SCANNING MICROWAVE MICROSCOPY OF ACTIVE SUPERCONDUCTING MICROWAVE DEVICES

We have developed a scanning microwave microscope which can image feat ures with 20 mu m spatial resolution. The microscope consists of a sec tion of open-ended coaxial cable which is scanned over the surface of a planar sample. Images can be made in either passive anode, in which the reflectivity of the probe tip is measured as a function of positio n, or in or in active mode, in which stray fields from the sample are picked up by the scanning probe and measured with a vector demodulatio n circuit. We have imaged reflectivity variations of metallic and dete rmine the spatial resolution of the technique. Images are also present ed in active mode of a superconducting microwave device taken at liqui d nitrogen temperature.