GROWTH OF ZINC OXIDE FOR APPLICATIONS IN SOLAR CELL

Abstract

Zinc oxide is widely under exploration for its application in solar cell as front transparent conducting oxide (TCO) to enhance the efficiency of a solar cell by increasing the light absorption capability. It offers good electrical mobility and conductivity, high transparency; high absorption coefficient, textured surface, better short current density/ increased photocurrent, conversion efficiency and high fill factor competitive to other commercially used TCOs such as Indium doped Tin oxide, SnO2. Along with these improvement factors this abundant material also reduces the cost of fabrication. Theoretical studies have been carried out comprehensively in terms of structure, properties and current state of art fabrication methods for about a century. A variety of techniques e.g Thermal/ plasama/E-Beam evaporation, solution based, sputtering and CVD have been used to fabricate ZnO. Numerous approaches have been employed all over the world to further boost its electrical and optical properties. Doping is often used to enhance the transparency and electrical transport features. ZnO doped with Al, In, Ga, F, H ,Sn, N and Cu has been studied to analyze the effects of dopant on structure, conductivity, mobility, resistance, band gap and optical transmittance. In this work/, ZnO is fabricated based on available local resources to achieve all these improvement factors. This grown layer is then characterized with Xray diffraction , atomic force microscopy, Scanning electron microscopy, Hall effect and spectrophotometry.