Showing papers by "V. Damodara Das published in 1981"
TL;DR: In this article, it was shown that thermoelectric power is independent of temperature and is also independent of thickness, over the range of temperatures and thicknesses investigated, and the results were discussed on the basis of size effect and temperature effect theories.
Abstract: Tellurium thin films of thicknesses between 25 and 200 nm have been vacuum-deposited on glass substrates at room temperature in a vacuum of 5×10−5torr. The thermoelectric power measurements on these films have been carried out, after annealing, in the temperature range from 300 to about 500 K. It is found from the study that thermoelectric power is independent of temperature and is also, apparently, independent of thickness, over the range of temperatures and thicknesses investigated. The results are discussed on the basis of size effect and thermoelectric effect theories.
26 citations
TL;DR: In this paper, electrical resistivity and Hall effect measurements have been made on vacuum evaporated Bi 90 Sb 10 alloy films of various thickness (350 A to 4500 A), in the temperature range of 77 to 510 K.
10 citations
TL;DR: In this paper, the resistance of bismuth thin films of thickness 720 A have been vacuum deposited at various substrate temperatures on glass substrates and their resistances are recorded as a function of temperature after annealing the films at 200°C.
9 citations
TL;DR: In this article, it was shown that resistivity oscillates with thickness both for unannealed and annealed films and that the same kind of oscillatory behaviour with thickness is also observed in the case of defect resistivity.
5 citations
TL;DR: In this paper, Bismuth antimonide (composition 80∶20) alloy thin films have been prepared by vacuum deposition at different substrate temperatures and, after annealing, their resistances have been recorded as a function of temperature, between 77 K and 500 K.
Abstract: Bismuth antimonide (composition 80∶20) alloy thin films have been prepared by vacuum deposition at different substrate temperatures and, after annealing, their resistances have been recorded as a function of temperature, between 77 K and 500 K. The observed resistance against temperature behaviour of the films, and the effect of thickness and substrate temperature during deposition of the films, has been explained by considering that these films behave as semiconductors; the overlap between valence and conduction bands being removed due to the presence of antimony, the influence of a quantum size effect and the fact that the grain size of the films formed is a function of thickness and substrate temperature.
5 citations
TL;DR: In this paper, the authors measured the electrical conductivities of tin and copper thin films of different thicknesses in the coalescence thickness range (160, 210 and 260 A) and found that the application of an electric field of less than 60 V cm -1 decreased the resistance of the films.
5 citations
TL;DR: In this paper, Vand's theory was used to correlate changes in electrical conductivity during heat treatment with the changes in defect concentration in the indium thin films of thicknesses 625±25 and 500±25 A.
4 citations
TL;DR: In this article, annealed Bi 60 Sb 40 alloy thin films of various thicknesses vacuum deposited at different substrate temperatures have been carried out from about 80 K to 500 K. The observed variation in resistance with temperature has been explained on the basis of impurity conduction, band to band transition, grain boundary barrier activation of carriers and metallic behaviour in different regions of temperature.
4 citations
1 citations
TL;DR: In this article, the resistivity and temperature coefficient of resistance of vacuum deposited thin films of InBi and In 2 Bi of different thicknesses have been measured after annealing and the resistance measurements have also been carried out in situ during the growth of the films as the thickness increases.