JP2962976B2 - Quartz glass crucible - Google Patents
Quartz glass crucibleInfo
- Publication number
- JP2962976B2 JP2962976B2 JP21686493A JP21686493A JP2962976B2 JP 2962976 B2 JP2962976 B2 JP 2962976B2 JP 21686493 A JP21686493 A JP 21686493A JP 21686493 A JP21686493 A JP 21686493A JP 2962976 B2 JP2962976 B2 JP 2962976B2
- Authority
- JP
- Japan
- Prior art keywords
- quartz glass
- crucible
- glass crucible
- grinding
- single crystal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Surface Treatment Of Glass (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
Description
【0001】[0001]
【産業上の利用分野】この発明は、黒鉛ルツボと接触す
るSi単結晶引上げ用の石英ガラスルツボに関するもの
である。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a quartz glass crucible for pulling a Si single crystal in contact with a graphite crucible.
【0002】[0002]
【従来の技術】石英ガラスルツボは黒鉛ルツボの内側に
配置され、Si単結晶の引上げに用いられる。2. Description of the Related Art A quartz glass crucible is arranged inside a graphite crucible and used for pulling a Si single crystal.
【0003】石英ガラスルツボは石英粉を成形溶融後
に、ルツボ外面に付着した未溶融粉を一部除去すること
によって製造される。従来、外面に付着した未溶融粉
は、必要に応じて石英ガラスルツボの外面全体を高圧液
体でブラスティングするか、又はルツボの円筒部(スト
レート部)外面のみを旋盤等で加工することによって除
去している。[0003] Quartz glass crucibles are produced by molding and melting quartz powder and then removing part of the unmelted powder attached to the outer surface of the crucible. Conventionally, unmelted powder adhering to the outer surface is removed by blasting the entire outer surface of the quartz glass crucible with high-pressure liquid as necessary, or by processing only the outer surface of the cylindrical portion (straight portion) of the crucible with a lathe or the like. doing.
【0004】[0004]
【発明が解決しようとする課題】しかしながら、前者の
方法では、石英ガラスルツボ外面の中心線平均粗さが1
00μm以上になってしまい、寸法精度も充分ではなか
った。他方、黒鉛ルツボは高精度機械加工によって表面
の仕上げが行われる。このような表面粗さ及び寸法精度
の違いによって、両者の接合面には不均一な隙間が生じ
ることが多かった。そして、Si単結晶を引上げる際
に、高温になって軟化した石英ガラスルツボが変形し、
溶融Si液面に振動が生じることがあった。その場合に
は、引きあげたSi単結晶の特性に悪影響が生じ、歩留
が低下していた。However, in the former method, the center line average roughness of the outer surface of the quartz glass crucible is 1%.
Thus, the dimensional accuracy was not sufficient. On the other hand, the surface of the graphite crucible is finished by high precision machining. Due to such differences in surface roughness and dimensional accuracy, non-uniform gaps are often generated at the joint surfaces of the two. Then, when pulling the Si single crystal, the quartz glass crucible softened due to high temperature is deformed,
Vibration sometimes occurred on the liquid surface of the molten Si. In that case, the characteristics of the pulled Si single crystal were adversely affected, and the yield was reduced.
【0005】また、後者の方法では、ストレート部(円
筒部)の寸法精度は充分であるが、それ以外の部分でカ
ーボンルツボとの間にやはり隙間が生じ、同様の液面振
動が発生する場合があった。また、ストレート部とそれ
以外の部分の面粗さの差が大きいため、加熱時に両方の
部分での熱線透過率が異なって溶融Siの温度制御に悪
影響を与えていた。In the latter method, the dimensional accuracy of the straight portion (cylindrical portion) is sufficient, but a gap is also formed between the straight portion and the carbon crucible in other portions, and similar liquid level vibration occurs. was there. Further, since the difference in surface roughness between the straight portion and the other portion is large, the heat ray transmittance in both portions is different during heating, which adversely affects the temperature control of the molten Si.
【0006】いずれにせよ、特に大口径の石英ガラスル
ツボにおいて前述の問題が生じ易く、Si単結晶引上げ
の歩留り(単結晶化率)が低下していた。In any case, the above-mentioned problem tends to occur particularly in a large-diameter quartz glass crucible, and the yield (single crystallization ratio) of pulling a Si single crystal has been lowered.
【0007】本発明は、前述のような従来技術の問題点
を解消して、Si単結晶引上げの歩留り(単結晶化率)
を向上させることが可能な石英ガラスルツボを提供する
ことを目的としている。The present invention solves the above-mentioned problems of the prior art, and improves the yield of single crystal pulling (single crystallization ratio).
It is an object of the present invention to provide a quartz glass crucible capable of improving the quality.
【0008】[0008]
【課題を解決するための手段】この発明は黒鉛ルツボと
接触するSi単結晶引上げ用の石英ガラスルツボの少な
くとも底部が不透明であり、かつ該石英ガラスルツボの
外面全体の中心線平均粗さRaが0.1μm〜50μm
であることを特徴とする石英ガラスルツボを要旨として
いる。According to the present invention, at least the bottom of a quartz glass crucible for pulling a Si single crystal in contact with a graphite crucible is opaque, and the center line average roughness Ra of the entire outer surface of the quartz glass crucible is low. 0.1 μm to 50 μm
The gist of the present invention is a quartz glass crucible.
【0009】[0009]
【実施例】以下、図面を参照して本発明の好適な実施例
を説明する。図1は本発明による石英ガラスルツボを製
造するための研削工程を示す図、図2は図1の研削砥石
を示す断面図である。なお、研削を広義に解釈し、研磨
も研削に含まれるものとする。Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a view showing a grinding process for manufacturing a quartz glass crucible according to the present invention, and FIG. 2 is a sectional view showing the grinding wheel of FIG. Note that grinding is interpreted in a broad sense, and polishing is also included in grinding.
【0010】図1の石英ガラスルツボは、通常の回転溶
融法で石英粉を溶融成形したものである。これにより、
全体的に微小な気泡を多数含む不透明な石英ガラスルツ
ボが形成される。なお、この石英ガラスルツボの内面に
は透明層が形成される。また、その外面には未溶融石英
粉が付着している。そこで、図1に示す研削装置10に
よってルツボの外面全体を研削する。The quartz glass crucible shown in FIG. 1 is obtained by melting and molding quartz powder by an ordinary rotary melting method. This allows
An opaque quartz glass crucible containing a large number of small bubbles is formed as a whole. A transparent layer is formed on the inner surface of the quartz glass crucible. Unmelted quartz powder adheres to the outer surface. Therefore, the entire outer surface of the crucible is ground by the grinding device 10 shown in FIG.
【0011】研削装置10は、ベース11に設けられた
ディスク型の回転テーブル12を有している。回転テー
ブル12には、その回転軸の延長線上にセンタ押え15
が設けられている。センタ押え15の先端にはルツボ底
部の中央に当接するゴム15aが固定されている。The grinding device 10 has a disk-type rotary table 12 provided on a base 11. The rotary table 12 has a center presser 15 on an extension of its rotary shaft.
Is provided. A rubber 15a that is in contact with the center of the crucible bottom is fixed to the end of the center presser 15.
【0012】センタ押えの中程にはストレート部上方チ
ャック13が固定されている。ストレート部上方チャッ
ク13はルツボの大きさに合わせて径を変えるこが可能
であり、その外端部にはルツボのストレート部内周に当
接するゴム13aが配置されている。A straight portion upper chuck 13 is fixed in the middle of the center retainer. The diameter of the straight portion upper chuck 13 can be changed according to the size of the crucible, and a rubber 13a which is in contact with the inner periphery of the straight portion of the crucible is arranged at the outer end.
【0013】回転テーブル12の上面には、ストレート
部下方チャック14が配置されている。ストレート部下
方チャック14もルツボの大きさに合わせて径を変える
ことが可能であり、その外端部にはルツボのストレート
部内周に当接するゴム14aが配置されている。On the upper surface of the turntable 12, a straight portion lower chuck 14 is disposed. The diameter of the straight portion lower chuck 14 can also be changed in accordance with the size of the crucible, and a rubber 14a that is in contact with the inner periphery of the straight portion of the crucible is disposed at the outer end.
【0014】研削装置10は、砥石回転移動手段21を
備えている。砥石回転移動手段21は高速回転可能なス
ピンドルを有している。スピンドルには研削砥石16を
設定することができる。ヘッド21は、図1の図平面内
で定めた所定経路(A〜E)を速度をかえて移動可能で
ある。経路A,Bはスピンドルを研削速度(低速)で移
動させ、経路C〜Fはスピンドルを早送りで移動させ
る。The grinding device 10 has a grinding wheel rotating / moving means 21. The grindstone rotation moving means 21 has a spindle that can rotate at high speed. A grinding wheel 16 can be set on the spindle. The head 21 can move at different speeds along predetermined paths (A to E) determined in the plane of FIG. Paths A and B move the spindle at the grinding speed (low speed), and paths C to F move the spindle at a rapid traverse.
【0015】好ましい一例を挙げると、研削砥石16
は、カップ形のダイヤモンド砥石で、カップ状の台金1
9とその下部外周に着脱可能に設けられた砥石取付部1
7を有している。台金19はアルミ製であり、砥石取付
部17は樹脂製である。砥石取付部17には砥石本体1
8が取付けられている。砥石本体18は曲率半径がRの
研削面を有している。すなわち、砥石本体18の断面形
状は図2では半円形になっている。また、矢印で示した
ように下方が湾曲した1/4円形でもよい。As a preferred example, a grinding wheel 16
Is a cup-shaped diamond whetstone, cup-shaped base metal 1
9 and a whetstone mounting part 1 detachably provided on the outer periphery of its lower part
7. The base metal 19 is made of aluminum, and the whetstone mounting portion 17 is made of resin. The whetstone body 1 is attached to the whetstone mounting portion 17.
8 are attached. The grindstone main body 18 has a ground surface with a radius of curvature of R. That is, the cross-sectional shape of the grindstone main body 18 is a semicircle in FIG. Further, as shown by an arrow, a downwardly curved quarter circle may be used.
【0016】さて、図1に示した研削装置10を用い
て、ルツボ1を低速で回転させ、一方研削砥石16を高
速回転させつつ経路A,Bを移動させて、ルツボの外面
全体の研削を行った。そして、得られた石英ガラスルツ
ボの外面の中心線平均粗さRaを測定したところ0.1
μm〜50μmの範囲内であった。また、その寸法精度
を調べたところ、外径は設計寸法508mmに対して誤
差が±1mm以内、肉厚は同じく11mmに対して誤差
が±1.5mm以内、外側R形状は508mmに対して
誤差が±1mm以内、高さは356mmに対して誤差が
±2mm以内であった。Now, using the grinding apparatus 10 shown in FIG. 1, the crucible 1 is rotated at a low speed, and the paths A and B are moved while the grinding wheel 16 is rotated at a high speed to grind the entire outer surface of the crucible. went. The center line average roughness Ra of the outer surface of the obtained quartz glass crucible was measured to be 0.1.
It was in the range of μm to 50 μm. When the dimensional accuracy was examined, the outer diameter had an error within ± 1 mm with respect to the design dimension of 508 mm, the wall thickness had an error within ± 1.5 mm with respect to 11 mm, and the outer radius had an error with respect to 508 mm. Was within ± 1 mm and the height was within ± 2 mm with respect to 356 mm.
【0017】この石英ガラスルツボを用いてSi単結晶
の引上げを行い、歩留りを調べた。その結果、従来のル
ツボを用いた場合に較べて歩留りが約5%向上した。Using this quartz glass crucible, a Si single crystal was pulled, and the yield was examined. As a result, the yield was improved by about 5% as compared with the case where the conventional crucible was used.
【0018】以上述べたように、本発明は石英ガラスル
ツボの外面全体を研削して中心線平均粗さを0.1μm
以上50μm以下に調整する構成になっている。ルツボ
外面の中心線平均粗さは、さらに望ましくは10μm以
下に設定し、最適には6μm以下に設定する。As described above, according to the present invention, the entire outer surface of a quartz glass crucible is ground to reduce the center line average roughness to 0.1 μm.
It is configured to be adjusted to not less than 50 μm. The center line average roughness of the crucible outer surface is more desirably set to 10 μm or less, and optimally set to 6 μm or less.
【0019】本発明は、例えば石英ガラスルツボのスト
レート部の上方を不透明石英ガラスとし、底部を含む下
方を透明石英ガラスとしたもの、もしくは、この逆にし
たもの等においても効果を奏するものである。The present invention is also effective when, for example, the upper part of the quartz glass crucible is made of opaque quartz glass above the straight part and the lower part including the bottom part is made of transparent quartz glass or vice versa. .
【0020】[0020]
【発明の効果】本発明の石英ガラスルツボは、黒鉛ルツ
ボと接触するSi単結晶引上げ用の石英ガラスルツボの
少なくとも底部が不透明であり、かつ該石英ガラスルツ
ボの外面全体の中心線平均粗さRaが0.1μm〜50
μmになっているので、従来のルツボに較べて表面粗さ
が改善され寸法精度も向上する。According to the quartz glass crucible of the present invention, at least the bottom of the quartz glass crucible for pulling a Si single crystal in contact with the graphite crucible is opaque, and the center line average roughness Ra of the entire outer surface of the quartz glass crucible is obtained. Is 0.1 μm to 50
Since it is μm, the surface roughness is improved and the dimensional accuracy is improved as compared with the conventional crucible.
【0021】従って、外側に配置する黒鉛ルツボとの接
触状態を良好に保つことができ、ルツボの軟化に起因す
る溶融Si液面の振動を防止できる。また、ストレート
部と底部の面粗さがほぼ同一となって、熱線透過率が等
しくなるので、温度制御の精度を向上させることができ
る。Therefore, it is possible to maintain good contact with the graphite crucible disposed on the outside, and to prevent vibration of the molten Si liquid surface due to softening of the crucible. Further, since the surface roughness of the straight portion and the bottom portion are substantially the same and the heat ray transmittance is equal, the accuracy of temperature control can be improved.
【0022】このため、本発明のガラスルツボを用いる
ことにより、Si単結晶の歩留りを従来のルツボに較べ
て大幅に向上させることができる。Therefore, by using the glass crucible of the present invention, the yield of Si single crystal can be greatly improved as compared with the conventional crucible.
【0023】なお、本発明は前述の実施例に限定されな
い。例えば、研削経路は、図1に示した径路の逆方向で
あってもよい。また石英ガラスルツボの寸法や形状も実
施例におけるものに限らず様々な寸法や形状を採用でき
る。The present invention is not limited to the above embodiment. For example, the grinding path may be in the opposite direction of the path shown in FIG. Also, the size and shape of the quartz glass crucible are not limited to those in the embodiment, and various sizes and shapes can be adopted.
【図1】本発明の石英ガラスルツボを製造する工程を示
す図。FIG. 1 is a diagram showing a process for manufacturing a quartz glass crucible of the present invention.
【図2】図1の研削砥石を示す断面図。FIG. 2 is a sectional view showing the grinding wheel of FIG. 1;
1 石英ガラスルツボ 10 研削装置 11 ベース 12 回転テーブル 13 ストレート部上方チャック 14 ストレート部下方チャック 15 センタ押え 13a,14a,15a ゴム部材 16 研削砥石 17 砥石取付け部材 18 砥石本体 DESCRIPTION OF SYMBOLS 1 Quartz glass crucible 10 Grinding device 11 Base 12 Rotary table 13 Straight part upper chuck 14 Straight part lower chuck 15 Center presser 13a, 14a, 15a Rubber member 16 Grinding grindstone 17 Grinding stone attaching member 18 Grinding stone main body
───────────────────────────────────────────────────── フロントページの続き (72)発明者 高力 一彦 山形県西置賜郡小国町大字小国町378番 地 東芝セラミックス株式会社 小国製 造所内 (56)参考文献 特開 平4−12088(JP,A) 特開 平3−88792(JP,A) 特開 平4−119986(JP,A) 実開 昭62−162267(JP,U) (58)調査した分野(Int.Cl.6,DB名) C30B 1/00 - 27/02 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kazuhiko Takashi 378 Oguni-machi, Oguni-machi, Nishiokitama-gun, Yamagata Prefecture Inside the Oguni Plant, Toshiba Ceramics Corporation (56) References JP-A-4-12088 JP-A-3-88792 (JP, A) JP-A-4-119986 (JP, A) JP-A-62-162267 (JP, U) (58) Fields investigated (Int. Cl. 6 , DB name) C30B 1/00-27/02
Claims (1)
用の石英ガラスルツボの少なくとも底部が不透明であ
り、かつ該石英ガラスルツボの外面全体の中心線平均粗
さRaが0.1μm〜50μmであることを特徴とする
石英ガラスルツボ。1. A quartz glass crucible for pulling a Si single crystal in contact with a graphite crucible has at least a bottom portion that is opaque, and the center line average roughness Ra of the entire outer surface of the quartz glass crucible is 0.1 μm to 50 μm. A quartz glass crucible characterized in that:
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP21686493A JP2962976B2 (en) | 1993-08-10 | 1993-08-10 | Quartz glass crucible |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP21686493A JP2962976B2 (en) | 1993-08-10 | 1993-08-10 | Quartz glass crucible |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0753295A JPH0753295A (en) | 1995-02-28 |
JP2962976B2 true JP2962976B2 (en) | 1999-10-12 |
Family
ID=16695108
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP21686493A Expired - Fee Related JP2962976B2 (en) | 1993-08-10 | 1993-08-10 | Quartz glass crucible |
Country Status (1)
Country | Link |
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JP (1) | JP2962976B2 (en) |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4454059B2 (en) * | 1999-01-29 | 2010-04-21 | 信越石英株式会社 | Large diameter quartz glass crucible for pulling silicon single crystal |
JP4330363B2 (en) | 2003-03-28 | 2009-09-16 | ジャパンスーパークォーツ株式会社 | Quartz glass crucible |
JP5229778B2 (en) * | 2007-09-28 | 2013-07-03 | 株式会社Sumco | Method for producing quartz glass crucible for pulling silicon single crystal |
JP4879220B2 (en) * | 2008-05-28 | 2012-02-22 | ジャパンスーパークォーツ株式会社 | Quartz glass crucible and manufacturing method thereof |
JP5008695B2 (en) * | 2008-06-30 | 2012-08-22 | ジャパンスーパークォーツ株式会社 | Silica glass crucible and silicon single crystal pulling method using quartz glass crucible |
WO2016147824A1 (en) * | 2015-03-17 | 2016-09-22 | 住友電気工業株式会社 | Method for producing silicon carbide single crystal |
CN113348275B (en) | 2018-12-27 | 2024-01-12 | 胜高股份有限公司 | Quartz glass crucible and method for producing silicon single crystal using same |
JP7326030B2 (en) * | 2019-06-04 | 2023-08-15 | モメンティブ・テクノロジーズ・山形株式会社 | Method for manufacturing quartz glass crucible |
-
1993
- 1993-08-10 JP JP21686493A patent/JP2962976B2/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
JPH0753295A (en) | 1995-02-28 |
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