The Kynix Blog

 Samsung's recall of 2.5 million Galaxy Note 7 phones after several dozen caught fire and exploded may stem from a subtle manufacturing error, but it highlights the challenge electronics makers face in packing ever more battery power into ever thinner phones, while rushing for faster release dates.Announcing the recall on Sept. 2, Samsung confirmed dozens of cases where Note 7 batteries caught fire or exploded, mostly while charging. It plans a software update that will cap battery recharging at 60 percent capacity to help minimize risks of overheating. But it is urging owners to keep the phones turned off until they can get them replaced, beginning Monday.U.S. safety regulators stepped in Thursday with an official recall, saying Samsung's voluntary efforts were inadequate. Though Samsung promised replacement devices, the U.S. Consumer Product Safety Commission said U.S. customers would be eligible for refunds if they choose. Replacements are expected in stores by next Wednesday.The Note 7 debuted to rave reviews in August thanks to its speed, new software features and—not least—the estimated nine hours it would run between charges. But all that power comes at a price: Users began reporting the phones were catching fire or exploding, in one case incinerating the SUV it had been left in.Aviation authorities in the U.S., Australia and Europe have urged passengers not to use or charge Note 7s while flying and not to put them in checked baggage. On Monday, Canada issued an official recall.Koh Dong-jin, Samsung's mobile president, said in announcing the recall on Sept. 2 that an investigation turned up a "tiny error" in the manufacturing process for the faulty batteries in the Note 7s that was very difficult to identify. The end of the pouch-shaped battery cell had some flaws that increased the chance of stress or overheating, he explained.That kind of manufacturing error is unimaginable for top-notch battery makers with adequate quality controls, said Park Chul Wan, a former director of the next generation battery research center at the state-owned Korea Electronics Technology Institute.Samsung and other experts should search for factors outside the battery cells that could have led to overheating, he said."If Koh's argument is right, that makes Samsung SDI a third-rate company," Park said. "But it does not appear to be a simple battery problem."Time also is a factor in marketing and making the phones.In 2015, Samsung moved up its unveiling of its new Galaxy Note model to August from September, seeking a leg up on Apple's September iPhone upgrades.Before the issue of battery explosions emerged, supplies were not keeping pace with demand for the Note 7.Samsung has not recalled Note 7s sold in China, but the company has refused to say which of its two battery suppliers made the faulty batteries or clarify whose batteries are used in which Note 7 smartphones. The company also refused comment on South Korean media reports that it has stopped using batteries from Samsung SDI, one of its two suppliers, in the Note 7.C.W. Chung, an analyst at Nomura Securities in Seoul, cited SDI officials in estimating that about 70 percent of the batteries for the Galaxy Note 7 smartphones came from SDI.The other 30 percent are thought to have been supplied by Amperex Technology Ltd., a Chinese-based manufacturer that reportedly also is a main supplier of batteries for the iPhone.Problems with lithium batteries have afflicted everything from laptops to Tesla cars to Boeing's 787 jetliner, though having so many lithium-ion battery fires in a short time is unheard of, Park said.The batteries are ubiquitous in consumer electronic devices, favored by manufacturers because they are lightweight and pack much more energy into a small space than other power cells.But storing so much energy in a tiny space, with combustible components separated by ultra-thin walls, makes them susceptible to overheating if exposed to high temperatures, damage or flaws in manufacturing. If the separators fail, a chemical reaction can quickly escalate out of control.That's what happened with the Note 7, Samsung's Koh explained."The flaw in the manufacturing process resulted in the negative electrodes and the positive electrodes coming together," he told reporters in Seoul.It is unclear how Samsung failed to discover the battery problem before launching the Note 7. It confirmed delays in shipments for extra quality tests weeks later, in late August, after photos of charred phones began popping up on social media.South Korean experts suggested Samsung may have been so ambitious with the Note 7's design that it compromised safety."There was no choice but to make the separator (between positive and negative anodes) thin because of the battery capacity," said Lee Sang-yong, a professor at Ulsan National Institute of Science and Technology who worked more than a decade at LG Chem, a leading lithium battery maker. Thicker separators can improve safety but will not necessarily prevent all overheating issues, he said.Doh Chil-Hoon, head of the state-run Korea Electrotechnology Research Institute's battery research division, said that based on the limited information provided by Samsung, he believes the push to increase battery power was part of the problem."Even with a small manufacturing mistake, if there had been enough elements to ensure safety, it would not explode," Doh said. "It is a roundabout way of admitting weak safety."The Note 7 phones have a powerful 3,500 milliampere hour battery, whereas the Galaxy S7 smartphone, which has a slightly smaller body than the Note 7, features a 3,000 mAh battery. So does the Note 5, launched in 2015.Apple does not provide information on the iPhone's battery capacity in milliampere hours. But two research firms that specialize in analyzing tech gadgets and their components said the battery in the iPhone 6S Plus is 2,750mAh. The size of the battery in the newly released iPhone 7 is not yet known.The 3,500 mAh battery in the Samsung Note 7 is "one of the highest, if not the highest, capacity battery we've seen in a phone," said Wayne Lam, an industry analyst at IHS Markit Technology.Lam said he thinks the Note 7 battery problem resulted from weak controls in manufacturing, not a poor or unsafe design.A spokeswoman at iFixit, which publishes repair guides for electronic gadgets, offered a similar view. "We don't think any internal design changes in the Note 7 are responsible for the exploding batteries—more likely just a manufacturing defect," IFixit's Kay-Kay Clapp said in an email.Apple has tweaked hardware and software it developed itself to make iPhones use power more efficiently, while Samsung has increased the capacity of the batteries in its phones.That can be done without increasing size by adjusting components or changing the production process, Lam said."You have two different trajectories, with Samsung packing in more energy density, versus Apple trying to trim it down by optimizing everything else," he said, adding that the two rivals are "constantly locked in this arms race of improving and one-upping."While Apple and Samsung are using built-in batteries for their premium phones, LG Electronics, Samsung's smaller South Korean rival, has opted for a replaceable, 3,200 mAh capacity battery for its new premium, jumbo screen smartphone, the V20.LG chose to make the phone thinner and allow customers to extend battery life by swapping out batteries."The security of the battery isn't directly related to whether the battery is replaceable or not," Cho Joon-ho, head of LG's mobile business, told reporters. "But we make efforts to secure safety with quality controlling tests beforehand."  

Toshiba Corporation today announced that it has developed the world's first 15-nanometer (nm) process technology, which will apply to 2-bit-per-cell 128-gigabit (16 gigabytes) NAND flash memories. Mass production with the new technology will start at the end of April at Fab 5 Yokkaichi Operations, Toshiba's NAND flash fabrication facility (fab), replacing second generation 19 nm process technology, Toshiba's previous flagship process. The second stage of Fab 5 is currently under construction, and the new technology will also be deployed there.Toshiba has achieved the world's smallest class chip size with the 15nm process plus improved peripheral circuitry technology. The new chips achieve the same write speed as chips formed with second generation 19 nm process technology, but boost the data transfer rate to 533 megabits a second, 1.3 times faster, by employing a high speed interface.Toshiba is now applying the 15nm process technology 3-bit-per-cell chips, and aims to start mass production in the first quarter of this fiscal year, to June 2014. The company will develop controllers for embedded NAND flash memory in parallel and introduce 3-bit-per-cell products for smartphones and tablets, and will subsequently extend application to notebook PCs by developing a controller compliant with solid state drives (SSD). 

Researchers from the University of Twente MESA+ research institute, together with the company SolMateS, have developed a new type of transistor to reduce the power consumption of microchips. The basic element of modern electronics, namely the transistor, suffers from significant current leakage. By enveloping a transistor with a shell of piezoelectric material, which distorts when voltage is applied, researchers were able to reduce this leakage by a factor of five (compared to a transistor without this material). An article presenting the prototype of the transistor appears in the June issue of IEEE Transactions on Electron Devices, an authoritative scientific journal in the field of transistor research.Current leakage in transistors is one of the causes of battery depletion in portable electronic devices, such as smartphones and laptops. With the new type of transistor, either the current leakage (while the transistor is not active) or the energy consumption (while the transistor is active) can be addressed. In the latter case, it is estimated that energy consumption can be reduced by approximately 10%.Intelligent squeezingThe trick lies in a piezoelectric material which is applied to the exterior of the transistor. The piezoelectric material expands when you apply a voltage to it and compresses the silicon in the transistor with a pressure of about 10,000 atmospheres. This high pressure ensures that electrons flow through the transistor faster. You can therefore make microchips more efficient by 'intelligently squeezing the transistor'.Incidentally, existing transistors are already put under high pressure in order to improve their efficiency. In this case, however, the pressure is permanently built in, which actually increases the current leakage. In the prototype designed by the UT, the transistor is only put under pressure when required and this makes a big difference. The electric current needed to switch the transistor from on to off is thereby partly replaced by mechanical tension.CrudeAccording to dr. ir. Ray Hueting from the chair Semiconductor Components, this is an initial prototype that can already produce energy savings. "The design is still fairly crude where the material is concerned. With the further development of the transistor, it should therefore be possible to achieve a further significant increase in efficiency."The operating principle of this transistor was theoretically predicted in 2013 by the same research group. But in advance it was by no means certain that the transistor would be a success. The reason for this is that piezoelectric materials and silicon (which transistors are made of) are difficult to combine. The researchers solved this by inserting a buffer layer between the two materials.    

Fujitsu Semiconductor Europe today announced a new arrival to its FerVID family of chips for RFID tags. As with all members of the FerVID family, the MB89R112 series uses ferroelectric memory (FRAM) for fast write speeds, high-frequency rewritability, radiation tolerance and low-power operation. With industry-leading 9 KB memory, the series offers tailored solutions for factory automation and medical equipment as well as for embedded and industrial applications.  Since 2004, Fujitsu has developed FRAM products as part of the FerVID family with two frequency bands, for use as chips in high-functionality RFID tags operating in the HF band (13.56 MHz) and UHF band (860 to 960 MHz). Today, its products serve a wide range of applications, including chips for data-carrier tags in the factory automation and maintenance sectors, chips capable of withstanding gamma radiation or electron beams for the medical and pharmaceutical sectors, and chips with serial interfaces for embedded applications.The new MB89R112 series includes 9 KB of FRAM, the greatest density available in an RFID chip operating in the HF band as defined in ISO/IEC 15693. Of this 9 KB, 8 KB is provided as user memory, enabling access by read/write operations to the entire 8 KB region as defined in ISO/IEC 15693. The series will be offered in two variants, with 24pF and 96pF input capacitance. Writing 8 KB of data takes approximately four seconds, a high-speed operation that is six times faster than speeds achieved by E2PROM products. The greater data volume available on RFID tags enables greater efficiency for applications such as product lifecycle traceability management – from manufacturing to logistics, use and disposal – or on-site data logging for equipment maintenance records.The market is demanding higher-capacity memory, plus RFID connectivity to sensors and microcontrollers, so as to facilitate the wireless modification of product operating parameters or the logging of environmental factors during distribution. These features would benefit production control in automotive and electronics manufacturing, as well as maintenance applications in aviation, road-building, construction and civil engineering.The MB89R112QN products enable these features by supplementing the HF RFID interface with an additional SPI serial interface for microcontroller connectivity. Since the 8 KB of user memory in FRAM can be accessed from the microcontroller via SPI, shared memory regions can be used both for data logging and as a parametric area for changing the microcontroller's operating parameters.Application examples include logging environmental readings for logistics, detecting equipment errors, modifying electronic displays, altering sensor threshold values, changing firmware settings, plus many other novel and innovative applications that were previously unworkable. 

A new type of transistor that could make possible fast and low-power computing devices for energy-constrained applications such as smart sensor networks, implantable medical electronics and ultra-mobile computing is feasible, according to Penn State researchers. Called a near broken-gap tunnel field effect transistor (TFET), the new device uses the quantum mechanical tunneling of electrons through an ultrathin energy barrier to provide high current at low voltage.Penn State, the National Institute of Standards and Technology and IQE, a specialty wafer manufacturer, jointly presented their findings at the International Electron Devices Meeting in Washington, D.C. The IEDM meeting includes representatives from all of the major chip companies and is the recognized forum for reporting breakthroughs in semiconductor and electronic technologies.Tunnel field effect transistors are considered to be a potential replacement for current CMOS transistors, as device makers search for a way to continue shrinking the size of transistors and packing more transistors into a given area. The main challenge facing current chip technology is that as size decreases, the power required to operate transistors does not decrease in step. The results can be seen in batteries that drain faster and increasing heat dissipation that can damage delicate electronic circuits. Various new types of transistor architecture using materials other than the standard silicon are being studied to overcome the power consumption challenge."This transistor has previously been developed in our lab to replace MOSFET transistors for logic applications and to address power issues," said lead author and Penn State graduate student Bijesh Rajamohanan. "In this work we went a step beyond and showed the capability of operating at high frequency, which is handy for applications where power concerns are critical, such as processing and transmitting information from devices implanted inside the human body." For implanted devices, generating too much power and heat can damage the tissue that is being monitored, while draining the battery requires frequent replacement surgery. The researchers, led by Suman Datta, professor of electrical engineering, tuned the material composition of the indium gallium arsenide/gallium arsenide antimony so that the energy barrier was close to zero—or near broken gap, which allowed electrons to tunnel through the barrier when desired. To improve amplification, the researchers moved all the contacts to the same plane at the top surface of the vertical transistor.This device was developed as part of a larger program sponsored by the National Science Foundation through the Nanosystems Engineering Research Center for Advanced Self-Powered Systems of Integrated Sensors and Technologies (NERC-ASSIST). The broader goal of the ASSIST program is to develop battery-free, body-powered wearable health monitoring systems with Penn State, North Carolina State University, University of Virginia, and Florida International University as participating institutions.   

Researchers at Chalmers University of Technology, Sweden, have demonstrated an integrated amplifier with the lowest noise performance so far. The amplifier offers new possibilities for detecting the faintest electromagnetic radiation, for example from distant galaxies.Last year, Chalmers reported a world record for a low-noise amplifier in the prestigious journal Electron Device Letters. The amplifier exhibited a minimum noise figure of 0.018 dB across a bandwidth of 4-8 GHz. However, since the low-noise amplifier was designed in a hybrid solution, scaling up to larger quantities turned out to be very difficult.Chalmers has now in collaboration with a company called Low-Noise Factory published an article on an integrated ultra-low-noise amplifier. The scientists have developed a unique indium phosphide-based process for what is known as high electron mobility transistors (HEMT). Transistors and other semiconductor components have been fabricated on a monolithic chip on an indium phosphide wafer. All parts of the design such as semiconductor layers, components, process and circuit design have been optimised for the lowest noise performance.As a result, an integrated 2.0 x 0.75 mm amplifier with an ultra-low-noise figure of 0.045 dB was demonstrated. The amplifier had a very large bandwidth of 0.5-13 GHz and a high gain exceeding 38 dB across the frequency band. In order to show such extreme performance, the amplifier was cooled to minus 260 degrees of Celsius."The combination of high gain, large bandwidth and ultra-low-noise figure makes this circuit very attractive for large multipixel arrays containing thousands of antennas," says Jan Grahn, research group leader at Chalmers."The integrated ultra-low-noise process enables the fabrication of thousands of amplifiers with identical performance. One potential future application is in the world's largest radio telescope SKA (Square Kilometer Array) that is being planned, an international project where the Onsala Space Observatory at Chalmers is one of the acting members. In huge applications such as the SKA, even a small noise-figure reduction in the first low-noise amplifier in the receiver chain may potentially bring about major savings in the final system design."