Reflection and Transmission of Si (3D)


I am trying to obtain the reflection and transmission of a Si based thin film coated on a glass substrate. I am confused about the geometry tab and the boundary condition tab of FDTD Simulation Region. Please let me know what should be a good choice! I am attaching the file.

ZnO_Thin_Film_Optical_Properties_Si_3D.fsp (279.8 KB)


Please go to the following link and follow the instructions given there. All the necessary information are given in the link.


Hi @sbs019

Here are a few things to consider:

  1. Extend your substrate into PML in the -z direction:

  2. Plane wave source should not be cut by PML. This can cause edge effects:

  3. Since your structure in infinite along the x- and y-directions, you can set your boundaries along the x and y to be periodic. You can also simplify your structure to be 2D for faster simulations. Please visit the application example in the link below:

  4. If you are new to Lumerical, I strongly recommend you to take our free online course on FDTD:
    Lumerical University

Hope this was helpful.


Thank you for your response. I was looking into the plane waves -edge effect. I was trying to obtain the intensity (E) from the source result.

ZnO_Thin_Film_Optical_Properties_BK.fsp (406.7 KB)

In the example, given in the website, it looked like the one I am attaching below.

The result I obtained from my simulation doesn’t look near to this. Would you please help me with this?


Hi @sbs019

If you want to obtain the same plot, simply use a DFT monitor that covers the entire simulation region:

After running the simulations, visualize the E field and then select abs^2 from scalar operation.


Thank you for your reply. I was trying to run a file that is given as an example in the lumerical website. It looks like it is taking a very long time to simulate. Could you please check if this is right?

solar_silicon_pillar (1).fsp (316.3 KB)


Hi @sbs019

The simulation is 3D with periodic BCs, and it is expected that it will take long time to finish. You could also check the memory requirements from the check button. The link below has some details on how to choose your resource settings:
How to obtain the optimum FDTD resource configuration?

The time sounds about the same as in my machine. However simulation may finish earlier once it triggers the auto shutoff level.