Back to Search
Start Over
Near-infrared lateral photoresponse in InGaAs/GaAs quantum dots
- Source :
- Semiconductor science and technology, 35 (2020): 55029-1. doi:10.1088/1361-6641/ab7774, info:cnr-pdr/source/autori:Golovynskyi, Sergii; Datsenko, Oleksandr I.; Seravalli, Luca; Trevisi, Giovanna; Frigeri, Paola; Gombia, Enos; Babichuk, Ivan S.; Lin, Danying; Li, Baikui; Qu, Junle/titolo:Near-infrared lateral photoresponse in InGaAs%2FGaAs quantum dots/doi:10.1088%2F1361-6641%2Fab7774/rivista:Semiconductor science and technology (Print)/anno:2020/pagina_da:55029-1/pagina_a:/intervallo_pagine:55029-1/volume:35
- Publication Year :
- 2020
- Publisher :
- IOP Publishing, 2020.
-
Abstract
- Infrared photodetectors with In(Ga)As quantum dot (QD) active element functioning on interband and intersubband transitions are currently actively investigated, however, the vertical sensors were mostly reported. In the current study, a multilayer InGaAs/GaAs QD photodetector structure allowing the lateral photocurrent detection at normal incidence has been prepared depositing top contact. In order to have a comparison, a heterostructure with only a stack of InGaAs/GaAs wetting layers (WL) has been grown. In-depth photoelectrical characterization shows an effective broad-band photodetection related to the interband transitions between quantum-confined levels in QDs ranging from 1.03 to 1.38 eV (0.9-1.2 ?m) that covers much wider infrared range in comparison to that from WLs (1.27-1.38 eV). Photoluminescence spectroscopy confirms the existence of QD transitions, observed as intense QD emission which peaked at 1.12 eV (~1 ?m) redshifted in comparison to the WL structure. The mechanisms of photoconductivity are modelled and discussed, comparing both the structures. We also show that our QD stack has an order lower contribution from defects compared to similar QD structures investigated before. At the same time, our structures demonstrate appropriate device characteristics at room temperature, such as the wide dynamic range from 10 to 10 ?W cm and a high photoresponsivity up to 20 A W at low excitation intensities over 10-10 ?W cm, while at higher excitation intensities the responsivity is reduced, exhibiting a strong spectral dependence. Thereby, our results show that the grown multilayer InGaAs/GaAs QD heterostructure is of relevant interest for application in lateral QD photodetectors.
- Subjects :
- Photocurrent
defect
Photoluminescence
Nanostructure
Materials science
nanostructure
business.industry
Ingaas gaas
Near-infrared spectroscopy
quantum dot
Photodetector
photocurrent
Condensed Matter Physics
Electronic, Optical and Magnetic Materials
InGaAs/GaAs
Quantum dot
Materials Chemistry
Optoelectronics
photoluminescence
photodetector
Electrical and Electronic Engineering
business
Subjects
Details
- ISSN :
- 13616641 and 02681242
- Volume :
- 35
- Database :
- OpenAIRE
- Journal :
- Semiconductor Science and Technology
- Accession number :
- edsair.doi.dedup.....1241e4069c11602e9024b2abccdd248e