Scanning microwave microscopy of active superconducting microwave devices

We have developed a scanning microwave microscope which can image features with 20 mu m spatial resolution. The microscope consists of a section 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 position, 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 demodulation circuit. We have imaged reflectivity variations of metallic and determine the spatial resolution of the technique. Images are also presented in active mode of a superconducting microwave device taken at liquid nitrogen temperature.