MOBILITY-LIFETIME PRODUCT IN MICRODOPED AMORPHOUS-SILICON DEPOSITED BY HOT-WIPE CHEMICAL-VAPOR-DEPOSITION

The drift mobility deep trapping lifetime product, mu tau d, of electr ons, mu tau(e), and holes, mu tau(h), of hydrogenated amorphous silico n prepared using hot-wire chemical vapor deposition at substrate tempe rature of 200 degrees C was calculated using charge-collection as a fu nction of applied voltage curves from time-of-flight measurements. mu tau(d) was observed to be a function of the position of the Fermi leve l. Microdoping with trimethylboron was used to go from undoped (slight ly n-type, mu tau(e) > mu tau(h)) to slightly p-doped (mu tau(h) > mu tau(e)) films. (C) 1998 Elsevier Science B.V. All rights reserved.