A method for planarizing polysilicon comprises providing a substrate, forming a dielectric layer on the substrate, forming an amorphous silicon film on the dielectric layer, etching the amorphous silicon film to remove native oxide formed on a surface of the amorphous silicon film, exposing the surface of the amorphous silicon film to a first radiation source to polycrystallize the amorphous silicon film into a polysilicon film, etching the polysilicon film to remove weak bonded silicon formed on a surface of the polysilicon film, and exposing the surface of the polysilicon film to a second radiation source to reflow the polysilicon film.