JPH0764673B2 - Quartz crucible manufacturing method - Google Patents
Quartz crucible manufacturing methodInfo
- Publication number
- JPH0764673B2 JPH0764673B2 JP2001457A JP145790A JPH0764673B2 JP H0764673 B2 JPH0764673 B2 JP H0764673B2 JP 2001457 A JP2001457 A JP 2001457A JP 145790 A JP145790 A JP 145790A JP H0764673 B2 JPH0764673 B2 JP H0764673B2
- Authority
- JP
- Japan
- Prior art keywords
- crucible
- quartz
- quartz powder
- quartz crucible
- melting
- 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
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B19/00—Other methods of shaping glass
- C03B19/09—Other methods of shaping glass by fusing powdered glass in a shaping mould
- C03B19/095—Other methods of shaping glass by fusing powdered glass in a shaping mould by centrifuging, e.g. arc discharge in rotating mould
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Liquid Deposition Of Substances Of Which Semiconductor Devices Are Composed (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、OH基濃度の少ない単結晶引上げ用石英ルツボ
の製造方法に関する。より詳しくは、回転モールド法に
よる製造方法において、比較的高い減圧下と溶融熱量下
で石英粉を加熱溶融することにより、ルツボ内表面から
所定深さのOH基濃度を低減する石英ルツボの製造方法に
関する。The present invention relates to a method for producing a quartz crucible for pulling a single crystal having a low OH group concentration. More specifically, in the manufacturing method by the rotational molding method, by heating and melting the quartz powder under a relatively high reduced pressure and heat of fusion, a method for manufacturing a quartz crucible that reduces the OH group concentration at a predetermined depth from the inner surface of the crucible. Regarding
シリコン単結晶引上げ用石英ルツボの内側表面近傍に含
有されるOH基がシリコン単結晶に与える影響について、
従来から種々検討されている。Regarding the effect of the OH groups contained in the vicinity of the inner surface of the quartz single crystal pulling crucible on the silicon single crystal,
Various studies have been conducted conventionally.
例えば特公昭58−49519号では、B2O31ppm以下、OH基300
ppm以下、その他の酸化物の合量が100ppm以下で、かつ1
450℃において109ポイズ以上の粘性を有する石英ルツボ
が提案され、また、特開昭61−44793号には、高濃度の
酸素も含有するシリコン単結晶を得る目的で内層のOH基
濃度を200ppm以上にした石英ルツボが提案されている。
更に、特開昭61−242984号には、内側表面に接して0.2m
m以上の領域のOH基を60ppm以上とした石英ルツボが提案
されている。この石英ルツボにおいては、石英ルツボの
内側表面に含まれるOH基の濃度を高くすることによりル
ツボ内側表面が溶融シリコン中に溶け込み易くし、これ
によって溶湯の動きを緩慢にしてルツボ内側表面の剥離
を防止することを意図している。For example, in Japanese Examined Patent Publication No. 58-49519, B 2 O 3 1 ppm or less, OH group 300
ppm or less, the total amount of other oxides is 100 ppm or less, and 1
A quartz crucible having a viscosity of 10 9 poise or more at 450 ° C. has been proposed, and in JP-A-61-44793, the OH group concentration of the inner layer is 200 ppm for the purpose of obtaining a silicon single crystal also containing a high concentration of oxygen. The quartz crucible described above has been proposed.
Further, in JP-A-61-242984, 0.2 m in contact with the inner surface
A quartz crucible having an OH group in the region of m or more of 60 ppm or more has been proposed. In this quartz crucible, by increasing the concentration of OH groups contained in the inner surface of the quartz crucible, the inner surface of the crucible easily melts into the molten silicon, thereby slowing the movement of the molten metal and removing the inner surface of the crucible. Intended to prevent.
本発明者等の研究によれば、OH基濃度の比較的高い石英
ルツボは、粘性が低いためルツボの溶損量が多くなり、
シリコン融液中の不純物と酸素濃度が結果的に高くなる
ために引き上げたシリコン単結晶の酸化誘引積層欠陥
（OSF）を生じる原因になり易い。更にOH基濃度の非常
に高い石英ルツボは高温において粘性が低いためシリコ
ン単結晶引上げ中にルツボが変形し易く、此れに起因し
て単結晶化歩留りが低下する問題がある。According to the research conducted by the present inventors, a quartz crucible having a relatively high OH group concentration has a large amount of melting loss due to its low viscosity.
As a result, the concentration of impurities and oxygen in the silicon melt becomes high, which tends to cause the oxidation-induced stacking fault (OSF) of the pulled silicon single crystal. Further, a quartz crucible having a very high OH group concentration has a low viscosity at a high temperature, so that the crucible is easily deformed during pulling of a silicon single crystal, which causes a problem that the yield of single crystallization is lowered.
一方、ルツボ内壁中のOH基を低減するにはOH基の少ない
石英粉を原料として用いることが必要であるが、天然に
存在する石英中のOH基濃度は比較的高く、しかも通常の
精製方法では必要な程度までOH基濃度を低減することが
できない。この他に、OH基はルツボ製造時に外部から取
り込まれる水分にも起因して増加する。On the other hand, in order to reduce the OH groups in the inner wall of the crucible, it is necessary to use quartz powder with a small amount of OH groups as a raw material, but the concentration of OH groups in naturally occurring quartz is relatively high, and the usual purification method However, the OH group concentration cannot be reduced to the required degree. In addition to this, OH groups also increase due to moisture taken in from the outside during crucible production.
本発明において、石英粉を溶融してルツボに製造する際
に、ルツボ内壁となる堆積された石英粉層を比較的高い
減圧下と溶融熱量下で加熱溶融することによりルツボ内
壁石英中のOH基を大幅に低減できることが見出された。
更に上記減圧操作により、ルツボ内壁のOH基濃度を50pp
m以下に減少した石英ルツボを使用すると酸素誘引積層
欠陥（OSF）の非常に少ないシリコン単結晶ウエハーが
得られることが判明した。In the present invention, when producing a crucible by melting the quartz powder, by heating and melting the deposited quartz powder layer to be the inner wall of the crucible under relatively high decompression and heat of fusion, OH groups in the inner wall quartz of the crucible It has been found that can be significantly reduced.
Further, by the above pressure reduction operation, the OH group concentration on the inner wall of the crucible was reduced to 50 pp.
It was found that the use of a quartz crucible reduced to m or less can yield a silicon single crystal wafer with very few oxygen-induced stacking faults (OSF).
本発明は上記知見に基づくものであり、本発明によれば
以下の構成からなる石英ルツボの製造方法が提供され
る。The present invention is based on the above findings, and the present invention provides a method for manufacturing a quartz crucible having the following configuration.
（１）回転モールドの内側にルツボの形状に石英粉を堆
積し、該石英粉を加熱溶融して石英ルツボを製造する方
法において、天然石英粉を用い、該石英粉を大気圧より
500mmHg以上低い減圧下で、かつ高溶融熱量で加熱溶融
することにより、ルツボ内表面から深さ1mmの範囲のOH
基濃度を50ppm以下に制御することを特徴とする石英ル
ツボの製造方法。(1) In a method for producing quartz crucible by depositing quartz powder in the shape of a crucible inside a rotary mold and heating and melting the quartz powder, natural quartz powder is used, and the quartz powder is heated from atmospheric pressure.
OH in the range of 1 mm depth from the inner surface of the crucible by heating and melting under a reduced pressure of 500 mmHg or more and with a high heat of fusion.
A method for producing a quartz crucible, which comprises controlling the base concentration to 50 ppm or less.
（２）石英粉を大気圧より500〜700mmHg低い減圧下で加
熱溶融することにより、上記OH基濃度を50〜35ppmに制
御する上記（１）に記載の石英ルツボの製造方法。(2) The method for producing a quartz crucible according to the above (1), wherein the OH group concentration is controlled to 50 to 35 ppm by heating and melting the quartz powder under a reduced pressure of 500 to 700 mmHg below atmospheric pressure.
本発明の製造方法によって得られるシリコン単結晶引上
げ用石英ルツボはその内側表面付近のOH基濃度が50ppm
以下であり、その範囲はルツボ内表面の全面において、
ルツボの内側表面から深さ1mmの領域である。該領域は
シリコン単結晶引上げ時に溶損する範囲であり、溶融シ
リコンへの影響を防止するにはこの領域のOH基を減少す
る必要がある。OH基の濃度が50ppmより多いと内面の侵
食が激しく、シリコン単結晶中にルツボからの不純物が
増加するので切り出したウエハーに酸化誘引積層欠陥
（OSF）を生じる原因となる。なお酸化誘引積層欠陥（O
SF）は、シリコンウエハーの表面を1000℃以上で酸化雰
囲気に晒した際に発生する積層欠陥である。The quartz crucible for pulling a silicon single crystal obtained by the manufacturing method of the present invention has an OH group concentration of 50 ppm near the inner surface thereof.
Below, the range is the entire inner surface of the crucible,
A region 1 mm deep from the inner surface of the crucible. This region is a range in which it is melted when the silicon single crystal is pulled, and it is necessary to reduce the OH group in this region in order to prevent the influence on the molten silicon. When the concentration of OH groups is higher than 50 ppm, the inner surface is severely eroded, and the impurities from the crucible increase in the silicon single crystal, which causes the oxidation-induced stacking fault (OSF) in the cut wafer. Oxidation induced stacking fault (O
SF) is a stacking fault that occurs when the surface of a silicon wafer is exposed to an oxidizing atmosphere at 1000 ° C or higher.
本発明の製造方法は回転モールド法に基づく。回転モー
ルド法においては、回転モールドの内表面に石英粉を堆
積して加熱溶融する際に同時に該堆積石英粉層を減圧し
て内部の気泡ないし水分を吸引除去する。具体的な減圧
方法の一例としては特願昭63−204778号に開示されてい
るように、内表面に開口する多数の吸引孔を有する回転
モールドを用い、該モールドの内表面に石英粉を堆積
し、その表面から高溶融熱量で加熱溶融すると同時にモ
ールド側から上記吸引孔を通じて石英粉堆積層内部を吸
引減圧する。ここで高溶融熱量とは従来の標準的な溶融
熱量よりも高いことを言う。具体的には、後述の第１表
に示すように、従来の標準的な溶融熱量を100とすると
き、これに対する相対的な溶融熱量が130以上である。
また、減圧度は500mmHg以上大気圧より低いことが必要
である。減圧度が大気圧より500mmHg未満であるとOH基
を気化して吸引除去するのが難しく、ルツボの内側表面
のOH基濃度を50ppm以下にすることができない。減圧時
間は加熱温度と加熱時間によって異なる。一例として、
150〜300kwで５〜10分間加熱し、その間に大気圧より50
0〜700mmHg低くなるように吸引して減圧する。The manufacturing method of the present invention is based on the rotational molding method. In the rotary mold method, when the quartz powder is deposited on the inner surface of the rotary mold and heated and melted, the deposited quartz powder layer is depressurized at the same time to remove air bubbles or moisture therein. As an example of a concrete depressurizing method, as disclosed in Japanese Patent Application No. 63-204778, a rotary mold having a large number of suction holes opened on the inner surface is used, and quartz powder is deposited on the inner surface of the mold. Then, the surface of the quartz powder deposition layer is heated and melted with a high amount of heat of fusion, and at the same time, the inside of the quartz powder deposition layer is sucked and depressurized from the mold side through the suction holes. Here, the high heat of fusion is higher than the conventional standard heat of fusion. Specifically, as shown in Table 1 below, when the conventional standard heat of fusion is 100, the heat of fusion relative to this is 130 or more.
The degree of pressure reduction is required to be 500 mmHg or more and lower than atmospheric pressure. If the degree of vacuum is less than 500 mmHg than atmospheric pressure, it is difficult to vaporize and remove the OH groups by suction, and the OH group concentration on the inner surface of the crucible cannot be reduced to 50 ppm or less. The decompression time depends on the heating temperature and the heating time. As an example,
Heat at 150-300kw for 5-10 minutes, during which 50
Suction and reduce the pressure to 0-700 mmHg.
本発明においては以上のように、従来の方法よりも加熱
温度がやや高く、かつ比較的高い減圧下で堆積石英粉層
を溶融するので、石英粉層中に含有される微量の水分が
確実に除去され、OH基の濃度が50ppm以下に減少する。As described above, in the present invention, the heating temperature is slightly higher than that of the conventional method, and the deposited quartz powder layer is melted under a relatively high reduced pressure, so that the trace amount of water contained in the quartz powder layer can be reliably ensured. It is removed, and the concentration of OH group is reduced to 50ppm or less.
本発明の石英ルツボはOH基が大幅に少ないので、シリコ
ン単結晶の引上げ中にルツボ内面の溶損も少なく、良質
のシリコン単結晶を得ることができる。またこの単結晶
から切り出したシリコンウエハーは酸化誘引積層欠陥が
低く、従って製品歩留りが高い。Since the quartz crucible of the present invention has much less OH groups, it is possible to obtain a good quality silicon single crystal with less melting loss on the inner surface of the crucible during the pulling of the silicon single crystal. Further, the silicon wafer cut out from this single crystal has a low oxidation-induced stacking fault, and therefore has a high product yield.
本発明の実施例を比較例と共に以下に示す。 Examples of the present invention are shown below together with comparative examples.
実施例１〜３ 同一の天然石英粉末を使用し、減圧度および溶融熱量を
それぞれ第１表に示す条件に設定し、回転モールディン
グ法により、16インチ径の石英ルツボを製造した。この
石英ルツボについて、ルツボの内側表面から深さ1mmの
範囲のOH基濃度を赤外線吸収法で測定した。この結果を
第１表に示す。Examples 1 to 3 The same natural quartz powder was used, the degree of vacuum and the heat of fusion were set to the conditions shown in Table 1, and a quartz crucible having a diameter of 16 inches was manufactured by the rotary molding method. With respect to this quartz crucible, the OH group concentration in the range of a depth of 1 mm from the inner surface of the crucible was measured by the infrared absorption method. The results are shown in Table 1.
比較例１〜４ 実施例に用いたのと同一の天然石英粉末を使用して、実
施例と同様に回転モールディング法により、16インチ径
の石英ルツボを製造した。各々の減圧度と溶融熱量は第
１表に示す通りである。製造した石英ルツボについて、
実施例と同様にOH基濃度を測定した。この結果を第１表
に示す。Comparative Examples 1 to 4 A quartz crucible having a diameter of 16 inches was manufactured by using the same natural quartz powder as that used in the example and by the rotary molding method as in the example. The degree of reduced pressure and the heat of fusion are shown in Table 1. About the manufactured quartz crucible,
The OH group concentration was measured in the same manner as in the examples. The results are shown in Table 1.
なお、比較例１の熱量は従来市販されている石英ルツボ
の製造の際に使用される熱量であり、それを比較基準10
0とした。因みに、比較例１に示す従来の石英ルツボの
標準的な熱量は50kwhである。The calorific value of Comparative Example 1 is the calorific value used in the production of a conventionally commercially available quartz crucible, which is used as a comparison standard 10
It was set to 0. Incidentally, the standard calorific value of the conventional quartz crucible shown in Comparative Example 1 is 50 kwh.
比較例１および２は溶融熱量が不十分であり、比較例３
および４は減圧度が低く、いずれもOH基濃度50ppm以上
である。これらの石英ルツボを用い、同一の条件で夫々
シリコン単結晶を製造し、該単結晶から夫々シリコンウ
エハーを採取した。得られたシリコンウエハーの中から
各単結晶について引き上げ開始部分、中間部分、および
引き上げ終了部分の夫々について、シリコンウエハーを
1100℃にて２時間保持した後に冷却し、ウエハー表面酸
化膜をフッ酸で溶解除去した後、選択性エッチングを行
ない、顕微鏡でライン状模様を数えてOSF密度を測定し
た。第２表にOSF密度の測定結果を示す。 Comparative Examples 1 and 2 have insufficient heat of fusion, and Comparative Example 3
And 4 have low degree of reduced pressure, and both have an OH group concentration of 50 ppm or more. Using these quartz crucibles, silicon single crystals were manufactured under the same conditions, and silicon wafers were sampled from the single crystals. From each of the obtained silicon wafers, a silicon wafer was taken for each of the pulling start portion, the intermediate portion, and the pulling end portion for each single crystal.
After holding at 1100 ° C. for 2 hours and cooling, the wafer surface oxide film was dissolved and removed with hydrofluoric acid, selective etching was performed, and line patterns were counted with a microscope to measure the OSF density. Table 2 shows the measurement results of the OSF density.
第２表の結果から明らかなように、本発明の石英ルツボ
によれば、酸化誘引積層欠陥（OSF）が非常に少ないシ
リコン単結晶ウエハーを得ることができる。 As is clear from the results shown in Table 2, according to the quartz crucible of the present invention, it is possible to obtain a silicon single crystal wafer having very few oxidation induced stacking faults (OSF).
Claims (2)
粉を堆積し、該石英粉を加熱溶融して石英ルツボを製造
する方法において、天然石英粉を用い、該石英粉を大気
圧より500mmHg以上低い減圧下で、かつ高溶融熱量で加
熱溶融することにより、ルツボ内表面から深さ1mmの範
囲のOH基濃度を50ppm以下に制御することを特徴とする
石英ルツボの製造方法。1. A method for producing a quartz crucible by depositing quartz powder in the shape of a crucible inside a rotary mold and heating and melting the quartz powder, wherein natural quartz powder is used, and the quartz powder is 500 mmHg from atmospheric pressure. A method for producing a quartz crucible, characterized in that the OH group concentration in a range of a depth of 1 mm from the inner surface of the crucible is controlled to 50 ppm or less by heating and melting under a low reduced pressure and a high heat of fusion.
下で加熱溶融することにより、上記OH基濃度を50〜35pp
mに制御する請求項１に記載の石英ルツボの製造方法。2. The above OH group concentration is 50 to 35 pp by melting and melting quartz powder under reduced pressure 500 to 700 mmHg lower than atmospheric pressure.
The method for producing a quartz crucible according to claim 1, wherein the method is controlled to m.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001457A JPH0764673B2 (en) | 1990-01-10 | 1990-01-10 | Quartz crucible manufacturing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001457A JPH0764673B2 (en) | 1990-01-10 | 1990-01-10 | Quartz crucible manufacturing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03208880A JPH03208880A (en) | 1991-09-12 |
| JPH0764673B2 true JPH0764673B2 (en) | 1995-07-12 |
Family
ID=11501984
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2001457A Expired - Lifetime JPH0764673B2 (en) | 1990-01-10 | 1990-01-10 | Quartz crucible manufacturing method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0764673B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4995069B2 (en) * | 2007-12-28 | 2012-08-08 | ジャパンスーパークォーツ株式会社 | Internal crystallization crucible and pulling method using the crucible |
| JP4995068B2 (en) | 2007-12-28 | 2012-08-08 | ジャパンスーパークォーツ株式会社 | Silica glass crucible for pulling silicon single crystals |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2263589C2 (en) * | 1972-12-27 | 1974-05-30 | Heraeus Schott Quarzschmelze Gmbh, 6450 Hanau | Method for producing hollow cylinders, in particular tubes, from quartz glass and device for carrying out the method |
| 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 |
| JPS5849519A (en) * | 1981-09-07 | 1983-03-23 | Toyota Motor Corp | Body floor structure of automobile |
| 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 |
| JPS59137397A (en) * | 1983-01-26 | 1984-08-07 | Toshiba Ceramics Co Ltd | Bell jar made of quartz glass |
| JPS59213697A (en) * | 1983-05-20 | 1984-12-03 | Toshiba Ceramics Co Ltd | Pulling device for single crystal semiconductor |
| JPS61242984A (en) * | 1985-04-19 | 1986-10-29 | Shinetsu Sekiei Kk | Crucible for pulling up silicon single crystal |
| US4632686A (en) * | 1986-02-24 | 1986-12-30 | Gte Products Corporation | Method of manufacturing quartz glass crucibles with low bubble content |
| JP2561105B2 (en) * | 1987-12-15 | 1996-12-04 | 東芝セラミックス株式会社 | Quartz glass crucible manufacturing method |
| JPH0643277B2 (en) * | 1988-03-18 | 1994-06-08 | コマツ電子金属株式会社 | Quartz crucible manufacturing method |
| JPH029783A (en) * | 1988-06-28 | 1990-01-12 | Shin Etsu Chem Co Ltd | Quartz crucible |
-
1990
- 1990-01-10 JP JP2001457A patent/JPH0764673B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH03208880A (en) | 1991-09-12 |
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