31 March 2021Manufacturing / Production Technology, Hardware & Services
Build the clearest understanding of electronics defects using top-down 2D, inclined-angle 2.5D, and full 3D X-ray inspection. Ever been to see a doctor for an X-ray and a CT scan? This is a common process that allows medical professionals to build a complete picture for diagnosis.
In the electronics world we have similar X-ray techniques for non-destructive failure analysis. A quick 2D X-ray inspection provides a good insight into signs of defective connections, and a 3D CT scan can verify the problem with the added benefits of more data, building the complete picture ready for diagnosis.
BGA (ball grid array) packages are commonly inspected non-destructively utilising X-rays. Each solder joint is an individual electrical connection. A good solder joint will be reasonably circular in shape and the size of the joints should be reasonably consistent throughout the device array.
Figure 2. Ball diameter measurements performed on a BGA device.
Figure 1 shows several different types of defects which may occur during the BGA assembly reflow process. 2D X-ray inspection is a great tool for quick analysis, and one type of analysis that can easily be performed is a ball diameter measurement (Figure 2). Here one can see that the ball on the bottom right is approximately 70 µm smaller in size than its neighbouring joints. This is the first sign that there is a potential problem with this connection.
Figure 3 is a 2.5D oblique-angle image of theses joints. This image builds our diagnosis further, as now we see another sign that this joint is not completely fused on one side. This is seen through a different greyscale displayed on the interface of this joint.
Having identified strong signs that there is potentially a defective connection, this can be verified further with a 3D CT scan. CT is a technique which captures several images from different angles and then uses reconstruction algorithms to create a 3D model. The results of this can be seen in Figure 4.
Figure 3. 2.5D oblique-angle view of the BGA solder joints.
It can clearly be seen that there is a difference in the ball shape highlighted with red arrows compared with surrounding balls. The image to the top right side shows the quality of ball wetting to the device interface. It is clearly seen that there is an interfacial difference compared to neighbouring joints.
Now that both 2D and 3D images have been analysed, there is enough data to build a complete picture and diagnose this BGA device. The solder joint is confirmed as ‘non-wet open’ and as a result this would have significant impact on its integrity, and ultimately the integrity of the BGA device and the product it ends up in.
Outscale your competition
Manufacturing / Production Technology, Hardware & Services
Attendees will be able to explore the benefits of AMD Kintex UltraScale+ Gen 2 FPGAs in high-performance Pro AV, test & measurement, industrial, and medical applications.
Read more...MTN SA Foundation drives youth pathways into the digital economy
Manufacturing / Production Technology, Hardware & Services
The MTN SA Foundation, in partnership with Helios Towers and Datacomb Development Hub, has launched the MTN–Helios Towers 12-month ICT Learnership Programme, a pathway that takes young South Africans from digital training into real workplace experience.
Read more...The impact of harsh environments and ionic contamination on post-reflow circuit assemblies MyKay Tronics
Manufacturing / Production Technology, Hardware & Services
There is well documented historical proof that post-reflow circuit assemblies, when subjected to harsh environments, are particularly vulnerable to failure mechanisms, but modern electronic assemblies are far more susceptible to this phenomenon.
Read more...Engineering copper grain structure for high-yield hybrid bonding in 3D packaging Testerion
Editor's Choice Manufacturing / Production Technology, Hardware & Services
The way copper grains are sized and distributed forms the metallurgical foundation of hybrid bonding, enabling lower bonding temperatures, greater reliability, and stable grain structures throughout integration.
Read more...Understanding solder dross: causes and control strategies Truth Electronic Manufacturing
Editor's Choice Manufacturing / Production Technology, Hardware & Services
Dross formation is an inevitable consequence of wave soldering. It occurs when molten solder comes into contact with oxygen, forming metal oxides that float on the surface of the solder bath. Over time, this oxidation byproduct accumulates and must be removed to maintain solder quality and process consistency.
Read more...Implications of using Pb-free solders on X-ray inspection of flip chips and BGAs MyKay Tronics
Manufacturing / Production Technology, Hardware & Services
With the move to Pb-free soldering, most of the attention has been paid to reflow temperatures, component compatibility, and reliability concerns, but the implications for inspection, particularly X-ray inspection, are equally important and often underestimated.
Read more...The causes of solder balls in robotic soldering
Manufacturing / Production Technology, Hardware & Services
Solder balls (also known as solder splatter) are a major concern in many production sites as they may potentially cause shorts, leading to long-term impacts on product reliability.
Read more...Material challenges for superconducting quantum chips
Manufacturing / Production Technology, Hardware & Services
To achieve the scalable and repeatable production of superconducting circuits for quantum technology products, players in the industry are leveraging semiconductor fabrication techniques.
While every effort has been made to ensure the accuracy of the information contained herein, the publisher and its agents cannot be held responsible for any errors contained, or any loss incurred as a result. Articles published do not necessarily reflect the views of the publishers. The editor reserves the right to alter or cut copy. Articles submitted are deemed to have been cleared for publication. Advertisements and company contact details are published as provided by the advertiser. Technews Publishing (Pty) Ltd cannot be held responsible for the accuracy or veracity of supplied material.
Figure 1. A range of defects that can occur during the BGA reflow process.
Figure 4. Multiple 3D rendered views of the BGA device.
printer friendly version