LOW-HYDROGEN-CONTENT, STABLE AMORPHOUS-SILICON THIN-FILMS PREPARED BYION-ASSISTED METHOD

Low-hydrogen (H)-content(less than or equal to 10%) amorphous silicon (a-Si) films have been prepared by the hydrogen ion- and atom-assisted ionized cluster-based deposition method. In this technique, hydrogen content can be controlled independently and the optical gap (E(opt3)) of 1.5 to 1.15 eV can be obtained within an acceptable range of substr ate temperature (180 to 230 degrees C). The variation of optoelectroni c properties with process parameters has been discussed. The stability against light exposure of these low-H-content films has been verified . The films are not susceptible to Light exposure; however, for higher H content, film properties degrade, albeit slightly. The degradation behavior has been compared with that of a hydrogenated amorphous silic on germanium (a-SiGe:H) film with the same E(opt3) (1.31 eV) and the s uperiority of low-H-content a-Si with regard to stability was indicate d.