Low Temperature Pulsed Plasma Deposition. Part 2. The Production of Novel Amorphous Compounds of Germanium in Thin Film

Recently, a new process for the room temperature, low pressure, deposition of thin films has been published, which uses pulsed radio-frequency discharges of very high power levels. Here we describe the use of the process for the deposition of amorphous compounds containing germanium, sulphur, and phosphorus. The deposited compounds, many for which cannot be readily deposited using any other method, are shown to have useful properties as infra-red coatings and as compound semiconductors with band gaps extending into the visible spectrum. The stability of the deposited compounds on exposure to high temperatures and on exposure to moisture is found to correlate with deposition conditions and compound stoichiometry, and the use of these materials under adverse environmental conditions is discussed.