Automated X-ray Inspection for IGBT Power ModulesNovember 11, 2019 by Paul Shepard
Saki Corporation has introduced its 3D-CT automated X-ray inspection (AXI) system designed specifically for the inspection and measurement of insulated gate bipolar transistor (IGBT) power modules. The 3Xi-M200 AXI is built with the highly rigid and stable hardware required for inspection accuracy, yet is 20% lighter, with a 25% smaller footprint and an imaging speed that is increased by 30% over its predecessor.
The 3Xi-M200 joins Saki’s recently introduced 3Xi-M110 3D-CT AXI system for printed circuit board assemblies (PCBA) as part of its lineup of compact, lightweight, ultra-high-speed inline 3D-CT automated AXI systems. The 3Xi-M200 will be available in January 2020.
IGBT modules are semiconductor devices used in transportation systems such as railways and automobiles for controlling high voltages and large currents. High-accuracy image inspection of these modules is very difficult, even with X-rays, because they are usually sealed with a heat sink that has a thick complex structure with multiple layers of solder hidden in the heat sink.
Saki's unique powerful 200keV (kiloelectron volt) high-precision X-ray imaging and precision 3D reconstruction, using Saki’s planar computed tomography (PCT), provides clear images by penetrating through the heat sink’s multiple layers. This technology makes Saki’s IGBT X-ray inspection system the most powerful and capable on the market.
The 3Xi-M200 is equipped with a newly developed detector that enables high-sensitivity imaging while expanding the field of view (FOV) and updated 3D-CT reconstruction processing software. Inspection is optimized by linking the hardware and software together with an automated inspection algorithm that provides a much clearer and more reliable image with less noise.
The 3Xi-M200 is 1,400mm wide and weighs just 5,100kg, saving manufacturing floorspace and enabling easy installation and improved production-line operation. The platform handles board sizes of 50 x 140mm (W x L) to 360 x 330mm (W x L). For larger 360 x 510mm (W x L) boards, 2-step image capture is available. The machine’s cast iron frame maintains the rigidity needed for stable operation.
Extremely high positioning accuracy is achieved by optimizing motor power with a double motor-driven system equipped with a high-precision linear scale manufactured by Magnescale Co., Ltd. Saki’s original PCT technology algorithm has also been optimized to improve image capture speed by 30%, reducing production-line takt time.
“Saki will continue to leverage the accumulated elemental technologies of its 2D and 3D automated X-ray inspection machines to meet the needs of the market and our customers’ demands for increased process quality,” said Masahide Iino, director and head of the sales division of Saki Corporation.
“Saki’s conventional model BF-X2 AXI system is highly rated for the accurate image quality produced with its unique Planar CT technology, and it’s already being employed extensively by major IGBT module suppliers around the world. With the new 3Xi-M200, Saki has succeeded in further improving its inspection image accuracy, operational ease-of-use, and effectiveness as an inline system. It’s reduced weight and footprint, increased speed, rigid hardware platform, and imaging accuracy provide the high-precision, high-quality, fully automated inspection solution required for IGBT modules,” Iino concluded.