Abrupt p- type doping transitions using bis-(cyclopentadienyl)-magnesium in metal-organic vapor phase epitaxy of GaAs
Extremely abrupt p+-n doping transitions have been realized in GaAs and AlGaAs grown by metal-organic vapor phase epitaxy using bis-(cyclopentadienyl)-magnesium (Cp2Mg) as precursor for the Mg p-dopant. The Mg incorporation was found to depend linearly on the Cp2Mg concentration, in contrast to reports of a supralinear behaviour. Methods for eliminating reactor memory effects are described. Layers doped to about 1 x 1019 cm-3 and as thin as 100 nm at 10% of the peak doping have been grown under conditions compatible with growth of high quality Al0.3Ga0.7As. Atomic and carrier profiles of ap-plications for heterostructure bipolar transistor structures are presented.