Alkoxyl monolayers as anti-stiction coatings in Si-based MEMS devices

Yongseok Jun, Xiaoyang Zhu

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

Reducing surface energy is key to the success of many microelectromechanical systems (MEMS). In this report we present a strategy for the efficient assembly of alkoxyl monolayers onto a silicon surface to control surface energy. This is achieved by an all-liquid process in which the hydrogen terminated silicon surface resulting from aqueous HF etching is coated with a close-packed alkoxyl monolayer. The adhesion to silicon surface is reduced by a factor of 40 by the monolayer coating and friction coefficient of the coated surface is only 10 -2. These coatings are successfully implemented in a model MEMS structure: cantilever beam array (CBA). Release-stiction is eliminated for polycrystalline silicon beams with a thickness of only 2 μm but with lengths up to 2 mm. Electrostatic actuation of coated beams in a controlled environment shows that the monolayer coating prevents in-use stiction at relative humidity as high as 90%.

Original languageEnglish
Pages (from-to)593-601
Number of pages9
JournalJournal of Adhesion Science and Technology
Volume17
Issue number4
DOIs
Publication statusPublished - 2003 Dec 1
Externally publishedYes

Fingerprint

stiction
Stiction
Silicon
microelectromechanical systems
MEMS
Monolayers
coatings
Equipment and Supplies
Coatings
silicon
Interfacial energy
surface energy
Controlled Environment
control surfaces
Friction
Control surfaces
cantilever beams
Cantilever beams
Humidity
Static Electricity

Keywords

  • friction
  • MEMS
  • Monolayer coating
  • self-assembled monolayer.
  • silicon
  • stiction
  • surface energy

ASJC Scopus subject areas

  • Chemistry(all)
  • Mechanics of Materials
  • Surfaces and Interfaces
  • Surfaces, Coatings and Films
  • Materials Chemistry

Cite this

Alkoxyl monolayers as anti-stiction coatings in Si-based MEMS devices. / Jun, Yongseok; Zhu, Xiaoyang.

In: Journal of Adhesion Science and Technology, Vol. 17, No. 4, 01.12.2003, p. 593-601.

Research output: Contribution to journalArticle

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