Spectral and photoelectric characteristics of the gamma irradiated intrinsic oxide-InSe heterostructures obtained under different conditions

• Published in: Radiation physics and chemistry (Oxford, England : 1993) England : 1993), 2016-09, Vol.126, p.90-94
• Main Author: Sydor, OM
• Format: Article
• Language: English
• Subjects: Fluence; Heterostructures; High speed tool steels; Irradiation; Oxidation; Photoelectricity; Photosensitivity; Spectra
• ISSN: 0969-806X
• DOI: 10.1016/j.radphyschem.2016.05.017

The investigations of photoelectric characteristics and photoresponce spectral dependences were carried out for intrinsic oxide-InSe heterostructures (HSs) and their changes induced by bremsstrahlung gamma -quanta with an energy of 1-34 MeV at fluences of 10 super(12)-10 super(15) cm super(-2). The thermal oxidation of the p-InSe:Cd substrates was carried out at a temperature of 420 degree С . For three selected groups of samples the duration of the process was 15 min, 60 min, and 96 h. At a short-term oxidation (15 and 60 min) a layer of In sub(2)O sub(3) appears. The only difference between the samples of these two groups is a higher photosensitivity in the range of energy 1.25-2.8 eV of the HSs obtained after the 60 min oxidation. At the long-term oxidation the photoresponce spectra eta (h nu ) of the obtained HSs are characterized with a sharp short-wavelength decrease at h nu approximately equal to 2.0 eV. It is established that the intrinsic oxide films act as transparent barrier electrodes in the corresponding HSs and are low-sensitive to gamma -irradiation in the all range of fluences. The shape of the photoresponce spectra for all the gamma irradiated HSs remains practically the same. However, it was found: (i) some decrease of photosensitivity at the long-wavelength edge, (ii) decreasing the width of eta (h nu ) at half-height, (iii) the appearance of the exciton peak, (iv) the improvement of a slope of the low-energy edge of the photoresponce spectra with increasing irradiation dose whereas at the maximum fluence this parameter decreases, and (v) the slight extension of the spectral sensitivity to the short-wavelength range for the structures obtained after oxidation for 96 h. The photoelectric parameters of the intrinsic oxide-p-InSe HSs, open circuit voltage V sub(oc), short-circuit current J sub(sc), current S sub(I lambda max) and voltage S sub(V lambda max) sensitivities become only improved after irradiation with the fluences 10 super(12)-10 super(13) cm super(-2). At the maximum fluence a small decreasing of the values of V sub(oc) and J sub(sc) was detected except for the structures obtained after oxidation for 15 min. An increase of the S sub(I lambda max) and S sub(V lambda max) sensitivities in comparison with the initial value were found for all the HSs even at the maximum fluence except for the structures obtained by a long-term oxidation.