Title :
A multi-step superlattice solar cell with enhanced subband absorption and open circuit voltage
Author :
Wang, YunPeng ; Sodabanlu, Hassanet ; Ma, ShaoJun ; Fujii, Hirosama ; Watanabe, Kentaroh ; Sugiyama, Masakazu ; Nakano, Yoshiaki
Author_Institution :
Res. Center for Adv. Sci. & Technol., Univ. of Tokyo, Tokyo, Japan
Abstract :
In the report, we propose a multiple stepped superlattice (MS-SL) structure, in which GaAs stepped-potential layers are sandwiched between strain-balanced InGaAs wells and GaAsP barriers, for photovoltaic application. Comparison between the normal SL cell and MS-SL cell indicate that the step design in MS-SL cell enhanced sunband absorption to the host bulk material, while reduced overall recombination loss, exhibited a surprising advantage over SL cell in conversion efficiency. According to experimental results, discussions have been made on the competition process between carrier recombinations and carrier escape kinetics from the wells.
Keywords :
III-V semiconductors; absorption; gallium arsenide; indium compounds; semiconductor quantum wells; semiconductor superlattices; solar cells; GaAsP; InGaAs; MS-SL cell enhanced sunband absorption; MS-SL cell structure; carrier escape kinetics; carrier recombinations; host bulk material; multistep superlattice solar cell; open circuit voltage; photovoltaic application; recombination loss; stepped-potential layers; strain-balanced wells; Absorption; Gallium arsenide; Indexes; Kinetic theory; Transient analysis; carrier lifetime; open circuit voltage; photovoltaic cells; quantum well; strain;
Conference_Titel :
Photovoltaic Specialists Conference (PVSC), 2012 38th IEEE
Conference_Location :
Austin, TX
Print_ISBN :
978-1-4673-0064-3
DOI :
10.1109/PVSC.2012.6317974