Planar-doped structures by atomic layer epitaxy

Abstract

Atomic layer epitaxy (ALE) has been used for the low temperature deposition of planar-doped structures using organometallic sources, AsH3 and H2Se. Carrier concentrations in the 1019/cm3 range have been achieved, with a sharp concentration profile comparable to that reported for equivalent structures by molecular beam epitaxy (MBE). A set of planar-doped Se sheets, separated by 50 A of undoped GaAs, was used for nonalloyed contacting layers to n-GaAs films with contact resistivity in the low 10-6?cm2 range. The sidewall regrowth capability of ALE was also used in reducing the parasitic source and drain resistances by about 30%. Finally, a planar doped field effect transistor (FET) were fabricated. The performance of these ALE devices were comparable to FET devices fabricated by other growth techniques.