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AssigneeSumitomo Metal Industries, Ltd.
InventorsKazuhiko Kusunoki, Kazuhito Kamei, Nobuyoshi Yashiro, Akihiro Yauchi, Yoshihisa Ueda, Yutaka Itoh, Nobuhiro Okada
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A SiC single crystal is produced by the solution growth method in which a seed crystal attached to a seed shaft is immersed in a solution of SiC dissolved in a melt of Si or a Si alloy and a SiC single crystal is allowed to grow on the seed crystal by gradually cooling the solution or by providing a temperature gradient therein. To this method, accelerated rotation of a crucible is applied by repeatedly accelerating to a prescribed rotational speed and holding at that speed and decelerating to a lower rotational speed or a 0 rotational speed. The rotational direction of the crucible may be reversed each acceleration. The seed shaft may also be rotated synchronously with the rotation of the crucible in the same or opposite rotational as the crucible. A large, good quality single crystal having no inclusions are produced with a high crystal growth rate.
A method for producing a silicon carbide single crystal comprising immersing a seed crystal on which SiC is to be grown by the solution growth method and which is attached to a seed shaft in a melt in a rotating crucible, the melt comprises Si and C and at least one metal element M and containing silicon carbide (SiC) dissolved therein, and allowing a SiC single crystal to grow on the seed crystal by creating a supersaturated SiC concentration in the melt at least in the periphery of the seed crystal, characterized in that the melt is stirred by periodically changing the rotational speed or the rotational speed and the rotational direction of the crystal,
A method for producing a silicon carbide single crystal comprising immersing a seed crystal on which SiC is to be grown by the solution growth method and which is attached to a seed shaft in a melt in a rotating crucible, the melt comprising (1) Si and C or (2) Si and C and at least one metal element M and containing silicon carbide (SiC) dissolved therein, and allowing a SiC single crystal to grow on the seed crystal by creating a supersaturated SiC concentration in the melt at least in the periphery of the seed crystal, characterized in that the melt is stirred by periodically changing the rotational speed or the rotational speed and the rotational direction of the crystal,
Dependencies are inferred from the claim text.