Does any oneknow how to draw grating figure on CST?

Hello all,
I want ot simulate nanostrip figures in CST. but i don't know how to draw this figure. I upload a picture with the structure what i want to draw? the left one is 3D view, the right one is the cross section.
Anyone could give me some suggestions?
Thanks,
Joy

Draw your rectangle with the layers you need. now draw bar near it than chamfer
it in two sides rotate it and copy this bar n times. then subtracts this bars from your
rectangle and you get it.
pl

Thank you very much. I will try that.. :)

just draw a unit cell and define the boundary conditions "periodic" in the certain direction.