Preparation, Structure, and Applications of Thin Films of Silicon Monoxide and Titanium Dioxide

A material satisfying the chemical formula for silicon monoxide can be prepared by heating finely divided silicon and silica in vacuum. Silicon monoxide is structurally different from either silicon or silica and exists only in amorphous form. Vacuum-deposited thin films of silicon monoxide decompose to silicon and silica when heat-treated in an enert atmosphere and oxidize to silica when heated in air. Their oxidation rates in air at various temperatures have been measured by optical means. Silicon monoxide is especially suitable for depositing protective layers on first-surface mirrors and for preparing replica and support films for electron microscope and electron diffraction studies. Titanium dioxide films prepared by evaporating titanium and oxidizing it in air at 400° to 500°C. have a rutile structure. Such rutile films can be used for splitting beams and for increasing the reflectivity of first-surface mirrors.