stage 13a and the second stage 13b. Drive with the power of. By doing in this way, the outer peripheral surface of the SiC single crystal 20 can be heated while heating the surface side of the seed crystal 5 on which the SiC single crystal 20 is to be grown, and the back surface side of the base 9 is not heated so much. Can be.

  When the SiC single crystal 20 further grows and its length (long amount) reaches a length (here, 100 mm) corresponding to the distance between the first stage 13a and the third stage 13c, the second heating is performed. The power supply mode of the device 13 is changed again. Specifically, as shown in FIG. 2C, all the stages 13a to 13c are driven with 10 kW of power. By doing in this way, the outer peripheral surface of the SiC single crystal 20 can be heated while heating the surface side of the seed crystal 5 on which the SiC single crystal 20 is to be grown, and the back surface side of the base 9 is not heated so much. Can be. Thereafter, when the length of the SiC single crystal 20 reaches 100 mm, the growth of the SiC single crystal 20 is finished.

  In this way, the SiC single crystal 20 is grown, and the heating mode by the second heating device 13 is changed as the SiC single crystal 20 grows. Specifically, in order to heat the outer peripheral surface as the SiC single crystal 20 becomes longer, the driving power is increased in order from the bottom for each of the stages 13a to 13c, and the SiC single crystal of each of the stages 13a to 13c. The portion corresponding to the place where 20 is present is heated in order. As a result, the temperature distribution in the longitudinal direction of SiC single crystal 20 can be made substantially uniform, and the deterioration of the crystal quality of SiC single crystal 20 can be suppressed. For example, as shown in FIG. 3, when the heating mode of the present embodiment is used, the temperature distribution within the thickness of the SiC single crystal 20 can be made more uniform as compared with the prior art.

  In order to dissipate the SiC single crystal 20, it is necessary to cool the back surface side of the SiC single crystal 20, but crystal defects such as slip dislocations are generated in the SiC single crystal 20 even with a small thermal stress of, for example, several MPa or less. . For this reason, it is necessary to reduce the temperature gradient inside the SiC single crystal 20, and for this purpose, the temperature distribution on the outer peripheral surface of the SiC single crystal 20 becomes uniform and the temperature gradient needs to be reduced.

  On the other hand, in this embodiment, the heating mode by the second heating device 13 is changed as the SiC single crystal 20 grows. Therefore, the temperature distribution on the outer peripheral surface of the SiC single crystal 20 can be made substantially uniform and the temperature gradient can be reduced while cooling the back surface side of the SiC single crystal 20 in accordance with the growth of the SiC single crystal 20. Accordingly, it is possible to obtain an ingot of the SiC single crystal 20 that is grown long with few crystal defects.

  In addition, when the SiC single crystal manufacturing apparatus 1 of the present embodiment is used and when the second heating apparatus 13 uses a structure in which each stage 13a to 13c cannot be controlled independently as in the conventional case, the SiC single crystal 20 The temperature difference between the front and back surfaces of the SiC single crystal 20 and the shear stress distribution inside the crystal were confirmed. As a result, when the SiC single crystal manufacturing apparatus 1 of the present embodiment was used, the temperature difference between the front and back surfaces of the SiC single crystal 20 was 200 ° C., and the shear stress was not generated inside the crystal. In addition, when the conventional structure was used, the temperature difference between the front and back surfaces of the SiC single crystal 20 was 400 ° C., and the shear stress was generated inside the crystal. Also from this, by using the SiC single crystal manufacturing apparatus 1 of the present embodiment, the temperature distribution on the outer peripheral surface of the SiC single crystal 20 can be made substantially uniform, the temperature gradient can be reduced, and crystal defects can be suppressed. I understand that

(Other embodiments)
In the above embodiment, as the SiC single crystal manufacturing apparatus 1, after the source gas 3 a is supplied to the growth surface of the SiC single crystal 20, it passes through the outer peripheral surface of the SiC single crystal 20 and the side of the pedestal 9 and is discharged further upward. The method (upflow method) is described as an example. However, the present invention is not limited to this, and a return flow method in which the source gas 3a is supplied to the growth surface of the SiC single crystal 20 and then returned again in the same direction as the supply direction, or the source gas 3a is applied to the growth surface of the SiC single crystal 20. It can also be applied to a method (side flow method) in which the gas is discharged in the outer peripheral direction of the heating container 8 after being supplied.

  The present invention can also be applied to a growth method different from the gas supply method growth for supplying the source gas 3a. That is, SiC raw material powder is placed in advance in a crucible placed in a vacuum vessel, a raw material gas obtained by sublimating the SiC raw material from the SiC raw material powder is generated by heating with a heating device, and an SiC single crystal is formed on the seed crystal surface. The present invention can also be applied to sublimation growth for growth.

  In the above embodiment, the pyrometer 16 is used for temperature measurement, but a thermocouple may be used instead of the pyrometer 16. For example, it can be used as the second to fifth meters 16b to 16e by installing a thermocouple for the second heat insulating material 10 and detecting the temperature of each part based on the output of the thermocouple. Further, the rotary pulling mechanism 12 capable of both rotating and pulling up the pedestal 9 has been described as an example, but at least a pulling mechanism capable of pulling up may be used.

  It should be noted that the number of stages 13a to 13c constituting the second heating device 13 described in the above embodiment and the interval between the stages 13a to 13c can be changed as appropriate, and the length of the SiC single crystal 20 to be grown long. It may be set according to.

DESCRIPTION OF SYMBOLS 1 Single crystal manufacturing apparatus 3a Source gas 5 Seed crystal 8 Heating container 9 Base 10 2nd heat insulating material 11 Rotation pulling mechanism 11a Pipe material 12, 13 1st, 2nd heating apparatus 13a-13c Each stage 14 Interference prevention member 16 Pyrometer 20 SiC single crystal

Claims (8)

A hollow heating vessel (8) constituting the reaction chamber;
A pedestal (9) disposed in the heating vessel;
A heating device (13) that is disposed at a position corresponding to the pedestal of the outer periphery of the heating container and heats the heating container;
A lifting mechanism (11) for pulling up the pedestal upward;
A seed crystal (5) made of a silicon carbide single crystal substrate is installed on the pedestal, and a silicon carbide source gas (3a) is supplied to the surface of the seed crystal while heating the periphery of the pedestal with the heating device. Thus, the silicon carbide single crystal (20) is grown on the surface of the seed crystal, and the silicon carbide single crystal is elongated by pulling up the pedestal by the pulling mechanism. A device,
The heating device includes a heating coil and has a multistage structure in which the heating coils are arranged in multiple stages (13a to 13c) in the growth direction of the silicon carbide single crystal, and each stage of the heating coil includes An apparatus for producing a silicon carbide single crystal, characterized in that the temperature is controlled independently.   The silicon carbide single crystal according to claim 1, wherein an interference preventing member (14) for preventing mutual interference when driving each stage is installed between each stage of the heating coil. Manufacturing equipment. A hollow heating vessel (8) constituting the reaction chamber;
A pedestal (9) disposed in the heating vessel;
A heating device (13) that is disposed at a position corresponding to the pedestal of the outer periphery of the heating container and heats the heating container;
Using a manufacturing apparatus (1) having a pulling mechanism (11) for pulling up the pedestal upward,
A seed crystal (5) made of a silicon carbide single crystal substrate is installed on the pedestal, and a silicon carbide source gas (3a) is supplied to the surface of the seed crystal while heating the periphery of the pedestal with the heating device. Thus, the silicon carbide single crystal (20) is grown on the surface of the seed crystal, and the silicon carbide single crystal is elongated by pulling up the pedestal by the pulling mechanism. A method,
The heating device is constituted by a heating coil and has a multistage structure in which the heating coils are arranged in multiple stages (13a to 13c) in the growth direction of the silicon carbide single crystal, and each stage of the heating coil is independently heated. Configured to control,
By pulling up the pedestal by the pulling mechanism in accordance with the growth of the silicon carbide single crystal, the height of the growth surface of the silicon carbide single crystal is kept constant and the growth of the silicon carbide single crystal is adjusted. A method for producing a silicon carbide single crystal, wherein each stage of the heating coil is controlled.   The silicon carbide single crystal is heated while driving the first stage (13a) in a state where the surface of the seed crystal is arranged at a position corresponding to the first stage (13a) located at the lowest position among the multistages. 4. The method for producing a silicon carbide single crystal according to claim 3, wherein the driving power is increased in order from the lower of the multistage as the silicon carbide single crystal grows. 5.   The silicon carbide single crystal begins to grow in a state where the first stage (13a) is driven with higher power than the remaining stages (13b, 13c), and the multistage as the silicon carbide single crystal grows. 5. The method for producing a silicon carbide single crystal according to claim 4, wherein the driving power is increased in order from the lower side to obtain the first stage driving power. 6.   4. The method for producing a silicon carbide single crystal according to claim 3, wherein the driving frequency of each stage of the heating coil is varied.   The interference preventing member (14) for preventing mutual interference when each of the stages is driven is installed between the stages of the heating coil. A method for producing a silicon carbide single crystal.   The temperature of the growth surface of the said SiC single crystal, a back surface, and an outer peripheral surface is measured, The said heating coil is controlled based on the result of this temperature measurement, The one of Claim 3 thru | or 7 characterized by the above-mentioned. A method for producing a silicon carbide single crystal.

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