Tilted CT Enhances X-ray Component Inspection for Flat and High-Density Elements

Nikon Corporation's Industrial Metrology Business Unit has unveiled a groundbreaking X-ray computed laminography (CL) technique, Tilted CT, designed to revolutionize non-destructive inspections using its computed tomography (CT) systems. This innovative method significantly enhances voxel resolution, making it ideal for examining flat, high aspect ratio components, and is a game-changer for quality control, providing clearer imaging for a wide range of samples.

Conventional 3D CT faces limitations when inspecting flat components, especially when the area of interest is concentrated in the center. The issue arises because the axis of rotation is at a 90° angle to the X-ray beam, preventing closer positioning of the component to the source for increased magnification and resolution. Tilted CT brilliantly circumvents this problem by allowing for an axis of rotation adjustment of up to 30°, enabling a full rotation beneath the X-ray source. This not only magnifies critical areas but also yields sharper images in significantly reduced scan times.

Tilted CT excels in various applications, from examining printed circuit board assemblies to probe cards used in automated wafer testing. In a comparative test, a scan that previously took over 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 standout feature of this technique is its ability to eliminate artifacts caused by high-density features in specimens, which often obscure low X-ray attenuation areas. By tilting the axis of rotation, high-attenuation areas can be strategically positioned to rotate beneath or above lower-density areas, exposing them clearly for inspection.

This capability is especially valuable when inspecting additively manufactured metal parts while they are still attached to their support plates. Tilted CT can scan components in their entirety, including the lower portion, by tilting the whole structure to match the dense build plate's rotation angle with the X-ray cone beam.

Tilted CT is compatible with Nikon's XT H 225, XT H 225 ST 2x, and large-envelope M2 X-ray CT systems. Nikon remains dedicated to pushing the boundaries of technology, aiming to deliver unrivaled imaging capabilities and expand the horizons of quality control. Tilted CT, along with several other recently introduced X-ray data acquisition methods and reconstruction algorithms, underscores this commitment to innovation.