Use of Bowtie-shaped Nanoapertures and Spherical Plasmonic Metal Nanoparticles to Improve the Opto-electronic Performance of Thin-film Solar Cells

Abstract

This computational study investigates the response of a thin-film solar cell to the use of plasmonic metal nanoparticles of three different combinations embedded within bowtie-shaped nanoapertures etched on the surface of an absorbing Si layer. A pair of spherical metal nanoparticles were placed inside the “empty” volume of the each arm of a bowtie-shaped nanoaperture. The first configuration was formed by placing a pair of silver spherical nanoparticles inside the arms of the bowtie-shaped nanopaerture, the second configuration was formed by similarly placing a pair of aluminum spherical nanoparticles and the third configuration was formed by placing a pair of gold spherical nanoparticles, respectively. The study continued by progressively merging each of the arms of the bowtie-shaped nanoaperture into one another and thereby decreasing the center to center inter-particle distance of the embedded metal nanoparticles. The optoelectronic responses of thin-film Si solar cells due to the effect produced by these nanostructure/nanoparticle combinations were compared to a Si substrate without any such nanoapertures/nanoparticles. The results show significantly increased light absorbed, short-circuit current generated and open-circuit voltage by the Si substrate which is modified with the bowtie-shaped nanoaperture and the metallic nanoparticles when compared to bare Si substrate and nanoaperture alone.