Question about constructing cavity in HFSS design

[anglerep]

piezoloelectric hfss

Hi, everyone:
I need to construct a cavity in my HFSS design. I did it by creating two boxes: one big and one small, and then substract the small box from the big box. My question is: since the cavity is a part of the resonator, should I put in an air box (the same size as the small box) to simulate there is air inside the cavity?
BTW what's the recommend memory size for HFSS simulation, mine is 512MB, it takes a long time to do a simulation.

Thanks,

 

[ananth]

piezoelectric hfss

Hey anglerep,
I don't think u need to put an airbox in your cavity.. U could probably give it a try and see if it makes a difference in your results.. but I wouldn't think u'll need it.
As far as memory goes, the more the better but u shud be able to handle things well with 512 MB of RAM.

Ananth.

 

[hamidmoghaddas]

hfss fbar

hi
1024 MB is ok
a real resonator has air inside. so include it.

 

[anglerep]

piezoelectric hsff

Actually I'm not quite sure this structure I am building can use HFSS to simulate. If you are familiar with FBAR (it's a bulk resonator) You will understand better this situation. Basicly I need to have a piezoelectric material with certain thickness, and two electrodes, one on the top of the piezoelectric material, and one at the bottom. Under the bottom electrode metal locates this cavity. When input RF signal comes, the piezoelectric material will vibrate and with the help of the cavity it will resonant at certain frequency. I am designing the structure so that the resonance happens at about 2GHz. I cannot figure out how to input the piezoelectric material property into HFSS, or is it possible? or is there any way I can get around it? Or any other software can do this job? Any advice is appreciated.

Ang.

 

[Carleone]

Re: cavity in HFSS

Hi there!Most people use Ansys to simulate the FBAR for electromechanical simulations .I would also be interested in finding out about any HFSS FBAR simulations.Please send me a mail if you discovered stg.

 

[lynne]

Re: cavity in HFSS

you can set the small box use you desire material
then use the boolean --substract ,but remmber checking the clone the two object before substact ,then you can have maitained the cacity attribute and needn't set the cavity with air