High-precision and low-damage machining of transparent materials

is one of the challenges of current laser materials process-

ing to enable new applications in ultraprecise surface machin-

ing, microsystems technology, nanotechnology, and information

technology.1−3 Patterning, micromachining, modification, and surface shaping of such materials can also be performed with a

number of traditional processes. Lithography combined with wet

or dry etching is well known but requires multiple-step process

technology that involves photolithographic masking and pattern

transfer. Submicron resolution can be achieved by using this

approach, but 3D topographies require considerably more effort.4,5

In addition, the pattern transfer into chemically stable materials,

such as fluorides, by either chemical etching or physical sputtering

is sophisticated.6 Instead of pattern transfer, photosensitive glass

enables the fabrication of microstructures through direct exposure

of the material and subsequent wet etching, but limitations in the

material and the achievable surface quality still exist.