Laser processing method of semiconductor device

摘要

It is intended to provide a technique of separately forming thin-film transistors disposed in a peripheral circuit area and those disposed in a pixel area in accordance with characteristics required therefor in a manufacturing process of semiconductor devices to constitute a liquid crystal display device. In an annealing step by laser light illumination, laser light is selectively applied to a semiconductor thin-film by partially masking it. For example, to illuminate the peripheral circuit area and the pixel area with laser light under different conditions in manufacture of an active matrix liquid crystal display device, laser light is applied at necessary illumination energy densities by using a mask. In this manner, a crystalline silicon film having a necessary degree of crystallinity in a selective manner can be obtained.