p on n ion-implanted junctions in liquid phase epitaxy HgCdTe layers on CdTe substrates

Abstract
The first demonstrated achievement of p on n‐type activated junctions in HgCdTe material by arsenic ion implantation is reported. The junctions were formed by treating the implant as a finite diffusion source in the post‐implant anneals. The materials employed for this study were n‐type indium impurity‐doped liquid phase epitaxy HgCdTe grown on CdTe. Arsenic was selected as the candidate acceptor impurity since it activated during post‐implanted anneals in Hg vapor. The arsenic concentration profile determined by secondary ion mass spectroscopy showed that during post‐implant anneal a complex diffusion mechanism redistributes the arsenic. The activation efficiency appears to be mechanism dependent. In the junction region the implant activation efficiency is about 50%. Junction depth can be controlled by varying arsenic diffusion and background carrier concentration. Junction depths determined by the electron beam induced current technique were consistent with the differential Hall electrical profiles. A p on n junction is shown with excellent rectification characteristics and high breakdown voltage (sharp at 2.5 V and 77 °C). This was obtained from a liquid phase epitaxy Hg1−xCdxTe, with a compositional factor of x=0.23.