Ion and electron beam assisted growth of nanometric SimOn structures for near-field microscopy

We report the fabrication of nanometric, conformal, smooth dielectric coatings on the ends of apertureless near-field optical probes by both ion beam and electron beam assisted deposition techniques (IBAD and EBAD). The ion beam provides a higher SimOn growth rate than the electron beam, though the undesirable implantation of Ga ions may outweigh the benefits of rapid growth. Wavelength dispersive x-ray spectroscopy reveals that the electron beam deposited dielectric has a stoichiometry of SinO2n. We present two near-field optics applications of EBAD and IBAD grown dielectric layers. EBAD deposited coatings can be used to reduce fluorescence quenching in apertureless near-field scanning optical microscopy, while IBAD fabricated structures are suited for micro/nano-optics.