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The photoresponsive structures prepared by magnetron sputtering of ZnO on pSi substrates followed by vacuum evaporation of semitransparent Ni film on ZnO surface are investigated. The obtained NinZnOpSi structures show high sensitivity that sharply increases with increase in applied voltage. Under a bias voltage of 5 V, the responsivities at λ  390 nm and λ  850 nm were equal to 210 and 110 AW, which correspond to quantum efficiencies of 655 and 165, respectively. It is assumed that the observed strong response is attributed to internal gain in the NinZnOpSi phototransistor structure containing NinZnO Schottky contact as the emitter junction and nZnOpSi heterostructure as the collector junction. The response time of the device is ∼10–7 s. Alternative mechanisms of photocurrent multiplication in such structures are also discussed.

Investigations of photoelectrical properties of ZnO films are important scientific task for designing UV detectors for various applications. We report the positive role of nitrogen doping in increasing photoresponsivity of ZnO:Nbased detectors. It is suggested that nitrogen slightly deteriorates the structural quality of ZnO films and compensates intrinsic defects that increase photoresponsivity. Also, the spectral response of NiZnO:NnSi structures at different biases were considered.

Schottky barrier photodiodes obtained by vacuum evaporation of the semitransparent film over the surface of single crystalline Hg3In2Te6substrates pretreated by Ar ion bombardment. The responsivity maximum of the photodiodes is at the wavelength of 1.55 μm, corresponding to the transmission window in silica glass fiber with the minimal optical losses. The dark current in the diodes is determined by generationrecombination processes in the spacecharge region and quantitatively governed by the Sah–Noyce–Shockley theory. A comparison of the photoelectric parameters of Hg3In2Te6and Ge photodiodes is reported. The speed of the photodiode response is in the range 10–8s to 10–7s. © 2009 WILEYVCH Verlag GmbH & Co. KGaA, Weinheim