ZnO/p-Si异质结的I-V及C-V特性研究

Study on I-V and C-V Characteristic of ZnO/p-Si Heterojunction

摘要:

通过磁控溅射Al掺杂的ZnO陶瓷靶，在p-Si片上沉积n型电导的ZnO薄膜而制备了ZnO/p-Si异质结，并通过测试其光照下的I-V、C-V特性对其光电特性以及载流子输运特性与导电机理进行了研究。研究表明ZnO/p-Si异质结存在良好的整流特性与光电响应，可以广泛应用在光电探测和太阳电池等领域。由于在ZnO/p-Si异质结界面处的导带补偿与价带补偿相差太大的缘故，在正向电压超过1V时，导电机理为空间电荷限制电流导电。同时，研究表明ZnO/p-Si异质结界面存在大量界面态，可以通过减小界面态进一步提高其光电特性。

Abstract:

In this article, a n-type conductance ZnO thin film was deposited on p-Si film by magnetron sputtering Al-doped ZnO ceramic target, and then ZnO/p-Si heterojunctions were preparated. The photoelectric properties, carrier transport properties and conductive mechanism were studied by testing the I-V and C-V characteristics with and without illumination. The results show that ZnO/p Si heterojunctions obtain good rectifying properties and photoelectric response, and can be widely used in photoelectric detection and solar cells. As the conduction band and valence band offset in the ZnO/p-Si heterojunction is too big, the current transport mechanism is dominated by the space charge limited current (SCLC) conduction when the forward voltage exceeds 1V. And it is also suggested the existence of a large number of interface state in ZnO/p-Si heterojunction, and the photoelectric properties can be further improved by reducing interface states.