SILICON CARBIDE CRYSTAL GROWTH METHOD

• Main Authors: YAMAGATA NORIO, HAMAGUCHI MASARU, SHINTANI HISAFUMI, MINOWA TAKEHISA
• Format: Patent
• Language: English; Japanese
• Published: 18.06.2015
• Subjects: AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUSPOLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR; CHEMISTRY; CRYSTAL GROWTH; METALLURGY; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; REFINING BY ZONE-MELTING OF MATERIAL; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; SINGLE-CRYSTAL-GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL ORUNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL

PROBLEM TO BE SOLVED: To provide high quality single crystal silicon carbide with less defects.SOLUTION: In a silicon carbide crystal growth method using a solution technique, a melting pot based on SiC is used as a storage section of Si-C solution. When the melting pot is heated, temperature distribution is generated in a manner that increases a temperature with an increasing depth of the Si-C solution from an upper side to a lower side thereof in the melting pot. Also, Si and C originated from the melting pot based on the SiC is eluted from a high temperature region on the surface of the melting pot where the same contacts the Si-C solution and thereby preventing polycrystalline SiC from generating on the surface of the melting pot where the same contacts the Si-C solution. With the silicon carbide solution kept in this state, the same is brought into contact with SiC seed crystals at an upper section thereof so as to allow single SiC crystals to be generated on the SiC seed crystals. By using the melting pot based on the SiC, the method curbs: a composition variation in the Si-C solution; precipitation of the polycrystalline SiC on an inner wall of the melting pot; and generation of metallic carbide formed when added metallic elements M combine with carbon C. 【課題】低欠陥で高品質な単結晶炭化珪素を提供すること。【解決手段】溶液法による炭化珪素の結晶成長方法において、Ｓｉ−Ｃ溶液の収容部としてＳｉＣを主成分とする坩堝を用いる。このＳｉＣ坩堝を加熱して、坩堝内のＳｉ−Ｃ溶液の温度が上側から下側に向かって高くなる温度分布を形成するとともに、Ｓｉ−Ｃ溶液と接触する坩堝表面の高温領域から該坩堝の主成分であるＳｉＣを源とするＳｉおよびＣを前記Ｓｉ−Ｃ溶液内に溶出せしめ、Ｓｉ−Ｃ溶液と接触する坩堝表面でのＳｉＣ多結晶の析出を抑制する。このような状態のＳｉ−Ｃ溶液に、坩堝の上部からＳｉＣ種結晶を接触させて、該ＳｉＣ種結晶上にＳｉＣ単結晶を成長させる。ＳｉＣを主成分とする坩堝を用いることにより、Ｓ−Ｃ溶液の組成変動が少なく、坩堝の内壁に析出する多結晶や添加金属元素Ｍと炭素Ｃが結合して形成される金属炭化物の発生も抑制される。【選択図】図１