TY - JOUR
T1 - Characterization of stiction accrual in a MEMS
AU - Ranganathan, Ranjith
AU - Sivakumar, Ganapathy
AU - Gale, Richard
AU - Dallas, Tim
N1 - Funding Information:
Manuscript received February 5, 2009; revised June 10, 2009. First published September 1, 2009; current version published September 30, 2009. This work was supported in part by the National Science Foundation under Grant ECS 0326218, in part by the Welch Foundation under Grant D-1651, and in part by the TTU Vice President for Research Office. Subject Editor G. K. Fedder.
PY - 2009
Y1 - 2009
N2 - Stiction remains one of the chief reliability concerns for microelectromechanical systems (MEMS) devices. In this paper, we quantify and analyze the rate of accrual of stiction in a standard MEMS device under a set of controlled temperature and humidity splits. An accelerated aging system was employed to more rapidly induce stiction in the MEMS. Optical characterization techniques were used to study the progression of stiction. The stiction accrual was quantified in terms of stiction equivalent energy, which provides compensation for mechanical fatigue in the devices due to long periods of operation. The fastest accrual of stiction was seen in the 90 °C, 80% relative humidity (RH) split with approximately 80% of the MEMS elements failing within 4.4 × 109 cycles (10 h) with 2.7 × 10-14 Joules of Stiction Equivalent Energy while the 60 °C, 20% RH showed the least stiction accrual rate with less than 2% failure for 2.26 × 1012 cycles (1500 h). In general, the stiction was seen to increase with an increase in humidity while mechanical fatigue showed an increase with an increase in temperature. Atomic force microscopy topography imaging was used to assess physical wear at the contacting areas. The results revealed that there were not any discernable changes in the surface profile due to long periods of actuation.
AB - Stiction remains one of the chief reliability concerns for microelectromechanical systems (MEMS) devices. In this paper, we quantify and analyze the rate of accrual of stiction in a standard MEMS device under a set of controlled temperature and humidity splits. An accelerated aging system was employed to more rapidly induce stiction in the MEMS. Optical characterization techniques were used to study the progression of stiction. The stiction accrual was quantified in terms of stiction equivalent energy, which provides compensation for mechanical fatigue in the devices due to long periods of operation. The fastest accrual of stiction was seen in the 90 °C, 80% relative humidity (RH) split with approximately 80% of the MEMS elements failing within 4.4 × 109 cycles (10 h) with 2.7 × 10-14 Joules of Stiction Equivalent Energy while the 60 °C, 20% RH showed the least stiction accrual rate with less than 2% failure for 2.26 × 1012 cycles (1500 h). In general, the stiction was seen to increase with an increase in humidity while mechanical fatigue showed an increase with an increase in temperature. Atomic force microscopy topography imaging was used to assess physical wear at the contacting areas. The results revealed that there were not any discernable changes in the surface profile due to long periods of actuation.
KW - Contact modeling
KW - Mechanical fatigue
KW - Microelectromechanical devices
KW - Stiction
KW - Weibull
UR - http://www.scopus.com/inward/record.url?scp=70350001141&partnerID=8YFLogxK
U2 - 10.1109/JMEMS.2009.2027503
DO - 10.1109/JMEMS.2009.2027503
M3 - Article
AN - SCOPUS:70350001141
SN - 1057-7157
VL - 18
SP - 1149
EP - 1159
JO - Journal of Microelectromechanical Systems
JF - Journal of Microelectromechanical Systems
IS - 5
ER -