FalkBarz.jpg Host Laboratory TAKEUCHI LAB.
Position in LIMMS EUJO-LIMMS Researcher (IMTEK)
Main Research Topic in LIMMS

Advanced-MEMS - Flexible Smart Intracortical Neural Probes


Neural probe, Microelectrodes, Silicon, Polymers, Bioresorbable, Stiffening


Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
Phone:+81 (0)3 5452 6036 / Fax:+81 (0)3 5452 6088


IMTEK - Department of Microsystems Engineering
Microsystem Materials Laboratory (MML), University of Freiburg
Georges-Koehler-Allee 103, 79110 Freiburg, Germany

E-mail falk at iis.u-tokyo.ac.jp
Download icon_pdf.gifAbstract2014_FBarz.pdf


Short resume :
2012-now Actual position
2008-2012 Here
2004-2008 Here
2001-2003 Here

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Research Projects in Limms

1- Flexible Smart Intracortical Neural Probes
Context :
The long-term recording capability of silicon-based (Si-based) intracortical neural probe arrays {Fig.1} is a challenge in neuroscientific research. This limitation is caused by a loss of neural signals and probe encapsulation related to the size and mechanical properties of the probe and the foreign body response. While flexible polymer probes can lower the mechanical mismatch to the cortical tissue and reduce adverse tissue reactions, only CMOS-based silicon devices provide access to high-density microelectrode arrays [1]. This research aims at implementing a Si/polymer-composite neural probe with improved mechanical properties and CMOS microelectronics for intracortical neural recording.
Objectives & Methods :
In this study efficient fabrication and assembly techniques for miniaturized Si-based electrode arrays and polymer interconnects will be developed. Wafer-level fabrication of Parylene-C-based interconnects directly on the electrode array will allow to avoid chip-level flip-chip bonding of the two components [2]. Bioresorbable coatings [3] and miniaturization of the rigid electrode array will provide appropriate mechanical stability during implantation as well as high flexibility in-situ. Appropriate coating materials have to be selected with respect to their mechanical properties and in-vivo applicability. Coating schemes need to be tailored to the miniaturized neural probes.
Results :
Flexible neural probes with a pronounced reduction in footprint have been designed and assembled on the chip-level for coating experiments. A bioresorbable polyethylene glycol (PEG) coating was applied to the probes by molding. The stiffening allowed probe insertion into a Agar-based brain model {Fig.2 (a,b)}. On the wafer-level, the Si-based probe tips have been combined with flexible interconnects in a novel fabrication process {Fig.2 (c)}.


Fig. 1 Optical micrograph of conventional Si-based neural probe assembled on chip-level.


Fig. 2 (a,b) Photographs of insertion experiment, (c) micrograph of flexible neural probe fabricated on a handle wafer.

References :
[1] K. Seidl et al., Proc. IEEE MEMS 2009, pp. 232-235.
[2] S. Kisban et al., Proc. IFMBE 2009, pp. 107-110.
[3] S. Takeuchi et al., Lab on a chip, 5, pp. 519-23, 2005.

Main publication List (papers, conferences and patent)







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