Specialty foundry TowerJazz is ramping a 65nm version of its RF-SOI process on 300mm wafers at Fab 7 in Uozu, Japan. To support the ramp, the company has signed a contract with long-term partner, Soitec, guaranteeing a supply of tens of thousands of 300mm SOI silicon wafers, securing wafer prices for the next years and ensuring supply to its customers, despite a tight SOI wafer market.
Five of TJ’s seven fabs do RF-SOI. LNA (low-noise amplifers) are a big market driver, and with RF-SOI they can integrate the LNA with the switch, CEO Russell Ellwanter said in his lead keynote at the SOI Consortium’s 5th International RF-SOI Workshop in Shanghai (spring, 2018). BTW, that was in fact a very inspirational talk about Value Creation, and the importance of treating your suppliers with respect. He credited his company’s close relationship with RF-SOI wafer-supplier Soitec for TJ’s claim to the world’s best linearity.
“We are delighted to see the strong adoption of 300mm RF SOI through this large capacity and supply agreement with TowerJazz to augment our already significant 200mm RF-SOI partnership,” said Soitec CEO Paul Boudre. “TowerJazz was the first foundry to ramp our RFeSI products to high volume production in 200mm and continues as one of the industry leaders in innovation in this exciting RF market with advanced and differentiated offerings.”
According to the TJ press release (you can read it here), with its best in class metrics the TowerJazz 65nm RF-SOI process enables the combination of low insertion loss and high power handling RF switches with options for high-performance low-noise amplifiers as well as digital integration. The process can reduce losses in an RF switch improving battery life and boosting data rates in handsets and IoT terminals.
It’s a high-growth market, to be sure. Market researchers Mobile Experts predict that the mobile RF front-end market will reach $22 billion in 2022 from an estimated $16 billion in 2018. TowerJazz says its breakthrough RF SOI technology continues to support this high-growth market and is well-poised to take advantage of next-generation 5G standards, which will boost data rates and provide further content growth opportunities in the coming years.
Customers are already getting into position. For example, Maxscend (WuXi, China), a provider of RF components and IoT integrated circuits, is ramping in this new technology. “We chose TowerJazz for its advanced technology capabilities and its ability to deliver in high volume while continuously innovating with a strong roadmap. We specifically selected its 300mm 65nm RF SOI platform for our next-generation product line due to its superior performance, enabling low insertion loss and high power handling,” said Maxscend CEO Zhihan Xu.
As longtime ASN readers will know, we’ve been covering the evolutions of TJ’s RF-SOI platforms since the beginning of the decade. It’s worth noting, too, that beyond RF, TowerJazz also offers foundry customers other SOI-based processes, such as the new 0.18μm BCD SOI, a 200V SOI technology platform (announced in 2017, press release here) for motor drivers, industrial tools, electric vehicles and more. The previous generation 0.18μm SOI for automotive power management also offers exceptional area savings and is well-suited for high temperature operation. Back in 2014, here at ASN we did a great interview with TJ SVP Dr. Marco Racanelli about when and why they use SOI – and while processes have advanced, the basic drivers are still there, so it’s a still a good read.
And finally, designers will want to know that the TJ Multi-Project Wafer (MPW) Shuttle Program offers the 65nm RF-SOI process, as well as other SOI-based processes. See the website for scheduling and details.
“GlobalFoundries, TowerJazz, TSMC and UMC are expanding or bringing up RF SOI processes in 300mm fabs in an apparent race to garner the first wave of RF business for 5G, the next-generation wireless standard,” writes Mark Lapedus of Semiconductor Engineering. His recent piece, RF-SOI Wars Begin, explains why demand across the supply chain is currently tight.
Rest assured, the supply situation is being addressed fast. By next year, 300mm-based RF-SOI manufacturing (vs. 200mm) will increase from 5% to 20%. But with insatiable end-user demand for greater throughput, overall RF-SOI device demand is increasing in the double-digit range, so 200mm-based manufacturing is also expanding fast.
SOI wafer manufacturer Soitec has 70% of the RF-SOI wafer market share. The other RF-SOI wafer manufacturers – Shin-Etsu, GlobalWafers and Simgui – all use Soitec’s RF-SOI wafer manufacturing technology.
This is an excellent, comprehensive piece, that clearly explains the complexities of the markets, the devices, the manufacturing and the supply chain. It’s a highly recommended read.
BTW, the SOI Consortium is organizing a 4G/5G SOI supply chain workshop during Semicon West (July ’18). Sign up or get more information on that under the Events tab here on the consortium website.
Of course, here at ASN, we’ve been covering RF-SOI for over a decade. You can use our RF-SOI tag to access most of the pieces we’ve done over the years.
As you may have read in the first part of this series, Soitec (the industry’s leading supplier of SOI wafers) says its 200mm RF-SOI wafers have been used to produce over 20 billion chips, and the company is now in high-volume manufacturing of a 300mm version of its wildly successful RFeSI line (see press release here).
So far it’s been all about RF front-end module – aka FEM – chips that handle the back-and-forth of signals between the transceiver and the antenna, originally in 2G and 3G phones. For 4G/LTE-A (and 5G when that hits), there were new wafer innovations – and now 300mm wafers.
The newest RF-SOI wafers, Soitec’s RFeSI90 series (available in both 200mm and 300mm diameters), offer higher levels of performance such as better uniformity, which chip designers need to achieve greater control of transistor matching in analog designs. Plus with the new wafers designers can use thinner transistors and additional process options to improve RonCoff performance, the figure of merit that’s used to rate the performance of an RF switch. For Soitec customers (and really, anyone doing FEMs these days is a customer), all these advances plus the large supply of 200mm and 300mm wafers means that they can expand their production capacities for RF-SOI devices and produce more highly integrated ICs.
GlobalFoundries, for example, sang the praises of 300mm wafers for RF-SOI at a recent SOI Consortium forum in Tokyo. Here’s a slide from Peter Rabbeni’s talk, (he’s GloFo’s Sr. Director RF Product Marketing and Biz Dev), RFSOI: Defining the RF-Digital Boundary for 5G (you can get the full presentation here):
As you see in the slide above, RF-SOI champion Peregrine Semiconductor introduced the industry’s first 300mm RF-SOI technology – that was back in July 2015. Dubbed UltraCMOS® 11, it’s built on GlobalFoundries’ 130 nm 300mm RF technology platform (read about it here).
Looking forward, GF’s Rabbeni noted, “Significant R&D has been done in evaluating the application of SOI to 5G architectures, with very positive results. SOI holds great promise in delivering on the key requirements of 5G systems.”
Also at the Tokyo event, Kenji Tateiwa, General Manager of R&D Strategic Planning for TPSCo (that’s TowerJazz/Panasonic), gave a great presentation on 300mm RFSOI Development toward IoT Era. 300mm RF-SOI, he noted, “has room to run.”
For Soitec, of course, work on future generations of RF-SOI substrates continues unabated. You can be sure they’ve got a product roadmap focused on continued innovation and cost effectiveness for future mobile communication markets.
But in addition to working on its RF-SOI roadmap internally, Soitec is leading an international program to further develop the technology in collaboration with 16 partners from five European countries, representing the entire electronics value chain from raw materials to finished communication products. The REFERENCE Project, awarded in a call for projects by the Electronic Components and Systems for European Leadership (ECSEL) group ─ aims to create a European competitive industrial ecosystem based on RF-SOI.
Over the next three years, the REFERENCE Project expects to innovate new materials, engineered substrates, processes, design, metrology and system integration that pave the way for 5G wireless communications. The R&D and demonstration objectives for 4G+/5G technologies include Soitec’s development of RF-SOI substrates, and the production of RF-SOI devices at two major European semiconductor foundries. These advances will contribute to RF-SOI’s growing use in three targeted applications: cellular communications/the Internet of Things (IoT), automotive and aeronautics , including pioneering new frequency bands.
“Soitec is at the forefront of European innovation and we are very happy to be part of this very important European research project involving key partners beyond our direct customers,” said Nelly Kernevez, partnership director at Soitec. “This initiative allows us to build the European Union’s RF community, consolidate our vision of what the future can be, and leverage proven material technology to create RF communication solutions for tomorrow.”
The wireless world will keep progressing by leaps and bounds over the next few years. And it’s looking like ever-advancing RF-SOI substrates will be the springboard. Stay tuned!
EDI CON China 2016, taking place April 19-21 in Beijing at the China National Convention Center (CNCC) will feature a keynote talk by GlobalFoundries‘ Peter Rabbeni, Sr. Director, RF BU Business Development & Product Marketing. The talk, entitled, “RF SOI: Revolutionizing Radio Design Today and Driving Innovation for Tomorrow”, will kick off the newly added RF-SOI Technology Track. The SOI Track will also feature talks and workshops from Peregrine Semiconductor, TowerJazz, Simgui, AnalogSmith and Shanghai Jiao Tong University. The talks will cover substrate engineering, design enablement, CMOS power amplifier design techniques and highly integrated control devices.
Mr. Rabbeni’s keynote talk will cover how there has been dramatic growth in RF SOI over the last several years in its continued march in driving performance improvement, cost reduction and architecture innovation between the transceiver and the antenna in mobile radios. No other radio technology in recent memory has had the impact that RF SOI has had in this respect. With standards becoming increasingly more challenging and the pending introduction of 5G, RF SOI is expected to continue to play an important role in the development of innovative architectures. His presentation will explore where we have been, why and where we may be headed with this technology. Substrate engineering and SOI device technology is reviewed in detail in Microwave Journal’s October 2015 cover story at http://www.microwavejournal.com/articles/25255.
More information is available at www.ediconchina.com.
With the acquisition of Maxim’s 8-inch fab in San Antonio, Texas, TowerJazz plans to quickly qualify its core specialty technologies, including its advanced Radio-Frequency Silicon-on-Insulator (RF-SOI) offering, to serve the substantial growth in demand from its customers. (See press release here.)
The proposed purchase will expand TowerJazz’s current worldwide manufacturing capacity, cost-effectively increasing production by approximately 28,000 wafers per month. The availability of additional capacity is expected to be needed to serve TowerJazz’s current and forecasted robust customer demand. TowerJazz and Maxim expect to close the transaction in January 2016, subject to customary closing conditions.
Is RF-SOI the same thing as RF on FD-SOI? No, it’s not. However, the runaway success of RF-SOI and the growing list of recent announcements related to FD-SOI with integrated RF has lead to some confusion in the press and social media. The two are different technologies, addressing different markets, and built on two very different types of SOI wafers. The use of one technology or the other depends on the requirements of the targeted RF application.
For the non-technical reader, here is a bit of basic background. At the most simplistic level – RF: radio frequency – is part of the analog family, and as such is all about waves. And when you talk about waves, you talk about losses over distance (attenuation), speed, wavelength and frequency – which is why the RF design has a rep of being something of a black art. The distance to cover, the power envelope and the amount of data to carry over that distance (and of course, the cost) determine the chip solutions. An important part of the RF chip solution is the choice of the wafer substrate itself.
So here’s a quick primer to help sort out what’s what. Please bear in mind, though, that this is a fast-evolving world, so what you’re about to read is not a definitive and forever what’s what – but more of a general (and simplified) “this is how it is currently shaking out”.
RF-SOI – Talk to the Tower
When it comes to using your mobile device for data transmission over a 2G, 3G, 4G/LTE/LTE-A (and next, 5G) network, you still need dedicated RF front-end modules (FEMs). FEMs handle the back-and-forth of signals between the transceiver and the antenna. They contain multiple parts, including switches, power amplifiers, antenna tuning, power management and filters. Traditionally, they were built on gallium arsenide substrates. But more and more, the multiple chips in FEM chipsets are being reduced to single SOCs built on a special class of high-resistivity SOI wafers. This is the realm of RF-SOI. The wafers for RF-SOI are designed specifically to handle the special needs of getting a lot of data transmitted wirelessly, often over relatively long distances.
The latest standards (LTE-A and 5G) raise the stakes ever higher, requiring mobile devices to support more bands, higher frequency bands, and emission and reception on adjacent bands with downlink and uplink carrier aggregation. (Carrier aggregation refers to the simultaneous reception of multiple frequency bands to improve data throughput.)
For RF designers, that means choosing substrates that favor low RF loss and high RF linearity. A couple of years ago, SOI leader Soitec, in partnership with UCL, brought breakthrough RF-SOI wafer technology to the market (read about that here). Now, a few generations later, Soitec estimates that one billion RF devices are produced each quarter using their advanced and enhanced Signal Integrity™(eSI)wafers for RF. In fact it would be nigh near impossible to find a smartphone that doesn’t have an RF FEM based on RF-SOI wafer technology.
Here at ASN, we’ve covered many of the leaders in RF-SOI FEMs over the last few years. Click on any of these names to get an idea of what they’re doing: IBM (now part of GlobalFoundries), Peregrine, SkyWorks, TowerJazz, ST, Qorvo, Sony, Qualcomm, Grace, Toshiba and MagnaChip. To learn more about the latest developments in wafer technology for RF-SOI, click here. With demand soaring, Soitec’s most advanced RF-SOI wafers are now also being produced by Simgui in China – read about that here.
In fact, the cover story and technical features of the October 2015 issue of the prestigious Microwave Journal is dedicated to RF-SOI – click here to read it.
So in terms of terminology, that’s “RF-SOI”. Now let’s look at how RF on FD-SOI is different.
RF in FD-SOI – for digital integration
When we talk about RF in FD-SOI, we’re typically talking about some RF functionality being integrated into SOCs that are essentially digital processors. True, you can integrate RF functionality into an SOC built on planar bulk (it’s generally agreed to be a nightmare in bulk FinFETs, though). But you can integrate RF into your digital SOC much more easily, efficiently and with less power if you do it in FD-SOI.
RF/analog has a (well-deserved) rep of being the most challenging part of chip design. Analog/RF devices are super sensitive to voltage variations. The digital parts of a chip, which have strong, sudden signal switching, can raise havoc with nearby analog/RF blocks. This means that the analog/RF designers have to care acutely about gain, matching, variability, noise, power dissipation, and resistance. They use all kinds of specialized techniques: FD-SOI makes their job a lot easier (good explanation in slide 8 here). What’s more, FD-SOI’s analog performance far exceeds bulk.
What sort of chips are we talking about? For now, we’re talking about processors for mobile devices, for IoT, for automotive, for consumer electronics. When we say “RF in an FD-SOI SOC”, we’re currently talking about chips that are connecting over a relatively short distance to a nearby box or device (<100m for local WiFi, or a few meters for Bluetooth or Zigbee, for example).
ST’s new set-top-box processors on 28nm FD-SOI (read about them here) are a great example. They are the first on the market integrating 4×4 802.11ac Wi-Fi (using IP from Quantenna) and High Dynamic Range support. This means the set-top boxes can reliably serve lots of HD video via WiFi to multiple users throughout the house (hopefully ending the cry: “Who’s hogging all the Wifi?!?”). ST credits their 28nm FD-SOI silicon technology with providing that highly-efficient RF, state-of-the-art WiFi performance and robustness required for reliable video delivery inside the home.
For RF on FD-SOI – as in other FD-SOI apps – designers use SOI wafers with ultra-thin silicon, ultra-thin insulating BOX and phenomenal top silicon thickness uniformity. These wafers are not the special high-resistivity wafers used in RF-SOI. Rather, they are the latest generations of the same (amazing!) FD-SOI wafers that Soitec introduced in 2010. (For an excellent, in-depth interview with the Soitec FD-SOI wafer guru on the supply chain and the most recent developments, click here.)
This is the type of wafers that GloFo, ST, Samsung, Freescale, Sony, several other companies in Japan and many more around the world are using when they say they’re doing RF on FD-SOI. Bear in mind that this level of SOC integration is fairly new (Samsung and TSMC just announced RF integration into SOCs for the first time in 2014 on 28bulk). But using FD-SOI technology and the corresponding ultra-thin SOI wafer substrates makes life much easier for the RF folks on the design teams, gets far better performance and far lower power at a much more attractive cost.
Further ahead, FD-SOI is also a candidate for transceivers and baseband/modem SOCs, which require high-performance digital and analog/RF integration. But even with transceivers on FD-SOI, you’ll still need the FEM on RF-SOI to handle the interface.
So, that’s the current difference between RF-SOI and RF on FD-SOI.
Hope that helps to clear things up?
A very successful two-day forum on FD-SOI and RF-SOI in Shanghai (September 2015) featured presentations from CEOs, CTOs and VPs at GF, ST, Leti, ARM, Verisilicon, Synapse Design, SITRI, Skyworks, Freescale, TowerJazz, Soitec, Qorvo and many more. Most of the presentations are now available on the SOI Consortium Website, and the rest are expected shortly, so keep checking back.
To download the “Design for FD-SOI” presentations, see the list here.
To download the “RF-SOI Workshop – Interconnected World” presentations, see the list here. (Presentations from all of the major SOI wafer suppliers are also available on this page.)
Global specialty foundry TowerJazz and TowerJazz Panasonic Semiconductor Co. (TPSCo), the leading analog foundry in Japan, have announced breakthrough RF-SOI technology for next-generation 4G LTE smartphones and IoT devices. Through a collaborative effort, TowerJazz and its majority owned subsidiary, TPSCo, have developed a new 300mm RF-SOI process that can reduce losses in an RF switch by as much as 30% relative to current technology, improving battery life and boosting data rates. The technology achieves a record Ron-Coff figure of merit of sub-90fs and is now being sampled to a lead customer. (Read the press release here.)
Specialty foundry TowerJazz announced the availability of an enhanced RF-SOI CMOS process design kit (PDK) for its 0.18µm process technology (see press release here). The kit was developed for use with Agilent Technologies’ Advanced Design System (ADS) software and targets a wide range of analog markets including front-end modules for mobile phones, tablets and WiFi terminals.