CMOS-compatible purely capacitive interfaces for high-density in-vivo recording from neural tissue

Sven Schroder, Claudia Cecchetto, Stefan Keil, Mufti Mahmud, Evelin Brose, Ozgu Dogan, Gabriel Bertotti, Dirk Wolanski, Bernd Tillack, Jessica Schneidewind, Hassan Gargouri, Michael Arens, Jürgen Bruns, Bernd Szyszka, Stefano Vassanelli, Roland Thewes

Abstract: CMOS-based neural tissue in-vivo recording chips with a purely capacitive interface are presented with 256 sites resp. 256 recording channels. A 3D post-CMOS ALD-based process allows to provide a highly efficient sensor dielectric and to realize a protective insulation layer for the non-active part of the fabricated devices. A simple interconnect-efficient sensor array topology is used. Electrical characterizations and in-vivo measurements with biological content reveal proper operation of the presented approach.