Integration of RF shielding is a critical element in a widening variety of product designs, especially the mobile handheld devices that have become a ubiquitous part of our daily lives. As these products are getting smaller, more complex, and are offering higher performance features, the integration of RF shielding has become more challenging.
For example, longer shields (over 30mm) can exhibit a gap between the shield and the PCB. This can be due to a combination of coplanarity issues with the PCB and/or the RF shield itself. It can also result from warping of the PCB during production line assembly and soldering, in which case, the problem does not become apparent until after initial assembly.
The extra thin PCB materials, denser circuitry and higher frequency signals in new-generation devices are all combining to make these shield assembly problems a critical issue.
If gaps between shielding and PCB substrates are not addressed, it can lead to signal leakage that reduces the effectiveness of the shielding and degrades product performance, as well as mechanical stability problems that can cause hard field failures of the devices.
Solder-bearing RF shields address these problems before they can occur by incorporating a precise amount of solder onto the RF shields during their fabrication. This approach creates parts that are ready for placement and soldering, without the need for secondary dipping or other solder/flux application steps and which can deliver 100% solderability results while streamlining the production process. The bottom line outcome has been a significant increase in production yields and product reliability.
