A femtosecond laser beam focused inside fused silica and other glasses can modify the refractive index of the glass. Chemical etching and atomic-force microscope studies show that the modified region can have a sharp-tipped cone-shaped structure with a tip diameter as small as 100 nm. Placing the structure near the bottom surface of a silica glass sample and applying a selective chemical etch to the bottom surface produces clean, circular, submicrometer-diameter holes. Holes spaced as close to one another as 1.4 μm are demonstrated.
© 2003 Optical Society of America
[Optical Society of America ]
R. S. Taylor, C. Hnatovsky, E. Simova, D. M. Rayner, V. R. Bhardwaj, and P. B. Corkum, "Femtosecond laser fabrication of nanostructures in silica glass," Opt. Lett. 28, 1043-1045 (2003)