Optical Coefficients of the Layered Structure with Nanometer Copper Film in the Frequency Band 8.5 – 12.5 GHz, Depending on the Substrate Thickness

The spectral dependence of the optical coefficients of ultrathin copper films 2 – 30 nm thick on the substrate thickness has been studied. The measurements were carried out in a rectangular waveguide in the frequency range 8.5–12.5 GHz for two orientations of the film with respect to the direction of the incident wave. 4 mm to a 4 mm substrate with a film. It is shown that the effect of anomalously high absorption of waves (more than 77%) by copper films no thicker than 10 nm is observed in a wide frequency band. The effect of extremely low reflection (0.06%) was registered when a wave of frequency 11.54 GHz is incident on a film 7.9 nm thick from the side of a 4-mm substrate. It is shown that the frequency range where the effect of minimal reflection was observed exceeds the antireflection band of a dielectric plate with half-wave resonance.