Surface Treatments Effects for NO_2 Gas Responsivity of p-Type Surface Conductive Layer on Diamond Films

摘要

The low resistance layer called p-type Surface Conductive Layer (PSCL) is formed when the nitrogen dioxide (NO_2) was absorbed onto hydrogen-terminated surface, although the diamond is generally isolator. The PSCL conductance is dependent on NO_2 concentration in the atmosphere, and this reaction has reversibility. The diamond having these characteristics can apply to gas sensor. In this study, the gas responsivity of PSCL was improved by surface treatment. The changes in the responsivity were evaluated from serial measurements of the conductance in the gas atmosphere. From this evaluation, it was observed that the adsorption and desorption of NO_2 were faster via the surface conditions variation by treatment.