Diffusion properties of Al in ZnTe substrates

In order to fabricate intrinsic pn junctions in p-type ZnTe substrates. for realizing pure-green light-emitting diodes, Al was used as the diffusion s pecies. We found that the Al diffusion region is observed as a dark region image by scanning electron microscopy. Al was diffused over a wide range of annealing temperatures and times. It was found that the activation energie s of Al diffusion into p-type ZnTe substrates were 1.9+/-0.1 eV and the dif fusion coefficient was given by D = 20 exp(-1.9/kT) cm(2)/s. (C) 2001 Ameri can Institute of Physics.