Properties of M-AFM probe affected by nanostructural metal coatings

Abstract

In order to develop a new structure microwave probe, the fabrication of the atomic force microscope (AFM) probe on a GaAs wafer was studied and characteristics of the AFM probe with different nanostructural metal coating were evaluated in order to understand the performance of the probe for the topography of materials and the propagation of microwave signals. The fabricated probe had a tip of 8 µm high and curvature radius approximately 30 nm. The dimensions of the cantilever are 250×30×15 µm. A waveguide was introduced by the sputtering and the electron beam (EB) evaporation technique on the top and bottom surfaces of the GaAs AFM probe with Au or Al film. The open structure of the waveguide at the tip of the probe was introduced by using focused ion beam (FIB) fabrication. AFM topography of a grating sample was measured by using each fabricated probe. It was found that the fabricated probes coated with the Au or Al film have nanometer order resolution. Moreover, using the Au-coating probe formed by the EB evaporation technique, microwave emission was detected successfully at the tip of the probe by approaching an Au film sample.