Spatial and temporal measurements using polyoxometalate, enzymatic and biofilm layers on a CMOS 0.35 μm 64 X 64-pixel I.S.F.E.T. array sensor

Streklas, Angelos (2016) Spatial and temporal measurements using polyoxometalate, enzymatic and biofilm layers on a CMOS 0.35 μm 64 X 64-pixel I.S.F.E.T. array sensor. PhD thesis, University of Glasgow.

Abstract

This thesis presents the achievements and scientific work conducted using a previously designed and fabricated 64 x 64-pixel ion camera with the use of a 0.35 μm CMOS technology. We used an array of Ion Sensitive Field Effect Transistors (ISFETs) to monitor and measure chemical and biochemical reactions in real time. The area of our observation was a 4.2 x 4.3 mm silicon chip while the actual ISFET array covered an area of 715.8 x 715.8 μm consisting of 4096 ISFET pixels in total with a 1 μm separation space among them. The ion sensitive layer, the locus where all reactions took place was a silicon nitride layer, the final top layer of the austriamicrosystems 0.35 μm CMOS technology used. Our final measurements presented an average sensitivity of 30 mV/pH. With the addition of extra layers we were able to monitor a 65 mV voltage difference during our experiments with glucose and hexokinase, whereas a difference of 85 mV was detected for a similar glucose reaction mentioned in literature, and a 55 mV voltage difference while performing photosynthesis experiments with a biofilm made from cyanobacteria, whereas a voltage difference of 33.7 mV was detected as presented in literature for a similar cyanobacterial species using voltamemtric methods for detection.
To monitor our experiments PXIe-6358 measurement cards were used and measurements were controlled by LabVIEW software. The chip was packaged and encapsulated using a PGA-100 chip carrier and a two-component commercial epoxy. Printed circuit board (PCB) has also been previously designed to provide interface between the chip and the measurement cards.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: sensor, ISFET, biomedical engineering, CMOS, array, polyoxometalate, enzyme, enzymatic glucose, glycolysis, ion, camera monitoring, bacteria, cyanobacteria biofuel.
• Subjects: T Technology > TK Electrical engineering. Electronics Nuclear engineering
• Colleges/Schools: College of Science and Engineering > School of Engineering > Biomedical Engineering; College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Funder's Name: Engineering & Physical Sciences Research Council (EPSRC)
• Supervisor's Name: Cumming, Professor David R.S.
• Date of Award: 2016
• Depositing User: Mr Angelos Streklas
• Unique ID: glathesis:2016-7468
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 11 Jul 2016 07:54
• Last Modified: 26 Jul 2016 07:46
• URI: https://theses.gla.ac.uk/id/eprint/7468