2.2 CHANGE-CONTROL POLICIES OF MAJOR PART MANUFACTURERS
In an effort to evaluate the uniformity of change-control policies in industry, a survey of the top semiconductor manufacturers was performed. It was found that specific change-control board policies vary widely from one company to the next. Many have policies detailing the amount of testing that needs to be done to propose a change to the board, and many have policies on how quickly the changes are phased into production. For example, ON Semiconductor uses a simple chronological system. First, an initial product change notification is issued. After this, the final product change notification confirms the change’s implementation (ON Semiconductor, 2010).
Samsung has a three-tiered classification system (Samsung, 2002). The most drastic changes, such as changes in production location, are classified as Class A and require full requalification data. More moderate Class B changes, such as changes in testing procedures, require only “semi-qualification” data. Finally, less significant Class C changes, such as changes to packaging used for shipment or marking on components, require only a simple data review.
National Semiconductor goes even further, with a four-tiered classification system (National Semiconductor, 2002b). Level 1 changes are any changes to a process, material, method, or part design that do not represent a fundamental change to the process technique, material, or part functionality. These changes require no formal ...