For the latest generation of micro-fabricated devices that are currently being developed, no suitable 100% in-line production inspection equipment is available, simply because current inspection equipment expects planar processing while most of the devices are often highly 3D in nature e.g. for medical devices. This lack of automated process feedback makes it difficult to steer process development towards higher yields in micro-components and MEMS production.
Another visible problem is the need to document and record process data, even on the individual device level, with the degree of traceability as is required for example, for medical devices fabricated under ISO13485. Both factors in the end limit the possibility of reliable and cost effective manufacturing of MEMS and micro-components.