JP3304131B2 - How to dehydrate quartz powder - Google Patents
How to dehydrate quartz powderInfo
- Publication number
- JP3304131B2 JP3304131B2 JP21559092A JP21559092A JP3304131B2 JP 3304131 B2 JP3304131 B2 JP 3304131B2 JP 21559092 A JP21559092 A JP 21559092A JP 21559092 A JP21559092 A JP 21559092A JP 3304131 B2 JP3304131 B2 JP 3304131B2
- Authority
- JP
- Japan
- Prior art keywords
- quartz powder
- quartz
- gas
- chlorine
- dehydrate
- 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
Classifications
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B15/00—Single-crystal growth by pulling from a melt, e.g. Czochralski method
- C30B15/10—Crucibles or containers for supporting the melt
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C1/00—Ingredients generally applicable to manufacture of glasses, glazes, or vitreous enamels
- C03C1/02—Pretreated ingredients
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
- C30B29/02—Elements
- C30B29/06—Silicon
Description
【０００１】[0001]
【産業上の利用分野】本発明は、半導体用シリコン単結
晶を引き上げるのに用いる石英ルツボの製造の際に、製
造原料である石英粉についての好適な脱水方法に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suitable method for dehydrating quartz powder as a raw material for producing a quartz crucible used for pulling a silicon single crystal for a semiconductor.
【０００２】[0002]
【従来技術とその問題点】半導体用シリコン単結晶は、
主に、フローティングゾーン法（ＦＺ法）や引上げ法
（ＣＺ法）によって製造されている。引上げ法は、溶融
した多結晶シリコンから単結晶シリコンを凝固させなが
ら引上げる方法であり、多結晶シリコンを溶融して溜め
るために石英ルツボが用いられる。多結晶シリコンを入
れた石英ルツボはシリコンの融点（約1414℃）以上に加
熱される。石英の軟化点は約1550℃であるが、高温に加
熱された溶融シリコンによって石英ルツボの内壁面は次
第に溶損し、一回の引上げでルツボの内壁面の厚さが約
0.7 〜1.0mm 程度減少する。従って、石英ルツボに不純
物が混入していると、これがシリコン融液に取り込ま
れ、単結晶化率を大幅に低下させ、またシリコン単結晶
の不純物汚染の原因となる。このため、石英ルツボの製
造原料としては高純度の石英粉が用いられている。因み
に、ルツボ用石英粉として、現在主に天然石英粉が用い
られているが、特に高純度が要求される場合は、天然石
英以上の純度の得られる合成石英粉が用いられており、
不純物の混入を極力防止している。2. Description of the Related Art Silicon single crystals for semiconductors are:
It is mainly manufactured by a floating zone method (FZ method) or a pulling method (CZ method). The pulling method is a method of pulling single crystal silicon while solidifying it from molten polycrystalline silicon, and a quartz crucible is used to melt and store the polycrystalline silicon. A quartz crucible containing polycrystalline silicon is heated above the melting point of silicon (about 1414 ° C.). Although the softening point of quartz is about 1550 ° C, the inner wall surface of the quartz crucible gradually melts down due to the molten silicon heated to a high temperature, and the thickness of the inner wall surface of the crucible increases by about one pull.
It is reduced by about 0.7 to 1.0 mm. Therefore, if impurities are mixed in the quartz crucible, they are taken into the silicon melt, greatly lowering the single crystallization rate and causing impurity contamination of the silicon single crystal. For this reason, high-purity quartz powder is used as a raw material for producing a quartz crucible. By the way, as quartz powder for crucibles, natural quartz powder is mainly used at present, but in particular, when high purity is required, synthetic quartz powder having a purity higher than natural quartz is used.
The contamination of impurities is prevented as much as possible.
【０００３】石英粉に含まれる水分も同様であり、ＯＨ
基含有量の高いルツボを使用するとルツボの加熱時にル
ツボの壁体内部に微細な気泡が発生し、これが単結晶化
率を低下させる原因となる。またＯＨ基が高いと高温強
度が低下し、シリコン単結晶引上げ時にルツボが変型し
て引上げ不能となることがある。このため、ＯＨ基の高
い石英粉を原料として石英ルツボを製造する際には、石
英粉の脱水処理が不可欠である。従来行われている脱水
方法は、石英粉を約1400℃程度に加熱して乾燥する方法
であるが、粒径約１５０μm の石英粒子に含まれている
ＯＨ基を加熱によって５０ppm 程度に低下するには約４
８時間前後に及ぶ長時間の加熱処理が必要であり、ＯＨ
基含有量をさらに５０ppm 以下に除去するのは難しい。
また脱水効果を高めるために加熱温度を上げると加熱炉
炉材の損傷が急増し石英粉の焼結を招く虞がある。[0003] The same applies to water contained in quartz powder, and OH
When a crucible having a high group content is used, fine bubbles are generated inside the crucible wall when the crucible is heated, and this causes a reduction in the rate of single crystallization. If the OH group is high, the high-temperature strength is reduced, and the crucible may be deformed at the time of pulling a silicon single crystal, making it impossible to pull. Therefore, when a quartz crucible is manufactured using quartz powder having a high OH group as a raw material, dehydration treatment of the quartz powder is indispensable. The conventional dehydration method is a method in which quartz powder is heated to about 1400 ° C. and dried.However, it is necessary to reduce the OH group contained in quartz particles having a particle size of about 150 μm to about 50 ppm by heating. Is about 4
A long heat treatment of about 8 hours is required, and OH
It is difficult to further reduce the group content to 50 ppm or less.
If the heating temperature is increased to enhance the dewatering effect, damage to the furnace material of the heating furnace may increase rapidly and sintering of the quartz powder may occur.
【０００４】[0004]
【発明の解決課題】本発明は、従来の加熱による脱水方
法における上記問題を解決した脱水方法を提供すること
を目的とし、比較的低温で、かつ短時間で高い脱水効果
を達成し、後処理も不要な脱水方法を提供するものであ
る。SUMMARY OF THE INVENTION An object of the present invention is to provide a dehydration method which solves the above-mentioned problems in the conventional dehydration method by heating. Also provide an unnecessary dehydration method.
【０００５】[0005]
【課題の解決手段：発明の構成】本発明によれば、半導
体用シリコン単結晶を引き上げるのに用いる石英ルツボ
の製造原料として用いる石英粉の脱水方法であって、石
英粉に、１０００〜１５００℃の温度下で、塩素ガスま
たは塩素含有化合物ガスを０.１〜１０％含有する流動
化ガスを導入し、該石英粉を流動化状態で上記流動化ガ
スに接触させて脱水することによってＯＨ基含有量を５
０ppm以下に低減することを特徴とする石英粉の脱水方
法が提供される。According to the present invention, there is provided a method for dehydrating quartz powder used as a raw material for producing a quartz crucible used for pulling a silicon single crystal for a semiconductor. A fluidizing gas containing 0.1 to 10% of chlorine gas or a chlorine-containing compound gas at a temperature of, and bringing the quartz powder into contact with the fluidizing gas in a fluidized state to dehydrate the quartz powder to form an OH group. 5 content
A method for dewatering quartz powder, characterized in that the method is reduced to 0 ppm or less.
【０００６】石英粉としては、天然石英粉と合成石英粉
の何れも用いることができる。通常、天然石英粉のＯＨ
基含有量は４０〜６０ppm であり、合成石英粉のＯＨ基
含有量は６０〜１０００ppm である。石英粉の粒度は制
限されないが、通常、石英ルツボの製造原料としては粒
径約１５０μm 前後の石英粉が用いられている。As quartz powder, either natural quartz powder or synthetic quartz powder can be used. Usually, OH of natural quartz powder
The group content is 40 to 60 ppm, and the OH group content of the synthetic quartz powder is 60 to 1000 ppm. Although the particle size of the quartz powder is not limited, quartz powder having a particle size of about 150 μm is usually used as a raw material for producing a quartz crucible.
【０００７】好ましくは、流動床を用い、石英粉を１０
００〜１６００℃の温度下で、塩素ガスまたは塩素含有
化合物ガスを含有する空気などの流動化ガスを導入して
該石英粉を流動化した状態で脱水する。塩素含有化合物
としては、導入温度において石英と反応せずに塩素を放
出するものであればよく、具体的には、ＣＯＣｌ2 、Ｓ
ＯＣｌ2 、ＳＯ2 Ｃｌ2 などを用いることができる。塩
素ガスおよび放出された塩素は、上記温度下において石
英粉のＯＨ基と結合して塩化水素を生成する。この塩化
水素は空気などの流動化ガスおよび未反応の塩素ガス等
と共に外部に排出される。Preferably, a fluidized bed is used, and quartz powder is
At a temperature of 00 to 1600 ° C., a fluidizing gas such as air containing chlorine gas or chlorine-containing compound gas is introduced to dehydrate the quartz powder in a fluidized state. The chlorine-containing compound may be any compound that releases chlorine without reacting with quartz at the introduction temperature. Specifically, COCl 2 , S
OCl 2 , SO 2 Cl 2, or the like can be used. The chlorine gas and the released chlorine combine with the OH groups of the quartz powder at the above temperature to generate hydrogen chloride. The hydrogen chloride is discharged to the outside together with a fluidizing gas such as air and unreacted chlorine gas.
【０００８】導入する塩素ガスまたは塩素含有化合物ガ
スの量は、塩素ガス換算で、石英粉１kg当たり０．０５
リットル/min程度であれば良い。具体的には、空気を導
入して石英粉を流動化する場合、塩素ガスまたは塩素含
有化合物ガスの量は、導入ガス中、塩素ガスに換算して
０．１〜１０％程度含有されていればよい。また、流動
化ガスの導入量は石英粉を流動化するに足りる量であれ
ばよい。塩素ガスの導入量が少ないと、石英粉の脱水に
時間がかかり、また導入量が多過ぎると、脱水効果は変
わらずに排ガス処理の負担が増すので好ましくない。The amount of chlorine gas or chlorine-containing compound gas to be introduced is 0.05% per 1 kg of quartz powder in terms of chlorine gas.
It may be about liter / min. Specifically, when the quartz powder is fluidized by introducing air, the amount of chlorine gas or chlorine-containing compound gas in the introduced gas may be about 0.1 to 10% in terms of chlorine gas. I just need. The amount of the fluidizing gas introduced may be an amount sufficient to fluidize the quartz powder. If the introduction amount of chlorine gas is small, it takes a long time to dehydrate the quartz powder, and if the introduction amount is too large, the load of exhaust gas treatment increases without changing the dehydration effect, which is not preferable.
【０００９】[0009]
実施例 平均粒径１５０μm 、ＯＨ基含有量７０ppm の非晶質合
成石英粉２００ｇを容量０．５lit.の流動槽に装入し、
１２００℃の温度下で、塩素ガスを１％含有する空気を
４lit/min の割合で槽内に導入し、石英粉を流動化した
状態で２時間脱水処理したところ、石英粉のＯＨ基含有
量は４５ppm に低下した。 比較例 一方、実施例と同様の石英粉200gを電気炉に装入し、14
00℃に加熱して４８時間脱水処理を行ったところ、石英
粉のＯＨ基含有量は５０ppm であった。Example 200 g of amorphous synthetic quartz powder having an average particle diameter of 150 μm and an OH group content of 70 ppm was charged into a fluidizing tank having a capacity of 0.5 lit.
At a temperature of 1200 ° C., air containing 1% of chlorine gas was introduced into the tank at a rate of 4 lit / min, and the quartz powder was dehydrated for 2 hours in a fluidized state. Dropped to 45 ppm. Comparative Example On the other hand, 200 g of the same quartz powder as in the example was charged into an electric furnace, and 14
When heated to 00 ° C. and dehydrated for 48 hours, the OH group content of the quartz powder was 50 ppm.
【００１０】実施例および比較例の結果を次表に示す。The results of the examples and comparative examples are shown in the following table.
【表１】 [Table 1]
【００１１】[0011]
【発明の効果】本発明の脱水方法によれば、従来よりも
低い温度で石英粉の脱水処理を行なうことができ、従来
みられた石英粉の焼結を生じる虞がなく後処理が不要で
ある。さらに、従来の方法では、必要な脱水効果を達成
するには４８時間に及ぶ長時間の加熱処理が必要であっ
たが、本発明の方法では約２時間の処理で済み、処理時
間が大幅に短縮される。しかも、従来の方法ではＯＨ基
含有量を５０ppm 以下に低下させるのは困難であった
が、本発明の脱水方法によれば、短時間で４８ppm程度
にまで脱水することができる。この結果、本発明の方法
によって脱水した石英粉を原料として製造した石英ルツ
ボはＯＨ基含有量が少ないために高温強度が大きく、し
かも気泡含有率が極めて小さいので、シリコン単結晶の
引上げに用いると、単結晶化率が高く不純物の少ない良
質の単結晶シリコンを得ることができる。According to the dehydration method of the present invention, the quartz powder can be dehydrated at a lower temperature than in the prior art, and there is no risk of sintering of the quartz powder, which is conventionally seen, and post-treatment is unnecessary. is there. Furthermore, in the conventional method, a long heat treatment of up to 48 hours was required to achieve the required dehydration effect. However, in the method of the present invention, a treatment of about 2 hours was sufficient, and the treatment time was greatly reduced. Be shortened. Moreover, it was difficult to reduce the OH group content to 50 ppm or less by the conventional method, but according to the dehydration method of the present invention, it is possible to dehydrate to about 48 ppm in a short time. As a result, quartz crucibles produced using quartz powder dehydrated by the method of the present invention as raw materials have a high high-temperature strength due to a low OH group content and a very low bubble content, so that they can be used for pulling silicon single crystals. In addition, high-quality single-crystal silicon having a high single-crystallization rate and a small amount of impurities can be obtained.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平４−154613（ＪＰ，Ａ) 特開 昭55−167143（ＪＰ，Ａ) 特開 昭56−100145（ＪＰ，Ａ) 特開 平２−289416（ＪＰ，Ａ) 特開 平４−83711（ＪＰ，Ａ) 特公 昭42−23036（ＪＰ，Ｂ１) (58)調査した分野(Int.Cl.7，ＤＢ名) C01B 33/113 - 33/193 ──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-4-154613 (JP, A) JP-A-55-167143 (JP, A) JP-A-56-100145 (JP, A) JP-A-2- 289416 (JP, A) JP-A-4-83711 (JP, A) JP-B-42-23036 (JP, B1) (58) Fields investigated (Int. Cl. 7 , DB name) C01B 33/113-33 / 193
Claims (1)
に用いる石英ルツボの製造原料として用いる石英粉の脱
水方法であって、石英粉に、１０００〜１５００℃の温
度下で、塩素ガスまたは塩素含有化合物ガスを０．１〜
１０％含有する流動化ガスを導入し、該石英粉を流動化
状態で上記流動化ガスに接触させて脱水することによっ
てＯＨ基含有量を５０ppm以下に低減することを特徴と
する石英粉の脱水方法。1. A method for pulling a silicon single crystal for a semiconductor.
Of quartz powder used as a raw material for the production of quartz crucibles
A water method, wherein a quartz powder is heated to a temperature of 1000 to 1500 ° C.
Temperature, the chlorine gas or chlorine-containing compound gas
Fluidizing gas containing 10% is introduced to fluidize the quartz powder.
In contact with the fluidizing gas to dehydrate
A method for dehydrating quartz powder , comprising reducing the OH group content to 50 ppm or less .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21559092A JP3304131B2 (en) | 1992-07-21 | 1992-07-21 | How to dehydrate quartz powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21559092A JP3304131B2 (en) | 1992-07-21 | 1992-07-21 | How to dehydrate quartz powder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0640713A JPH0640713A (en) | 1994-02-15 |
| JP3304131B2 true JP3304131B2 (en) | 2002-07-22 |
Family
ID=16674953
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21559092A Expired - Fee Related JP3304131B2 (en) | 1992-07-21 | 1992-07-21 | How to dehydrate quartz powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3304131B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7975507B2 (en) * | 2005-02-04 | 2011-07-12 | Asahi Glass Company, Limited | Process for producing synthetic quartz glass and synthetic quartz glass for optical member |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4453954B2 (en) * | 2003-02-28 | 2010-04-21 | 信越石英株式会社 | Method for producing quartz glass crucible for pulling silicon single crystal and quartz glass crucible produced by the production method |
| US7341702B2 (en) | 2004-12-28 | 2008-03-11 | Momentive Performance Materials Inc. | Process for producing boron nitride |
| US7452518B2 (en) | 2004-12-28 | 2008-11-18 | Momentive Performance Materials Inc. | Process for treating synthetic silica powder and synthetic silica powder treated thereof |
| TWI370801B (en) | 2005-10-28 | 2012-08-21 | Japan Super Quartz Corp | Purification method of silica powder, purification apparatus thereof, and purified silica powder |
| CN105036545B (en) * | 2015-06-30 | 2018-03-02 | 湘潭大学 | The process of gas liquid inclusion in a kind of rejecting glass sand |
| CN107297273A (en) * | 2017-07-25 | 2017-10-27 | 安徽正丰再生资源有限公司 | A kind of silica production purifying plant |
| CN117120366A (en) * | 2021-03-31 | 2023-11-24 | 电化株式会社 | Metal oxide powder and method for producing same |
| KR20230150344A (en) * | 2021-03-31 | 2023-10-30 | 덴카 주식회사 | Silica powder and method for producing the same |
-
1992
- 1992-07-21 JP JP21559092A patent/JP3304131B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7975507B2 (en) * | 2005-02-04 | 2011-07-12 | Asahi Glass Company, Limited | Process for producing synthetic quartz glass and synthetic quartz glass for optical member |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0640713A (en) | 1994-02-15 |
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