Double zinc diffusion fronts in InP—Theory and experiment

Abstract
Diffusion of Zn or Cd in n‐type III‐V material has been extensively used for forming pn junctions in lasers and detectors. However, if the substrate material used for diffusion has an electron concentration less than 5×1016 cm3, two separate diffusion fronts will appear which alter completely the electrical property of the junction. We have investigated this phenomenon by electron beam induced current (EBIC) and secondary ion mass spectroscopy (SIMS). A theory is proposed, for the first time, in good agreement with experiment.