Category Archives: Displays

You can’t fix what you can’t find. You can’t control what you can’t measure. 

BY DAVID W. PRICE and DOUGLAS G. SUTHERLAND

This is the first in a series of 10 installments which will discuss fundamental truths about process control—inspection and metrology—for the semiconductor industry. By fundamental, we imply the following:

  • Unassailable: They are self-evident, can be proven from first principles, or are supported by the dominant behavior at fabs worldwide
  • Unchanging: these concepts are equally true today for 28nm as they were 15 years ago for 0.25μm, and are expected to hold true in the future
  • Universal: They are not unique to a specific segment of process control; rather they apply to process control as a group, as well as to each individual component of process control within the fab

Each article in this series will introduce one of the 10 fundamental truths and discuss interesting applications of these truths to semiconductor IC fabs. Given the increasing complexity of advanced devices and process integration, process control is growing in importance. By understanding the fundamental nature of process control, fabs can better implement strategies to identify critical defects, find excursions, and reduce sources of variation.

The first fundamental truth of process control for the semiconductor IC industry is:

You can’t fix what you can’t find. You can’t control what you can’t measure.

While it’s true that inspection and metrology systems are not used to make IC devices—they do not add or remove materials or create patterns—they are critical for making high-yielding, reliable devices. By finding defects and measuring critical parameters, inspection and metrology systems monitor the hundreds of steps required to manufacture a device, ensuring the processes meet strict manufacturing specifications and helping fab engineers identify and troubleshoot process issues when there is an excursion. Without inspection and metrology, it would be near impossible for fabs to pinpoint process issues that affect yield. However, it’s not enough to simply “find” and “measure” — a fab’s process control strategy needs to be capable and cost-effective.

Capable inspection and metrology strategies find and measure the defects and parameters that affect device yield. Cost-effective inspection and metrology is performed at the lowest total cost to the factory, where total cost is the sum of the cost of lost yield plus the cost of process control.

First, make it capable

If you can’t find it, you can’t fix it. At the heart of this truth is the understanding that, above all else, a fab’s inspection and metrology strategy must be capable. It must highlight the problems that are limiting baseline yield. It must also provide actionable information that can enable fabs to quickly find and fix excursions (FIGURE 1).

We emphasize this need for capability first because we have observed that some fabs are too quick tosacrifice capability for cost reductions. No strategy is cost-effective if it doesn’t accomplish its fundamental objective.

Below are specific questions that can help fab management evaluate the capability of its process control strategy:

  • Are you finding all sources of your defect-limited yield? Are you finding these in-line or at end-of-line?
  • Does your defect Pareto have sufficient resolution of the top yield-limiters in each module to direct the most appropriate use of factory engineering resources?
  • Have you fully characterized all of the important measurements and defect types (size range, kill ratio, root cause, solution)?
  • Do you understand the most probable incursion scenarios? What is the smallest excursion that you absolutely must detect at this step? How many lots are you willing to have exposed to this excursion before it is detected?
  • Are you inspecting and measuring at all the right steps? Can you quickly isolate the point of formation for excursions? Can you quickly disposition potentially affected lots?
  • Does a particular defect signature become confused by defects added at subsequent process steps? Or do you need separate inspections at each step in order to partition the problem? 
  • Do you have overlapping inspections to guard against the high-frequency, high-impact excursions?
  • What is the alpha risk and beta risk for each inspection or measurement? How are these related to the capture rate, accuracy, precision, matching and more?

Process control Fig 1b Process control fig 1a

 

FIGURE 1. You can’t fix what you can’t find. And you can’t control what you can’t measure. Left: P-MOS SiGe critical dimension measurement. Right: Fin patterning particle leading to a Fin Spire defect at post dummy gate etch. Source: KLA-Tencor

Then, make it cost-effective

Once a capable strategy is in place, then a fab can start the process of making it cost-effective. The best known method for optimizing total cost is usually adjusting the overall lot sampling rate. This is generally preferred because the capability remains constant.

In some cases, it may be possible to migrate to a less sensitive inspection (lower cost of ownership tool or larger pixel size); however, this is a dangerous path because it re-introduces uncertainty (alpha/beta risk) that reduces a fab’s process control capability. This concept will be discussed in more detail in our next article on sampling strategies.

Finally, it is worth pointing out that it is not enough to implement a capable strategy. The fab must ensure that what was once a capable strategy, stays a capable strategy. A fab cannot measure with a broken inspection tool or trust a poorly maintained inspection tool. Therefore, most fabs have programs in place to maintain and monitor the ongoing performance of their inspection and metrology tools.

By optimizing process control strategy to be capable and cost-effective, fabs ultimately find what needs to be fixed and measure what should be controlled—driving higher yield and better profitability.

SEMI, the global industry association for companies that supply manufacturing technology and materials to the world’’s chip makers, today reported that worldwide semiconductor manufacturing equipment billings reached US$ 9.62 billion in the second quarter of 2014. The billings figure is 5 percent lower than the first quarter of 2014 and 28 percent higher than the same quarter a year ago. The data is gathered jointly with the Semiconductor Equipment Association of Japan (SEAJ) from over 100 global equipment companies that provide data on a monthly basis.

Worldwide semiconductor equipment bookings were $9.96 billion in the second quarter of 2014. The figure is 9 percent higher than the same quarter a year ago and 1 percent higher than the bookings figure for the first quarter of 2014.

The quarterly billings data by region in billions of U.S. dollars, quarter-over-quarter growth and year-over-year rates by region are as follows:


Region


2Q2014


1Q2014


2Q2013

2Q14/1Q14
(Qtr-over-Qtr)

2Q14/2Q13
(Year-over-Year)
Taiwan

2.48

2.59

2.73

-5%

-9%
North America

2.32

1.85

1.16

25%

101%
Korea

1.73

2.03

1.22

-15%

42%
China

1.03

1.71

0.84

-40%

23%
Japan

1.00

0.96

0.74

4%

35%
Europe

0.57

0.58

0.36

-3%

58%
ROW

0.50

0.42

0.51

18%

-2%
Total

9.62

10.15

7.54

-5%

28%

Source: SEMI/SEAJ September 2014

Note: Figures may not add due to rounding.

BY TOM QUAN, Deputy Director, TSMC

The Prophets of Doom greet every new process node with a chorus of dire warnings about the end of scaling, catastrophic thermal effects, parasitics run amok and . . . you know the rest. The fact that they have been wrong for decades has not diminished their enthusiasm for criticism, and we should expect to hear from them again with the move to 10nm design.

Like any advanced technology transition, 10nm will be challenging, but we need it to happen. Design and process innovation march hand in hand to fuel the remarkable progress of the worldwide electronics industry, clearly demonstrated by the evolution of mobile phones since their introduction (FIGURE 1).

FIGURE 1. The evolution of mobile phones since their introduction.

FIGURE 1. The evolution of mobile phones since their introduction.

Each generation gets harder. There are two different sets of challenges included with a new process node: the process technology issues and the ecosystem issues.

Process technology challenges include:

  • Lithography: continue to scale to 193nm immersion
  • Device: continue to deliver 25-30% speed gain at the same or reduced power
  • Interconnect: address escalating parasitics
  • Production: ramp volume in time to meet end-customer demand
  • Integration of multiple technologies for future systems

Ecosystem challenges include:

  • Quality: optimize design trade-off to best utilize technology
  • Complexity: tackle rising technology and design complexity
  • Schedule: shortened development runway to meet product market window

Adding to these challenges at 10nm is that things get a whole lot more expensive, threatening to upset the traditional benefits of Moore’s Law. We can overcome the technical hurdles but at what cost? At 10nm and below from a process point of view, we can provide PPA improvements but development costs will be high so we need to find the best solutions. Every penny will count at 7nm and 10nm.

FIGURE 2. A new design ecosystem collaboration model is needed due to increasing complexity and shrinking development runways.

FIGURE 2. A new design ecosystem collaboration model is needed due to increasing complexity and shrinking development runways.

Design used to be fairly straightforward for a given technology. The best local optimum was also the best overall optimum: shortest wire length is best; best gate-density equates to the best area scaling; designing on best technology results in the best cost. But these rules no longer apply. For example, sub-10nm issues test conventional wisdom since globalized effects can no longer be resolved by localized approaches. Everything has to be co-optimized; to keep PPA scaling at 10nm and beyond requires tighter integration between process, design, EDA and IP. Increasing complexity and shrinking development runways call for a new design ecosystem collaboration model (FIGURE 2).

Our research and pathfinding teams have been working on disruptive new transistor architectures and materials beyond HKMG and FinFET to enable further energy efficient CMOS scaling. In the future, gate-all-around or narrow wire transistor could be the ultimate device structure. High mobility Ge and III-V channel materials are promising for 0.5V and below operations.

Scaling in the sub-10nm era is more challenging and costly than ever, presenting real opportunities for out-of-box thinking and approaches within the design ecosystem. There is also great promise in wafer-level integration of multiple technologies, paving the way for future systems beyond SoC.

A strong, comprehensive and collaborative ecosystem is the best way to unleash our collective power to turn the designer’s vision into reality.

NVIDIA today announced that it has filed complaints against Samsung and Qualcomm at the International Trade Commission and in the U.S. District Court in Delaware, alleging that the companies are both infringing NVIDIA GPU patents covering technology including programmable shading, unified shaders and multithreaded parallel processing.

The identified Samsung products include the Galaxy Note Edge, Galaxy Note 4, Galaxy S5, Galaxy Note 3 and Galaxy S4 mobile phones; and the Galaxy Tab S, Galaxy Note Pro and Galaxy Tab 2 computer tablets. Most of these devices incorporate Qualcomm mobile processors — including the Snapdragon S4, 400, 600, 800, 801 and 805. Others are powered by Samsung Exynos mobile chips, which incorporate ARM’s Mali and Imagination Technologies’ PowerVR GPU cores.

NVIDIA co-founder and CEO Jen-Hsun Huang said: “NVIDIA has invented technologies that are vital to mobile computing. We have the richest portfolio of computer graphics IP in the world, with 7,000 patents granted and pending, produced by the industry’s best graphics engineers and backed by more than $9 billion in R&D.

“Our patented GPU inventions provide significant value to mobile devices. Samsung and Qualcomm have chosen to use these in their products without a license from us. We are asking the courts to determine infringement of NVIDIA’s GPU patents by all graphics architectures used in Samsung’s mobile products and to establish their licensing value.”

A pioneer in computer graphics, NVIDIA invented the GPU. The graphics processing unit enables computers to generate and display images. It brings to life the beautiful graphics that shape how people enjoy their mobile devices and is fundamental to the rise of mobile computing. NVIDIA GPUs are some of the most complex processors ever created, requiring over a thousand engineering-years to create and containing more than 7 billion transistors.

Bend them, stretch them, twist them, fold them: modern materials that are light, flexible and highly conductive have extraordinary technological potential, whether as artificial skin or electronic paper.

Making such concepts affordable enough for general use remains a challenge but a new way of working with copper nanowires and a PVA “nano glue” could be a game-changer.

Previous success in the field of ultra-lightweight “aerogel monoliths” has largely relied on the use of precious gold and silver nanowires.

By turning instead to copper, both abundant and cheap, researchers at Monash University and the Melbourne Centre for Nanofabrication have developed a way of making flexible conductors cost-effective enough for commercial application.

“Aerogel monoliths are like kitchen sponges but ours are made of ultra fine copper nanowires, using a fabrication process called freeze drying,” said lead researcher Associate Professor Wenlong Cheng, from Monash University’s Department of Chemical Engineering.

“The copper aerogel monoliths are conductive and could be further embedded into polymeric elastomers – extremely flexible, stretchable materials – to obtain conducting rubbers.”

Despite its conductivity, copper’s tendency to oxidation and the poor mechanical stability of copper nanowire aerogel monoliths mean its potential has been largely unexplored.

The researchers found that adding a trace amount of poly(vinyl alcohol) (PVA) to their aerogels substantially improved their mechanical strength and robustness without impairing their conductivity.

What’s more, once the PVA was included, the aerogels could be used to make electrically conductive rubber materials without the need for any prewiring. Reshaping was also easy.

“The conducting rubbers could be shaped in arbitrary 1D, 2D and 3D shapes simply by cutting, while maintaining the conductivities,” Associate Professor Cheng said.

The versatility extends to the degree of conductivity. “The conductivity can be tuned simply by adjusting the loading of copper nanowires,” he said. “A low loading of nano wires would be appropriate for a pressure sensor whereas a high loading is suitable for a stretchable conductor.”

Affordable versions of these materials open up the potential for use in a range of new-generation concepts: from prosthetic skin to electronic paper, for implantable medical devices, and for flexible displays and touch screens.

They can be used in rubber-like electronic devices that, unlike paper-like electronic devices, can stretch as well as bend. They can also be attached to topologically complex curved surfaces, serving as real skin-like sensing devices, Associate Professor Cheng said.

In their report, published recently in ACS Nano, the researchers noted that devices using their copper-based aerogels were not quite as sensitive as those using gold nanowires, but had many other advantages, most notably their low-cost materials, simpler and more affordable processing, and great versatility.

SEMI today announced the keynotes for the 2nd Vietnam Semiconductor Strategy Summit(September 16-17), an executive conference focused on Vietnam’’s growing role in the global semiconductor industry. The executive event held at the InterContinental Asiana Saigon Hotel in Ho Chi Minh City, brings together key decision-makers shaping the future of the industry in Vietnam, and international participants from major companies in the semiconductor manufacturing supply chain.  Keynote presentations include Sherry Boger, Vietnam general manager, Intel Corporation, and Pham B Tuan, CNS, who will both provide their perspectives on current and future industry development in Vietnam.

In total for 2014 and 2015, SEMI estimates a spending of almost $4 billion on front-end and back-end equipment in the Southeast Asia region, and another $13 billion in spending on materials including $3 billion on fab related materials. In addition, according to the SEMI World Fab Forecast, Southeast Asia is home to over 35 production fabs covering Foundry, Compound Semiconductors, MEMS, Power, LED, and other devices. Specific to backend manufacturing, Gartner reports that the Southeast Asia microelectronics manufacturing market accounts for 27 percent of the world’s assembly, packaging, and test production square footage.

At this year’s summit, executives from leading microelectronics companies —and semiconductor equipment and materials companies — will meet with delegates representing Vietnamese government, academia, research, and industry to explore and discuss the key strategies and opportunities in the growing Vietnam semiconductor industry. The event includes:

  • Market Overviews: Presentations by Bettina Weiss, SEMI Headquarters and Clark Tseng, SEMI Taiwan
  • Semiconductor Manufacturing in Vietnam: Presentations by: Sherry Boger, Intel; Pham B Tuan, CNS; Solomon Ng, STMicroelectronics; Todd Curtis, Fab-Finder; and Cor Claeys, imec
  • Two Panel Discussions: Investor Perspectives (moderated by Eduard Hoeberichts, FabMax) and Education and Workforce Development (moderated by Bettina Weiss, SEMI)
  • Tabletop exhibition and discussions

“Vietnam is committed to the global microelectronics world and moving beyond backend,” said Kai Fai Ng, president SEMI Southeast Asia. As the first major new fab project in Vietnam, many challenges still remain, from infrastructure and process technology to device design and IP creation and protection. The SEMI Vietnam event provides a key platform to advance important discussions and decision-making in this promising and growing market.”

The connections and relationships forged during the Summit are expected to drive further growth over the next decade and beyond. Global stakeholders with an interest in Vietnam’’s semiconductor market, including those from the equipment, materials, and device and R&D communities, are invited to share their vision, insights and outlook with Vietnam’s local business, technology and educational communities.

The 2nd SEMI Vietnam Semiconductor Strategy Summit is organized by SEMI and co-organized by Saigon Hi-Tech Park (SHTP) and Ho Chi Minh City Semiconductor Industry Association (HSIA).  The premier sponsor is FabMax. Individual registration costs US$750 for SEMI members and US$950 for non-members. Registration and additional information is available online at www.semi.org/vietnam.

The Plastics Electronics Conference and Exposition will co-locate with SEMICON Europa. Plastic Electronics 2014 (PE 2014) is themed “Enabling Applications beyond Limits in Electronics” and will be held at Alpexpo in Grenoble on 7-9 October. PE2014 is an ideal forum to meet technology leaders and professionals from industry, academia, and research organizations focused on developing the next-generation of plastic and organic electronics.

According to analysts, the plastics electronics market is growing rapidly and is expected to reach $13 billion by 2020 driven by increasing applications in the semiconductor and electronics market. Applications like large area displays, solar panels and printed electronics are now responsible for a substantial portion of the PE market, and emerging applications like OLED, thin-film batteries, and sensors are emerging growth opportunities.

Manufacturability of Plastic Electronics has made major steps in the last year, moving from research level to industrial relevance.  Still, numerous barriers to commercialization must be overcome — from material development to integration, manufacturing, processing, and assembly issues. PE2014 covers these issues currently driving development and impeding progress.

Plastic electronics’ imminent transition from the R&D phase to the industrialization stage is highlighted by several keynote presentations at the PE2014 (www.plastic-electronics.org).  Fiddian Warman, founder and managing director, SODA, will present on, “How design type approaches can be effective in facilitating innovative technological development and open up new markets and opportunities,” and John Heitzinger, president, Soligie, Inc., will delve into “Advances in Additive Manufacturing of Electronics.”

The exposition and conference cover the entire span of Plastic Electronics —Hybrid and Heterogeneous Integration; Organic Electronics; OLEDs, Displays, and Lighting; and Flexible Photovoltaics — offering the latest developments for engineers, material experts, manufacturing professionals and industry strategists. Highlights are:

  • Business Case session —  speakers from imec, ISORG, Nokia, Philips Research, Plastic Logic, SODA, STMicroelectronics, Valeo, and Yole Developpement.
  • Manufacturing Panel Discussion on “Building a Leadership Position in PE” — panelists from Bosch, Cambridge, CEA, Joanneum Research, and Ynvisible.
  • Manufacturing Session — presenters from Applied Materials, Beneque, CEA Tech, Dupont Teijin Films UK Ltd, Joanneum Research, NovaCentrix, Roth and Rau B.V.,  Soligie, Universal Laser Systems, Ynvisible — as well as Cambridge University, the European Commission, and VTT (Finland).
  • Technologies/Materials Session — features speakers from Arkema, Arizona State University, CEA-LITEN, Corning, Fraunhofer, imec, and Sunchon National University.

The Plastic Electronics Exhibition & Conference 2014 is hosted by SEMI and representatives of leading industry companies, research centers and institutes. SEMI focuses its activities on roadmaps, standardization, research and statistics, conferences, exhibitions and public policy worldwide.  For more information on the conference, presenters, topics, events and exhibitors, visit www.plastic-electronics.org.

During the three days of SEMICON Europa 2014 (www.semiconeuropa.org), more than 8,000 visitors from all over the world are expected at the trade fair. The combination of SEMICON Europa with Plastic Electronics offers visitors and exhibitors excellent synergies and opportunities.

MarketResearchReports.Biz released a new market research report this week entitled “Metal Oxide TFT Backplanes For Displays 2014-2024: Technologies, Forecasts, Players.”

According to the new report, metal oxide display backplanes have already gone commercial. Sharp has invested in establishing a Gen8 IGZO plant at its Kameyama plant in Japan while LG has also selected IGZO backplanes for its large-sized white OLED technology. At the same time, Chinese companies such as BOE are fast playing catch up with both prototype and production capacity announcements.

IDTechEx estimates that 7 km sqr of metal oxide backplanes will be used in the OLED industry in 2024, enabling a 16 billion USD market at the display module level. The LCD display market will add an extra demand of at least 1 km sqr per year in 2024 for metal oxide backplanes.

The display industry continues to rapidly change and seek new markets. Long term trends are still prevalent and shape global activity. Examples include reducing power consumption, improving image resolution, and decreasing device thickness. At the same, the need to differentiate and capture new markets such as wearable electronics is first bringing in robust and then flexible and bendable displays. These trends will drastically affect the technology requirements at many levels including the backplane level. This will stretch several existing solutions beyond likely performance limits, thereby creating openings and opportunities for new entrants and the technology space for backplanes is complex. It consists of (a) mature technologies such as amorphous and polycrystalline silicon, (b) emerging technologies such as organic and metal oxides and (c) early state technologies such as graphene, carbon nanotubes, nanowires, etc. No single technology offers a one-size-fits-all solution and many technologies will co-exist in the market. Betting on the right technology will remain a decision-making nightmare.

It is within this emerging, complex yet changing space that metal oxide are emerging. They promise low leakage currents, high mobility, amorphousity, stability and wide bandgap. These attributes promise to enable, respectively, power consumption reduction, compatibility with current-driven OLEDs and/or 3D displays, image uniformity over large areas, long lifetime and transparency.

In the short term, this will help enable higher resolution and lower power consumption levels in displays including LCDs (particularly in medium- to large-sized displays); while in the medium- to long-term metal oxides will help enable uniform medium- to large-sized OLED displays.

The report specifically addresses the big picture – including OLED displays and lighting, to thin film photovoltaics to flexible sensors and much more. Importantly, it includes not only electronics which are printed, organic and/or flexible now, but it also covers those that will be. Realistic timescales, case studies, existing products and the emergence of new products are given, as are impediments and opportunities for the years to come.

Over 3,000 organizations are pursuing printed, organic, flexible electronics, including printing, electronics, materials and packaging companies. While some of these technologies are in use now – indeed there are three sectors which have created billion dollar markets – others are commercially embryonic.

Electro Scientific Industries, Inc., a supplier of innovative laser-based manufacturing solutions for the microtechnology industry, today announced that Richard H. Wills, former Chairman and Chief Executive Officer of Tektronix, Inc., was appointed to the company’s Board of Directors.

Mr. Wills was President and CEO of Tektronix from 2000 until 2008, and its Chairman from 2001 through 2008. He joined Tektronix in 1979 and served in a range of marketing, product development and management roles, including President of the Measurement Business and President of Regional Operations for both Europe and the Americas. He holds a master’s degree in business administration from the University of Oregon and a bachelor’s degree in computer systems from Linfield College.

“Rick brings a wealth of technology and management experience, and his marketing background will be of great benefit as we transform ESI into a more market-focused organization. We look forward to benefiting from Rick’s insight and leadership,” said Edward C. Grady, Chief Executive Officer of ESI.

“I am honored to join the ESI board and to work with this excellent team,” Wills said. “ESI has been a leader in laser technology for many years, and I look forward to contributing to the future direction and growth of this global leader.”

ESI is a supplier of innovative, laser-based manufacturing solutions for the microtechnology industry. Their systems enable structuring and testing of micron to submicron features in smart consumer electronics, semiconductors, LEDs and other high-value components.

Himax Technologies, Inc., a supplier and fabless manufacturer of display drivers and other semiconductor products, and Lumus, a producer of Augmented Reality glasses, announced today another joint initiative to continue developing the next-generation of smart glasses that will set new technological standards in image quality and performance.

Commenting on the partnership, Jordan Wu, President and Chief Executive Officer of Himax, stated, “We are very excited to expand our existing partnership with Lumus. They have developed an innovative technology, which will enable Augmented Reality glasses to become the next ‘must-have’ consumer device.”

According to Zvi Lapidot, Chief Executive Officer of Lumus, “Himax’s superior LCOS technology, its availability for high volume production, and the Company’s forward looking technological applications were critical in our selection of Himax as a strategic partner. Their microdisplay, specifically designed for smart glasses, combines smoothly with Lumus’ transparent display, creating the ideal solution for true Augmented Reality and hands-free wearable computing.”

Mr. Lapidot added, “While our ultra-thin, see-through optics enable natural looking wearable displays, Himax’s unique LCOS technology provides the high level of brightness necessary for see-through Augmented Reality. Ultimately, our cooperation enables us to bring widely appealing solutions to help seamlessly and intuitively blend wearable technology into our daily lives.”

Himax and Lumus have been successfully collaborating for several years in the field of combat aviation, producing market leading helmet mounted displays. Leveraging their combat-proven solutions and manufacturing capabilities, the two companies are now collaborating to make wearable displays mainstream consumer products.