Improvement of Below-Bandgap Photoabsorption in GaAs Solar Cells using GaAs/GaNAs/InGaAs Quantum Wells

摘要

We have fabricated GaAs/GaNAs and GaAs/GaNAs/InGaAs multi-quantum wells (MQWs) introduced into the intrinsic region of GaAs p-i-n solar cells by atomic H-assisted RF-molecular beam epitaxy. Compared to the more conventional GaAs/InGaAs-based MQW solar cells, GaAs/GaNAs/InGaAs MQW solar cells can exhibit improved photoresponse in the below-bandgap energy region of GaAs for 870 nm. This is attributed to the extension of band edge into longer wavelengths as achieved by use of GaNAs-based dilute nitride materials