Extending the measurement capabilities of 3D X-ray microscopy to dimensional metrology

Abstract

In the industry of manufactured and assembled devices, the miniaturization and integration of small components with feature sizes on the order of 10 mm or smaller leads to new demands for inspection measurement systems. There are requirements for higher levels of resolution, precision, and accuracy, ideally with technologies that measure internal features and avoid causing damage to the original device. Three-dimensional (3D) techniques such as X-ray computed tomography (CT) may be used to non-destructively inspect internal geometries, or features, that are difficult to reach (or impracticable to access) with tactile probes. Traditional CT systems are, however, limited in resolution and achievable measurement accuracy. One alternative would be to use higher resolution instruments such as 3D X-ray microscopes and expand their measurement capabilities to the field of high precision metrology. This paper demonstrates how to perform non-destructive inspection in small-scale volumes, using a field-of-view (FOV) of about 5 mm diameter, and achieve dimensional measurements that are highly repeatable and accurate (with deviations from calibrated data within the ±1 μm range). This capability is relevant for the electronic industry, e.g., for measurements of camera modules or injection molded connectors, and for manufacturing highly efficient components, e.g., fuel spraying injectors and additive manufactured components with small internal features.