Gateless-FET pH sensor fabricated on undoped AlGaN/GaN HEMT structure HEMT structure

Gateless-FET pH sensor fabricated on undoped AlGaN/GaN HEMT structure HEMT structure

Gallium nitride with wurtzite crystal structure is a chemically stable semiconductor with high internal spontaneous and piezoelectric polarization, which make it highly suitable materials to create very sensitive and robust sensors for the detection of ions, gases and liquids. Sensing characteristic...

Full description

Bibliographic Details
Main Authors: Maneea Eizadi Sharifabad, Mastura Shafinaz Zainal Abidin, Shaharin Fadzli Abd Rahman, Abdul Manaf Hashim, Abdul Rahim Abdul Rahman, Nurul Afzan Omar, Mohd Nizam Osman, Rabia Qindeel
Format: Article
Language:English
Published: Universiti Kebangsaan Malaysia 2011
Online Access:http://journalarticle.ukm.my/708/
http://journalarticle.ukm.my/708/
http://journalarticle.ukm.my/708/1/12_Maneea.pdf
id ukm-708
recordtype eprints
spelling ukm-7082016-12-14T06:27:58Z http://journalarticle.ukm.my/708/ Gateless-FET pH sensor fabricated on undoped AlGaN/GaN HEMT structure HEMT structure Maneea Eizadi Sharifabad, Mastura Shafinaz Zainal Abidin, Shaharin Fadzli Abd Rahman, Abdul Manaf Hashim, Abdul Rahim Abdul Rahman, Nurul Afzan Omar, Mohd Nizam Osman, Rabia Qindeel, Gallium nitride with wurtzite crystal structure is a chemically stable semiconductor with high internal spontaneous and piezoelectric polarization, which make it highly suitable materials to create very sensitive and robust sensors for the detection of ions, gases and liquids. Sensing characteristics of an open-gate liquid-phase sensor fabricated on undoped-AlGaN/GaN high-electron-mobility-transistor (HEMT) structure in aqueous solution was investigated. In ambient atmosphere, the open-gate undoped AlGaN/GaN HEMT clearly showed only the presence of linear region of currents while Si-doped AlGaN/GaN showed the linear and saturation regions of currents, very similar to those of gated devices. This seems to show that very low Fermi level pinning by surface states exists in undoped AlGaN/GaN sample. In aqueous solution, the typical current-voltage (I-V) characteristics of HEMTs with good gate controllability were observed. The potential of the AlGaN surface at the open-gate area is effectively controlled via aqueous solution by Ag/AgCl reference gate electrode. The open-gate undoped AlGaN/GaN HEMT structure is capable of stable operation in aqueous electrolytes and exhibit linear sensitivity, and high sensitivity of 1.9 mA/pH or 3.88 mA/mm/pH at drain-source voltage, VDS = 5 V was obtained. Due to large leakage current where it increases with the negative reference gate voltage, the Nernstian’s like sensitivity cannot be determined. Suppression of current leakage is likely to improve the device performance. The open-gate undoped-AlGaN/GaN structure is expected to be suitable for pH sensing application. Universiti Kebangsaan Malaysia 2011-03 Article PeerReviewed application/pdf en http://journalarticle.ukm.my/708/1/12_Maneea.pdf Maneea Eizadi Sharifabad, and Mastura Shafinaz Zainal Abidin, and Shaharin Fadzli Abd Rahman, and Abdul Manaf Hashim, and Abdul Rahim Abdul Rahman, and Nurul Afzan Omar, and Mohd Nizam Osman, and Rabia Qindeel, (2011) Gateless-FET pH sensor fabricated on undoped AlGaN/GaN HEMT structure HEMT structure. Sains Malaysiana, 40 (3). pp. 267-273. ISSN 0126-6039 http://www.ukm.my/jsm
repository_type Digital Repository
institution_category Local University
institution Universiti Kebangasaan Malaysia
building UKM Institutional Repository
collection Online Access
language English
description Gallium nitride with wurtzite crystal structure is a chemically stable semiconductor with high internal spontaneous and piezoelectric polarization, which make it highly suitable materials to create very sensitive and robust sensors for the detection of ions, gases and liquids. Sensing characteristics of an open-gate liquid-phase sensor fabricated on undoped-AlGaN/GaN high-electron-mobility-transistor (HEMT) structure in aqueous solution was investigated. In ambient atmosphere, the open-gate undoped AlGaN/GaN HEMT clearly showed only the presence of linear region of currents while Si-doped AlGaN/GaN showed the linear and saturation regions of currents, very similar to those of gated devices. This seems to show that very low Fermi level pinning by surface states exists in undoped AlGaN/GaN sample. In aqueous solution, the typical current-voltage (I-V) characteristics of HEMTs with good gate controllability were observed. The potential of the AlGaN surface at the open-gate area is effectively controlled via aqueous solution by Ag/AgCl reference gate electrode. The open-gate undoped AlGaN/GaN HEMT structure is capable of stable operation in aqueous electrolytes and exhibit linear sensitivity, and high sensitivity of 1.9 mA/pH or 3.88 mA/mm/pH at drain-source voltage, VDS = 5 V was obtained. Due to large leakage current where it increases with the negative reference gate voltage, the Nernstian’s like sensitivity cannot be determined. Suppression of current leakage is likely to improve the device performance. The open-gate undoped-AlGaN/GaN structure is expected to be suitable for pH sensing application.
format Article
author Maneea Eizadi Sharifabad,
Mastura Shafinaz Zainal Abidin,
Shaharin Fadzli Abd Rahman,
Abdul Manaf Hashim,
Abdul Rahim Abdul Rahman,
Nurul Afzan Omar,
Mohd Nizam Osman,
Rabia Qindeel,
spellingShingle Maneea Eizadi Sharifabad,
Mastura Shafinaz Zainal Abidin,
Shaharin Fadzli Abd Rahman,
Abdul Manaf Hashim,
Abdul Rahim Abdul Rahman,
Nurul Afzan Omar,
Mohd Nizam Osman,
Rabia Qindeel,
Gateless-FET pH sensor fabricated on undoped AlGaN/GaN HEMT structure HEMT structure
author_facet Maneea Eizadi Sharifabad,
Mastura Shafinaz Zainal Abidin,
Shaharin Fadzli Abd Rahman,
Abdul Manaf Hashim,
Abdul Rahim Abdul Rahman,
Nurul Afzan Omar,
Mohd Nizam Osman,
Rabia Qindeel,
author_sort Maneea Eizadi Sharifabad,
title Gateless-FET pH sensor fabricated on undoped AlGaN/GaN HEMT structure HEMT structure
title_short Gateless-FET pH sensor fabricated on undoped AlGaN/GaN HEMT structure HEMT structure
title_full Gateless-FET pH sensor fabricated on undoped AlGaN/GaN HEMT structure HEMT structure
title_fullStr Gateless-FET pH sensor fabricated on undoped AlGaN/GaN HEMT structure HEMT structure
title_full_unstemmed Gateless-FET pH sensor fabricated on undoped AlGaN/GaN HEMT structure HEMT structure
title_sort gateless-fet ph sensor fabricated on undoped algan/gan hemt structure hemt structure
publisher Universiti Kebangsaan Malaysia
publishDate 2011
url http://journalarticle.ukm.my/708/
http://journalarticle.ukm.my/708/
http://journalarticle.ukm.my/708/1/12_Maneea.pdf
first_indexed 2023-09-18T19:31:34Z
last_indexed 2023-09-18T19:31:34Z
_version_ 1777404995907354624

Similar Items