Ion implantation in III–V compounds

Abstract

Because of their specific physical properties AIIIBV compound semiconductors are widely used for the fabrication of special electronic and optoelectronic devices. For a planar technology ion implantation seems to be the most promising doping method for these materials because the conventional diffusion technology is complicated due to the thermal instability of the materials, and the fabrication of epitaxial layers with parameters required for these purposes is connected with high costs. Besides that ion implantation offers the advantages already known from the silicon technology. However, in the compound semiconductors the variety of possible native defects is higher than in the elementary semiconductors, and the influence of the implantation parameters on the kind and concentration of defects produced during ion implantation is much more pronounced in these materials compared to silicon. As a consequence the annealing of damage as well as the electrical activation of the dopants are more complex processes than in silicon, and the choice of the annealing parameters requires information about kind and concentration of defects produced in the materials. The present paper gives a brief review about damage production connected with ion implantation in GaAs, GaP, InP and InAs. The influence of ion mass, ion fluence, dose rate and implantation temperature on the remaining damage is discussed. Additionally, an overview of the use of different annealing methods (conventional, laser and rapid thermal annealing) for the electrical activation of dopants, especially in ion implanted GaAs layers, is given.