4H-SiC紫外光电探测器光电特性随温度变化的研究

利用光电流谱法研究了300K到60K温度范围内的p-i-n结构4H-SiC紫外光电探测器的暗电流及相对光谱响应特性。研究发现随着温度的降低，探测器的暗电流和相对光谱响应都逐渐减小；而且，反向偏压越高，暗电流减小的速率越大。在零偏压下，随着温度的降低，器件的温度从300K降低到60K时，相对光谱响应的峰值波长先向短波方向移动，后向长波方向移动，在60K时移至从272nm附近移至282nm附近；同时观察到探测器的相对光谱响应范围略有缩小，。此外，我们对器件并讨论了温度变化对器件p、i、n各层产生的光电流随温度变化的机理进行讨论，提出了可以通过减少i层缺陷和适当减小n层的掺杂浓度的方式来提高器件的相对光谱响应。

Photoelectric properties of 4H-SiC UV photodetector at various temperatures

The dark current and relative spectral response of 4H-SiC ultraviolet p-i-n photodetector were investigated with the temperature decreasing from 300 K to 60 K by photocurrent measurement.It is found that the dark current and relative spectral response of the device declined during the whole period and that the higher the reverse bias voltage is,the faster the falling rate of dark current are.At the reverse bias of 0 V,when the temperature dropped,the peak response wavelength of the device firstly shifted sl...