Method for manufacturing semiconductor device, and laser irradiation apparatus

摘要

It is an object of the present invention to provide a method for manufacturing a crystalline semiconductor film comprising the steps of crystallizing with the use of the metal element for promoting the crystallization to control the orientation and irradiating the laser once to form a crystalline semiconductor film having a small crystal grain arranged in a grid pattern at a regular interval. In the present invention made in view of the above object, a ridge forms a grid pattern on a surface of the crystalline semiconductor film in such a way that a crystalline semiconductor film is formed by adding the metal element for promoting the crystallization to the amorphous semiconductor film and the pulsed laser whose polarization direction is controlled is irradiated thereto. As the means for controlling the polarization direction, a half-wave plate or a mirror is used.