Abstract

A method of producing a reduced-defect density crystalline silicon film includes forming a first intrinsic silicon film on a substrate, forming a doped film including silicon or germanium on the first intrinsic silicon film, forming a second intrinsic silicon film on the doped film, and annealing to crystallize the doped film, the second intrinsic silicon film, and the first intrinsic silicon, wherein each film is amorphous at formation, wherein crystallization initiates within the doped film. A method of forming a thin film transistor includes forming an active layer in the crystallized second intrinsic silicon layer by doping the crystallized second intrinsic silicon layer in selected areas to form source and drain regions separated by a channel portion, forming a gate insulator layer on the crystallized second intrinsic silicon layer, and forming a gate electrode pattern over the gate insulator layer.