氮化镓肖特基结紫外探测器的异常特性测量

测量了CaN肖特基结紫外探测器在有、无光照下的I-V异常特性。分别用362nm和368nm光束对有源区进行横向扫描，得到了光照不同部位时探测器在无偏压、2V反向偏压下的电流。紫外光照到肖特基结压焊电极附近及透明电极边沿附近区域时，探测器在反向偏压下有较大增益，空间响应均匀性变差，在禁带内有两个增益响应峰波长——364nm和368nm。探测器在810nm光照射下，反向偏压下的光响应增益、持续光电导存在光淬灭现象。探测器紫外光照完后，俘获中心及表面陷阱所俘获的部分电荷在高反向偏置电压下老化可以通过隧穿或发射效应释放出来，经过高反向偏置电压老化完后的探测器在同一低反向偏置电压下暗电流比老化前的要小。测量结果为GaN器件的研制提供了参考数据。

Abnormal characteristic measurement of GaN Schottky junction UV detectors

Abnormal I-V curves of GaN Schottky junction UV detectors were measured when they were illuminated with and without UV light of different wavelengths. The currents of the detectors at no bias voltage and reverse bias voltage of 2V were obtained when they were illuminated by light beams of 362nm and 368nm scanning across the active region of the detectors, respectively. Measurement results show that detectors at reverse bias voltage exhibit high gain with UV light beam illuminating the region near the edge transparent electrode and near the Schottky junction pad, and the spatial responsivity is non-uniformity. The detectors at reverse bias voltage exhibit high gain peak at 364nm and 368nm wavelength near the band edge. The high gain and persistent photoconductivity of the detector at reverse bias voltage can be quenched by 810nm light illumination respectively(optical quenching). Electrons and holes captured by trap centers after illumination can be emitted by high reverse voltage aging. The dark current of the detector at low reverse voltage after high reverse voltage aging is less than that before aging.