Sumitomo Metal Industries, Inc.

Toshiyuki Fujiwara

Hideki Fujiwara

Takayuki Kubo

Sumio Kobayashi

Shunji Miyahara

Shuichi Inami

Masahiko Okui

A single crystal material is filled in a crucible, and the whole of the single crystal material is melted to contain doping impurities. A solid layer coagulated upward from the bottom of the crucible is rendered to coexist with a melted layer over the solid layer. The solid layer is melted from the upper side thereof while pulling the single crystal from the melted layer. The ratio by weight between the solid layer and the single crystal material at the start of pulling is adjusted, together with the ratio by weight between the grown single crystal and the melting solid layer. The single crystal is thus grown while changing the volume of the melted layer.

Method of growing crystal

An apparatus for growing a single crystal having a crucible, two heaters arranged at the outside of the crucible and along the vertical direction, a heat shield placed at the outside of the heaters, a radiation shield for shielding the single crystal from the radiation heat, and an upper heat shield for preventing the upward heat, transfer of the heaters. In the apparatus, a melted layer and solid layer of raw material are formed in the upper and lower portions of the crucible, respectively. While melting the solid layer, the single crystal is pulled up. The lower portion of the heat shield is thinner than the upper portion. The ratio of the height to the diameter of the crucible is 0.85 or more. The melting amount of the solid layer is controlled in the pulling process according to the non-segregation condition in the variable-thickness melted layer method. The oxygen concentration of the pulled single crystal is controlled in the pulling process by adjusting the rotation speed and rotation direction of the crucible.

Apparatus and method of growing single crystal

Growing community of inventors

Nishinomiya, Japan

Toshiyuki Fujiwara