Ion‐Implanted Gallium‐Arsenide‐Phosphide Surfaces

Abstract

Study of thermal degradation of mechanical surface perfection and surface photoluminescence (PL) of samples, some of which received high dose room temperature Zn+ or Ar+ ion implants and others of which were unimplanted, strongly suggests that PL degradation and thermal etch pit formation have a common origin. Thermal etch pits are believed to nucleate at dislocations reaching the surface and these same dislocations act as sources of vacancy injection into the bulk, resulting in PL degradation. Ion implants rendering the surface amorphous are found to retard formation of thermal etch pits and to retard PL degradation during high temperature anneals. The model presented may explain the unusual dish‐shaped p‐n junction profiles observed when Zn+ is implanted into n‐type at room temperature and annealed.