Au/p-CZT晶体的光致发光以及电学性能研究

Study on PL and Electrical Properties of Au/p-CZT Crystal

对比了CZT晶片经腐蚀与钝化表面处理的PL谱,结果表明NH4F/H2O2作为CZT晶体表面钝化剂,钝化后CZT晶体表面陷阱态密度减小到最低程度,同时减小了与Cd空位复合有关的深能级杂质浓度。用Agilent 4339B高阻仪进行CZT晶片I-V特性测试以及Agilent 4294A高精度阻抗分析仪进行CZT晶片的C-V特性测试,结果表明钝化均能不同程度提高Au/p-CZT接触的势垒高度,减小了漏电流。主要原因是在CZT表面钝化生成的TeO2氧化层增加接触势垒高度,并减小了电荷因隧道效应而穿过氧化层的几率。

By comparing the photoluminescence （PL） spectrum of etching and passivafion surface of the p-CZT, potoluminescence （PL） spectra confirmed that using NH4F/H2O2 as agent, the passivation treatment minimized the surface trap state density and decreased the deep level defects related to recombination of Cd vacancies. I-V and C-V characteristics of Au/p-CZT contacts with different surface treatments were measured by Agilent 4339B high resistance meter and agilent 4294A precision impedance analyzer, respectively. It was shown Au/p-CZT and decrease the leakage that etching and passivation could increase the barrier height of the current. The major reason was that passivation increased the barrier height of Au/p-CZT contacts and possibility for electrons through the TeO2 oxide was smaller.