| 摘要 |
PROBLEM TO BE SOLVED: To produce compd. semiconductor single crystals, such as GaAs and InP, at a high yield by a VGF process or VB process while preventing the generating of twins in a crystal diameter increasing section. SOLUTION: Such a crucible 1 which has a seed crystal installation section 1a at the center in its bottom and is inclined in its base 1b at a prescribed angleαof >=80 deg. to <90 deg. in a perpendicular direction so as to make the base lower gradually toward its center is used. The temp. gradient in the diameter increasing section is specified to <5 deg.C/cm and the crystal growth rate dZ/dT [cm/s] in the diameter increasing section is specified to >=70% of the calculated value of dZ/dt=(K/Hf.ρ)dT/dZ and <=20 times the same. Hf is the latent heat [J/g].dT/dZ of a raw material melt, dt/dZ is a temp. gradient [ deg.C/cm], K is thermal conductivity [J/cm.s.K] andρis the sp. gr. [g/cm<3> ] of the crystal.
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