Dynamic etching method for fabricating a variety of tip shapes in the optical fibre probe of a scanning near-field optical microscope

A novel etching method for an optical fibre probe of a scanning near-field optical microscope (SNORM) was developed to fabricate a variety of tip shap es through dynamic movement during etching, By moving the fibre in two-phas e fluids of HF solution and organic solvent, the taper length and angle can be varied according to the movement of the position of the meniscus on the optical fibre, This method produces both long (sharp angle) and short (wid e angle) tapered tips compared to tips made with stationary etching precess es, A bent-type probe for a SNOM/AFM was fabricated by applying this techni que and its throughput efficiency was examined, A wide-angle probe with a 5 0 degrees angle at the tip showed a throughput efficiency of 3.3 x 10(-4) a t a resolution of 100 nm.