Effect of composition on steady state and transient photoconductivity in isocoordinated InxSb30−xSe70 (0 ≤ x ≤ 25) chalcogenide films

• Published in: Journal of materials science. Materials in electronics Vol. 28; no. 19; pp. 14202 - 14208
• Main Authors: Sharma, Shaveta, Sharma, Rita, Kumar, Praveen, Thangaraj, R., Asokan, K., Mian, M.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.10.2017; Springer Nature B.V
• Subjects: Alloys; Carrier recombination; Chalcogenides; Characterization and Evaluation of Materials; Chemistry and Materials Science; Composition effects; Decay rate; Evaporation; Exponential functions; Glass substrates; Luminous intensity; Materials Science; Optical and Electronic Materials; Photoconductivity; Photoelectric effect; Photoelectric emission; Physical properties; Raman spectroscopy; Semiconductors; Solar generators; Spectrum analysis; Steady state; Thickness; Transient photoconductivity
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-017-7277-8

The study of steady state and transient photocurrent measurement provide important information about carrier generation and recombination phenomena in various semiconducting systems for photo-sensor device applications. In the present work, the composition dependent analysis of photocurrents was studied for thermally evaporated Se-rich In x Sb 30−x Se 70 films of average thickness 800 nm. The indirect optical gap has been calculated from the transmission and reflection data and the variation of molecular units was studied from the Raman spectroscopy. The initial rise of photocurrent sharply to approach a steady state value during illumination and fast decay to a constant persistent current after stopping the illumination has been observed. The intensity dependence of photocurrent obeys the power law I Ph  = F γ , where the value of exponent tells about the recombination process. The decay of photocurrent has been fitted with stretched exponential function for different compositions and at different light intensities. These results are important for the development of low cost photo absorbers for solar cell applications and visible region responsive photo sensor devices.