Zn diffusion in GaAs obtained by a simple open-tube technique

Zn diffusion into 2-in.-diam semi-insulating GaAs wafers has been carried out by a simple, open-tube diffusion method using a commercially available GaAsZn solid source and without surface coating or encapsulation. High-quality (μ=75–100 cm2/V s) layers with a flat carrier concentration and sharp cutoff Zn distribution have been obtained. The p-type layers obtained by this method are uniform across the wafer, and the technique can be easily scaled up. Selective diffusion of Zn was also demonstrated with this technique, using a plasma-deposited Si3N4 as a diffusion mask.