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代表当前技术的长波红外PbSnTe和短波红外HgCdTe光伏探测器阵列在稳态伽马通量、全剂量、电子通量、光子通量和脉冲电离环境中进行了辐射试验。这两类探测器对稳态伽马通量的瞬态响应都导致三种相互有关的结果,即产生单个脉冲,增加漏电流和增加方均根噪声。决定器件响应的基本上是结区的扩散长度。因此在PbTe衬底(它具有大的,约100微米的扩散长度)上的PbSnTe器件有比较大的响应。两类探测器的永久减退是受表面、界面或绝缘材料效应的控制。在HgCdTe探测器中,该机理表现为在探测器台面区附近的衬底表面反型。两类探测器的测量结果是漏电流增加和零偏压电阻降低。此外,由于器件有效面积增加,HgCdTe探测器的光学响应增加,以及PbSnTe器件的反向击穿电压降低。看来最能造成表面效应损伤的是对同时引起电离和位移作用的环境暴露。异质结PbSnTe探测器对脉冲电离的瞬态响应,其电流较同质结的计算饱和电流(它由开路电压和负载电阻调节)为大。与此同时,在PbTe衬底上的器件响应比根据器件体积计算的小(假设没有饱和)。也许这是异质结和PbTe材料的物理过程相结合而产生了这种结果。
Long-wave infrared PbSnTe and shortwave infrared HgCdTe photovoltaic detector arrays, representing the current technology, were tested for radiation in steady-state gamma flux, full dose, electron flux, photon flux and pulsed ionization environments. The transient response of both types of detectors to steady-state gamma fluxes results in three inter-related results, namely, single pulse generation, increased leakage current, and increased rms noise. Determine the device response is basically the junction of the diffusion length. Therefore PbSnTe devices on PbTe substrates (which have a large, diffusion length of about 100 microns) have a relatively large response. The permanent diminution of both types of detectors is controlled by the effect of the surface, interface or insulating material. In HgCdTe detectors, this mechanism appears as inversion of the substrate surface near the detector mesa region. The results of the two types of detectors are the increase of leakage current and the decrease of zero bias resistance. In addition, due to the increased effective area of the device, the optical response of the HgCdTe detector increases and the reverse breakdown voltage of the PbSnTe device decreases. It appears that the most damaging to surface effects is the environmental exposure to both ionizing and displacement effects. The transient response of the heterojunction PbSnTe detector to pulsed ionization is larger than the calculated saturation current of the homojunction (which is regulated by the open circuit voltage and load resistance). In the meantime, the device response on the PbTe substrate is small (assuming no saturation) as calculated from the device volume. Perhaps this is the result of the combination of the heterojunction and the physical process of the PbTe material.