RMX3000: tilted inline CT for power electronics solder joint inspection

Royma offers the RMX3000 for power electronics solder joint inspection on high-volume inverter and power-module lines. The machine tilts its X-ray beam up to ±70° and reconstructs a 3D computed tomography (CT) image at the line, with a spatial resolution of 1.5 µm. Overlapping solder layers and stacked components on a dense board are seen separately, not merged into one flat projection.

The RMX3000 is a 3D microfocus tilted inline CT machine. It combines tilted 2D X-ray and CT inspection in one station. Its open, self-calibrating X-ray tube runs from 10 to 160 kV at a target power of 80 W. A flat-panel detector with 1536 × 1536 pixels records at 40 frames per second. The five-axis motion platform tilts the part up to ±70° and rotates it through 360°.

• Boards and assemblies up to 510 × 510 mm and 20 kg
• Geometric magnification up to 2,000× and system magnification up to 10,000×
• Fully automatic scanning and material handling
• Industry-specific detection algorithms that analyse each scan and flag failures automatically

Tilted CT separates what a top-down image overlaps

A flat top-down X-ray image projects every layer of an assembly onto one picture. On a power-electronics board, the solder under a component, the vias beneath it and the parts on the opposite side all fall into the same image. A void can hide behind a via, and a bridge can look like an overlap.

The RMX3000 views the board at an angle and reconstructs the region of interest in 3D. Solder layers, terminations and the structures behind them appear as separate slices. Air bubbles in solder joints, faulty capacitor and chip connections, and voids inside sealed components become measurable. The image above shows such a slice: voids in the solder under a large thermal pad and along the terminals of a neighbouring component.

“Power-electronics boards stack a lot of copper and solder into a small area,” says Gabor Szabo, Sales Director Europe at Royma Europe. “With the RMX3000 our customers see each solder layer on its own, at the line, and the software flags the joint that needs attention.”

Inline inspection for lines above a million units a year

Many new SMT and inverter lines are planned for annual volumes above one million units. At these volumes, inspection has to keep pace with the line rather than wait for samples to reach a laboratory. The RMX3000 is built for this setting. Loading, scanning and evaluation run automatically, and the detection algorithms return a decision on every board.

The same station also serves the process engineer. Bubble and void findings are recorded for each part, so trends in the reflow or assembly process become visible early. You decide on the basis of measured data, not on a single cross-section.

A high-precision mode for the critical few

Some features need a closer look than a fast inline scan can give. For these, the RMX3000 offers an optional High Precision CT mode. It takes samples up to 0.5 kg and 100 × 300 mm, with an average scan time of three minutes and a minimum voxel size of 2.5 µm. Overlapping, multi-level features that a fast scan cannot separate are resolved this way.

An optional Virtual Tomography mode displays the position, shape and size of internal details in 3D, without the surrounding structure in the way. Both modes run on the same machine. A suspect power module or gate-driver board can be examined in depth without moving it to a separate laboratory system.

“The fast tilted scan handles the volume, and the high-precision mode handles the parts where you need certainty,” says Szabo. “We show both on your own assemblies before you decide.”

The RMX3000 also covers related tasks in electronics, semiconductor packaging and batteries. More on typical inspection tasks is on the consumer electronics and automotive application pages and on the RMX3000 machine page.

Test scans available

Royma Europe offers test scans of your own inverter boards, power modules and assembled PCBs on the RMX3000. The scan shows which defects the tilted inline inspection decides automatically and where the high-precision mode adds information.

Gabor Szabo, Sales Director Europe, Royma Europe E-mail: gabor_szabo@roymatek.eu · Phone: +49 15156503316 www.roymatek.eu

About Royma: Royma Industrial CT develops and builds industrial X-ray and computed tomography systems, from 2D X-ray to horizontal, gantry, planar and inline CT. Manufacturers in battery, aerospace, semiconductor, casting, electronics and automotive use Royma systems to find defects, measure internal geometry and control production quality without destroying the part.