LOW-TEMPERATURE DOPANT ACTIVATION AND ITS APPLICATION TO POLYCRYSTALLINE SILICON THIN-FILM TRANSISTORS

Low-temperature activation of dopants in amorphous silicon films was a chieved by a new method and high-performance polycrystalline silicon t hin film transistors were fabricated through its application. It was f ound that the dopants implanted into amorphous silicon were activated simultaneously with the crystallization of amorphous silicon. With the help of a thin nickel layer, the thermal budget for dopant activation and crystallization was considerably reduced, from 600 degrees C (30 h) to 500 degrees C (5 h). Even without plasma hydrogenation, the n-ch annel polycrystalline silicon thin film transistors fabricated at temp eratures below 500 degrees C showed a mobility of 120 cm(2)/V s, which is much higher than that of conventional devices fabricated at 600 de grees C. (C) 1996 American Institute of Physics.