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Title: Characteristics of TiO{sub 2}/ZnO bilayer film towards pH sensitivity prepared by different spin coating deposition process

Abstract

In this study, titanium dioxide (TiO{sub 2}) and zinc oxide (ZnO) bilayer film for pH sensing application will be presented. TiO{sub 2}/ZnO bilayer film with different speed of spin-coating process was deposited on Indium Tin Oxide (ITO), prepared by sol-gel method. This fabricated bilayer film was used as sensing membrane for Extended Gate Field-Effect Transistor (EGFET) for pH sensing application. Experimental results indicated that the sensor is able to detect the sensitivity towards pH buffer solution. In order to obtained the result, sensitivity measurement was done by using the EGFET setup equipment with constant-current (100 µA) and constant-voltage (0.3 V) biasing interfacing circuit. TiO{sub 2}/ZnO bilayer film which the working electrode, act as the pH-sensitive membrane was connected to a commercial metal-oxide semiconductor FET (MOSFET). This MOSFET then was connected to the interfacing circuit. The sensitivity of the TiO2 thin film towards pH buffer solution was measured by dipping the sensing membrane in pH4, pH7 and pH10 buffer solution. These thin films were characterized by using Field Emission Scanning Electron Microscope (FESEM) to obtain the surface morphology of the composite bilayer films. In addition, I-V measurement was done in order to determine the electrical properties of the bilayer films. Accordingmore » to the result obtained in this experiment, bilayer film that spin at 4000 rpm, gave highest sensitivity which is 52.1 mV/pH. Relating the I-V characteristic of the thin films and sensitivity, the sensing membrane with higher conductivity gave better sensitivity.« less

Authors:
;  [1];  [2];  [1];  [3];  [1];  [4]
  1. NANO-Electronic Centre, Faculty of Electrical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor (Malaysia)
  2. Faculty of Electrical Engineering, Universiti Teknologi MARA (UiTM) Shah Alam, 40450 Shah Alam, Selangor (Malaysia)
  3. (NST), Institute of Science (IOS), Faculty of Applied Science, Universiti Teknologi MARA - UiTM, 40450 Shah Alam, Selangor (Malaysia)
  4. (UiTM), 40450 Shah Alam, Selangor (Malaysia)
Publication Date:
OSTI Identifier:
22608609
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; BUFFERS; ELECTRIC CONDUCTIVITY; ELECTRODES; FIELD EMISSION; INDIUM OXIDES; LAYERS; MOSFET; PH VALUE; SCANNING ELECTRON MICROSCOPY; SEMICONDUCTOR MATERIALS; SENSITIVITY; SOL-GEL PROCESS; SPIN-ON COATING; SURFACES; THIN FILMS; TIN OXIDES; TITANIUM; TITANIUM OXIDES; ZINC OXIDES

Citation Formats

Rahman, Rohanieza Abdul, E-mail: rohanieza.abdrahman@gmail.com, Zulkefle, Muhammad Al Hadi, E-mail: alhadizulkefle@gmail.com, Abdullah, Wan Fazlida Hanim, E-mail: wanfaz@salam.uitm.edu.my, Rusop, M., E-mail: rusop@salam.uitm.com, NANO-Science Technology Centre, Herman, Sukreen Hana, E-mail: hana1617@salam.uitm.edu.my, and CoRe of Frontier Materials & Industry Applications, Faculty of Electrical Engineering, Universiti Teknologi MARA. Characteristics of TiO{sub 2}/ZnO bilayer film towards pH sensitivity prepared by different spin coating deposition process. United States: N. p., 2016. Web. doi:10.1063/1.4948877.
Rahman, Rohanieza Abdul, E-mail: rohanieza.abdrahman@gmail.com, Zulkefle, Muhammad Al Hadi, E-mail: alhadizulkefle@gmail.com, Abdullah, Wan Fazlida Hanim, E-mail: wanfaz@salam.uitm.edu.my, Rusop, M., E-mail: rusop@salam.uitm.com, NANO-Science Technology Centre, Herman, Sukreen Hana, E-mail: hana1617@salam.uitm.edu.my, & CoRe of Frontier Materials & Industry Applications, Faculty of Electrical Engineering, Universiti Teknologi MARA. Characteristics of TiO{sub 2}/ZnO bilayer film towards pH sensitivity prepared by different spin coating deposition process. United States. doi:10.1063/1.4948877.
Rahman, Rohanieza Abdul, E-mail: rohanieza.abdrahman@gmail.com, Zulkefle, Muhammad Al Hadi, E-mail: alhadizulkefle@gmail.com, Abdullah, Wan Fazlida Hanim, E-mail: wanfaz@salam.uitm.edu.my, Rusop, M., E-mail: rusop@salam.uitm.com, NANO-Science Technology Centre, Herman, Sukreen Hana, E-mail: hana1617@salam.uitm.edu.my, and CoRe of Frontier Materials & Industry Applications, Faculty of Electrical Engineering, Universiti Teknologi MARA. 2016. "Characteristics of TiO{sub 2}/ZnO bilayer film towards pH sensitivity prepared by different spin coating deposition process". United States. doi:10.1063/1.4948877.
@article{osti_22608609,
title = {Characteristics of TiO{sub 2}/ZnO bilayer film towards pH sensitivity prepared by different spin coating deposition process},
author = {Rahman, Rohanieza Abdul, E-mail: rohanieza.abdrahman@gmail.com and Zulkefle, Muhammad Al Hadi, E-mail: alhadizulkefle@gmail.com and Abdullah, Wan Fazlida Hanim, E-mail: wanfaz@salam.uitm.edu.my and Rusop, M., E-mail: rusop@salam.uitm.com and NANO-Science Technology Centre and Herman, Sukreen Hana, E-mail: hana1617@salam.uitm.edu.my and CoRe of Frontier Materials & Industry Applications, Faculty of Electrical Engineering, Universiti Teknologi MARA},
abstractNote = {In this study, titanium dioxide (TiO{sub 2}) and zinc oxide (ZnO) bilayer film for pH sensing application will be presented. TiO{sub 2}/ZnO bilayer film with different speed of spin-coating process was deposited on Indium Tin Oxide (ITO), prepared by sol-gel method. This fabricated bilayer film was used as sensing membrane for Extended Gate Field-Effect Transistor (EGFET) for pH sensing application. Experimental results indicated that the sensor is able to detect the sensitivity towards pH buffer solution. In order to obtained the result, sensitivity measurement was done by using the EGFET setup equipment with constant-current (100 µA) and constant-voltage (0.3 V) biasing interfacing circuit. TiO{sub 2}/ZnO bilayer film which the working electrode, act as the pH-sensitive membrane was connected to a commercial metal-oxide semiconductor FET (MOSFET). This MOSFET then was connected to the interfacing circuit. The sensitivity of the TiO2 thin film towards pH buffer solution was measured by dipping the sensing membrane in pH4, pH7 and pH10 buffer solution. These thin films were characterized by using Field Emission Scanning Electron Microscope (FESEM) to obtain the surface morphology of the composite bilayer films. In addition, I-V measurement was done in order to determine the electrical properties of the bilayer films. According to the result obtained in this experiment, bilayer film that spin at 4000 rpm, gave highest sensitivity which is 52.1 mV/pH. Relating the I-V characteristic of the thin films and sensitivity, the sensing membrane with higher conductivity gave better sensitivity.},
doi = {10.1063/1.4948877},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1733,
place = {United States},
year = 2016,
month = 7
}
  • High-k TiO{sub 2} thin film on p-type silicon substrate was fabricated by a combined sol-gel and spin coating method. Thus deposited titania film had anatase phase with a small grain size of 16 nm and surface roughness of ≅ 0.6 nm. The oxide capacitance (C{sub ox}), flat band capacitance (C{sub FB}), flat band voltage (V{sub FB}), oxide trapped charge (Q{sub ot}), calculated from the high frequency (1 MHz) C-V curve were 0.47 nF, 0.16 nF, − 0.91 V, 4.7x10{sup −12} C, respectively. As compared to the previous reports, a high dielectric constant of 94 at 1 MHz frequency was observedmore » in the devices investigated here and an equivalent oxide thickness (EOT) was 4.1 nm. Dispersion in accumulation capacitance shows a linear relationship with AC frequencies. Leakage current density was found in acceptable limits (2.1e-5 A/cm{sup 2} for −1 V and 5.7e-7 A/cm{sup 2} for +1 V) for CMOS applications.« less
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