Enhancement of current collection in epitaxial lift-off InAs/GaAs quantum dot thin film solar cell and concentrated photovoltaic study

Author

Sogabe, Tomohiro ; Shoji, Yozo ; Mulder, Peter ; Schermer, John ; Tamayo, Efrain ; Okada, Yoshitaka

Author_Institution

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

fYear

2014

fDate

8-13 June 2014

Firstpage

3485

Lastpage

3487

Abstract

We report the fabrication of a thin film InAs/GaAs quantum dot solar cell (QD cell) by applying epitaxial lift-off (ELO) approach to the GaAs substrate. Except the enhanced sub-GaAs bandgap current collection (~0.16mA/cm²) from 900nm and beyond, we confirmed significant current collection enhancement (~0.91mA/cm²) in ELO-InAs QD cell within the wavelength range of 700nm~900nm. We also confirmed the ELO induced resonance cavity effect is able to increase the solar cell efficiency by increasing both the short circuit current and open voltage. The electric field intensity of the resonance cavity formed in the ELO film between the Au back reflector and the GaAs front contact layer was analyzed in detail by finite-differential time-domain (FDTD) simulation. In addition we performed concentrate photovoltaic study and analyzed the effect of intermediates states on the open voltage under varied concentrated light intensity for the ELO-InAs QD cell.

Keywords

gallium arsenide; indium compounds; quantum dots; solar cells; thin film devices; ELO film; FDTD simulation; QD cell; concentrated light intensity; concentrated photovoltaic; current collection enhancement; electric field intensity; epitaxial lift-off approach; finite-differential time-domain simulation; gold back reflector; open voltage; quantum dot thin film solar cell; resonance cavity; short circuit current; solar cell efficiency; Absorption; Finite difference methods; Gallium arsenide; Photovoltaic cells; Photovoltaic systems; Time-domain analysis; Concentrated photovoltaics; ELO; FDTD; Quantum dot Solar cell; Thin film;

fLanguage

English

Publisher

ieee

Conference_Titel

Photovoltaic Specialist Conference (PVSC), 2014 IEEE 40th

Conference_Location

Denver, CO

Type

conf

DOI

10.1109/PVSC.2014.6925682

Filename

6925682