In light of the trend of moving to higher storage densities, it is
clear that more effort must be expended to develop shorter wavelength optoelectronic
devices. We are applying our efforts to the developement of wide-bandgap
oxide semiconductors such as ZnO (shown right).
ZnO has a room temperature bandgap of approximately 3.4 eV and can be allowed
with Mg for bandgap engineering purposes. We are growing ZnO by both molecular
beam epitaxy and laser ablation. Outstanding problems include p-type
doping as well as optimization of device structures. We are growing ZnO
on a-sapphire substrates.