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Hello, I am working with a 3-layer cantilever beam: the main strucure is made of silicon which is covered with a silicon oxide layer, and above that there is a thin Aluminium layer. My job is to apply electric potential on the Al layer which will then be heated. Then, the heat will transfer to the Si layer via SiO2 layer. Due to difference in thermal expansion coefficient, the cantilever will deflect.

At first, I applied DC volatge at one end of the Al wire and ground a the other end. There was a fixed deflection of the cantilever beam. After that, I applied AC sinusoidal voltage V0sin(2pift) at one end and ground at the other end of the Al layer. Then, I checked the voltage change at the source point using 1D plot -> point graph. Now, for low frequency (e.g. f=1~10 Hz), the voltage graph is slightly distorted (not perfect sinusoidal), and for high frequency (e.g. f~1000 Hz), the voltage graph gives one wave cycle and then becomes DC (e.g. from 0V to 100 mV to -100 mV to fixed 100 mV for rest of the time).

I used joule heating and thermal expansion module with frequecy-transient study. The max. simulation time was 10~100 miliseond and the time step was chosen 1~10 microsecond.

It will be helpful for me if someone can give some insights who had worked with similar stuff, and faced similar problem. (See the attachment for more clarification).

Thanking in advance, Ekram H. Khan.