999Nov 12, 2002Semiconductor Energy Laboratory Co., Ltd.Semiconductor device and its manufacturing methodUS6504174Mar 28, 2000Jan 7, 2003Semiconductor Energy Laboratory Co., Ltd.Thin film transistor; crystal silicon thin film formed on a substrate such as a glass and quartz; containing a metal element which promotes crystallization of siliconUS6528358Mar 28, 2000Mar 4, 2003Semiconductor Energy Lab