Online proceedings - EDA Publishing Association

7-9 October 2009, Leuven, Belgium
B. Static Analysis
To analyze the initial response of the proposed device,
static analysis is performed. This analysis calculates the
results for the stress distribution, displacement distribution
and mechanical deformation of the structure. In case of
the thermally actuated microdevices like the proposed
one, static analysis generally comprised of thermalelectrical
and thermal-stress analyses. Thermal-electrical
analysis solves coupled thermal electrical equations
whereas thermal-stress analysis calculates mechanical
stresses in the device due to the thermal loads calculated
during the thermal-electrical analysis [10].
Predicted displacement vs. voltage and temperature vs.
voltage plots are presented in Fig. 7. Static analysis is
carried out over a range of applied static voltages from
0.10-0.13V with an increment of 0.05V. The results Fig. 9. Temperature profile predicted by the Static analysis at 0.1V dc.
showed that achieved displacements and temperatures are
the function of the V 2 at constant resistivity. A drive
C. Dynamic Analysis
displacement of 109 µm/V along with a temperature rise FEA based dynamic simulation results are shown in
of 640 o C/V predicts that voltage-stroke ratio of the Fig. 10. The thermal actuator was driven by a sinusoidal
proposed device is very high in comparison with voltage of 0.1V at 2.51 kHz, half of the operating
electrostatic comb drives. Displacement and temperature frequency as one sinusoidal cycle results in two complete
profile of the device at 0.10V DC is shown in Fig. 8 and 9. cycles of the thermal actuator [4]. The predicted drive
A predicted displacement of 4.88 µm with a temperature displacement achieved by the proof mass is 0.28µm
of 52 o /C is achieved by the device at this voltage.
(shown blue in Fig. 10(a)). The temperature profile
developed across the device when subjected to the same
voltage excitation signal is shown in Fig. 10 (b).
Fig. 7. Predicted drive direction displacement and maximum temperature
at different applied static voltages.
(a)
Fig. 8. Displacement profile predicted by the Static analysis at 0.1V dc.
(b)
Fig. 10. (a) Displacement and (b) temperature profile predicted when the
Dynamic analysis is carried at 0.1V ac applied at 2.51kHz.
©EDA Publishing/THERMINIC 2009 43
ISBN: 978-2-35500-010-2