Fault Tolerance and Yield

Most chips on a silicon wafer are thrown away after failing quality-control tests due to fabrication variations. Some of these `fatal' variations can be seen as extreme cases of the variations between chips which do reach the market. If it proves to be possible to evolve circuits which tolerate unusually wide semiconductor variations, then the quality control of the chips to be used could be relaxed according the attained operational envelope, resulting in increased yield. This is speculation.

Similarly, some defects which develop during a chip's lifetime may fall within an evolved circuit's operational envelope, giving some degree of fault tolerance. [10] showed that some fault tolerance requirements can be explicitly included into the operational envelope specification as the goal of evolution.