Patent ID: 7525135

Claim:
A semiconductor device, comprising: a transparent insulation substrate; a poly-silicon layer formed on said substrate; a laser-irradiated source region and a separate laser-irradiated drain region in an impurity-doped region in said poly-silicon layer; a channel region formed between said source region and said drain region in said poly-silicon layer; a first insulation layer which is formed on said poly-silicon layer and which is to serve as a gate insulation layer; a gate electrode having a plurality of stacked layers of mutually different materials, said gate electrode being formed on a portion of said first insulation layer that is above said channel region; and a second insulation layer which covers said gate electrode and said gate insulation layer, said second insulation layer having a surface with a step above said gate electrode, in which the surface of said second insulation layer is low above a periphery of said gate electrode but high in a center of said gate electrode, wherein said source region and said drain region are formed by irradiation of laser beam through said first insulation layer and said second insulation layer, the reflectance of said laser beam at a portion of said second insulation layer above the center of said gate electrode is higher than the reflectance of the laser beam at portions of a first multi-layer insulation film consisting of said first insulation layer and said second insulation layer above said source region and said drain region, and wherein the width of said step formed in the surface of said second insulation layer is equal to or narrower than ¼ of the width of said gate electrode.