Shift in Consumer Focus Drives Evolution of the Semiconductor Industry

John Brewer, Vice President, Corporate and Business Development, SiGe Semiconductor

A decade ago, consumer demand for electronics products fixated on high-end primary features—"my mobile phone has a color screen," "my laptop has a 1 GHz processor," "my television screen is larger than yours"—for which consumers willingly paid premium prices. Today's electronics consumer, however, has become much more sophisticated and, therefore, much more demanding. David Carr, business writer for The New York Times, framed this sophistication recently during an interview on "The Charlie Rose Show." Relating his decision to buy the newly released Apple iPad for his family, Carr commented, "I love the features, I love the performance, but what drove me to buy this for my family was the $499 price." Economics defines value as the ratio of quality to price, or putting it in the language of T-Mobile's advertising, "getting more." The proliferation of electronic device features and performance means today's consumer assumes quality and buys on price.

But consumer demands have driven more than only device features and performance. The proliferation of wireless connectivity— short-range Bluetooth, wireless local area network (WLAN) (Wi-Fi), real-time location utilizing global positioning satellites (GPS), and wide area wireless (Worldwide Interoperability for Microwave Access (WiMAX) and cellular)—across the wide range of consumer electronics applications feeds a seemingly insatiable consumer demand for unfettered interactivity and access. Mobile phones have become smartphones—productivity and entertainment devices that also happen to do voice communications. Nintendo's clever use of infrared wireless, micro-electromechanical structure (MEMS) and Bluetooth technologies in eliminating wires from the handheld controller in the Wii redefines the gaming experience while creating a disruptive new segment in the market. And it did so at a price point significantly below its competition. Today's mobile industry embraces Wi-Fi as a means of satisfying consumer demand for high-speed mobile Internet access without spending billions of dollars on network infrastructure. Consumers demand a feature-based user experience limited only by their imaginations, leaving suppliers to create ways of improving user experience inside specific price points.

In its never-ending pursuit of consumer imagination, the electronics industry repeatedly turns to the semiconductor industry for the alchemy enabling yet another new level of innovation and cost reduction. Semiconductors have and will continue to fuel the evolution of consumer electronics. The microprocessor industry stretches the physical limits of photolithography in its quest to increase computation speed and functionality while decreasing power consumption. The analog industry increases functional integration in data converters, power management and display drivers while driving performance and cost. And yet, of all the semiconductor segments, it is the radio frequency (RF) wireless physical layer where the new consumer focus on value drives the most dramatic changes.

Figure 1. Total Available Market for Cellular and Wi-Fi RF Power Amplifiers and Front-Ends

Dramatic growth in the demand for RF power amplifiers (PAs) and front-ends results from a combination of the rapid expansion of wireless connectivity in consumer electronics and the proliferation of multiple RF bands used worldwide for various wireless communications technologies.

Source:  Strategy Analytics, August 2009

More than any other product feature, RF functional integration fuels the pervasive expansion of wireless connectivity. Bluetooth was obscure until single-chip silicon-based systems-on-chip (SOCs) drove solution cost below $5. Now, soccer moms use Bluetooth for hands-free voice as well as for displaying photos on digital picture displays in their homes. In 2006, GPS was a multi-chip solution costing $10 and suitable only for personal navigation devices. Today, single-chip and two-chip silicon-based GPS system solutions sell for less than $3. As a result, location has rapidly become "the little black dress" of consumer electronics, coming to market in smartphones and digital cameras, spurring the development of photo geotagging and "find-a-friend" mobile phone services. Driven by the unique functional integration features of silicon, Wi-Fi now follows the path of Bluetooth and GPS. Silicon-based two-chip dual-band 2.4/5 GHz 802.11abgn solutions currently bring Wi-Fi connectivity to smartphones, flat-panel televisions, video-enabled computers and network routers. Single-chip CMOS-integrated PA solutions provide 802.11abg functionality in netbooks and peripherals. Key connectivity solution providers, including Atheros, CSR, Marvell and Broadcom, continue the march of integration through multifunction solutions bringing Bluetooth, Wi-Fi, GPS and FM radio together into a single device footprint.

If the explosion of wireless connectivity is driven by functional integration, the fuel for that explosion is silicon technology. Leaders such as Silicon Laboratories and Atheros drove the migration of RF transceiver technology to a fabless silicon model over the last decade in integrating the RF transceiver with the digital signal processor (DSP) on CMOS technologies. At the same time, captive gallium arsenide (GaAs) heterojunction bipolar transistor (HBT) technologies were uniquely capable of the requirements of the RF front-end—PA, RF switch and low-noise amplifier (LNA)—for consumer electronics. Suffering from the cost-based functional integration limits of GaAs technology and incompatibilities in wafer processing with silicon, GaAs-based RF front-ends put a hard limit on wireless connectivity functional integration. This separation of the RF physical layer from the RF transceiver and DSP defined a hard limit on the performance, cost and footprint of wireless connectivity signal processing.

However, advances in silicon BiCMOS and CMOS technologies are the spark for the next stage of evolution in wireless connectivity solutions. Over the last five years, silicon BiCMOS—a mixed-signal CMOS technology with the added feature of an HBT for use in the RF signal path—has moved to replace GaAs HBT technology in 802.11abgn RF PAs and RF front-ends. In particular, silicon germanium (SiGe) BiCMOS technology leads this revolution, utilizing germanium doping in the base of the silicon HBT to increase transistor speed and decrease junction noise. Combining the best features of HBTs for RF and CMOS for bias, control and digital interface, SiGe BiCMOS is today the most common manufacturing technology for RF PAs and front-ends across the consumer Wi-Fi market. Its ability to deliver on the challenges of performance, functional integration and cost is driving the penetration of Wi-Fi technology deep into mobile communications, in-home video and gaming entertainment, and computing—and in the process enabling multimedia capabilities across consumer electronics. By delivering GaAs-equivalent performance with the manufacturing advantages of silicon sourced by some of the world's largest wafer foundries, SiGe BiCMOS leads the evolution of the last layer of wireless connectivity technology—the RF front-end—in response to consumer demand for value.

Figure 2. Evolution of 802.11abg RF Front-End

Advances in SiGe BiCMOS process technology create the opportunity to reduce physical footprint and cost while improving performance. The move from multi-chip modules to single-chip implementations, unique to silicon-based technologies, fuels the expansion of wireless connectivity across the consumer electronics market.

Source: SiGe Semiconductor

Additional advances in silicon foundry process technologies serve to strengthen its value for consumer wireless RF front-ends. New developments in silicon-on-insulator (SOI) material support the integration of RF switches, PAs, LNAs, and bias, control and digital interface onto a single RF front-end IC. The addition of through-wafer vias (TWVs) to SOI enables the expansion of GaAs-equivalent RF performance on silicon into the 5 GHz band—the top end of the RF range for today's consumer electronics wireless applications. Merging best-in-class RF performance with silicon manufacturing efficiencies on 200mm wafers sets a new standard in wireless for achieving increased performance and functionality while driving cost.

For a decade, consumer electronics original equipment manufacturers (OEMs) such as Samsung have pushed the semiconductor industry towards the dream of a single-chip wireless solution—in particular a single-chip mobile phone. In response, a range of academics and start-ups have broken ground for the major communications baseband vendors in pursuit of the final piece of that dream—the CMOS RF PA. The primary challenge on the path to integrating the PA with an RF transceiver and baseband lies with the PA architecture itself. Traditional HBT-based PA architectures simply do not map to CMOS technology due to limitations rooted in the physical structure of the CMOS transistor. A decade of CMOS PA architecture trial-and-error has recently yielded integrated PA solutions appropriate for low-end 802.11abg applications such as Universal Serial Bus (USB) dongles, netbooks and printers. And CMOS PAs suitable for entry-level mobile phones continue to improve in cost effectiveness. While these advances in CMOS PA architecture do not obey Moore's Law—they don't scale well with decreasing device geometries—they do represent a meaningful addition to the silicon-based RF front-end technology that is core to meeting the wireless connectivity demands of today's consumer.

But the evolution of RF front-ends to silicon technology is about much more than technology substitution for the sake of product cost. Advances in SiGe BiCMOS and CMOS RF PAs are liberating the consumer wireless connectivity industry from the cost and capacity constraints of the mostly captive GaAs manufacturing industry. As the total available market for consumer RF front-ends expands from 2.8 billion units in 2009 to 6.0 billion units in 2012, the constraints of the worldwide GaAs wafer industry—captive and foundry— promise to restrict the feature-rich imagination of consumers and their desire for "wireless multimedia everywhere." For example, IBM Microelectronics alone has more available silicon-based RF PA and front-end die capacity than the entire GaAs industry. The existing SiGe BiCMOS foundry capacity, including IBM Microelectronics, TSMC, TowerJazz, CSM and STMicroelectronics, can, with existing fab capacity, supply the demands for RF front-ends in consumer electronics into the foreseeable future. It is readily apparent that the potential for wireless connectivity in consumer electronics can only be fully realized upon the evolution of RF front-end manufacturing to silicon technology.

And that evolution signals fundamental changes in the RF semiconductor industry. The history of semiconductors validates two fundamental points. First, the evolution of products to the silicon platform signals dramatic expansion in the serviceable market for those products. Second, the evolution of product manufacturing from captive fabs to the foundry model drives the convergence of manufacturing technologies. The explosion in all forms of voice and data communications over the last 20 years is in no small part due to the freeing of capital from investment in captive semiconductor fabrication facilities and technologies.

The fabless product development model complements this convergence in semiconductor technologies through broadening product-level innovation. Through a focus on circuit and system design instead of manufacturing technology for product differentiation, reaction to consumer demand for value becomes increasingly responsive. And this convergence in turn increases the efficiency of the semiconductor industry through consolidation for both manufacturers and fabless design houses. Particularly in the case of RF semiconductors, the fabless model encourages a move away from the reliance upon sole-sourced single-point-of-manufacturing supply of critical components that has driven consumer electronics OEMs crazy for two decades. The success of companies such as Atheros and Broadcom testifies to the importance of the fabless semiconductor model in the face of the always increasing demands of communications technologies.

The transformation of the RF physical layer away from exotic technologies to silicon-based manufacturing signals the final inflection point in the expansion of wireless multimedia communications for consumer electronics. Silicon-based RF front-ends represent "the third wave" of silicon, following the path of microprocessors and analog signal processing towards system-level functional integration, widely available wafer capacity and industry-standard product design techniques. As such, RF front-end functionality continues the evolution from its reputation as temperamental "black magic" to a readily available, value-oriented, highly manufacturable portion of wireless connectivity solutions. In addition, silicon-based RF PAs and front-ends enable consolidation in the consumer electronics sector of the semiconductor industry, resulting in a leaner, stronger semiconductor foundry sector and increasing opportunity for innovation in RF front-end product technologies from fabless companies. In these ways, the consumer's shift from a focus on high-end features to value-driven pricing in electronic products has driven a necessary evolution in RF front-end manufacturing to silicon-based technologies. The result: increased satisfaction of the consumer's seemingly unbounded imagination for "wireless multimedia everywhere."

About the Author

John's 25 plus years in the wireless semiconductor industry extend across the disciplines of engineering, marketing and executive management. John joined SiGe Semiconductor in 2006 and currently serves as vice president of corporate and business development. He has spent the last 13 years working on products and technologies related to improving the performance and manufacture of RF PAs for mobile wireless communications. Prior to joining SiGe Semiconductor, he was the chief executive officer and president of Xindium, a company providing RF PAs for next-generation mobile handsets and terminals. Previously, he founded Vincio, a marketing consultancy serving wireless communications component developments with clients ranging from Xerox Palo Alto Research Center to GaN RF power transistor pioneer Nitronex. John was also a founder and vice president of marketing for Tropian, a company that developed a revolutionary approach to improving the efficiency of mobile phone RF PAs. John holds a B.S. degree in electrical engineering from Santa Clara University. You can reach John Brewer at jsb@sige.com or 503-453-2765.

Back to Articles Home