A method for polysilicon crystallization by simultaneous laser and rapid thermal annealing is disclosed. In the method, a substrate that has an amorphous silicon layer on top is first provided and positioned on a conveyor situated inside a temperature-controlled chamber. The temperature-controlled chamber is equipped with a window in a top wall that is substantially transparent to thermal and laser energy. A beam of thermal energy and simultaneously a beam of laser energy merged with the thermal energy is then directed through the window onto a top surface of the substrate to convert an amorphous silicon film into a polysilicon film.