should mesh size smaller than the smallest feature in the design?

[PING HEParticipant]

Hi everyone:

Just got one question on the mesh size. I have some small feature in my design, typically around 5nm. Should the mesh size chosen smaller than the smallest feature size?

Thanks.

Ping

[Damian MarekParticipant]

Hi Ping,

The rule of thumb for FDTD simulations is creating a mesh that is:

wavelength/(10*n)

where n is the largest index of refraction. That being said you definitely want the mesh resolution to be fine enough that the details of your design are captured. If your feature is located in a small section of the simulation domain then a nonlinear mesh is a good method for keep computation time down.

Regards