Semiconductor device and manufacturing method thereof

摘要

The object of the present invention is to develop a manufacturing process for fabricating thin film transistors by using a crystalline semiconductor film appropriately for the purpose, in which the crystalline semiconductor film is formed by using a catalyst which enables crystallization at a low temperature and is easily gettered.Low temperature crystallization is realized by introducing Cu, a catalyst, on the amorphous semiconductor film and performing a heat treatment. Cu is gettered by immersing the polycrystalline semiconductor film which slightly includes Cu into a chemical fluid selected from a group consisting of a chemical including oxygen namely sulfuric acid. nitric acid, oxalic acid and nitrohydrochloric acid, and a chemical not including oxygen namely hydrochrolic acid and hydrofluoric acid