Computational analysis of thin film InGaAs/GaAs quantum well solar cells with back side light trapping structures

作者：McPheeters Claiborne O^*; Yu Edward T

来源：Optics Express, 2012, 20(23): A864-A878.

DOI：10.1364/OE.20.00A864

Simulations of thin film (similar to 2.5 mu m thick) InGaAs/GaAs quantum well solar cells with various back side reflective and planar, symmetric scattering structures used for light trapping have been performed using rigorous coupled-wave analysis. Two-dimensional periodic metal/dielectric scattering structures were numerically optimized for Airmass 0 photocurrent generation for each device structure. The simulation results indicate that the absorption spectra of devices with both reflective and scattering structures are largely determined by the Fabry-Perot resonance characteristics of the thin film device structure. The scattering structures substantially increase absorption in the quantum wells at wavelengths longer than the GaAs absorption edge through a combination of coupling to modes of the thin film device structures and by reducing parasitic metal absorption compared to planar metal reflectors. For Airmass 0 illumination and 100% carrier collection, the estimated short-circuit current density of devices with In0.3Ga0.7As/GaAs quantum wells improves by up to 4.6 mA/cm(2) (15%) relative to a GaAs homojunction device, with the improvement resulting approximately equally from scattering of light into thin film modes and reduction of metal absorption compared to a planar reflective layer.

• 出版日期2012-11-5