US Patent 7115452 Method of making semiconductor device

To provide a method of removing a catalyst element from a crystalline silicon film obtained by solid phase growth using the catalyst element promoting crystallization, phosphorus is implanted selectively to the crystalline silicon film having the catalyst element whereby a portion of the silicon film implanted with phosphorus is made amorphous, and when a thermal annealing treatment is performed and the silicon film is heated, the catalyst element is moved to an amorphous portion implanted with phosphorus having large getting capacity by which the concentration of the catalyst element in the silicon film is lowered and a semiconductor device is fabricated by using the silicon film.