Darrell,
K6 0.25um Yield Relative to K6 0.35um:
Let's assume the ramp of 0.25um is linear per week, ie: week 1 = 25 parts of 0.35um and 1 part of 0.25um, week 2 = 24 parts of 0.35um and 2 parts of 0.25um, etc., week 13 = 13 parts of 0.25um and 13 parts of 0.25um (claimed by Jerry --- 50-50).
With total of 1.5M shipped, let's say 10% (claimed by Jerry again), 0.15M = 0.25um, and 1.35M = 0.35um.
Now, say 0.35um yield is 100% (very, and very unlikely), then yield of 0.25um is
0.15M / 1.35M * (162 / 68) * (13 + 1) / [(162 / 68) * (13 + 1) + (13 + 25)] = 5.2%,
in which 162 / 68 = ratio of die size.
If yield of 0.35um = 50%, then 0.25um = 2.6%.
If yield of 0.35um = 25%, then 0.25um = 1.3%.
John.
Reference: Message 3993180. |
