Showing papers by "V. Damodara Das published in 1998"
TL;DR: In this article, the results on (Bi 0.25 Sb 0.75 ) 2 Te 3 alloy films agree with the prediction of size effect theories, and the effective mean free path model with perfect diffuse scattering is used for the analysis of the data.
30 citations
TL;DR: In this paper, photoelectrochemical properties of thin polycrystalline thin films of n-CdSe 0.5 Te 0.5 alloy were characterized by X-ray diffraction and optical absorption studies, and it was found that the films are n-type and show photoactivity in 2 M Kl + 20 mM I 2 /C electrolyte.
19 citations
TL;DR: In this paper, the effect of substrate on the working of n-CdSe 0.7 Te 0.3 thin-film/polysulphide photoelectrochemical (PEC) solar cells has been investigated in detail.
17 citations
TL;DR: In this article, the thickness dependences of electrical resistivity and thermoelectric power of Bi2Te2Se1 of various thicknesses have been analyzed using the effective mean-free path model.
Abstract: Thin films of Bi2Te2Se1 of various thicknesses have been deposited on clean glass plates using the flash evaporation technique. Electrical resistance and thermoelectric power measurements have been carried out on these films in the temperature range 300–485 K. The thickness dependences of electrical resistivity and thermoelectric power of the films have been analyzed using the effective mean-free path model. The thickness dependence of activation energy of the films is explained by Seto’s polycrystalline model. Various material parameters such as mean-free path and Fermi energy have been calculated from the analysis of experimental data. The thermoelectric power factor of the films has been calculated using the measured electrical resistivity and thermoelectric power values.
11 citations
TL;DR: In this paper, the thickness dependence of electrical resistivity has been analyzed using the effective mean free path model and important material constants like the mean free-path and the electron concentration have been evaluated.
7 citations
TL;DR: In this paper, the authors measured electrical resistance in vacuum (2×10 −5 ǫ) as a function of time and found that the resistance increased as pressure increased, and the resistance varied with the altitude of the vacuum chamber.
3 citations
TL;DR: In this article, vacuum deposited thin films of n-CdSe0.7Te0.3 of 5000 A thickness have been characterized by X-ray diffraction (XRD) for structural analysis, by energy despersive analysis of X-rays (EDAX) for compositional analysis and the scanning electron microscopy (SEM) for surface studies.
Abstract: The vacuum deposited thin films of n-CdSe0.7Te0.3 of 5000 A thickness have been characterized by X-ray diffraction (XRD) for structural analysis, by energy despersive analysis of X-rays (EDAX) for compositional analysis and the scanning electron microscopy (SEM) for surface studies. Similar films have been deposited on Indium Oxide precoated microslide glass plates and the photoelectrochemical properties of n-CdSe0.7Te0.3/polyiodide junction are investigated for suitability for solar energy conversion by I–V measurements in the dark. Also, the carrier concentration and flat band potential have been calculated from the space charge capacitance vs voltage measurements. The minority carrier diffusion length, Lp has been determined using Gartner's model. Using the Mott-Schottky plots, the energy band diagram at flat band condition has been constructed. The occurrence of high quantum efficiency and high power conversion efficiency have been explained.
2 citations
01 Apr 1998
2 citations