www.ietdl.org Published in IET Nanobiotechnology Received on 28th June 2013 Revised on 3rd September 2013 Accepted on 6th September 2013 doi: 10.1049/iet-nbt.2013.0049
ISSN 1751-8741
Nanoscale electrode arrays produced with microscale lithographic techniques for use in biomedical sensing applications Jonathan G. Terry1, Ilka Schmüser1,2, Ian Underwood1, Damion K. Corrigan2, Neville J. Freeman3, Andrew S. Bunting1, Andrew R. Mount2, Anthony J. Walton1 1
School of Engineering, Institute for Integrated Micro and Nano Systems, The University of Edinburgh, Scottish Microelectronics Centre, The King’s Buildings, Edinburgh EH9 3JF, UK 2 School of Chemistry, The University of Edinburgh, Joseph Black Building, The King’s Buildings, Edinburgh, Scotland EH9 3JJ, UK 3 NanoFlex Ltd, Daresbury Innovation Centre, Keckwick Lane, Daresbury WA4 4FS, UK E-mail: [email protected]
Abstract: A novel technique for the production of nanoscale electrode arrays that uses standard microfabrication processes and micron-scale photolithography is reported here in detail. These microsquare nanoband edge electrode (MNEE) arrays have been fabricated with highly reproducible control of the key array dimensions, including the size and pitch of the individual elements and, most importantly, the width of the nanoband electrodes. The definition of lateral features to nanoscale dimensions typically requires expensive patterning techniques that are complex and low-throughput. However, the fabrication methodology used here relies on the fact that vertical dimensions (i.e. layer thicknesses) have long been manufacturable at the nanoscale using thin film deposition techniques that are well established in mainstream microelectronics. The authors report for the first time two aspects that highlight the particular suitability of these MNEE array systems for probe monolayer biosensing. The first is simulation, which shows the enhanced sensitivity to the redox reaction of the solution redox couple. The second is the enhancement of probe film functionalisation observed for the probe film model molecule, 6-mercapto-1-hexanol compared with microsquare electrodes. Such surface modification for specific probe layer biosensing and detection is of significance for a wide range of biomedical and other sensing and analytical applications.
1
Introduction
1.1 Importance/advantages of nanoelectrode devices and arrays For over quarter of a century, the development of smaller and smaller feature sizes in electrodes for chemical and biomedical sensing has seen critical dimensions shrink from the macro-scale (at least one dimension (1D) on the millimetre scale) to the nanoscale (
ISSN 1751-8741
Nanoscale electrode arrays produced with microscale lithographic techniques for use in biomedical sensing applications Jonathan G. Terry1, Ilka Schmüser1,2, Ian Underwood1, Damion K. Corrigan2, Neville J. Freeman3, Andrew S. Bunting1, Andrew R. Mount2, Anthony J. Walton1 1
School of Engineering, Institute for Integrated Micro and Nano Systems, The University of Edinburgh, Scottish Microelectronics Centre, The King’s Buildings, Edinburgh EH9 3JF, UK 2 School of Chemistry, The University of Edinburgh, Joseph Black Building, The King’s Buildings, Edinburgh, Scotland EH9 3JJ, UK 3 NanoFlex Ltd, Daresbury Innovation Centre, Keckwick Lane, Daresbury WA4 4FS, UK E-mail: [email protected]
Abstract: A novel technique for the production of nanoscale electrode arrays that uses standard microfabrication processes and micron-scale photolithography is reported here in detail. These microsquare nanoband edge electrode (MNEE) arrays have been fabricated with highly reproducible control of the key array dimensions, including the size and pitch of the individual elements and, most importantly, the width of the nanoband electrodes. The definition of lateral features to nanoscale dimensions typically requires expensive patterning techniques that are complex and low-throughput. However, the fabrication methodology used here relies on the fact that vertical dimensions (i.e. layer thicknesses) have long been manufacturable at the nanoscale using thin film deposition techniques that are well established in mainstream microelectronics. The authors report for the first time two aspects that highlight the particular suitability of these MNEE array systems for probe monolayer biosensing. The first is simulation, which shows the enhanced sensitivity to the redox reaction of the solution redox couple. The second is the enhancement of probe film functionalisation observed for the probe film model molecule, 6-mercapto-1-hexanol compared with microsquare electrodes. Such surface modification for specific probe layer biosensing and detection is of significance for a wide range of biomedical and other sensing and analytical applications.
1
Introduction
1.1 Importance/advantages of nanoelectrode devices and arrays For over quarter of a century, the development of smaller and smaller feature sizes in electrodes for chemical and biomedical sensing has seen critical dimensions shrink from the macro-scale (at least one dimension (1D) on the millimetre scale) to the nanoscale (
