Transparent Ultraviolet Sensors Based on Magnetron Sputtered ZnO Thin Films

Ultraviolet (UV) sensors have variety of applications. In this work, a new transparent UV sensor is developed based on zinc oxide (ZnO) films. The ZnO films with 350 nm thicknesses were fabricated on glass substrates by using direct current (DC) plasma magnetron sputtering technique. The ZnO UV sensors are characterised by using current-voltage (I-V) measurements at room temperature. The current is measured by applying small bias voltage under the white light, UV light (325 nm), and dark condition and the photocurrent responses extracted from the I-V measurements are compared. The transparent UV sensors based on ZnO films deposited at high substrate temperature of 450 °C exhibit most significant photocurrent response under UV irradiation.