Patent ID: 7268026

Claim:
A method for manufacturing a semiconductor device, comprising the steps of: forming a crystalline silicon film on a substrate, the crystalline silicon film having a thickness, wherein the formation of the crystalline silicon film is by deposition including the steps of: i) forming a hole in the substrate such that the hole extends approximately perpendicular to the length at a predetermined position; ii) forming an amorphous silicon film on the substrate such that the hole is filled with the amorphous silicon film; and iii) turning a region of the amorphous silicon film about the hole into a crystalline silicon film in a single-crystalline state or a polycrystalline state or any mixture of both states by irradiating the region with a laser beam and, while maintaining the amorphous silicon film at a bottom part of the hole in a non-melting state and bringing a remainder of the amorphous silicon film into a melting state to thereby generate crystal growth using the amorphous silicon maintained in the non-melting state as a crystalline nucleus as the amorphous silicon film cools; providing the crystalline silicon film with a source region, a channel region and a drain region, wherein a distance from the source region to the drain region defines an approximate length of the semiconductor device; forming a plurality of fin-shaped channel portions extending parallel to the length and between the source region and the drain region, wherein the source region, the drain region, and the channel portions are formed in a single single-crystalline grain of the crystalline silicon film; forming a gate insulation film on a surface portion of each channel portion; and forming a transistor by forming a gate electrode by covering part of the gate insulation film of each channel portion.