How to simulate semiconductor yield

Ben Taylor@bentaylordata

Synthetic yield• First step is to create X number of moving yield contributions or errors. For

this example we create 500 errors over 10,000 wafers. Some errors are sudden, others trend up over time. This plot shows 20 yield events starting after wafer #5,000

Staging behavior• A wafer never goes through a fab the same way. Many steps have multiple

tools and chambers that all have differences in processing. To simulate the fab environment we create a binary map of tools that were used by each wafer.

Simulating yield• To figure out the die loss you can add up the die loss contributions by the

contexts where the wafers ran for a total die loss estimate:

+ =

Can you figure out the source?• To figure out the die loss you can add up the die loss contributions by the

contexts where the wafers ran for a total die loss estimate:

&Given:

Find:

YX