Sharmistha Anwar; Shahid Anwar
Abstract
Present work is focused on various properties of thermally annealed tungsten nitride (WN) film. Tungsten nitride thin films on silicon (100) substrates were deposited via reactive magnetron sputtering technique. Initially Ar/N2 flow ratio was optimized by varying N2 gas flow between 5 to 25 sccm. 20:5 ...
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Present work is focused on various properties of thermally annealed tungsten nitride (WN) film. Tungsten nitride thin films on silicon (100) substrates were deposited via reactive magnetron sputtering technique. Initially Ar/N2 flow ratio was optimized by varying N2 gas flow between 5 to 25 sccm. 20:5 (Ar:N2) was found to be the best for W2N phase formation. Using optimized condition, a set of WN deposited and then annealed at different temperatures i.e. 200°C, 400°C and 600°C for two hours each. Various characterizations have been done using X-ray diffraction, four probe resistivity and nano-indentation test. XRD results suggest formation of pure W2N crystalline phase of the films with face centered cubic structure. The resistivity result shows the decrease of resistivity value with increase in annealing temperature. Nano-indentation results showed hardness and elastic modulus values at 5mn load does not vary much with annealing at different temperatures. Structural, mechanical and electrical studies showed that the samples were stable up to 600°C. Thus, tungsten nitride thin films will contribute as a material suitable for long time exposure at elevated temperature for application of cutting tools. Copyright © 2017 VBRI Press.
Sharmistha Anwar; Barada K. Mishra; Shahid Anwar
Abstract
Thermoelectric thin films of Bi2Te3 and Sb2Te3 were deposited by using sputtering technique. Structural characterizations of as deposited films were done by using X-ray diffraction (XRD), Energy Dispersive X-ray Analysis and electrical properties have been evaluated at room temperature by Seebeck coefficient ...
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Thermoelectric thin films of Bi2Te3 and Sb2Te3 were deposited by using sputtering technique. Structural characterizations of as deposited films were done by using X-ray diffraction (XRD), Energy Dispersive X-ray Analysis and electrical properties have been evaluated at room temperature by Seebeck coefficient and electrical resistivity measurement. These sputtered films were established to be polycrystalline and of desired single phase in nature with stoichiometric composition. The Seebeck coefficient and electrical resistivity of p-type Sb2Te3 thin film and n-type Bi2Te3 thin films were found to be about 111 μV/K, 8.25×10-5 Ω- m and −98.52μV/K, 5.87×10-6 Ω-m, respectively whereas to that of n-type Bi2Te3-Sb2Te3 multilayer having 5BL combination is −145μV/K, 9.31×10-5 Ω-m and 10BLcombination is −170 μV/K, 9.86×10-5 Ω-m. The power factor value has increased reasonably well in case of multilayer as compared to that of individual single layer, maximum power factor value 2.95×10-3 W/m K2 has been achieved for 10BL combination. These results indicate that good quality antimony telluride, bismuth telluride and their multilayer thin films can be grown easily by using sputtering technique. It also suggests that these types of nano-structuring (multilayer structure) in these categories of materials can be promissory engineering concept for the fabrication of micro-Peltier modules.
