Dry electrode for the measurement of biopotential signals

This paper introduces a kind of silicon-based dry electrode for measuring biological signals. It uses microneedle arrays to penetrate into the stratum corneum to reduce skin impedance. The dry electrode requires neither skin preparation nor the electrolytic gel, is easy to use and causes no skin allergy. Two different technologies are chosen to manufacture microneedle arrays of dry electrode. One is deep dry etching combined with isotropic wet etching. The other is mechanical dicing combined with chemical wet etching (including isotropic wet etching and anisotropic wet etching). Microneedle arrays are coated with metal and divided into 25 mm2 as dry electrode patch. Impedance testing shows that the impedance value of dry electrode can be comparable with that of commercial electrode in the 20 Hz-10 kHz frequency range. The steady-state visual evoked potential recording and analysis prove that the dry electrode can be used to detect electroencephalography.

[1]  Xiaorong Gao,et al.  Design and implementation of a brain-computer interface with high transfer rates , 2002, IEEE Transactions on Biomedical Engineering.

[2]  Burhanuddin Yeop Majlis,et al.  Process Characterization of Wet Etching for High Aspect Ratio Microneedles Development , 2009 .

[3]  K. Park,et al.  Flexible polymeric dry electrodes for the long-term monitoring of ECG , 2008 .

[4]  Swaminathan Rajaraman,et al.  A unique fabrication approach for microneedles using coherent porous silicon technology , 2005 .

[5]  Sang Jun Moon,et al.  Fabrication of microneedle array using LIGA and hot embossing process , 2005 .

[6]  C. Meinhart,et al.  Bulk Micromachined Titanium Microneedles , 2007, Journal of Microelectromechanical Systems.

[7]  Jung-Hwan Park,et al.  Tapered Conical Polymer Microneedles Fabricated Using an Integrated Lens Technique for Transdermal Drug Delivery , 2007, IEEE Transactions on Biomedical Engineering.

[8]  K. Horch,et al.  A silicon-based, three-dimensional neural interface: manufacturing processes for an intracortical electrode array , 1991, IEEE Transactions on Biomedical Engineering.

[9]  Peter Enoksson,et al.  Micromachined electrodes for biopotential measurements , 2001 .

[10]  S. D. Collins,et al.  Microneedle array for transdermal biological fluid extraction and in situ analysis , 2004 .

[11]  Seong Ho Kang,et al.  Improvement in antigen-delivery using fabrication of a grooves-embedded microneedle array , 2009 .

[12]  Giulio Ruffini,et al.  A dry electrophysiology electrode using CNT arrays , 2005, physics/0510145.

[13]  E. Snidero,et al.  Micropatterned dry electrodes for brain-computer interface , 2007 .

[14]  A. Morrissey,et al.  Silicon microneedle formation using modified mask designs based on convex corner undercut , 2007 .

[15]  Göran Stemme,et al.  Characterization of micromachined spiked biopotential electrodes , 2002, IEEE Transactions on Biomedical Engineering.

[16]  M. Allen,et al.  Micromachined needles for the transdermal delivery of drugs , 1998, Proceedings MEMS 98. IEEE. Eleventh Annual International Workshop on Micro Electro Mechanical Systems. An Investigation of Micro Structures, Sensors, Actuators, Machines and Systems (Cat. No.98CH36176.

[17]  Drago Resnik,et al.  Different aspect ratio pyramidal tips obtained by wet etching of (100) and (111) silicon , 2003, Microelectron. J..

[18]  Seiji Aoyagi,et al.  Laser fabrication of high aspect ratio thin holes on biodegradable polymer and its application to a microneedle , 2007 .

[19]  N. Wilke,et al.  Process optimization and characterization of silicon microneedles fabricated by wet etch technology , 2005, Microelectron. J..

[20]  A. B. Frazier,et al.  Characterization of surface micromachined metallic microneedles , 2003 .

[21]  C. Hibert,et al.  Silicon microneedle electrode array with temperature monitoring for electroporation , 2005 .

[22]  Martin Feneberg,et al.  Regular silicon pillars and dichroic filters produced via particle-imprinted membranes , 2007 .

[23]  Mitsuhiro Shikida,et al.  Fabrication of a hollow needle structure by dicing, wet etching and metal deposition , 2006 .

[24]  Francis E. H. Tay,et al.  A microfabricated electrode with hollow microneedles for ECG measurement , 2009 .