Ultrahigh vacuum surface analysis coupled with a high pressure system for the study of near critical and supercritical fluid processing

A system has been constructed for ultrahigh vacuum analysis investigation of surfaces after high pressure fluid processing. The system features a cell capable of withstanding pressures up to 400 bar that opens directly into an ultrahigh vacuum (10−10 Torr) system to allow transfer of samples for analysis. Temperature control of the cell and fluid is possible to within ±1 °C up to temperatures of 400 °C. The high pressure system design allows the preparation and study of supercritical fluid mixtures as well as of pure components. X-ray photoelectron spectroscopy, Auger electron spectroscopy, sputter etching, and vacuum anneal capabilities comprise the surface analysis system. The fluids investigated include supercritical carbon dioxide, methanol, water, and their mixtures; these are applied to processes such as surface cleaning and thin film etching using high pressure fluids.