Ion beam deposition of zinc sulphide films

Preliminary experiments designed to investigate the properties of ion beam deposited zinc sulphide films are reported. The films were deposited onto glass and germanium substrates and studied utilising Rutherford backscattering of 1.5 MeV helium ions and optical absorption measurements. The beam used was obtained from a conventional duoplasmatron ion source fitted with a molybdenum expansion cup. The optical properties of one film produced in this way were found to be similar to those expected for a good quality zinc sulphide film prepared by conventional techniques. It was confirmed that films with the correct stoichiometry can be obtained using this method. Although abrasion tests indicated that the ion beam deposited films were no better than those obtained using conventional evaporation in conjunction with sputter cleaning, it is considered that the preliminary experiments have established the feasibility of ion beam deposition of a binary compound. (U.K.)