• bacon_pdp@lemmy.world
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    5 days ago

    There is a design, fab, test cycle involved with working out all bugs in a design in relation to a specific lithography manufacturing process.

    • lectricleopard@lemmy.world
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      5 days ago

      Rarely are full designs respun. That’s a huge waste of NRE cost. Lithography masks are millions of dollars.

      Devices are characterized and techniques are explored on mpw designs. Multiple Pattern Wafer. Many customers design a small test die, and they are stitched together to make a single wafer and then you’ll get a few dies for evaluation. This way the cost is shared between many customers and experiments.

      If even one mask (out of dozens) needs rework after a full design is getting fabbed, its considered a big error.