Method for determining deficient processes and deficient processing stations

摘要

A method determines the deficient processes and deficient processing stations in the manufacture of a product fabricated by lots through a plurality of processes performed by a plurality of processing stations. From a plurality of lots, the good lots are distinguished from the bad lots. By using the process history of each good and bad lot, a good lot ratio and a bad lot ratio that are respectively produced by each process performed by one of the processing stations are calculated. The processes/processing stations are arranged according to a decreasing order of their bad lot ratios. The most probable deficient processes/processing stations are those which are arranged at the top of the arranged order.