SEMICONDUCTOR DEVICE AND MANUFACTURE THEREOF

摘要

PROBLEM TO BE SOLVED: To provide a constitution for forming a polysilicon film having uniform crystallinity. SOLUTION: A bottom gate type TFT structure has a thermal relaxation layer 104 to cover a gate electrode 103, this layer 104 having a thermal conductivity lower than that of the gate electrode for suppressing thermal propagation to the gate electrode 103. This prevents local temp. gradient from occurring due to the heat-absorbing action of the gate electrode when an amorphous Si film is crystallized by a laser, thus obtaining a polysilicon film having superior crystallinity which is very uniform.