Defining Zones

Complete these steps to outline and define the new zone(s) using the Rigid-Flex Workflow.

Note:

The Rigid-Flex Workflow is only available after a design has been imported or created, and Multizone is chosen as the stackup's Type. Refer to the previous subsections of the Multizone Stackups and Rigid-Flex Bends.

Note:

Zones can an also be defined at the Layout Editor. Refer to Defining Zones at the Layout Editor.

From the Layout tab, click Rigid-Flex to open the Rigid-Flex Editor window.

Note:
As zones are created, they will appear in the Rigid-Flex Items area. Outline primitives that are not assigned to a zone will be located in the Unassigned zone boundaries section.

From the Rigid-Flex Editor window, define a zone by doing the following:
1. Right-click within the preview window and select Zones > any primitive drawing tool (e.g., Draw polygon).
1. Click within the preview window to draw a zone using the same method described in the HFSS 3D Layout Getting Started Guides for drawing primitives in the Layout Editor.
  
  Note:
  Click Reset at anytime to undo any changes and begin again.
  
  Once the zone is outlined, the Zone Primitive window opens.
2. From the Zone Primitive window, select the chosen zone designation on the drop-down menu (e.g., Primary).
3. Check the Fixed box, as appropriate. A fixed zone is used as reference during the bending process and cannot contain a bend.
4. Click OK to close the Zone Primitive window.

Floating Zones

Typically, each successive zone must abut another zone. Disconnected zones are added to the Floating zone boundaries section of the Rigid Flex Items area. To see this feature, repeat steps a-c to create the next zone (e.g., Zone1) but do not connect the new primitive to the Primary zone.

Zone1 Defined in Rigid-Flex Editor Window

Zone1 is added to the Floating zone boundaries section of the Rigid Flex Items area because it does not connect to the Primary (or any other) zone.

Note:

Zones must connect to the Primary (or any other zone) and cannot overlap one another. Model elements cannot extend into zones that do not share their placement layer. Invalid placement of zones results in error messages, which appear in the Rigid-Flex Items area, but will not necessarily halt rendering. If errors are not corrected, however, the final render may contain unexpected results.

Example of a Bad Zone Placement in Rigid-Flex Window

Using HFSS Model Extents to Modify Zones

Complete these steps to use HFSS Extents to modify the dielectric and airbox extents. Refer to HFSS 3D Model Extents.

To open the Set HFSS Model Extents window, do either of the following:
- From the Layout ribbon, click HFSS Extents.
- From the Project Manager window, expand the Project Tree (e.g., TestProject). Then right-click the active design (e.g., EMDesign1) and select HFSS Extents.
  The HFSS Bounds tab displays by default.
From the Extents area, select Zone Extents from the Type drop-down menus to affect the following changes:

Dielectric – the base-polygon is defined by the exact dimensions of the zone extents input by users on the Outline layer. Horizontal Padding is deactivated and any existing value in the Horizontal Padding field is ignored.
Airbox – creates a union of the zone extent polygons on the Outline layer and the user-entered value in the Horizontal Padding field to set airbox extents.

Using the Implied Regions to Assign Zones

The Unassigned zone boundaries section of the Rigid-Flex Items area includes all primitives that are not assigned to a zone. The primitives that can be assigned to a zone are implied_region(s).

Implied Regions in Rigid-Flex Editor Window

Double-click any implied_region to open the Zone Primitive window. Then repeat step c to assign the primitive to a zone (e.g., Zone2).

All Zones Valid

Note:

Depending on whether the unassigned primitives are connected, there could be multiple implied_regions in the Unassigned zone boundaries section.

Implied Regions in Rigid-Flex Editor Window

Changing the Zone Order

While creating a rigid-flex design, only a single zone stackup will be modeled in a location. If zones overlap, Zone Order is used to determine which zone the design will model and which zone(s) will be ignored. The zone with the most dominant position will take precedence. Complete these steps to change the Zone Order of any zone in the design.

Note:

Zone Order can an also be changed at the Layout Editor. Refer to Changing the Zone Order From the Layout Editor.

From the Rigid-Flex Editor window, select a zone.

The selected zone's parameters populate the Footprint tab.
From the Footprint tab, click inside the Zone Order Value field to select a new position from the drop-down menu (e.g., from 0, which has the highest priority in the hierarchy, to 1, 2, et cetera).

Reorienting the Model and Stretching Z

Reorient the model in the preview window using the same method of control common to the Layout Editor.

Rigid-Flex Editor Window

If appropriate, complete these steps to artificially scale Z values, so thin models have a 3D appearance.

Right-click in the preview window and select Stretch Z to open the Set Layer Thickness Scale Factor window.
Use the slider to set the scaling factor to any discrete value between 1 and 25.

Continue to Defining Rigid-Flex Bends.

Defining Zones at the Layout Editor

Complete these steps to outline and define zones from the Layout Editor.

From the Layout tab, select Outline on the Set Active Layers drop-down menu.

From the Layout tab, select any primitive drawing tool (e.g., Draw polygon).

Draw a zone over the design using the same method described in the HFSS 3D Layout Getting Started Guides for drawing a primitive.
Repeat steps 2-3 for each zone, keeping in mind that each successive zone must abut another zone. No zone can be floating.
Select a zone. From the Properties window, select the chosen zone designation on the Name Value field's drop-down menu.
Once the primitive is assigned to a zone, the Is Fixed and Zone Order rows appear. If chosen, do either or both of the following:
- Check the box in the Is Fixed Value field to use the zone as a reference during the bending process. A fixed zone cannot contain a bend.
- Select a new Zone Order from the drop-down menu in the Zone Order Value field. Refer to Defining Zones.
Repeat steps 5-6 for each zone.

Changing the Zone Order From the Layout Editor

Complete these steps to change Zone Order from the Layout Editor.

From the Layout Editor, select a zone.

The selected zone's parameters populate the Properties window.
From the Properties window, click inside the Zone Order Value field to select a new position from the drop-down menu (e.g., from 0, which has the highest priority in the heiarchy, to 1, 2, et cetera).

Continue to Defining Rigid-Flex Bends.

Related Topics:

HFSS 3D Model Extents