Optimised cantilever biosensor with piezoresistive read-out

We present a cantilever-based biochemical sensor with piezoresistive read-out which has been optimised for measuring surface stress. The resistors and the electrical wiring on the chip are encapsulated in low-pressure chemical vapor deposition (LPCVD) silicon nitride, so that the chip is well suited for operation in liquids. The wiring is titanium silicide which—in contrast to conventional metal wiring—is compatible with the high-temperature LPCVD coating process.