Nano-phase separation of arsenic tri-sulphide (As2S3) film and its effect on plasma etching

We present evidence of nano-scale phase separation in amorphous arsenic tri-sulphide films prepared by ultra-fast pulsed laser deposition based on Raman spectroscopy, X-ray photo-electron spectroscopy, and atomic force microscopy. We also show the results from plasma etching this material and conclude that the grainy structure of etched surfaces comes from the differential chemical etch rates of the different phases.