MgxZn1-xO-based photodetectors covering the whole solar-blind spectrum range

A series of Mg(x)Zn(1-x)O thin films has been prepared by metalorganic chemical vapor deposition and metal-semiconductor-metal structured ultraviolet photodetectors are fabricated from these films. The cutoff wavelengths of the photodetectors can cover the whole solar-blind spectrum range (220-280 nm) by varying Mg content in the Mg(x)Zn(1-x)O thin films. As a representative, the photodetector fabricated from Mg(0.52)Zn(0.48)O shows an ultraviolet/visible rejection ratio of about four orders of magnitude, and the dark current is 15 pA at 10 V bias. These results demonstrate that high-performance photodetectors operating in the whole solar-blind spectrum range can be realized in Mg(x)Zn(1-x)O films. (C) 2008 American Institute of Physics. [DOI: 10.1063/1.3002371]