The EtchedFilmThickness will be used to define the thickness of the substrate layer.
To add the substrate layer to the layout, follow these steps:
| Step | Action |
| 1 | Click on the Add Substrate layers button, next to the Waveguide button of Figure 5. Â Double click on the new item in the list to get the Substrate Region dialog box |
| 2 | Click Add to get the Layers dialog box, and enter EtchedFilmThickness for the Thickness. |
| 3 | Set the material to Film from the combo box. |
| 4 | leave both dialog boxes by Clicking OK.
The refractive index view will now show the film of thickness 0.4 microns covering all the substrate. |
Figure 6: Ridge Waveguide
Note that the Substrate Layer is available in OptiBPM as well. Use this feature for designing ridge waveguides or other waveguides that have a multilayer film on the wafer between waveguides. The Layout in OptiBPM Designer will show the location of the ridges, and is the appropriate picture for preparing the layout masks.