Realization of cathodoluminescence in the 180 nm spectral range by suppressing thermal stress in mist chemical vapor deposition of rocksalt-structured MgZnO films

Abstract

Rocksalt-structured (RS) Mg x Zn1-x O films with x=0.65-1.0 were grown on MgO (100) substrate by the mist chemical vapor deposition method. Comparative study for the RS-Mg0.92Zn0.08O films grown under slow and rapid-cooling rates apparently showed simultaneous reductions in the surface pit density, full width at half maximum values for the X-ray diffraction peak, and defect-related cathodoluminescence (CL) for the film grown under the slow-cooling rate. CL spectra for the RS-Mg x Zn1-x O films grown under the slow-cooling rate eventually showed near-band-edge emission peaks in 180-190 nm spectral range for MgO molar fraction x≥0.92 at room temperature.

Bandgap engineering of spinel-structured oxide semiconductor alloys

“…MgAl 2 O 4 has a large bandgap (∼7.8 eV) and good mechanical, chemical, and optical properties [21]. In particular, because the bandgap and optical properties are similar to those of MgO [22], bandgap engineering, such as Mg-rich MgZnO alloys, can be expected [23][24][25][26][27][28][29][30][31][32][33][34][35][36]. However, these ultra-wide bandgap (UWBG) oxide materials still face challenges with regard to ambipolar doping [37][38][39].…”