IMPROVEMENT OF THE QUALITY OF A-SIGE-H FILMS

The ADHT (alternately repeating deposition and hydrogen plasma treatme nt) method and the DLE (deposition of low emission) method were develo ped for the formation of high quality a-SiGe:H (hydrogenated amorphous silicon germanium) films. High photosensitivity was obtained by the A DHT and DLE methods, with a wide range of optical bandgaps between 1.3 eV and 1.7 eV, higher than those of films obtained by the hydrogen di lution method. It was also proved that these films were solar cell dev ice-grade. A conversion efficiency of 8.9% was obtained with a bandgap of 1.6 eV by the ADHT method, and a conversion efficiency of 8.2% and a short circuit current of 20.4 mA/cm(2) were obtained with a bandgap of 1.47 eV by the DLE method.