Thin film semiconductor and method for manufacturing the same, semiconductor device and method for manufacturing the same

摘要

The present invention is related to a thin film semiconductor which can be regarded as substantially a single crystal and a semiconductor device comprising an active layer formed by the thin film semiconductor. At least a concave or convex pattern is formed intentionally on a insulating film provided in contact with the lower surface of an amorphous silicon film, whereby at least a site is formed in which a metal element for accelerating crystallization can be segregated. Therefore, a crystal nuclei is selectively formed in a portion where the concave or convex pattern is located, which carries out controlling a crystal diameter. Thus, a crystalline silicon film is obtained. A crystallinity of the crystalline silicon film is improved by the irradiation of a laser light or an intense light having an energy equivalent to that of the laser light, whereby a monodomain region in which no grain boundary substantially exit is formed.