5 Replies Latest reply on Jun 1, 2012 1:09 PM by chris_balcom

    auto metal fill

    wang.cupid

      Hi folks,

       

      I am working on a 28nm project, which requires auto metal fill for our chip. After googling, I know that Calibre is able to do auto metal fill. But I have not found any commands or scirpts concerning how to do this. Can you give me a hint or any comments about using Calibre. Plus, Calibre SmartFill can do this as well, but we have no such product.

       

      Thanks a lot.

        • 1. Re: auto metal fill
          chris_balcom

          Hi Wang,

           

          I'm not an expert with fill related issues but I did find some information that you may find helpful. I'd like to know if it helps or not, please let me know:

           

          http://supportnet.mentor.com/docs/201204032/docs/htmldocs/mgchelp.htm#context=calbr_cmpanalyzer_user&tab=0&tag=10530&id=4

           

          I was talking with someone else about your post and they found this link that I found every interesting. It doesn't describe how to invoke the tool but the historical background related to fill requirements and mention of 28nm was very interesting to me:

           

          http://www.eetimes.com/design/eda-design/4237906/Density-Requirements-at-28-nm

           

          This trend in fill placement made more designers want to check the impact of the fill on the performance of their designs, and by around 65 nm, it became common for design teams to take control of the fill process themselves, using fill rule decks provided by the foundry. Although this shift in responsibility continued down to 45 nm, density was still a chip-level issue, to be solved at chip assembly or tape-out.

           

          The problem for the designer is that, with more and more constraints being applied to protect circuitry and ensure manufacturability, the steps that can be taken to achieve the desired density average are more limited. But that still doesn’t explain why, at 28 nm, fill now becomes the cell designer’s job.

          • 2. Re: auto metal fill
            wang.cupid

            Thank you, Chris.

             

            I cannot access the first link because of my support status. I am from a Canadian university, not industry. Maybe that is why the resources are not accessible to me. I read through your second link, which is very helpful.

             

            Do you have any suggestions or comments? Where can I possibley find these commands or technical documents?

             

            Thanks a lot.

            • 3. Re: auto metal fill
              chris_balcom

              Hi Wang,

               

              The university may have a special arrangement that should help. Whoever is in charge of downloading the Calibre versions for your system should also be able to download all the documentation (they are available separately for download) and then you could have access to the manual referenced earlier. It is called "Calibre CMPAnalyzer User's Manual" and the filename should be "calbr_cmpanalyzer_user.pdf".

               

              Best regards,

              -chris

              • 4. Re: auto metal fill
                wang.cupid

                Thanks a lot, Chris.

                 

                I found this manual, but it says only TSMC is supported. That is to say, we still cannot use it to do metal fill for our 28nm ST technology.

                 

                Wang

                • 5. Re: auto metal fill
                  chris_balcom

                  Hi Wang,

                   

                  Do you have a foundry related contact that you could ask for details about fill implementation for that process you're using? I'm getting the impression that you shouldn't have to start fresh and create everything yourself, but rather should be able to follow steps that the foundry has already established for your specific process.

                   

                  Please let me know what you find. I'm learning more than I expected about this flow as we discuss it.

                   

                  -chris