Efficiency Enhancement of Thin Film Solar Cells Using Plasmonic Gold Nanoparticles and GaAs Absorber Layers

Abstract

This thesis investigated two novel methods for the enhancement of thin film solar cells. First, plasmonic solar cells were fabricated and the effect of Au nanoparticles on the performance of a-Si:H solar cells was investigated experimentally. Au nanoparticles of 10, 20, 50, 80, 100, 200 and 400 nm were spin coated on ITO before metallization. The results show an increase in the Jsc and efficiency with increasing nanoparticle sizes. The Jsc increases from 9.34 mA/cm2 to 10.1 mA/cm2. In addition, the efficiency increases from 4.28% to 5.01%. Second, the performance of thin film a-Si(n+)/c-GaAs(p)/c-Si(p+) heterojunction solar cell was investigated by TCAD simulation. The effect of minority carrier lifetime (?) and GaAs layer thickness has been studied. For comparison, a-Si/c-Si based solar cell was also simulated. The results show that for lifetimes larger than 1?s, the Voc is 0.8V for GaAs and 0.68V for the c-Si cell. In addition, the Jsc for the GaAs cell is about 1.4mA/cm2 larger than the c-Si cell for the 2 micrometer case and it is independent of ??for both cells. As a result, the efficiency of the 2?m GaAs solar cell is 4% more than the c-Si cell for ?=1?s. The effect of GaAs and c-Si absorber layer thickness is also studied. The difference in Jsc between GaAs and c-Si solar cell is larger for thinner solar cells. This bodes well for thin film GaAs based solar cells.

Date of Award	Jun 2013
Original language	American English
Supervisor	Ammar Nayfeh (Supervisor)