Published online by Cambridge University Press: 15 February 2016
Pulsed metal organic chemical vapor deposition (PMOCVD) was used to grow high Mgcontent, high quality, wurtzite MgxZn1-xO (MgZnO)epitaxial film to realize photodetectors and emitters in the solar blindspectral window. MgZnO films with various Mg contents were deposited on c-planeAl2O3 with and without AlN buffer layer. The band gapof the films range from 3.24 eV to 4.49 eV, corresponding to fraction of Mgbetween x=0.0 to x=0.51, asdetermined by Rutherford backscattering spectroscopy (RBS). Cathodoluminescence(CL) measurement showed a linear blue shift in the spectral peak position ofMgxZn1-xO with an increase in x. Nomulti-absorption edge or CL band splitting was observed, indicating the phasepurity of the films and was confirmed by XRD analysis. The surface quality ofthe films has improved with the increase in Mg content. To the best of ourknowledge, the current result shows the highest Mg content(x=0.51), high quality, single phase wurtzite MgZnOepitaxial film ever grown by MOCVD. This is realized due to the non-equilibriumbehavior of PMOCVD in which radicals that are formed during the growth processwill have insufficient time to reach equilibrium.