Enhanced absorption in thin film silicon solar cell using plasmonic nanoparticles: An FDTD study

Abstract

Solar energy is a clean and renewable energy source that has the potential to replace fossil fuel with effective con- version of solar energy to electrical power. Research into thin film solar cells has been of priority because of the lower usage of semiconducting material and thereby lower cost. But the thin film solar cells may also result in low device efficiency caused by inefficient absorption. Researchers are still looking for a better design of solar cell for enhanced performance in terms of light trapping and photocurrent. Various methods have been proposed for enhanced light trapping and efficiency. The nanostructured metal particles in solar cells is shown to produce absorption enhancement due to localized surface plasmon. In this context, we per- form a numerical investigation on the broadband light absorption enhancement in thin-film plasmonic solar cell with nanoparticle array over the silicon layer using Finite Difference Time Domain (FDTD) method. The choice of proper metal nanoparticles, size of nanoparticles and interparticle spacing are crucial in the study. Silver and gold are most studied materials due to their surface plasmon resonances located in the visible range. Aluminium is an abundant material whose surface plasmon resonance is located in the UV region. We performed a detailed investigation into the effect of nanoarray of silver, gold and aluminium nanoparticles over the silicon layer of the plasmonic thin film solar cell on the broadband absorption enhancement of the solar cell. The obtained result were compared for ascertaining the choice of material, size and interparticle spacing for optical absorption enhancement.