Standard yield for wafer fab was defined as 80% of the wafers started made it to the end of the line.
Standard yield for electrical test was defined as 80% of the die on those wafers met electrical test requirements.
Standard yield for pressure test was defined as 80% of the electrically good die met sensitivity requirements.
0.8 x 0.8 x 0.8 ≈ 50% actual yield. They were happy with 80% of that when I started.
They were NOT happy with me explaining that to upper management...
Traditional management techniques always lead to information hiding, which is exactly what managers don’t want.
Why do they keep putting up with it?
Umm... Isn't Global Foundries looking for increased yields (or was that when they were still AMD)...??? ;-)
But then you'd need to move to either Silicon Valley in the land of Fruits and Nuts, or Dresden... You like German Bier, ja?
That’s a pretty crappy wafer yield in today’s fab. They get upset if it’s <95% electrical (no sensors) where I worked, back when I was in manufacturing. I was thrilled when I landed the job at R&D. Now it’s, “Huh? What is this ‘yield’ of which you speak?”