Method of Crystallizing Amorphous Silicon Films by Microwave Irradiation

摘要

A method is developed to crystallize amorphous silicon (a-Si) thin films, in cold environment, by combining microwave-absorbing materials (MAM) and microwave irradiation. The MAM is set on top or around of the a-Si thin film. MAM composes of dielectric, magnetic, semiconductor, ferroelectric and carbonaceous material oxides, carbides, nitrides and borides, which will absorb and concentrate electric or magnetic field of the microwave. The microwave frequency is selected from 1 to 50 GHz, at a power density not less than 5 W/cm². Temperature rise of the MAM is monitored and controlled by an optical pyrometer to be less than 600° C., and better be within 400-500° C. The application of MAM at patterned local areas leads to localized heating and crystallization of a-Si film right at the patterns to facilitate manufacture of semiconductor devices.