Reduction of Schottky Barrier Height, Turn on Voltage, Leakage Current and High Responsivity of Li Doped ZnO Nanorod Arrays Based Schottky Diode

Abstract

1D ZnO nanostructures have been considerable interests due to their unique structures and properties as well as potential applications as building blocks of nanodevices. The Zn1−xLixO NR arrays were grown on p-Si substrate by an inexpensive environment friendly hydrothermal process followed by forming Au/Zn1−xLixO NRs Schottky photodiodes. The diodes show excellent rectifying property in dark and the rectification to be 1.19 × 102 and 6.26 × 102 at 2.4 V, for Au/ZnO and Au/LZO NRs diodes, respectively. It is interesting that Li doped diode shows negative shift of the turn on voltage (Von) and the rapidly increasing forward current as well as low leakage current which are of great benefit to minimize the power loss and an improving switching characteristics of rectifier devices. The obtained ideality factor is greater than unity. The value of barrier height obtained from I–V measurements is smaller than the value obtained from C–V measurements. The responsivity is higher for Li doped diode (0.13 A/W) than undoped (0.05 A/W) even the commercial GaN UV detector (0.1 A/W). Thus, good crystallinity and excellent Schottky diode rectifying properties of Au/ZnLiO NRs diode on p-Si substrate, enabling efficient electronics nanodevices and nanoscale UV-photodetection sensors.