Determining C_ij

Cij is the fraction of defects of defect type j that appear as faults of fault type i.  Assume that defect type j corresponds to a broken wirebond and fault type i is a open circuit.  Consider a die wirebonded to the center of a board ...

1. Break wirebond #1.
2. Does the the open circuit test detect the problem? (if the wirebond was one of many grounds, the test may not detect the problem!).
3. Repeat steps 1 and 2 for all the wirebonds.

Assuming all wirebonds on the chip are equally likely to be defective (broken).

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