Focused ion-beam fabrication of fiber probes for use in near field scanning optical microscopy

A method of forming a fiber probe having an aperture for use in near-field scanning optical microscopy comprising the steps of:

• coating an optical fiber having a tapered tip with a metal layer;
• and
• focused ion-beam milling the tapered tip and metal layer such that an aperture is formed through the metal layer at the tapered tip,
• wherein said step of focused ion-beam milling comprises raster scanning the focused ion-beam in a rectangular pattern at an apex of the tapered tip such that portions of the metal layer and tapered tip are removed at the apex, forming said aperture through the metal layer.

A method of forming a fiber probe with an aperture for use in near-field scanning optical microscopy comprising the steps of:

• (a) forming a tapered tip-at an end of an optical fiber;
• (b) coating said tapered tip with an aluminum layer;
• and
• (c) focused ion-beam milling a portion of the tapered tip and aluminum layer such that an aperture is formed through the aluminum layer at the end of the optical fiber, wherein said step (c) comprises raster scanning the focused ion-beam in a rectangular pattern at an apex of the tapered tip.