Method and an apparatus for fabricating a semiconductor device

A method for fabricating a semiconductor device, comprising the steps of:

• depositing an amorphous semiconductor film on a substrate having an insulating surface;
• and
• polycrystallizing the amorphous semiconductor film to obtain a polycrstallized semiconductor,
• wherein the step of polycrystallizing the amorphous semiconductor film includes the steps of:
• heating an under-heating portion on the substrate with the amorphous semiconductor film formed thereon with a heating source;
• setting a shifting speed in such a range that a temperature of the under-heating portion becomes equal to or higher than a melting temperature of the amorphous semiconductor but lower than a melting temperature of the polycrystallized semiconductor, by setting the shifting speed to be equal to or less than a value obtained by dividing a width of the under-heating portion by a time required from the start of the heating until the temperature of the under-heating portion reaches the melting temperature of the amorphous semiconductor;
• and
• shifting at least one of the heating source and the substrate at the shifting speed so as to shift the under-heating portion along the substrate surface,
• wherein during the heating step, the amorphous semiconductor and the already-polycrystallized semiconductor are located adjacent each other within the under-heating portion so as to be simultaneously heated, and polycrystallization proceeds from an edge of the already-polycrystallized semiconductor.