SiO2钝化膜对i-GaN肖特基探测器性能的影响

在采用金属有机化学气相沉积（MOCVD）生长的非故意掺杂的i-GaN材料上制备了平面结构肖特基探测器；利用磁控溅射在探测器的两个电极隔离区域生长SiO2钝化膜；并对这些器件的性能进行了表征。通过与没有SiO2钝化膜的肖特基探测器性能比较，结果表明：SiO2钝化膜能显著地降低器件的反向漏电流，同时并不影响器件的正向开启电压；在光波长范围为300～365nm，探测器的响应率显著地提高。产生这些变化可能是SiO2钝化膜减少了肖特基探测器电极隔离区域表面缺陷的缘故。

Effects of SiO2 Passivation Layer on Performances of i-GaN Schottky Photodetectors

The lateral-geometry Schottky photodetectors have been fabricated on the unintentionally doped i-GaN grown by MOCVD. A SiO2 passivation layer has been grown on the zone between the ohmic contact and the rectifying contact by the magnetron sputtering. The performances of Schottky photodetectors have been characterized. Through comparison between the performances of Schottky photodetectors with and without SiO2 passivation layer,the results show the reverse leakage current of the photodetectors with SiO2 passivation layer is greatly reduced, and its forward turn-on voltages are not affected,and the spectral responsivity of the photodetectors is obviously improved at light wavelength between 300 and 365 nm. These may be attributed to SiO2 passivation layer which reduces the surface defects of electrodes spacing zone for the Schottky photodetectors.