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Understanding 'stop' layers for Layout XL connectivity extraction

Lynks

I'm using ICADV12.1-64b.500.6 with a technology file I'm building from scratch for a experimental process and I'm trying to understand how 'stop' layers work.

I attached the following example:

LayerA = non-filled layer in the attached picture
LayerB = filled layer in the attached picture

(LayerAStop 10001 (LayerA 'not LayerB))
(validLayers (LayerAStop)) 

When I run diagnostics on my constraint group, I see LayerA is stopped by LayerB, so I believe the technology file is written correctly.

So my thinking is when I have a layout as shown in the attachment, Layout XL will extract LayerA until there is an overlap with LayerB and therefore the layout should be interpretted as an open circuit between pin A and pin B. However, the extractor still sees this as a short as you can see from the error, even after running the extractor again.

Is my understanding incorrect? How can I have Layout XL understand that any region where LayerB overlaps with LayerA should be an open circuit? 

  • Update:

    LayerB's function under the layerRules() was mistakenly set to 'cut'. I set the function to 'metal' (eventhough in reality it's not really the case), and the extractor correctly identified where to 'stop' when LayerB overlapped and I no longer see a shortcut between pin A and pin B.

    Looking at the different functions listed in the Virtuoso Technology Data ASCII Files Reference, I could not find a section where the functions are defined... some I can probably guess like metal, nwell, ndiff... but there isn't a clear definition of each function and how each would affect the extractor. As someone putting together a tech file from scratch, this would be useful information.

    Is there somewhere in the documentation that explains this?

     

  •  I'm not sure it is documented that way - it lists the allowed functions, but doesn't explain what they mean (this is in the functions section of the Layer Rules section of the Technology File Layer Attributes in the Virtuoso Technology Data ASCII Files Reference manual). There is a little bit of information about some of them in that part of the manual (try searching for "tsv" in cdnshelp to find it), but if you want more you should request this to be added via customer support.

    Knd Regards,

    Andrew.

     

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