Photodoping sensitivity of Ag into amorphous As2S3 films

Abstract

The photodoping of Ag into as-evaporated, annealed, and pre-exposed As2S3 films has been studied by measuring the resistance and the optical density of Ag films and the depth of Ag doping estimated by the refractive index change. The photodoping consists of a dissolution process and a diffusion process. In the dissolution process, the spectral sensitivity reflects the absorption spectra of As2S3 films and the sensitivity limit is at about 650 nm. The dissolution rate of Ag into As2S3 is largest in the pre-exposed films and is smallest in the as-evaporated films. In the diffusion process, the spectral sensitivity limit is at about 700 nm and the diffusion rate varies only slightly over the three sets of As2S3 film conditions.