"Electron Tunneling for Microminiature Sensors to Detect Acceleration or Mechancial Vibration"

Period of Performance: 01/13/1995 - 07/13/1995


Phase 1 STTR

Recipient Firm

PCB Piezotronics, Inc.
3425 Walden Ave
Depew, NY 14043
Principal Investigator
Firm POC

Research Institution

University of Rochester
518 Hylan, River Campusbox 27014
Rochester, NY 14627
Institution POC

Research Topics


Tunneling of electrons between two closely spaced metal electrodes will be experimentally researched to assess the practical potential as a transduction mechanism for microfabricated accelerometers and vibration sensors. The characteristic length scale for electron tunneling is subnanometer, so changes in a tunneling gap of only a few Angstroms can cause an order of magnitude change in a nanoampere tunneling current. This extraordinary sensitivity to displacements promises to form the basis for a new class of sensors for acceleration, vibration, or any quantity that can be transformed into a relative displacement of two electrodes. Early, fundamental work carried out at the University of Rochester on mechanical interactions between tunneling electrodes, tunneling electrode work functions, calibration measurements, and tunneling current fluctuations has shown that tunneling has the potential to be the most sensitive means available for displacement monitoring in the micro-sensor arena. The goal of the proposed project is to determine if tunneling has the required stability and repeatability to form the basis fo a commercial sensor technology. To meet this goal PCB Piezotronics, Inc. and the University of Rochester will prepare a variety of microfabricated tunneling tips and counter electrodes and perform calibration and noise measurements to search for tunneling materials, sample preparation and ambient operating environments that give the most stable and repeatable tunneling currents and work functions. If our proposed work so indicates, in the late stage of the project we ill develop degtailed design and fabrication process for a microfabricated tunneling based accelerometer.