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Title: Post-deposition annealing temperature dependence TiO{sub 2}-based EGFET pH sensor sensitivity

Abstract

EGFET pH sensor is one type of pH sensor that is used to measure and determine pH of a solution. The sensing membrane of EGFET pH sensor plays vital role in the overall performance of the sensor. This paper studies the effects of different annealing temperature of the TiO{sub 2} sensing membranes towards sensitivity of EGFET pH sensor. Sol-gel spin coating was chosen as TiO{sub 2} deposition techniques since it is cost-effective and produces thin film with uniform thickness. Deposited TiO{sub 2} thin films were then annealed at different annealing temperatures and then were connected to the gate of MOSFET as a part of the EGFET pH sensor structure. The thin films now act as sensing membranes of the EGFET pH sensor and sensitivity of each sensing membrane towards pH was measured. From the results it was determined that sensing membrane annealed at 300 °C gave the highest sensitivity followed by sample annealed at 400 °C and 500 °C.

Authors:
; ;  [1];  [2];  [3];  [4]
  1. NANO-ElecTronic Centre (NET), Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor (Malaysia)
  2. Faculty of Electrical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor (Malaysia)
  3. NANO-Science Technology (NST), Institute of Science (IOS), Faculty of Applied Sciences, Universiti Teknologi MARA - UiTM, 40450 Shah Alam, Selangor (Malaysia)
  4. Core of Frontier Materials & Industry Applications, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor (Malaysia)
Publication Date:
OSTI Identifier:
22608598
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1733; Journal Issue: 1; Conference: IC-NET 2015: International conference on nano-electronic technology devices and materials 2015, Selangor (Malaysia), 27 Feb - 2 Mar 2015; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANNEALING; MEMBRANES; MOSFET; PH VALUE; SENSITIVITY; SENSORS; SOL-GEL PROCESS; SPIN; SPIN-ON COATING; TEMPERATURE DEPENDENCE; THICKNESS; THIN FILMS; TITANIUM OXIDES

Citation Formats

Zulkefle, M. A., E-mail: alhadizulkefle@gmail.com, Rahman, R. A., E-mail: rohanieza.abdrahman@gmail.com, Yusoff, K. A., E-mail: khairul.aimi.yusof@gmail.com, Abdullah, W. F. H., E-mail: wanfaz@salam.uitm.edu.my, Rusop, M., E-mail: rusop@salam.uitm.edu.my, and Herman, S. H., E-mail: hana1617@salam.uitm.edu.my. Post-deposition annealing temperature dependence TiO{sub 2}-based EGFET pH sensor sensitivity. United States: N. p., 2016. Web. doi:10.1063/1.4948860.
Zulkefle, M. A., E-mail: alhadizulkefle@gmail.com, Rahman, R. A., E-mail: rohanieza.abdrahman@gmail.com, Yusoff, K. A., E-mail: khairul.aimi.yusof@gmail.com, Abdullah, W. F. H., E-mail: wanfaz@salam.uitm.edu.my, Rusop, M., E-mail: rusop@salam.uitm.edu.my, & Herman, S. H., E-mail: hana1617@salam.uitm.edu.my. Post-deposition annealing temperature dependence TiO{sub 2}-based EGFET pH sensor sensitivity. United States. doi:10.1063/1.4948860.
Zulkefle, M. A., E-mail: alhadizulkefle@gmail.com, Rahman, R. A., E-mail: rohanieza.abdrahman@gmail.com, Yusoff, K. A., E-mail: khairul.aimi.yusof@gmail.com, Abdullah, W. F. H., E-mail: wanfaz@salam.uitm.edu.my, Rusop, M., E-mail: rusop@salam.uitm.edu.my, and Herman, S. H., E-mail: hana1617@salam.uitm.edu.my. Wed . "Post-deposition annealing temperature dependence TiO{sub 2}-based EGFET pH sensor sensitivity". United States. doi:10.1063/1.4948860.
@article{osti_22608598,
title = {Post-deposition annealing temperature dependence TiO{sub 2}-based EGFET pH sensor sensitivity},
author = {Zulkefle, M. A., E-mail: alhadizulkefle@gmail.com and Rahman, R. A., E-mail: rohanieza.abdrahman@gmail.com and Yusoff, K. A., E-mail: khairul.aimi.yusof@gmail.com and Abdullah, W. F. H., E-mail: wanfaz@salam.uitm.edu.my and Rusop, M., E-mail: rusop@salam.uitm.edu.my and Herman, S. H., E-mail: hana1617@salam.uitm.edu.my},
abstractNote = {EGFET pH sensor is one type of pH sensor that is used to measure and determine pH of a solution. The sensing membrane of EGFET pH sensor plays vital role in the overall performance of the sensor. This paper studies the effects of different annealing temperature of the TiO{sub 2} sensing membranes towards sensitivity of EGFET pH sensor. Sol-gel spin coating was chosen as TiO{sub 2} deposition techniques since it is cost-effective and produces thin film with uniform thickness. Deposited TiO{sub 2} thin films were then annealed at different annealing temperatures and then were connected to the gate of MOSFET as a part of the EGFET pH sensor structure. The thin films now act as sensing membranes of the EGFET pH sensor and sensitivity of each sensing membrane towards pH was measured. From the results it was determined that sensing membrane annealed at 300 °C gave the highest sensitivity followed by sample annealed at 400 °C and 500 °C.},
doi = {10.1063/1.4948860},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1733,
place = {United States},
year = {Wed Jul 06 00:00:00 EDT 2016},
month = {Wed Jul 06 00:00:00 EDT 2016}
}
  • In order to narrow the band gap of TiO{sub 2}, nitrogen doping by combining thermal atomic layer deposition (TALD) of TiO{sub 2} and plasma enhanced atomic layer deposition (PEALD) of TiN has been implemented. By altering the ratio between TALD TiO{sub 2} and PEALD TiN, the as synthesized TiO{sub x}N{sub y} films showed different band gaps (from 1.91 eV to 3.14 eV). In situ x-ray diffraction characterization showed that the crystallization behavior of these films changed after nitrogen doping. After annealing in helium, nitrogen doped TiO{sub 2} films crystallized into rutile phase while for the samples annealed in air a preferential growthmore » of the anatase TiO{sub 2} along (001) orientation was observed. Photocatalytic tests of the degradation of stearic acid were done to evaluate the effect of N doping on the photocatalytic activity.« less
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  • In this paper, the off-morphotropic-phase-boundary 74(Bi{sub 1/2}Na{sub 1/2})TiO{sub 3}-20.8(Bi{sub 1/2}K{sub 1/2})TiO{sub 3}-5.2BaTiO{sub 3} ceramics were fabricated at different sintering temperatures. It was found out that as the sintering temperature increases, the volatilization of the A-site elements is aggravated, thus generating the oxygen vacancies; meanwhile, the tetragonality of the perovskite lattice reduces gradually. Besides, the temperature-dependent dielectric responses revealed that as the sintering temperature increases, the depolarization temperature T{sub d} decreases while the Curie-Weiss point T{sub C} increases. It is suggested that the lattice distortion, other than the oxygen vacancies, is the crucial factor in influencing the depolarization temperature.
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