Coplanar Waveguide Sensor for Dimethyl Methyl Phosphonate (DMMP) Vapor Detection at Microwave Frequencies

The development of a palladium-based Coplanar Waveguide (CPW) microwave sensor for detecting Dimethyl methyl phosphonate (DMMP) vapor is designed, fabricated, and tested in this paper. The sensor is fabricated using a thin palladium layer on a planar quartz substrate. Microwave transmission loss variations were used to identify the presence of DMMP vapor in a controlled environment. The presence of 400 parts per million (ppm) DMMP caused detectable changes in the transmission (S21) and admittance (Y11) parameters.