[SOLVED] HFSS GDS import of layers with different data-types

[rpm4159]

Hello, it is clear how to specify the layer destination/color/thickness etc through a layer mapping file for Cadence to HFSS gds files. However, the layout Im looking to bring into HFSS includes layers of a different datatype that are critical and need to be mapped as well. For example I may need to map layers 64:0 and 64:16 and the layer mapping resources Ive seen only allow a single numerical value for the import #. Is there any information on how to add different datatypes to the layermap file? I'm asking if there's a manual way or through adding it to the map file but eventually I want to just script the entire process though one file if that makes it easier (layer map and tech/substrate data).

Thank you

 

[volker@muehlhaus]

You refer to the workflow from GDSII into HFSS 3D Layout Design using XML template, is that correct?
I have created such templates and agree that you can only map a single datatype (purpose) per metal layer.

In my opinion, the easiest solution is to create a new GDSII layer mapping file in Cadence export, so that all your required Cadence purposes are mapped to the same GDSII datatype. This customized GDSII file would then be for HFSS use only.

 

[rpm4159]

Thanks Volker for the reply. Usually I stream out of Cadence through XStream, that makes sense to create a layer map file on the stream out to change the datatype back to 0 and just choose a different layer. I'll try that.

 

[volker@muehlhaus]

I meant something different.

My assumption is that you import into HFSS 3D Layout Design, which is the layer-oriented layout editor, not the solid modeller. That enables a much more complete template than importing GDSII into the 3D solid modeller, and uses an XML template where you define the layered structure. However, each physical position (z position) in that layered structure can only have one single layer mapping (layer and datatype).

If you need different layers or purposes to map into the same stackup position (e.g. purpose drawing and filler) this is not possible, so you would stream out GDSII with a modified layer mapping.

~~~

You wrote that you want to map to an entirely different layer. That is certainly possible, but not useful in the layer-oriented HFSS 3D Layout Design workflow with XML template that I discussed above: each position in the layered stack has only one line where we can have one layernumber and datatype.

(The data below shows only the structure, data itself is not a meaningful technology)

 

[rpm4159]

Ah I should have been more specific. My interest is only with bringing my layouts into the solid modeler. It sounds like the layout oriented editor (when you mentioned the z position on the entire board can only have one material assignment) would not be able to have conformal layers where the Z position at different X and Y locations are different materials. Thank you though for the reply.

 

[volker@muehlhaus]

It sounds like the layout oriented editor would not be able to have conformal layers where the Z position at different X and Y locations are different materials.

That's correct.

The workflow using the layer-oriented workflow and XML template is much more efficient (more automated) and works fine for planarized technologies like "my" SiGe technologies. But if you need non-planar materials, that is not supported.

One exception that is actually supported in HFSS 3D Layout Design with XML template: you can place local dielectrics if these are "drawn" objects, such as local silicon etching. This can be included in XML technology.

But it seems you need to use the solid modeller GDS workflow, although is rather limited regarding technology setup automation. Good luck!