Method for in-situ polycrystalline thin film growth

A method for in-situ polycrystalline thin film growth is provided. A catalyst enhanced chemical vapor deposition (CECVD) apparatus is used to grow the polycrystalline silicon thin film. No subsequent annealing or dehydrogenating process is needed. The method comprises exhausting a chamber to form a vacuum chamber, and then purging vacuum chamber and introducing a catalyst. A substrate is then placed in the vacuum chamber and reaction gas is injected into the chamber. The reaction gas reacts with the catalyst in the chamber to grow a polycrystalline thin film on the substrate. The inventive method reduces processing time and production cost and can be used to fabricate larger devices due to the elimination of bulky annealing equipment.