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Design and Characteristics of Micro-focus X-ray Source Having Sealed X-ray Tube with Transmissive Target on Diamond Window and Its Use for Industrial Non-Destructive Inspection

Electronic devices such as medical instruments implanted in the human body and Electronic Control Units (ECUs) in automobiles or airplanes have a large impact on human life. The electronic circuits in these devices require highly reliable operation. X-ray non-destructive inspection has recently been in strong demand as one way to help ensure high reliability. Companies that use high-density packages for micrometer-scale circuits or lithium ion batteries require high speed and high magnification inspection of all parts. Our company has developed a new X-ray source supporting these requirements. Our X-ray source has a sealed tube with a transmissive target on a diamond window that offers advantages over X-ray sources having a sealed tube with a reflective target. The X-ray source provides high power X-ray with no anode degradation and a longer shelf life. In this paper, we will summarize X-ray source classification relevant to electronic device inspection and will detail X-ray source performance requirements and challenges. We will also elaborate on technologies employed in our newly developed X-ray source including X-ray tube design implementations for, (1) high power X-ray, high resolution and high magnification simultaneously, (2) reduced system downtime for automated X-ray inspection system, and (3) reduced X-ray dose utilizing pulsed X-ray emission mode for protection of sensitive electronic device.


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