Enhanced microwave shielding effectiveness of ultrathin pyrolytic carbon films

Electromagnetic properties of pyrolytic carbon (PyC) films with thickness from 5 to 241 nm are studied experimentally and numerically at 28 GHz. We observe experimentally that PyC films are capable to absorb up to 50% of microwave power in the K-a-band. By using boundary conditions in the rectangular waveguide, we demonstrate theoretically that 50% of microwave power can be absorbed in a conductive film with thickness much smaller than the skin depth. The results of modelling for PyC films on silica substrate are in excellent coincidence with the experimental data. (C) 2013 AIP Publishing LLC.