AVS 51st International Symposium
    MEMS and NEMS Tuesday Sessions
       Session MN-TuM

Paper MN-TuM5
Tribological and Wear Studies of ALD and SILAR Coatings for MEMS Devices

Tuesday, November 16, 2004, 9:40 am, Room 213C

Session: MEMS and NEMS: Enabling Tools for Scientific Research
Presenter: C. Nistorica, Zyvex Corporation
Authors: C. Nistorica, Zyvex Corporation
J.-F. Liu, Zyvex Corporation
I. Gory, Zyvex Corporation
G.D. Skidmore, Zyvex Corporation
F.M. Mantiziba, University of Texas at Dallas
B.E. Gnade, University of Texas at Dallas
J. Kim, Kookmin University, Korea
Correspondent: Click to Email
This paper describes a study of the static friction and wear of coated microelectromechanical systems (MEMS) using thermally actuated friction micro-devices. In order to characterize static friction and wear, a tribological deep reactive ion etched (DRIE) silicon test microstructure is developed. Reproducibility of the data is proved by testing multiple devices in parallel. Conformal coatings consisting of 10 nm thick atomic layer deposited (ALD) TiO@sub 2@ or ZrO@sub 2@ and successive ionic layer adsorption and reaction (SILAR) deposited MoS@sub 2@ or ZrO@sub 2@ films are applied on the MEMS silicon test devices. The effect of film roughness, velocity as well as the effect of humidity on friction and wear is studied by exposing the coated MEMS devices to a relative humidity varying between 5% and 100%. The coatings were found to behave differently, ZrO@sub 2@ and MoS@sub 2@ decreasing the coefficient of friction by 40% compared to uncoated devices, while TiO@sub 2@ presented a decrease in the coefficient of friction only at higher humidity. The wear data for the ALD coated devices, quantified from the point of view of debris creation and stability of the friction coefficient, indicate much improvement over native oxide coated silicon devices, while the SILAR coatings showed high wear.