Effect of Sb on GaNAs Intermediate Band Solar Cells

Author

Ahsan, N. ; Miyashita, Naoya ; Islam, Md Minarul ; Kin Man Yu ; Walukiewicz, W. ; Okada, Yoshitaka

Author_Institution

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

Volume

3

Issue

2

fYear

2013

fDate

41365

Firstpage

730

Lastpage

736

Abstract

We present a comparative study on the material properties and two-photon excitation (TPE) experiments that involve three bands between a GaNAs and a GaNAsSb absorber designed for intermediate band solar cells. The absorber layers were sandwiched between p-AlGaAs emitter layers and n-AlGaAs IB barrier layers. This permits production of above the bandgap electron-hole pairs by TPE involving two subband photons with the intermediate band as the stepping stone. A recovery in the carrier population in the intermediate band of the GaNAsSb absorber was realized due to an improved material quality. An enhancement in the photocurrent production due to TPE and an associated improvement in the open-circuit voltage were observed.

Keywords

III-V semiconductors; aluminium compounds; electron-hole recombination; energy gap; gallium arsenide; photoemission; photoexcitation; solar absorber-convertors; solar cells; two-photon spectra; AlGaAs-GaNAs-AlGaAs; AlGaAs-GaNAsSb-AlGaAs; IB barrier layers; bandgap electron-hole pairs; carrier population; emitter layers; intermediate band solar cells; material properties; material quality; open-circuit voltage; photocurrent production; sandwiched absorber layers; subband photons; two-photon excitation; Gallium arsenide; Photoconductivity; Photonics; Photovoltaic cells; Production; Substrates; Temperature measurement; Dilute nitride; intermediate band solar cell (IBSC); molecular beam epitaxy (MBE); two-step photon excitation;

fLanguage

English

Journal_Title

Photovoltaics, IEEE Journal of

Publisher

ieee

ISSN

2156-3381

Type

jour

DOI

10.1109/JPHOTOV.2012.2228296

Filename

6384641