Process for manufacturing a semiconductor device

摘要

A first amorphous semiconductor film is formed on an insulating surface. A catalyst element for promoting crystallization is added thereto. Thereafter, by a first heat treatment in an inert gas, a first crystalline semiconductor film is formed. A barrier layer and a second semiconductor layer are formed on the first crystalline semiconductor film. The second semiconductor layer contains a rare gas element at a concentration of 1x10¹⁹ to 2x10²²/cm³, preferably 1x10²⁰ to 1x10²¹/cm³ and oxygen at a concentration of 5x10¹⁷ to 1x10²¹/cm³. Subsequently, by a second treatment in an inert gas, the catalyst element remaining in the first crystalline semiconductor film is moved to the second semiconductor film.