The steady state temperature profiles of U- and I-shaped electrothermal microactuators are analytically derived. The temperature profiles could be used to evaluate the performance sensitivity of the microactuator due to various parameter changes. In this work, the analysis assumes an unpackaged silicon microactuator with an air gap between the actuator and substrate and the profiles are evaluated for various input voltage amplitudes. It was found that at low voltage inputs the temperature profile is exponential in nature with the failure being due to thermo-structural stresses and/or structure melting. At voltages larger than a critical value, a combined sinusoidal and exponential temperature profile is observed with the failure being strongly due to structural melting as well. However, higher voltage excitation causes a fully distributed sinusoidal temperature profile. In this mode, failures occur at different locations and due to high localized thermal stresses causing the temperature to exceed the material melting point. The behavior of U- and I-shaped microactuators based on silicon on insulator (SOI) fabrication and femtosecond laser micromachining was experimentally examined with the results corroborating the conclusions drawn from the analysis.

Volume Subject Area:
Microelectromechanical Systems
Topics:
Microactuators, Temperature profiles, Failure, Melting, Silicon-on-insulator, Actuators, Excitation, Lasers, Manufacturing, Melting point, Micromachining, Silicon, Steady state, Stress, Temperature, Thermal stresses
1.
Wener Riethmulle, and Wolfgang Benecke, thermally excited silicon microactuator, IEEE transaction on electron devices, Vol. 35, No. 6, June 1988.
2.
Pany
Chi Shiang
and
Hsu
Wensyang
,
An electro-thermally and laterally driven polysilicon microactuator
,
J. Micromech. Microeng.
7
(
1997
)
7
–
13
.
3.
Field
Leslie A.
,
Burriesci
Diane L.
,
Robrish
Peter R.
, and
Ruby
Richard C.
,
Micromachined 1 x 2 optical-fiber switch
,
Sensors and Actuators A
53
(
1996
)
311
–
315
.
4.
Corntois
John H.
, and
Bright
Victor M.
,
application for surface micromachined polysillcon thermal actuator
,
Sensors and Actuators A
58
(
1997
)
19
–
25
.
5.
Lin
LiWei
and
Chiao
Mu
,
Electrothermal responses of lineshape microstructures
,
Sensors and Actuators A
55
(
1996
)
35
–
41
.
6.
Guckel H, Klein J, Christenson T, Skrobis K, Landon M and Lovell E G 1992 Thermo-magnetic metal flexure actuators Technical Digest, IEEE Solid State Sensor and Actuator Workshop (Hilton Head Island, SC) pp 73-5.
7.
Butler
Jeffrey T.
,
Bright
Victor M.
, and
Cowan
William D.
,
Average power control and positioning of polysilicon thermal actuators
,
Sensors and Actuators
72
1999
88
–
97
.
8.
Brnas
D. M
, and
Bright
V. M.
,
Design and performance of a double hot arm polysilicon thermal actuator
,
Proc. SPIE
, vol
3224
,
1997
, pp.
296
–
306
.
9.
Huang
Qing-An
and
Lee
Neville Ka Shek
,
Analysis and design of polysilicon thermal flexure actuator
,
J. Micromech. Microeng.
9
(
1999
)
64
–
70
.
10.
Geretovszky
Zs.
,
Kelemen
L.
, and
Piglmayer
K.
,
Temperature distribution in multilayers covered by liquid layer and processed by focused laser beam
,
Applied Surface Science
106
(
1996
)
422
–
428
.
11.
Material proprieties are available at www.matweb.com.
12.
ANSYS Inc. Southpointe. 275 Technology Drive. Canonsburg, PA. 15317, http://www.ansys.com/products/cfx.
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