PURPOSE: To obtain a high-quality and homogeneous single crystal semiconductor thin film, by forming single crystal semiconductor sections serving as seed sections on an insulation layer so as to be contacted with a non-single-crystal semiconductor thin film, so that the single crystal semiconductor on the insulation layer is heated to a temperature similar to that of the non-single-crystal semiconductor when irradiated with energy beams and the semiconductor is recrystallized smoothly after the irradiation.

CONSTITUTION: SiO2 insulation layers 13 are formed on one principal surface of a single crystal silicon substrate 11 except its regions where seed sections 15 are to be provided. A polycrystalline silicon thin film 12 as a non-single-crystal thin film is formed on the SiO2 layers 13 while it is separated by side walls 21 of the SiO2 layers 13 into island regions. An LOCOS-type wafer 14 thus constructed is irradiated with electronic beams. Since extended regions 15 of the seed sections 15 and the polycrystalline silicon thin film 12 are located on the same SiO2 layer 13, they have the same heat conductivity in their underlying layers and, hence, they are heated to an approximately equal temperature. Accordingly, single crystal silicon in the extended regions 16 of the seed sections 15 can be melted as easily as the polycrystalline silicon thin film 12 and can be utilized effectively as seeds for recrystallization after irradiation of electronic beams.