MgxZn1-xO films have been grown by radio frequency (RF) magnetron sputtering technique with combinatorial targets, and the solar-blind photodetectors based on the films have been fabricated. As a representative, the solar-blind photodetector based on Mg0.45Zn0.55O film exhibits an ultra-high responsivity of 031 A/W at 3 V bias, with a typical sharp cutoff wavelength at 284nm. The excellent responsivity characteristics make a contribution to a detectivity performance of 1.14 x 10(13) cm Hz(1/2)W(-1). Furthermore, the device also performs a very low dark current about 2.67 pA at 10 V bias. (C) 2015 Elsevier Ltd. All rights reserved.