Online proceedings - EDA Publishing Association

2) Cavity width effect
To verify the influence of the cavity half-width r 2 on the
conductive behaviour of the sensor, a FEM simulation is
performed for a new set of parameters: r 2 =700µm,
h 1 =600µm, h 2 =10mm and T H =600K. The heat transfer
coefficient h H and the common mode temperature T CM are
extracted from this simulation and compared with the results
obtained from expressions 4, 5, 6 and 7. The obtained FEM
and model values are given in table II, which shows that the
results are approximately equal.
TABLE II. MODEL AND FEM RESULTS OF THE HEAT TRANSFER
COEFFICIENT AND THE COMMON MODE TEMPERATURE
r 2=700µm, h 1=600µm, h 2=10mm, T H=600K
Conduction Model FEM
h H (W.m -2 .K -1 ) 612 616
T CM (K) 369 371
Therefore, it seems that the model is valid when r 2 varies
but it should be verified further with other sets of
parameters.
3) Model validity using FEM simulations
(a)
11-13
May 2011, Aix-en-Provence, France
heater temperature may be strongly impacted for a given
biasing voltage.
In Figure 4, we plot the heat transfer coefficient h H (Fig.
4.a) and the common mode temperature T CM (Fig. 4.b)
extracted from FEM simulations versus those calculated
from the model. We clearly notice that the model and FEM
results are in good agreement. In both figures, the points
which diverge from the ideal curve correspond to very low
values of the cavity depth h 1 0.2r 2 ), the relative error between the model and
FEM results remains below 4%. To conclude, the validity
domain of the model is then verified for 200µm