Improving solar cell efficiency through controlled annealing effects of TiO2 thin films

Abstract

In the scope of this research, the impact of thermal annealing on the electrical and optical characteristics of TiO2 thin films is investigated through empirical analysis. Varied annealing temperatures are applied during the production of TiO2 thin films, and their reflection, transmission, absorption, and crystalline structure attributes are meticulously gauged. Through systematic analysis, the optimal annealing temperature is determined to be 500 °C. Remarkably, TiO2 thin films fabricated under this specific temperature exhibit notably reduced reflection values. Moreover, comprehensive scrutiny extends to encompass both electrical and structural attributes, such as carrier density, resistivity, and crystal size, in addition to optical attributes. In the outcome, it is revealed that TiO2 thin films subjected to annealing at 500 °C exhibit the highest carrier density and the lowest resistivity. X-ray diffraction analyses unveil the anatase phase of TiO2 thin films developed at this temperature. Notably, ascending annealing temperatures correlate with amplified crystal sizes and increased surface roughness. Furthermore, the TiO2 thin films are subsequently integrated into crystalline silicon solar cells via employment of the SCAPS (a Solar Cell Capacitance Simulator) software, culminating in a noteworthy 8% enhancement in solar cell efficiency.