Solved with COMSOL Multiphysics 5.0
1 | MICRORESISTOR BEAM
Microresistor Beam
Introduction
This example illustrates the ability to couple thermal, electrical, and structural analysis
in one model. This particular application moves a beam by passing a current through
it; the current generates heat, and the temperature increase leads to displacement
through thermal expansion. The model estimates how much current and increase in
temperature are necessary to displace the beam.
Although the model involves a rather simple 3D geometry and straightforward
physics, it provides a good example of multiphysics modeling.
Model Definition
Figure 1: Microbeam geometry.
A copper microbeam has a length of 13 μm with a height and width of 1 μm. Feet at
both ends bond it rigidly to a substrate. An electric potential of 0.2 V applied between
the feet induces an electric current. Due to the material’s resistivity, the current heats
up the structure. Because the beam operates in the open, the generated heat dissipates
into the air. The thermally induced stress loads the material and deforms the beam.
