SEMICONDUCTOR ELEMENT, MANUFACTURING METHOD THEREOF THIN FILM TRANSISTOR, AND LASER ANNEALING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a method for crystallizing a semiconductor thin film by using a semiconductor laser such as a green laser. SOLUTION: A base layer and semiconductor layers are sequentially formed on a substrate for not less than two layers. Thus, laser energy irradiated on the upper semiconductor layer is given not only to the upper semiconductor layer but also to the lower semiconductor layer. Thus, the semiconductor thin film of a multilayer structure is obtained at a time. Since the lower layer operates as a heat bath by heat generated by absorption of laser energy transmitted through an upper polycrystalline Si film by the lower non-crystalline Si film, gentle annealing effect is given to the upper polycrystalline Si film. Thus, a crystallized thin film of high quality is obtained and necessary laser energy can be reduced. The thin film of high quality is realized by green laser advantageous in terms of maintenance, cost and capacitance. COPYRIGHT: (C)2008,JPO&INPIT