Quality assurance for micro manufacturing processes and primary-shaped micro components

Abstract

The development of robust and flexible manufacturing processes represents the major challenge to be overcome by industrially applicable micro production. For robustness and flexibility to be ensured also for micro dimensions, the manufacturing processes need to be controlled and continuously improved by means of a quality assurance system that is fast to respond, matches the requirements of production and is tailored to the micro-specific demands. Up to now, micro manufacturing processes have been characterized by a high degree of variability resulting from an increased number of significant influencing factors. Besides, the tolerance specifications of components with micro structures are in the micro and sub-micrometer range, requiring measuring methods to meet the highest demands in terms of accuracy. For micro manufacturing processes to be controlled on the basis of measured data, the increased significance of measuring uncertainty and measurement variation in relation to the required tolerances is to be taken into consideration. Measured data will always reflect the effect of both manufacturing and measurement variation, which may lead to wrong decisions being taken on the approval or rejection of components if the most rigid tolerance specifications need to be met. Therefore, the focus of this research document, generated as part of the Collaborative Research Center (SFB) 499, has been put on the continuous monitoring, control and separation of manufacturing and measurement variation by means of statistical methods and tools. The two ideas presented and discussed are a novel design for quality control charts and a control loop for the combination of statistical process control and statistical modeling, developed as part of the SFB 499. This article concludes by giving first results regarding the use of statistical tools in the field of micro manufacturing technology.