Near‐field scanning microwave microscope with 100 μm resolution

We describe the operation of a simple near‐field scanning microwave microscope with a spatial resolution of about 100 μm. The probe is constructed from an open‐ended resonant coaxial line which is excited by an applied microwave voltage in the frequency range of 7.5–12.4 GHz. We present images of conducting structures with the system configured in either receiving or reflection mode. The images demonstrate that the smallest resolvable feature is determined by the diameter of the inner wire of the coaxial line and the separation between the sample and probe.