IPD platforms – A new approach to passives in RF front-end modules – An interview with Xpeedic

Despite a slow market entry, thin-film integrated passive devices (IPDs) have managed to penetrate a few passive applications and find growth drivers over the past decade. The main market today showing strong growth is custom radio frequency (RF) IPDs featured in RF modules, especially for future 5G applications. These are filters for large-frequency bands and lumped-element circuits for impedance matching, for example. This market is expected to see an 8.2% compound annual growth rate (CAGR) from 2019-2025, surpassing $360M value in 2025. The other large-value market is off-the-shelf IPDs used for electromagnetic interference (EMI) shielding in stringent applications or for basic RF operations like baluns or filtering. This market will be worth $195M in 2025, with a 3.15% CAGR from 2019–2025, as mentioned in Yole Développement’s Thin-Film Integrated Passive Devices 2020 report.

In this context, some innovative companies are developing new solutions to accompany IPD growth and the 5G opportunity. One such company is covered today by Antoine Bonnabel, Technology & Market Analyst, RF devices and technology at Yole Développement. He will be interviewing Feng Ling, Founder and CEO of Xpeedic, a leading IPD provider for RFFE modules.

Antoine Bonnabel (AB): Could you please describe your position and mission at Xpeedic to our readers?

Feng Ling (FL): I am the founder and CEO of Xpeedic. Our mission is to accelerate the integrated circuit (IC), package, and system design with our disruptive electronic design automation (EDA) solution. In the area of RF front-end (RFFE) designs, Xpeedic not only brings our EDA solution to the market but also directly supplies IPD filters to RFFE module customers.

AB: Can you please introduce Xpeedic’s EDA solution for IPD development?

FL: Xpeedic’s EDA solution for IPD development started with the development of our electromagnetic (EM) solver IRIS for on-chip passives and interconnects. With IRIS being certified by several IPD foundries, we made a dedicated IPD design platform by adding Process Design Kit (PDK) model generation and the synthesis tool iModeler, schematic level optimization, yield analysis, design-of-experiment (DoE) analysis, and package co-simulation. Along with our built-in templates for filters, couplers, and diplexers, we can quickly design IPDs from specification to volume production.

AB: Your EDA solution is aimed at foundry service providers. What interesting features do IPD solutions bring to their customers?

FL: The most interesting feature of our IPD solutions is their capability to achieve first-pass silicon success, which is critical for our customers in the mobile industry due to their tight design cycle.

AB: What are the main advantages of IPD filters for 5G bands and matching circuits?

FL: Our high-resistivity silicon (HRSi)-based IPD has the advantage of compact size, low profile, and easy packaging compared to low temperature co-fired ceramics (LTCC) and surface mount device (SMD) components for 5G band and matching circuits. Its bandwidth advantage also helps IPD as an important player in 5G New Radio (NR) and WiFi 6.

AB: How can an adequate EDA solution and a tight partnership with the foundry service provider reduce the time to development and potential cost for IPD-based lumped element circuits or filtering solutions?

FL: The key is to have a foundry-proven EM simulator that can not only generate accurate PDK models for the schematic level optimization purpose but also simulate the entire filter even with the package included. With that, we can achieve first-pass design success.

AB: Could you share your IPD-based filter design performance such as insertion loss and out of band rejection, for instance on band N77?

FL: A typical IPD N77 filter can achieve 1.5dB insertion loss and 30dB rejection within 0.5mm² die size. To be more integrated, matching filters and dual filters are also well applied in many front-end modules.

AB: Most current passive solutions are Low Temperatue Cofired Ceramic (LTCC) and standard Surface Mount Device (SMD) components. Do you think IPD is complementary to these technologies? Or will it take market share from them in the future?

FL: Complex RF front ends require more integrated passive solutions. Thin-film IPD devices bring compact, low profile, and packaging-friendly alternatives to front end modules. From both technical and bill of material (BOM) management perspectives, we think IPD will grab some market share in the future for sure.

AB: What should motivate most growth in the IPD market in the next few years?

FL: Compared to LTCC and SMD components, IPD has the advantage of being compact and package-friendly. With our close foundry partnership, custom IPD filters can be easily made. All of these factors will drive most of the growth of the IPD market in the next few years.

AB: Xpeedic is well integrated in the Chinese ecosystem. Do you see a growing trend in China toward the use of these integrated platforms?

FL: We have seen a growing trend in IPD adoption in China with strong demand from 5G. Xpeedic’s capability to supply the IPD filters with fast turn-around time to those RF front end module companies has brought us many design wins. The geopolitical tension between US and China further accelerates the adoption of Xpeedic’s IPD in the Chinese ecosystem with domestic supply chain being part of the equation.

AB: Do you see any difference between the Chinese ecosystem demands and the Western and non-Chinese East Asian current demands?

FL: The Chinese ecosystem is very dynamic and diversified. Unlike the Western and non-Chinese East Asian ecosystem, where big companies like Skyworks, Qorvo, and Murata have a complete supply chain and design capability for filters to manufacture their own RF front end modules, the Chinese ecosystem is very segmented with many relatively small but fast growing players that rely on partnerships with company such as Xpeedic for their filter needs.

Feng Ling is currently Founder and CEO of Xpeedic, a leading EDA software and RF filter provider. Dr. Ling has over 20 years of industry experience in EDA, RF front end, and system-in-package spanning from Motorola, Neolinear, Cadence, Physware, to Xpeedic. Dr. Ling received his Ph.D. degree in electrical engineering from the University of Illinois at Urbana-Champaign (UIUC) in 2000. He is a Senior Member of IEEE. He has authored and co-authored 3 book chapters and more than 60 papers in refereed journals and conference proceedings.

Antoine Bonnabel works as a Technology & Market Analyst for the Power & Wireless team of Yole Développement (Yole). He carries out technical, marketing and strategic analyses focused on RF devices, related technologies and markets. Prior to Yole, Antoine was R&D Program Manager for DelfMEMS (FR), a company specializing in RF switches and supervised Intellectual Property and Business Intelligence activities of this company. In addition, he also has co-authored several market reports and is co-inventor of three patents in RF MEMS design. Antoine holds a M.Sc. in Microelectronics from Grenoble Institute of Technologies (France) and a M.Sc. in Management from Grenoble Graduate School of Business (France).

Thin-Film Integrated Passive Devices 2020
5G and 3D integration are pushing the IPD market towards further growth.