HFSS Setup: Advanced Tab

Select the Advanced tab of the HFSS Setup window to access the following settings.

Defeaturing

• Remove voids with an area smaller than <value>: simplifies meshing by removing small voids.
• Remove Floating/Inactive Signal Net Geometry: removes floating and inactive signal net geometry.

Model Resolution (IC Mode Only)

• Auto: automatically sets the model resolution.
• Length: allows you to manually set the model resolution.

Model Type: offers two types of models.

• General: offers standard mesh processing.
  • Use polygon defeaturing: removes very close points, points that do not contribute to the geometry of an edge (e.g., collinear), and very thin intrusions. When used with “unioning”, it can be helpful in healing geometry that is not snapped together.
    • Tolerance as a ratio of the data exent: tolerance value specified as a ratio of the overall data extent. This value must be very small.
    • Absolute distance: tolerance specified as an absolute value (e.g., 0.0001mm).
  Note:

  From the Vias area, vias may be modeled as a simple 'wirebond' or as a 3D ribbon or solid. The values specified in the analysis setup only apply to vias that do not have specific property overrides; all properties explicitly specified for a via take precedence over these values.

  • Point -to-edge and point-to-point snapping: snaps points to edges and points to points if they are within a minimum dimensional tolerance. This tolerance is based on geometry extents.
• IC [Beta]: optimizes geometry processing to simulate small, on-chip structures.
  • Auto: automatically sets the model resolution based on the design's geometry. Recommended for most designs.
  • Length: allows the user to manually set a resolution threshold. Features smaller than the entered value may be merged with nearby geometry, snapped, or removed entirely, especially if they don’t affect the overall structure or function of the design. Recommended if the design includes fine or critical details.

Vias

• Mesh as a 3D via vias are modeled using rectangles to form a 3D ribbon or solid.
  • Number of sides: number of sides to use when creating the 3D representation. If less than 3, the via is modeled as a flat ribbon.
  • Mesh for via plating – check the box to create a mesh around the plating percent specified in the Edit Padstack Definition window, resulting in a more accurate DC thickness value. A via that is not fully plated includes a void filled with the material defined in the surrounding air box (e.g., air). Zero plating is not recognized and is treated as fully plated.
• Via material default: when a material has not been specified in the padstack definition and there is no override in the properties for a via, then this is the material associated with the via mesh. It is initially set to copper.