Solid phase crystallization of amorphous silicon films for poly-Si thin-film transistors (TFT's) has advantages of low cost and excellent uniformity, but the crystallization temperature is too high, Using a microwave annealing method, we lowered the crystallization temperature and shortened the crystallization time. The complete crystallization time at 550 degrees C was within 2 h. The device parameters of TFT's with the poly-Si films crystallized by microwave annealing were similar to those of TFT's with the poly-Si films crystallized by conventional furnace annealing. The new crystallization method seems attractive because of low crystallization temperature, short crystallization time, and comparable film properties.