We study the electrical interfacing of semiconductors and of living cells, in particular of neurons. Cellular processes are coupled to microelectronic devices through the direct contact of cell membranes and semiconductor chips. The research is directed (i) to reveal the structure and dynamics of the cell-semiconductor interface and (ii) to build up hybrid neuroelectronic networks.

We explore the new world at the interface of the electronics in inorganic solids and the ionics in living cells. This basic research provides the basis for future applications in medical prosthetics, biosensorics, brain research and neurocomputation.

Developments of new methods is a major task, such as
- fluorescence interferometry to study the geometry of cell adhesion,
- fluorescent voltage-sensitive dyes to observe the local electrical fields in a membrane,
- high-k capacitors for extracellular stimulation of neuronal systems,
- low noise transistors for extracellular recording in neuronal systems,
- micropatterning techniques to control neuronal networks, and
- CMOS chips with thousands of capacitors and transistors for high-resolution interfacing of neuronal networks and brain tissue.

The department relies on an integration of semiconductor technology, molecular spectroscopy, colloid physics, neurophysiology, and molecular biology, both with respect to the experimental techniques and the theoretical concepts.

Review "Neuroelectronic Interfacing" available.

Neuron from rat brain on a linear array of field-effect transistors. The ionic current in the cell interacts with the electronic current in the silicon.

Network of snail neurons on a silicon chip. The cell bodies (dark blobs) are immobilized by picket fences on two-way contacts of capacitive stimulation spots and field effect transistors. They are joined by neurites (bright threads) with electrical synapses.

             

Electrical field potential in organotypic hippocampus slice culture measured by MTA recording 5 ms after stimulation. The spatiotemporal dynamics can be observed in the movie (Quicktime, 8 MB)