A High Sensitivity UV Photodetector With Inkjet Printed ZnO/Nanodiamond Active Layers

Abstract

The single- and double-layered photodetectorsbased on ZnO and/or detonation nanodiamond (DND) have beendeveloped via a sequential inkjet printing on the interdigital elec-trode platform using a diamond and zinc oxide precursor ink. Themorphological structure of the deposited materials was visualizedand analyzed by scanning electron microscopy and atomic forcemicroscopy. The crystalline configuration and structural qualityof ZnO and nanodiamond were investigated by X-ray diffractionand Raman spectroscopy. The response, response time, andrecovery time were measured for different UV wavelengths(365, 385, and 405 nm), light intensities, temperatures, and biasvoltages. The ZnO/DND structure shows more than ten timeshigher response and faster reactivity in comparison with a single-layered photodetector. Photoresponsivity of the double-layeredphotodetector (ZnO/DND) is 0.35 A/W, whereas bare ZnOis about 0.039 A/W. The interaction between UV light andZnO/DND grains was investigated by two dimensional SilvacoTCAD simulation.