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InGaAs Diodes for Terahertz Sensing—Effect of Molecular Beam Epitaxy Growth Conditions
InGaAs-based bow-tie diodes for the terahertz (THz) range are found to be well suited for development of compact THz imaging systems. To further optimize design for sensitive and broadband THz detection, one of the major challenges remains: to understand the noise origin, influence of growth conditi...
Autores principales: | , , , , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
MDPI
2018
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6264118/ https://www.ncbi.nlm.nih.gov/pubmed/30400312 http://dx.doi.org/10.3390/s18113760 |
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author | Palenskis, Vilius Minkevičius, Linas Matukas, Jonas Jokubauskis, Domas Pralgauskaitė, Sandra Seliuta, Dalius Čechavičius, Bronislovas Butkutė, Renata Valušis, Gintaras |
author_facet | Palenskis, Vilius Minkevičius, Linas Matukas, Jonas Jokubauskis, Domas Pralgauskaitė, Sandra Seliuta, Dalius Čechavičius, Bronislovas Butkutė, Renata Valušis, Gintaras |
author_sort | Palenskis, Vilius |
collection | PubMed |
description | InGaAs-based bow-tie diodes for the terahertz (THz) range are found to be well suited for development of compact THz imaging systems. To further optimize design for sensitive and broadband THz detection, one of the major challenges remains: to understand the noise origin, influence of growth conditions and role of defects for device operation. We present a detailed study of photoreflectance, low-frequency noise characteristics and THz sensitivity of InGaAs bow-tie diodes. The diodes are fabricated from InGaAs wafers grown by molecular beam epitaxy (MBE) on semi-insulating InP substrate under different technological conditions. Photoreflectance spectra indicated the presence of strong built-in electric fields reaching up to 49 kV/cm. It was demonstrated that the spectral density of voltage fluctuations at room temperature was found to be proportional to 1/f, while at lower temperatures, 77–200 K, Lorentzian-type spectra dominate due to random telegraph signals caused by individual capture defects. Furthermore, varying bias voltage, we considered optimal conditions for device room temperature operation in the THz range with respect to signal-to-noise ratio. The THz detectors grown with beam equivalent pressure In/Ga ratio equal to 2.04 exhibit the minimal level of the low-frequency noise, while InGaAs layers grown with beam equivalent pressure In/Ga ratio equal to 2.06 are found to be well suited for fabrication of room temperature bow-tie THz detectors enabling sensitivity of 13 V/W and noise equivalent power (NEP) of 200 pW/√Hz at 0.6 THz due to strong built-in electric field effects. |
format | Online Article Text |
id | pubmed-6264118 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2018 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-62641182018-12-12 InGaAs Diodes for Terahertz Sensing—Effect of Molecular Beam Epitaxy Growth Conditions Palenskis, Vilius Minkevičius, Linas Matukas, Jonas Jokubauskis, Domas Pralgauskaitė, Sandra Seliuta, Dalius Čechavičius, Bronislovas Butkutė, Renata Valušis, Gintaras Sensors (Basel) Article InGaAs-based bow-tie diodes for the terahertz (THz) range are found to be well suited for development of compact THz imaging systems. To further optimize design for sensitive and broadband THz detection, one of the major challenges remains: to understand the noise origin, influence of growth conditions and role of defects for device operation. We present a detailed study of photoreflectance, low-frequency noise characteristics and THz sensitivity of InGaAs bow-tie diodes. The diodes are fabricated from InGaAs wafers grown by molecular beam epitaxy (MBE) on semi-insulating InP substrate under different technological conditions. Photoreflectance spectra indicated the presence of strong built-in electric fields reaching up to 49 kV/cm. It was demonstrated that the spectral density of voltage fluctuations at room temperature was found to be proportional to 1/f, while at lower temperatures, 77–200 K, Lorentzian-type spectra dominate due to random telegraph signals caused by individual capture defects. Furthermore, varying bias voltage, we considered optimal conditions for device room temperature operation in the THz range with respect to signal-to-noise ratio. The THz detectors grown with beam equivalent pressure In/Ga ratio equal to 2.04 exhibit the minimal level of the low-frequency noise, while InGaAs layers grown with beam equivalent pressure In/Ga ratio equal to 2.06 are found to be well suited for fabrication of room temperature bow-tie THz detectors enabling sensitivity of 13 V/W and noise equivalent power (NEP) of 200 pW/√Hz at 0.6 THz due to strong built-in electric field effects. MDPI 2018-11-03 /pmc/articles/PMC6264118/ /pubmed/30400312 http://dx.doi.org/10.3390/s18113760 Text en © 2018 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article Palenskis, Vilius Minkevičius, Linas Matukas, Jonas Jokubauskis, Domas Pralgauskaitė, Sandra Seliuta, Dalius Čechavičius, Bronislovas Butkutė, Renata Valušis, Gintaras InGaAs Diodes for Terahertz Sensing—Effect of Molecular Beam Epitaxy Growth Conditions |
title | InGaAs Diodes for Terahertz Sensing—Effect of Molecular Beam Epitaxy Growth Conditions |
title_full | InGaAs Diodes for Terahertz Sensing—Effect of Molecular Beam Epitaxy Growth Conditions |
title_fullStr | InGaAs Diodes for Terahertz Sensing—Effect of Molecular Beam Epitaxy Growth Conditions |
title_full_unstemmed | InGaAs Diodes for Terahertz Sensing—Effect of Molecular Beam Epitaxy Growth Conditions |
title_short | InGaAs Diodes for Terahertz Sensing—Effect of Molecular Beam Epitaxy Growth Conditions |
title_sort | ingaas diodes for terahertz sensing—effect of molecular beam epitaxy growth conditions |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6264118/ https://www.ncbi.nlm.nih.gov/pubmed/30400312 http://dx.doi.org/10.3390/s18113760 |
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