Heavy ion induced etch anisotropy in single crystalline quartz

Micromachining by ion track etching (MITE) offers a new way to impose an arbitrary etch anisotropy on amorphous and crystalline dielectrics and is demonstrated in single crystalline quartz. The technique can be used to obtain very deep structures with extreme aspect ratios and line widths. At present, depths down to several hundred micrometers with aspect ratios larger than 100 can be obtained. The MITE process has been explored using single crystalline quartz of the AT-cut and Z-cut orientations, using fast heavy ions ¹⁹⁷Au and ¹²⁹Xe (11.6 MeV/u and 11.4 MeV/u, respectively). Complex, three-dimensional quartz structures of 80 μm height with vertical or inclined walls were produced. The and limitations of the process are discussed