FMEA/PFMEA : What they never teach you in formal school

FMEA or Failure Mode Effects Analysis is an analytical procedure to identify and minimize risk factors in product and process designs. Whilst the FMEA methodology has been in use since the 1940's, the effectiveness of the procedure became really widespread after its adoption by the automotive industry in the late 1970's. The FMEA procedure is a preventative tool and hence must be performed prior to finalization of the design of the product and the manufacturing or service processes. Quality Assurance Standards such as ISO 9001 and TS 16949 emphasize the need for minimizing and /or eliminating risks in the design of products and processes, which has led to many organisations adopting the FMEA methodology as part of their D & D processes. This widespread use is encouraging, but equally important is the correct use of the procedure as otherwise the resultant documentation will not provide the required focus in the detection of risks. The use of robustness tools such as the Boundary diagram, Parameter diagram and the Interface matrix is essential in order to bring in the required discipline in the detection of risk factors. Experience shows that engineers often focus only on those aspects that they control directly and miss the causal factors, particularly the interfaces in the system, misuse of the product by the customer - either intentional or unintentional, and natural degradation, all of which cause the risks. In this article, the author explains how the robustness tools can be usefully applied in both the design and manufacturing design of products such as semiconductor packaging.