How does solder reflow affect RF connectors?
EMP 2023 Electronics Manufacturing & Production Handbook
Manufacturing / Production Technology, Hardware & Services
By Janine Love, Samtec.
Solder reflow plays an important role in the success and performance of high-bandwidth RF connectors. Sometimes, when a high-bandwidth RF connector
is soldered together with an optimised PCB launch, the results can be unpredictable. It is important to investigate the root causes of solder reflow variation and analyse what techniques can deliver consistent performance across frequencies.
In a new white paper from Samtec, ‘Impacts of Solder Reflow on High Bandwidth RF Connectors,’ authors Michael Griesi (RF design & simulation engineering manager) and Chris Shelly (retired senior RF/SI modelling engineer) analyse the impact of the design choices for a specific push-on connector, its PCB, and the process. Using simulations and measurements, the team steps through its detailed development process to achieve the optimal design and better solder flow control.
The design team began with an initial two-piece contact, traditional design shown in the image. The ‘tombstoning’ effect that was found on some of the sample connectors can be quite clearly seen, where the connectors were tilting on the PCB. Snap on connectors such as this need to stay firmly on the board, with the centre contacting the board. The initial connector design was targeting 40 GHz bandwidth when soldered onto a PCB; however, simulations showed performance of less than 25 GHz.
As a first design step, the team experimented with the thickness of the gold plating and the insulator’s coefficient of expansion. Other topics investigated include solder wicking and pooling, PCB pad design, and tuning the solder reflow process. At the end of the design process, the final design had thinner gold plating, higher temperature insulators, and a single-piece swept contact. To further address performance concerns, the team added a chamfer to the bottom of the connector, a solder control tail on the PCB pad, adjusted the thermal profile, and other process adjustments.
The performance challenges experienced with this connector design process are not unique to this type of connector. At high frequencies, every little detail matters. To achieve optimal performance, it is important to have robust simulation capabilities and multiple troubleshooting and analysis tools. The challenges of solder reflow and the impact it has on performance extends to all high-bandwidth RF connectors. At Samtec, work continues in simulation, manufacturing process, PCB and connector design to continue to optimise performance in the field of solder reflow.
Further reading:
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...
Downstream demand, system reliability, and the expanding role of engineering-led distribution
Manufacturing / Production Technology, Hardware & Services
[Sponsored] As South Africa’s semiconductor demand continues to be shaped by downstream system deployment rather than upstream fabrication, the importance of engineering-led distribution will continue to grow.
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...
Non-destructive techniques for identifying defects in BGA joints – TDR, 2DX, and cross-section-SEM comparison
MyKay Tronics
Manufacturing / Production Technology, Hardware & Services
This whitepaper reports the results of a comparison of the following techniques: TDR, automatic X-ray inspection (AXI), transmission X-ray (2DX), cross-section/SEM, and Dye & Pry.
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.
Read more...