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

Journal Article · Wed Jul 06 00:00:00 EDT 2016 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.4948877· OSTI ID:22608609

Rahman, Rohanieza Abdul, E-mail: [e-mail]; Zulkefle, Muhammad Al Hadi, E-mail: [e-mail] ^[1]; Abdullah, Wan Fazlida Hanim, E-mail: [e-mail] ^[2]; Rusop, M., E-mail: [e-mail] ^[1]; NANO-Science Technology Centre ^[3]; Herman, Sukreen Hana, E-mail: [e-mail] ^[1]; CoRe of Frontier Materials & Industry Applications, Faculty of Electrical Engineering, Universiti Teknologi MARA ^[4]

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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)

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.

• OSTI ID: 22608609
• Journal Information: AIP Conference Proceedings, Vol. 1733, 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); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

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