Ooh, I was in semiconductor manufacturing too! As a junior ion implant engineer, I was looking into yield problems. Some of the tests were flaky and I traced the issue back to one of the transistors not delivering enough current. Great, we know how to fix that! More arsenic! I proposed a small scale experiment, those wafers tested great, and we started rolling out the process change. Those wafers tested great too.
Until we got word back from packaging post test. Every single die failed for excessive current draw. Several hundreds of thousands of dollars worth of scrap. I was correct, but I wasn’t deeply correct.
What surprises me in retrospect is that everybody signed off on this. It’s not like we didn’t have processes, I just somehow managed to talk a bunch of people who should have known better into doing it anyway.
Until we got word back from packaging post test. Every single die failed for excessive current draw. Several hundreds of thousands of dollars worth of scrap. I was correct, but I wasn’t deeply correct.
What surprises me in retrospect is that everybody signed off on this. It’s not like we didn’t have processes, I just somehow managed to talk a bunch of people who should have known better into doing it anyway.