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Thin Film BAW Composite Resonator simulation in COMOSL 3.5a


I'm currently engaged in the simulation of FBAR device in COMSOL 3.5a, and want to use this model.

However, "in the model library", I find that the admittance of electrode is defined as "0.5[mm]*nJs_smppn/1[V]", where 0.5[mm] is the width of the electrode, and "nJs_smppn" is the surface current density, which I don't know why, because we use the integration coupling variables, and the width of the electrode is the variable.

Then why we use the "0.5[mm]*nJs_smppn/1[V]", but not the "1.7[mm]*nJs_smppn/1[V]", where 1.7[mm] is the thickness of the 2D scheme of FBAR device.

3 Replies Last Post 2013年4月18日 GMT-0400上午4:20
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Hello Jianan Wang

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Vidya Shree Niranjan
Posted: 5 years ago 2013年1月3日 GMT-0500下午12:19
Hi Jianan Wang,

Myself Vidya Shree, I am trying to develop the same Thin Film BAW Resonator, using version 4.2, So I request you to give me some detail about developing the model which will help me in my studies. I am new to Comsol product an I even not got procedure model of BAW resonator which is developed using version 3.5.
Hi Jianan Wang, Myself Vidya Shree, I am trying to develop the same Thin Film BAW Resonator, using version 4.2, So I request you to give me some detail about developing the model which will help me in my studies. I am new to Comsol product an I even not got procedure model of BAW resonator which is developed using version 3.5.

Yanamandra Sri Krishna
Posted: 5 years ago 2013年1月7日 GMT-0500上午3:04
Hello vidya and Jianan,
I'm working on Design and Analysis of Thin Film Bulk Acoustic Resonator. I'm new to the COMSOL. Can you please suggest the design considerations for designing BAW for particular resonant frequency, what relationship or formula should I establish between resonant frequency and electrode thickness, thickness of substrate, etc. Please help.
Thanks in advance
Hello vidya and Jianan, I'm working on Design and Analysis of Thin Film Bulk Acoustic Resonator. I'm new to the COMSOL. Can you please suggest the design considerations for designing BAW for particular resonant frequency, what relationship or formula should I establish between resonant frequency and electrode thickness, thickness of substrate, etc. Please help. Thanks in advance

Vidya Shree Niranjan
Posted: 5 years ago 2013年4月18日 GMT-0400上午4:20
Hi Krishna
Did you get any answer for your problem. if yes mail me Vidu054@gmail.com
Hi Krishna Did you get any answer for your problem. if yes mail me Vidu054@gmail.com

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