Measuring and characterizing opaque multilayer metal film stacks on product wafers

摘要

The need to improve yield and avoid process errors has been a part of semiconductor manufacturing since the first integrated circuit was made. According to Jack Kilby, a coinventor of the IC, in the early 1960s a respectable yield on a single transistor was 10 or 20%. Today, wafers containing hundreds of ICs, each having 20 million transistors, can be manufactured with yields exceeding 90%. This remarkable improvement in yield was made possible by concurrent advances in both process technology and metrology.