Replacement of magnesium in InGaAs/InP heterostructures during zinc diffusion

Abstract

Zn diffusions from spin-on films have been carried out into n-InP/p+-InGaAs/n-InP heterostructures, which were grown by metalorganic vapor phase epitaxy for heterojunction bipolar transistors with Mg as a p dopant. After diffusion, Mg was completely substituted by Zn and enriched in the spin-on film. In the presence of Mg, the indiffusion of Zn is strongly enhanced. By varying doping levels and diffusion conditions, the underlying mechanism is studied and compared to recent experiments with Be-doped AlGaAs/GaAs heterostructures.