Stabilized Pd-alloy/AlN/Si Hydrogen Sensors

摘要

In order to extend the dynamic range of a hydrogen sensor with a metal-insulator-semiconductor (MIS) type structure, Pd-Cr and Pd-Ni alloy gated samples wertsstudied. The Pd-Cr gated sample shows quite stable and reproducible response, and could measure hydrogen concentrations from 100 to 50,000 ppm. While the Pd-Ni gated sample shows turn-on/off response drift, this drift is probably due to the presence of oxygen on the surface of the insulator and the formation of metal hydride. Furthermore, the effect of oxygen on the sensors response was investigated; oxygen may deplete protons from the metal/insulator interface and could reduce the sensor's response.