This video is taken from the FDE Learning Track on Ansys Innovation Courses.
In this unit, we will set up the simulation based on our example device, a SOI rib waveguide.
In this example, we will use 2 materials, silicon and glass.
We can open the material database and check that both materials are already present.
Note it is possible to add new materials if needed, by clicking the “add” button and
selecting the appropriate material model.
We will first add the glass substrate using a rectangle primitive.
We can then set its dimensions in the “Geometry” tab, and select the material in the “Material”
We will rename this object and call it “SiO2”.
We will use another rectangle primitive for the silicon waveguide.
We set its dimensions to 500nm x span and 220nm y span.
The z dimension is not important as this simulation will be setup to assume that Z is the direction
Now we can set the material to Silicon and rename it “Si”.
Note we can use import options and predefined objects from the library to set up complex
Once the structure is defined, we can add the “Eigenmode solver” from the “simulation”
The background index is set to 1, and the dimensions are set so the FDE solver is placed
over the cross section of the structure.
The boundary conditions are set
Finally, we add a mesh override region from the same “simulation” button.
The geometry of the mesh override will be based on the Si object.
We will start with a fairly coarse mesh (for instance, 20nm in x and y).