A Comparison of BAW & SAW Filter Technology for RF Front-Ends

In 2018, the market for RF front-end and connectivity was worth US $15 billion. According to Yole, this figure will reach US $26 billion by 2025, at a CAGR of 8%.

For many years, Band Acoustic Wave (BAW) filters have been the leading RF filter technology for high frequency bands in mobile communication. Last year, Murata released a new filter based on a TF-SAW technology, the Incredible High Performance (IHP) SAW filter. This technology allowed Murata to address multiple smartphone functions, including PAMiD and diversity receivers.

In 2018, the leader of this market was Murata, with a quarter of the market, mainly with its discrete filters. In this segment, more than 60% of the filters are based on SAW technology in 2020. SAW filters are based on the three main manufacturing processes: SAW, TC-SAW and TF-SAW.

In 2020, Qualcomm is challenging Murata with its own TF-SAW RF filter. With this announcement, the US company could dominate the market. Qualcomm is the only player with the full capability to supply the entire RF chain from the modem to the antenna. Regarding its filter activity, thanks to its acquisition of TDK-Epcos via RF360 joint venture, Qualcomm was able to provide SAW (Standard, TC-SAW) and BAW filters. Recently, Qualcomm has demonstrated its ability to provide TF SAW filters with higher performances than its own BAW filter in certain bands.

TF-SAW filter technology definitely disrupts the market and in performance directly competes with BAW filter. Murata has taken advantage of this technology to develop a large panel of customers and applications and reinforce its strategic market positioning. System Plus Consulting analyzed the Murata RF front-end module in a dedicated Murata IHP SAW Filter report.

With this technology choice, Murata is now able to enter the high frequency market, reaching Wi-Fi front-ends. The IHP SAW filter has shown results comparable to competing BAW filters in this field.

System Plus Consulting has also developed a new comparative report - SAW Filter Comparison 2020. This study is an impressive structural, process and cost review of key SAW filter technologies developed by leading companies as well as others. This comparison includes filters developed by leading players including Murata, Skyworks, Qorvo, Qualcomm, Taiyo Yuden, Kyocera as well as smaller companies such as Wisol, Tai-SAW, SAWNICS and Shoulder Electronics.

The company offers a complete study of 9 SAW filters which uses standard piezoelectric as substrate, 4 TC-SAW Filters which uses a thermo-compensated layer to avoid thermal drift and 1 TF-SAW filter which uses Lithium Tantalate on Silicon substrate. This analysis points out the direct relation between function and structure of those SAW filters.

System Plus Consulting’s team discloses the technical choices made by leading OEMs, from low to high-end products. Process flows for the 13 SAW technologies have been identified and deeply analyzed, allowing System Plus Consulting to reveal a relevant manufacturing cost comparison. Physical data for each component has been compared in terms of process flow, cost and integration to provide a large panel of technical and economic choices.

For example:
• Standard SAW technology from emerging Asian companies compared to leaders in the market
• TC and High-Performance SAW filters using oxide layers, air cavity and protective layer
• TF-SAW from Murata using ceramic/silicon wafer bonding to improve standard SAW technology
 This latest report from System Plus Consulting takes into account the China-US trade war and its direct impact on the smartphone industry, especially the RF filter market segment.

The report tries to answer the following questions:

  • Who is doing what? 
  • Who is leading the SAW filters industry?
  • What is the status of the competitive landscape? 
  • Which technology choices have been made by the companies? 
  • What are the benefits and the costs of each technology? 

Regarding pure SAW, several Asian companies are involved, like Wisol and Kyocera, explains System Plus Consulting in its comparative analysis. Wisol bought the SAW filter manufacturing capability from Samsung back in 2008. Since then, Wisol has developed a portfolio offering a broadband module from the single filter to FEMiDs exclusively based on the SAW filter. Wisol is currently working with Samsung.

TC-SAW technology is more complex and System Plus Consulting has identified four main players: Qorvo, Skyworks, Murata and Qualcomm. Skyworks and Qorvo made large investments 10 years ago to develop and offer innovative solutions focused on TC-SAW filters with complex packaging and high performance. Both companies currently have solutions available in the market now and would like to keep their positions as market leaders. Qorvo is now also developing a TF-SAW based solution.

The other two companies have now also introduced TF-SAW technology into their portfolio, Murata in 2019 and Qualcomm in 2020.
SAW filters along with passives components are the primary technology developed by Murata. With several acquisitions over the years, Murata has improved its portfolio with silicon capacitors and RF switches. And the SAW filter is still being improved as is evident with the recent development of TF- SAW technology. The performances can be comparable to BAW filters at a lower cost.

Behind the technology competition, the US & China trade war is another factor and is clearly impacting the RF industry. As an example, Huawei worked with Skyworks and Qorvo in the past, however trade wars makes it difficult for them to buy components from such companies based in the US.

Click here for more on BAW vs SAW Filters.

Click here to download the SAW Filter Comparison 2020 Report.