Research Guide: Dr Saritha A C
- Solar cells
- Thin films
My research work was on ‘Growth and Characterization of P-type Transparent Semiconducting Oxides for Optoelectronic Applications’. Transparent conducting oxides (TCOs) comprise a special class of materials which exhibit the two antagonistic properties of high visible light transparency and electrical conductivity simultaneously. An exceptional characteristic of these materials is that their electrical properties can be tuned across an extremely wide range such that they can behave as insulators, n/p type semiconductors or even as metals while maintaining the optical transparency. TCO materials with controlled carrier densities are called transparent semiconducting oxides (TSOs). This astonishing combination of conductivity and transparency is usually impracticable in intrinsic stoichiometric wide bandgap oxides; however, it is achieved in TCOs by producing them with a non-stoichiometric composition or by introducing appropriate dopants. These materials are believed to have the ability to overcome the many limitations of the conventional silicon semiconductor, and are expected to open up doors to completely new and exciting areas in semiconductor technology.
Most of the naturally occurring TSOs exhibit n-type electrical conductivity. Although p-type TSOs have already made their way into optoelectronic devices such as LEDs, TTFTs, solar cells etc, they are unable to achieve the performance of their n-type counterparts in terms of charge carrier mobility and/or optical transparency. This has detrimentally affected the device efficiency and the development of advanced devices based on active transparent electronic components. In spite of the considerable research efforts going on for more than a decade, the goal of finding efficient p-TSOs has not yet been fulfilled.Thus, it is of greatest interest and importance to develop p-type TSOs with high hole mobility and transparency to begin the real era of optoelectronic devices.