J. Nakata et al., HIGH-FIELD ELECTRON-TRANSPORT AND HOT-ELECTRON PHENOMENA IN HYDROGENATED AMORPHOUS-SILICON FILMS, JPN J A P 1, 33(10), 1994, pp. 5640-5646
Electron transport under high electric held in hydrogenated amorphous
silicon (a-Si:H) films has been investigated by means of time-of-light
(TOF) measurements. The drift mobility mu increased with increasing a
pplied electric field E accompanied by a simultaneous increase in the
dispersion parameter alpha resulting in nondispersive transport. The e
lectron thermal runaway breakdown held E with optical carrier injecti
on decreased with increasing ambient temperature T-a in accordance wit
h the hot electron theory in amorphous solids [H. Frohlich: Proc, R. S
ec. London A 118 (1947) 521]. The held dependencies of mu and alpha ar
e also explained by taking account of the increase in the effective el
ectron temperature (hot electron phenomenon) at high field in the theo
ry of dispersive transport.