Advanced RF packaging technology trends, from GSM to 5G

An article by Stéphane Elisabeth, System Plus Consulting, for Chip Scale Review – The consumer market today is one of the most innovative sectors in the industry. Indeed, in 2019, 5G mobile phone shipments have started and should represent ~30% of the market by the end of 2025. In this regard, connectivity has a very high value in the design of the phone. Several standards have been integrated into smartphones over the years, from Global System for Mobile Communications (GSM) to the more recent 4G Long Term Evolution (LTE) Advanced. These standards bring more challenges to smartphone designers who have to integrate the related components. Than ks to advanced packaging technology, these challenges have been overcome, providing the latest communication experience to the world. In this article, we will review the technology drivers and the state of the market, as well as the latest advances in ter ms of radio frequency (RF) packaging.

In the smartphone market, several RF suppliers share the total revenue. The evolution of the market, as estimated by Yole Développement, shows an increase in growth of 5G technology from 2019 onward. The growth will mainly be led by Sub-6 technology with the introduction of a new frequency band or by the reuse of 4G frequency bands. The “core” market, 2G and 3G, is expected to continue the use of traditional packaging, namely, land grid array (LGA). 4G and 5G technologies are expected to require new developments in order to enable adequate integration in the smartphone. This is currently opening the market to advanced packaging technology relying on system-in-package (SiP).

Besides the air standard, the integration technology will also split the supplier market. As shown in Figure 1, in 2018 the total market reached $15 Billion with more than 25% held by Murata. The company is currently leader of the market thanks to its largest portfolio (modules and discretes). To maintain their position, the rest of the leading companies are putting all their cards on 5G development and 4G integration. This will come through three main approaches. The first is the development of new components that integrate several functionalities in a small area. The second is to rely on the technology itself to implement the new standard. Finally, the third approach is to develop new packaging technology allowing the implementation of the front end close to the antennas. Usually, innovation in packaging comes after innovation in the implemented technology, but the opposite could well be seen today.

Packaging technologies: standard to advanced

Included with the several technologies that are under development to filter or amplif y the signal, traditional packaging, such as LGA, is widely adopted to implement the new components. But in order to improve the form factor along with the performance of the devices, new packaging technology, such as double-side ball grid array (BGA), has been developed. In this way, the packaging has enabled the implementation of the multimode multiband power amplifier module as well as enabled the innovation of the implemented technology… Full article