Abstract
Zn0.9Mg0.1O/ZnO p-n junctions were grown by pulsed laser deposition at ø500 °C on bulk n-type,
s100d, nonpolar, a-plane ZnO substrates. No postgrowth annealing was performed, with the P-doped
ZnMgO showing p-type conductivity shole density ,1016 cm−3, mobility ,6 cm2 V−1 s−1d in the
as-grown state. Front-to-back p-n junctions were fabricated with Ni/Au used as the p-Ohmic
contact and Ti/Au as the backside n-Ohmic contact. The p contacts showed improved
characteristics after annealing up to 400 °C, but the n contacts were Ohmic as deposited. The
junctions showed rectifying behavior up to 200 °C. The forward turn-on voltage was ,6.5 V at
25 °C. The simple, low-temperature growth and processing sequence show the promise of ZnO for
applications in transparent electronics and UV light emitters