Materials Engineering

Project 2:
Integrated Microsensor Devices and Systems for Industrial, Environmental, and Biomedical Applications

Description

This project focuses on the developing advanced micro/nano-technology fabrication techniques and applying micromechanical systems (MEMS) and nanotechnology for creating novel microdevices and integrated microsensors. The research: (i) develops advanced micro/nano-technology processing techniques appropriate for the fabrication of novel MEMS-based sensors and devices; (ii) uses and refines advanced techniques such as micro-milling/drilling, micro-embossing, micro-molding, electroplating, micro-stamping, micro-lamination, wafer-level bonding, etchstop diffusion, and carbon nanotube growth; (iii) designs and fabricates specific MEMS-based sensors and devices having significant DOE-related interests; (iv) strives to fabricate lab-on-a-chip devices for analyte separation and detection, microhotplates for gas sensing, microarrays for retinal stimulation, microtacks for tissue attachment, and carbon nanotube devices for MEMS and electronic applications; (iv) creates advanced packaging techniques, eg stud bump bonding for flip chip technology, and custom electronic platforms for wireless telemetric sensing; (vi) educates and trains students in new device fabrication and application; (vii) establishes and nurtures collaborative research efforts with DOE national laboratories; and (viii) leverages DOE EPSCoR funding with other external research awards.

Contacts

Dr. Kevin M. Walsh (PI)
Department of Electrical and Computer Engineering
University of Louisville
Louisville, KY 40292
Tel: 502-852-0826
Fax: 502-852-1577
Email: walsh@louisville.edu

Dr. Robert S. Keynton (Co-PI)
Department of Mechanical Engineering
University of Louisville
Louisville, KY 40292
Tel: 502-852-6356
Email: r0keyn01@gwise.louisville.edu

Dr. Richard P. Baldwin (Co-PI)
Department of Chemistry
University of Louisville
Louisville, KY 40292
Tel: 502-852-5892
Email: rpbald01@gwise.louisville.edu

Dr. John F. Naber (Co-PI)
Department of Electrical and Computer Engineering
University of Louisville
Louisville, KY 40292
Tel: 502-852-7910
Email: jfnabe01@gwise.louisville.edu

Dr. Bruce W. Alphenaar (Co-PI)
Department of Electrical and Computer Engineering,
University of Louisville
Louisville, KY 40292
Tel: 502-852-1554
Email: bwalph01@gwise.louisville.edu

Dr. Mark. M. Crain (Co-PI)
Department of Electrical and Computer Engineering
University of Louisville
Louisville, KY 40292
Tel: 502-852-1572
Email: mmcrai01@gwise.louisville.edu

Highlight 1

Integrated Capillary Electrophoresis Lab-on-a-Chip Micro-systems for DOE Field Applications
Lab-on-a-chip devices, which are only a small fraction of the size of their conventional bench-top analogs, offer advantages ranging from lower construction cost, decreased sample and reagent consumption, and faster analyses and higher throughput. Lab-on-a-chip platforms consist of 2"x 2" glass chips that contain microfabricated channels and electrodes that allow electrophoretic separation and electrochemical detection to be carried out on a broad range of samples. With its portable battery-powered control and electronics package that have been developed at the University of Louisville, the total weight of a fully suitable chemical detection system for remote or field operations is less than 1 pound.

Lab-on-a-chip micro-system constructed using innovative microfabrication technologies at the University of Louisville under DOE EPSCoR funding.

Highlight 2

Fabrication of Artificial Retinas
Researchers at the University of Louisville have teamed with colleagues from Harvard University, the Massachusetts Institute of Technology and Cornell University to develop a retinal prosthesis. This device targets blind patients with damaged rods and cones as a result of AMD (age-related macular degeneration) or hereditary retinal degeneration. The final prototype consists of an external miniature camera mounted on an eyeglass frame that communicates wirelessly to a custom retinal implant device composed of a flexible micro-electrode stimulation array and custom microelectronics. RF energy is used to remotely power the implanted chip and provide data communication. Attachment of the polyimide micro-array to the retinal tissue is accomplished with tiny micro-tacks micromachined from silicon using DRIE (deep reactive ion etching) or titanium using ultra-precision micromilling techniques. The micro-electrode array and micro-tacks are shown in the figures below. Both represent significant advances in material processing and microfabrication technology.

Flexible micro-electrode retinal stimulation array fabricated using thin spun-on polyimide layers and sputtered conductive films.

Silicon and titanium microtacks (700 um in length) fabricated using deep reactive ion etching and ultra-precision micromilling, respectively, used for retinal tissue attachment.

Recent Publications

1. Jackson, D., Naber, J., Roussel, Jr., T.J., Crain, M.M., Walsh, K.M., Keynton, R.S., and Baldwin, R.P., Portable High Voltage Power Supply and Electrochemical Detection Circuits for Microchip Capillary Electrophoresis, Submitted 10/21/02, Analytical Chemistry, in press.
2. Baldwin, R., Roussel, T.J., Crain, M.M., Bathlagunda, V., Jackson, D.J., Gullapalli, J., Conklin, J.A., Pai, R., Naber, J.F., Walsh, K.M., and Keynton, R.S., Fully-Integrated On-Chip Electrochemical Detection for Capillary Electrophoresis in a Microfabricated Device, Analytical Chemistry, vol. 74, no. 15, pp. 3690-3697, 2002.
3. Li, J., Friedrich, C.R., Keynton, R.S. Design and Fabrication of a Miniaturized, Integrated, High Frequency Acoustical Lens-Transducer System, Institute of Physics: Journal of Micromechanics & Microengineering, vol. 12, no. 3, pp. 219-228, 2002 (Featured Paper).
4. Li, J., Friedrich, C.R., Keynton, R.S., Performance Evaluation of an Integrated, High Frequency Acoustical Lens-Transducer System, IEEE Trans. Ultra., Ferroelec., and Freq. Control, Accepted.
5. K. Tsukagoshi, N. Yoneya, S. Uryu, Y. Aoyagi, A. Kanda, Y. Ootuka, and B. Alphenaar, Carbon nanotube devices for nanoelectronics, Physica B-Condensed Matter, 323, 107 (2002).
6. S. Amakawa, K. Tsukagoshi, K. Nakazato, H. Mizuta, and B. Alphenaar, Single-electron logic based on multiple-tunnel junctions, Vacuum Science and Technology B, (in press, 2003).
7. S. Chakraborty, K. Walsh, B. Alphenaar, Lei Liu, and K. Tsukagoshi, Temperature mediated switching of magnetoresistance in Co-contacted multi-wall carbon nanotubes, Applied Physics Letters, (submitted, 2003).
8. J. Gerbi, O. Auciello, J. Birrell, D. Gruen, J. Carlisle, and B. Alphenaar, Electrical Contacts to Ultrananocrystalline Diamond, Applied Physics Letters, (submitted, 2003).
9. R.C. Mani, S. Sharma, M.K. Sunkara, J. Gullapalli, R. Rao, A.M. Rao, J.M. Cowley, and R.P. Baldwin, Synthesis and Electrochemical Characterization of a Nanocomposite Diamond Electrode, Electrochemical and Solid State Letters, 5, E32-E35 (2002).
10. A. Ciucu, C. Negulescu, and R.P. Baldwin, Detection of Pesticides Using an Amperometric Biosensor Based on a Ferrophthalocyanine Chemically Modified Electrode and an Immobilized Bienzymatic System, Biosensors and Bioelectronics, 18, 303-310 (2003).

Book Chapters

1. B. Alphenaar, S. Chakraborty, and K. Tsukagoshi, Carbon nanotubes for nanoscale spin-electronics, in Electron Transport in Quantum Dots, J. Bird, Ed. (Kluwer Academic / Plenum Publishers, New York, 2003).
2. R. Baldwin, Electrochemical Detection of Carbohydrates at Constant Potential After HPLC and CE Separations, Invited Chapter, in "Carbohydrate Analysis", ed. Z. El Rassi, Journal of Chromatography Library, 66, Elsevier, Amsterdam, 947-959 (2002).

On-Line Publications

1. Baldwin, R., Roussel, T.J., Crain, M.M., Bathlagunda, V., Jackson, D.J., Gullapalli, J., Conklin, J.A., Pai, R., Naber, J.F., Walsh, K.M., and Keynton, R.S., Integrated Electrochemical Detection for Lab on a Chip Analytical Microsystems, WatchIt.com, white paper, 2002.

Patents and Disclosures

1. D.J. Jackson, T.J. Roussel, Jr., M.M. Crain, R.P. Baldwin, R.S. Keynton, J.F. Naber, and K.M. Walsh, Interface Circuit for Capillary Electrophoresis Microchip Devices, Patent Disclosure submitted 2/08/02.
2. D.J. Jackson, T.J. Roussel, Jr., M.M. Crain, R.P. Baldwin, R.S. Keynton, J.F. Naber, and K.M. Walsh, An Improved Geometry for Capillary Electrophoresis Microchip Devices, Patent Disclosure submitted 2/08/02.
3. D.J. Jackson, T.J. Roussel, Jr., M.M. Crain, R.P. Baldwin, R.S. Keynton, J.F. Naber, and K.M. Walsh, Miniature Battery Powered High Voltage Power Supply for Capillary Electrophoresis, Patent Disclosure submitted 2/08/02.
4. D.J. Jackson, T.J. Roussel, Jr., M.M. Crain, R.P. Baldwin, R.S. Keynton, J.F. Naber, and K.M. Walsh, Amperometric Electrochemical Detection Circuit, Patent Disclosure submitted 2/08/02.
5. M.M. Crain, K.M. Walsh, T.J. Roussel, Jr., D.J. Jackson, R.P. Baldwin, R.S. Keynton, J.F. Naber, and J.G. Edelen, A Fully Integrated Microfabricated Capillary Electrophoresis Device with "On-Chip" Electrochemical Detection, Patent Disclosure submitted 2/08/02.
6. J.F.Naber and B.Hnat, A Real Time Monitoring System for Spinal Fusion Surgery, Provisional Patent filed: 8-15-02.

Recognition

• R. Keynton's acoustical lens transducer research was highlighted in The Institute of Physics, Journal of Micromechanics and Microengineering. As a result, it received national and international media attention and was featured on BBC News Online Health, the South African radio program "Future Watch," and 8 trade magazines including: Biophotonics International, Clinica, Medical Tribune, RAD, RT Image, Small Times, Surgical Rounds, and The Engineer.
• J. Naber was elected one of 25 Young Louisvillians to Watch, in Louisville Magazine, 2003.
• R. Keynton, Oak Ridge Associated Universities Ralph E. Powe Award, 2002. Review panel.
• R. Baldwin, Editor, Analytica Chimica Acta, 1/2000-present.

Business Development

• Drs. Naber, Walsh, Keynton, Crain, and Roussel are part of two start-up ventures. One company is called Assenti, LLC and the other is Ortho Data Technologies, LLC. The companies have been established to commercial products of research from the UL. Assenti, LLC was awarded a $500K SBIR from NIH to develop a retinal implantable wireless pressure sensor for the prevention of glaucoma.

Top of Page