We report selected area growth of GaAs by XeF excimer laser induced pyrolysis of triethylgallium (TEGa) adsorbed on GaAs(100). TEGa dissociatively chemisorbs at 400thinsp;deg;C to form a stable layer which decomposes further under laser irradiation to liberate hydrocarbon products. The Ga left behind on the surface reacts with As2and As4(formed by pyrolysis of trimethylarsine or triethylarsine in a side tube) to grow GaAs in irradiated areas. Patterned films with feature sizes of sim;70 mgr;m (limited by the projection system) were grown by this method. Interference between the incident beam and light scattered along the surface causes a substructure of parallel lines, with a spacing about equal to the laser wavelength (0.35 mgr;m), to form on the features. This indicates that the ultimate spatial resolution is comparable to that predicted by thermal diffusion calculations (sim;0.3 mgr;m).
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