JP3799865B2

JP3799865B2 - Graphite crucible for single crystal pulling apparatus and single crystal pulling apparatus

Info

Publication number: JP3799865B2
Application number: JP07103199A
Authority: JP
Inventors: 丈生斉藤; 啓成安部; 智司工藤; 貴熱海
Original assignee: Sumco Corp
Current assignee: Sumco Corp
Priority date: 1999-03-16
Filing date: 1999-03-16
Publication date: 2006-07-19
Anticipated expiration: 2019-03-16
Also published as: JP2000264777A

Description

【０００１】
【発明の属する技術分野】
本発明は、半導体融液を貯留する石英ルツボを支持するための単結晶引上装置用黒鉛ルツボおよび単結晶引上装置に関するものである。
【０００２】
【従来の技術】
従来、シリコン（Ｓｉ）やガリウムひ素（ＧａＡｓ）等の半導体単結晶を成長する方法の一つとして、ＣＺ法が知られている。
このＣＺ法は、大口径、高純度の単結晶が無転位あるいは格子欠陥の極めて少ない状態で容易に得られること等の特徴を有することから、様々な半導体結晶の成長に用いられている方法である。
【０００３】
近年、単結晶の大口径化、高純度化、酸素濃度および不純物濃度等の均一化の要求に伴いこのＣＺ法も様々に改良され実用に供されている。
上記ＣＺ法の改良型の一つにいわゆる二重ルツボを用いた連続チャージ型磁界印加ＣＺ法（以下、ＣＭＣＺ法と省略する）が提案されている。この方法は、外部からルツボ内の半導体融液に磁界を印加することにより、前記半導体融液内の対流を抑制し極めて酸素濃度の制御性がよく単結晶化率がよい単結晶を成長させることができ、外側のルツボと内側のルツボとの間に原料を連続供給し長尺の半導体単結晶を容易に得ることができる等の特徴を有する。したがって、大口径かつ長尺の半導体単結晶を得るには最も優れた方法の一つと言われている。
【０００４】
図５は、特開平４−３０５０９１号公報に記載されている、上記のＣＭＣＺ法を用いたシリコンの単結晶引上装置の一例である。この単結晶引上装置１は、中空の気密容器であるチャンバ２内に二重ルツボ（石英ルツボ）３、ヒーター４、原料供給管５がそれぞれ配置され、前記チャンバ２の外部にマグネット６が配置されている。
なお、後述する本発明は、ＣＭＣＺ法による単結晶引上装置に適用されるに限らず、例えば、磁界印加を行わない連続チャージ型ＣＺ法（ＣＣＺ法）による単結晶引上装置や、二重ルツボではなく１つのルツボを備えた単結晶引上装置にも適用できる。
【０００５】
二重ルツボ３は、略半球状の石英（ＳｉＯ₂）製の外ルツボ（後述する石英ルツボ）１１と、該外ルツボ１１内に設けられた円筒状の仕切り体である石英（ＳｉＯ₂）製の内ルツボ１２とから構成され、該内ルツボ１２の側壁には、内ルツボ１２と外ルツボ１１との間（原料融解領域）と内ルツボ１２の内側（結晶成長領域）とを連通する連通孔１３が複数個形成されている。
【０００６】
この二重ルツボ３は、チャンバ２の中央下部に垂直に立設されたシャフト１４上の黒鉛ルツボ（サセプタ）１５に収容されて載置されており、前記シャフト１４の軸線を中心として水平面上で所定の角速度で回転する構成になっている。そして、この二重ルツボ３内には半導体融液（加熱融解された半導体単結晶の原料）２１が貯留されている。
図６に示すように、黒鉛ルツボ１５はその半径方向の分割線に沿って分割された３つの分割部材１５ａ、１５ｂ、１５ｃからなり、各分割部材１５ａ、１５ｂ、１５ｃの底面には、前記シャフト１４（図５参照）のフランジ部１４ａが嵌め込まれる凹部２０ａ、２０ｂ（分割部材１５ｃに形成された凹部は不図示）がそれぞれ形成されている。黒鉛ルツボ１５をその半径方向に分割した理由は、それに及ぼされる熱応力を逃がして、割れを防止するためである。
【０００７】
ほぼ円筒状のヒーター４は、半導体の原料をルツボ内で加熱・融解するとともに生じた半導体融液２１を保温するもので、通常、抵抗加熱ヒーターが用いられる。原料供給手段としての原料供給管５は、その下端開口より、所定量の半導体の原料１０を外ルツボ１１と内ルツボ１２との間の半導体融液２１面上に連続的に投入するものである。
【０００８】
上記の原料供給管５から供給される原料１０としては、例えば、多結晶シリコンのインゴットを破砕機等で破砕してフレーク状にしたもの、あるいは、気体原料から熱分解法により粒状に析出させた多結晶シリコンの顆粒が好適に用いられ、必要に応じてホウ素（Ｂ）（ｐ型シリコン単結晶を作る場合）やリン（Ｐ）（ｎ型シリコン単結晶を作る場合）等のドーパントと呼ばれる添加元素がさらに供給される。
また、ガリウムヒ素（ＧａＡｓ）の場合も同様で、この場合、添加元素は亜鉛（Ｚｎ）もしくはシリコン（Ｓｉ）等となる。
【０００９】
上記の単結晶引上装置１により、内ルツボ１２の上方かつ軸線上に配された引上軸２４にチャック（不図示）を介して種結晶２５を吊下げ、引上軸２４をその軸線回りに回転させつつ引上げることにより、半導体融液２１上部において種結晶２５を核として半導体単結晶２６を成長させる。
【００１０】
ところで、上記の単結晶引上装置では、特開昭６３−３０３８９４号公報に記載されているように、単結晶を成長する前工程において、外ルツボ１１に予め多結晶シリコン塊等の多結晶原料を融解させて半導体融液２１を貯留し、外ルツボ１１の上方に配された内ルツボ１２を、外ルツボ１１内に載置して、二重ルツボ３を形成している。
【００１１】
このように多結晶原料を融解後に二重ルツボ３を形成するのは、多結晶原料を完全に融解して半導体融液２１を得るために、ヒーター４によって外ルツボ１１内の原料を単結晶成長温度以上の温度まで高温加熱する必要があり、この際に、予め内ルツボ１２を外ルツボ１１内に形成させていると、内ルツボ１２に大きな熱変形が生じてしまうからである。
【００１２】
したがって、原料を完全に融解した後、ヒーター４による加熱をある程度弱めてから内ルツボ１２を外ルツボ１１に形成させることによって、初期原料融解保持時の高温加熱を避け、内ルツボ１２の変形を抑制している。
【００１３】
また、内ルツボ１２に形成された連通孔１３は、原料供給時に、半導体融液２１を外ルツボ１１側から内ルツボ１２内にのみ流入させるように一定の開口面積以下に設定されている。この理由は、結晶成長領域から半導体融液２１が対流により原料融解領域に戻る現象が生じると、単結晶成長における不純物濃度および融液温度等の制御が困難になってしまうためである。
【００１４】
【発明が解決しようとする課題】
しかしながら、ルツボ構造は、図６に示すように、分割構造の黒鉛ルツボ１５内に石英ルツボ１１を単に収容した構造なので、単結晶製造の進行に伴って、石英ルツボ１１から発生したガス（種類はＳｉＯ）と、黒鉛ルツボ１５の分割線近傍（以下、分割部１６ａ、１６ｂ、１６ｃという。）の特に湾曲部１７ａ、１７ｂ、１７ｃ（図６中で１点鎖線で囲まれた部分）との反応により、この部分は欠損して薄肉化する。この薄肉化によりその欠損部の肉厚が規定値以下になったら、黒鉛ルツボ１５全体を新品のものに交換しなければならない。これにより、黒鉛ルツボ１５の寿命が短くなって、交換頻度が多くなり、結果的に、ランニングコストが高くつくという問題点がある。
【００１５】
ここで、黒鉛ルツボ１５の分割部１６ａ、１６ｂ、１６ｃが欠損しやすい原因は、以下のとおりに推測される。
すなわち、先ず、石英ルツボ１１から発生したＳｉＯガスと黒鉛ルツボ１５とが反応して、ＣがＣＯガスとして黒鉛ルツボ１５から離脱するような反応が起こると推測される（以下の反応式参照）。
ＳｉＯ＋２Ｃ→ＳｉＣ＋ＣＯ↑
そして、半導体単結晶成長工程中において、石英ルツボ１１が高温雰囲気に晒されることに起因して、石英ルツボ１１が変形して黒鉛ルツボ１５に密着し、ＳｉＯガスの通り道が分割部１６ａ、１６ｂ、１６ｃに集中する。この分割部１６ａ、１６ｂ、１６ｃ付近では、生成されたＣＯガスがこの分割部１６ａ、１６ｂ、１６ｃを通って黒鉛ルツボ１５外へ移動しやすいため、ＣＯガス濃度が上昇しにくく、その結果、上記の反応が促進される。
また、分割部１６ａ、１６ｂ、１６ｃの中でも、特に湾曲部１７ａ、１７ｂ、１７ｃが欠損しやすいのは、以下のような理由による。炉内において単結晶成長軸方向の温度分布は、下部側ほど、また、半径方向外側ほど高温になって前記反応が進行しやすい。一方、黒鉛ルツボ１５はフランジ１４ａに載置されているので、黒鉛ルツボ１５の底面からはＣＯガスが逃げにくいので、反応が進行しにくい。こうして、底面に近い下部に位置する湾曲部１７ａ、１７ｂ、１７ｃは、最も欠損しやすい部位となる。
石英ルツボ１１が黒鉛ルツボ１５に密着した状態でさらに変形して拡径すると、分割部材１５ａ、１５ｂ、１５は半径方向外方に変位して、ＣＯガスの通り道である分割部１６ａ、１６ｂ、１６ｃの隙間が大きくなり、上記反応はさらに促進されることになる。
【００１６】
さらに、このような黒鉛ルツボ１５の分割部１６ａ、１６ｂ、１６ｃの欠損促進を放置しておくと、黒鉛ルツボ１５の薄肉化による形状の変化に伴って、石英ルツボ１１も変形して薄くなるので、石英ルツボ１１内の半導体融液が流出する可能性が高くなるという問題点もある。
また、石英ルツボ１１の変形した部分の曲率が小さいことから、石英ルツボ１１内の半導体融液に流れ（乱流）が生じやすく、結果的に、半導体の単結晶化率が低下するという問題点もある。
【００１７】
本発明は、上述した事情に鑑みてなされたものであり、石英ルツボから発生したＳｉＯガスと黒鉛ルツボとの反応が抑制されることにより黒鉛ルツボの寿命が延びてランニングコストが低減する上に、単結晶化率も向上する単結晶引上装置用黒鉛ルツボおよび単結晶引上装置を提供することを目的としている。
【００１８】
【課題を解決するための手段】
上記目的を達成するための本発明は、以下の構成を採用した。
本発明の単結晶引上装置用黒鉛ルツボは、半導体融液を貯留する石英ルツボを支持するための単結晶引上装置用黒鉛ルツボにおいて、前記黒鉛ルツボが、半径方向の分割線に沿って分割された複数の分割部材と該分割部材の半径方向外方への変位を規制する変位規制部材とを備えていることを特徴とする。この単結晶引上装置用黒鉛ルツボは、変位規制部材を備えることにより、分割部材の半径方向外方への変位を規制され、分割部の隙間が大きくなることが防止される。また、変位規制部材を備えているので、分割部材の位置ずれを防止できる。
【００１９】
本発明の単結晶引上装置用黒鉛ルツボは、上記の単結晶引上装置用黒鉛ルツボにおいて、前記黒鉛ルツボが底部と側部とから構成され、該側部は前記複数の分割部材からなり、前記底部は前記変位規制部材であり、前記複数の分割部材の下端部に周方向に沿う係合部が形成され、前記変位規制部材の周縁部に周方向に沿い、前記係合部に係合する係合受け部が形成されていることを特徴とする。この単結晶引上装置用黒鉛ルツボでは、分割部材に設けられた係合部に底部をなす変位規制部材に設けられた係合受け部を係合させるという簡単な構成により、分割部材の半径方向外方への変位を防止でき、分割部の隙間が大きくなることが防止される。
【００２０】
本発明の単結晶引上装置用黒鉛ルツボは、上記の単結晶引上装置用黒鉛ルツボにおいて、前記係合部は平坦な面で形成された段部であり、前記係合受け部は該段部に上方から当接する平坦な面で形成されたつば部であることを特徴とする。この単結晶引上装置用黒鉛ルツボでは、石英ルツボの変形に伴って黒鉛ルツボの開口部近傍を拡径する力が作用するとき、底部のつば部が分割部材の段部を押さえることにより、分割部材の変位を規制することができる。従って、分割部の隙間が大きくなることを防止できる。
【００２１】
本発明の単結晶引上装置用黒鉛ルツボは、上記の単結晶引上装置用黒鉛ルツボにおいて、前記段部または前記つば部のいずれか一方に溝部が形成され、他方に該溝部に係合する凸部が形成されていることを特徴とする。この単結晶引上装置用黒鉛ルツボでは、底部と分割部材が係合が溝部と凸部とによりなされているので、鉛直方向を除く広範囲の方向の分割部材の変位を規制することができる。従って、分割部の隙間が大きくなることを防止できる。
【００２２】
本発明の単結晶引上装置は、上記のいずれかに記載の単結晶引上装置用黒鉛ルツボを備えたことを特徴とする。この単結晶引上装置は、変位規制部材を有する黒鉛ルツボが設けられているので、分割部材の半径方向外方への変位を規制し、ＣＯガスの通り道である分割部の隙間が大きくなることが防止され、石英ルツボから発生したＳｉＯガスと黒鉛ルツボの分割部の特に湾曲部との反応を抑制でき、黒鉛ルツボの湾曲部の薄肉化を防止できるので、黒鉛ルツボの寿命を延ばし、ランニングコストの削減可能である。また、黒鉛ルツボの薄肉化による形状の変化に伴う石英ルツボの変形が抑制できるので、石英ルツボ内の半導体融液が流出する可能性が低減されている。さらに、石英ルツボが変形した部分は半導体融液に流れ（乱流）が生じて半導体の単結晶化率が低下するが、そのような変形が抑制されるので、単結晶化率が高いインゴットの製造が可能である。
【００２３】
本発明の単結晶引上装置は、半導体融液を貯留する石英ルツボを支持するための黒鉛ルツボと該黒鉛ルツボを下方より支持する黒鉛ルツボ支持台を備えた単結晶引上装置において、前記黒鉛ルツボが半径方向の分割線に沿って分割された複数の分割部材からなり、該複数の分割部材の外側の下部周縁部には周方向に沿うテ−パ部が設けられ、前記黒鉛ルツボ支持台の上面周縁部には周方向に沿い、前記テ−パ部に着接して前記複数の分割部材を支持するテ−パ受け部が形成されていることを特徴とする。この単結晶引上装置は、従来の黒鉛ルツボと黒鉛ルツボ支持台にそれぞれテ−パ部およびテ−パ受け部を設けることにより、分割部材の半径方向外方への変位を規制して、ＣＯガスの通り道である分割部の隙間が大きくなることを防止し、石英ルツボから発生したＳｉＯガスと黒鉛ルツボとの反応を抑制する。
【００２４】
【発明の実施の形態】
以下、本発明に係る単結晶引上装置用黒鉛ルツボおよび単結晶引上装置の好適な実施の形態を図面を参照して説明する。
尚、図５および図６において既に説明した同等な構成要素に対しては、同符号を付してその説明を省略する。
【００２５】
まず、第一の実施形態を図１および図２を参照して説明する。
本実施形態の単結晶引上装置用黒鉛ルツボ３１（以下、単に黒鉛ルツボ３１という。）は、底部３２と側部３３とから構成され、その側部３３は３つの分割部材３３ａ、３３ｂ、３３ｃからなり、底部３２は変位規制部材３２であり、３つの分割部材３３ａ、３３ｂ、３３ｃのそれぞれの下端部に周方向に沿う平坦な面で形成された段部（係合部）３４、３４、３４が形成され、一方、変位規制部材３２の周縁部に周方向に沿い、前記段部３４、３４、３４に上方から当接する平坦な面で形成されたつば部（係合受け部）３５、３５、３５が形成されている。
【００２６】
この黒鉛ルツボ３１では、石英ルツボ１１の特に開口部が変形して拡径することにより、分割部材３３ａ、３３ｂ、３３ｃの上部が半径方向外方に力を受け、その段部３４、３４、３４が図２の矢印に示すように力を受けた場合、変位規制部材３２のつば部３５、３５、３５により上方から押さえられる。そのため、分割部材３３ａ、３３ｂ、３３ｃは半径方向外方に変位できないので、ＣＯガスの通り道である分割部１６ａ、１６ｂ、１６ｃの隙間が大きくなることが防止され、石英ルツボ１１から発生したＳｉＯガスと黒鉛ルツボ３１の分割部１６ａ、１６ｂ、１６ｃの特に湾曲部１７ａ、１７ｂ、１７ｃとの反応が抑制される。
【００２７】
また、変位規制部材３２により、分割部材３３ａ、３３ｂ、３３ｃの位置ずれが防止できるので、位置ずれによる分割部１６ａ、１６ｂ、１６ｃの隙間の増大も防止できる。
【００２８】
そのため、この反応に伴う分割部１６ａ、１６ｂ、１６ｃの特に湾曲部１７ａ、１７ｂ、１７ｃの薄肉化が抑制されるので、黒鉛ルツボ３１の寿命が延び、ランニングコストの削減が可能になる。
また、そのような黒鉛ルツボ３１の分割部１６ａ、１６ｂ、１６ｃの特に湾曲部１７ａ、１７ｂ、１７ｃの薄肉化による形状の変化に伴って、石英ルツボ１１が変形して薄くなることも抑制されるので、石英ルツボ１１内の半導体融液が流出する可能性を低減できる。
さらには、石英ルツボ１１が変形した部分は半導体融液に流れ（乱流）が生じて半導体の単結晶化率が低下するが、そのような変形が抑制されるので、単結晶化率が向上する。
【００２９】
次に、第二の実施形態について、図３を参照して説明する。
上述の第一の実施形態と同等な構成要素に対しては、同符号を付してその説明を省略する。
この実施形態では、図３に示すように、第一の実施形態における分割部材３３ａ、３３ｂ、３３ｃの段部３４、３４、３４に溝部３６、３６、３６が形成され、また、変位規制部材３２のつば部３５、３５、３５にその溝部３６、３６、３６に係合する凸部３７、３７、３７が形成されている点が第一の実施形態との相違である。
【００３０】
この場合、分割部材３３ａ、３３ｂ、３３ｃが図３の矢印に示すような力を受けても、分割部材３３ａ、３３ｂ、３３ｃの溝部３６、３６、３６が変位規制部材３２の凸部３７、３７、３７に係合されているので、変位できない。したがって、ＣＯガスの通り道である分割部１６ａ、１６ｂ、１６ｃの隙間が大きくなることが防止されるので、石英ルツボ１１から発生したＳｉＯガスと黒鉛ルツボ３１との反応が抑制される。
【００３１】
次に、第三の実施形態について、図４を参照して説明する。
上述の第一および第二の実施形態と同等な構成要素に対しては、同符号を付してその説明を省略する。
この単結晶引上装置では、半径方向の分割線に沿って分割された３つの分割部材１５ａ、１５ｂ（分割部材１５ｃは不図示）からなる黒鉛ルツボ１５と該黒鉛ルツボ１５を下方より支持する黒鉛ルツボ支持台（図６中のフランジ部と同等の構成要素）１４ａを備えた単結晶引上装置において、３つの分割部材１５ａ、１５ｂ、１５ｃの外側の下部周縁部には周方向に沿うテ−パ部４０ａ、４０ｂ、４０ｃ（テ−パ部４０ｃは不図示）が設けられ、黒鉛ルツボ支持台１４ａの上面周縁部には周方向に沿い、テ−パ部４０ａ、４０ｂ、４０ｃに着接して３つの分割部材１５ａ、１５ｂ、１５ｃを支持するテ−パ受け部４１が形成されている。ここで、３つの分割部材１５ａ、１５ｂ、１５ｃの外側底面部４２ａ、４２ｂ、４２ｃ（外側底面部４２ｃは不図示）は、黒鉛ルツボ支持台１４ａの上面部１４ｂに接しない構成としているので、３つの分割部材１５ａ、１５ｂ、１５ｃは、黒鉛ルツボ支持台１４ａのテ−パ受け部４１だけで支持している。
【００３２】
この実施形態では、テ−パ部４０ａ、４０ｂ、４０ｃは、分割部材自身の重量のテ−パ部４０ａ、４０ｂ、４０ｃに垂直な方向の成分の力を受けているので、３つの分割部材１５ａ、１５ｂ、１５ｃは半径方向外方に変位することができない。この場合、３つの分割部材１５ａ、１５ｂ、１５ｃを黒鉛ルツボ支持台１４ａのテ−パ受け部４１だけで支持する構成にすることで、その変位を効果的に規制している。そのため、ＣＯガスの通り道である分割部１６ａ、１６ｂ、１６ｃ（図４不図示）の隙間が大きくなることが防止されるので、石英ルツボ１１から発生したＳｉＯガスと黒鉛ルツボ１５との反応が抑制される。
【００３３】
尚、上記実施形態において説明した黒鉛ルツボ１５、あるいは黒鉛ルツボ３１は、３分割のものに限らず、その他の数に分割されていてもよい。
【００３４】
【発明の効果】
以上詳細に説明したように、本発明によれば、以下のような効果を奏する。
【００３５】
本発明の単結晶引上装置用黒鉛ルツボによれば、変位規制部材を備えているので、分割部材の半径方向外方への変位を規制することにより、分割部の隙間が大きくなることが防止できるので、石英ルツボから発生したＳｉＯガスと黒鉛ルツボとの反応を抑制でき、黒鉛ルツボの薄肉化を防止できるので、黒鉛ルツボの寿命を延ばし、ランニングコストの削減できるという効果を得ることができる。また、黒鉛ルツボの薄肉化による形状の変化に伴石英ルツボの変形が抑制できるので、石英ルツボ内の半導体融液が流出する可能性を低減できるという効果を得ることができる。さらに、石英ルツボが変形した部分は半導体融液に流れ（乱流）が生じて半導体の単結晶化率が低下するが、そのような変形が抑制されるので、単結晶化率が向上させることができるという効果が得られる。また、分割部材の位置ずれによる分割部の隙間が大きくなることが防止できるという効果が得られる。
【００３６】
本発明の単結晶引上装置用黒鉛ルツボによれば、分割部材に設けられた係合部に底部をなす変位規制部材に設けられた係合受け部を係合させるという簡単な構成により、上記の効果と同様な効果を得られる。
【００３７】
本発明の単結晶引上装置用黒鉛ルツボによれば、石英ルツボの変形に伴って黒鉛ルツボの開口部近傍を拡径する力が作用するとき、底部のつば部が分割部材の段部を押さえることにより、分割部材の変位を規制することができる。従って、分割部の隙間が大きくなることを防止できるという効果が得られる。
【００３８】
本発明の単結晶引上装置用黒鉛ルツボによれば、底部と分割部材が係合が溝部と凸部とによりなされているので、鉛直方向を除く広範囲の方向の分割部材の変位を規制することができる。従って、分割部の隙間が大きくなることを防止できるという効果が得られる。
【００３９】
本発明の単結晶引上装置によれば、変位規制部材を有する黒鉛ルツボが設けられているので、分割部材の半径方向外方への変位を規制し、ＣＯガスの通り道である分割部の隙間が大きくなることを防止され、石英ルツボから発生したＳｉＯガスと黒鉛ルツボの分割部の特に湾曲部との反応を抑制でき、黒鉛ルツボの湾曲部の薄肉化を防止できるので、黒鉛ルツボの寿命を延ばし、ランニングコストの削減可能であるという効果が得られる。また、黒鉛ルツボの薄肉化による形状の変化に伴石英ルツボの変形が抑制できるので、石英ルツボ内の半導体融液が流出する可能性が低減されているという効果が得られる。さらに、石英ルツボが変形した部分は半導体融液に流れ（乱流）が生じて半導体の単結晶化率が低下するが、そのような変形が抑制されるので、単結晶化率が高いインゴットの製造が可能であるという効果が得られる。
【００４０】
本発明の単結晶引上装置によれば、従来の黒鉛ルツボと黒鉛ルツボ支持台にそれぞれテ−パ部およびテ−パ受け部を設けて分割部材の半径方向外方への変位を規制しているので、上記の単結晶引上装置と同様の効果が得られる。
【図面の簡単な説明】
【図１】（ａ）は本発明に係る第一の実施形態の単結晶引上装置用黒鉛ルツボの平面図、（ｂ）は（ａ）のＡ−Ａ線断面図である。
【図２】図１（ｂ）におけるＰの拡大図である。
【図３】本発明に係る第二の実施形態の単結晶引上装置用黒鉛ルツボの図１（ｂ）におけるＰと同等な部位の拡大図である。
【図４】本発明に係る第三の実施形態の単結晶引上装置における黒鉛ルツボ近傍の該黒鉛ルツボの中心を通る垂直面から視た断面図である。
【図５】ＣＭＣＺ法を用いたシリコンの単結晶引上装置の一例を示す断面図である。
【図６】（ａ）は従来の単結晶引上装置のルツボ構造の平面図、（ｂ）は（ａ）のＸ−Ｘ線断面図である。
【符号の説明】
１単結晶引上装置
１１石英ルツボ
１４ａフランジ部（黒鉛ルツボ支持台）
１５単結晶引上装置用黒鉛ルツボ（黒鉛ルツボ）
１６ａ、１６ｂ、１６ｃ分割部
１７ａ、１７ｂ、１７ｃ湾曲部
２１半導体融液
３１単結晶引上装置用黒鉛ルツボ（黒鉛ルツボ）
３２底部（変位規制部材）
３３側部
３３ａ、３３ｂ、３３ｃ分割部材
３４段部（係合部）
３５つば部（係合受け部）
３６溝部
３７凸部
４０ａ、４０ｂテ−パ部
４１テ−パ受け部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a graphite crucible for a single crystal pulling apparatus and a single crystal pulling apparatus for supporting a quartz crucible for storing a semiconductor melt.
[0002]
[Prior art]
Conventionally, the CZ method is known as one of methods for growing a semiconductor single crystal such as silicon (Si) or gallium arsenide (GaAs).
This CZ method is characterized by the fact that a single crystal having a large diameter and high purity can be easily obtained with no dislocations or very few lattice defects. is there.
[0003]
In recent years, the CZ method has been variously improved and put into practical use in accordance with the demand for increasing the diameter of single crystals, increasing the purity, and homogenizing oxygen concentration and impurity concentration.
As an improved version of the CZ method, a continuous charge type magnetic field application CZ method (hereinafter abbreviated as CMCZ method) using a so-called double crucible has been proposed. In this method, by applying a magnetic field to the semiconductor melt in the crucible from the outside, the convection in the semiconductor melt is suppressed, and a single crystal having a high controllability of oxygen concentration and a high single crystallization rate is grown. It has a feature that a long semiconductor single crystal can be easily obtained by continuously supplying raw materials between an outer crucible and an inner crucible. Therefore, it is said to be one of the most excellent methods for obtaining a large-diameter and long semiconductor single crystal.
[0004]
FIG. 5 shows an example of a silicon single crystal pulling apparatus using the CMCZ method described in JP-A-4-305091. In the single crystal pulling apparatus 1, a double crucible (quartz crucible) 3, a heater 4, and a raw material supply pipe 5 are arranged in a chamber 2 that is a hollow airtight container, and a magnet 6 is arranged outside the chamber 2. Has been.
The present invention to be described later is not limited to a single crystal pulling apparatus based on the CMCZ method. For example, a single crystal pulling apparatus based on a continuous charge type CZ method (CCZ method) without applying a magnetic field, The present invention can also be applied to a single crystal pulling apparatus provided with one crucible instead of a crucible.
[0005]
The double crucible 3 includes a substantially hemispherical quartz (SiO ₂ ) outer crucible (quartz crucible described later) 11 and quartz (SiO ₂ ) which is a cylindrical partition provided in the outer crucible 11. The inner crucible 12 is formed, and the side wall of the inner crucible 12 communicates between the inner crucible 12 and the outer crucible 11 (raw material melting region) and the inner side of the inner crucible 12 (crystal growth region). A plurality of communication holes 13 are formed.
[0006]
The double crucible 3 is accommodated and placed in a graphite crucible (susceptor) 15 on a shaft 14 that is vertically installed at the center lower part of the chamber 2. The double crucible 3 is placed on a horizontal plane around the axis of the shaft 14. It is configured to rotate at a predetermined angular velocity. In the double crucible 3, a semiconductor melt (heated and melted raw material of a semiconductor single crystal) 21 is stored.
As shown in FIG. 6, the graphite crucible 15 is composed of three divided members 15a, 15b, 15c divided along the radial dividing line, and the shafts are formed on the bottom surfaces of the divided members 15a, 15b, 15c. Recesses 20a and 20b (recesses formed in the dividing member 15c are not shown) into which 14 (see FIG. 5) flanges 14a are fitted are formed. The reason why the graphite crucible 15 is divided in the radial direction is to release thermal stress exerted on the graphite crucible 15 and prevent cracking.
[0007]
The substantially cylindrical heater 4 heats and melts a semiconductor raw material in a crucible and keeps the generated semiconductor melt 21, and a resistance heater is usually used. A raw material supply pipe 5 serving as a raw material supply means continuously feeds a predetermined amount of the semiconductor raw material 10 onto the surface of the semiconductor melt 21 between the outer crucible 11 and the inner crucible 12 from its lower end opening. .
[0008]
As the raw material 10 supplied from the raw material supply pipe 5, for example, a polycrystalline silicon ingot is crushed with a crusher or the like into flakes, or precipitated from a gaseous raw material by a pyrolysis method. Polycrystalline silicon granules are preferably used, and if necessary, an additive called a dopant such as boron (B) (when making a p-type silicon single crystal) or phosphorus (P) (when making an n-type silicon single crystal) Additional elements are supplied.
The same applies to gallium arsenide (GaAs). In this case, the additive element is zinc (Zn) or silicon (Si).
[0009]
By the single crystal pulling apparatus 1, the seed crystal 25 is suspended from the pulling shaft 24 disposed above and on the axis of the inner crucible 12 via a chuck (not shown), and the pulling shaft 24 is rotated around its axis. The semiconductor single crystal 26 is grown using the seed crystal 25 as a nucleus above the semiconductor melt 21.
[0010]
By the way, in the above-described single crystal pulling apparatus, as described in JP-A-63-303894, a polycrystalline raw material such as a polycrystalline silicon lump is previously placed in the outer crucible 11 in a pre-process for growing a single crystal. Is melted to store the semiconductor melt 21, and the inner crucible 12 disposed above the outer crucible 11 is placed in the outer crucible 11 to form the double crucible 3.
[0011]
The double crucible 3 is formed after melting the polycrystalline raw material in this way because the raw material in the outer crucible 11 is grown by the single crystal by the heater 4 in order to completely melt the polycrystalline raw material and obtain the semiconductor melt 21. This is because the inner crucible 12 is preliminarily formed in the outer crucible 11 at this time, so that a large thermal deformation occurs in the inner crucible 12.
[0012]
Therefore, after the raw material is completely melted, the inner crucible 12 is formed on the outer crucible 11 after the heating by the heater 4 is weakened to some extent, thereby avoiding high temperature heating during initial raw material melting and holding and suppressing deformation of the inner crucible 12. is doing.
[0013]
Further, the communication hole 13 formed in the inner crucible 12 is set to have a certain opening area or less so that the semiconductor melt 21 flows only from the outer crucible 11 side into the inner crucible 12 when the raw material is supplied. This is because, when the phenomenon that the semiconductor melt 21 returns from the crystal growth region to the raw material melting region by convection occurs, it becomes difficult to control the impurity concentration, the melt temperature, and the like in the single crystal growth.
[0014]
[Problems to be solved by the invention]
However, as shown in FIG. 6, the crucible structure is a structure in which the quartz crucible 11 is simply accommodated in a graphite crucible 15 having a divided structure, so that the gas (types) generated from the quartz crucible 11 as the single crystal production progresses. SiO) and the reaction between the bent portions 17a, 17b, and 17c (parts surrounded by a one-dot chain line in FIG. 6) in the vicinity of the dividing line of the graphite crucible 15 (hereinafter referred to as the dividing portions 16a, 16b, and 16c). Thus, this part is lost and thinned. If the thickness of the defective portion becomes below a specified value due to this thinning, the entire graphite crucible 15 must be replaced with a new one. As a result, the life of the graphite crucible 15 is shortened, the replacement frequency is increased, and as a result, the running cost is increased.
[0015]
Here, the cause that the division parts 16a, 16b, and 16c of the graphite crucible 15 are easily lost is estimated as follows.
That is, first, it is presumed that the SiO gas generated from the quartz crucible 11 reacts with the graphite crucible 15 to cause a reaction in which C is separated from the graphite crucible 15 as CO gas (see the following reaction formula).
SiO + 2C → SiC + CO ↑
Then, due to the quartz crucible 11 being exposed to a high temperature atmosphere during the semiconductor single crystal growth step, the quartz crucible 11 is deformed and is in close contact with the graphite crucible 15, and the SiO gas path is divided into the divided portions 16 a, 16 b, Concentrate on 16c. In the vicinity of the divided portions 16a, 16b, and 16c, the generated CO gas easily moves out of the graphite crucible 15 through the divided portions 16a, 16b, and 16c, so that the CO gas concentration does not easily increase. The reaction of is promoted.
Further, among the divided portions 16a, 16b, and 16c, the curved portions 17a, 17b, and 17c are particularly easily lost for the following reasons. In the furnace, the temperature distribution in the single crystal growth axis direction becomes higher at the lower side and at the outer side in the radial direction, and the reaction is more likely to proceed. On the other hand, since the graphite crucible 15 is placed on the flange 14a, the CO gas hardly escapes from the bottom surface of the graphite crucible 15, so that the reaction does not proceed easily. Thus, the curved portions 17a, 17b, and 17c located in the lower portion near the bottom surface are the portions that are most easily lost.
When the quartz crucible 11 is further deformed and enlarged in a state of being in close contact with the graphite crucible 15, the divided members 15a, 15b, 15 are displaced outward in the radial direction, and the divided portions 16a, 16b, 16c that are passages of CO gas. The gap becomes larger and the above reaction is further promoted.
[0016]
Further, if the defect promotion of the divided portions 16a, 16b, and 16c of the graphite crucible 15 is left as it is, the quartz crucible 11 is also deformed and thinned as the shape of the graphite crucible 15 is reduced. There is also a problem that the possibility of the semiconductor melt in the quartz crucible 11 flowing out increases.
In addition, since the curvature of the deformed portion of the quartz crucible 11 is small, a flow (turbulent flow) is likely to occur in the semiconductor melt in the quartz crucible 11, and as a result, the single crystallization rate of the semiconductor decreases. There is also.
[0017]
The present invention has been made in view of the circumstances described above, and the reaction between the SiO gas generated from the quartz crucible and the graphite crucible is suppressed, thereby extending the life of the graphite crucible and reducing the running cost. An object of the present invention is to provide a graphite crucible for a single crystal pulling apparatus and a single crystal pulling apparatus that can improve the single crystallization rate.
[0018]
[Means for Solving the Problems]
In order to achieve the above object, the present invention employs the following configuration.
A graphite crucible for a single crystal pulling apparatus according to the present invention is a graphite crucible for a single crystal pulling apparatus for supporting a quartz crucible for storing a semiconductor melt, wherein the graphite crucible is divided along a dividing line in the radial direction. It is characterized by comprising a plurality of divided members and a displacement restricting member for restricting the radially outward displacement of the divided members. This graphite crucible for a single crystal pulling apparatus is provided with a displacement restricting member, so that the displacement of the dividing member in the radially outward direction is restricted, and the gap between the dividing portions is prevented from becoming large. In addition, since the displacement regulating member is provided, it is possible to prevent the positional deviation of the divided members.
[0019]
Graphite crucible for single crystal pulling apparatus of the present invention, the graphite crucible for the above single crystal pulling apparatus, the graphite crucible is composed of a bottom and sides, the side portion is from the plurality of divided members, The bottom portion is the displacement regulating member, and an engaging portion is formed along a circumferential direction at a lower end portion of the plurality of divided members, and is engaged with the engaging portion along a circumferential direction at a peripheral edge portion of the displacement regulating member. An engagement receiving portion is formed. In this graphite crucible for a single crystal pulling apparatus, the engagement member provided on the displacement regulating member that forms the bottom part is engaged with the engagement part provided on the division member, so that the radial direction of the division member is achieved. The outward displacement can be prevented and the gap between the divided portions is prevented from becoming large.
[0020]
The graphite crucible for a single crystal pulling apparatus according to the present invention is the above-described graphite crucible for a single crystal pulling apparatus, wherein the engaging portion is a step formed with a flat surface, and the engagement receiving portion is the step. It is a collar part formed with the flat surface which contact | abuts to a part from upper direction, It is characterized by the above-mentioned. In this graphite crucible for a single crystal pulling apparatus, when a force that expands the vicinity of the opening of the graphite crucible is applied as the quartz crucible is deformed, the bottom flange presses down the stepped portion of the dividing member, thereby dividing the graphite crucible. The displacement of the member can be regulated. Therefore, it is possible to prevent the gap between the divided portions from increasing.
[0021]
The graphite crucible for a single crystal pulling apparatus according to the present invention is the above-described graphite crucible for a single crystal pulling apparatus, wherein a groove portion is formed in one of the stepped portion and the flange portion, and the other is engaged with the groove portion. A convex portion is formed. In this graphite crucible for a single crystal pulling apparatus, since the bottom portion and the divided member are engaged by the groove portion and the convex portion, the displacement of the divided member in a wide range other than the vertical direction can be restricted. Therefore, it is possible to prevent the gap between the divided portions from increasing.
[0022]
A single crystal pulling apparatus according to the present invention includes the graphite crucible for a single crystal pulling apparatus described above . Since this single crystal pulling apparatus is provided with a graphite crucible having a displacement regulating member, the displacement of the dividing member in the radially outward direction is restricted, and the gap of the dividing portion that is the passage of CO gas becomes large. Can prevent the reaction between the SiO gas generated from the quartz crucible and the bent portion of the graphite crucible, and in particular, the thickness of the bent portion of the graphite crucible can be prevented, thereby extending the life of the graphite crucible and reducing the running cost. Can be reduced. Further, since the deformation of the quartz crucible accompanying the change in shape due to the thinning of the graphite crucible can be suppressed, the possibility of the semiconductor melt flowing out in the quartz crucible is reduced. Furthermore, the portion where the quartz crucible is deformed causes a flow (turbulent flow) in the semiconductor melt and decreases the single crystallization rate of the semiconductor, but since such deformation is suppressed, an ingot with a high single crystallization rate is obtained. Manufacturing is possible.
[0023]
The single crystal pulling apparatus of the present invention is the single crystal pulling apparatus provided with a graphite crucible for supporting a quartz crucible for storing a semiconductor melt and a graphite crucible support for supporting the graphite crucible from below. The crucible is composed of a plurality of divided members divided along a dividing line in the radial direction, and a taper portion extending in the circumferential direction is provided on the lower peripheral edge of the outer side of the plurality of divided members. A taper receiving portion for supporting the plurality of divided members is formed on the periphery of the upper surface along the circumferential direction so as to contact the taper portion. This single crystal pulling apparatus is provided with a taper portion and a taper receiving portion on a conventional graphite crucible and a graphite crucible support base, respectively, thereby restricting the radially outward displacement of the divided members and The gap between the divided portions, which are gas passages, is prevented from becoming large, and the reaction between the SiO gas generated from the quartz crucible and the graphite crucible is suppressed.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of a graphite crucible for a single crystal pulling apparatus and a single crystal pulling apparatus according to the present invention will be described with reference to the drawings.
5 and 6 are denoted by the same reference numerals, and the description thereof is omitted.
[0025]
First, a first embodiment will be described with reference to FIG. 1 and FIG.
A graphite crucible 31 for a single crystal pulling apparatus of the present embodiment (hereinafter simply referred to as a graphite crucible 31) is composed of a bottom 32 and a side 33, and the side 33 is divided into three divided members 33a, 33b, 33c. The bottom portion 32 is a displacement restricting member 32, and step portions (engaging portions) 34, 34 formed by flat surfaces along the circumferential direction at the lower end portions of the three divided members 33a, 33b, 33c, respectively. 34, and on the other hand, a flange portion (engagement receiving portion) 35 formed along a peripheral surface of the displacement regulating member 32 along the circumferential direction and a flat surface that comes into contact with the stepped portions 34, 34, 34 from above. 35, 35 are formed.
[0026]
In this graphite crucible 31, when the opening of the quartz crucible 11 is deformed and expanded in diameter, the upper portions of the divided members 33a, 33b, 33c receive a force radially outward, and the step portions 34, 34, 34 2 is pressed from above by the flange portions 35, 35, 35 of the displacement restricting member 32 when receiving a force as indicated by the arrow in FIG. Therefore, since the dividing members 33a, 33b, and 33c cannot be displaced radially outward, the gaps between the dividing portions 16a, 16b, and 16c that are the passages of the CO gas are prevented from increasing, and the SiO gas generated from the quartz crucible 11 is prevented. Reaction between the split portions 16a, 16b, and 16c of the graphite crucible 31 and particularly the curved portions 17a, 17b, and 17c.
[0027]
Further, since the displacement regulating member 32 can prevent the positional deviation of the divided members 33a, 33b, and 33c, it is also possible to prevent an increase in the gap between the divided parts 16a, 16b, and 16c due to the positional deviation.
[0028]
Therefore, since the thinning of the curved portions 17a, 17b, and 17c of the divided portions 16a, 16b, and 16c accompanying this reaction is suppressed, the life of the graphite crucible 31 is extended, and the running cost can be reduced.
Further, the quartz crucible 11 is also prevented from being deformed and thinned with the change in shape of the divided portions 16a, 16b, 16c of the graphite crucible 31 due to the thinning of the curved portions 17a, 17b, 17c. Therefore, the possibility that the semiconductor melt in the quartz crucible 11 flows out can be reduced.
Furthermore, although the portion where the quartz crucible 11 is deformed flows in the semiconductor melt (turbulent flow) and the single crystallization rate of the semiconductor decreases, such deformation is suppressed, so the single crystallization rate is improved. To do.
[0029]
Next, a second embodiment will be described with reference to FIG.
Constituent elements equivalent to those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.
In this embodiment, as shown in FIG. 3, groove portions 36, 36, 36 are formed in the step portions 34, 34, 34 of the divided members 33 a, 33 b, 33 c in the first embodiment, and the displacement restricting member 32 is formed. A difference from the first embodiment is that convex portions 37, 37, 37 that engage with the groove portions 36, 36, 36 are formed on the flange portions 35, 35, 35.
[0030]
In this case, even if the dividing members 33a, 33b, and 33c receive the force shown by the arrow in FIG. 3, the grooves 36, 36, and 36 of the dividing members 33a, 33b, and 33c are the convex portions 37 and 37 of the displacement regulating member 32. , 37 cannot be displaced. Therefore, the gaps between the divided portions 16a, 16b, and 16c that are the passages of the CO gas are prevented from becoming large, and the reaction between the SiO gas generated from the quartz crucible 11 and the graphite crucible 31 is suppressed.
[0031]
Next, a third embodiment will be described with reference to FIG.
Constituent elements equivalent to those in the first and second embodiments described above are denoted by the same reference numerals and description thereof is omitted.
In this single crystal pulling apparatus, a graphite crucible 15 composed of three divided members 15a and 15b (divided member 15c is not shown) divided along a dividing line in the radial direction and graphite supporting the graphite crucible 15 from below. In the single crystal pulling apparatus provided with a crucible support base (a component equivalent to the flange portion in FIG. 6) 14a, the lower peripheral edge portion outside the three divided members 15a, 15b, 15c is a tape extending along the circumferential direction. The taper portions 40a, 40b, and 40c (the taper portion 40c is not shown) are provided, and are attached to the taper portion 40a, 40b, and 40c along the circumferential direction at the upper peripheral edge of the graphite crucible support base 14a. A taper receiving portion 41 that supports the three divided members 15a, 15b, and 15c is formed. Here, the outer bottom surface portions 42a, 42b, 42c (the outer bottom surface portion 42c is not shown) of the three divided members 15a, 15b, 15c are configured not to contact the upper surface portion 14b of the graphite crucible support base 14a. The two divided members 15a, 15b and 15c are supported only by the taper receiving portion 41 of the graphite crucible support base 14a.
[0032]
In this embodiment, the taper portions 40a, 40b, and 40c receive the force of the component in the direction perpendicular to the taper portions 40a, 40b, and 40c of the weight of the split member itself, and thus the three split members 15a. , 15b, 15c cannot be displaced radially outward. In this case, the three divided members 15a, 15b, and 15c are supported by only the taper receiving portion 41 of the graphite crucible support base 14a, thereby effectively restricting the displacement. For this reason, the gap between the dividing portions 16a, 16b, and 16c (not shown in FIG. 4), which is a passage for CO gas, is prevented from increasing, so that the reaction between the SiO gas generated from the quartz crucible 11 and the graphite crucible 15 is suppressed. Is done.
[0033]
The graphite crucible 15 or the graphite crucible 31 described in the above embodiment is not limited to the one divided into three, and may be divided into other numbers.
[0034]
【The invention's effect】
As described above in detail, the present invention has the following effects.
[0035]
According to the graphite crucible for a single crystal pulling apparatus of the present invention , since the displacement restricting member is provided, it is possible to prevent the gap between the dividing portions from becoming large by restricting the radially outward displacement of the dividing member. Therefore, the reaction between the SiO gas generated from the quartz crucible and the graphite crucible can be suppressed, and the thinning of the graphite crucible can be prevented, so that the life of the graphite crucible can be extended and the running cost can be reduced. In addition, since the deformation of the quartz crucible can be suppressed as the shape of the graphite crucible is changed due to the thinning of the graphite crucible, it is possible to reduce the possibility that the semiconductor melt in the quartz crucible flows out. Furthermore, the portion where the quartz crucible is deformed flows in the semiconductor melt (turbulent flow) and the semiconductor single crystallization rate decreases, but such deformation is suppressed, so that the single crystallization rate is improved. The effect of being able to be obtained. In addition, an effect is obtained that it is possible to prevent an increase in the gap between the divided portions due to the displacement of the divided members.
[0036]
According to a graphite crucible for single crystal pulling apparatus of the present invention, by a simple structure of engaging the engagement receiving portion provided on the displacement regulating member forming the bottom engaging portion provided in the divided members, the The effect similar to the effect can be obtained.
[0037]
According to the graphite crucible for a single crystal pulling apparatus of the present invention , when a force for expanding the vicinity of the opening of the graphite crucible is applied in accordance with the deformation of the quartz crucible, the bottom flange portion presses the stepped portion of the dividing member. Thereby, the displacement of a division member can be controlled. Therefore, the effect that it can prevent that the clearance gap between division parts becomes large is acquired.
[0038]
According to the graphite crucible for a single crystal pulling apparatus of the present invention , since the bottom portion and the divided member are engaged by the groove portion and the convex portion, the displacement of the divided member in a wide range direction except the vertical direction is regulated. Can do. Therefore, the effect that it can prevent that the clearance gap between division parts becomes large is acquired.
[0039]
According to the single crystal pulling apparatus of the present invention, since the graphite crucible having the displacement restricting member is provided, the displacement of the dividing member in the radially outward direction is restricted, and the gap of the dividing portion which is the passage of CO gas. Is prevented, and the reaction between the SiO gas generated from the quartz crucible and the bent portion of the graphite crucible, in particular, the bent portion can be suppressed, and thinning of the bent portion of the graphite crucible can be prevented. The effect of extending the running cost can be obtained. In addition, since the deformation of the quartz crucible can be suppressed as the shape of the graphite crucible is reduced, the possibility that the semiconductor melt in the quartz crucible flows out is reduced. Furthermore, the portion where the quartz crucible is deformed causes a flow (turbulent flow) in the semiconductor melt and decreases the single crystallization rate of the semiconductor, but since such deformation is suppressed, an ingot with a high single crystallization rate is obtained. The effect that manufacture is possible is acquired.
[0040]
According to the single crystal pulling apparatus of the present invention , a conventional graphite crucible and a graphite crucible support base are provided with a taper portion and a taper receiving portion, respectively, to restrict displacement of the divided member in the radially outward direction. Therefore, the same effect as the above single crystal pulling apparatus can be obtained.
[Brief description of the drawings]
FIG. 1A is a plan view of a graphite crucible for a single crystal pulling apparatus according to a first embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line AA in FIG.
FIG. 2 is an enlarged view of P in FIG.
FIG. 3 is an enlarged view of a portion equivalent to P in FIG. 1B of a graphite crucible for a single crystal pulling apparatus according to a second embodiment of the present invention.
FIG. 4 is a cross-sectional view seen from a vertical plane passing through the center of the graphite crucible in the vicinity of the graphite crucible in the single crystal pulling apparatus according to the third embodiment of the present invention.
FIG. 5 is a cross-sectional view showing an example of a silicon single crystal pulling apparatus using a CMCZ method.
6A is a plan view of a crucible structure of a conventional single crystal pulling apparatus, and FIG. 6B is a sectional view taken along line XX of FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Single crystal pulling apparatus 11 Quartz crucible 14a Flange part (graphite crucible support stand)
15 Graphite crucible for single crystal pulling equipment (graphite crucible)
16a, 16b, 16c Dividing parts 17a, 17b, 17c Bending part 21 Semiconductor melt 31 Graphite crucible for single crystal pulling device (graphite crucible)
32 Bottom (displacement regulating member)
33 Side parts 33a, 33b, 33c Dividing member 34 Step part (engagement part)
35 collar (engagement receiving part)
36 groove part 37 convex part 40a, 40b taper part 41 taper receiving part

Claims

In a graphite crucible for a single crystal pulling apparatus for supporting a quartz crucible for storing a semiconductor melt,
The graphite crucible includes a plurality of divided members divided along a dividing line in the radial direction and a displacement regulating member for regulating displacement of the divided member in the radially outward direction,
The graphite crucible is composed of a bottom portion and a side portion, the side portion is composed of the plurality of divided members, the bottom portion is the displacement regulating member, and is engaged with a lower end portion of the plurality of divided members along a circumferential direction. A portion is formed, and an engagement receiving portion that is engaged with the engagement portion is formed along the circumferential direction of the peripheral portion of the displacement regulating member,
The engaging portion is a step portion formed with a flat surface, and the engagement receiving portion is a collar portion formed with a flat surface that comes into contact with the step portion from above,
A graphite crucible for a single crystal pulling apparatus, wherein a groove portion is formed in one of the stepped portion and the flange portion, and a convex portion engaging with the groove portion is formed in the other.

A single crystal pulling apparatus comprising the graphite crucible for a single crystal pulling apparatus according to claim 1.