Photoconductivity gain over 10 at a large electric field in wide gap a-Si:H

Abstract

Wide band gap amorphous silicon films and p–i–n diodes were prepared by a chemical annealing method. Films had dark conductivities consistent with the large band gaps, low impurity levels, intrinsic conduction, and corresponding low thermal generation rates. Primary photo current measurements of these films was consistent with an electron μτ of 10−8 cm2/V. To provide blocking at large electric fields, p and n-layers were optimized . Since it is known that at electric fields greater than 106 V/cm other amorphous materials such as a-Se exhibit avalanche multiplication, the wide band gap amorphous silicon p–i–n diodes were used to probe the prospect of avalanche multiplication in the amorphous silicon system.