Bharathiar University

About: Bharathiar University is a education organization based out in Coimbatore, Tamil Nadu, India. It is known for research contribution in the topics: Thin film & Adsorption. The organization has 5812 authors who have published 8628 publications receiving 143934 citations. The organization is also known as: BU.

Nanostructured CrN thin films prepared by reactive pulsed DC magnetron sputtering

Abstract: High quality chromium nitride (CrN) films have been deposited onto silicon (1 0 0) substrates using pulsed DC magnetron sputtering of pure Cr target at different gas mixtures of argon and nitrogen and in the substrate temperature range 303–973 K. At low N 2 flow rates ( 2 N and CrN) are obtained. At higher flow rates, in the range of 10–25 sccm, only cubic CrN phase is obtained. The films prepared at different substrate temperatures and at 10 sccm of nitrogen flow rate indicated the formation of cubic CrN phase at room temperature and the phase formed is found to be stable up to 973 K. The deposition of the films as a function of nitrogen flow rate and substrate temperatures indicated that the good quality crystalline films could be formed at 773 K, 10 sccm of nitrogen flow rate. The Cr 2p 3/2 and N 1s of XPS spectra also confirmed the formation of CrN phase. Determination of the texture coefficients of the CrN films as a function of substrate temperature showed that the preferred orientation changes from [1 1 1] to [1 0 0]. Deposition as a function of nitrogen flow rates and substrate temperatures showed significant changes in the morphology and RMS surface roughness, which could be related to the difference in the growth mechanism of the CrN films. Measurement of nanomechanical properties on typical films deposited on titanium modified stainless steel substrates at optimum conditions show hardness of 12 ± 1.81 GPa, Young's modulus of about (250 ± 51.28 GPa) and coefficient of friction of 0.16.

Characterization of vacuum-evaporated ZnSe thin films

Abstract: ZnSe thin films were deposited onto glass substrates under a vacuum of 3×10 −5 Torr by using vacuum evaporation technique. Rutherford backscattering spectrometry technique is used to measure the composition and thickness of the deposited films. The composition of the deposited films is found to be nearly stoichiometric. The X-ray diffractogram reveals a preferential orientation along (1 1 1) direction, and the structural parameters such as crystallite size, dislocation density, strain and lattice parameters are calculated, and also the effect of film thickness and substrate temperature of the deposited films was also discussed. It is observed that the crystallite size increases from 20.11 to 55.56 nm with the increase in film thickness. The X-ray diffraction (XRD) studies show that the structure of the deposited films is cubic. The crystalline nature of the deposited films is also confirmed by Raman scattering measurements. In the optical studies, optical band-gap values decrease with the increase in film thickness and substrate temperatures. In the DC conduction studies, the conduction mechanism is found to be exponential trap distribution and the results are discussed.