PURPOSE: To rapidly start epitaxial growth by stirring and homogenizing raw material melt by a floating plate.

CONSTITUTION: A growth tank 4 is arranged under a melt sink 3 in which raw material melt 2 is housed and plural substrate wafers 1 are housed in the growth tank 4. The growth tank 4 is integrally provided with a pressing rod 14 extended to the melt sink 3 and a floating plate 10 in which plural through holes 11 are formed is inserted into the pressing rod 14. Floating of the floating plate 10 is restricted by an engaging part of the pressing rod 14 and the floating plate 10 is released from restricted state and raised by relative movement of the growth tank 4. Thereby, the raw material melt 2 is homogenized by stirring flow due to raising of the floating plate 10 to prepare the raw material melt 2 in a short time.