Reduced radiative currents from GaAs/InGaAs and AlGaAs/GaAs p-i-n quantum well devices

Author

Nelson, J. ; Ballard, I. ; Barnes, J. ; Ekins-Daukes, N. ; Barnham, K.W.J. ; Kluftinger, B.G. ; Tsui, E.S.M. ; Foxon, C.T. ; Cheng, T.S. ; Roberts, J.S.

Author_Institution

Blackett Lab., Imperial Coll. of Sci., Technol. & Med., London, UK

fYear

1997

fDate

29 Sep-3 Oct 1997

Firstpage

919

Lastpage

922

Abstract

Calibrated electroluminescence spectra of GaAs/InGaAs and AlGaAs/GaAs single and double quantum well (QW) p-i-n devices, at various temperatures (200-300 K) and biases (0.8-1.5 V), have been compared to theory to extract the quasi-Fermi level separation, Δφ_f, in the QWs and where possible in the host material. Emission from the host material for the GaAs/InGaAs cell is well fitted with Δφ_f=V_app at all biases and temperatures. In contrast, emission from the QW in both GaAs/InGaAs and AlGaAs/GaAs cases requires a value of Δφ_f which is a few tens of meV less than V_app. We attribute the variations in Δφ_f to irreversible thermally assisted escape from the QWs and detail some preliminary results from double QW samples

Keywords

Fermi level; III-V semiconductors; aluminium compounds; electroluminescence; gallium arsenide; indium compounds; semiconductor quantum wells; solar cells; 0.8 to 1.5 V; 200 to 300 K; AlGaAs-GaAs; AlGaAs/GaAs p-i-n quantum well devices; GaAs-InGaAs; GaAs/InGaAs p-i-n quantum well devices; double quantum well p-i-n devices; host material emission; irreversible thermally assisted escape; quasi-Fermi level separation; reduced radiative currents; single quantum well p-i-n devices; solar cells; Educational institutions; Electroluminescent devices; Gallium arsenide; Indium gallium arsenide; Laboratories; PIN photodiodes; Photovoltaic cells; Radiative recombination; Solid state circuits; Temperature measurement;

fLanguage

English

Publisher

ieee

Conference_Titel

Photovoltaic Specialists Conference, 1997., Conference Record of the Twenty-Sixth IEEE

Conference_Location

Anaheim, CA

ISSN

0160-8371

Print_ISBN

0-7803-3767-0

Type

conf

DOI

10.1109/PVSC.1997.654237

Filename

654237