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Do foundries ever put multiple chip designs on a single wafer? The idea is to increase yields by putting the bigger chips in the middle, and smaller chips arou
by erichocean 6y ago
Do foundries ever put multiple chip designs on a single wafer?
The idea is to increase yields by putting the bigger chips in the middle, and smaller chips around the edges—perhaps for different customers entirely…
- omgtehlion 6y agoYou need repeating pattern due to how steppers work. Theoretically you can have different chips, but they will be distributed evenly. And "yield" in this case is not how many chips can be placed on a wafer, but how many of them will not have defects in critical areas.
- erichocean 6y agoThanks!
- andoriyu 6y agoPlus customers pay per wafer, so you have put different customers entirely. TSMC themselves don't care how many chips gets made from a single wafer.
- atq2119 6y agoThere are foundries that do multi-project wafer runs for very small customers. It's not motivated by yields, though, but by sharing fixed costs with other customers if you don't really want to do mass production.
- deleted 6y ago[deleted]