Demonstration of an isolated buried channel field-effect transistor fabricated via in situ patterned electron-beam deposition of Si in GaAs

A partial monolayer of silane, SiH₄, adsorbed on a GaAs(100) surface at 40 K may be fixed in a desired pattern by irradiation with an electron microbeam, and then covered in situ by GaAs grown by molecular-beam epitaxy. The initial rate of Si coverage under irradiation by 1.5 keV electrons is (0.031±0.005) Si per electron per monolayer of silane. Applications include the in situ fabrication via patterned doping of circuit elements and structures with interesting electronic properties. As an example, we have made an isolated buried channel field-effect transistor and measured its properties.