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

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。

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 1 V.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.