The role of gas direction in a modified Grimm-type glow discharge for controlling the degree of crystallinity in brass alloy thin films

Sputter-deposition rates in different gas directions were used for growing brass thin films in the modified Grimm-type direct current glow discharge. The sputtering and deposition rates were significantly improved by changing the direction of the argon gas flow. The degree of crystallinity and the nanoparticle size of the deposited thin films could also be controlled. Optimal operating conditions such as the gas pressure, applied power, deposition time, and distance from the substrate to the target surface were employed. The degree of crystallinity of the films was determined via the X-ray diffraction technique. Sequence changes in the brass thin film structure to nanocrystalline phases were obtained based on the direction of the Ar gas. However, in all cases, the obtained nanocrystalline films had polycrystalline or single crystalline structure with the normal and the new proposed gas flow direction respectively. Wavelength dispersive X-ray fluorescence analysis confirmed that the films had the same elemental compositions as that of the cathode material. Semi-amorphous and polycrystalline brass thin films were also easily obtained using the normal gas direction. Moreover, the new proposed gas direction in the modified Grimm-type glow discharge resulted in the successful deposition of single crystal thin films with controlled nanoparticle sizes. (C) 2015 Elsevier Ltd. All rights reserved.