Influence of space charges on the impulse response of InGaAs metal-semiconductor-metal photodetectors

Autor: J. Kuhl, Dieter Bimberg, F. Hieronymi, M. Klingenstein, D. Kuhl, T. Wolf, E.H. Bottcher
Rok vydání: 1992
Předmět:
Zdroj: Journal of Lightwave Technology. 10:753-759
ISSN: 0733-8724
DOI: 10.1109/50.143074
Popis: The impulse response of interdigitated metal-semiconductor-metal photodetectors fabricated on an Fe-doped InGaAs absorbing layer and an Fe-doped InP barrier enhancement layer is investigated. For ultra-short pulse excitation of 150 fs at lambda =620 nm the photoresponse is found to be less than 13 ps FWHM for detectors with 1 mu m finger spacing. Above a certain level of illumination, the peak amplitude increases sublinearly and the relative contribution of the tail to the detector response is appreciably enhanced. The screening of the electric field by photo-generated space charges is responsible for this nonlinearity. For detectors with 5 mu m finger spacing illuminated with 1.3 mu m light pulses (FWHM=33 ps), space charge perturbation of the impulse response manifests itself by a decrease of the FWHM and an increase of the fall time with increasing illumination level. The practical consequences for the performance of MSM detectors in various applications are discussed. >
Databáze: OpenAIRE