In modern high-density electronics, the most critical threats to reliability are often invisible. A microscopic solder defect, hidden beneath a complex BGA package or too subtle for the human eye, can lead to intermittent failures or catastrophic breakdowns in the field. This is why “good enough” visual inspection is no longer an option.
At Kingda, our commitment to a zero-defect standard is built upon a foundation of advanced inspection technologies. Today, we’ll take a deep dive into two of our most powerful tools—3D Automated Optical Inspection (AOI) and 3D X-ray Inspection—and explain how they allow us to see the unseen.
3D AOI: Seeing in Three Dimensions for Unmatched Surface Accuracy
Traditional 2D AOI can verify if a component is present, but it struggles with judging the quality of the solder joint itself. This is where 3D AOI provides a quantum leap in capability.
What it Does: Our in-line 3D AOI systems use advanced laser and camera technology to create a complete three-dimensional model of every single solder joint on a PCBA. Instead of just looking at a flat picture, it measures the height, shape, and volume of the solder with micron-level accuracy.
What Hidden Defects it Uncovers:
Insufficient Solder & Cold Joints: 2D AOI might see that solder is present, but 3D AOI can tell if the volume is too low to form a reliable connection.
Tombstoning: It instantly detects if a small component has lifted on one side, a defect known as “tombstoning.”
Coplanarity Issues: It can identify if a component’s leads are not sitting perfectly flat on the PCB pads before soldering, preventing future failures.
The Kingda Advantage:
By implementing 100% 3D AOI inspection after both solder paste printing (SPI) and reflow soldering, we create a data-driven process loop. This allows us to not only catch defects but to proactively identify and correct process deviations in real-time, ensuring the highest possible consistency and yield for your project.
X-Ray Inspection: The Power to See Through Components
For components like Ball Grid Arrays (BGAs), QFNs, and other bottom-terminated packages, the most critical solder joints are completely hidden from view. This is where X-ray inspection becomes indispensable.
What it Does: Our high-resolution 3D X-ray inspection systems pass controlled X-rays through the entire PCBA, generating a detailed image of the internal structures, particularly the solder connections hidden beneath the components.
What Hidden Defects it Uncovers:
- BGA Voids: It can detect and measure the percentage of voids (air bubbles) within a BGA solder ball. Excessive voiding can lead to poor thermal performance and joint cracking over time.
- Head-in-Pillow (HiP) Defects: This subtle defect, where the component lead and solder paste fail to fully merge, is a major cause of intermittent failures and is virtually impossible to detect without X-ray.
- Hidden Solder Bridges: It can instantly see if any of the hundreds or thousands of solder balls under a BGA have bridged together, causing a short circuit.
- Via Fill Verification: It can be used to verify the fill quality of plated through-holes in complex, high-layer count PCBs.
The Kingda Advantage:
We don’t just use X-ray for troubleshooting; it’s a core part of our quality assurance for any project involving BGA or other bottom-terminated components. Our AS9100D and ISO 13485 certified processes mandate rigorous X-ray inspection to ensure the absolute reliability required for the aerospace, medical, and automotive industries.
Conclusion: A Multi-Layered Approach to Quality
3D AOI and X-ray inspection are not mutually exclusive; they are complementary technologies that form the backbone of a modern, data-driven quality control system.
3D AOI is the guardian of surface-level perfection.
X-ray is the guardian of internal integrity.
By investing in and mastering both of these advanced inspection technologies, Kingda provides our clients with more than just a PCBA; we provide them with the confidence and peace of mind that their product is built to the highest possible standard of quality and reliability.
Don't Let Hidden Defects Compromise Your Product's Success
Are you developing a product where quality and reliability are non-negotiable? Partner with a manufacturer who has the vision to see the unseen.
Contact Kingda today to learn more about our advanced inspection capabilities.
