ABSTRACT
In this chapter, the author considers diffusion of those elements which give rise to donor states close to the conduction band in III–V semiconductors. The diffusion of sulphur in GaAs has been studied by a number of workers. Early work was largely concerned with the sulphide layer which can form on the surface of the semiconductor during a diffusion experiment in which sulphur is diffused from the vapour phase. Most investigations of the diffusion of selenium and tellurium in III–V compounds were carried out some years ago. High temperature diffusion of silicon in GaAs was first studied by Vieland and Antell, both using the p–n junction technique to assess depth of diffusion. Experiments were carried out over a range of ambient phosphorus pressure and it was found that the diffusion coefficient varied inversely as the square of the phosphorus pressure.
