SEMICONDUCTOR DEVICE AND ITS FABRICATION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a method for improving the reliability and yield of a thin film transistor by controlling crystallinity. SOLUTION: Two gate electrodes are formed on an island like amorphous silicon film. Impurities are implanted using the electrodes as masks. A coat containing at least one of nickel, iron, copper or platinum is formed adhered to a portion in the impurity region. The crystallization develops and the impurity region and a channel forming region are crystallized by annealing at a temperature lower than the crystallization temperature of pure amorphous silicon.