US Patent 7256102 Manufacturing method of thin film device substrate

An object of the present invention is to prevent the thin film device formed by laser annealing from making, due to overheat, abnormal operations. Firstly, on a glass substrate 101. a heat insulating film, a silicon oxide film and an amorphous silicon film are formed in succession, and the amorphous silicon film is irradiated from above with a laser beam of an excimer laser. After being molten, the amorphous silicon film undergoes recrystallization to form a polycrystalline silicon film. Subsequently, using the polycrystalline silicon film as an active layer, a TFT is formed, and then a plastic substrate is bonded onto the TFT, and finally the glass substrate is peeled off by way of the heat insulating film, whereby a transfer of the TFT is completed. Because the heat insulating film is removed, abnormality caused by overheat at the time of operation is well prevented from occurring.