Pronounced optical gain attained in Ag/AZO structure for solar cell applications

Recently plasmonic effect has attracted tremendous interests due to its ability of light trapping and improving the photovoltaic performances of solar cells. In this letter, we propose a solution method based fabrication route of Ag plasmons and realize a pronounced optical gain in ZnO:Al (AZO) thin film, which is strongly beneficial to harvest incident sunlight in thin film solar cells. Processing parameters, such as spinning speed, coating times and post-annealing temperature, could be regulated to optimize the plasmon effects of silver particles. The reflectance of silver particles coated AZO (Ag/AZO) is reduced by ~18%, and the transmittance is enhanced by ~40% simultaneously. The underlying mechanisms are discussed in combination with the microstructures of the silver particles.