Advances in the miniaturization of semiconductor devices have been made possible by new methods of microfabrication
techniques . These advances have stimulated the birth of Micro Electro Mechanical Systems (MEMS) technology which
enable the fabrication of a wide variety of sensing and actuating devices of microscopic dimensions . Of particular
interest are thermal microactuators which provide large deflections and are compatible with existing IC technologies. In
MEMS technology, a well controlled etching process is critical for the fabrication of structures with specific geometry
and properties. Increasing demand for intricate semiconductor devices has fueled and motivated researches to develop
high precision micromachining techniques . Inductively coupled plasma- Reactive ion etching (ICP-RIE) is capable of
producing features with high aspect ratio as high as 90:1. Taking advantage of the notching effect when making a
structure from silicon on insulator (SOI), structure release without the use of HF acid has been demonstrated. We report
on the development of a self-aligned single-mask process for the fabrication of released and movable MEMS devices.
ICP-RIE was used to realize the structures directly out of single crystal silicon. Applying side wall passivation,
controlling the ratio of ion flux and radical flux, smooth etching profile can be obtained with high aspect ratio. No wet
etching process is required to release the structures as is the case with SOI wafers. This approach overcomes the stiction
limitation associated with wet etching and yields good thickness uniformity over the entire structure. Electrothermal
microactuators with integrated microgrippers were designed, fabricated and characterized.