Ultraviolet detectors based on ZnO:N thin films with different contact structures

Abstract

Al/ZnO:N/Al and Ni/ZnO:N/Al diode photodetectors fabricated by dc magnetron sputtering of ZnO:N films on p-Si substrates are studied. The photocurrent-to-dark current ratio equal to 250 at λ = 390 nm and the time constant of photoresponse about 10 μs for Al/ZnO:N/Al structures with 4 μn interdigital spacing was achieved. The Ni/ZnO:N/Al diode structure has the rectification ratio ≈ 102 at bias 1 V, the maximal responsivity about 0.1 A/W is observed at 365 nm, and the measured time constant of photoresponse is about 100 ns.