Evidence for enhanced carrier escape from multiple stepped quantum well (MSQW) and its impact on photovoltaic performance

Author

Wen, Yu ; Wang, Yunpeng ; Sugiyama, Masakazu ; Nakano, Yoshiaki

Author_Institution

Res. Center for Adv. Sci. & Technol., Univ. of Tokyo, Tokyo, Japan

fYear

2011

fDate

22-26 May 2011

Firstpage

1

Lastpage

3

Abstract

A multiple stepped quantum wells (MSQWs) solar cell, in which GaAs stepped-potential layers are sandwiched between strain-balanced InGaAs wells and GaAsP barriers, has been proposed. The bias-dependent photoluminescence has been studied to estimate the radiative recombination velocity, in comparison between the MSQW and the normal multiple quantum well (MQW) structures. Thermalized energy distribution from the wells was examined in terms of temperature-dependent PL and higher average carrier temperature was observed for MSQWs than for MQWs. Such enhanced carrier escape in the case of MSQWs allowed us to obtain increased short-circuit current density 25 mA/cm² which is approximately 14% higher than that of a normal MQWs solar cell.

Keywords

III-V semiconductors; current density; electron-hole recombination; gallium arsenide; indium compounds; photoluminescence; quantum well devices; sandwich structures; semiconductor quantum wells; solar cells; GaAs stepped-potential layers; GaAsP barriers; InGaAs-GaAs-GaAsP; average carrier temperature; bias-dependent photoluminescence; enhanced carrier escape; multiple stepped quantum well solar cell; normal multiple quantum well structures; photovoltaic performance; radiative recombination velocity; short-circuit current density; strain-balanced InGaAs wells; temperature-dependent PL; thermalized energy distribution; Charge carrier processes; Gallium arsenide; Photovoltaic cells; Quantum dots; Quantum mechanics; Quantum well devices; Temperature measurement;

fLanguage

English

Publisher

ieee

Conference_Titel

Compound Semiconductor Week (CSW/IPRM), 2011 and 23rd International Conference on Indium Phosphide and Related Materials

Conference_Location

Berlin

Print_ISBN

978-1-4577-1753-6

Electronic_ISBN

978-3-8007-3356-9

Type

conf

Filename

5978315