The effects of low‐power irradiation of an n‐type GaAs surface by a 193‐nm excimer laser during tungsten metallization have been examined. Schottky diode characteristics of surfaces held under ultrahigh vacuum (10−9 Torr) conditions and in oxygen and chlorine ambients of 10−6 Torr show significant shifts in effective barrier height due to irradiation and depending on the ambient. The results of the electrical measurements are interpreted in terms of the possible laser surface chemistry. The applications for in situ surface cleaning for device processing within a vacuum GaAs growth chamber and applications for laser photochemical etching and oxidation of GaAs are discussed.
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© 1987 American Institute of Physics.
1987
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