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MC test dependent on pass/fail of previous MC test

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Hello.

I am trying to create a 2 step test simulation for a Test Screen for customer sample units.  I want to a) tell production how many units to expect to test to generate a certain number of good sample units, and b) tell field engineers what percentage of units might fail due to temperature changes in the field.  And I want to do screening only at room temperature.

The first task is to take as-built silicon and predict the yield percentage based on room temperature results.  It may be only 60% yield, so there will be a large fall-out in the set of MC runs. (That is, there will not be a small set of bad devices that could easily be dealt with individually.)

Then I want to take just the passing MC runs and re-simulate them using the MC parameters at several temperatures to get a prediction of the yield of devices that passed room temp sims, but failed at other temps.  I expect a high yield / low fallout due to temp effects in my particular case. 

I can do this with a lot of post-processing, but I am asking if there is a way to simulate only the passing MC runs of test 1 in test 2 - essentially ignoring any MC run that was already a fail at room temp.

If this is possible, it seems like it would take 2 tests.  I have tried just running the same sims at room and other temps in corners, and then looking at the results across corners for each MC run, but I still have to find the specific room temp failures and somehow account for them in the yield calculations - which is post processing I can do, but would like to avoid.

Suggestions?  Is these even possible?

Thank you.


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