碲镉汞光导器件振动噪声

Vibration noise in HgCdTe photoconductive devices

利用振动台和频谱分析仪对碲镉汞中波光导器件的噪声进行了研究.随机振动的实验结果表明,振动环境中测量到的噪声随着随机振动功率谱密度的增大而线性增加,其比例系数是分段的,当振动功率谱密度小于0.01 g2/Hz,为32μVHz0.5/g2,大于0.01 g2/Hz,为80μVHz0.5/g2.对实验结果进行了初步分析,认为振动能量以一定的内耗系数转化为热能,以声子的形式在碲镉汞材料内传递,改变了晶格振动的能级,影响了材料的散射特性,从而影响器件的输运特性、电阻率等电学特性,产生了附加的振动噪声.

The noise of HgCdTe medium - wave photoconductive devices was studied by vibration text table and spec- trum analyzer. The random vibration experimental results showed that the noise measured in vibration environment in- creased linearly with the increase of vibration power spectrum density （PSD）. The linear dependence can be divided into two parts. The coefficient is 32 μVHzl/2/g2 or 80 μVHzl/2/g2 with the vibration PSD of 0.01 g2/Hz as the kink point. In order to explain the experimental results, we suggested that the vibration energy is absorbed with a certain coef- ficient by HgCdTe material and transformed into thermal energy. This gives rise to an increased scattering of charge car- ders by the phonons in the material, eventually produces an extra vibration noise in the device.