ABSTRACT
A high transmission probe for scanning near-field optical microscopy is discussed that is based on a bow-tie antenna. The proposed design of the transmission line probe relies on batch-fabricated hollow pyramidal silicon dioxide tips that are partly coated with aluminium to accomplish the tapered dipole antenna. Theoretical calculations of the field distribution were performed to investigate its optical properties. Results were compared with those of conventional aperture tips based on the same silicon dioxide tip configuration, and revealed unique properties with respect to the transmission efficiency.
ABSTRACT
We report the development of cantilever- and fibre-based probes for scanning near-field optical microscopy. Both probe concepts rely on the integration of a microfabricated aperture tip with reproducible optical and mechanical properties. Numerical calculations were carried out using a finite integration code to investigate the polarization-sensitive transmission behaviour of aperture tips. In order to establish technological guidelines for the optimization of the properties of the optical tip the distinct influence of the tip geometry on the intensity distribution in the vicinity of the aperture is studied in detail.
ABSTRACT
This paper deals with the development of coaxial aperture tips integrated in a cantilever probe for combined scanning near-field infrared microscopy and scanning force microscopy. A fabrication process is introduced that allows the batch fabrication of hollow metal aperture tips integrated on a silicon cantilever. To achieve the coaxial tip arrangement a metal rod is deposited inside the hollow tip using the focused ion beam technique. Theoretical calculations with a finite integration code were performed to study the transmission characteristics of coaxial tips in comparison with conventional aperture probes. In addition, the influence of the geometrical design parameters of the coaxial probe on its optical behaviour is investigated.
