modeling stripline with hfss
Hi Itafrenkel -- Please check your units. Not clear to me how you can compare the volume of an LTCC circuit to the surface area, units are different.
For LTCC, I would recommend both an MoM simultator and a volume mesh simulator. If there is a lot of metal (like many ground shield layers), volume mesh is a good idea. Also, for sensitive circuits that come close to the edge of the circuit, volume mesh is a great way to include the effect of the nearby change of dielelctric from ceramic to air. Results from time domain volume meshers (we represent CST) that I have seen tend to be a lot cleaner than HFSS results, look at the very error sensitive current distributions, but both types should be useful. In general, I would think it is most useful to compare volume meshers vs. MoM, rather than HFSS vs. MoM.
I'm sure HFSS has a lot of success stories with LTCC, but you may not be aware of the numerous success stories for Sonnet in particular, and MoM in general. One other tool I can comment on is Momentum, and they have a number of nice success stories too.
One Sonnet success story is EPCOS (spin off of Siemens) in Munich . They came from a standing start about four years ago to beat two very well established Japanese LTCC vendors for a major sole-source Nokia contract in just 2 years. EPCOS succeeded because they used Sonnet. The two Japanese companies failed because they did not use Sonnet. I can send you a Prismark report on that fairly astounding situation. The quad band cell phone from Motorola that I have in my pocket uses a diplexer that was designed by making extensive use of Sonnet.
I'm sure there are a lot of other success stories from both MoM and volume mesh vendors. Who beats whom is most certainly not a clear answer.
My bottom line advice: Don't play golf with one club and don't do EM analysis with one tool. I think perhaps you might agree.
I am now at MTT-S, will not be able to reply frequently.