碲镉汞光伏型探测器的氢化处理研究

STUDY OF HYDROGENATION ON HgCdTe PHOTOVOLTAIC DETECTORS

利用氢等离子体方法研究了氢化处理对碲镉汞光伏型红外探测器性能的影响,发现对ZnS介质层钝化的器件进行氢化处理后,器件的信噪比和零偏电阻有显著的改善.通过采取在氢化过程中进行光刻胶保护的方法,发现氢化作用主要发生在注入区域之外的P区一侧;通过SIMS测试分析发现氢化过程中H离子可以穿过ZnS层到达ZnS与碲镉汞的界面处.分析认为氢离子对ZnS和碲镉汞的界面产生钝化,降低了界面态密度,减弱了P型区的表面漏电,提高了PN结的击穿电压和结电阻,从而改善了器件的性能.

The hydrogenation of HgCdTe photovohaic（PV） detectors by H-plasma was investigated. It was found that the ratio of signal to noise and resistance at zero bias of the detectors passivated with ZnS were obviously improved after hydrogenation. Via a comparative study that the P-type zone was protected by photoresist or not, it was infered that hydrogenation effects mainly happened on the P-type zone of the detectors. By SIMS analysis H^＋ was found to penetrate through ZnS and reach the interface between ZnS and HgCdTe, and the improvement of performance after hydrogenation was due to the passivation of interface states by H ions, which resulted in a decrease of interface states and surface leakage current, thus the break-down voltage and resistance of the junction were increased.