Sensitivity of resonant tunneling diode photodetectors
Abstract
We have studied the sensitivity of AlGaAs/GaAs double barrier resonant tunneling diode photodetectors with an integrated GaInNAs absorption layer for light sensing at the telecommunication wavelength of λ=1.3 µm for illumination powers from pico to micro Watts. The sensitivity decreases nonlinearly with power. An illumination power increase of seven orders of magnitude leads to a reduction of the photocurrent sensitivity from SI =5.82 × 103 A/W to 3.2 A/W. We attribute the nonlinear sensitivity-power dependence to an altered local electrostatic potential due to hole-accumulation that on the one hand tunes the tunneling current, but on the other hand affects the lifetime of photogenerated holes. In particular, the lifetime decreases exponentially with increasing hole-population. The lifetime reduction results from an enhanced electrical field, a rise of the quasi-Fermi level and an increased energy splitting within the triangular potential well. The non-constant sensitivity is a direct result of the non-constant lifetime. Based on these findings, we provide an expression that allows to calculate the sensitivity as a function of illumination power and bias voltage, show a way to model the time-resolved photocurrent, and determine the critical power up to which the resonant tunneling diode photosensor sensitivity can be assumed constant.
Citation
Pfenning , A , Hartmann , F , Langer , F , Kamp , M , Hoefling , S & Worschech , L 2016 , ' Sensitivity of resonant tunneling diode photodetectors ' , Nanotechnology , vol. 27 , no. 35 , 355202 . https://doi.org/10.1088/0957-4484/27/35/355202
Publication
Nanotechnology
Status
Peer reviewed
ISSN
0957-4484Type
Journal article
Description
The authors are grateful for financial support by the BMBF via national project EIPHRIK (FKZ: 13N10710) and the European Union (FPVII (2007-2013) under Grant Agreement No. 318287 LANDAUER).Collections
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