Nikon Metrology introduce new X-ray CL technique for non-destructive inspection

Nikon’s Industrial Metrology Business Unit has introduced its new X-ray computed laminography (CL) technique, which can be used on its computed tomography (CT) systems. The new technique claims to help solve non-destructive inspection challenges. Additionally, Nikon believes the new method will improve quality control levels as it will produce clearer images of samples, no matter the shape.

Key information:

• Nikon has announced its new X-ray computed laminography (CL) technique.
• The method can be used with Nikon's computed tomography (CT) systems.
• According to its developers, the new technique hopes to solve non-destructive inspection challenges and improve quality control levels. 

Tilted CT is expected to improve vowel resolution during the examination of flat, high-aspect-ratio components. During the scanning of flat components, which may include a small area of interest in need of inspection, conventional 3D CT suffers from alleged limitations regarding resolution due to the axis of rotation of the item under investigation being at 90 degrees to the X-ray beam. This makes it unfeasible to position the component closer to the source to increase the magnification of the area of interest and improve resolution, as the sample would collide with the source.

CL data acquired using Tilted CT avoids this problem, as axis rotation is allowed to be adjusted by up to 30 degrees, meaning the sample can fully rotate underneath the X-ray source. Faster scan times, higher magnification and improved image clarity are achieved in examinations like printed circuit board assemblies or probe cards that can be used in automated wafer testing, for example. During one comparative test, a scan that previously took more than seven hours using an X-ray microscope was completed in less than an hour using Tilted CT on an SEMI S2/S8 compliant XT H 225 ST 2x system.

Another advantage of the new technique is its ability to allegedly eliminate artefacts caused by high-density features in specimen-obscuring areas where X-ray attenuation is lower. If an axis can be tilted during rotation, areas of high attenuation can be positioned, allowing them to rotate beneath or above a lower-density area of interest instead of in front of it. This could be valuable particularly when inspecting additively manufactured metal parts that are still attached to their support plate. Additionally, components can be scanned in their entirety (including the lower portion) by tilting the complete structure, allowing the dense build plate to rotate at the same angle as the X-ray cone beams, with the aim of eliminating obstruction.

Tilted CT can currently be used with Nikon’s XT H 225, XT H 225 ST 2x and large-envelope M2 X-ray CT systems.