Low power consumption UV sensor based on n-ZnO/p-Si junctions

Abstract

We report on the manufacture of low power consumption UV sensor based on n-ZnO/p-Si Junction. The ZnO thin film was prepared through RF sputtering process. The X-ray diffraction analysis and scanning electron microscopy reveal that the prepared ZnO films exhibit single diffraction peak at a Bragg angle of approximately 34.28° with a homogeneous distribution of nanosized structures. The pn junction exhibit good rectifying behaviour with rectifying ratio of approximately 800 at ± 2 V. At zero bias voltage, the prepared UV photodiode shows the highest photo-to-dark current ratio with a stable dynamic behaviour under the illumination of 360 nm UV light. The prepared UV photodiode show dual polarity behaviour with different proposed sensing mechanisms.