Integrated multisensor chip

A multipurpose integrated-sensor chip has been fabricated for the simultaneous measurement of physical and chemical variables. The multipurpose chip which measures 8 × 9 mm²contains conventional MOS devices for signal conditioning, array accessing, and output buffering along with the following on-chip sensors: a gas-flow sensor, an infrared-sensing array, a chemical-reaction sensor, cantilever-beam accelerometers, surface-acoustic-wave (SAW) vapor sensors, a tactile sensor array, and an infrared charge-coupled device imager. The multisensing functions of this chip utilize both the pyroelectdc and piezoelectric effects in ZnO thin films. Fabrication of the chip is carried out using a conventional 3-µm Si NMOS process combined with Si micromachining techniques. Compatible fabrication technology and sensor properties are described.