Improving performance of the MgZnO ultraviolet photodetectors by changing the interdigital electrode width
Highlights: • The different electrode width of the metal-semiconductor-metal photodetectors are fabricated by the radio frequency magnetron sputtering technique. • The responsivity and the dark current of the photodetectors will vary with the electrode width. • The main reason of the interesting phenomenon is the change of the density of the carriers. - Abstract: We grow the Mg{sub 0.24}Zn{sub 0.76}O thin film onto a quartz substrate by the radio frequency magnetron sputtering technique. Planar geometry metal-semiconductor-metal structured ultraviolet detectors were fabricated by conventional ultraviolet lithography and wet etching on the Mg{sub 0.24}Zn{sub 0.76}O thin films. To improve the performance of the device, three kinds of photodetectors with different electrode width were fabricated, after a series of tests on those device, it is amusing to find an interesting phenomenon, the Mg{sub 0.24}Zn{sub 0.76}O photodetectors with different electrode width have a great influence on the performance of the whole device. The Mg{sub 0.24}Zn{sub 0.76}O photodetectors that own larger electrode width had a higher responsivity and lower dark current than the photodetectors own littler electrode width. These interesting results are very meaningful for the photodetector industry.