Title :
Quantum tunneling design for ultra-fast photogenerated carrier collection in p-i-n III–V quantum confined solar cells
Author :
Alemu, Andenet ; Freundlich, Alex
Author_Institution :
Photovoltaics and Nanostructures Laboratories, Center for Advanced Materials, University of Houston, Texas 77204-5507, USA
Abstract :
III–V semiconductor based quantum structures displaying quasi-3D holes and resonant tunneling alignment at the conduction band incorporated in the intrinsic region of p-i-n GaAs solar cells are investigated. The choices of the material system and energy band design are tuned towards facilitating the collection of all photo-generated carriers while minimizing recombination losses. Ultra-fast carrier transfer times in the order of 10−15 s are obtained indicating the possibility of extracting carriers before slower recombination losses. The designs are expected to minimize radiative recombination. The faster spatial separation between tunneling electrons and quasi-3D holes under electric field is expected to play a key role in reducing carrier recombination. Such carefully engineered quantum confined material system optimized for improved collection of photo-generated carriers is anticipated to usher efficiencies in the vicinity of ideal limits.
Keywords :
Carrier confinement; Conducting materials; Gallium arsenide; PIN photodiodes; Photovoltaic cells; Potential well; Radiative recombination; Resonant tunneling devices; Semiconductor materials; Spontaneous emission;
Conference_Titel :
Photovoltaic Specialists Conference, 2008. PVSC '08. 33rd IEEE
Conference_Location :
San Diego, CA, USA
Print_ISBN :
978-1-4244-1640-0
Electronic_ISBN :
0160-8371
DOI :
10.1109/PVSC.2008.4922602