Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Ultracompact optrode with integrated laser diode chips and SU-8 waveguides for optogenetic applications

: Schwaerzle, M.; Seidl, K.; Schwarz, U.T.; Paul, O.; Ruther, P.


Institute of Electrical and Electronics Engineers -IEEE-; IEEE Robotics and Automation Society:
IEEE 26th International Conference on Micro Electro Mechanical Systems, MEMS 2013. Vol.2 : Taipei, Taiwan, 20 - 24 January 2013
New York, NY: IEEE, 2013
ISBN: 978-1-4673-5654-1 (Print)
ISBN: 978-1-4673-5655-8
International Conference on Micro Electro Mechanical Systems (MEMS) <26, 2013, Taipei>
Fraunhofer IAF ()

This paper reports on the design, fabrication and characterization of an innovative silicon-based neural probe with optical functionality. This so-called optrode is intended as an ultracompact tool for optogenetic applications in neuroscientific research. Beside platinum microe-lectrodes for electrical recording applications, bare laser diode (LD) chips combined with waveguides (WGs) implemented in the negative photoresist SU-8 are integrated on the probe. The assembly of the bare LD chips applies flip-chip and wire bonding and benefits of a lateral alignment accuracy better ±5 µm required for the efficient coupling of light into the 15-µm-wide and 13-µm-high WGs. Undesired tissue illumination due to stray light is effectively blocked using a micromachined cover chip adhesively bonded to the probe base. Probe shafts with a length of up to 8 mm and a thickness of 50 m carrying four electrodes and two WGs each have been realized. The maximum optical output power per WG was m easured to be 29.7 mW/mm2 for LDs with a center wavelength of 650 nm.