Title :
Optical characterisation of quantum well infra-red detector structures
Author :
Guzman, Armando ; Sánchez-Rojas, J.L. ; Tijero, J.M.G. ; Sánchez, J.J. ; Hernando, J. ; Calleja, E. ; Muñoz, E. ; Vergara, G. ; Montojo, M.T. ; Gomez, Luis J. ; Rodriiguez, P. ; Almazan, R. ; Verdú, M.
Author_Institution :
ETSI Telecommun., Ciudad Univ., Madrid, Spain
fDate :
8/1/1999 12:00:00 AM
Abstract :
Optical characterisation of GaAs-AlGaAs quantum well infra-red photodetector (QWIP) structures by interband photoluminescence (PL) spectroscopy has been performed. The effect on the low temperature PL spectrum of both the doping concentration in the wells and the presence of thin lateral barriers is analysed. In addition to the main peak (e1-hh1), a second peak at lower energy is observed in doped structures and attributed to a donor-to-acceptor transition. The broadening of the e1-hh1 peak when the doping in the wells is increased is interpreted in terms of the bandfilling effect in the wells. An additional broadening appears when thin lateral barriers with higher content are introduced in the structure. Responsivities as high as 0.5 A/W without external coupling mechanisms of the incident light have been measured in samples showing the above-mentioned features in the PL spectra
Keywords :
III-V semiconductors; aluminium compounds; gallium arsenide; infrared detectors; photodetectors; photoluminescence; semiconductor quantum wells; GaAs-AlGaAs quantum well infra-red photodetector; PL spectra; QW IR detector structures; bandfilling effect; donor-to-acceptor transition; doped structures; doping concentration; e1-hh1 peak broadening; external coupling mechanisms; incident light; interband photoluminescence spectroscopy; low temperature PL spectrum; optical characterisation; quantum well infra-red detector structures; responsivities; thin lateral barriers;
Journal_Title :
Optoelectronics, IEE Proceedings -
DOI :
10.1049/ip-opt:19990183
