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

Author

Kuhl, Detlef ; Hieronymi, Frank ; Böttcher, E. Holger ; Wolf, Torsten ; Bimberg, Dieter ; Kuhl, Jürgen ; Klingenstein, Markus

Author_Institution

Inst. fuer Festkorperphys. I der Tech. Univ. Berlin, Germany

Volume

10

Issue

6

fYear

1992

fDate

6/1/1992 12:00:00 AM

Firstpage

753

Lastpage

759

Abstract

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 λ=620 nm the photoresponse is found to be less than 13 ps FWHM for detectors with 1 μm 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 μm finger spacing illuminated with 1.3 μm 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

Keywords

III-V semiconductors; gallium arsenide; indium compounds; metal-semiconductor-metal structures; photodetectors; space charge; 13 ps; 150 fs; 620 nm; InGaAs:Fe; InP:Fe; absorbing layer; barrier enhancement layer; detector response; electric field screening; fall time; finger spacing; illumination level; impulse response; interdigitated MSM photodetectors; metal-semiconductor-metal photodetectors; nonlinearity; optical communications equipment; peak amplitude; photoresponse; receivers; semiconductors; space charge perturbation; space charges; ultra-short pulse excitation; Detectors; FETs; Fingers; Indium gallium arsenide; Indium phosphide; Lattices; Lighting; Optical pulses; Photodetectors; Space charge;

fLanguage

English

Journal_Title

Lightwave Technology, Journal of

Publisher

ieee

ISSN

0733-8724

Type

jour

DOI

10.1109/50.143074

Filename

143074