BEAM HOMOGENIZER AND LASER IRRADIATOR, SEMICONDUCTOR DEVICE, AND METHOD OF MANUFACTURING THE SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To solve the problem of a linear laser beam, having uniform energy used in the annealing process of an amorphous semiconductor film where a long linear laser beam is required for mass production, a very expensive optical lens is required for forming a linear laser beam of 600 mm or longer by using the conventional transmission type optical system, and the length of 600 mm corresponds to the length of one side of a large substrate for mass production. SOLUTION: The problem is solved by using an optical system comprising reflectors shown in Fig. 1. When beam splitting reflectors 1106 and 1107 are used, a linear laser beam having uniform energy can be formed through an arrangement consisting only of reflectors. The reflector can be machined very easily, as compared with a transmission type lens and can be manufactured very inexpensively in case of a large scale optical system. When the optical system is employed, a linear laser beam of 600 mm or longer can be formed relatively easily.