Flexible Self-Powered ZnO Film UV Sensor with a High Response

Abstract

Response (on/off ratio) is one of the key parameters of ultraviolet (UV) sensors. In this paper, a kind of highly sensitive ZnO UV sensor with highly increased on/off current ratio was designed and developed. Under a weak UV intensity of 0.1 mW/cm², this ultrathin ZnO film-based UV sensor has an on/off current ratio of 1.3 × 10⁶ which is 3 times higher than the record value for ZnO-based UV sensors. In addition, it shows good flexibility and stable UV detection property during the bending process. When bending the sensor to a radius of curvature of about 18.5 mm, the sensor also shows high UV detection performance.