Google Pixel 9 reflects RF filter transition

With smartphone sales volumes stagnating, and an increase in competition from the emergence of new Chinese players, RF front-end suppliers are looking to reduce costs to maintain their profitability while meeting performance requirements. One of the ways they are doing this is by integrating multiple functionalities into a smaller number of modules. The second way is by transitioning to more competitive, high-performance technologies, and here the filter market is the most dynamic.

When it comes to acoustic wave filters, BAW-type technologies have been dominating the MB/HB front-end while bulk SAW and TC-SAW technologies have a major share in low-band modules. Multilayer SAW technologies are gaining strong momentum as an alternative to static technologies, using a stacked layer substrate to boost RF filter performance.

Yole Group observed this transition to new technology in its report RF for 4G/5G Industry 2024. Today Yole Group’s analysts step back and present a special focus on the Google Pixel 9 smartphone. The teardown team at Yole Group opens the system and takes a deep dive into the technology. Have a coffee and take a few minutes to discover what’s inside…

This article is based on the impressive collection of RF electronic analyses from Yole Group including: RF Front-End Module Comparison 2024 – 5G NR/sub-6GHz. – RF Front-End Module for Mobile 2025 – Status of the RF Industry 2025 – SAW Filter Comparison – BAW Filter comparison… as well as the Consumer Teardown Tracks.

Multilayer surface acoustic wave (ML-SAW) filters are increasingly taking share in the industry, they exhibit high performances and an attractive cost.  Murata with its IHP, Qualcomm with the ultra-SAW, and Broadcom have pioneered this approach.

The trend towards using multilayer SAW filters is occurring in flagship smartphones like the Google Pixel 9. Yole Group conducts teardowns of various consumer products and has identified piezoelectric on insulator (POI) ML-SAW filters in the Google Pixel 9 smartphone supplied by Qorvo and Skyworks.

Qorvo announced its new design in June 2024 combining mid-high band PAMiD and Diversity functionalities into a single chip, which were previously delivered by two separate chips. This shrinks the surface area by around 35%, reducing the die size and saving space on the PCB.

Qorvo has applied its LRT technology on a POI substrate in Qorvo’s QM77178, while Skyworks used TC-SAW for low band frequencies, is also adopting POI to achieve the required performance in its SKY5-8111.

Qorvo’s MB/HB co-integrated PAMiD+Diversity chip achieves around double the BAW filter content in a smaller footprint than previous PAD generations. The Skyworks chip is a low-band LPAD and features multiple SAW filters, including one using POI technology.

On top of the silicon wafer, the filter comprises four layers: a trap-rich layer, silicon oxide, piezoelectric, and electrodes.

The main difference between the Qorvo and Skyworks chips is the difference of layer thickness specifically for the oxide and the piezoelectric layer. That difference could be explained by the frequency addressed by the two different devices.

Yole Group has identified more than one chip in its teardowns, indicating that Soitec can tailor this game changing technology depending on system requirements—such as by changing the thickness—to make the parameters suitable for the needs of the customer.

You will find more details about these chips in the coming teardown analyses:

This year, Yole Group’s RF electronics team will continue to provide an extensive range of market and technology reports, reverse engineering and cost analyses.  Their in-depth research delves into this dynamic ecosystem, offering valuable insights into leading companies’ strategies and the latest advancements in RF technology.

Connect with Yole Group’s experts at Mobile World Congress 2025, for deeper insights into the industry. Schedule a meeting today.

Ihor Pershukov, PhD is a Technology & Cost Analyst, Radio Frequency at Yole Group.

With a deep expertise in semiconductor manufacturing, materials and radio frequency (RF) devices, Ihor oversees reverse engineering and costing analyses.

Collaborating closely with the laboratory team, he defines analysis objectives and establishes methodologies to unveil the structure of RF devices.

Prior to Yole Group, Ihor served as a researcher at CEA-Leti, concentrating on piezoelectric materials for acoustic devices’ manufacturing.

Ihor holds a master’s degree in Nanoscale Engineering from École Centrale de Lyon (France) and a master’s degree in Applied Physics and Nanomaterials from Taras Shevchenko National University of Kyiv (Ukraine). He has a PhD in Materials Science at École Centrale de Lyon.

Hassan Saleh, PhD is a Senior Technology and Market Analyst, Radio Frequency at Yole Group.

Hassan produces technology and market analyses covering the consumer and automotive markets.

Prior to Yole Group, Hassan worked at X-FAB (France) as manager of RF characterization and modeling, part of the R&D department, where he was responsible for the RF laboratory activities and the production of models of RF semiconductor devices and components. He was involved in the development of RF-SOI, GaN, and BiCMOS SiGe platforms for RF applications.

Hassan holds a master’s degree in micro-technologies and communication systems from INSA Rennes (France) and a Ph.D. in Physics from Aix-Marseille University (France).

This article has been developed in collaboration with Aymen Ghorbel, Technology & Market Analyst, Compound Semiconductors and Ezgi Dogmus, Director, Radio Frequency & Compound Semiconductors at Yole Group.

Source: www.yolegroup.com