Tanay Seth

Firing and processing effects on microstructure of fritted silver thick film electrode materials for solar cells

Thick film materials (viz. conductor, resistor, dielectric and solder pastes) have been proved to possesses economical processing and functional advantages over other technologies in high volume and quick turn-around production of hybrid microelectronic circuits. Silver thick films are widely used for the front electrode metallization of silicon solar cells. This paper reports the microstructural, physico-chemical and electrical properties of the fritted silver thick film electrode materials (for silicon solar cells) formulated using different processing conditions, which also included treatment with surfactants.

Growth of CuBiS2 thin films by chemical bath deposition technique from an acidic bath

Abstract CuBiS2 thin films have been deposited on a glass substrate by chemical bath deposition (CBD) technique in an acidic medium. Films are deposited for various concentrations of copper and bismuth. The effect of deposition time and temperature on growth of these films have been studied. To obtain good quality films, the films are grown using a complexing agent. The disodium salt of [EDTA] is used as a complexing agent. The effect of deposition time, temperature and pH on growth of these films are reported. Optical, structural and electrical properties of these films are also reported.

Effect of a focusing electric field on the formation of arc generated carbon nanotubes

An efficient modified arc plasma method, where a focusing electric field is superimposed on the arc electric field, is optimized for the bulk generation of highly pure multi-walled carbon nanotubes (MWNTs). Raman spectroscopy and thermogravimetric measurements have been used to optimize the process. It was found that, at the optimized focusing field configuration, this process can utilize about 85% of the consumed anode material as compared to about 35% in the conventional arc plasma method. The sample prepared at the optimized conditions exhibited negligible D band intensity along with a reduced line width (14cm-1) of the G band in the Raman spectrum. The oxidation temperature of this

Large-scale synthesis of nanopowders by transferred arc thermal plasma

The present work describes the preliminary results on large-scale synthesis and characterisation of copper (Cu) and aluminium nitride (AlN) nano powders by transferred arc thermal plasma technique. The transferred arc was used to vaporise the precursor materials (Cu, Al metal 99.9% pure). Nano particles are formed in the gas phase as a result of homogeneous nucleation. The vapours of Al were allowed to react with NH3 gas for the synthesis of AlN. Rapid quenching using Ar/N2 then produced the desired nano powders. For the generation of Cu nano powders, argon was used as a quench gas. The resultant nano-powders of Cu, AlN were collected under the controlled atmosphere. TEM and AFM results show the particle size ranging between 70 nm and 100 nm. These particles possess exotic applications in defence systems, armour for aircraft and vehicles, aeronautical systems, power electronics, microelectronics etc.

Synthesis of uncapped silver nanoparticles using DC arc plasma technique: effect of change in plasma gas on morphological properties

Uncapped silver nanoparticles were synthesised using hitherto unexplored DC arc thermal plasma technique using Ar, He and mixture of Ar and He as plasma gases. Effect of change in plasma gases on the morphological properties of synthesised nanoparticles has been studied. XRD revealed formation of phase pure cubic silver. TEM study disclosed formation of nanoparticles with size in the range of 20-50 nm and 5-30 nm for silver nanopowders synthesised with He and Ar as plasma gases, respectively while a bimodal size distribution with sizes ranging from ∼20 nm to 150 nm is observed for silver nanopowders synthesised with mixture of He and Ar as plasma gases in 2 : 3 ratio. UV-visible spectroscopy results also support the wide particle size distribution. Demixing effect is presumably responsible for increase in particle size and wide variation in particle size distribution in case of nanoparticles synthesised using mixed gas plasmas.