JP2010269992A - Method and apparatus for refining metallic silicon - Google Patents
Method and apparatus for refining metallic silicon Download PDFInfo
- Publication number
- JP2010269992A JP2010269992A JP2009176506A JP2009176506A JP2010269992A JP 2010269992 A JP2010269992 A JP 2010269992A JP 2009176506 A JP2009176506 A JP 2009176506A JP 2009176506 A JP2009176506 A JP 2009176506A JP 2010269992 A JP2010269992 A JP 2010269992A
- Authority
- JP
- Japan
- Prior art keywords
- metal silicon
- crucible
- purifying
- heating means
- local heating
- 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.)
- Pending
Links
Images
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
- C30B31/00—Diffusion or doping processes for single crystals or homogeneous polycrystalline material with defined structure; Apparatus therefor
- C30B31/06—Diffusion or doping processes for single crystals or homogeneous polycrystalline material with defined structure; Apparatus therefor by contacting with diffusion material in the gaseous state
- C30B31/16—Feed and outlet means for the gases; Modifying the flow of the gases
-
- 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
-
- 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
- C30B35/00—Apparatus not otherwise provided for, specially adapted for the growth, production or after-treatment of single crystals or of a homogeneous polycrystalline material with defined structure
- C30B35/002—Crucibles or containers
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/546—Polycrystalline silicon PV cells
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Crystallography & Structural Chemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Silicon Compounds (AREA)
- Photovoltaic Devices (AREA)
Abstract
Description
本発明は太陽電池の生産に適合する金属シリコンの精製方法とその精製装置に関し、詳細には、以前から広く使用されているシリコン単結晶製造装置を用いて 2Nの低純度金属シリコン(例えば、鉄鋼産業やアルミニウム産業に広く用いられている金属シリコン)を太陽電池の生産に適合する6〜7Nの高純度金属シリコンに精製することができる金属シリコンの精製方法とその精製装置に関する。 The present invention relates to a method and apparatus for purifying metallic silicon suitable for the production of solar cells, and more specifically, 2N low-purity metallic silicon (for example, steel) using a silicon single crystal production apparatus that has been widely used for a long time. The present invention relates to a metal silicon purification method and a purification apparatus capable of refining metal silicon, which is widely used in industry and aluminum industry, into 6 to 7N high-purity metal silicon suitable for solar cell production.
従来、太陽電池の生産に使用された多結晶(金属)シリコンは、いわゆるシーメンス法と呼ばれる方法によって生産されている。
上記シーメンス(Siemens)法は長年実施されており、技術と実績が豊かで、製品の品質に優れており、太陽電池の生産に全く問題がない。
一般的に太陽電池は純度6〜7N(99.9999〜99.99999%)の高純度金属シリコンが使用される。
しかし、昨今の急激な市場拡大に伴う供給市場が要求する価格に対しては全く対応することができない欠点を有する。
すなわち、上記シーメンス(Siemens)法によって生産された金属シリコンの品質は、太陽電池用として使用されるのに不要に高品質であり、高品質で生産されることで価格が高い短所がある。また、生産原理上、生産時に塩酸(HCl)、三塩化シラン(SiHCl3)、水素(H2)が必要であり、また、生産中に発生する四塩化シラン(SiCl4)を含み、すべての生産材料は有害で爆発する危険性があり、現在社会が要求するクリーンな環境的側面から見ても、問題のある生産方式であると言える。
また、冶金法によって太陽電池の生産に使用可能な純度を有する金属シリコンを生産する方法も下記のように報告されている。
Conventionally, polycrystalline (metal) silicon used for the production of solar cells is produced by a so-called Siemens method.
The Siemens method described above has been implemented for many years, has rich technology and achievements, excellent product quality, and no problem in solar cell production.
Generally, high-purity metallic silicon having a purity of 6 to 7N (99.9999 to 99.99999%) is used for the solar cell.
However, it has the disadvantage that it cannot cope with the price required by the supply market accompanying the recent rapid market expansion.
That is, the quality of the metal silicon produced by the Siemens method is unnecessarily high quality when used for solar cells, and has a disadvantage of high price due to high quality production. In addition, due to the production principle, hydrochloric acid (HCl), silane trichloride (SiHCl 3 ), and hydrogen (H 2 ) are required at the time of production. Also, tetrachlorosilane (SiCl 4 ) generated during production is included. Production materials are harmful and dangerous to explode, and it can be said that this is a problematic production system even from the viewpoint of clean environmental aspects currently demanded by society.
In addition, a method for producing metallic silicon having a purity that can be used for production of solar cells by metallurgical methods has been reported as follows.
本発明は上記のような問題点を解決するためのものであり、本発明は以前から広く使用されているシリコン単結晶製造装置を用いて2N(99%)の低純度シリコン(例えば、鉄鋼産業やアルミニウム産業に広く使用された金属シリコン)を太陽電池の原料として使用可能な6〜7N(99.9999〜99.99999%)水準のシリコンを精製することができる金属シリコンの精製方法及びその精製装置を提供することに目的がある。
すなわち、本発明は従来の技術が有する問題点をすべて解決すると同時に、簡単な設備面でも従来からシリコン単結晶生産用として使用されていた設備を改造することによって、太陽電池の生産に必要な品質の多結晶金属シリコンを生産することができる金属シリコンの精製方法及びその精製装置を提供することに目的がある。
The present invention is for solving the above-mentioned problems, and the present invention uses 2N (99%) low-purity silicon (for example, the steel industry) using a silicon single crystal manufacturing apparatus that has been widely used. And metal silicon widely used in the aluminum industry) and a method for purifying metal silicon capable of purifying 6 to 7N (99.9999 to 99.99999%) level silicon that can be used as a raw material for solar cells, and purification thereof There is an objective to provide a device.
That is, the present invention solves all the problems of the conventional technology, and at the same time, by remodeling the equipment that has been used for silicon single crystal production from the viewpoint of simple equipment, the quality required for the production of solar cells is achieved. It is an object of the present invention to provide a metal silicon refining method and a refining apparatus capable of producing polycrystalline metal silicon.
上記目的を果たそうと本発明である金属シリコンの精製装置は、真空が可能なチャンバと、上記チャンバ内側に設けられて溶融金属シリコンを保存する坩堝と、上記坩堝を支持し、回転と上下移動が可能な坩堝支持体と、上記坩堝に保存された金属シリコンを加熱して溶融させる加熱手段と、上記坩堝に保存された溶融金属シリコンの上部表面を局部的に加熱するプラズマ(Plasma)銃で形成された局部加熱手段と、上記坩堝に保存された溶融金属シリコンの上部表面に不純物除去用物質を供給するガス供給管と、上記坩堝上部と離隔して設けられてガス供給管から供給される不純物除去用物質と坩堝内で発生したガスの流動を案内するガス誘導手段を含むように構成される。
上記坩堝下部には局部加熱手段によって局部加熱されることで破損されることを防止しようと熱伝逹を遮断する第1遮断手段がさらに形成され、上記坩堝支持体には局部加熱手段によって局部加熱されることで破損されることを防止しようと熱伝達を遮断する第2遮断手段がさらに形成される。
上記目的を達成しようと本発明である金属シリコンの精製方法は、低純度金属シリコンを出発原料として、太陽電池の生産に必要な純度に精製するに際して、坩堝内の金属シリコン表面を局部的に加熱する局部加熱手段を備えて表面に表面温度差を形成する金属シリコンの精製方法である。
上記表面温度差は摂氏50度以上の温度差を形成するのが好ましく、上記局部加熱手段はプラズマ(Plasma)が使用される。
上記坩堝内に供給されてモノシランと酸素と水素を発生させる不純物除去用物質が供給され、上記不純物除去用物質はO2、O3、H2、H2O、H2O2、HCLO4のうち何れか一つを選択して使用し、上記不純物除去用物質は1〜500cc/minの速度で溶融された金属シリコン表面に供給される。
上記プラズマ(Plasma)を断続的に照射し、上記不純物除去用物質を断続的に供給するのが好ましい。
上記金属シリコンに塩素(Cl)または金属シリコンに含有された不純物と反応して塩素(Cl)を形成する物質を添加することができ、上記物質はCl2、CCl4、HCl、ClF3のうち何れか一つを選択して使用する。
In order to achieve the above object, the metal silicon refining apparatus according to the present invention comprises a chamber capable of vacuum, a crucible provided inside the chamber for storing molten metal silicon, and supporting the crucible, and rotating and moving up and down. Formed by a possible crucible support, heating means for heating and melting the metal silicon stored in the crucible, and a plasma (Plasma) gun for locally heating the upper surface of the molten metal silicon stored in the crucible Local heating means, a gas supply pipe for supplying a substance for removing impurities to the upper surface of the molten metal silicon stored in the crucible, and an impurity provided separately from the upper part of the crucible and supplied from the gas supply pipe Gas removal means for guiding the flow of the gas generated in the crucible and the removing material is included.
The crucible lower part is further formed with a first shut-off means for shutting off the heat transfer in order to prevent damage by being locally heated by the local heating means, and the crucible support is locally heated by the local heating means. A second blocking means for blocking heat transfer is further formed so as to prevent damage from being caused.
In order to achieve the above object, the method for purifying metal silicon according to the present invention uses a low-purity metal silicon as a starting material and locally heats the surface of the metal silicon in the crucible when purifying to the purity required for solar cell production. This is a method for purifying metallic silicon that includes a local heating means that forms a surface temperature difference on the surface.
The surface temperature difference preferably forms a temperature difference of 50 degrees Celsius or more, and plasma is used as the local heating means.
A substance for removing impurities that is supplied into the crucible and generates monosilane, oxygen, and hydrogen is supplied. The substances for removing impurities are O 2 , O 3 , H 2 , H 2 O, H 2 O 2 , HCLO 4 . Any one of them is selected and used, and the impurity removing substance is supplied to the molten metal silicon surface at a rate of 1 to 500 cc / min.
It is preferable to intermittently irradiate the plasma and supply the impurity removing substance intermittently.
The metal silicon can be added with chlorine (Cl) or a substance that reacts with impurities contained in the metal silicon to form chlorine (Cl), and the substance is selected from Cl 2 , CCl 4 , HCl, and ClF 3 . Select any one to use.
上記のように構成される本発明の金属シリコンの精製装置は、従来使用されているシリコン単結晶製造装置を改造して使用することができ、設備費用を節約することができる特徴がある。
本発明は従来のシーメンス法が有するすべての問題を解決した画期的な発明であり、有害物質の使用による安全性の問題点と環境汚染に対する問題点を解決することができ、簡単にターンキー(Turnkey)で生産が実行され、必要なすべての精製工程を1工程、1設備で同時に所要工程が実行可能な特徴を有し、一方では生産調整を柔軟に調節することができる特徴がある。
すなわち、本発明である金属シリコンの精製方法及びその精製装置は従来使用されているシリコン単結晶製造装置を改造して使用することができ、一台の装置で精製に必要なすべての工程がターンキーで実行され、精製工程で有毒、危険物質を全く使用せず、柔軟に生産が行われる特徴がある。
したがって、生産原価を従来より1/4以下の低価で生産することができ、製造装置の設備費と設置期間を1/5以下に短縮することができる特徴がある。
The metal silicon refining apparatus of the present invention configured as described above is characterized in that it can be used by modifying a conventionally used silicon single crystal manufacturing apparatus, and can save equipment costs.
The present invention is an epoch-making invention that solves all the problems of the conventional Siemens method, can solve the problems of safety due to the use of harmful substances and the problems of environmental pollution, and can be easily turnkey. (Turnkey) has a feature that production can be performed and all necessary refining processes can be performed in one process and one facility at the same time, while the necessary processes can be performed at the same time, while production adjustment can be flexibly adjusted.
That is, the metal silicon refining method and the refining apparatus according to the present invention can be used by modifying a conventionally used silicon single crystal manufacturing apparatus, and all the steps required for refining can be turned by one apparatus. The key feature is that it is flexible and does not use any toxic or dangerous substances in the purification process.
Therefore, the production cost can be produced at a low price of 1/4 or less than the conventional cost, and the equipment cost and installation period of the manufacturing apparatus can be shortened to 1/5 or less.
添付された図面を参照に、本発明の好ましい実施例を詳細に説明する。これに先立ち、本明細書及び請求の範囲に使用された用語や単語は通常的や辞書的な意味で限定して解釈されてはならず、発明者はその自己の発明を最も最善の方法で説明するために、用語の概念を適切に定義することができるという原則に即して本発明の技術的思想に符合する意味と概念で解釈されなければならない。
したがって、本明細書に記載された実施例と図面に図示された構成は、本発明の最も好ましい一実施例に過ぎず、本発明の技術的思想をすべて代弁するものではないので、本出願時点においてこれらを代替することができる多様な均等物と変形例があり得ることを理解されたい。
本発明の2N(99%)の低純度金属シリコンを出発原料として、太陽電池の生産に必要な6〜7N(99.9999〜99.99999%)の高純度に精製する金属シリコンの精製方法は、加熱手段として坩堝内に溶融された金属シリコン表面を局部的に加熱する局部加熱手段を備えて表面に表面温度差を形成する精製方法である。
上記局部加熱手段によって局部的に加熱されて発生する表面温度差は摂氏50度以上の温度差を形成して金属シリコンを精製し、上記局部加熱手段はプラズマ(Plasma)を使用する。
上記プラズマ(Plasma)を断続的に照射して局部的に加熱される温度を調節して金属シリコンを精製し、上記局部加熱手段はプラズマ銃からなり、一つまたは多数個が設けられる。
また、上記坩堝内に供給されて酸素と水素を発生させる不純物除去用物質または上記坩堝内に供給されてモノシラン(SiH4)と酸素と水素を発生させる不純物除去用物質を供給して金属シリコンを精製する。上記不純物除去用物質はO2、O3、H2、H2O、H2O2、HCLO4などが使用され、これらのうち何れか一つを選択して使用する。上記不純物除去用物質を断続的に供給して金属シリコンを精製し、1〜500cc/minの速度で溶融された金属シリコン表面に供給される。
また、上記坩堝を含むチャンバ(Chamber)内の真空度を変化させて金属シリコンを精製することもできる。
また、上記金属シリコンに塩素(Cl)を添加したり、金属シリコンに含有された不純物と反応して塩素(Cl)を形成する物質をさらに添加して金属シリコンを精製する。上記物質はCl2、CCl4、HCl、ClF3などを使用し、これらのうち何れか一つを使用する。
図2は本発明の実施例を図示した金属シリコンの精製装置の断面概略図、図3は図2に図示された金属シリコンの精製装置のA-A線断面図、図4は本発明の金属シリコンの精製装置の部分断面図であり、図5は本発明の金属シリコンの精製装置の部分詳細断面図である。
添付された図面のように、本発明の金属シリコンの精製装置は、大きく分けて、真空が可能なチャンバ(10)と、上記チャンバ(10)内側に設けられて溶融金属シリコンを保存する坩堝(20)と、上記坩堝(20)を支持し、回転と上下移動をする坩堝支持体(30)と、上記坩堝(20)に保存された金属シリコンを加熱して溶融させる加熱手段(40)と、上記坩堝(20)に保存された溶融金属シリコンの上部表面を局部的に加熱する局部加熱手段(50)と、上記坩堝(20)に保存された溶融金属シリコンの上部表面に不純物除去用物質を供給するガス供給管(60)と、上記坩堝(20)の上部と離隔して設けられてガス供給管(60)から供給される不純物除去用物質と坩堝(20)内で発生したガスの流動を案内するガス誘導手段(70)で構成される。
上記真空が可能なチャンバ(10)は真空度を調節することができるものを使用し、一側にはガスを排出するガス排出口(11)が形成され、上記ガス排出口(11)には真空機器(図示しない)が連設されて排出ガスを強制的に高速で排出する。
上記坩堝(20)は金属シリコンを含むように内部空間を有し、下部には局部加熱手段(50)によって坩堝(20)が局部的に加熱されて破損されることを防止するために第1遮断手段(21)が形成される。上記第1遮断手段(21)は熱伝逹を防止する遮断ブロックが使用され、上記遮断ブロックは坩堝と同一の材質または熱伝逹を遮断する能力に優れた材質を使用する。
上記坩堝支持体(30)は坩堝(20)を回転させ、上下移動をさせるように回転と上下移動が可能になるように下部に回転装置と上下移動装置が設けられて回転と上下移動が可能である。
上記坩堝支持体(30)は局部加熱手段(50)によって局部的に加熱されて破損されることを防止するために第2遮断手段(31)が形成され、上記第2遮断手段(31)は熱伝逹を防止するように空間が形成される。上記空間には熱伝逹を遮断する能力に優れた材質の遮断ブロックが設けられる。
上記加熱手段(40)は坩堝(20)に熱を加えて保存された金属シリンダを溶融させ、坩堝(20)に均一に熱を加えるように周囲に設けられる。
上記局部加熱手段(50)はプラズマ(Plasma)を照射するプラズマ銃で形成され、かかる上記局部加熱手段(50)は坩堝(20)内に溶融された金属シリコン(100)の上部表面(100a)の一部分を局部的に加熱する。普通、局部加熱手段(50)のプラズマ銃は上部表面(100a)の中央部分にプラズマを照射するように設けられる。
また、局部加熱手段(50)は一つのプラズマ銃または複数個のプラズマ銃で形成される。
上記ガス供給管(60)は溶融された金属シリコンに含まれている不純物を除去するために液体または気体を供給する管であり、坩堝(20)内の溶融金属シリコンの上部表面に供給するように設けられる。
上記ガス供給管(60)には酸素、水素あるいはモノシラン(SiH4)を生成する液体あるいは気体、あるいはそれらの混合体、または塩素(Cl)または金属シリコンに含有された不純物と反応して塩素(Cl)を形成する物質及び溶融シリコンの酸化を防止するためのアルゴン(Ar)ガスなどが供給される。
上記ガス誘導手段(70)は、図4ないし図5のように、坩堝(20)内の溶融金属シリコンの上部に設けられてガス供給管(60)から供給されるガスと坩堝内の溶融金属シリコンから発生された不純物ガスを誘導して案内する手段である。かかる上記ガス誘導手段(70)はガス供給管(60)から供給されるガスが反応せずに排出されることを防止する。
上記ガス誘導手段(70)は図4のようにガス流れを誘導(制御)する。
上記ガス誘導手段(70)が設けられない場合には、水をガス供給管(60)を通じてチャンバ内に供給しても高温の供給水分は精製すべき溶融シリコンに接触することなく瞬間的に蒸発し、水分による精製作用は実行可能が困難である。
図4に図示されている図面符号gの矢印は排出ガスの流れ方向を示したものであり、図面符号aの矢印は加熱手段(40)の熱の流れを示したものであり、図面符号pはプラズマである。
強力な排気能力を有する真空機器によって強制的かつ高速でガス排出口(11)に排出してガス流れを発生させ、ガス誘導手段(70)によって溶融金属シリコンからの熱によって発生した上昇気流を逆転させて当該ガスを溶融金属シリコン表面に誘導し、効果的に湿潤ガスを接触させる。なおかつこれを効率良くするためには図5に図示されたように高さ(h1、h2)と間隔(s)もまた極めて重要である。
本発明の実施例ではそれぞれh1は100mm、h2は40mm、sは30mmとし、真空機器の排気量は15立方メートル/分にした。
図6は局部加熱手段(50)のプラズマ銃でプラズマを照射する際における溶融金属シリコン表面の瞬間的な温度分布図を図示したものであり、図7は局部加熱手段(50)プラズマ銃でプラズマを照射することで溶融金属シリコンの撹拌状態を図示したものである。
図6のように局部加熱手段(50)のプラズマ銃でプラズマを溶融金属シリコン表面に局部的に照射することで表面温度をプラズマが照射される一部分の温度を高く形成して表面温度差(△t)を形成させる。
このように局部加熱手段(50)のプラズマ銃でプラズマを溶融金属シリコン表面に局部的に加熱させることで表面温度差(△t)と、図7のように坩堝(20)の深さによって温度差が発生し、坩堝内の溶融金属シリコンは撹拌される。
Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Prior to this, the terms and words used in the specification and claims should not be construed in a normal or lexicographic sense, and the inventor shall make his or her invention in the best possible way. In order to explain, the terminology must be interpreted with the meaning and concept consistent with the technical idea of the present invention in accordance with the principle that the concept of term can be appropriately defined.
Therefore, the embodiments described in the present specification and the configurations shown in the drawings are only the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. It should be understood that there can be various equivalents and variations in which these can be substituted.
Using the 2N (99%) low-purity metal silicon of the present invention as a starting material, the method for purifying metal silicon that is purified to the high purity of 6-7N (99.9999-99.99999%) required for solar cell production is as follows: The refining method includes a local heating means for locally heating the surface of the metal silicon melted in the crucible as a heating means, and forms a surface temperature difference on the surface.
The surface temperature difference generated by being locally heated by the local heating means forms a temperature difference of 50 ° C. or more to purify the metal silicon, and the local heating means uses plasma.
Metallic silicon is purified by adjusting the temperature locally heated by intermittently irradiating the plasma (Plasma), and the local heating means comprises a plasma gun, and one or a plurality of them are provided.
Also, the impurity removing material that is supplied into the crucible to generate oxygen and hydrogen or the impurity removing material that is supplied into the crucible to generate monosilane (SiH4), oxygen and hydrogen is supplied to purify the metal silicon. To do. As the substance for removing impurities, O 2 , O 3 , H 2 , H 2 O, H 2 O 2 , HCLO 4 or the like is used, and any one of these is selected and used. The impurity removing material is intermittently supplied to purify the metal silicon, and is supplied to the molten metal silicon surface at a rate of 1 to 500 cc / min.
In addition, metal silicon can be purified by changing the degree of vacuum in a chamber including the crucible.
Further, chlorine (Cl) is added to the metal silicon, or a substance that reacts with impurities contained in the metal silicon to form chlorine (Cl) is further added to purify the metal silicon. As the above material, Cl 2 , CCl 4 , HCl, ClF 3 or the like is used, and any one of them is used.
2 is a schematic cross-sectional view of the apparatus for purifying metal silicon illustrated in the embodiment of the present invention, FIG. 3 is a cross-sectional view taken along line AA of the apparatus for purifying metal silicon illustrated in FIG. 2, and FIG. FIG. 5 is a partial cross-sectional view of the purification apparatus for metal silicon according to the present invention.
As shown in the accompanying drawings, the apparatus for purifying metal silicon according to the present invention is roughly divided into a chamber (10) capable of vacuuming, and a crucible (inside the chamber (10)) for storing molten metal silicon. 20), a crucible support (30) that supports the crucible (20) and rotates and moves up and down, and heating means (40) for heating and melting the metal silicon stored in the crucible (20). A local heating means (50) for locally heating the upper surface of the molten metal silicon stored in the crucible (20); and an impurity removing substance on the upper surface of the molten metal silicon stored in the crucible (20). The gas supply pipe (60) for supplying the gas and the substance for removing impurities and the gas generated in the crucible (20) provided separately from the upper part of the crucible (20) are supplied from the gas supply pipe (60). It comprises gas guiding means (70) for guiding the flow.
The chamber (10) capable of adjusting the vacuum uses a chamber whose degree of vacuum can be adjusted, and a gas discharge port (11) for discharging gas is formed on one side, and the gas discharge port (11) has a gas discharge port (11). A vacuum device (not shown) is connected to forcibly exhaust the exhaust gas at high speed.
The crucible (20) has an internal space so as to contain metallic silicon, and a lower portion of the crucible (20) is first heated to prevent the crucible (20) from being locally heated and damaged by the local heating means (50). A blocking means (21) is formed. The first blocking means (21) uses a blocking block for preventing heat transfer, and the blocking block is made of the same material as the crucible or a material excellent in ability to block heat transfer.
The crucible support (30) rotates and moves up and down to rotate the crucible (20) so that it can be rotated and moved up and down. It is.
In order to prevent the crucible support (30) from being locally heated by the local heating means (50) and being damaged, second blocking means (31) is formed, and the second blocking means (31) A space is formed to prevent heat transfer. The space is provided with a blocking block made of a material having an excellent ability to block heat transfer.
The heating means (40) is provided at the periphery so as to apply heat to the crucible (20) to melt the stored metal cylinder and to uniformly apply heat to the crucible (20).
The local heating means (50) is formed by a plasma gun that irradiates plasma, and the local heating means (50) is an upper surface (100a) of the metal silicon (100) melted in the crucible (20). A portion of is heated locally. Usually, the plasma gun of the local heating means (50) is provided so as to irradiate the central portion of the upper surface (100a) with plasma.
The local heating means (50) is formed by one plasma gun or a plurality of plasma guns.
The gas supply pipe (60) is a pipe for supplying a liquid or a gas to remove impurities contained in the molten metal silicon, and is supplied to the upper surface of the molten metal silicon in the crucible (20). Provided.
The
As shown in FIGS. 4 to 5, the gas guiding means (70) is provided above the molten metal silicon in the crucible (20) and supplied from the gas supply pipe (60) and the molten metal in the crucible. It is a means for guiding and guiding an impurity gas generated from silicon. The gas guiding means (70) prevents the gas supplied from the gas supply pipe (60) from being discharged without reacting.
The gas guiding means 70 induces (controls) the gas flow as shown in FIG.
In the case where the gas guiding means (70) is not provided, even if water is supplied into the chamber through the gas supply pipe (60), the high-temperature supply water is instantaneously evaporated without contacting the molten silicon to be purified. However, it is difficult to carry out the purification effect by moisture.
4 indicates the flow direction of the exhaust gas, and the arrow of the reference symbol a indicates the heat flow of the heating means (40). Is a plasma.
The gas flow is forcibly discharged at high speed by a vacuum device having a powerful exhaust capability to generate a gas flow, and the upward flow generated by the heat from the molten metal silicon is reversed by the gas guiding means (70). Then, the gas is guided to the surface of the molten metal silicon, and the wet gas is effectively contacted. In order to make this efficient, the height (h1, h2) and the interval (s) are also extremely important as shown in FIG.
In the examples of the present invention, h1 was 100 mm, h2 was 40 mm, s was 30 mm, and the displacement of the vacuum equipment was 15 cubic meters / minute.
6 shows an instantaneous temperature distribution diagram on the surface of the molten metal silicon when the plasma is irradiated by the plasma gun of the local heating means (50), and FIG. 7 shows the plasma generated by the local heating means (50) plasma gun. The stirring state of molten metal silicon is illustrated by irradiating.
As shown in FIG. 6, the surface temperature difference (Δ) is formed by increasing the surface temperature of the part irradiated with plasma by locally irradiating the surface of the molten metal silicon with the plasma gun of the local heating means (50). t) is formed.
In this way, the plasma is locally heated on the surface of the molten metal silicon by the plasma gun of the local heating means (50), so that the temperature depends on the surface temperature difference (Δt) and the depth of the crucible (20) as shown in FIG. A difference occurs and the molten metal silicon in the crucible is agitated.
加熱手段(40)で熱を加えて坩堝(20)内の金属シリコンを溶融させる。
上記坩堝(20)内の溶融された金属シリコン(100)の温度は摂氏1,550度であり、ここに局部加熱手段(50)のプラズマ銃に印加電力20kWを印加させてプラズマを溶融金属シリコンの上部表面に照射する。この時、上部表面(100a)の最高温度は摂氏 3,000度である。
また、ガス供給管(60)に反応して酸素、水素あるいはモノシラン(SiH4)を生成する液体、あるいは気体あるいはそれらの混合体を供給した。例えば、水あるいは湿潤ガスなどを供給する。
温度については、図6のように摂氏1,550度から摂氏3,000度まで坩堝中央の温度が変化していることを表示しており、表面温度差(△t)は摂氏1,450である。
また、ガス供給管(60)に溶融シリコンの酸化を防止するためにArガスを供給する。
上記のように溶融金属シリコン(100)の上部表面(100a)は摂氏1,550から摂氏3,000度と多様に分布しており、かかる温度分布は精製(純化)工程に対して極めて大きい意味を有する。すなわち、精製のために除去しなければならない不純物元素が様々な種類があり、それぞれの不純物元素は不純物元素固有の温度条件によって化学反応を起こし、蒸発、変態、化合、混合などによって気化され、浮遊物になって溶融シリコンの表面に存在する。
本発明の金属シリコンの精製方法では、溶融シリコン内部の精製に対して有用なガスと化学物が供給されないという欠点を有する。すなわち、溶融シリコン表面が精製されても坩堝内部の溶融シリコン含有不純物の分布が均一にならない。
かかる問題を解決するためには、溶融金属シリコンの混合及び撹拌が必要である。
本発明は図7に示したように温度勾配の適用とガス流入による精製を利用した。坩堝(20)下部分の温度は溶融金属シリコンの温度と同一の摂氏1,450度であり、上部表面(100a)はプラズマの照射瞬間温度で摂氏3,000度であり、プラズマと供給されるガス圧力によって中央では凹んで凹入形状になる。
このような様々な要件によって総合的に矢印のように溶融金属シリコンは循環して撹拌される。ここでは1個の温度勾配を表示したが、プラズマを照射する局部加熱手段(50)とガス供給管(60)を複数を組み合わせて使用することも可能である。
プラズマの照射による溶融シリコンの温度上昇を少なくするため、そして添加液体の効果を持続的に得るために断続する必要性があるので、このようなことを反復動作して適用する。もちろん複数の照射元を組み合わせて使用することも問題がない。
Heat is applied by the heating means (40) to melt the metal silicon in the crucible (20).
The temperature of the molten metal silicon (100) in the crucible (20) is 1,550 degrees Celsius, and an electric power of 20 kW is applied to the plasma gun of the local heating means (50) to apply the plasma to the molten metal silicon. Irradiate the upper surface. At this time, the maximum temperature of the upper surface (100a) is 3,000 degrees Celsius.
In addition, liquid, gas, or a mixture thereof that generates oxygen, hydrogen, or monosilane (SiH4) in response to the gas supply pipe (60) was supplied. For example, water or wet gas is supplied.
Regarding the temperature, the temperature at the center of the crucible is changed from 1,550 degrees Celsius to 3,000 degrees Celsius as shown in FIG. 6, and the surface temperature difference (Δt) is 1,450 degrees Celsius. is there.
Further, Ar gas is supplied to the gas supply pipe (60) in order to prevent oxidation of the molten silicon.
As described above, the upper surface (100a) of the molten metal silicon (100) has various distributions ranging from 1,550 degrees Celsius to 3,000 degrees Celsius, and this temperature distribution has an extremely large meaning for the purification (purification) process. Have That is, there are various types of impurity elements that must be removed for purification. Each impurity element undergoes a chemical reaction depending on the temperature conditions specific to the impurity element, and is vaporized by evaporation, transformation, compounding, mixing, etc. Present on the surface of the molten silicon.
The method for purifying metal silicon according to the present invention has a drawback that gas and chemicals useful for purification inside molten silicon are not supplied. That is, even if the surface of the molten silicon is purified, the distribution of the molten silicon-containing impurities in the crucible is not uniform.
In order to solve such a problem, mixing and stirring of molten metal silicon are necessary.
The present invention utilized the application of temperature gradient and purification by gas inflow as shown in FIG. The temperature of the lower part of the crucible (20) is 1,450 degrees Celsius, which is the same as the temperature of the molten metal silicon, and the upper surface (100a) is 3,000 degrees Celsius at the plasma irradiation instantaneous temperature, and is supplied with the plasma. Due to the gas pressure, it is recessed at the center and becomes a recessed shape.
Due to these various requirements, the molten metal silicon is circulated and agitated as indicated by arrows. Here, one temperature gradient is displayed, but it is also possible to use a combination of a plurality of local heating means (50) for irradiating plasma and a gas supply pipe (60).
In order to reduce the temperature rise of the molten silicon due to the plasma irradiation and to continuously obtain the effect of the added liquid, this is applied repeatedly. Of course, there is no problem in using a plurality of irradiation sources in combination.
10 : チャンバ
20 : 坩堝
21 : 第1遮断手段
30 : 坩堝支持体
31 : 第2遮断手段
40 : 加熱手段
50 : 局部加熱手段
60 : ガス供給管
70 : ガス誘導手段
10: chamber 20: crucible 21: first blocking means 30: crucible support 31: second blocking means 40: heating means 50: local heating means 60: gas supply pipe 70: gas guiding means
Claims (17)
坩堝内の金属シリコン表面を局部的に加熱する局部加熱手段を備えて表面に表面温度差を形成することを特徴とする金属シリコンの精製方法。 Using low-purity metallic silicon as a starting material, when purifying to the purity required for solar cell production,
A method for purifying metal silicon, comprising a local heating means for locally heating the surface of the metal silicon in the crucible to form a surface temperature difference on the surface.
上記チャンバ(10)内側に設けられて溶融金属シリコンを保存する坩堝(20)と;
上記坩堝(20)を支持し、回転と上下移動をする坩堝支持体(30)と;
上記坩堝(20)に保存された金属シリコンを加熱して溶融させる加熱手段(40)と;
上記坩堝(20)に保存された溶融金属シリコンの上部表面を局部的に加熱する局部加熱手段(50)と;
上記坩堝(20)に保存された溶融金属シリコンの上部表面に不純物除去用物質を供給するガス供給管(60)を含む金属シリコンの精製装置。 A chamber (10) capable of vacuum;
A crucible (20) provided inside the chamber (10) for storing molten metal silicon;
A crucible support (30) for supporting the crucible (20) and rotating and moving up and down;
Heating means (40) for heating and melting the metal silicon stored in the crucible (20);
Local heating means (50) for locally heating the upper surface of the molten metal silicon stored in the crucible (20);
An apparatus for purifying metal silicon, comprising a gas supply pipe (60) for supplying an impurity removing substance to the upper surface of the molten metal silicon stored in the crucible (20).
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020090045687A KR100966755B1 (en) | 2009-05-25 | 2009-05-25 | Method and apparatus for refining silicon |
Publications (1)
Publication Number | Publication Date |
---|---|
JP2010269992A true JP2010269992A (en) | 2010-12-02 |
Family
ID=42370555
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2009176506A Pending JP2010269992A (en) | 2009-05-25 | 2009-07-29 | Method and apparatus for refining metallic silicon |
Country Status (2)
Country | Link |
---|---|
JP (1) | JP2010269992A (en) |
KR (1) | KR100966755B1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8236266B2 (en) | 2010-07-21 | 2012-08-07 | Masahiro Hoshino | Method and apparatus for purifying metallurgical silicon for solar cells |
US8236265B2 (en) | 2010-02-12 | 2012-08-07 | Masahiro Hoshino | Method for purifying metallurgical silicon for solar cells |
JP2013510794A (en) * | 2009-11-16 | 2013-03-28 | 政宏 星野 | Method for purifying metallic silicon |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR101079618B1 (en) | 2009-08-11 | 2011-11-04 | (주)원익머트리얼즈 | Apparatus for refining silicon |
CN102834935B (en) * | 2010-08-16 | 2015-06-03 | 星野政宏 | Apparatus and method for purifying metallurgical silicon for solar cells |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH04228414A (en) * | 1990-05-30 | 1992-08-18 | Kawasaki Steel Corp | Purification of silicon and apparatus therefor |
JPH04338108A (en) * | 1991-05-10 | 1992-11-25 | Kawasaki Steel Corp | Method and device for refining silicon |
JPH05262512A (en) * | 1992-03-17 | 1993-10-12 | Kawasaki Steel Corp | Purification of silicon |
JPH06115922A (en) * | 1992-10-07 | 1994-04-26 | Kawasaki Steel Corp | Method for purifying silicon |
JPH10212113A (en) * | 1997-01-28 | 1998-08-11 | Kawasaki Steel Corp | Method for removing boron from metal silicon |
JP2002097098A (en) * | 2000-09-26 | 2002-04-02 | Shin Etsu Handotai Co Ltd | Production of silicon single crystal and apparatus for growing semiconductor single crystal |
JP2002321997A (en) * | 2001-04-20 | 2002-11-08 | Shin Etsu Handotai Co Ltd | Apparatuses for making silicon single crystal and method for making silicon single crystal using the same |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH075288B2 (en) * | 1985-07-31 | 1995-01-25 | フォトワット・インタナショナル・ソシエテ・アノニム | Method for purifying divided silicon under plasma |
JP2003277040A (en) | 2002-03-19 | 2003-10-02 | Sharp Corp | Method of purifying silicon and solar cell manufactured by using silicon purified by method thereof |
JP2007326749A (en) | 2006-06-08 | 2007-12-20 | Sharp Corp | Silicon purification apparatus and silicon purification method |
-
2009
- 2009-05-25 KR KR1020090045687A patent/KR100966755B1/en not_active IP Right Cessation
- 2009-07-29 JP JP2009176506A patent/JP2010269992A/en active Pending
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH04228414A (en) * | 1990-05-30 | 1992-08-18 | Kawasaki Steel Corp | Purification of silicon and apparatus therefor |
JPH04338108A (en) * | 1991-05-10 | 1992-11-25 | Kawasaki Steel Corp | Method and device for refining silicon |
JPH05262512A (en) * | 1992-03-17 | 1993-10-12 | Kawasaki Steel Corp | Purification of silicon |
JPH06115922A (en) * | 1992-10-07 | 1994-04-26 | Kawasaki Steel Corp | Method for purifying silicon |
JPH10212113A (en) * | 1997-01-28 | 1998-08-11 | Kawasaki Steel Corp | Method for removing boron from metal silicon |
JP2002097098A (en) * | 2000-09-26 | 2002-04-02 | Shin Etsu Handotai Co Ltd | Production of silicon single crystal and apparatus for growing semiconductor single crystal |
JP2002321997A (en) * | 2001-04-20 | 2002-11-08 | Shin Etsu Handotai Co Ltd | Apparatuses for making silicon single crystal and method for making silicon single crystal using the same |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2013510794A (en) * | 2009-11-16 | 2013-03-28 | 政宏 星野 | Method for purifying metallic silicon |
US8673073B2 (en) | 2009-11-16 | 2014-03-18 | Masahiro Hoshino | Methods for purifying metallurgical silicon |
US8236265B2 (en) | 2010-02-12 | 2012-08-07 | Masahiro Hoshino | Method for purifying metallurgical silicon for solar cells |
US8461487B2 (en) | 2010-02-12 | 2013-06-11 | Masahiro Hoshino | Apparatus for purifying metallurgical silicon for solar cells |
US8524188B2 (en) | 2010-02-12 | 2013-09-03 | Masahiro Hoshino | Method for purifying metallurgical silicon for solar cells |
US8236266B2 (en) | 2010-07-21 | 2012-08-07 | Masahiro Hoshino | Method and apparatus for purifying metallurgical silicon for solar cells |
US8501140B2 (en) | 2010-07-21 | 2013-08-06 | Masahiro Hoshino | Method and apparatus for purifying metallurgical silicon for solar cells |
Also Published As
Publication number | Publication date |
---|---|
KR100966755B1 (en) | 2010-06-29 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5805110B2 (en) | Apparatus and method for purifying metallic silicon for solar cells | |
EP2987771A1 (en) | Fluidized bed reactor and method thereof for preparing high-purity granular polycrystalline silicon | |
JP5886831B2 (en) | Generation of single crystal semiconductor materials | |
JP5657687B2 (en) | Method for purifying metallic silicon | |
JP2010269992A (en) | Method and apparatus for refining metallic silicon | |
TWI403461B (en) | Method and apparatus for improving yield and yield of metallurgical silicon | |
TW201009139A (en) | Direct silicon or reactive metal casting | |
JP2012051788A (en) | Process for production of polycrystalline silicon | |
KR20140114440A (en) | Method for purification of silicon | |
JP2007145663A (en) | Method for producing high purity polycrystalline silicon | |
JP2008260675A (en) | Apparatus and method for manufacturing high purity polycrystalline silicon | |
CN104918883B (en) | For the method for deposit polycrystalline silicon | |
JP4692324B2 (en) | High purity polycrystalline silicon production equipment | |
Karabanov et al. | Mathematical modeling and experimental research of the method of plasma chemical purification of metallurgical-grade silicon | |
RU2465201C1 (en) | Method of producing polycrystalline silicon ingots | |
CA2938453C (en) | Method for producing polycrystalline silicon | |
JP5155708B2 (en) | Method for hydrogen reduction of chlorosilane-containing gas and apparatus for hydrogen reduction of chlorosilanes | |
US11560316B2 (en) | Process and apparatus for removal of impurities from chlorosilanes | |
JP5542031B2 (en) | Polycrystalline silicon manufacturing method and polycrystalline silicon manufacturing system | |
KR101079618B1 (en) | Apparatus for refining silicon | |
JP2008100857A (en) | Apparatus and method for refining metal | |
KR101590679B1 (en) | Apparatus for generating dual plasma and method of producing polysilicon using same | |
KR101186986B1 (en) | Mass production method for pure silicon | |
CN102742034B (en) | The method of purification of metalluragical silicon | |
KR101871019B1 (en) | Apparatus for producing polysilicon and preparation of polysilicon using same |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20090729 |
|
A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20100208 |
|
A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20120224 |
|
A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20120313 |
|
A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20120814 |