Category Archives: MEMS

Despite strong double-digit percentage increases in annual unit shipments, semiconductor sensor sales growth has become uncharacteristically lethargic because of steep price erosion in several major product categories. Strong unit demand is being fueled by new wearable systems, greater automation in vehicles, and the much-anticipated Internet of Things (IoT), but sharply falling average selling prices (ASPs) on accelerometers, gyroscope chips, and magnetic-field measuring devices are capping annual growth of total sensor revenues in the low- to mid-single digit range, based on data in IC Insights’ 2016 O-S-D Report—A Market Analysis and Forecast for Optoelectronics, Sensors/Actuators, and Discretes.

The 2016 O-S-D Report shows worldwide dollar-volume revenues for sensors rising by a compound annual growth rate (CAGR) of 5.3% between 2015 and 2020 compared to an 8.9% annual rate in the last five years. In contrast, total sensor unit shipments are expected to climb by a CAGR of 12.4% in the five-year forecast period compared to a blistering 20.5% rate of increase in the 2010-2015 period, when new sensing, navigation, and automated embedded control functions in smartphones drove up strong growth along with steady increases in automotive and industrial applications.

Despite recent years of weak sales growth—just 1% in 2015 to $6.4 billion—the sensor market is expected to end this decade with 10 consecutive years of record-high revenues and reach $8.3 billion in 2020 (Figure 1). Unit shipments of sensors have reached record high levels each year since the beginning of the last decade—even in the 2009 downturn year, when worldwide unit volume grew 9% while sensor revenues dropped 3%. Record sensor shipments are expected to continue for another five years, reaching 28.9 billion units in 2020, according to the 360-page 2016 O-S-D Report, which contains a detailed five-year forecast of sales, unit volume, and ASPs for more than 30 individual product types and device categories in optoelectronics, sensors/actuators, and discretes.

Figure 1

Figure 1

Competition between suppliers and requirements for low-cost sensors in new high-volume applications drove down ASPs from about $0.66 in 2010 to $0.40 in 2015.  The need to squeeze more sensing solutions into wearable systems, far-flung IoT-connected applications, and multi-sensor packages for increased accuracy and multi-dimensional measurements is exerting more pricing pressure in the market, concludes the 2016 O-S-D Report.   The report’s forecast shows sensor ASPs dropping by a CAGR of  6.3% in the next five years to only $0.29.

Total sensor sales are expected to grow by about 3% in 2016 to $6.6 billion with worldwide shipments rising 13% to nearly 18.2 billion units this year.  Sales of sensors made with microelectromechanical systems (MEMS) technology (i.e., accelerometers, gyroscope devices, and pressure sensors, including microphone chips)—are expected to grow by 4% in 2016 to $4.8 billion with unit shipments increasing 10% to 7.6 billion.  The 2016 O-S-D Report projects MEMS-based sensor sales rising by a CAGR of 5.5% in the next five years to $6.1 billion in 2020 with unit shipments growing by an annual rate of 11.9% to nearly 13.4 billion.  ASPs for MEMS-based sensors are expected to decline by a CAGR of -5.7% to $0.45 in 2020 from $0.61 in 2015, according to the annual O-S-D Report.

Although shipments of microelectromechanical systems (MEMS) sensors used in automotive applications grew 8.4 percent in 2015, revenues were flat compared to the previous year, reaching $2.7 billion. In contrast, the value of this market is expected to recover this year, rising 4.3 percent to reach $2.8 billion in 2016, according to IHS Markit (Nasdaq: INFO).

The automotive MEMS market is forecast to grow at a compound annual growth rate of 6.9 percent from 2015 to 2022, to reach $3.2 billion in 2022. Global shipments will exceed two billion units for the first time at the end of this period, according to the IHS Markit Automotive Sensor Intelligence Service.

“Just three types of MEMS devices used in the automotive industry account for more than 95 percent of market value: pressure sensors, accelerometers and gyroscopes,” said Richard Dixon, principal analyst, automotive sensors, IHS Markit. “The primary systems relying on these devices are electronic stability control systems, airbags, tire-pressure monitors and manifold absolute-pressure sensors, although IHS tracks 34 other automotive MEMS applications.”

While these markets will remain, by their nature, still relatively small by 2022, the fastest growing volume applications in the coming years will include the detection of pedestrians, air-intake humidity measurement, microphones for hands-free calling in infotainment systems and microbolometers for night-vision systems used in driver assistance. New sensor areas on the horizon include scanning mirrors for head-up displays and adaptive LED headlights.

Top 10 automotive MEMS sensor suppliers

For second-tier suppliers of automotive sensors, 2015 was a good year. However, significant devaluations of the Euro and Yen affected the businesses of several companies. Leading Germany-based sensor supplier Robert Bosch was among the companies hit by exchange rate weakness, but its business continues to soar in local currency and shipments.

Sensata followed Bosch in the second-ranked position, exhibiting subdued 2015 revenue growth, despite last year’s acquisition of CST, including the sensor business of Kavlico. Along with its strong position in powertrain pressure sensors, Sensata benefits from its high-profile acquisition of Schrader, which made it the leading supplier of tire pressure monitors.

A name new to the MEMS sensor business is NXP, whose acquisition of Freescale last year catapulted the company into third-ranked position. NXP is known for its automotive magnetic sensors, while pressure sensors and accelerometers are the key sensors brought to the company via the Freescale acquisition.

The remaining seven companies also showed subdued results, with Japanese companies like Denso (ranked fourth) and Panasonic (ranked sixth). Both companies were adversely affected by the continued softness of the Yen.

Top_MEMS_Suppliers_IHS

It looks like a small piece of transparent film with tiny engravings on it, and is flexible enough to be bent into a tube. Yet, this piece of “smart” plastic demonstrates excellent performance in terms of data storage and processing capabilities. This novel invention, developed by researchers from the National University of Singapore (NUS), hails a breakthrough in the flexible electronics revolution, and brings researchers a step closer towards making flexible, wearable electronics a reality in the near future.

Associate Professor Yang Hyunsoo from the National University of Singapore, who led a research team to successfully embed a powerful magnetic memory chip on a plastic material, demonstrating the flexibility of the memory chip. Credit: National University of Singapore

Associate Professor Yang Hyunsoo from the National University of Singapore, who led a research team to successfully embed a powerful magnetic memory chip on a plastic material, demonstrating the flexibility of the memory chip. Credit: National University of Singapore

The technological advancement is achieved in collaboration with researchers from Yonsei University, Ghent University and Singapore’s Institute of Materials Research and Engineering. The research team has successfully embedded a powerful magnetic memory chip on a flexible plastic material, and this malleable memory chip will be a critical component for the design and development of flexible and lightweight devices. Such devices have great potential in applications such as automotive, healthcare electronics, industrial motor control and robotics, industrial power and energy management, as well as military and avionics systems.

The research team, led by Associate Professor Yang Hyunsoo of the Department of Electrical and Computer Engineering at the NUS Faculty of Engineering, published their findings in the journal Advanced Materials on 6 July 2016.

Flexible, high-performance memory devices a key enabler for flexible electronics 

Flexible electronics has become the subject of active research in recent times. In particular, flexible magnetic memory devices have attracted a lot of attention as they are the fundamental component required for data storage and processing in wearable electronics and biomedical devices, which require various functions such as wireless communication, information storage and code processing.

Although a substantial amount of research has been conducted on different types of memory chips and materials, there are still significant challenges in fabricating high performance memory chips on soft substrates that are flexible, without sacrificing performance.

To address the current technological challenges, the research team, led by Assoc Prof Yang, developed a novel technique to implant a high-performance magnetic memory chip on a flexible plastic surface.

The novel device operates on magnetoresistive random access memory (MRAM), which uses a magnesium oxide (MgO)-based magnetic tunnel junction (MTJ) to store data. MRAM outperforms conventional random access memory (RAM) computer chips in many aspects, including the ability to retain data after a power supply is cut off, high processing speed, and low power consumption.

Novel technique to implant MRAM chip on a flexible plastic surface

The research team first grew the MgO-based MTJ on a silicon surface, and then etched away the underlying silicon. Using a transfer printing approach, the team implanted the magnetic memory chip on a ?exible plastic surface made of polyethylene terephthalate while controlling the amount of strain caused by placing the memory chip on the plastic surface.

Assoc Prof Yang said, “Our experiments showed that our device’s tunneling magnetoresistance could reach up to 300 per cent – it’s like a car having extraordinary levels of horsepower. We have also managed to achieve improved abruptness of switching. With all these enhanced features, the flexible magnetic chip is able to transfer data faster.”

Commenting on the significance of the breakthrough, Assoc Prof Yang said, “Flexible electronics will become the norm in the near future, and all new electronic components should be compatible with flexible electronics. We are the first team to fabricate magnetic memory on a flexible surface, and this significant milestone gives us the impetus to further enhance the performance of flexible memory devices and contribute towards the flexible electronics revolution.”

Assoc Prof Yang and his team were recently granted United States and South Korea patents for their technology. They are conducting experiments to improve the magnetoresistance of the device by fine-tuning the level of strain in its magnetic structure, and they are also planning to apply their technique in various other electronic components. The team is also interested to work with industry partners to explore further applications of this novel technology.

STMicroelectronics has introduced a new line up of world’s smallest single-chip motor drivers for the portable and wearable applications. With the combination of low power consumption and small form factor, the ST’s new motor driver plans to contribute to the battery powered IoT device adoption.

The 3mm by 3mm motor drivers will focus on combining logic and power components in a single chip while taking care of power budgets and tight space. The drivers will operate from a supply voltage of 1.8V with the standby current of less than 80nA for a zero-power state. The drivers can also be used in a wide range of applications including robotic positioning systems, printer motors, camera-autofocus mechanisms, toothbrush motors or syringe pumps.

The existence of portable devices in everyday life is becoming more significant with the considerable increase in the use of well-developed battery-powered equipment with extended run-time that becomes smaller day by day.

“Our latest STSPIN single-chip devices are proven to simplify precision motor control and cut time to market for new products,” said Domenico Arrigo, General Manager Industrial and Power Conversion Division, STMicroelectronics. “The ultra-low power consumption extends runtime in battery-operated applications and enables designers to enhance portable and mobile devices with high-added-value motorized functions.”

ST’s new STSPIN motor devices are in production and are priced from $0.75 and $0.96 for order of 1,000 pieces.

Unisem reported it recently shipped its one billionth packaged MEMS device and continues to invest capex in both MEMS assembly equipment and the development of additional factory floor space for this expanding market.

With MEMS device revenues forecasted to grow from 11.9 Billion USD in 2015 to 20 Billion USD by 2021 (Yole), Unisem sees MEMS as a strategic part of their technology and growth plans moving forward. With over 9 years of experience developing MEMS packaging solutions, Unisem estimates that their MEMS unit volumes will grow by over 50 percent over the next 12 months.
Part of Unisem’s growth strategy for MEMS packaging includes the dedication of additional factory floor space. In its factory in Chengdu, China, the company has recently completed the installation and certification of a 1200 sq. meter class 100 clean room to support the assembly needs of MEMS microphones, combination cavity packages, and other devices that either require or benefit from this level of controlled environment.

In addition to the new class 100 clean room, Unisem also has brought in Film Assisted Molding capability to support the expansion of their MEMS molded cavity package offerings. Film Assisted Molding allows Unisem to target both the automotive and industrial MEMS pressure sensor market as well as the growing market for consumer pressure, humidity, temperature, gas sensors and combinations of these. This technology enables Unisem to use leadframe based packages and to mold the sensor device itself leaving only the sensing area exposed in the cavity.

Unisem continues to make MEMS packaging a key component to its growth moving forward with continued investments in technology, equipment and factory floor space to meet their demands as they move into their next billion units of MEMS devices assembled.

Unisem is a global provider of semiconductor assembly and test (OSAT) services for electronics companies.

With an eye to the next generation of tech gadgetry, a team of physicists at The University of Texas at Austin has had the first-ever glimpse into what happens inside an atomically thin semiconductor device. In doing so, they discovered that an essential function for computing may be possible within a space so small that it’s effectively one-dimensional.

In a paper published July 18 in the Proceedings of the National Academy of Sciences, the researchers describe seeing the detailed inner workings of a new type of transistor that is two-dimensional.

Transistors act as the building blocks for computer chips, sending the electrons on and off switches required for computer processing. Future tech innovations will require finding a way to fit more transistors on computer chips, so experts have begun exploring new semiconducting materials including one called molybdenum disulfide (MoS2). Unlike today’s silicon-based devices, transistors made from the new material allow for on-off signaling on a single flat plane.

Keji Lai, an assistant professor of physics, and a team found that with this new material, the conductive signaling happens much differently than with silicon, in a way that could promote future energy savings in devices. Think of silicon transistors as light bulbs: The whole device is either turned on or off at once. With 2-D transistors, by contrast, Lai and the team found that electric currents move in a more phased way, beginning first at the edges before appearing in the interior. Lai says this suggests the same current could be sent with less power and in an even tinier space, using a one-dimensional edge instead of the two-dimensional plane.

“In physics, edge states often carry a lot of interesting phenomenon, and here, they are the first to turn on. In the future, if we can engineer this material very carefully, then these edges can carry the full current,” Lai says. “We don’t really need the entire thing, because the interior is useless. Just having the edges running to get a current working would substantially reduce the power loss.”

Researchers have been working to get a view into what happens inside a 2-D transistor for years to better understand both the potential and the limitations of the new materials. Getting 2-D transistors ready for commercial devices, such as paper-thin computers and cellphones, is expected to take several more years. Lai says scientists need more information about what interferes with performance in devices made from the new materials.

“These transistors are perfectly two-dimensional,” Lai says. “That means they don’t have some of the defects that occur in a silicon device. On the other hand, that doesn’t mean the new material is perfect.”

Lai and his team used a microscope that he invented and that points microwaves at the 2-D device. Using a tip only 100 nanometers wide, the microwave microscope allowed the scientists to see conductivity changes inside the transistor. Besides seeing the currents’ motion, the scientists found thread-like defects in the middle of the transistors. Lai says this suggests the new material will need to be made cleaner to function optimally.

“If we could make the material clean enough, the edges will be carrying even more current, and the interior won’t have as many defects,” Lai says.

The paper’s other authors are postdoctoral researchers Di Wu and Xiao Li; research scientist Lan Luan, and graduate students Xiaoyu Wu and Zhaodong Chu, and professor Qian Niu in UT Austin’s Department of Physics; and graduate student Wei Li, former graduate student Maruthi N. Yogeesh, postdoctoral researcher Rudresh Ghosh, and associate professor Deji Akinwande of UT Austin’s Department of Electrical and Computer Engineering.

Earlier this year, both Lai and Akinwande won Presidential Early Career Awards for Scientists and Engineers, the U.S. government’s highest honor for early-stage scientists and engineers.

Silicon Valley specialty semiconductor foundry Noel Technologies, a provider of process development and substrate fabrication for a variety of high-technology industries, celebrates its 20th anniversary this month. According to market data from the industry trade association SEMI, Noel Technologies is one of only two companies still offering foundry services in Silicon Valley, where there were once dozens of wafer-fabrication facilities.

Using industry-standard process flows and materials, Noel Technologies develops and perfects semiconductor-manufacturing recipes for customers in the IC, renewable energy, automotive electronics, LED lighting, optoelectronics, MEMS and other nanoelectronics industries. The foundry can work with traditional silicon wafers up to 450mm as well as non-standard substrates including III-V compound materials, glass and fused silica.

The company provides chip makers with a bridge from IC development work to volume production, a much-needed service in proving the viability of new devices and innovative manufacturing processes. The multi-billion-dollar cost of building today’s wafer fabs has led many semiconductor companies to adopt a “fabless” strategy by outsourcing chip manufacturing to a foundry, many of which are located in Asia.

“While other companies have moved their fabrication operations out of Silicon Valley – whether in pursuit of lower labor costs, tax holidays or other financial incentives – we are dedicated to working with local and far-off semiconductor companies on their prototyping, pilot manufacturing and production needs,” said Leon Pearce, founder and chief technical officer of Noel Technologies.

To deliver short cycle times and maximize the utility of its installed equipment base, Noel Technologies operates seven days a week, 20 hours per day. Projects vary in size from single wafers to thousands per month, depending upon each customer’s unique needs.

Pearce and his daughter Kristin Boyce, president of Noel Technologies, co-founded the company in 1996 with three employees. Through strategic technology additions, tool acquisitions and facility expansions, they have grown the staff to 50 personnel. Hill joined the company 12 years ago, leveraging her extensive semiconductor experience to expand Noel Technologies’ foundry services and better serve its broad customer base. Together, the three senior executives focus on customer needs, emerging market requirements and new applications.

The company continues to operate at its original location and has no corporate debt, both extreme rarities in the semiconductor industry. Noel Technologies owns and operates a Class 100 cleanroom facility equipped with tools that support its process-driven services model and run by a well-trained engineering department.

9:00 am – 10:00 am
“CONNECT” Executive Summit
SEMI’s Denny McGuirk moderates a panel of execs from Lam, Qualcomm, Intel and Entegris
Keynote Stage

9:00 am – 3:00 pm
Women in Technology Forum
Room 304, Esplanade

12:30 am –2:00 pm
The Business Case for Supplier Diversity: Why it Matters to You
Intel presentation and panel discussion
Rm 308, Esplanade

1:00 pm – 5:00 pm
From Collision to Convergence: Co-creating Soutions in the Semiconductor and MEMS/Sensors Industries
San Francisco Marriott Marquis

2:00 pm – 4:00 pm
World of IoT Innovation
Innovation and IoT Theater

3:00 pm –4:30 pm
Bulls & Bears Panel
W Hotel

200mm fabs reawakening


July 13, 2016

By David Lammers, Contributing Editor

Buoyed by strong investments in China, 200mm wafer production is seeing a re-awakening, with overall 200mm capacity expected to match its previous 2006 peak level by 2019 (Figure 1).

Figure 1. By 2019, 200mm fab capacity should be close to the previous peak seen in 2006, according to SEMI. Several new 200mm fabs are expected to open in China. (Source: SEMICON West presentation by Christian Dieseldorff).

Figure 1. By 2019, 200mm fab capacity should be close to the previous peak seen in 2006, according to SEMI. Several new 200mm fabs are expected to open in China. (Source: SEMICON West presentation by Christian Dieseldorff).

Speaking at a SEMI/Gartner market symposium at SEMICON West, SEMI senior analyst Christian Dieseldorff said over the next few years “we don’t see 200mm fabs closing, in fact we see new ones beginning operation. To me, that is just amazing.”

The numbers back up the rebound. Excluding LEDs, the installed capacity of 200mm fabs will reach about 5.3 million wafers per month (wspm) in 2018, almost matching the 2007 peak of 5.6 million wspm. As shown in Figure 1, By 2019 as new 200mm fabs start up in China, 200mm wafer production will surge beyond the previous 2007 peak, a surprising achievement for a wafer generation that began more than 25 years ago. Figure 2 shows how capacity, which held steady for years, is now on the increase.

Figure 2. 200mm fab capacity, which remained relatively constant for years, is now increasing.

Figure 2. 200mm fab capacity, which remained relatively constant for years, is now increasing.

Case in point: On the opening day of Semicon West, Beijing Yangdong Micro announced a new OLED 200mm fab that will be opening in the second half of 2018 to make OLED drivers, according to Dieseldorff.

Over the past few years, Japan-based companies have closed 10 200mm fabs, mostly outdated logic facilities, while expanding production of discrete power and analog ICs on 200mm wafers. But with China opening several new 200mm fabs and the expansions of existing 200mm fabs worldwide, SEMI sees an additional 274,000 wafer starts per month of 200mm production over the 2015-2018 period, adding expansions and additional fabs, and subtracting closed facilities.

“One message from our research is that we believe the existing 200mm fabs are full. Companies have done what they can to expand and move tools around, and that is coming to an end,” he said. SEMI reckons that 19 new 200mm fabs have been built since 2010, at least six of them in China.

SEMI’s Christian Dieseldorff.

SEMI’s Christian Dieseldorff.

Dieseldorff touched on a vexing challenge to the 200mm expansion: the availability of 200mm equipment. “People have problems getting 200mm equipment, used and even new. The (200mm) market is not well understood by some companies,” he said. With a shortage of used 200mm equipment likely to continue, the major equipment companies are building new 200mm tools, part of what Dieseldorff described as an “awakening” of 200mm manufacturing.

 

China is serious

Sam Wang, a research vice president at Gartner who focuses on the foundry sector, voiced several concerns related to 200mm production at the SEMI/Gartner symposium. While SMIC (which has a mix of 200mm and 300mm fabs) has seen consistently healthy annual growth, the five second-tier Chinese foundries – — Shanghai Huahong Grace, CSMC, HuaLi, XMC, and ASMC — saw declining revenues year-over-year in 2015. Overall, China-based foundries accounted for just 7.8 percent of total foundry capacity last year, and the overall growth rate by Chinese foundries “is way below the expectations of the Chinese government,” Wang said.

The challenge, he said, is for China’s foundries which rely largely on legacy production to grow revenues in a competitive market. And things are not getting any easier. While production of has shown overall strength in units, Wang cautioned that price pressures are growing for many of the ICs made on 200mm wafers. Fingerprint sensor ICs, for example, have dropped in price by 30 percent recently. Moreover, “the installation of legacy nodes in 300mm fabs by large foundries has caused concern to foundries who depend solely on 200 mm.”

But Wang emphasized China’s determination to expand its semiconductor production. “China is really serious. Believe it,” he said.

New markets, new demand

The smart phone revolution has energized 200mm production, adding to a growing appetite for MEMS sensors, analog, and power ICs. Going forward, the Internet of Things, new medical devices, and flexible and wearable products may drive new demand, speakers said at the symposium.

Jason Marsh, director of technology for the government and industry-backed NextFlex R&D alliance based in San Jose, Calif., said many companies see “real potential” in making products which have “an unobtrusive form factor that doesn’t alter the physical environment.” He cited one application: a monitoring device worn by hospital patients that would reduce the occurrence of bed sores. These types of devices can be made with “comparatively yesteryear (semiconductor) technology” but require new packaging and system-level expertise.

Legacy devices made on 200mm wafers could get a boost from the increasing ability to combine several chips made with different technologies into fan out chip scale packages (FO CSPs). Bill Chen, a senior advisor at ASE Group, showed several examples of FO CSPs which combine legacy ICs with processors made on leading-edge nodes. “When we started this wafer-level development around 2000 we thought it would be a niche. But now about 30 percent of the ICs used in smart phones are in wafer-level CSPs. It just took a lot of time for the market forces to come along.”

More coverage from this year’s SEMICON West can be found here.

MEMS & Sensors Industry Group (MSIG) invites attendees to a special half-day workshop on the convergence of MicroElectroMechanical Systems (MEMS) devices, sensors, flexible substrates and semiconductors in the Internet of Things (IoT) at SEMICON West on July 13, 2016. Speakers will explore the theme “From Collision to Convergence: Co-Creating Solutions in the Semiconductor and MEMS/Sensors Industry” as they address a new and necessary level of collaboration for enabling IoT and other growing applications.

“The supply chain for the IoT is complex, and navigating its dynamic ecosystem requires collaboration among stakeholders,” said Karen Lightman, executive director, MEMS & Sensors Industry Group. “By focusing on pre- and non-competitive challenges, industry players work toward common goals that benefit all — and that are only possible through collaborative effort. Attendees of the MSIG and SEMI joint workshop will get updates on the most pressing challenges to the increased use of MEMS, sensors and semiconductors in IoT applications.”

“Our joint workshop with MSIG at SEMICON West 2016 is a great forum to work together through the key convergence issues as well as to set the agenda for next steps on our shared goals,” said Denny McGuirk, president and CEO of SEMI. “SEMI and MSIG started with a joint survey on MEMS, sensors and semiconductors in early 2015 and immediately found traction among industry players. With its focus on industry realities like consolidation and the extended supply chain, this workshop takes on the key intersections and inflections.”

MSIG Chief Strategy Officer Steve Whalley and SEMI Vice President of Product Management and Business Development Bettina Weiss will co-chair the joint workshop. The agenda features:

  • Keynote: Leveraging M&A in a Converging Semiconductor and MEMS/Sensor IoT World, Greg Mischou, senior partner, Woodside Capital Partners, LLC
  • Panel discussion with panelists from:
    • A.M. Fitzgerald and Associates
    • Electronic System Design Alliance
    • FlexTech
    • Lam Research
    • Woodside Capital Partners
  • Breakout Sessions — breakout groups will report on specific actions that companies can take to address these challenges/opportunities.

MSIG and MSIG member companies will be on the show floor at SEMICON West. Visit MSIG in Booth N4 or visit http://msigevents.org/semicon-west-2016 for a list of MSIG exhibiting member companies and partners.

The MSIG and SEMI joint workshop takes place July 13, 2016 from 1:00-5:00 p.m. at the San Francisco Marriott Marquis, 780 Mission Street. Pre-registration is required: http://bit.ly/28IOUbK