# Creating a Planar Multilayer Substrate

Create a planar multilayer substrate using the properties method that contains two layers. Layer 1 is set to substrate2 and Layer2 is set to substrate1. The second layer has a PEC ground plane.

myProp = myProject.Contents.SolutionSettings.GroundPlane:GetProperties()
myProp.DefinitionMethod = cf.Enums.GroundPlaneDefinitionMethodEnum.MultilayerSubstrate
myProp.ZValue = "0.0"
myProp.Layers[1].Thickness = "0.351"
myProp.Layers[1].Medium = myDiel2
myProp.Layers[2] = {}
myProp.Layers[2].Thickness = "0.2"
myProp.Layers[2].Medium = myDiel1
myProp.Layers[1].GroundBottom = cf.Enums.GroundBottomTypeEnum.None
myProp.Layers[2].GroundBottom = cf.Enums.GroundBottomTypeEnum.PEC
myProject.Contents.SolutionSettings.GroundPlane:SetProperties(myProp)

1. Since we want to know the properties for a ground plane, search for GroundPlane (object) in the Help1.
2. In the Help, under GroundPlane > Method List, note the following:
GetProperties ()
3. Use GetProperties() method to obtain the properties of a ground plane:
GroundPlane:GetProperties()
4. Determine the syntax to prepend to GroundPlane:
1. In the Help, under GroundPlane > Usage locations, note the following:
SolutionSettings object has property GroundPlane2.
2. Click SolutionSettings.
3. In the Help, under SolutionSettings > Usage locations, note the following:
ModelContents object has property SolutionSettings.
4. Click ModelContents.
5. In the Help, under ModelContents > Usage locations, note the following:
Model object has property Contents
Since we know that Model is the one of the top levels in the model tree, the result is then:
Contents.SolutionSettings.GroundPlane:GetProperties()
6. Since the project is the highest level, we prepend our reference to the project:
myProp = myProject.Contents.SolutionSettings.GroundPlane:GetProperties()
5. Set the ground plane type to planar multilayer substrate:
1. In the Help, click on the link in GroundPlane > Property List > DefinitionMethod > (Read/Write GroundPlaneDefinitionMethodEnum).
2. In the Help, under GroundPlaneDefinitionMethodEnum, note the option:
MultilayerSubstrate
The result is then:
myProp.DefinitionMethod = cf.Enums.GroundPlaneDefinitionMethodEnum.MultilayerSubstrate
6. Next we want to specify the two layers:
1. In the Help, under GroundPlane > Property List, note the properties of interest that still need to be specified:
Layers
ZValue
2. For this example, layer 1 is located at Z = 0.
myProp.ZValue = "0.0"
7. To specify the layers, search for PlanarSubstrate (object) in the Help.
1. In the Help, under PlanarSubstrate > Property List, note the following properties of interest:
GroundBottom
Medium
Thickness
2. The result is then:
myProp.Layers[1].Thickness = "0.351"
myProp.Layers[1].Medium = myDiel2
myProp.Layers[2] = {}
myProp.Layers[2].Thickness = "0.2"
myProp.Layers[2].Medium = myDiel1
3. To specify the PEC ground plane below the layers, under Property List > GroundBottomTypeEnum.
4. The result is then:
myProp.Layers[1].GroundBottom = cf.Enums.GroundBottomTypeEnum.None
myProp.Layers[2].GroundBottom = cf.Enums.GroundBottomTypeEnum.PEC
8. Update myProp with its new properties using SetProperties ():
application.Project.Contents.SolutionSettings.GroundPlane:SetProperties(myProp)
1 The API is available in the Feko Scripting and API Reference Guide (PDF) or Feko WebHelp.
2 The part that is prepended to the method, maps to the CADFEKO model tree structure.