Microfabricated silicon dioxide cantilever with subwavelength aperture

We have developed a microfabricated SiO2 cantilever with subwavelength aperture for scanning near‐field optical microscopy (SNOM), to overcome the disadvantages of conventional optical fibre probes such as low reproducibility and low optical throughput. The microcantilever, which has a SiO2 cantilever and an aperture tip near the end of the cantilever, is fabricated in a reproducible batch process. The circular aperture with a diameter of 100–150 nm is formed by a focused ion‐beam technique. Incident light is directly focused on the aperture from the rear side of the cantilever using a focusing objective, and high optical throughput (10−2 to 10−3) is obtained. The microcantilever can be operated as a SNOM probe in contact mode or in dynamic mode.