Temperature dependence of the electron drift mobility (mu (d)) in a-Si:H, a
nd in a set of three a-SiNx:H alloys has been determined from the steady-st
ate photoconductivity and response time measurements. The activation energy
of the a-Si:H is found to be 0.11 eV and calculated drift mobility is simi
lar to0.1 cm(2) V-1 s(-1) at room temperature. While the activation energy
of the alloys increases up to 0.25 eV with increase of nitrogen content and
for the sample with the highest N content, the room temperature drift mobi
lty decreases to similar to2.4 x 10(-6) cm(2) V-1 s(-1). The results confir
m that the conduction band tail broadens with an increase of nitrogen conte
nt in a-SiNx:H. (C) 2001 Elsevier Science B.V. All rights reserved.