Nondestructive characterization of various thin films using a near-field scanning millimeter-wave microscope

Abstract

We demonstrate a nondestructive millimeter-wave surface imaging technique using a near-field scanning millimeter-wave microscope (NSMM) with a resonant standard waveguide probe at an operation frequency f=30-39GHz. A chemically etched metallic probe tip, was coupled to the resonant rectangular waveguide. By properly tuning the tunable resonator and the probe tip, we could improve sensitivity and spatial resolution of the NSMM. Measuring the change of the reflection coefficient S11 in the near-field zone, sheet resistance changes of Ag, ITO, YBa2Cu3Oy, organic copper(II) phthalocyanine (Cu-Pc) thin films, and MgO were obtained. We observed the NSMM images of Ag thin film on the glass substrate with a spatial resolution better than 2 μm. © 2004 Elsevier B.V. All rights reserved.