Design, fabrication and characterization of CMOS ISFET for pH measurements

The Ion Sensitive Field Effect Transistor (ISFET) is a potentiometric pH sensor that is easily adapted to a wide range of chemical, biochemical and biomedical applications. The operation of an ISFET is based on the surface adsorption of charges from the test solution in the solid-electrolyte inte...

Full description

Saved in:

Bibliographic Details
Main Author:	Chin, Seng Fatt
Format:	Thesis
Language:	English
Subjects:	Ion Sensitive Field Effect Transistor (ISFET) Potential Hydrogen (pH) pH sensitivity CMOS ISFET Simulation CMOS technology CMOS
Online Access:	http://dspace.unimap.edu.my:80/xmlui/bitstream/123456789/12919/1/p.%201-24.pdf http://dspace.unimap.edu.my:80/xmlui/bitstream/123456789/12919/2/Full%20Text.pdf
Tags:	Add Tag No Tags, Be the first to tag this record!

id	my-unimap-12919
record_format	uketd_dc
spelling	my-unimap-129192011-07-01T07:14:53Z Design, fabrication and characterization of CMOS ISFET for pH measurements Chin, Seng Fatt The Ion Sensitive Field Effect Transistor (ISFET) is a potentiometric pH sensor that is easily adapted to a wide range of chemical, biochemical and biomedical applications. The operation of an ISFET is based on the surface adsorption of charges from the test solution in the solid-electrolyte interface that is part of the gate of the ISFET. As a result of this process, the threshold voltage of the ISFET is modulated.This thesis describes the design, simulation, fabrication and characterization of ISFET for pH measurement of an aqueous solution. Prior to fabrication, the ISFET is simulated via TCAD TSUPREM4 process and MEDICI device simulator. The ISFET is fabricated in-house in the Micro Fabrication Cleanroom Laboratory (MFCL) at Universiti of Malaysia Perlis (UniMAP) by using CMOS fabrication technology. This goal is achieved due to the compatibility of ISFET and CMOS. Silicon nitride was used as an ion sensitive membrane and it was deposited by using Plasma Enhanced Chemical Vapour Deposition (PECVD) technique. A total of six masks were used in this fabrication to create the CMOS ISFET. The ISFET fabricated is aimed at pH measurement of aqueous solution. In order to obtain an accurate characterization of the ISFET, a semiconductor characterization system (SCS) comprises of a micro probe station and a parameter analyzer was utilized. For the analysis of ISFET in test solution, an Ag/AgCl electrode is used as a reference electrode and three types of standard aqueous pH buffer solutions of pH 4, pH 7 and pH 10 were used during the experiment of ISFET analysis. The sensitivity of the ISFETs measured is 40mV/pH for n-channel ISFET and 30mV/pH for p-channel ISFET. These results demonstrate that the in-house fabricated CMOS ISFET is functional as expected. Universiti Malaysia Perlis 2009 Thesis en http://dspace.unimap.edu.my/123456789/12919 http://dspace.unimap.edu.my:80/xmlui/bitstream/123456789/12919/1/p.%201-24.pdf 1d4271a965b90dc848bde0372c7310a1 http://dspace.unimap.edu.my:80/xmlui/bitstream/123456789/12919/2/Full%20Text.pdf a0763c0eab20c4d93c7471c03259e895 http://dspace.unimap.edu.my:80/xmlui/bitstream/123456789/12919/3/license.txt e40f6d077a27bcb3df76e42862359a22 Ion Sensitive Field Effect Transistor (ISFET) Potential Hydrogen (pH) pH sensitivity CMOS ISFET Simulation CMOS technology CMOS School of Microelectronic Engineering
institution	Universiti Malaysia Perlis
collection	UniMAP Institutional Repository
language	English
topic	Ion Sensitive Field Effect Transistor (ISFET) Potential Hydrogen (pH) pH sensitivity CMOS ISFET Simulation CMOS technology CMOS
spellingShingle	Ion Sensitive Field Effect Transistor (ISFET) Potential Hydrogen (pH) pH sensitivity CMOS ISFET Simulation CMOS technology CMOS Chin, Seng Fatt Design, fabrication and characterization of CMOS ISFET for pH measurements
description	The Ion Sensitive Field Effect Transistor (ISFET) is a potentiometric pH sensor that is easily adapted to a wide range of chemical, biochemical and biomedical applications. The operation of an ISFET is based on the surface adsorption of charges from the test solution in the solid-electrolyte interface that is part of the gate of the ISFET. As a result of this process, the threshold voltage of the ISFET is modulated.This thesis describes the design, simulation, fabrication and characterization of ISFET for pH measurement of an aqueous solution. Prior to fabrication, the ISFET is simulated via TCAD TSUPREM4 process and MEDICI device simulator. The ISFET is fabricated in-house in the Micro Fabrication Cleanroom Laboratory (MFCL) at Universiti of Malaysia Perlis (UniMAP) by using CMOS fabrication technology. This goal is achieved due to the compatibility of ISFET and CMOS. Silicon nitride was used as an ion sensitive membrane and it was deposited by using Plasma Enhanced Chemical Vapour Deposition (PECVD) technique. A total of six masks were used in this fabrication to create the CMOS ISFET. The ISFET fabricated is aimed at pH measurement of aqueous solution. In order to obtain an accurate characterization of the ISFET, a semiconductor characterization system (SCS) comprises of a micro probe station and a parameter analyzer was utilized. For the analysis of ISFET in test solution, an Ag/AgCl electrode is used as a reference electrode and three types of standard aqueous pH buffer solutions of pH 4, pH 7 and pH 10 were used during the experiment of ISFET analysis. The sensitivity of the ISFETs measured is 40mV/pH for n-channel ISFET and 30mV/pH for p-channel ISFET. These results demonstrate that the in-house fabricated CMOS ISFET is functional as expected.
format	Thesis
author	Chin, Seng Fatt
author_facet	Chin, Seng Fatt
author_sort	Chin, Seng Fatt
title	Design, fabrication and characterization of CMOS ISFET for pH measurements
title_short	Design, fabrication and characterization of CMOS ISFET for pH measurements
title_full	Design, fabrication and characterization of CMOS ISFET for pH measurements
title_fullStr	Design, fabrication and characterization of CMOS ISFET for pH measurements
title_full_unstemmed	Design, fabrication and characterization of CMOS ISFET for pH measurements
title_sort	design, fabrication and characterization of cmos isfet for ph measurements
granting_institution	Universiti Malaysia Perlis
granting_department	School of Microelectronic Engineering
url	http://dspace.unimap.edu.my:80/xmlui/bitstream/123456789/12919/1/p.%201-24.pdf http://dspace.unimap.edu.my:80/xmlui/bitstream/123456789/12919/2/Full%20Text.pdf
_version_	1747836766355718144

Design, fabrication and characterization of CMOS ISFET for pH measurements

Similar Items