Ultraviolet photodetector fabricated from metal-organic chemical vapor deposited MgZnO

Wurtzite Mg(x)Zn(1-x)O thin films were grown on sapphire substrates by low-pressure metal-organic chemical vapor deposition. The as-grown films show clear exciton absorption at room temperature until the composition x=0.25. A representative metal-semiconductor-metal structured photodetectors were fabricated from Mg(0.06)Zn(0.94)O film showed a peak responsivity of about 14.62 A/W at 340 nm, and the ultraviolet-visible rejection ratio (R340 nm/R400 nm) was more than two orders of magnitude at 3 V bias. The photodetector showed fast photoresponse with a rise time of 20 ns and a fall time of 400 ns