Open AccessOptimal Dark Current Reduction in Quantum Well 9 µm GaAs/AlGaAs Infrared Photodetectors with Improved Detectivity
Author(s) -
Shahram Mohammad Nejad,
Saeed Olyaee,
Maryam Pourmahyabadi
Publication year - 2008
Publication title -
american journal of applied sciences
Language(s) - English
Resource type - Journals
eISSN - 1554-3641
pISSN - 1546-9239
DOI - 10.3844/ajassp.2008.1071.1078
Subject(s) - dark current , responsivity , photodetector , optoelectronics , specific detectivity , current (fluid) , detector , materials science , infrared , current density , noise (video) , infrared detector , reduction (mathematics) , optics , physics , electrical engineering , computer science , mathematics , engineering , geometry , quantum mechanics , artificial intelligence , image (mathematics)
In this research, an optimization approach is presented to decrease the dark current in GaAs/AlGaAs QWIPs. The dark current noise is reduced by increasing Al density in barriers, decreasing detector dimensions and increasing the periodic length of the structure. In addition, increasing the number of periods can reduce both the dark current and responsivity. Therefore, devices can be optimally designed through judicious choice of these parameters. An optimal photodetector structure is designed and simulated to achieve low dark current (11nA) and detectivity of 1.4×1012cm(Hz)1/2/W which is an order of magnitude greater than the present values