JPH0710679A - Production of single crystal - Google Patents
Production of single crystalInfo
- Publication number
- JPH0710679A JPH0710679A JP15488093A JP15488093A JPH0710679A JP H0710679 A JPH0710679 A JP H0710679A JP 15488093 A JP15488093 A JP 15488093A JP 15488093 A JP15488093 A JP 15488093A JP H0710679 A JPH0710679 A JP H0710679A
- Authority
- JP
- Japan
- Prior art keywords
- crystal
- single crystal
- seed
- seed crystal
- crucible
- 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.)
- Granted
Links
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- Crystals, And After-Treatments Of Crystals (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は単結晶の製造方法、特に
はブリッジマン法により、生産性よく単結晶を育成させ
る単結晶の製造方法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a single crystal, and more particularly to a method for producing a single crystal by the Bridgman method for growing the single crystal with high productivity.
【０００２】[0002]
【従来の技術】ブリッジマン法は公知のものであるが、
これは例えば図３に示した装置で行われる。図２はブリ
ッジマン法による単結晶成長方法の断面図を示したもの
であり、この電気炉11の中には白金ルツボ12が設置され
ており、この白金ルツボに仕込まれた多結晶体は図示さ
れていないヒーター部で加熱されて融液13としてルツボ
内に保持されている。この白金ルツボにはその下方に種
管14が設置されており、この先端部に種結晶15が挿入さ
れている。The Bridgman method is known, but
This is done, for example, with the device shown in FIG. FIG. 2 shows a cross-sectional view of a single crystal growth method by the Bridgman method. A platinum crucible 12 is installed in the electric furnace 11, and a polycrystalline substance charged in the platinum crucible is shown in the figure. It is heated by a heater part which is not heated and held in the crucible as a melt 13. A seed tube 14 is installed below the platinum crucible, and a seed crystal 15 is inserted at the tip of the seed tube 14.
【０００３】単結晶の成長は、この種結晶上部の温度を
結晶の融点よりやや高めに保持し、種結晶の一部を溶融
することで融液13を種結晶に完全に接触させ、これをよ
り低温に保持されている炉11の下方に育成する結晶に応
じた降下速度で降下させると、融液がルツボ12の中で単
結晶に育成されるので、降下後、炉の温度を下げてこの
白金ルツボを取り出し白金を破って単結晶を取り出せば
よい。In the growth of a single crystal, the temperature of the upper portion of the seed crystal is kept slightly higher than the melting point of the crystal and a part of the seed crystal is melted to bring the melt 13 into complete contact with the seed crystal. When the temperature is lowered at a lowering rate according to the crystal to be grown below the furnace 11 which is held at a lower temperature, the melt is grown into a single crystal in the crucible 12, so after the lowering, the temperature of the furnace is lowered. The platinum crucible is taken out, the platinum is broken, and the single crystal is taken out.
【０００４】[0004]
【発明が解決しようとする課題】このブリッジマン法に
使われるルツボの形状は通常は図２に示したように胴体
部とその下を絞った部分および種管の部分からなってい
るが、育成単結晶の有効長を大きくして生産性を上げる
ために、種管の部分を無くした平底のルツボを用いるこ
とも提案されている（特願平4-80430 号明細書参照）。
また、さらにこの平底を無くしたルツボを用いると経済
的である。しかし、このような底の無いルツボを用いる
と種結晶の厚さが大きくなるために育成された結晶にク
ラックが入るという問題が起こるし、これを薄くすると
溶解のおそれがある。The shape of the crucible used in the Bridgman method is usually composed of a body portion, a lower portion thereof and a seed tube portion as shown in FIG. It has also been proposed to use a flat-bottomed crucible without a seed tube in order to increase the effective length of a single crystal and increase productivity (see Japanese Patent Application No. 4-80430).
Further, it is economical to use the crucible without the flat bottom. However, when such a crucible having no bottom is used, the thickness of the seed crystal becomes large, so that the grown crystal has a problem of cracking. If the crucible is made thin, melting may occur.
【０００５】[0005]
【課題を解決するための手段】本発明はこのような不
利、問題点を解決したブリッジマン法による単結晶の製
造方法に関するものであり、これはブリッジマン法で融
液から種結晶を用いて単結晶を成長させる方法におい
て、結晶成長方向に対しほぼ垂直な方向に種結晶が複数
に分割されていることを特徴とするものである。The present invention relates to a method for producing a single crystal by the Bridgman method, which solves the above disadvantages and problems, by using a seed crystal from a melt by the Bridgman method. In the method for growing a single crystal, the seed crystal is divided into a plurality of pieces in a direction substantially perpendicular to the crystal growth direction.
【０００６】すなわち、本発明者らはブリッジマン法に
よる単結晶育成方法について種々検討した結果、これに
ついては種結晶直下の材料と結晶の成長速度および結晶
中のクラックの有無についての実験を行ない、結晶にク
ラックを起こさずに、かつ結晶の成長速長速度を上げる
には、ブリッジマン法で融液から種結晶を用いて単結晶
を成長させる方法において、結晶成長方向に対してほぼ
垂直な方向に種結晶を複数に分割すればよいということ
を見出して本発明を完成させた。以下にこれをさらに詳
述する。That is, the present inventors have conducted various studies on a single crystal growth method by the Bridgman method, and as a result, conducted experiments on the material immediately below the seed crystal, the growth rate of the crystal, and the presence or absence of cracks in the crystal. In order to increase the growth rate of the crystal without causing cracks in the crystal, in the method of growing a single crystal from a melt by the Bridgman method using a seed crystal, a direction almost perpendicular to the crystal growth direction The present invention has been completed by finding out that it is sufficient to divide the seed crystal into a plurality of pieces. This will be described in more detail below.
【０００７】[0007]
【作用】本発明は単結晶の製造方法に関するものであ
り、これは前記したようにブリッジマン法で単結晶を成
長させる方法において、結晶成長方向に対してほぼ垂直
に結晶が複数に分割されていることを特徴とするもので
あるが、これによれば得られる単結晶にクラックが発生
せず、結晶の成長速度も上げることができるという有利
性が与えられる。The present invention relates to a method for producing a single crystal, which is a method of growing a single crystal by the Bridgman method as described above, in which the crystal is divided into a plurality of crystals substantially perpendicular to the crystal growth direction. According to this, there is an advantage that a crack does not occur in the obtained single crystal and the growth rate of the crystal can be increased.
【０００８】本発明による単結晶の製造方法は、ブリッ
ジマン法で単結晶を製造する方法の改良に関するもので
あり、これは結晶成長方向に対してほぼ垂直方向に種結
晶を複数に分割して配置することを特徴とするものであ
る。したがって、これは例えば前記した図２における種
管14の先端部に挿入されている種結晶15を円板状のもの
としてこれを複数枚重積したものとすればよいが、これ
については図２における種管14の内径ａとルツボ12の胴
体部の内径ｂとの比ａ／ｂを 1.0として、底の無いルツ
ボを用いる場合によい。The method for producing a single crystal according to the present invention relates to an improvement of the method for producing a single crystal by the Bridgman method, which is to divide a seed crystal into a plurality of pieces in a direction substantially perpendicular to the crystal growth direction. It is characterized by being arranged. Therefore, for example, the seed crystal 15 inserted into the tip portion of the seed tube 14 in FIG. 2 described above may be formed into a disc shape and a plurality of the seed crystals 15 may be stacked. The ratio a / b of the inner diameter a of the seed tube 14 and the inner diameter b of the body portion of the crucible 12 in 1 is set to 1.0, which is preferable when a crucible having no bottom is used.
【０００９】図１は底の無いルツボを用いた場合の本発
明による単結晶製造方法の縦断面図を示したものである
が、図１における電気炉内のアルミナ炉心管の中には白
金ルツボ２が設置されており、このルツボ２の中には図
示されていないヒーター部での加熱で溶融された多結晶
体の融液３が保持されているが、この白金ルツボ２の下
方には板状の種結晶５−１、５−２、５−３が結晶成長
方向とほぼ垂直な方向に分割して堆積されている。FIG. 1 is a vertical sectional view of a method for producing a single crystal according to the present invention when a bottomless crucible is used. In the alumina crucible in the electric furnace shown in FIG. 2 is installed, and a melt 3 of a polycrystalline body melted by heating in a heater part (not shown) is held in the crucible 2. Below the platinum crucible 2, a plate is provided. Seed crystals 5-1, 5-2, and 5-3 are divided and deposited in a direction substantially perpendicular to the crystal growth direction.
【００１０】したがって、ブリッジマン法にしたがって
この融液２を種結晶５と接触させ、これをより低温に保
持されている炉１の下方に結晶育成に応じた降下速度で
降下させると単結晶がこのルツボ２の中で成育されるの
であるが、この種結晶が円板状のものを分割して積み重
ねたものとされているので、この場合には単結晶にクラ
ックが発生しなくなるし、種結晶が溶解するおそれもな
いので、これによれば結晶も収率がよく、またルツボも
低コストとすることができるという有利性が与えられ
る。Therefore, when the melt 2 is brought into contact with the seed crystal 5 according to the Bridgman method and is lowered at a lowering rate according to crystal growth below the furnace 1 which is kept at a lower temperature, a single crystal is formed. The seed crystal is grown in this crucible 2, but since this seed crystal is formed by dividing and stacking disc-shaped ones, in this case, the single crystal does not crack, and the seed crystal does not grow. Since there is no possibility that the crystals will be dissolved, this provides the advantage that the crystals can be obtained in a high yield and the crucible can be manufactured at low cost.
【００１１】なお、本発明によって単結晶を製造すると
きに使用する種結晶の大きさは任意とされるが、内径が
80mmの白金ルツボを使用するとき、この種結晶は直径が
79〜79.5mmのものとすればよいが、このものはその厚さ
が32mm以上のものとすると得られる単結晶にクラックが
発生するようになるので、厚さが10〜20mmの円板状のも
のとするがよい。この円板状の種結晶は１枚では融液も
れなどのトラブルの原因となるので、少なくとも２枚以
上、好ましくは３枚以上を単結晶の結晶成長方向に対し
て垂直な方向に積み重ねることがよいが、この場合には
種結晶の一部を溶かすことで種付けを行なうので、炉の
ピーク温度は目的とする単結晶の融点よりも50〜 200℃
高い温度とすることがよく、最下端の種結晶の温度は種
結晶が溶けるのを防止するために、目的とする単結晶の
融点よりも20〜 100℃低い温度とすることがよい。The size of the seed crystal used for producing a single crystal according to the present invention is arbitrary, but the inner diameter is
When using an 80 mm platinum crucible, this seed crystal has a diameter of
It should be 79 to 79.5 mm, but if this thickness is 32 mm or more, cracks will occur in the obtained single crystal, so a disk shape with a thickness of 10 to 20 mm It should be one. This disc-shaped seed crystal causes troubles such as melt leakage, so at least two or more, preferably three or more, should be stacked in a direction perpendicular to the crystal growth direction of the single crystal. However, in this case, seeding is performed by melting a part of the seed crystal, so the peak temperature of the furnace is 50 to 200 ° C higher than the melting point of the target single crystal.
The temperature is preferably high, and the temperature of the seed crystal at the lowest end is preferably 20 to 100 ° C. lower than the melting point of the target single crystal in order to prevent the seed crystal from melting.
【００１２】本発明による単結晶の製造はブリッジマン
法により製造されるすべての物質に対して適用すること
ができるので、これによればLiTaO3、LiNbO3、ＢＧＯ、
Li2B4O7 などの単結晶を有利に製造することができる。Since the production of the single crystal according to the present invention can be applied to all materials produced by the Bridgman method, according to this, LiTaO 3 , LiNbO 3 , BGO,
A single crystal such as Li 2 B 4 O 7 can be advantageously produced.
【００１３】[0013]
【実施例】つぎに本発明の実施例、比較例をあげる。 実施例１、比較例１ 内径80mmで長さが 180mmの円筒状白金ルツボの底部に直
径79mmで厚さが20mmの円盤状の種結晶を３枚積み重ね、
その上に純度４Ｎの炭酸リチウムと純度４Ｎの五酸化ニ
オブとを１：１（モル比）の割合で混合したのち、 1,0
00℃で仮焼した原料を2,300g入れ、種結晶を完全に溶か
さないように炉のピーク温度を 1,350℃とし、最上部の
20mmの種結晶を一部溶かしたのち、結晶成長を始め、こ
れを降下速度 0.5mm／時で結晶を育成し、育成終了後、
白金ルツボを破いて種結晶の厚みと育成したニオブ酸リ
チウム単結晶中のクラックの有無をしらべたところ、種
結晶の厚みは上部から10mmと20mm、20mmであり、得られ
たニオブ酸リチウム単結晶にはクラックのないことが確
認された。EXAMPLES Next, examples and comparative examples of the present invention will be described. Example 1, Comparative Example 1 Three disc-shaped seed crystals having a diameter of 79 mm and a thickness of 20 mm are stacked on the bottom of a cylindrical platinum crucible having an inner diameter of 80 mm and a length of 180 mm,
Lithium carbonate having a purity of 4N and niobium pentoxide having a purity of 4N were mixed thereon at a ratio of 1: 1 (molar ratio), and then 1,0
Put 2,300g of raw material calcined at 00 ℃, and set the peak temperature of the furnace to 1,350 ℃ so that the seed crystal is not completely melted.
After partially melting a 20 mm seed crystal, crystal growth was started, and this was grown at a descent rate of 0.5 mm / hour.
When the platinum crucible was broken and the thickness of the seed crystal and the presence or absence of cracks in the grown lithium niobate single crystal were examined, the thickness of the seed crystal was 10 mm, 20 mm, and 20 mm from the top, and the obtained lithium niobate single crystal was obtained. It was confirmed that there was no crack.
【００１４】しかし、比較のためにこの種結晶を直径が
79mmで厚みが50mmの円盤状のもの１枚のみとし、種結晶
近傍の温度をニオブ酸リチウム結晶よりやや高目として
種結晶を一部溶解したほかは実施例と同様に処理してニ
オブ酸リチウム単結晶を作り、この単結晶を取り出して
種結晶の厚みと得られたニオブ酸リチウム単結晶のクラ
ックの有無をしらべたところ、種結晶の厚みは45mmであ
り、この単結晶には結晶全体にクラックが入っていた。However, for comparison, this seed crystal has a diameter of
Lithium niobate was treated in the same manner as in Example except that only one disc-shaped member having a thickness of 79 mm and a thickness of 50 mm was used, and the temperature in the vicinity of the seed crystal was slightly higher than that of the lithium niobate crystal to partially dissolve the seed crystal. A single crystal was made, and when this single crystal was taken out and examined for the thickness of the seed crystal and the presence or absence of cracks in the obtained lithium niobate single crystal, the thickness of the seed crystal was 45 mm, and this single crystal had It had cracks.
【００１５】実施例２、比較例２ 純度４Ｎの酸化ビスマスと純度４Ｎの二酸化ゲルマニウ
ムとを２：３（モル比）の割合で混合したのち、 900℃
で仮焼し、内径90mmの筒状の底の無い白金製容器の下に
直径89.5mmで厚さ10mmの種結晶を３枚置き、この上に仮
焼した原料を入れ、種結晶を完全に溶かさないように炉
のピーク温度を 1,200℃とし、種結晶近傍の温度をＢＧ
Ｏ結晶の融点よりやや高目として、育成開始位置を変え
て、種結晶を一部溶解し、降下速度1.0mm/hrで結晶を育
成し、育成後白金ルツボを破き種結晶の厚みと育成結晶
中のクラックの有無を調べたところ、クラックの見られ
ない結晶が得られた。同様の実験を種結晶の厚さを40mm
とし結晶育成を行ったところ、育成結晶にはクラックが
はいった。同様の条件でルツボ形状を底のあるものとし
た以外は同じとして行った結果、育成結晶にはクラック
がみられなかったが、気泡状の介在物が多い結晶とな
り、降下速度を1.0mm/hrから0.5mm/hrとしたところ気泡
状の介在物が消失した。Example 2 and Comparative Example 2 Bismuth oxide having a purity of 4N and germanium dioxide having a purity of 4N were mixed at a ratio of 2: 3 (molar ratio), and then 900 ° C.
Calcined, put three seed crystals with a diameter of 89.5 mm and a thickness of 10 mm under a cylindrical bottomless platinum container with an inner diameter of 90 mm, put the calcined raw material on this, and seed crystals completely The furnace peak temperature was set to 1200 ° C so that it would not melt, and the temperature near the seed crystal was set to BG.
Slightly higher than the melting point of O crystal, the growth start position is changed, the seed crystal is partially dissolved, and the crystal is grown at a descending rate of 1.0 mm / hr. After growth, the platinum crucible is broken and the thickness and growth of the seed crystal is increased. When the presence or absence of cracks in the crystal was examined, a crystal without any crack was obtained. Seed crystal thickness 40mm
When the crystal was grown, cracks appeared in the grown crystal. As a result of performing the same except that the crucible shape has a bottom under the same conditions, no cracks were observed in the grown crystal, but it became a crystal with many bubble-like inclusions, and the descending speed was 1.0 mm / hr. At 0.5 mm / hr, bubble-like inclusions disappeared.
【００１６】[0016]
【発明の効果】本発明は単結晶の製造方法に関するもの
であり、これは前記したようにブリッジマン法で融液か
ら種結晶を用いて単結晶を成長させる方法において、結
晶成長方向に対しほぼ垂直な方法に種結晶が分割されて
いることを特徴とするものであるが、これによれば目的
とする単結晶にクラックを起さずに、結晶の成長速度を
上げることができるという有利性が与えられる。さら
に、この方法によれば底の無いルツボを用いることがで
きるために経済的である。Industrial Applicability The present invention relates to a method for producing a single crystal, which is a method for growing a single crystal from a melt by using a seed crystal by the Bridgman method, as described above. It is characterized in that the seed crystal is divided in a vertical method, which is advantageous in that the growth rate of the crystal can be increased without causing cracks in the target single crystal. Is given. Furthermore, this method is economical because a crucible without a bottom can be used.
【図１】本発明による単結晶の製造方法の縦断面図を示
したものである。FIG. 1 is a vertical sectional view showing a method for producing a single crystal according to the present invention.
【図２】公知のブリッジマン法による単結晶成長方法の
縦断面図を示したものである。FIG. 2 is a vertical cross-sectional view of a known single crystal growth method by the Bridgman method.
【図３】公知のブリッジマン法による単結晶成長方法の
縦断面図を示したものである。FIG. 3 is a vertical cross-sectional view of a known single crystal growth method by Bridgman method.
１，11…電気炉、 ２，12…白金ルツボ、３，13…融
液、 ５，５−１，５−２，５−３…種結晶、14…種
管、 15…種結晶。1, 11 ... Electric furnace, 2, 12 ... Platinum crucible, 3, 13 ... Melt solution, 5,5-1, 5-2, 5-3 ... Seed crystal, 14 ... Seed tube, 15 ... Seed crystal.
Claims (2)
単結晶を成長させる方法において、結晶成長方向に対し
ほぼ垂直な方向に種結晶が分割されていることを特徴と
する単結晶の製造方法。1. A method for growing a single crystal from a melt by a Bridgman method using a seed crystal, wherein the seed crystal is divided in a direction substantially perpendicular to the crystal growth direction. Production method.
法。2. A method for producing a single crystal using a bottomless crucible.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP05154880A JP3115156B2 (en) | 1993-06-25 | 1993-06-25 | Single crystal manufacturing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP05154880A JP3115156B2 (en) | 1993-06-25 | 1993-06-25 | Single crystal manufacturing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0710679A true JPH0710679A (en) | 1995-01-13 |
| JP3115156B2 JP3115156B2 (en) | 2000-12-04 |
Family
ID=15593974
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP05154880A Expired - Fee Related JP3115156B2 (en) | 1993-06-25 | 1993-06-25 | Single crystal manufacturing method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3115156B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2891731A4 (en) * | 2012-08-29 | 2015-09-23 | Toyota Motor Co Ltd | Solid electrolyte single crystal having perovskite structure and method for producing same |
| AT524311A4 (en) * | 2020-12-29 | 2022-05-15 | Fametec Gmbh | Apparatus for growing an artificially produced sapphire crystal |
-
1993
- 1993-06-25 JP JP05154880A patent/JP3115156B2/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2891731A4 (en) * | 2012-08-29 | 2015-09-23 | Toyota Motor Co Ltd | Solid electrolyte single crystal having perovskite structure and method for producing same |
| JP2016117644A (en) * | 2012-08-29 | 2016-06-30 | トヨタ自動車株式会社 | Solid electrolyte single crystal having perovskite structure and method for manufacturing the same |
| AT524311A4 (en) * | 2020-12-29 | 2022-05-15 | Fametec Gmbh | Apparatus for growing an artificially produced sapphire crystal |
| AT524311B1 (en) * | 2020-12-29 | 2022-05-15 | Fametec Gmbh | Apparatus for growing an artificially produced sapphire crystal |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3115156B2 (en) | 2000-12-04 |
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