銅製導波管在厘米波段中之表面導電率

Abstract

Surface conductivities of waveguides having different wall conditions were examined via the insertion loss technique and Q-technique. It is found that ordinary copper plated waveguide samples are usually about 12% to 19% above the calculated value based upon a wall conductivity 5.8 10^7 mho/m in the frequency range of 40 to 110 GHz. When the copper waveguides described above are subjected to additional surface treatment (usually imparted to promote dielectric bonding) , the losses may or may not change depending on the nature of the surface treatment. for example, a chromated (probably Cr2O3) layer up to 300 A will not cause significant added losses in the mm wave frequency band. On the other hand, a surface treatment consisting of a grown copper oxide film (Cu2 and CuO)will cause a significant increase in loss relative to plated but untreated copper. This additional loss is approximately 20% at 96 GHz.