JPH0692276B2 - Quartz crucible for pulling silicon single crystal - Google Patents
Quartz crucible for pulling silicon single crystalInfo
- Publication number
- JPH0692276B2 JPH0692276B2 JP63021845A JP2184588A JPH0692276B2 JP H0692276 B2 JPH0692276 B2 JP H0692276B2 JP 63021845 A JP63021845 A JP 63021845A JP 2184588 A JP2184588 A JP 2184588A JP H0692276 B2 JPH0692276 B2 JP H0692276B2
- Authority
- JP
- Japan
- Prior art keywords
- crucible
- quartz
- bubble content
- quartz crucible
- peripheral side
- 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 - Lifetime
Links
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明は、多結晶シリコンを溶融して単結晶シリコンを
製造する際に用いられる石英ルツボであって、単結晶化
率の良い石英ルツボに関する。Description: TECHNICAL FIELD The present invention relates to a quartz crucible used for manufacturing single crystal silicon by melting polycrystalline silicon, and relates to a quartz crucible having a high single crystallization rate. .
［従来技術と問題点］ 半導体用シリコン単結晶は、現在、主にチョクラルスキ
ー法（CZ法）により製造されている。[Prior Art and Problems] Silicon single crystals for semiconductors are currently manufactured mainly by the Czochralski method (CZ method).
該CZ法では、多結晶シリコンを石英ルツボ内部に充填
し、約1450℃に加熱溶融して該溶融シリコンからシリコ
ン単結晶を引き上げる。この場合、ルツボ壁体（周壁及
び底壁）の内表面付近に気泡が内在すると、上記加熱の
際に内部気泡が熱膨張してルツボ内表面を部分的に剥離
させ、剥離した石英小片が単結晶に混入して単結晶化率
（シリコン多結晶が単結晶になる割合）を低下させる原
因となる。また、剥離した石英小片に含有される不純物
がシリコン単結晶に混入してシリコン純度を低下させる
原因になる。In the CZ method, polycrystalline silicon is filled in a quartz crucible and heated and melted at about 1450 ° C. to pull up a silicon single crystal from the molten silicon. In this case, if air bubbles are present near the inner surface of the crucible wall (peripheral wall and bottom wall), the inner air bubbles are thermally expanded during the above heating to partially exfoliate the inner surface of the crucible, and the exfoliated quartz pieces may be separated. It is mixed in the crystal and causes a decrease in the single crystallization rate (the rate at which the silicon polycrystal becomes a single crystal). In addition, impurities contained in the peeled quartz pieces are mixed into the silicon single crystal, which causes a decrease in silicon purity.
其処で、従来、ルツボ全体の内部気泡を減少することが
試みられ、肉眼では殆ど内部に気泡が観察されない石英
ルツボが開発されている。然し乍ら、この種のルツボ
は、ルツボ壁体全体の平均気泡含有率は小さいものの、
ルツボの内表面付近に微小な気泡（マイクロバブル）が
偏在しており、ルツボの加熱時に、該微小気泡が熱膨張
して前述と同様の問題を生じる。即ち、ルツボ壁体の平
均気泡含有率を単に減少させても従来の問題を解決する
ことは出来ない。Therefore, it has been attempted to reduce air bubbles inside the entire crucible, and a quartz crucible in which almost no air bubbles are observed inside has been developed. However, although this type of crucible has a small average bubble content in the entire crucible wall,
Micro bubbles are unevenly distributed in the vicinity of the inner surface of the crucible, and when the crucible is heated, the micro bubbles thermally expand and cause the same problem as described above. That is, the conventional problems cannot be solved by simply reducing the average bubble content of the crucible wall.
［問題解決に係る知見］ 本発明において、ルツボの内周側部分の気泡含有率に対
する外周側部分の気泡含有率を調整することにより、内
周側部分の気泡膨張が抑制され、従来の問題を克服でき
ることが見出された。具体的には、内周側部分の気泡含
有率を従来のマイクロバブルが残留する程度に維持して
も、外周側部分の気泡含有率を寧ろ此れより大きく調整
することによって単結晶化率の良いルツボを製造できる
ことが見出された。[Knowledge on Problem Solving] In the present invention, by adjusting the bubble content rate of the outer peripheral side portion with respect to the bubble content rate of the inner peripheral side portion of the crucible, the bubble expansion of the inner peripheral side portion is suppressed, and the conventional problem It was found that we could overcome it. Specifically, even if the bubble content rate of the inner peripheral side portion is maintained to the extent that conventional microbubbles remain, by adjusting the bubble content rate of the outer peripheral side portion rather than this, the single crystallization rate of It has been found that a good crucible can be produced.
［発明の構成］ 本発明によれば、原料の石英粉をモールドに充填後、減
圧下で溶融してルツボに成形する際に、減圧時間、溶融
時間および溶融温度を調整することにより製造された石
英ルツボであって、ルツボ壁体の内周側部分の気泡含有
率が0.1〜0.5％であり、外周側部分の気泡含有率が内周
側部分の気泡含有率の２倍以上であることを特徴とする
シリコン単結晶引上げ用石英ルツボが提供される。[Constitution of the Invention] According to the present invention, the quartz powder as a raw material is filled in a mold, and then melted under reduced pressure to form a crucible, which is manufactured by adjusting a reduced pressure time, a melting time and a melting temperature. It is a quartz crucible, and the bubble content rate of the inner peripheral side portion of the crucible wall body is 0.1 to 0.5%, and the bubble content rate of the outer peripheral side portion is more than twice the bubble content rate of the inner peripheral side portion. A characteristic quartz crucible for pulling a silicon single crystal is provided.
本発明において、気泡含有率とは、石英ルツボの一定面
積（w1）に対する気泡占有面積（w2）の比（w2/w1）を
云う。石英ルツボの内表面から外表面に至るルツボ断面
の気泡含有率は、次のように測定できる。石英ルツボか
ら、その内表面と外表面を含む厚さ1.2〜2.0mmの小片を
切り出し、此れを測定試料とし、内表面から外表面に至
る一定面積（w1）において白色に表われる石英の基質部
分に対して黒色に表われる気泡の占有面積部分の合計
（w2）を算出し、測定面積に対する気泡占有面積の比
（w2/w1）を当該領域の気泡含有率とする。In the present invention, the bubble content rate refers to the ratio (w 2 / w 1 ) of the bubble occupied area (w 2 ) to the constant area (w 1 ) of the quartz crucible. The bubble content of the crucible cross section from the inner surface to the outer surface of the quartz crucible can be measured as follows. From the quartz crucible, a small piece with a thickness of 1.2 to 2.0 mm including the inner surface and the outer surface is cut out, and this is used as a measurement sample. Quartz that appears white in a certain area (w 1 ) from the inner surface to the outer surface. The total (w 2 ) of the occupied area of bubbles appearing in black with respect to the substrate portion is calculated, and the ratio of the occupied area of bubbles to the measured area (w 2 / w 1 ) is taken as the bubble content rate of the region.
上記測定の際、既知の画像処理装置を利用することが出
来る。画面上の任意部分の合計面積を自動的に算出する
画像処理装置が知られている。A known image processing device can be used for the above measurement. There is known an image processing apparatus that automatically calculates the total area of an arbitrary portion on the screen.
本発明において、ルツボ壁体の内周側部分とは、ルツボ
壁体の内表面から外表面に至る範囲において、ルツボに
充填される溶融シリコンにより内周面に沿って侵食され
る部分を云う。石英（SiO2）の融点は約1700℃であり、
シリコン（Si）の上記溶融温度に対して約250℃の温度
差を有するが、石英ルツボの内表面は高温により軟化し
ており貯溜する溶融シリコンとの摩擦によって浸食させ
る。浸食される深さは溶融条件によって異なり、一例と
して、肉厚８〜10mm、口径350〜360mm、引上げ時間25〜
30時間の場合、侵食深さは通常約0.5〜0.7mmである。ル
ツボ壁体の外周側部分とは、上記内周側部分より外周面
に至る範囲を云う。In the present invention, the inner peripheral side portion of the crucible wall body refers to a portion that is eroded along the inner peripheral surface by the molten silicon filling the crucible in the range from the inner surface to the outer surface of the crucible wall body. The melting point of quartz (SiO 2 ) is about 1700 ℃,
Although there is a temperature difference of about 250 ° C. with respect to the melting temperature of silicon (Si), the inner surface of the quartz crucible is softened by high temperature and is eroded by friction with the stored molten silicon. The depth of erosion depends on the melting conditions. As an example, the wall thickness is 8-10 mm, the caliber is 350-360 mm, and the pulling time is 25-
At 30 hours, the erosion depth is usually about 0.5-0.7 mm. The outer peripheral side portion of the crucible wall body refers to the range from the inner peripheral side portion to the outer peripheral surface.
本発明のルツボは、上記内周側部分の気泡含有率が0.5
％以下であって外周側部分の気泡含有率が0.5％より大
きい。ルツボ壁体の気泡含有率をこのように調整するこ
とにより、ルツボ加熱時に、内周側部分の気泡が気泡含
有率の大きい外周側気泡に吸収され、この結果、内周側
の気泡の熱膨張が抑制されるので、ルツボ内周面の部分
的な剥離を生じない。内周側部分の気泡含有率が0.5％
より大きいと、外周側部分の気泡含有率をこれより大き
くしても、上記ルツボ内周面の剥離を十分に防止出来な
い。また、外周側部分の気泡含有率と内周側部分の気泡
含有率の差は大きいほど好ましく、外周側部分の気泡含
有率は内周側部分の気泡含有率に対して２倍以上が適当
である。従って、好ましい気泡含有率は、内周側部分が
0.1〜0.5％、外周側部分が1.0％以上である。The crucible of the present invention has a bubble content rate of 0.5 on the inner peripheral side.
% Or less, and the bubble content rate on the outer peripheral side is greater than 0.5%. By adjusting the bubble content of the crucible wall in this way, when the crucible is heated, the bubbles on the inner peripheral side are absorbed by the bubbles on the outer peripheral side having a large bubble content, and as a result, the thermal expansion of the bubbles on the inner peripheral side occurs. Is suppressed, the partial peeling of the inner peripheral surface of the crucible does not occur. The air bubble content in the inner circumference is 0.5%
If it is larger, even if the bubble content rate of the outer peripheral side portion is larger than this, peeling of the inner peripheral surface of the crucible cannot be sufficiently prevented. Further, the larger the difference between the bubble content rate of the outer peripheral side portion and the bubble content rate of the inner peripheral side portion is, the more preferable, and the bubble content rate of the outer peripheral side portion is appropriately twice or more the bubble content rate of the inner peripheral side portion. is there. Therefore, the preferable bubble content rate is as follows:
0.1 to 0.5%, and the outer peripheral portion is 1.0% or more.
本発明に係る石英ルツボの模式的な部分断面図およびそ
の内部気泡分布グラフの一例を第１図に示す。図示する
例において、石英ルツボの内周側部分10には気泡が殆ど
観察されず、壁体内部中央部20から外周面側部分30の範
囲に気泡11が分散している。内周面側10の気泡含有率は
0.3％であり中央部20から外周面側部分30の気泡含有率
は1.0〜1.3％である。尚、通常外周面はガラス化の程度
が他の部分より低く、従って外周面近傍の気泡含有率は
最も大きい。FIG. 1 shows an example of a schematic partial sectional view of a quartz crucible according to the present invention and an internal bubble distribution graph thereof. In the illustrated example, almost no bubbles are observed in the inner peripheral side portion 10 of the quartz crucible, and the bubbles 11 are dispersed in the range from the central portion 20 inside the wall body to the outer peripheral surface side portion 30. The bubble content rate on the inner peripheral surface side 10 is
It is 0.3%, and the bubble content rate from the central portion 20 to the outer peripheral surface side portion 30 is 1.0 to 1.3%. The outer peripheral surface usually has a lower degree of vitrification than the other parts, and therefore the bubble content in the vicinity of the outer peripheral surface is the highest.
本発明の石英ルツボは、ルツボ製造時に原料の石英粉を
モールドに充填後、減圧下で加熱溶融する際に、減圧時
間、溶融時間および加熱温度などを調整することにより
製造できる。具体的には、石英粉を回転するモールドに
充填してモールド内周面に堆積させ、この石英粉層を減
圧状態に保ちつつ加熱溶融することにより、内周側の気
泡含有率が外周側の気泡含有率より格段に少ない石英ル
ツボが得られる。The quartz crucible of the present invention can be produced by filling the mold with the raw material quartz powder during the production of the crucible and then adjusting the depressurization time, the melting time, the heating temperature, etc. when heating and melting under reduced pressure. Specifically, by filling the rotating mold with quartz powder and depositing it on the inner peripheral surface of the mold, and heating and melting this quartz powder layer while maintaining the pressure reduction state, the bubble content rate on the inner peripheral side is reduced to the outer peripheral side. A quartz crucible having a much lower content than the bubble content can be obtained.
［発明の効果］ 本発明の石英ルツボは、従来の石英ルツボに比べて単結
晶化率が格段に良い。実用上、石英ルツボの単結晶化率
は70％以上であることが求められるが、本発明に係る石
英ルツボを用いた場合には75％に及ぶ高い単結晶化率を
達成することが出来る。[Effects of the Invention] The quartz crucible of the present invention has a remarkably better single crystallization rate than the conventional quartz crucible. Practically, the single crystallization rate of the quartz crucible is required to be 70% or more, but when the quartz crucible according to the present invention is used, a high single crystallization rate of up to 75% can be achieved.
［実施例及び比較例］ 同一の原料石英粉を用い、石英粉をモールドに充填後、
減圧下で加熱溶融する際に、減圧時間、溶融時間および
加熱温度などを調整することによりルツボの周壁および
底壁の内周部分と外周部分の気泡含有率を変えた石英ル
ツボを製造した。これらの石英ルツボを用いてシリコン
単結晶の引上げを行った。各石英ルツボの単結晶化率を
次表に示す。本発明に係る石英ルツボは何れも75％の単
結晶化率を示している。一方、従来の石英ルツボの単結
晶化率は45〜50％であり、本発明のルツボに比べ大幅に
低い。Example and Comparative Example Using the same raw material quartz powder, after filling the mold with the quartz powder,
When heating and melting under reduced pressure, a quartz crucible having different bubble content rates in the inner peripheral portion and the outer peripheral portion of the peripheral wall and bottom wall of the crucible was manufactured by adjusting the pressure reducing time, the melting time, the heating temperature, and the like. A silicon single crystal was pulled using these quartz crucibles. The single crystallization rate of each quartz crucible is shown in the following table. The quartz crucibles according to the present invention each show a single crystallization rate of 75%. On the other hand, the single crystallization rate of the conventional quartz crucible is 45 to 50%, which is significantly lower than that of the crucible of the present invention.
また本発明に係る試料（No1,2）について、その内周面
から外周面に至る断面の気泡分布グラフ第２図に示す。
更に比較例の試料（No3,4,5）について同様の内部気泡
の分布グラフを同図に示す。Further, regarding the samples (No. 1 and 2) according to the present invention, FIG. 2 is a bubble distribution graph of a cross section from the inner peripheral surface to the outer peripheral surface thereof.
Further, the same internal bubble distribution graph for the samples (No. 3, 4, 5) of the comparative example is shown in the same figure.
0.5％前後の気泡含有率は、従来のルツボにおいてマイ
クロバブルが残留する程度の気泡含有率である。従って
本発明に係る石英ルツボ全体の気泡含有率は、ルツボ全
体の気泡含有率を低下させた従来のルツボより寧ろ大き
いにも抱らず、はるかに高い単結晶化率を達成してい
る。The bubble content rate of about 0.5% is a bubble content rate at which micro bubbles remain in a conventional crucible. Therefore, the bubble content rate of the whole quartz crucible according to the present invention is much higher than that of the conventional crucible in which the bubble content rate of the entire crucible is lowered, but a much higher single crystallization rate is achieved.
第１図は、本発明に係る石英ルツボの模式的な部分断面
図と此れに対応する気泡分布グラフ、第２図は実施例と
比較例の内部気泡分布グラフである。 図面中、10……内周面側部分、20……中央部、30……外
周面側部分FIG. 1 is a schematic partial cross-sectional view of a quartz crucible according to the present invention and a bubble distribution graph corresponding thereto, and FIG. 2 is an internal bubble distribution graph of Examples and Comparative Examples. In the drawing, 10 …… Inner peripheral surface side portion, 20 …… Central portion, 30 …… Outer peripheral surface side portion
───────────────────────────────────────────────────── フロントページの続き (72)発明者 立野 信之 秋田県秋田市茨島５―14―３ 日本高純度 石英株式会社秋田工場内 (56)参考文献 特開 昭63−222091（ＪＰ，Ａ) 特開 平１−148783（ＪＰ，Ａ) ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nobuyuki Tateno 5-14-3 Ibaraki, Akita City, Akita Prefecture, Japan Akita Plant, Japan High-Purity Quartz Co., Ltd. (56) Reference JP-A-63-222091 (JP, A) Kaihei 1-14873 (JP, A)
Claims (1)
で溶融してルツボに成形する際に、減圧時間、溶融時間
および溶融温度を調整することにより製造された石英ル
ツボであって、ルツボ壁体の内周側部分の気泡含有率が
0.1〜0.5％であり、外周側部分の気泡含有率が内周側部
分の気泡含有率の２倍以上であることを特徴とするシリ
コン単結晶引上げ用石英ルツボ。1. A quartz crucible manufactured by adjusting a depressurizing time, a melting time and a melting temperature when the raw material quartz powder is filled in a mold and then melted under reduced pressure to form a crucible. The bubble content of the inner peripheral side of the crucible wall is
A quartz crucible for pulling a silicon single crystal, wherein the content of bubbles in the outer peripheral portion is 0.1 to 0.5%, and the content of bubbles in the outer peripheral portion is twice or more.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63021845A JPH0692276B2 (en) | 1988-02-03 | 1988-02-03 | Quartz crucible for pulling silicon single crystal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63021845A JPH0692276B2 (en) | 1988-02-03 | 1988-02-03 | Quartz crucible for pulling silicon single crystal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01197381A JPH01197381A (en) | 1989-08-09 |
| JPH0692276B2 true JPH0692276B2 (en) | 1994-11-16 |
Family
ID=12066430
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63021845A Expired - Lifetime JPH0692276B2 (en) | 1988-02-03 | 1988-02-03 | Quartz crucible for pulling silicon single crystal |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0692276B2 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3026088B2 (en) * | 1989-08-30 | 2000-03-27 | 三菱マテリアル株式会社 | Quartz crucible for pulling silicon single crystal |
| US6510707B2 (en) | 2001-03-15 | 2003-01-28 | Heraeus Shin-Etsu America, Inc. | Methods for making silica crucibles |
| JP4987029B2 (en) | 2009-04-02 | 2012-07-25 | ジャパンスーパークォーツ株式会社 | Silica glass crucible for pulling silicon single crystals |
| JP4907735B2 (en) * | 2009-04-28 | 2012-04-04 | 信越石英株式会社 | Silica container and method for producing the same |
| KR101315684B1 (en) | 2009-05-26 | 2013-10-10 | 신에쯔 세끼에이 가부시키가이샤 | Silica container and method for producing same |
| JP5306076B2 (en) * | 2009-06-29 | 2013-10-02 | 京セラ株式会社 | Junction structure, method for manufacturing junction structure, photoelectric conversion device, and method for manufacturing photoelectric conversion device |
| EP2476786B1 (en) | 2009-09-10 | 2014-02-19 | Japan Super Quartz Corporation | Silica glass crucible for pulling silicon single crystal and method for producing same |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3014311C2 (en) * | 1980-04-15 | 1982-06-16 | Heraeus Quarzschmelze Gmbh, 6450 Hanau | Process for the production of quartz glass crucibles and apparatus for carrying out this process |
| JPS5934659A (en) * | 1982-08-20 | 1984-02-25 | Toshiba Corp | Solid-state image pickup device |
| JPH0243720B2 (en) * | 1982-09-10 | 1990-10-01 | Toshiba Ceramics Co | HANDOTAISHORYOSEKIEIGARASUSEIROSHINKAN |
| JPS59213697A (en) * | 1983-05-20 | 1984-12-03 | Toshiba Ceramics Co Ltd | Pulling device for single crystal semiconductor |
| JPH0239455B2 (en) * | 1984-04-11 | 1990-09-05 | Toshiba Ceramics Co | SEKIEIGARASUJIGU |
| JPS6181648A (en) * | 1984-08-31 | 1986-04-25 | Toshiba Ceramics Co Ltd | Quartz glass jig for conveying wafer boat |
| US4632686A (en) * | 1986-02-24 | 1986-12-30 | Gte Products Corporation | Method of manufacturing quartz glass crucibles with low bubble content |
| JPH0788269B2 (en) * | 1987-03-10 | 1995-09-27 | 東芝セラミツクス株式会社 | Crucible for pulling silicon single crystal |
| JPH01148783A (en) * | 1987-12-03 | 1989-06-12 | Shin Etsu Handotai Co Ltd | Quartz crucible for pulling up single crystal |
-
1988
- 1988-02-03 JP JP63021845A patent/JPH0692276B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01197381A (en) | 1989-08-09 |
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