New semiconductor technologies for 300 mm wafer processing have been developed to meet the requirements for the next generation device fabrication. One of the strong candidates for supporting 300 mm semiconductor manufacturing is enlarged microwave plasma deposition technology. The polysilicon films deposited with enlarged microwave plasma technology were studied in this work. The deposited polysilicon films with the enlarged microwave plasma technology showed a variety of crystallinity as well as epitaxy on silicon substrates even at 430 degrees C substrate temperature. This low temperature deposition is very promising for application to the 300 mm semiconductor manufacture since the more crystallinity guarantees the better device performance. It was shown that the slower deposition rates promoted the higher crystallinity. It was also observed that the crystallographic orientations of the polysilicon grains changed gradually during deposition, and this was modeled and explained. It was therefore concluded that the enlarged microwave plasma deposition technology will be an important part of the future technologies for the giga dynamic random access memory era.