JP2013075789A - Apparatus and method for producing compound semiconductor single crystal - Google Patents

Apparatus and method for producing compound semiconductor single crystal Download PDF

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JP2013075789A
JP2013075789A JP2011216510A JP2011216510A JP2013075789A JP 2013075789 A JP2013075789 A JP 2013075789A JP 2011216510 A JP2011216510 A JP 2011216510A JP 2011216510 A JP2011216510 A JP 2011216510A JP 2013075789 A JP2013075789 A JP 2013075789A
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single crystal
growth
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growth vessel
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Hideyuki Takashima
秀行 高嶋
Tomohisa Kato
智久 加藤
Tomonori Miura
知則 三浦
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Fujikura Ltd
National Institute of Advanced Industrial Science and Technology AIST
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National Institute of Advanced Industrial Science and Technology AIST
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PROBLEM TO BE SOLVED: To provide a production apparatus and production method for compound semiconductor single crystals, capable of further increasing the temperature difference between a single crystal growth surface and a raw material surface, and growing the crystal without lowering the growth rate even in growth over a long period of time.SOLUTION: The production apparatus 100 for producing a single crystal 5 by arranging a seed crystal 9 on one end side and a raw material 6 on the other end side inside a growth vessel 1 and subliming the raw material 6 includes: a heating furnace 4; a heat shielding member 12 arranged around the growth vessel 1, and partitioning the inside of the heating furnace 4 into a low temperature section 17 and a high temperature section 18; a raw material heating means 3 arranged around the other end side of the growth vessel 1 inside the high temperature section 18; and a support part 2 movable in the state of supporting the growth vessel 1. The support part 2 is capable of moving the growth vessel 1 to the side of the low temperature section 17 so that a single crystal growth part 15 is present in the low temperature section 17 and a raw material part 16 is present in the high temperature section 18 when growing the single crystal 5.

Description

本発明は、昇華法を用いた化合物半導体単結晶の製造装置および製造方法に関するものである。  The present invention relates to an apparatus and a method for manufacturing a compound semiconductor single crystal using a sublimation method.

化合物半導体結晶は、複数の元素を組み合わせた半導体結晶であり、発光素子、電子素子、半導体センサ等の半導体デバイスを形成するための材料として有用なものである。化合物半導体は、ケイ素（Ｓｉ）やゲルマニウム（Ｇｅ）などの単元素半導体と比べても大きいバンドギャップを持つことから、絶縁破壊電圧が大きくなるため、高効率パワー半導体デバイスの材料として注目されている。  A compound semiconductor crystal is a semiconductor crystal in which a plurality of elements are combined, and is useful as a material for forming a semiconductor device such as a light emitting element, an electronic element, or a semiconductor sensor. Since compound semiconductors have a larger band gap than single element semiconductors such as silicon (Si) and germanium (Ge), the dielectric breakdown voltage is increased, and thus they are attracting attention as materials for high-efficiency power semiconductor devices. .

このような化合物半導体結晶を製造する方法の１つとしては、昇華再結晶を行う改良型のレーリー法（以下、単に「昇華法」と呼ぶことがある。）が用いられている。
以下、昇華法の原理を説明する。
まず、坩堝を加熱して、坩堝内に配置した粉末原料を高温下で昇華させ、発生した昇華ガスを、上部の蓋に固定された種結晶方向へ拡散、輸送させる。この際、粉末原料に比べ、種結晶が低温になるように温度勾配を設定することにより、蒸気圧の差を発生させ、昇華ガスの拡散方向を種結晶方向へ制御することができる。これにより、種結晶に到着した昇華ガスが、種結晶上で再結晶化することによって、単結晶が成長する。なお、昇華法はＭＯＣＶＤ法（有機金属気相成長法）、ＭＢＥ法（分子線エピタキシー法）などと比べて成長速度が大きいため、大口径単結晶育成に対して有力な方法であり、化合物半導体単結晶（以下、単に「単結晶」と呼ぶことがある。）の大量生産方法として期待されている。 As one method for producing such a compound semiconductor crystal, an improved Rayleigh method for performing sublimation recrystallization (hereinafter sometimes simply referred to as “sublimation method”) is used.
Hereinafter, the principle of the sublimation method will be described.
First, the crucible is heated, the powder raw material placed in the crucible is sublimated at a high temperature, and the generated sublimation gas is diffused and transported in the direction of the seed crystal fixed to the upper lid. At this time, by setting the temperature gradient so that the seed crystal has a lower temperature than the powder raw material, a difference in vapor pressure can be generated and the diffusion direction of the sublimation gas can be controlled in the direction of the seed crystal. As a result, the sublimation gas that has arrived at the seed crystal is recrystallized on the seed crystal, so that a single crystal grows. The sublimation method has a higher growth rate than the MOCVD method (metal organic vapor phase epitaxy), the MBE method (molecular beam epitaxy method), etc., and is therefore an effective method for growing large-diameter single crystals. It is expected as a method for mass production of single crystals (hereinafter sometimes simply referred to as “single crystals”).

昇華法において単結晶の成長速度を向上させるためには、単結晶が成長する成長部、特に結晶表面の温度よりも、原料が設置された原料部、特に原料表面の温度をより高く保つことが必要である。このように成長部と原料部の温度勾配がより急峻になるよう、温度を設定することによって、蒸気圧の差が広がり、過飽和度が高くなるため、結果として、単結晶の成長速度が向上する。そのため、従来の単結晶の製造装置では、成長容器の周囲に複数の加熱手段を配設し、個々の加熱手段の温度制御を行うことにより成長容器内の成長部や原料部の温度を制御している。
しかし、このような従来の単結晶成長装置では、近接する複数の加熱手段からの対流熱や輻射熱により、単結晶成長表面の温度が本来目的とする温度よりも高温になるため、単結晶成長表面と原料表面との温度差が減少し、実際に得られる単結晶の成長速度が予想値よりも低減されてしまう。そのため、従来の単結晶成長装置では、成長容器内の単結晶成長表面と原料表面との温度差の制御には限界があった。 In order to improve the growth rate of the single crystal in the sublimation method, the temperature of the growth part where the single crystal grows, particularly the temperature of the raw material part where the raw material is installed, particularly the surface of the raw material, should be kept higher. is necessary. By setting the temperature so that the temperature gradient between the growth part and the raw material part becomes steeper in this way, the difference in vapor pressure widens and the degree of supersaturation increases, resulting in an increase in the growth rate of the single crystal. . Therefore, in the conventional single crystal manufacturing apparatus, a plurality of heating means are arranged around the growth vessel, and the temperature of the growth part and the raw material part in the growth vessel is controlled by controlling the temperature of each heating means. ing.
However, in such a conventional single crystal growth apparatus, the temperature of the single crystal growth surface becomes higher than the originally intended temperature due to convection heat or radiant heat from a plurality of adjacent heating means. And the temperature difference between the surface of the raw material and the growth rate of the actually obtained single crystal is reduced below the expected value. Therefore, the conventional single crystal growth apparatus has a limit in controlling the temperature difference between the single crystal growth surface and the raw material surface in the growth vessel.

このような問題を解決する方法としては、各加熱手段間に断熱材料を用いた熱遮蔽部材を設けることにより、成長容器内の温度勾配を制御する技術が知られている（例えば、特許文献１参照）。
このような構成にすることによって、近接する複数の加熱手段からの対流熱や輻射熱の遮蔽が可能な化合物半導体単結晶の製造装置が得られる。したがって、単結晶の成長表面と原料部の温度を別々に、かつ、高精度に調節することが可能となり、坩堝の外部の温度分布が一定な状態で坩堝を加熱することが容易となる。 As a method for solving such a problem, a technique for controlling a temperature gradient in a growth vessel by providing a heat shielding member using a heat insulating material between each heating means is known (for example, Patent Document 1). reference).
With this configuration, a compound semiconductor single crystal manufacturing apparatus capable of shielding convection heat and radiant heat from a plurality of adjacent heating means can be obtained. Therefore, the temperature of the growth surface of the single crystal and the temperature of the raw material part can be adjusted separately and with high accuracy, and the crucible can be easily heated with a constant temperature distribution outside the crucible.

特開２００８−２９０８８５号公報JP 2008-290885 A

しかしながら、特許文献１に記載の単結晶の製造方法では、長時間の結晶成長を行う場合、単結晶の成長速度が予想値よりも低減するという問題があった。
単結晶の成長初期には、単結晶成長表面の位置が単結晶を加熱する比較的低温な低温区画に存在するため、原料を加熱する加熱手段からの対流熱や輻射熱を断熱することができる。その結果、成長方向の温度勾配が大きくなるため、成長速度が増大する。ところが、長時間の成長により単結晶の厚さが増加し、単結晶の成長表面の位置が原料を加熱する比較的高温な高温区画に到達すると、原料を加熱する加熱手段からの対流熱や輻射熱によって、単結晶成長表面の温度が本来目的とする温度よりも高温になってしまう。そのため、単結晶成長表面と原料表面との温度差が小さくなり、単結晶の成長速度が低減する。 However, the method for producing a single crystal described in Patent Document 1 has a problem that the growth rate of the single crystal is lower than expected when crystal growth is performed for a long time.
At the initial stage of single crystal growth, the position of the single crystal growth surface is present in a relatively low temperature low temperature section for heating the single crystal, so that convection heat and radiant heat from the heating means for heating the raw material can be insulated. As a result, the temperature gradient in the growth direction increases, and the growth rate increases. However, when the thickness of the single crystal increases due to long-term growth and the position of the growth surface of the single crystal reaches a relatively high temperature high temperature section for heating the raw material, convection heat or radiant heat from a heating means for heating the raw material is obtained. As a result, the temperature of the single crystal growth surface becomes higher than the originally intended temperature. Therefore, the temperature difference between the single crystal growth surface and the raw material surface is reduced, and the growth rate of the single crystal is reduced.

また、特許文献１に記載の単結晶の製造方法では、単結晶成長表面と原料表面との温度差を大きくするために、単結晶を加熱するヒータと、原料を加熱するヒータとの間に熱遮蔽部材が挿入されており、単結晶成長表面と原料表面との温度差を広げることが可能である。しかし、この場合、上記の温度差をほぼ一定の状態に保つことができるだけであって、成長方向の温度勾配がこれ以上増加しないため、成長速度をより向上させるためには、他の手段が必要であった。  In addition, in the method for producing a single crystal described in Patent Document 1, in order to increase the temperature difference between the single crystal growth surface and the raw material surface, heat is generated between the heater for heating the single crystal and the heater for heating the raw material. A shielding member is inserted, and the temperature difference between the single crystal growth surface and the raw material surface can be widened. However, in this case, the above temperature difference can only be kept almost constant, and the temperature gradient in the growth direction does not increase any more, so other means are necessary to further improve the growth rate. Met.

以上の問題点から、従来技術における成長速度のさらなる改善には、単結晶成長表面と原料表面との温度差、すなわち、成長方向の温度勾配の増加や、長時間に亘る成長でも、成長速度が落ちることなく結晶成長を行うことが可能な手段が必要であった。  From the above problems, the further improvement of the growth rate in the prior art can be achieved by increasing the growth rate even when the temperature difference between the single crystal growth surface and the raw material surface, that is, the temperature gradient in the growth direction is increased or the growth is continued for a long time. There was a need for a means capable of crystal growth without falling.

本発明は、上記事情に鑑みてなされたものであって、単結晶成長表面と原料表面との温度差をより一層増加することが可能であると共に、長時間に亘る成長でも、成長速度が落ちることなく結晶成長を行うことが可能な化合物半導体単結晶の製造装置および製造方法を提供することを目的とする。  The present invention has been made in view of the above circumstances, and it is possible to further increase the temperature difference between the surface of the single crystal growth and the surface of the raw material, and the growth rate is lowered even during growth over a long period of time. An object of the present invention is to provide a compound semiconductor single crystal manufacturing apparatus and manufacturing method capable of performing crystal growth without any problem.

上記課題を解決するため、坩堝を支持する支持部自体に着目して鋭意検討した。その結果、支持部を移動させることで、上記課題を解決し得ることを見出し、本発明を完成するに至った。
即ち本発明は、成長容器内の一端側に種結晶を配置し、他端側に原料を配置して、原料を昇華させて化合物半導体単結晶を製造する化合物半導体単結晶の製造装置であって、成長容器を収容する加熱炉と、成長容器の周囲に配置されると共に加熱炉内を低温区画と高温区画に仕切る熱遮蔽部材と、高温区画内にあって成長容器における他端側の周囲に配置される原料加熱手段と、成長容器を支持すると共に成長容器を移動可能な支持部とを備え、支持部は、化合物半導体単結晶を成長させるときに、成長容器内の単結晶成長部が低温区画に存在し、成長容器内の原料部が高温区画に存在するように、低温区画側に成長容器を移動可能であることを特徴とする化合物半導体単結晶の製造装置である。 In order to solve the above-mentioned problems, the inventors studied diligently by paying attention to the support part itself that supports the crucible. As a result, it has been found that the above problem can be solved by moving the support portion, and the present invention has been completed.
That is, the present invention is a compound semiconductor single crystal manufacturing apparatus for manufacturing a compound semiconductor single crystal by arranging a seed crystal on one end side in a growth vessel and arranging a raw material on the other end side and sublimating the raw material. A heating furnace that accommodates the growth vessel, a heat shielding member that is arranged around the growth vessel and partitions the inside of the heating furnace into a low-temperature compartment and a high-temperature compartment, and around the other end of the growth vessel in the high-temperature compartment The raw material heating means arranged and a support part that supports the growth vessel and can move the growth vessel are provided. When the compound semiconductor single crystal is grown in the support part, the single crystal growth part in the growth vessel has a low temperature. The apparatus for producing a compound semiconductor single crystal is characterized in that the growth vessel can be moved to the low temperature compartment side so that the raw material portion in the growth vessel exists in the high temperature compartment.

本発明の化合物半導体単結晶の製造装置によれば、加熱炉内が低温区画と高温区画に仕切ることができるよう成長容器の周囲に熱遮蔽部材が配置され、成長容器内の単結晶成長部が低温区画に、成長容器内の原料部が高温区画に存在できるように保持する。そして、この状態が保たれたまま、単結晶の成長中に、成長容器を支持する支持部が低温区画側に向かって成長容器を移動できるよう設定する。この場合、上記位置関係が保たれることにより、単結晶成長表面の位置を熱遮蔽部材よりも常に上部に保つことができる。したがって、結晶成長が進み、結晶膜厚が増えても、単結晶が原料部を過熱する高温区画に到達することがなくなるので、単結晶の成長表面と原料部との温度差を均一に保つことができ、長時間の結晶成長により単結晶の厚さが増加しても成長速度が落ちることがなく、結晶成長を行うことが可能となる。ここで、高温区画とは原料の昇華温度以上の温度で加熱された区画であり、低温区画とは高温区画よりも低温で加熱された区画である。  According to the compound semiconductor single crystal manufacturing apparatus of the present invention, the heat shielding member is arranged around the growth vessel so that the inside of the heating furnace can be divided into the low temperature compartment and the high temperature compartment, and the single crystal growth portion in the growth vessel is provided. The raw material portion in the growth vessel is held in the low temperature compartment so that it can exist in the high temperature compartment. And while this state is maintained, it sets so that the support part which supports a growth container can move a growth container toward the low temperature division side during the growth of a single crystal. In this case, by maintaining the positional relationship, the position of the single crystal growth surface can always be kept above the heat shielding member. Therefore, even if the crystal growth progresses and the crystal film thickness increases, the single crystal does not reach the high temperature section where the raw material part is heated, so that the temperature difference between the single crystal growth surface and the raw material part is kept uniform. Therefore, even if the thickness of the single crystal increases due to long-time crystal growth, the growth rate does not decrease, and crystal growth can be performed. Here, the high temperature zone is a zone heated at a temperature equal to or higher than the sublimation temperature of the raw material, and the low temperature zone is a zone heated at a lower temperature than the high temperature zone.

また、本発明は、支持部の移動時において、支持部の移動速度が化合物半導体単結晶の成長速度よりも大きいことを特徴とする化合物半導体単結晶の製造装置である。  The present invention is the compound semiconductor single crystal manufacturing apparatus, wherein the moving speed of the support portion is larger than the growth rate of the compound semiconductor single crystal when the support portion is moved.

本発明の化合物半導体単結晶の製造装置によれば、支持部が移動するときに、支持部の移動速度を、単結晶の成長速度よりも大きい移動速度で移動することができるよう設定する。この場合、単結晶の成長が進むにつれ、単結晶の成長表面が、既に設定されていた低温区画である加熱炉の上部側にシフトしていく。そのため、単結晶成長部と原料部との温度差がより大きくなり、従来技術よりも結晶成長速度をより一層向上することができる。  According to the compound semiconductor single crystal manufacturing apparatus of the present invention, when the support portion moves, the moving speed of the support portion is set so that it can be moved at a moving speed larger than the growth rate of the single crystal. In this case, as the growth of the single crystal proceeds, the growth surface of the single crystal shifts to the upper side of the heating furnace, which is a low-temperature section that has already been set. Therefore, the temperature difference between the single crystal growth part and the raw material part becomes larger, and the crystal growth rate can be further improved as compared with the prior art.

また、本発明は、加熱炉内に収容される成長容器内で原料を昇華させて化合物半導体単結晶を製造する化合物半導体単結晶の製造方法であって、熱遮蔽部材が周囲に配置された成長容器を加熱して、加熱炉内を熱遮蔽部材で低温区画と高温区画に仕切る加熱工程と、成長容器内の単結晶成長部を低温区画に、成長容器内の原料部を高温区画に存在するように保ちながら、成長容器を支持する支持部を、成長容器と共に低温区画側に向かって移動させる成長容器移動工程と、を備えたことを特徴とする化合物半導体単結晶の製造方法である。  The present invention also relates to a method for producing a compound semiconductor single crystal in which a raw material is sublimated in a growth vessel accommodated in a heating furnace to produce a compound semiconductor single crystal, in which a heat shielding member is disposed around A heating process in which the vessel is heated and the inside of the heating furnace is divided into a low temperature zone and a high temperature zone by a heat shielding member, the single crystal growth part in the growth vessel is in the low temperature zone, and the raw material part in the growth vessel is in the high temperature zone. And a growth container moving step of moving the supporting portion for supporting the growth container together with the growth container toward the low-temperature compartment side while keeping the growth container in such a manner.

本発明の化合物半導体単結晶の製造方法によれば、加熱炉内を低温区画と高温区画に仕切るように、熱遮蔽部材を成長容器の外周部を取り囲むように用いて、成長容器内の単結晶成長部を低温区画に、原料部を高温区画に存在できるように保持する。そして、この状態を保ちながら、単結晶の成長中に、成長容器を支持する支持部を、成長容器と共に低温区画側に向かって移動させる。この場合、上記位置関係が保たれることにより、単結晶成長表面の位置を熱遮蔽部材よりも常に上部に保つことができる。したがって、結晶成長が進み、結晶膜厚が増えても、単結晶が原料部を加熱する高温区画に到達することがなくなるので、単結晶の成長表面と原料部との温度差を均一に保つことができ、長時間の結晶成長により単結晶の厚さが増加しても成長速度が落ちることがなく、結晶成長を行うことが可能となる。  According to the method for producing a compound semiconductor single crystal of the present invention, the single crystal in the growth vessel is used by surrounding the outer periphery of the growth vessel so that the inside of the heating furnace is divided into the low temperature compartment and the high temperature compartment. The growing part is held in the low temperature compartment and the raw material part is held in the high temperature compartment. Then, while maintaining this state, during the growth of the single crystal, the support portion that supports the growth vessel is moved together with the growth vessel toward the low-temperature compartment side. In this case, by maintaining the positional relationship, the position of the single crystal growth surface can always be kept above the heat shielding member. Therefore, even if the crystal growth progresses and the crystal film thickness increases, the single crystal does not reach the high temperature section for heating the raw material part, so the temperature difference between the growth surface of the single crystal and the raw material part should be kept uniform. Therefore, even if the thickness of the single crystal increases due to long-time crystal growth, the growth rate does not decrease, and crystal growth can be performed.

また、本発明は、成長容器移動工程において、支持部の移動速度が化合物半導体単結晶の成長速度よりも大きくなるように、支持部を移動させることを特徴とする化合物半導体単結晶の製造方法である。  Further, the present invention is a method for producing a compound semiconductor single crystal, wherein the support portion is moved so that the moving speed of the support portion is higher than the growth rate of the compound semiconductor single crystal in the growth vessel moving step. is there.

本発明の化合物半導体単結晶の製造方法によれば、支持部を移動させるときに、支持部の移動速度が化合物半導体単結晶の成長速度よりも大きくなるように、支持部を移動させることにより、単結晶成長が進むにつれ、単結晶の成長表面が、既に設定されていた低温区悪である加熱炉の上部側にシフトしていく。そのため、単結晶成長部と原料部との温度差がより大きくなり、従来技術よりも結晶成長速度をより一層向上することができる。  According to the method for producing a compound semiconductor single crystal of the present invention, when moving the support portion, by moving the support portion so that the moving speed of the support portion is larger than the growth rate of the compound semiconductor single crystal, As the single crystal growth proceeds, the growth surface of the single crystal shifts to the upper side of the heating furnace, which has already been set at a low temperature. Therefore, the temperature difference between the single crystal growth part and the raw material part becomes larger, and the crystal growth rate can be further improved as compared with the prior art.

本発明によれば、従来技術と比べて、単結晶の成長表面と原料表面との温度差をより一層増加させることができ、単結晶の厚さが増加しても成長速度が落ちることなく、結晶成長を行うことが可能な化合物半導体単結晶の製造装置および製造方法を提供することができる。  According to the present invention, compared with the prior art, the temperature difference between the growth surface of the single crystal and the raw material surface can be further increased, and the growth rate does not decrease even if the thickness of the single crystal increases. An apparatus and a method for manufacturing a compound semiconductor single crystal capable of crystal growth can be provided.

本発明に係る化合物半導体単結晶の製造装置の第一実施形態を説明する概略図であって、（ａ）は誘導コイルを用いた場合の化合物半導体単結晶の製造装置を示す概略図、（ｂ）は誘導コイルを用いない場合の化合物半導体単結晶の製造装置を示す概略図である。BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic explaining 1st embodiment of the manufacturing apparatus of the compound semiconductor single crystal which concerns on this invention, Comprising: (a) is the schematic which shows the manufacturing apparatus of the compound semiconductor single crystal at the time of using an induction coil, (b) ) Is a schematic view showing an apparatus for producing a compound semiconductor single crystal when no induction coil is used. 本発明に係る化合物半導体単結晶の製造方法を示すフロー図である。It is a flowchart which shows the manufacturing method of the compound semiconductor single crystal which concerns on this invention. 本発明の第二実施形態に用いられる化合物半導体単結晶の製造装置の概略図である。It is the schematic of the manufacturing apparatus of the compound semiconductor single crystal used for 2nd embodiment of this invention.

（１）第一実施形態
「化合物半導体単結晶の製造装置」
以下、本発明の実施形態について図面を参照しながら詳細に説明する。
図１は、本発明に係る化合物半導体単結晶の製造装置の第一実施形態を説明する概略図であって、（ａ）は誘導コイルを用いた場合の化合物半導体単結晶の製造装置を示す概略図、（ｂ）は誘導コイルを用いない場合の化合物半導体単結晶の製造装置を示す概略図である。
図１（ａ）に示すように、化合物半導体単結晶の製造装置（以下、単に「製造装置」と呼ぶことがある。）１００は、化合物半導体単結晶５の成長が行われる成長容器１と、成長容器１を支持する支持部２と、成長容器１本体の外周に沿って配置され、原料６を加熱する原料加熱手段３と、これら各部を包囲する加熱炉４とから概略構成されている。 (1) First Embodiment “Compound Semiconductor Single Crystal Manufacturing Apparatus”
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic diagram for explaining a first embodiment of a compound semiconductor single crystal manufacturing apparatus according to the present invention. FIG. 1A is a schematic diagram showing a compound semiconductor single crystal manufacturing apparatus using an induction coil. FIG. 2B is a schematic diagram showing an apparatus for producing a compound semiconductor single crystal when no induction coil is used.
As shown in FIG. 1A, a compound semiconductor single crystal manufacturing apparatus (hereinafter sometimes referred to simply as “manufacturing apparatus”) 100 includes a growth vessel 1 in which a compound semiconductor single crystal 5 is grown, The support portion 2 that supports the growth vessel 1, the raw material heating means 3 that heats the raw material 6 and that is disposed along the outer periphery of the growth vessel 1 main body, and the heating furnace 4 that surrounds these portions are roughly configured.

成長容器１は、内底部に単結晶粉末などの原料６が収容される坩堝７と、坩堝７を密閉する蓋体８とを有している。  The growth vessel 1 has a crucible 7 in which a raw material 6 such as single crystal powder is accommodated in an inner bottom portion, and a lid body 8 that seals the crucible 7.

蓋体８は、蓋体８の表面８ａに種結晶９が固定された状態で、種結晶９を坩堝７の内側になるように向けて、坩堝７を密閉するように固定される。以下、蓋体８における種結晶９の固定面を表面８ａと定義する。  The lid 8 is fixed so that the crucible 7 is sealed with the seed crystal 9 facing the inside of the crucible 7 in a state where the seed crystal 9 is fixed to the surface 8 a of the lid 8. Hereinafter, the fixed surface of the seed crystal 9 in the lid 8 is defined as the surface 8a.

坩堝７および蓋体８を構成する材料としては、熱伝導性の材料であれば特に限定されるものではなく、例えば、グラファイト、アルミナ、マグネシア、ジルコニアおよび石英などが用いられる。これらの材料の中でも、経済的、高温耐熱性の観点から、グラファイトを用いることが好ましい。なお、グラファイトを用いると、焼成中に生起される炭素雰囲気により炭素原子が単結晶５に入り込むため、黒鉛が核になって多結晶化したり、炭素ドープにより導電性が増加したりするなど結晶品質の低下が懸念される。したがって、これを防ぐために、坩堝７の内壁面７ａおよび蓋体８の表面８ａは、窒化タングステン等の金属窒化物で被覆されていることが好ましい。  The material constituting the crucible 7 and the lid 8 is not particularly limited as long as it is a heat conductive material. For example, graphite, alumina, magnesia, zirconia, quartz, and the like are used. Among these materials, it is preferable to use graphite from the viewpoint of economy and high temperature heat resistance. In addition, when graphite is used, since carbon atoms enter the single crystal 5 due to the carbon atmosphere generated during firing, the crystal quality is such that the graphite becomes a nucleus and becomes polycrystalline, or the conductivity increases due to carbon doping. There is concern about the decline. Therefore, in order to prevent this, the inner wall surface 7a of the crucible 7 and the surface 8a of the lid 8 are preferably covered with a metal nitride such as tungsten nitride.

支持部２は、成長容器１を支持するために設けられており、成長容器１を載せた状態で上下移動や回転移動が可能な構造となっている。すなわち、結晶成長中に支持部２を上下移動や回転移動させることにより、成長容器１も上下移動もしくは回転移動することが可能となっている。  The support portion 2 is provided to support the growth vessel 1 and has a structure that can be moved up and down or rotated while the growth vessel 1 is placed. That is, the growth vessel 1 can be moved up and down or rotated by moving the support portion 2 up and down and rotating during crystal growth.

また、支持部２の形状は、成長容器１を支持することが可能であれば、Ｔ字型や筒型等のいかなる形状であってもよい。
支持部２の材料としては、熱伝導性や耐熱性に優れた黒鉛やタンタルカーバイド等が用いられるが、タンタルは比較的高価な材料であるため、全体的に黒鉛を使用するか、部分的にタンタルカーバイドを用いることで、コスト削減を図ることができる。 Further, the shape of the support portion 2 may be any shape such as a T-shape or a cylindrical shape as long as the growth vessel 1 can be supported.
As the material of the support portion 2, graphite or tantalum carbide having excellent thermal conductivity and heat resistance is used. However, since tantalum is a relatively expensive material, graphite is used as a whole or partially. Cost reduction can be achieved by using tantalum carbide.

原料加熱手段３の加熱方式としては、誘導加熱による自己発熱方式または抵抗加熱による自己発熱方式が用いられる。
原料加熱手段３は、ヒータ等の抵抗加熱体で構成されている。
抵抗加熱体としては、熱伝導性や耐熱性に優れた黒鉛等のカーボン系材料やタングステン系材料等の材料からなるものが用いられる。 As a heating method of the raw material heating means 3, a self-heating method by induction heating or a self-heating method by resistance heating is used.
The raw material heating means 3 is composed of a resistance heating body such as a heater.
As the resistance heating body, one made of a carbon-based material such as graphite or a tungsten-based material having excellent thermal conductivity and heat resistance is used.

誘導加熱による自己発熱方式を用いる場合、図１（ａ）に示すように、原料加熱手段３と対向するように誘導コイル１０が配設される。この場合、誘導コイル１０は成長容器１本体の外周に沿って螺旋状に巻かれている。
自己発熱方式では、誘導コイル１０に、高周波電流を印加することにより、熱伝導性の材料からなる原料加熱手段３を誘導加熱し、その輻射熱により坩堝７を加熱することができる。
このような誘導加熱による自己発熱方式を用いると、原料加熱手段３は発熱に伴う形状変化が少ないため、寿命が長くなり、結晶成長の安定性とコスト面から有効である。また、誘導コイル１０による発熱の温度を一定に保つためには、誘導コイル１０のコイルピッチを一定に保つ必要があるので、誘導コイル１０のコイルは樹脂系材料で固定されている。なお、使用する誘導コイル１０の個数は特に限定されるものではなく、多数個使用してもよい。 When the self-heating method using induction heating is used, an induction coil 10 is disposed so as to face the raw material heating means 3 as shown in FIG. In this case, the induction coil 10 is spirally wound along the outer periphery of the growth vessel 1 main body.
In the self-heating method, by applying a high frequency current to the induction coil 10, the raw material heating means 3 made of a heat conductive material is induction heated, and the crucible 7 can be heated by the radiant heat.
When such a self-heating method using induction heating is used, the material heating means 3 has little change in shape due to heat generation, so the life is extended, and it is effective in terms of stability and cost of crystal growth. Further, in order to keep the temperature of heat generated by the induction coil 10 constant, it is necessary to keep the coil pitch of the induction coil 10 constant, so the coil of the induction coil 10 is fixed with a resin-based material. The number of induction coils 10 to be used is not particularly limited, and a large number may be used.

抵抗加熱による自己発熱方式を用いる場合、図１（ｂ）に示すように、誘導コイル１０を用いずに、原料加熱手段３に設けられた抵抗体に通電することにより、抵抗体を自己発熱させて、坩堝７を加熱する。  When using the self-heating method by resistance heating, as shown in FIG. 1B, the resistor is self-heated by energizing the resistor provided in the raw material heating means 3 without using the induction coil 10. Then, the crucible 7 is heated.

加熱炉４の外底部４ａには、窒素ガスなどを供給するガス供給装置に接続されたガス導入口（図示略）が設けられている。
また、加熱炉４の天井部４ｂには、加熱炉４内のガスを外部に排出するためのガス排出口（図示略）と、真空ポンプなどの減圧装置に接続されている圧力調整弁（図示略）が設けられており、これらのガス排出口と圧力調整弁により、加熱炉４内を所定のガス圧力に調節できるようになっている。 The outer bottom 4a of the heating furnace 4 is provided with a gas inlet (not shown) connected to a gas supply device that supplies nitrogen gas or the like.
The ceiling 4b of the heating furnace 4 has a gas discharge port (not shown) for discharging the gas in the heating furnace 4 to the outside, and a pressure adjusting valve (not shown) connected to a decompression device such as a vacuum pump. (Omitted) is provided, and the inside of the heating furnace 4 can be adjusted to a predetermined gas pressure by the gas discharge port and the pressure adjusting valve.

結晶成長中に、坩堝７の内壁面７ａおよび蓋体８の表面８ａに被覆されている金属窒化物が昇華するのを防ぐため、坩堝７および加熱炉４の内部には不活性ガスが充填されている。
加熱炉４内のガスが、ガス排出口を通して減圧装置によって排出された後、不活性ガスが、ガス導入口を通して不活性ガス供給装置から加熱炉４内に導入される。
不活性ガスとしては、例えば、アルゴン、ヘリウムもしくはネオン等の希ガス、または、窒素ガスが用いられる。 During the crystal growth, the crucible 7 and the heating furnace 4 are filled with an inert gas to prevent the metal nitride covered on the inner wall surface 7a of the crucible 7 and the surface 8a of the lid 8 from sublimating. ing.
After the gas in the heating furnace 4 is discharged by the decompression device through the gas discharge port, the inert gas is introduced into the heating furnace 4 from the inert gas supply device through the gas introduction port.
As the inert gas, for example, a rare gas such as argon, helium or neon, or nitrogen gas is used.

また、加熱炉４には、成長容器１を収容するための開口部（図示略）が設けられている。
さらに、加熱炉４の上下端部（外底部４ａおよび天井部４ｂ）にはそれぞれ、成長容器１の下面および上面の温度を測定するための放射温度計１１，１１が設けられている。 The heating furnace 4 is provided with an opening (not shown) for accommodating the growth vessel 1.
Furthermore, radiation thermometers 11 and 11 for measuring the temperatures of the lower surface and the upper surface of the growth vessel 1 are provided at the upper and lower end portions (outer bottom portion 4a and ceiling portion 4b) of the heating furnace 4, respectively.

そして、加熱炉４の内部には、成長容器１の外周部を取り囲むように熱遮蔽部材１２が設けられている。
熱遮蔽部材１２の形状は、板状またはブロック状であることが好ましい。また、熱遮蔽部材１２の中心部には、成長容器１の挿通が可能な大きさの開口部１２ａが設けられ、この開口部１２ａに成長容器１が挿通されている。
この場合、完全に他の区画からの熱を遮蔽できるように、熱遮蔽部材１２と成長容器１との間に、出来る限り隙間が生じないように開口部１２ａの大きさを設定するのが望ましい。 And inside the heating furnace 4, the heat shielding member 12 is provided so that the outer peripheral part of the growth container 1 may be surrounded.
The shape of the heat shielding member 12 is preferably a plate shape or a block shape. In addition, an opening 12a having a size that allows the growth vessel 1 to be inserted is provided at the center of the heat shielding member 12, and the growth vessel 1 is inserted through the opening 12a.
In this case, it is desirable to set the size of the opening 12a so that a gap is not generated as much as possible between the heat shielding member 12 and the growth vessel 1 so that heat from other sections can be completely shielded. .

また、上記の熱遮蔽部材１２の代わりに、成長容器１の周囲に、比較的サイズの小さい板状またはブロック状の断熱部材を多数配置させてもよい。
この場合、完全に他の区画からの熱を遮蔽できるように、断熱部材同士の間、断熱部材と成長容器１との間、および、断熱部材と加熱炉４との間を、隙間なく配置することが好ましい。これにより、加熱炉４の内部を、低温区画１７と高温区画１８に仕切ることができる。 Further, instead of the heat shielding member 12, a large number of relatively small plate-like or block-like heat insulating members may be arranged around the growth vessel 1.
In this case, between the heat insulating members, between the heat insulating member and the growth vessel 1, and between the heat insulating member and the heating furnace 4 are arranged without a gap so that heat from other compartments can be completely shielded. It is preferable. Thereby, the inside of the heating furnace 4 can be partitioned into a low temperature compartment 17 and a high temperature compartment 18.

熱遮蔽部材１２を構成する材料としては、多孔質構造をなす断熱性の材料で構成されたものが用いられ、例えば、カーボンフェルト、グラファイトフェルト、リジッドフェルト、カーボンファイバーなどのカーボン繊維系材料、アルミナファイバーやセラミックファイバーなどの非カーボン繊維系材料、ポリウレタンやポリエチレンなどの発泡体材料、マイクロサームなどの粉末系材料または真空断熱材などが挙げられる。これらの中でも、経済的、高遮熱性、高温耐熱性の観点から、カーボン繊維系材料が好ましい。  As the material constituting the heat shielding member 12, a material composed of a heat insulating material having a porous structure is used. For example, carbon fiber materials such as carbon felt, graphite felt, rigid felt, carbon fiber, alumina, etc. Examples thereof include non-carbon fiber materials such as fibers and ceramic fibers, foam materials such as polyurethane and polyethylene, powder materials such as microtherm, and vacuum heat insulating materials. Among these, carbon fiber materials are preferable from the viewpoints of economy, high heat shielding properties, and high temperature heat resistance.

「化合物半導体単結晶の製造方法」
次に、図１および図２を参照して、上記の製造装置１００を用いた本実施形態に係る化合物半導体単結晶の製造方法について説明する。
図２は、本発明に係る化合物半導体単結晶の製造方法を示すフロー図である。 "Production Method of Compound Semiconductor Single Crystal"
Next, with reference to FIG. 1 and FIG. 2, the manufacturing method of the compound semiconductor single crystal which concerns on this embodiment using said manufacturing apparatus 100 is demonstrated.
FIG. 2 is a flowchart showing a method for producing a compound semiconductor single crystal according to the present invention.

まず、加熱炉４に設けられている不図示の搬入口を開けて、加熱炉４内から坩堝７を取り出し、坩堝７の内底部に原料６を収容する（ステップＳ１）。  First, the unillustrated carry-in port provided in the heating furnace 4 is opened, the crucible 7 is taken out from the heating furnace 4, and the raw material 6 is stored in the inner bottom part of the crucible 7 (step S1).

製造装置１００によって製造される化合物半導体単結晶５は、昇華性の単結晶であればいかなるものでもよく、例えば、ＳｉＣ単結晶、ＡｌＮ単結晶およびＧａＮ単結晶などが挙げられる。そして、これらの単結晶の原料としては、これらの粉末の結晶が用いられる。  The compound semiconductor single crystal 5 manufactured by the manufacturing apparatus 100 may be any compound as long as it is a sublimable single crystal, and examples thereof include a SiC single crystal, an AlN single crystal, and a GaN single crystal. These powder crystals are used as raw materials for these single crystals.

次に、蓋体８と種結晶９との間が離間しないように、蓋体８の表面８ａに種結晶９を固定し、蓋体８の表面８ａを坩堝７の内壁面７ａ側に向けて坩堝７を密閉する。この状態で、成長容器１を、加熱炉４の開口部から内底部に収容し、搬入口を閉じて加熱炉４を密閉する（ステップＳ２）。  Next, the seed crystal 9 is fixed to the surface 8 a of the lid 8 so that the lid 8 and the seed crystal 9 are not separated from each other, and the surface 8 a of the lid 8 is directed toward the inner wall surface 7 a of the crucible 7. The crucible 7 is sealed. In this state, the growth vessel 1 is accommodated in the inner bottom portion from the opening of the heating furnace 4, the carry-in port is closed, and the heating furnace 4 is sealed (step S2).

ここで、種結晶９の裏面（蓋体８の表面８ａと接している面）には、種結晶９の裏面からの原子の脱離を防止する目的で、保護膜が設けられていてもよい。
保護膜を構成する材料としては、単結晶５の成長温度における昇華速度が、種結晶９の昇華速度以下である材料であれば特に制限されるものではない。保護膜を構成する材料としては、例えば、感光レジストといった有機薄膜を炭化処理した炭素薄膜などが挙げられる。 Here, a protective film may be provided on the back surface of the seed crystal 9 (the surface in contact with the front surface 8 a of the lid 8) for the purpose of preventing detachment of atoms from the back surface of the seed crystal 9. .
The material constituting the protective film is not particularly limited as long as the material has a sublimation rate at the growth temperature of the single crystal 5 equal to or lower than the sublimation rate of the seed crystal 9. Examples of the material constituting the protective film include a carbon thin film obtained by carbonizing an organic thin film such as a photosensitive resist.

種結晶９としては、単結晶５を成長させることができるものであれば特に限定されるものではなく、例えば、Ｓｉ、Ｇｅなどの単元素半導体からなる半導体結晶基板、ＳｉＣ、ＳｉＧｅなどのＩＶ族化合物半導体からなる半導体結晶基板、Ａｌ２Ｏ３、ＭｇＡｌ２Ｏ４、ＺｎＯ、ＭｇＯまたはＳｉＯ２などの酸化物半導体からなる半導体結晶基板、ＧａＡｓ、ＧａＰ、ＩｎＰ、ＢＮまたはＡｌｘＩｎｙＧａ（１−ｘ−ｙ）Ｎ（ただし、０≦ｘ≦１、０≦ｙ≦１、および０≦ｘ＋ｙ≦１）などのＩＩＩ−Ｖ族化合物半導体などからなる半導体結晶基板が用いられる。これらの中でも、欠陥の少ない高品質の単結晶を効率的に製造する観点から、熱特性に優れる種結晶が好ましく、例えば、ＳｉＣ、Ａｌ２Ｏ３またはＡｌｘＩｎｙＧａ（１−ｘ−ｙ）Ｎ（ただし、０≦ｘ≦１、０≦ｙ≦１、および０≦ｘ＋ｙ≦１）からなる半導体結晶基板が好ましい。 The seed crystal 9 is not particularly limited as long as the single crystal 5 can be grown. For example, a semiconductor crystal substrate made of a single element semiconductor such as Si or Ge, or a group IV such as SiC or SiGe. Semiconductor crystal substrate made of compound semiconductor, semiconductor crystal substrate made of oxide semiconductor such as Al 2 O 3 , MgAl 2 O 4 , ZnO, MgO or SiO 2 , GaAs, GaP, InP, BN or Al x In y Ga (1 -Xy) A semiconductor crystal substrate made of a III-V group compound semiconductor such as N (where 0 ≦ x ≦ 1, 0 ≦ y ≦ 1, and 0 ≦ x + y ≦ 1) is used. Among these, from the viewpoint of efficiently producing a high-quality single crystal with few defects, a seed crystal having excellent thermal characteristics is preferable. For example, SiC, Al 2 O 3 or Al x In y Ga (1-xy) A semiconductor crystal substrate composed of N (where 0 ≦ x ≦ 1, 0 ≦ y ≦ 1, and 0 ≦ x + y ≦ 1) is preferable.

次に、加熱炉４内を、圧力調整弁を介して、減圧装置により真空引きして脱気する（ステップＳ３）。  Next, the inside of the heating furnace 4 is evacuated by vacuuming with a decompression device via a pressure regulating valve (step S3).

その後、ガス導入口から加熱炉４内に不活性ガスを導入するとともに、ガス排出口から加熱炉４内のガスを排出させる。こうして、成長容器１の周囲を不活性ガス雰囲気とする。
なお、この時、加熱炉４内の不活性ガスの圧力は、高品質な単結晶の作製が実現できるように、例えば、単結晶がＳｉＣの場合には１０２Ｐａ以上、単結晶がＡｌＮ、ＧａＮの場合には１０４Ｐａ以上に制御することが好ましい。 Thereafter, an inert gas is introduced into the heating furnace 4 from the gas inlet, and the gas in the heating furnace 4 is discharged from the gas outlet. In this way, the periphery of the growth vessel 1 is made an inert gas atmosphere.
At this time, the pressure of the inert gas in the heating furnace 4 is, for example, 10 2 Pa or more when the single crystal is SiC, and the single crystal is AlN, so that a high-quality single crystal can be produced. In the case of GaN, it is preferable to control to 10 4 Pa or more.

次に、誘導加熱による自己発熱方式を用いる場合、誘導コイル１０に高周波電流を印加することにより、原料加熱手段３に高周波磁場を印加する。すると、原料加熱手段３に誘導電流が流れ、原料加熱手段３が発熱し、その輻射熱により坩堝７が加熱される（ステップＳ４；加熱工程）。また、抵抗加熱による自己発熱方式を用いる場合、原料加熱手段３に設けられた抵抗体に通電することにより、抵抗体が自己発熱し、この熱により坩堝７が加熱される。  Next, when using the self-heating method by induction heating, a high frequency magnetic field is applied to the raw material heating means 3 by applying a high frequency current to the induction coil 10. Then, an induced current flows through the raw material heating means 3, the raw material heating means 3 generates heat, and the crucible 7 is heated by the radiant heat (step S4; heating step). When the self-heating method using resistance heating is used, the resistor is self-heated by energizing the resistor provided in the raw material heating means 3, and the crucible 7 is heated by this heat.

このとき、熱遮蔽部材１２により、原料加熱手段３からの対流熱や輻射熱を抑えることができるので、原料６の温度は種結晶９の温度よりも高温に制御される。したがって、成長容器１内部において温度勾配が形成されるため、坩堝７からの熱が原料６に伝わり、原料６が加熱されて分解、昇華される。これにより、昇華した原料のガスが、ガス導入口から流入した不活性ガスと混合して混合ガスとなる。そして、この混合ガスが蓋体８に固定された種結晶９に付着して再結晶し、化合物半導体単結晶５が成長する。  At this time, since the heat shielding member 12 can suppress convection heat and radiant heat from the raw material heating means 3, the temperature of the raw material 6 is controlled to be higher than the temperature of the seed crystal 9. Therefore, since a temperature gradient is formed inside the growth vessel 1, the heat from the crucible 7 is transmitted to the raw material 6, and the raw material 6 is heated and decomposed and sublimated. As a result, the sublimated raw material gas is mixed with the inert gas flowing in from the gas inlet to become a mixed gas. Then, the mixed gas adheres to the seed crystal 9 fixed to the lid 8 and recrystallizes, so that the compound semiconductor single crystal 5 grows.

ここで、単結晶５の成長温度は、吸着原子の表面マイグレーションを促進できるように、比較的高温であることが望ましい。具体的には、例えば、ＡｌＮ単結晶を得る場合は、成長温度は１５００〜２０００℃程度であることが望ましい。  Here, it is desirable that the growth temperature of the single crystal 5 is relatively high so that surface migration of adsorbed atoms can be promoted. Specifically, for example, when an AlN single crystal is obtained, the growth temperature is preferably about 1500 to 2000 ° C.

また、原料加熱手段３の温度調整は、誘導コイル１０のコイルピッチを変えるだけでなく、誘導コイル１０に印加する高周波電流を制御したり、原料加熱手段３のサイズを変えたりしても可能である。
さらに、原料加熱手段３の輻射熱による成長容器１からの自己発熱を抑えるように、誘導コイル１０の周波数を制御することで、成長容器１内部の温度ムラを防ぐことができ、単結晶成長表面１３と原料表面１４との温度差を適切に保つことが可能となる。
なお、坩堝７内部の雰囲気温度は、種結晶９の温度よりも高温になっているので、上記の混合ガスは、坩堝７の内壁面７ａ側に付着しにくくなり、種結晶９に向かって付着しやすくなる。 The temperature of the raw material heating means 3 can be adjusted not only by changing the coil pitch of the induction coil 10 but also by controlling the high-frequency current applied to the induction coil 10 or changing the size of the raw material heating means 3. is there.
Furthermore, by controlling the frequency of the induction coil 10 so as to suppress the self-heating from the growth vessel 1 due to the radiant heat of the raw material heating means 3, the temperature unevenness inside the growth vessel 1 can be prevented, and the single crystal growth surface 13 And the temperature difference between the raw material surface 14 can be maintained appropriately.
In addition, since the atmospheric temperature inside the crucible 7 is higher than the temperature of the seed crystal 9, the mixed gas is less likely to adhere to the inner wall surface 7 a side of the crucible 7, and adheres toward the seed crystal 9. It becomes easy to do.

また、昇華法による単結晶成長の際、より高品質な単結晶５が得られるように、単結晶成長前において、バッファ層として、種結晶９が昇華しない温度領域で、種結晶９の露出面を覆うように結晶薄膜を成膜してもよい。
ここで、種結晶９の露出面を覆うように成膜された結晶薄膜は、単結晶であることが好ましい。さらに、結晶薄膜と単結晶５とが、同種の物質であることが好ましい。結晶薄膜と同種の物質を用いて単結晶５を成長させると、種結晶９と成長させる単結晶５との格子定数と熱膨張係数が一致する。そのため、異種の物質を用いた場合に比べ、単結晶５と結晶薄膜との格子不整合度をより低減することができ、単結晶５にかかる応力を抑制し、歪による単結晶５の割れを防ぐことができるので、高品質な単結晶５の作製が可能となる。 In addition, when the single crystal is grown by the sublimation method, the exposed surface of the seed crystal 9 is used as a buffer layer in a temperature region where the seed crystal 9 does not sublime before the single crystal growth so that a higher quality single crystal 5 can be obtained. A crystal thin film may be formed to cover the film.
Here, the crystal thin film formed to cover the exposed surface of the seed crystal 9 is preferably a single crystal. Furthermore, the crystal thin film and the single crystal 5 are preferably the same kind of substance. When the single crystal 5 is grown using the same kind of material as the crystal thin film, the lattice constant and the thermal expansion coefficient of the seed crystal 9 and the single crystal 5 to be grown coincide. Therefore, compared to the case of using different kinds of materials, the degree of lattice mismatch between the single crystal 5 and the crystal thin film can be further reduced, the stress applied to the single crystal 5 is suppressed, and the single crystal 5 is not cracked due to strain. Therefore, the high-quality single crystal 5 can be produced.

次に、単結晶成長中に、支持部２を成長容器１とともに低温区画１７側に移動させる（ステップＳ５）。  Next, during the single crystal growth, the support unit 2 is moved together with the growth vessel 1 to the low temperature section 17 side (step S5).

このとき、支持部２の移動速度を、成長容器１内の単結晶成長部１５が低温区画１７に、原料部１６が高温区画１８に存在できる範囲内で、単結晶５の成長速度よりも大きい移動速度に設定する。また、この移動は連続的に行ってもよいし、断続的に行ってもよい。  At this time, the moving speed of the support part 2 is higher than the growth speed of the single crystal 5 within a range in which the single crystal growth part 15 in the growth vessel 1 can exist in the low temperature compartment 17 and the raw material part 16 can exist in the high temperature compartment 18. Set the movement speed. Further, this movement may be performed continuously or intermittently.

さらに、単結晶成長中に、支持部２を回転してもよい。これにより、昇華ガスが種結晶９の表面全体に行き渡り易くなり、種結晶９の表面をより均一な結晶膜厚で覆うことが可能となる。
なお、上記のステップＳ５と支持部２の回転の順序は逆であってもよい。 Furthermore, you may rotate the support part 2 during a single crystal growth. As a result, the sublimation gas easily spreads over the entire surface of the seed crystal 9, and the surface of the seed crystal 9 can be covered with a more uniform crystal film thickness.
Note that the order of the rotation of step S5 and the support portion 2 may be reversed.

以下、本実施形態の作用効果を説明する。
従来、単結晶５の成長初期には、単結晶成長表面１３の位置が、単結晶５を加熱する比較的低温な低温区画１７に存在するため、原料部１６を加熱する原料加熱手段３からの対流熱や輻射熱を断熱することができる。
しかし、長時間の成長により単結晶５の厚さが増加し、単結晶成長表面１３の位置が原料部１６を加熱する比較的高温な高温区画１８に到達すると、原料部１６を加熱する原料加熱手段３からの対流熱や輻射熱により、単結晶成長表面１３の温度が本来目的とする温度よりも高温になるため、単結晶成長表面１３と原料表面１４との温度差が小さくなり、単結晶５の成長速度が低減されてしまう。 Hereinafter, the effect of this embodiment is demonstrated.
Conventionally, at the initial stage of the growth of the single crystal 5, the position of the single crystal growth surface 13 exists in the relatively low temperature low-temperature section 17 that heats the single crystal 5. It is possible to insulate convection heat and radiant heat.
However, when the thickness of the single crystal 5 increases due to the long-time growth and the position of the single crystal growth surface 13 reaches the relatively high temperature high-temperature section 18 for heating the raw material portion 16, the raw material heating for heating the raw material portion 16 is performed. Due to the convection heat and radiant heat from the means 3, the temperature of the single crystal growth surface 13 becomes higher than the originally intended temperature, so that the temperature difference between the single crystal growth surface 13 and the raw material surface 14 becomes small, and the single crystal 5 The growth rate is reduced.

そこで、上記問題の解決手段として、加熱炉４内を低温区画１７と高温区画１８に仕切ることができるように、熱遮蔽部材１２を成長容器１の外周部を取り囲むように用いて、成長容器１内の単結晶成長部１５を低温区画１７に、原料部１６を高温区画１８に存在できるように保持する。
そして、この状態を保ちながら、単結晶５の成長中に、支持部２を成長容器１とともに低温区画１７側に向かって移動させる。この場合、上記位置関係を保つことにより、単結晶成長表面１３の位置を熱遮蔽部材１２よりも常に上部に保つことができる。したがって、結晶成長が進み、単結晶の厚さが増加しても、原料部１６を加熱する高温区画１８に到達することがなくなるので、単結晶成長表面１３と原料表面１４との温度差を均一に保つことができ、長時間の結晶成長により単結晶の厚さが増加しても、成長速度が落ちることがなく結晶成長を行うことが可能となる。 Therefore, as a means for solving the above problem, the growth vessel 1 is used by surrounding the outer periphery of the growth vessel 1 so that the heating furnace 4 can be divided into the low temperature compartment 17 and the high temperature compartment 18. The single crystal growth portion 15 is held in the low temperature compartment 17 and the raw material portion 16 is held in the high temperature compartment 18.
Then, while maintaining this state, during the growth of the single crystal 5, the support portion 2 is moved together with the growth vessel 1 toward the low temperature compartment 17 side. In this case, by maintaining the above positional relationship, the position of the single crystal growth surface 13 can always be kept above the heat shielding member 12. Therefore, even if the crystal growth progresses and the thickness of the single crystal increases, the temperature difference between the single crystal growth surface 13 and the raw material surface 14 is made uniform because the high temperature section 18 for heating the raw material portion 16 is not reached. Therefore, even if the thickness of the single crystal increases due to long-term crystal growth, the crystal growth can be performed without decreasing the growth rate.

また、従来技術においては、単結晶５を加熱する単結晶加熱手段（図示略）と原料部１６を加熱する原料加熱手段３との間に熱遮蔽部材１２を挿入している。これにより、近接する加熱手段からの対流熱や輻射熱を断熱することが可能となり、単結晶成長表面１３と原料表面１４との温度差を広げている。
しかしながら、この場合、上記の温度差はほぼ一定の状態が保たれるだけであって、結晶成長方向の温度勾配がこれ以上増加しないため、成長速度をより向上させるためには、他の手段が必要であった。 In the prior art, the heat shielding member 12 is inserted between the single crystal heating means (not shown) for heating the single crystal 5 and the raw material heating means 3 for heating the raw material portion 16. This makes it possible to insulate convective heat and radiant heat from adjacent heating means, and widen the temperature difference between the single crystal growth surface 13 and the raw material surface 14.
However, in this case, the above temperature difference is only kept almost constant, and the temperature gradient in the crystal growth direction does not increase any more. It was necessary.

そこで、上記問題の解決手段として、本実施形態では、支持部２を移動させるときに、支持部２を、単結晶５の成長速度よりも大きい移動速度で移動させる。支持部２が単結晶５の成長速度と同等の速度で移動する場合、相対速度が同等となるため、事実上、単結晶成長表面１３の位置はほぼ同等の位置に留まることになる。しかし、支持部２を、単結晶５の成長速度よりも大きい移動速度で移動させる場合は、単結晶成長が進むにつれ、単結晶成長表面１３が、既に設定されていた低温区画である加熱炉４の上部側にシフトしていく。そのため、単結晶成長表面１３と原料表面１４との温度差がより大きくなり、従来技術よりも成長速度をより一層向上することができる。  Therefore, as a means for solving the above problem, in the present embodiment, when the support portion 2 is moved, the support portion 2 is moved at a moving speed larger than the growth rate of the single crystal 5. When the support portion 2 moves at a speed equivalent to the growth speed of the single crystal 5, the relative speed becomes equivalent, so that the position of the single crystal growth surface 13 remains in substantially the same position. However, when the support part 2 is moved at a moving speed larger than the growth speed of the single crystal 5, as the single crystal growth proceeds, the heating furnace 4 in which the single crystal growth surface 13 is a low-temperature section that has already been set. Shift to the top of the. Therefore, the temperature difference between the single crystal growth surface 13 and the raw material surface 14 becomes larger, and the growth rate can be further improved as compared with the conventional technique.

（２）第二実施形態
「化合物半導体単結晶の製造装置」
次に、第二実施形態について説明する。
図３は、本発明の第二実施形態に用いられる製造装置１１０の状態を示す概略図である。図３において、図１に示した製造装置１００と同一の構成要素には同一符号を付して、その説明を省略する。
製造装置１１０が、上述の製造装置１００と異なる点は、成長容器１を加熱するために補助加熱手段１９が設けられ、補助加熱手段１９の上部に補助熱遮蔽部材２０が設けられている点である。 (2) Second embodiment “Compound semiconductor single crystal manufacturing apparatus”
Next, a second embodiment will be described.
FIG. 3 is a schematic view showing a state of the manufacturing apparatus 110 used in the second embodiment of the present invention. In FIG. 3, the same components as those of the manufacturing apparatus 100 shown in FIG.
The manufacturing apparatus 110 differs from the manufacturing apparatus 100 described above in that an auxiliary heating means 19 is provided to heat the growth vessel 1 and an auxiliary heat shielding member 20 is provided above the auxiliary heating means 19. is there.

すなわち、製造装置１１０では、原料加熱手段３に加えて、成長容器１を加熱する補助加熱手段１９が、熱遮蔽部材１２の上部、言い換えれば、低温区画１７側に設けられている。
補助加熱手段１９の加熱温度を制御することによって、成長中の単結晶成長表面１３の温度の制御が容易となり、単結晶成長表面１３と原料表面１４との温度差をより一層、適切に制御し易くなる。 That is, in the manufacturing apparatus 110, in addition to the raw material heating means 3, an auxiliary heating means 19 for heating the growth vessel 1 is provided on the upper part of the heat shielding member 12, in other words, on the low temperature compartment 17 side.
By controlling the heating temperature of the auxiliary heating means 19, the temperature of the growing single crystal growth surface 13 can be easily controlled, and the temperature difference between the single crystal growth surface 13 and the raw material surface 14 can be controlled more appropriately. It becomes easy.

また、補助加熱手段１９の上部で、かつ、蓋体８よりも下側に、補助熱遮蔽部材２０が設けられている。
このように補助熱遮蔽部材２０を設けることにより、蓋体８において、補助加熱手段１９からの輻射熱を断熱でき、蓋体８に伝導する熱を抑えることができるため、単結晶成長表面１３と原料表面１４との温度差をさらに適切に制御することが可能となる。 Further, an auxiliary heat shielding member 20 is provided above the auxiliary heating means 19 and below the lid body 8.
By providing the auxiliary heat shielding member 20 in this way, the radiant heat from the auxiliary heating means 19 can be insulated in the lid 8 and the heat conducted to the lid 8 can be suppressed. It becomes possible to further appropriately control the temperature difference with the surface 14.

なお、さらに低温区画１７側に、補助加熱手段１９や補助熱断熱部材２０を設けてもよい。
このように、低温区画１７側に、補助加熱手段１９や補助熱断熱部材２０を設けることにより、低温区画１７側の温度、すなわち単結晶成長表面１３の温度制御を適切に制御できる。
この単結晶加熱手段１９と熱遮蔽部材２０を用いて、上述の第一実施形態と同様の手順で化合物半導体単結晶５を製造してもよい。 In addition, you may provide the auxiliary | assistant heating means 19 and the auxiliary | assistant thermal insulation member 20 in the low temperature division 17 side further.
Thus, by providing the auxiliary heating means 19 and the auxiliary heat insulation member 20 on the low temperature section 17 side, the temperature control on the low temperature section 17 side, that is, the temperature control of the single crystal growth surface 13 can be appropriately controlled.
By using the single crystal heating means 19 and the heat shielding member 20, the compound semiconductor single crystal 5 may be manufactured in the same procedure as in the first embodiment.

１・・・成長容器、２・・・支持部、３・・・原料加熱手段、４・・・加熱炉、５・・・化合物半導体単結晶（単結晶）、６・・・原料、７・・・坩堝、８・・・蓋体（坩堝蓋）、９・・・種結晶、１０・・・誘導コイル、１１・・・放射温度計、１２・・・熱遮蔽部材、１３・・・単結晶成長表面、１４・・・原料表面、１５・・・単結晶成長部、１６・・・原料部、１７・・・低温区画、１８・・・高温区画、１９・・・補助加熱手段、２０・・・補助熱遮蔽部材、１００，１１０・・・化合物半導体単結晶の製造装置（製造装置）。 DESCRIPTION OF SYMBOLS 1 ... Growth container, 2 ... Support part, 3 ... Raw material heating means, 4 ... Heating furnace, 5 ... Compound semiconductor single crystal (single crystal), 6 ... Raw material, 7 · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · Crystal growth surface, 14 ... Raw material surface, 15 ... Single crystal growth part, 16 ... Raw material part, 17 ... Low temperature compartment, 18 ... High temperature compartment, 19 ... Auxiliary heating means, 20 ... Auxiliary heat shielding member, 100, 110 ... Compound semiconductor single crystal manufacturing apparatus (manufacturing apparatus).

Claims (4)

成長容器内の一端側に種結晶を配置し、他端側に原料を配置して、前記原料を昇華させて化合物半導体単結晶を製造する化合物半導体単結晶の製造装置であって、
前記成長容器を収容する加熱炉と、前記成長容器の周囲に配置されると共に前記加熱炉内を低温区画と高温区画に仕切る熱遮蔽部材と、前記高温区画内にあって前記成長容器における他端側の周囲に配置される原料加熱手段と、前記成長容器を支持すると共に前記成長容器を移動可能な支持部とを備え、
前記支持部は、化合物半導体単結晶を成長させるときに、前記成長容器内の単結晶成長部が前記低温区画に存在し、前記成長容器内の原料部が前記高温区画に存在するように、前記低温区画側に前記成長容器を移動可能であることを特徴とする化合物半導体単結晶の製造装置。 A compound semiconductor single crystal manufacturing apparatus for manufacturing a compound semiconductor single crystal by disposing a seed crystal on one end side in a growth vessel and disposing a raw material on the other end side and sublimating the raw material,
A heating furnace that accommodates the growth vessel, a heat shielding member that is disposed around the growth vessel and partitions the heating furnace into a low temperature compartment and a high temperature compartment, and the other end of the growth vessel in the high temperature compartment Comprising a raw material heating means arranged around the side, and a support part that supports the growth vessel and is capable of moving the growth vessel,
When the compound semiconductor single crystal is grown, the support portion is such that the single crystal growth portion in the growth vessel exists in the low temperature compartment, and the raw material portion in the growth vessel exists in the high temperature compartment. An apparatus for producing a compound semiconductor single crystal, wherein the growth vessel is movable to a low-temperature compartment side. 前記支持部の移動時において、前記支持部の移動速度が前記化合物半導体単結晶の成長速度よりも大きいことを特徴とする請求項１に記載の化合物半導体単結晶の製造装置。  2. The apparatus for producing a compound semiconductor single crystal according to claim 1, wherein the moving speed of the supporting portion is higher than the growth rate of the compound semiconductor single crystal when the supporting portion moves. 加熱炉内に収容される成長容器内で原料を昇華させて化合物半導体単結晶を製造する化合物半導体単結晶の製造方法であって、
熱遮蔽部材が周囲に配置された前記成長容器を加熱して、前記加熱炉内を前記熱遮蔽部材で低温区画と高温区画に仕切る加熱工程と、
前記成長容器内の単結晶成長部を前記低温区画に、前記成長容器内の原料部を前記高温区画に存在するように保ちながら、前記成長容器を支持する支持部を、前記成長容器と共に前記低温区画側に向かって移動させる成長容器移動工程と、を備えたことを特徴とする化合物半導体単結晶の製造方法。 A method for producing a compound semiconductor single crystal in which a raw material is sublimated in a growth vessel housed in a heating furnace to produce a compound semiconductor single crystal,
A heating step of heating the growth vessel around which a heat shielding member is disposed, and partitioning the inside of the heating furnace into a low temperature compartment and a high temperature compartment by the heat shielding member;
A supporting portion for supporting the growth vessel is maintained together with the growth vessel while maintaining the single crystal growth portion in the growth vessel in the low temperature compartment and the raw material portion in the growth vessel in the high temperature compartment. And a growth vessel moving step for moving toward the compartment side. A method for producing a compound semiconductor single crystal, comprising: 前記成長容器移動工程において、前記支持部の移動速度が前記化合物半導体単結晶の成長速度よりも大きくなるように、前記支持部を移動させることを特徴とする請求項３に記載の化合物半導体単結晶の製造方法。
4. The compound semiconductor single crystal according to claim 3, wherein in the growth vessel moving step, the support portion is moved so that a moving speed of the support portion is larger than a growth speed of the compound semiconductor single crystal. Manufacturing method.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020203516A1 (en) * 2019-03-29 2020-10-08 学校法人関西学院 Device for manufacturing semiconductor substrate comprising temperature gradient inversion means and method for manufacturing semiconductor substrate
JP7347173B2 (en) 2019-12-04 2023-09-20 株式会社レゾナック crystal growth equipment
JP7373608B1 (en) 2022-05-25 2023-11-02 中外炉工業株式会社 convection suppression furnace

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020203516A1 (en) * 2019-03-29 2020-10-08 学校法人関西学院 Device for manufacturing semiconductor substrate comprising temperature gradient inversion means and method for manufacturing semiconductor substrate
JP7347173B2 (en) 2019-12-04 2023-09-20 株式会社レゾナック crystal growth equipment
JP7373608B1 (en) 2022-05-25 2023-11-02 中外炉工業株式会社 convection suppression furnace

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