Proceedings of SPIE - The International Society for Optical Engineering, Moscow, Russia, 27 - 31 May 2002, vol.5126, pp.381-385
The early studies have demonstrated, that the laminated crystals of the indium selenide (InSe) are highly sensitive photoconductors in a wide range of the temperature and light wavelength (0.35 ≤λ≤1.25 μm). In the present report we have studied opportunities of expansion of a spectral range (sensitization) of the IR-photosensitivity of these crystals to the longer wavelengths. It is established, that in the high-resistance InSe samples with good injecting contacts in superlinear section of the CVC (where the appreciable injection takes place) at rather low temperatures (T ≤150K) a considerable photosensitivity occurs and in impurity area (up to 3.50 μm with a maximum at λ=2.64 μm) a sensitization of the IR-photosensitivity for the investigated InSe single crystals by an electric field takes place. The dependence of this phenomenon on magnitude of the external electric field voltage, applied to the sample, as well as on the used contact materials, temperature, wavelength and intensity of an impurity light have been studied. Is has been shown, that a sensitization of the IR-photosensitivity of the InSe single crystals by an electric field and the particular features of this phenomenon are conditioned with the presence of trapping levels of a various type and large-scale dimensional discontinuities. The values of fundamental parameters of trapping levels, as well as discontinuities have been estimated.