Menu

Discussion Forum

New Discussion
Filtra

Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Problem specifying GaAs piezoelectric axes

Posted 1 mag 2012, 23:29 GMT-4 MEMS & Nanotechnology, MEMS & Piezoelectric Devices Version 4.2a 0 Replies

Jorge
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Hi all! I am having trouble trying to simulate a 2D model of a GaAs SAW resonator. I've built my 2D model using the guidelines form the Comsol tutorial "SAW Gas Sensor", which simulates a unitary cell of a LiNbO3 SAW structure using appropriate boundary periodic conditions. The LiNbO3 model seems to work fine, and I obtain resonant and antiresonat eigenmodes at 927.8MHz and 940.66MHz (see attached model).

As a next step towards what I really need to analyze, I need to change the substrate to GaAs. However, I am not able to tell Comsol which crystal orientation it should take into account (I need to simulate a substrate normal to the <001> diretion and wave propagation in the (110) direction). Obviously, if I only change the material of the substrate in my LiNbO3 model, I get very different resonances and odd behavior (see attached model). I am almost sure the problem is the orientation of the model axes with respect to the crystal planes of the substrate, but I have no idea of that is the convention used by Comsol to map its xyz axes to the crystal directions.

I have tried to decipher Comsol's mapping by using 3D models and rotating them along various directions, but still had no luck; without knowing how Comsol interprets the axes of my drawn model (or how to change the way it does), I am just getting nonsense results!

Thanks in advance for any help!

Cheers,

Jorge.




0 Replies Last Post 1 mag 2012, 23:29 GMT-4
COMSOL Moderator

Hello Jorge

Your Discussion has gone 30 days without a reply. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help.

If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base.

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.

Suggested Content