Temperature and pulse duration effects on the growth of MgZnO via pulsed metal organic chemical vapor deposition

Abstract

The effect of substrate temperature (TS) and pulse duration (PD) on Mg incorporation, surface quality, and photoresponse properties of MgZnO films grown via PMOCVD were studied. Films grown at TS ranging from 500 to 700 °C but at identical PDs had band gaps varying from 3.38 to 3.87 eV, corresponding to Mg content between x = 0.06 and 0.27. The film with Mg content of 0.27 was the smoothest and achieved at 630 °C-optimal TS. Additionally, pulse time effect was studied by growing films at the same TS but different PDs. A film grown at PD of 12 s has incorporated ∼40% higher Mg than one grown in a continuous mode (PD → ∞), indicting the cruciallity of PMOCVD to realize high Mg film. The peak response spectra of photodetectors were also varied with TS and PD, in accordance with Mg content in the films.