RELIABLE HYBRID GASFETS FOR WORK-FUNCTION MEASUREMENTS WITH ARBITRARY MATERIALS

We have developed a novel hybrid technique for manufacturing gas-sensing field-effect structures (GasFETs) with an air gap. To prove the efficiency of the device, gas measurements with the well-known Pt (sensitive layer) and H-2 (gas) system have been carried out at room temperature. Samples produced identically show reproducible signals of the same magnitude. Simultaneously, we have recorded the electrical response of a platinum-coated Kelvin probe. Results obtained by the hybrid GasFETs are transferrable to those obtained by the Kelvin probe. With the new technology for device fabrication, our transducer meets the requirements for measuring work-function changes caused by gases on a wide variety of sensitive layers.