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How to remove the antenna effect on top metal??

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Full Member level 3
Dec 10, 2014
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The link to an old post regarding the removal of antenna effect in a design is quoted. In a reply by randyest to the post , it is told to connect to top metal layer to avoid the effect. What if I have antenna violations in the top metal layer?? How can I solve the issue??

Ideally It doesn't matter whether you are jogging Antenna affected Metal layer to Top or Bottom Metal Layer, Ultimately total area of that Metal layer which affected should be less than Area which causes Violation.
If you jog to upper metal layer area drastically decreases(only which is going towards Input gate is calculated as Metal area) based on where you jogged so its preferred(If you jog to lower metal again metal area of two pieces is summed up).Since Upper metal layer is manufactured late bye the time you dont have antenna effect as its caused during metal deposition and etching process.

One more easy way if you dont find track jog is,Find the input gate which affected,insert antenna diode near to it and connect them.
You can connect any part of that Net affected to Antenna diode towards input gate.
If you are connecting towards output gate, you need to check Metal layers. Ex: if M5 is affected, you are connecting that net to antenna diode towards output gate, check Net is moving below M5 in the path the its fine. If its moving above M5 at any point then path ll break so again you ll end up with violation.

I think i have provided full info.
Two Options are there.

1. Reduce the Higher layer metal area, which means change it to different track.
2. Add the reverse-bias diode at the gate.

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