Effects of channelling on the electrical properties of donor implanted GaAs

We have measured the electrical effects of implanting tin or tellurium ions into GaAs in random and channelling directions. Channelled implants produced higher electrical activities and broader electron concentration profiles than did random direction implants. To avoid channelling, samples should be carefully misaligned from a low-index direction for implant energies of less than about 100 keV, while implantations at higher energies require less stringent control of the implant direction.