Title :
Reduced radiative currents from GaAs/InGaAs and AlGaAs/GaAs p-i-n quantum well devices
Author :
Nelson, J. ; Barnes, J. ; Ekins-Daukes, N. ; Barnham, K.W.J. ; Kluftinger, B. ; 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
Abstract :
Calibrated electroluminescence spectra of GaAs/lnGaAs and AlGaAs/GaAs single and double quantum well (QW) p-i-n devices, at various temperatures (200-300 K) and applied biases (Vapp=0.81-1.5 V), have been compared to theory to extract the quasi-Fermi level separation, Δφf, in the QWs and where possible in the host material. Emission from the host material for the GaAs/lnGaAs cell is well fitted with Δφf=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 Δφf which is a few tens of meV less than Vapp. We attribute the variations in Δφf 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; electroluminescent devices; gallium arsenide; indium compounds; quantum well devices; 0.8 to 1.5 V; 200 to 300 K; AlGaAs-GaAs; AlGaAs/GaAs; GaAs-InGaAs; GaAs/InGaAs; applied biases; calibrated electroluminescence spectra; double quantum well; host material; irreversible thermally assisted escape; p-i-n quantum well devices; quasi-Fermi level separation; reduced radiative currents; single quantum well; Charge coupled devices; Electroluminescent devices; Gallium arsenide; Indium gallium arsenide; Laser excitation; PIN photodiodes; Photoconductivity; Photovoltaic cells; Solid state circuits; Temperature measurement;
Conference_Titel :
Compound Semiconductors, 1997 IEEE International Symposium on
Conference_Location :
San Diego, CA
Print_ISBN :
0-7503-0556-8
DOI :
10.1109/ISCS.1998.711674
