Vapour HF etcher

The first of its kind in Canada, the nanoFAB is pleased to announce the addition of a memsstar Orbis Alpha Vapour HF etcher to our toolset. Historically, fabricating mechanical structures prone to stiction necessitated the use of HF-based wet etching of sacrificial oxide followed by critical point drying. Using vapour-phase HF etching, however, stiction-free device release is now possible in a single processing step. With memsstar’s unique dry anhydrous oxide etch technology, a wide range of sacrificial oxide materials can be selectively etched without damaging underlying device layers.

The tool accommodates substrates from small pieces up to 200 mm in diameter, is equipped with backside gas protection to prevent etching of backside oxide from 100 mm and 150 mm wafers, and features an NDIR-sensor for precise process monitoring and endpoint detection (see figure to the right).

For more information, please contact Aaron Hryciw. Any nanoFAB users wishing to use this tool should submit a training request via LMACS.

memsstar-soi-ndir NDIR process monitor trace for an SOI MEMS device release recipe, in which an increase in the concentration of the gaseous product SiF₄ is manifested by a rise in signal. The transition from field clear (etching BOX open areas down to the Si handle) to pure device undercut is clearly delineated on such a plot.