Innovation and Partnerships Office

Analytical Scanning Evanescent Microwave Microscope and Control Stage IB-1506


  • Scanning probe microscopy


  • Non-contact and high resolution measurements avoid damage to both the probe tip and test specimen
  • Enables more accurate control of the gap distance between the probe tip and test specimen


Scientists at Berkeley Lab have developed a scanning evanescent microwave microscope (SEMM) that uses near-field evanescent eletromagnetic waves to probe sample properties. The SEMM is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The SEMM has the ability to map dielectric constant, loss tangent, conductivity, electrical impedance, and other electrical parameters of materials. Such properties are then used to provide distance control over a wide range, from microns to nanometers, over dielectric and conductive samples for a scanned evanescent microwave probe, which enables quantitative non-contact and submicron spatial resolution topographic and electrical impedance profiling of dielectric, nonlinear dielectric and conductive materials.

The invention also allows quantitative estimation of microwave impedance using signals obtained by the scanned evanescent microwave probe and quasistatic approximation modeling. The SEMM can be used to measure electrical properties of both dielectric and electrically conducting materials.

A piezoelectric stepper for providing coarse control of the tip-sample separation in a scanned evanescent microwave probe with nanometer step size and centimeter travel distances is also disclosed.

For more information, see Issued U.S. Patent 7,550,963.

STATUS: Issued U.S. Patent 7,550,963. Available for licensing or collaborative research.