Patent ID: 8884296

Claim:
A thin-film transistor device manufacturing method, comprising: providing a substrate; forming a plurality of gate electrodes above the substrate; forming a silicon nitride layer on the plurality of gate electrodes; forming a silicon oxide layer on the silicon nitride layer; forming an amorphous silicon layer on the silicon oxide layer; crystallizing the amorphous silicon layer using laser light emitted from a predetermined laser of 405 nm to 488 nm in wavelength while moving the predetermined laser in a given direction relative to the substrate, to produce a crystalline silicon layer; and forming a source electrode and a drain electrode on the crystalline silicon layer in a region that corresponds to each of the plurality of gate electrodes, wherein a film thickness of the silicon oxide layer, a film thickness of the silicon nitride layer, and a film thickness of the amorphous silicon layer satisfy X and Y that are in ranges defined by Expressions 1 to 6: Y≧ 0.264+14.444 ×ΔA′ Expression 1 X≦ 0.729−67.777×Δ A′ Expression 2 Y≦− 0.388 X+ 0.584−21.124 ×ΔA′ Expression 3 Y≦ 0.427−28.519 ×ΔA′ Expression 4 X≧ 0.344+32.963 ×ΔA′ Expression 5 Y≧− 0.388 X+ 0.457+21.412 ×ΔA′, Expression 6 where X is a value obtained by dividing an optical film thickness of the amorphous silicon layer by the wavelength of the laser light, the optical film thickness of the amorphous silicon layer being a result of multiplying the film thickness of the amorphous silicon layer by a refractive index of the amorphous silicon layer, Y is a value obtained by dividing a silicon oxide layer converted optical film thickness by the wavelength of the laser light, the silicon oxide layer converted optical film thickness being a value obtained by dividing a sum of an optical film thickness of the silicon oxide layer and an optical film thickness of the silicon nitride layer by a refractive index of the silicon oxide layer, the optical film thickness of the silicon oxide layer being a result of multiplying the film thickness of the silicon oxide layer by the refractive index of the silicon oxide layer, and the optical film thickness of the silicon nitride layer being a result of multiplying the film thickness of the silicon nitride layer by a refractive index of the silicon nitride layer, and ΔA′ is a value calculated according to an expression (A G /d G )×(ρ Si ×c Si )/(ρ G ×c G ), where ρ Si and c Si are respectively a density and a specific heat of the amorphous silicon layer, d G , ρ G , and c G are respectively a film thickness, a density, and a specific heat of the gate electrode, and A G is a maximum absorptance of the gate electrode when the amorphous silicon layer located above the gate electrode and the amorphous silicon layer not located above the gate electrode have an equal light absorptance for the laser light.