Hello Damian,
I guess my explanations were not good enough: the simulation occurs in the free space. I am working with an Input field (Gaussian modulated CW; propagation direction +z; polarization linear Ey), a wafer (4×4; material: air (so, free space)) and two observation points (reflected and transmited). So, as it is free space, no Ez component should appear (only Ey, and Hx). But, when I visulize both observation points I get an electric field with Ex, Ey and Ez components. What it should not be because the propagation direction is perpendicular to the polarization one.
Thanks a lot!
PD: simulation is in 3D. I attach both files, the design and the analysis ones.