Category Archives: LEDs

September 7, 2007 – Oki Electric Industry Co. Ltd. and Oki Printing Solutions (aka Oki Data Corp.) say they have achieved volume production of LED array chips for LED printheads using a new “epi film bonding” (EFB) technology, in which thin films are released and bonded on dissimilar materials. The technology also shows promise in manufacturing lower-cost and higher-density compound semiconductor devices.

In conventional LED printheads, LED array chips and IC driver chips are mounted on a printed circuit board and connected by bonding wires, but high-density wire bonding and large bonding pads limit the density of LED arrays and printing resolutions. The new technology bonds LED array chips with the wafer by utilizing the intermolecular bonding force, enabling higher-density and higher-layer devices. Oki also said it has made progress shrinking the size of the driver ICs and LED array chips, reducing the density of bonding wires, and reducing the number of chips.

Mikihiko Maeno, President and CEO of Oki Data Corp., indicated a 600dpi LED printhead made with the EFP technology has half the volume of conventional LED printheads. The devices are being packaged in color and monochrome LED printers planned for shipment, with plans to develop ultrasmall printheads (}gte 1200dpi) for higher-resolution printing.

Oki Electric, meanwhile, plans to push the EFB technology toward use in smaller, lower-power consumption and lower-cost semiconductor ICs, where it can eliminate wire bonding and die-bonding processes, enabling manufacturing of higher-density compound devices using only photolithography processes. The company also plans to apply EFB to super-small LED displays.

“EFB technology enables us to make higher density, multi-layered, faster speed, and lower power consumption semiconductors, which brings possibilities in developing various compound circuit ICs,” stated Harushige Sugimoto, SVP and CTO at Oki Electric. He said the company is also looking at ways to apply the technology beyond semiconductors, to bond dissimilar materials.

NanoCon Newswire

Aug. 24, 2006 (Emeryville, Calif.) — Nanomix Inc., a leading nanoelectronic detection company commercializing high-value diagnostic and monitoring applications, today announced the appointment of Dr. Michael D. Cable as Vice President, Platform Development to lead the company’s efforts in detection platform optimization for a variety of applications. In this position, Dr. Cable will report to David Macdonald, President and Chief Executive Officer.

Dr. Cable has over 20 years experience with a broad range of instrumentation and detection technologies related to medical diagnostic and monitoring applications. After earning a BS in Chemistry and Physics from Iowa State University, Dr. Cable obtained his Ph.D. from University of California Berkeley in Nuclear Chemistry and Physics. He has published extensively and holds multiple patents.

Prior to joining Nanomix, Dr. Cable was Vice President, Research and Development at Fovi Optics where he was involved with non-invasive glucose detection. He has been a consultant to Quantum Dot Corporation and held the position of Vice President and Chief Technology Officer at Xenogen. Dr. Cable has also held positions of increasing responsibility at the University of Rochester and Lawrence Livermore National Laboratory.

“We are thrilled with the addition of Mike to our management team,” said Nanomix CEO David Macdonald, “He will further enhance our detection platform and our ability to effectively execute project plans.”

About Nanomix

Nanomix is a leading nanoelectronic detection company launching a portfolio of devices based on Sensation™ technology. These scaleable devices use ultra-sensitive carbon nanotube detection elements combined with proprietary chemistries. They can be deployed across a broad range of industrial and medical applications where valuable attributes – low power consumption, small size, and high sensitivity offer significant performance advantages and enable unprecedented access to critical information. Nanomix is located in Emeryville, California. For additional information, please visit the Nanomix web site at www.nano.com

By Genevieve Oger
Small Times Contributing Editor

Sept. 5, 2006 — The French city of Toulouse is an aerospace town. The headquarters of Airbus and the French National Center for Space Studies are nearby, as is Aerospace Valley, a French cluster of hundreds of companies and state bodies focused on space. It’s an appropriate place to hold the third CANEUS conference, a bi-annual forum designed to help transform micro and nanotechnologies into real-life aerospace applications.

CANEUS is an acronym for Canada, Europe and the United States — the regions that launched the initiative five years ago. Asia and Brazil have since joined, though the acronym has remained unchanged. The group came out of a frustration many aerospace scientists were struggling with. Labs around the world were wasting resources by working on the same projects, each reinventing the wheel in their own way.

That wasn’t the only problem, according to CANEUS co-founder Thomas George, a director at software firm Vialogy. “I had been working at (NASA’s) Jet Propulsion Laboratory, where we had developed 25 technologies, of which only one had made it successfully to mission,” he said, adding that micro and nanotech innovations in particular face Darwinian odds. “Out of 100 good concepts, less than one percent will make it to product — not because of technological flaws, but because the inventor isn’t savvy enough to raise money, to create a system level product, or (he or she) lacks marketing skills.”

The group’s founders realized that the great majority of micro and nano innovations never get beyond the initial phase. The concepts and principles might have been proven and the ideas might work. But the innovations have to be put into a system that will work with the rest of the aircraft. The unit must be tested for reliability on the ground and then in space. The great majority of innovations get stuck in this very expensive mid-development stage — the so-called “valley of death” applications must get through before making it onto a real flight mission.

The conference in Toulouse, held Aug. 27 to Sept. 1, was organized in three parts — First a short course briefing people on systems and different aspects of international collaborations, then a conference detailing what different experts are doing around the world, followed by two days of workshops. “The workshops are where we get to the meat of it, where we get to the business plans, look at end users,” George said. “All in enough detail to present a well-thought-out project to the guys with the money.” The focus of the workshops is on getting developers to work on projects end-users actually need and are willing to pay for. That way, traversing the perilous valley will be as quick as possible.

Xavier Lafontan is the manager of Nova Mems, a Toulouse area company that performs reliabilities tests on micro and nanotechnologies for their customers, which include Alcatel Alenia Space, MEMS-maker Memscap and industrial conglomerate Siemens. He says that the aeronautics industry is a particularly challenging environment in which to integrate new technologies. “At first glance it seems like a big market, but when you look closer you realize the components are extremely diverse and that the market for each product is actually quite small — making development costs very steep,” Lafontan said.

In addition, the aeronautics industry has very specific requirements — an aircraft has to last 30 years and components have to function in extremely harsh conditions — making it even more expensive. “So there is certainly a need for this type of gathering to identify where the sticking points are and how we can get beyond them together.”

Extreme conditions and product life aren’t the only reason why it’s tougher to break into the aeronautics industry, compared to, for example, cars or clothing. The United States still considers space a strategic interest and ITAR (International Traffic in Arms Regulations) concerns can sometimes prevent many international collaborations from getting off the ground. This obstacle leads some to think that this type of collaboration can never fully succeed. “Nothing is impossible,” said Alcatel Space’s Augustin Coello-Vera, “because there’s collaboration on the International Space Station, but it’s certainly very difficult.”

Despite the various constraints of the aerospace industry, a few success stories are beginning to emerge. One of the workshops of the 2004 conference in Monterrey led to a partnership on nanocomposite materials that was later funded by Lockheed Martin. The U.S. military contractor is now in the process of building the F-35 Lightning II, a fighter aircraft for the U.S. and British governments. CANEUS Chairman Milind Pimprikar says the new plane is scheduled to be equipped with this nanocomposite material. “It was one of the concepts presented in the workshops of the 2004 conference and now the project is moving ahead.” This year, the Japanese Aerospace Exploration Agency committed to funding about one fifth of a miniature satellite project presented at one of the workshops.

The Technologies Reliability workshop at the 2006 event looked at setting up international standards for testing small technologies in space. One of the greatest barriers to using new technologies in flight missions is that the stakes are so high that space agencies or satellite companies don’t want to take any risks with new components or materials.

David Openheimer, chief scientist for Tennessee-based venture capital group Capri Partners says this remains one of the greatest barriers to developing new space applications. “Without an international standard for tests and evaluation of parts in space, the likelihood that an end-user will use those parts is very low,” he said, explaining that the existence of internationally-recognized testing standards could build confidence in this area, without much chance of ITAR issues cropping up.

September 1, 2006 – ASAT Holdings Ltd. has appointed Tung Kok Li as acting CEO effective immediately, succeeding Robert Gange who has resigned citing personal reasons, but will serve as a consultant during a transition period. Meanwhile, board member Kei Chua will serve as acting CFO while the company continues to search for a permanent CFO (Gange held the position from 2002-2005).

Li was previously chairman of ASAT’s board of directors, of which he has been a member since 1999. Gange was promoted to CEO in Aug. 2005, replacing Harry Rozakis, and led the company’s transition of manufacturing from Hong Kong to new facilities in mainland China.

ASAT also has appointed Joseph Martin as EVP of sales and marketing; he was formerly CEO of QPL International Holdings, with prior tenure at ASAT as SVP and COO. In addition, the company also has replaced one of its directors: Andrew Liu, a board member since October 1999, has resigned, replaced by Peter Hopper, a senior advisor to the CCMP Capital Asia group, and former exec with Philips Electronics.

R&D UPDATES


September 1, 2006

IBM researchers demo molecular switch

ZURICH, Switzerland – Scientists at the IBM Zurich Research Laboratory have demonstrated how a single molecule can be switched between two distinct conductive states, which allows it to store data.

The experiments, first published in the journal SMALL, show that certain types of molecules reveal intrinsic molecular functionalities that are comparable to devices used in today’s semiconductor technology.

Researchers Heike Riel and Emanuel Lörtscher reported that, using a sophisticated mechanical method, they were able to establish electrical contact with an individual molecule to demonstrate reversible and controllable switching between two distinct conductive states.

The investigation is part of their work to explore and characterize molecules to become possible building blocks for future memory and logic applications. By applying voltage pulses to the molecule, it can be controllably switched between two distinct “on” and “off” states. The researchers found that both states were stable and could therefore enable non-volatile memory. They documented more than 500 switching cycles and switching times in the microsecond range.


The SEM image is of a metallic bridge. Atomic-sized tips (which serve as electrodes) are created by stretching and breaking the bridge. The switching molecule is then “caught” between the electrodes by closing the bridge gradually until a single molecule reaches between both electrodes. Image courtesy of IBM
Click here to enlarge image

In order to individually address the molecules, Riel and Lörtscher extended a method called the mechanically controllable break-junction. With this technique, a metallic bridge on an insulating substrate is carefully stretched by mechanical bending. Ultimately the bridge breaks, creating two separate electrodes that possess atomic-sized tips.

Then a solution of the organic molecules is deposited on top of the electrodes. As the junction closes, a molecule capable of chemically bonding to both metallic electrodes can bridge the gap. In this way, an individual molecule is “caught” between the electrodes, and measurements can be performed.

The molecules investigated are specially designed organic molecules measuring about 1.5 nm. The molecules were designed and synthesized by Professor James Tour and co-workers at Rice University.

Nano-etched cavity brightens up LEDs

GAITHERSBURG, Md. – Researchers at the National Institute of Standards and Technology (NIST) have made semiconductor light-emitting diodes (LEDs) more than seven times brighter by etching nanoscale grooves in a surrounding cavity to guide scattered light.

Semiconductor LEDs typically emit only about two percent of their light in the desired direction: perpendicular to the diode surface. Far more light skims uselessly below the surface of the LED, because of the extreme mismatch in refraction between air and the semiconductor. The NIST nanostructured cavity boosts useful LED emission to about 41 percent and may be cheaper and more effective for some applications than conventional post-processing LED shaping and packaging methods that attempt to redirect light.


Etched nanostructured rings around an LED can make it more than seven times brighter. Image courtesy of NIST
Click here to enlarge image

The NIST team fabricated their own infrared LEDs consisting of gallium arsenide packed with quantum dots of assorted sizes made of indium gallium arsenide. The LEDs were backed with an alumina mirror to reflect the light emitted backwards. The periphery of each LED was turned into a cavity etched with circular grooves, in which the light reflects and interferes with itself in an optimal geometry.

The researchers experimented with different numbers and dimensions of grooves. The brightest output was attained with 10 grooves, each about 240 nm wide and 150 nm deep, and spaced 40 nm apart. The team spent several years developing the design principles and perfecting the manufacturing technique. The principles of the method are transferable to other LED materials and emission wavelengths, as well as other processing techniques, such as commercial photolithography, according to lead author Mark Su. The research was published in Applied Physics Letters.

Researchers pencil in plans for new composite

EVANSTON, Ill. – Northwestern University researchers have developed a process that could enable new composite, or graphene-based, materials.

The method uses graphite to produce individual graphene-based sheets with useful physical, chemical and barrier properties that could be mixed into materials such as polymers, glasses and ceramics.

“This research provides a basis for developing a new class of composite materials for many applications, through tuning of their electrical and thermal conductivity, their mechanical stiffness, toughness and strength, and their permeability to flow various gases through them,” said Rod Ruoff, professor of mechanical engineering in the McCormick School of Engineering and Applied Science, in a prepared statement. “We believe that manipulating the chemical and physical properties of individual graphene-based sheets and effectively mixing them into other materials will lead to discoveries of new materials in the future.”

The team’s approach was based on chemically treating and thereby “exfoliating” graphite to individual layers which are expected to display the in-plane properties of graphite. The research was published in the journal Nature.

Scientists build magnetic semiconductors one atom at a time

PRINCETON, N.J. – a team of scientists from Princeton University, the University of Illinois at Urbana-Champaign and the University of Iowa has turned semiconductors into magnets by the precise placement of metal atoms within a material from which chips are made. The team used their method to make a semiconductor magnetic, one atom at a time.

By incorporating manganese atoms into the gallium arsenide semiconductor, the team has created an atomic-scale laboratory in which researchers can explore the precise interactions among atoms and electrons in chip material. The team used their new technique to find the optimal arrangements for manganese atoms that can enhance the magnetic properties of gallium arsenide.


Substitution of magnetic atoms (manganese) into a semiconductor (gallium arsenide) creates a material for future electronics. Spins of the magnetic atoms interact via a cloud of electrons, which can be visualized using a scanning tunneling microscope. The image is a composite of microscopic visualization of electron cloud together with a model of the gallium arsenide crystal structure. Image courtesy of A. Yazdani/Princeton University
Click here to enlarge image

“Using the tip of a scanning tunneling microscope, we can take out a single atom from the base material and replace it with a single metal that gives the semiconductor its magnetic properties,” said Yazdani, a Princeton professor of physics, in a prepared statement.

The arrangement of manganese atoms that exhibits magnetic properties is an important factor in developing spin-based electronics. The research was published in the journal Nature.

Study shows catalytic activity of gold can be tuned

ATLANTA – Researchers at the Georgia Institute of Technology have made a discovery that could allow scientists to exercise more control over the catalytic activity of gold nanoclusters.

The researchers found that the dimensionality and structure, and thus the catalytic activity, of gold nanoclusters changes as the thickness of their supporting metal-oxide films is varied.

“We’ve been searching for methods for controlling and tuning the nanocatalytic activity of gold nanoclusters,” said Uzi Landman, director of the Center for Computational Materials Science and Regents’ professor and Callaway chair of physics at Georgia Tech, in a prepared statement. “I believe the effect we discovered, whereby the structure and dimensionality of supported gold nanoclusters can be influenced and varied by the thickness of the underlying magnesium-oxide film may open new avenues for controlled nanocatalytic activity.”


Structures of a gold cluster (depicted by yellow spheres) containing 20 atoms, adsorbed on a magnesium oxide bed (magnesium in green and oxygen in red) which is itself supported on top of a molybdenum substrate (blue spheres). The excess electronic charge at the interface is depicted in pink and the charge depletion is shown in light blue. Image courtesy of Uzi Landman/Georgia Tech
Click here to enlarge image

Landman’s group found that by using a thin catalytic bed with a thickness of up to 1 nm, or 4 to 5 layers, of magnesium oxide, one may activate the gold nanoclusters which may act then as catalysts even if the bed is defect-free. In the study, the researchers simulated the behavior of gold nanoclusters containing eight, sixteen and twenty atoms when placed on catalytic beds of magnesium oxide with a molybdenum substrate supporting the magnesium oxide film. Quantum mechanical calculations showed that when the magnesium oxide film was greater than 5 layers or 1 nm in thickness, the gold cluster kept its three-dimensional structure. However, when the film was less than 1nm, the cluster changed its structure and lied flat on the magnesia bed – wetting and adhering to it.

The gold flattens because the electronic charge from the molybdenum penetrates through the thin layer of magnesium oxide and accumulates at the region where the gold cluster is anchored to the magnesium oxide. With a negative charge underneath the gold nanocluster, its attraction to the molybdenum substrate, located under the magnesia film, causes the cluster to collapse. The research appeared in the journal Physical Review Letters.

Aug. 31, 2006 – U.S. scientists using an off-the-shelf inkjet printer have developed a technique for printing patterns of carbon nanotubes on paper and plastic surfaces.

The research team says the method could lead to a new process for manufacturing a wide range of nanotube-based devices, from flexible electronics and conducting fabrics to sensors for detecting chemical agents.

Carbon nanotubes offer the combination of high strength, low weight and excellent conductivity. But most current techniques to make nanotube-based devices require complex and expensive equipment.

“Our results suggest new alternatives for fabricating nanotube patterns by simply printing the dissolved particles on paper or plastic surfaces,” said Robert Vajtai, a researcher with the Rensselaer Nanotechnology Center at Rensselaer Polytechnic Institute and corresponding author of the paper.

Vajtai and colleagues at Rensselaer — along with a group of researchers led by Krisztian Kordas and Geza Toth at the University of Oulu in Finland — explain the discovery in the August issue of the journal Small.

© 2006, YellowBrix, Inc.

August 30, 2006 – SiGe Semiconductor, a provider of ICs and chipscale modules, has raised $19.5 million in an expansion round of funding, to fund new product development and support expanding operations for an expanding global customer base.

“This funding will be instrumental in bringing new products to market, and expanding our portfolio to address high-growth opportunities in the cellular, GPS and WiMAX(TM) markets,” stated Jim Derbyshire, SiGe Semiconductor CEO and chairman. Investments were led by TD Capital, Prism Venture Partners, VenGrowth Private Equity Partners, and 3i Technology Partners, with previous investors Hunt Ventures, RWI Group, GrowthWorks, and Vista Ventures.

The company develops ICs and RF frontend modules for Bluetooth-enabled portable devices, GPS, and telematic systems, as well as 802.11a/b/g/n Wi-Fi devices, and WiMAX broadband access equipment. Revenues surged from $11.9 million in 1H05 to $23.0 million in 2H06, compared with $3.6 million in all of 2003.

August 30, 2006 – Semiconductor manufacturers are increasingly trying to cut expenses and spending, and the first casualty appears to be metrology equipment investments, according to a new report from The Information Network.

Semiconductor yields have reached a point where chipmakers are relaxing wafer sampling and are looking for ways to cut capital expenditures, stated Robert Castellano, president of the New Tripoli, PA-based market research firm. Metrology tool throughput now typically exceeds 130 wafers/hour, meaning faster measurements and less need for metrology capacity, saving both capital expenses and cleanroom space, he said. “Simply put, the performance of the current crop of metrology/inspection systems has gotten too good.” Chipmakers are also deferring purchases of integrated metrology tools in favor of standalone equipment for thin-film measurements, allowing them to sample only some sites on some wafers, he added.

Castellano projects the process control sector will grow about 9.6% in 2006, compared with 15.8% for the overall equipment industry. The macrodefect inspection surged 63% in 2005 vs. just 1.5% for the overall inspection/metrology market, and a 9.5% decrease in overall frontend equipment. But that segment, led by August Technology with 44% share (including Rudolph Technologies), represents just 3.3% of the overall metrology/inspection market, and Castellano says it is now “overcrowded.”

August 24, 2006 – Evans Analytical Group LLC, Sunnyvale, CA, a provider of microanalytical surface analysis and materials characterization services, has acquired the operations and assets of Applied Microanalysis Labs Inc. (AML), an independent lab specializing in static and dynamic secondary ion mass spectrometry (SIMS) techniques, for an undisclosed amount.

AML’s founder Yumin Gao is a recognized expert in characterization of III-V compound semiconductor materials, particularly GaN-based LED structures, the company noted. The acquisition enables Evans “to continue offering improved technical capability and insights to customers in support of both production control and materials development activities,” stated Mike Edgell, EVP of operations. “SIMS continues to be a powerful technique for providing high sensitivity quantitative analysis of silicon and compound semiconductor materials.”

Evans offers microanalytical surface analysis and materials characterization services for identifying the overall atomic and physical structure of materials, including chemical composition and chemical bonding, as well as the level and type of trace impurities. It counts customers in markets ranging from semiconductors and semiconductor equipment to electronics, medical, and biotech, with facilities in the US and Taiwan.

August 23, 2006 – The surge in demand for consumer electronics has led to tracking broader economic trends such as consumer spending as a factor in semiconductor industry growth projections, but adopting one of the major economic benchmarks — US gross domestic product (GDP) — as a leading indicator for the IC industry is not the way to go, according to analyst firm Advanced Forecasting.

“Continuing to use the GDP as a predictive tool for the semiconductor industry today may greatly mislead decision-makers,” according to Rosa Luis, director of marketing and sales for the Saratoga, CA-based firm, noting that the GDP’s historical year-on-year quarterly growth rate lined up well with IC revenues from the period of 2000-2004, but the two metrics were not closely associated in the decade before that, and have not been linked since 2005 to the present.

The firm points out that the 2001 “dot-com” recession was an “anomaly” that hit many US industries particularly hard, not just the IC industry. Metal fabrication, construction materials, and automobiles all experienced increasing growth rates leading to a peak in 2000, followed by a severe decline. Comparing those industries to the US GDP resulted in similarities to with the IC industry’s comparisons for 2000-2004, and with correlations varying from “non-existent to strong” in the other periods.

“The fact that IC revenues matched GDP (with a lag of three months) wasn’t unique to the semiconductor industry, and like in other industries, this phenomenon vanished afterward,” noted the firm, in a statement. “Therefore, continued use of the GDP as a predictive tool for the IC industry based on the strong correlation during that period is risky.”