The Kynix Blog - Memory

Carbon-based memory materials promise to revolutionise how data is stored and to take computing to a new age in terms of speed, efficiency and power. Improved data storage represents the backbone of the knowledge economy, as well as modern industry, business and multimedia. Creating non-volatile data storage can be accomplished through new carbon-based memory materials, which was the aim of the Carbon resistive random access memory materials project.The project team investigated how to develop eco-friendly, cost-effective and energy-efficient memory materials that are scalable to the molecular level and boast a sub-nanosecond switching time with advanced functionality overall.To achieve its aims the team worked on two areas. On one hand it investigated amorphous-carbon based materials and devices in order to supplement current memory technologies such as hard disks and flash memory.On the other it considered graphene-oxide memories for possible use in flexible electronics applications. Storage capabilities in both concepts involved electrical resistive switching, which led to more in-depth research on the topic and establishment of the technology’s limitations, including minimum device size, temperature range and switching speed.The work involved experiments to pinpoint predicted lifetime at different temperatures, multi-level storage capability, suitability within specific applications, and several other pivotal parameters required to develop the technology. After intensive laboratory work, the team successfully built and characterised prototype devices that achieved almost all of the desired objectives.CARERAMM built nanometre amorphous-carbon based devices with sub-petajoule switching energy and oversaw their successful operation at temperatures reaching 300 degrees C. The project built graphene oxide-based devices with 4-level storage and endurance on flexible substrates, as well as GO-based devices that can resist more than 10,000 bending cycles and high bending radii.Overall the team has produced valuable knowledge on the cutting-edge of resistive switching concerning both amorphous carbon and graphene oxide based materials and devices. It combined atomistic scale modelling with nanoscale characterisation to improve switching considerably, paving the way for the commercialisation of advanced carbon-based memory in the near future.Reference:SDUS5EB-001GCXA1512M MT9VDDT6472HY-335 F2 

While investigating mass transit accidents, National Transportation Safety Board (NTSB) officials often rely on digital clues left behind in flash memories of any and all electronic devices—both personal and professional—at a crash site. With the physical forces and high-temperature fires associated with many crashes, memory units are often damaged and sometimes unreadable.Researchers at Binghamton University, State University of New York have figured out how much damage memory units can sustain before becoming unreadable and new repair techniques to retrieve clues off of damaged units, which might help prevent future tragedies."The biggest surprise was how much punishment these devices can take before ceasing to function," said Steve Cain, who is the project manager and a senior research support specialist in the Integrated Electronics Engineering Center (IEEC) at Binghamton University. "As part of their post-crash investigations, the NTSB collects anything and everything at the scene, including personal electronic devices. If the device was active during or just before the crash, it is possible that the data stored in the memory can provide clues as to the cause of the crash. Most of the time the device is ruined, but sometimes it is intact."The interdisciplinary Binghamton group of Cain, Preeth Sivakumar, Jack Lombardi, and Mark Poliks along with James Cash, Joseph Gregor, and Michael Budinski from the NTSB, presented "Fire Damage and Repair Techniques for Flash Memory Modules: Implication for Post-Crash Investigations" at the Fall 2016 International Symposium of Microelectronics.Scientists found plastic coverings started to break down after three hours of exposure to temperatures of 300 degrees Celsius, or about 572 degrees Fahrenheit or more, but memory chips were still readable.Researchers pointed out that even with the pressures and forces in play during past crashes, temperatures typically only reach those levels for short periods of time."Data integrity was maintained even in a plasma discharge," Cain said. "Basically, if the device doesn't burn up, there is a reasonable chance of the data being retained in the chip. The only problem is that the connections to the memory chips may be broken, so that the data cannot be read."For the second part of the study, researchers addressed the readability issue. The team purposely damaged memory units and then extracted memory chips using acid, lasers, plasma, or mechanical polishing.Lasers were the most effective extraction method and mechanical extractions was the simplest, but each method still damaged the wire bonds within memory chips and made many unreadable. A specialized metallic ink from a precision printer was used to restore functionality."These results expand the investigative scope for aviation accidents, where the data rather than the device is of paramount importance," the team concluded. "It is possible to repair the interconnections of flash memory modules, provided the chip is intact." Reference:MT16JTF51264AZ-1G6M1SDUS5EB-001GMD2202-D192 

Scientists often discover interesting things without completely understanding how they work. That has been the case with an experimental memory technology in which temperature and voltage work together to create the conditions for data storage. But precisely how was unknown. But when a Stanford team found a way to untangle the chip’s energy and heat requirements, their tentative findings revealed a pleasant surprise: The process may be more energy efficient than was previously supposed.That’s good news for next-generation mobile devices whose batteries would last longer if they were powering lower energy chips. The group that made this discovery, led by Stanford electrical engineer H.-S. Philip Wong, is presenting the paper when the IEEE International Electron Devices Meeting (IEDM) brings leading researchers to San Francisco Dec. 5.The new technology the team investigated is called resistive random-access memory, or RRAM for short. RRAM is based on a new type of semiconductor material that forms digital zeros and ones by resisting or permitting the flow of electrons.RRAM has the potential to do things that aren’t possible with silicon: for instance, being layered on top of computer transistors in new three-dimensional, high-rise chips that would be faster and more energy efficient than current electronics, which is ideal for smartphones and other mobile devices where energy efficiency is a vital feature.But while engineers can observe that RRAM does store data, they don’t know exactly how these new materials work. “We need much more precise information about the fundamental behavior of RRAM before we can hope to produce reliable devices,” Wong said. So to help engineers understand some of the unknowns, Wong’s team built a tool to measure the basic forces that make RRAM chips work.Graduate student Zizhen Jiang of the Stanford team explained the basics: RRAM materials are insulators, which normally do not allow electricity to flow, she said. But under certain circumstances, insulators can be induced to let electrons flow.Past research had shown how: Jolting RRAM materials with an electric field causes a pathway to form that permitted electron flows. This pathway is called a filament. To break the filament, researchers apply another jolt and the material becomes an insulator again. So each jolt switched the RRAM from zero to one or back, which is what makes the material useful for data storage.But electricity is not the only force at play in RRAM switching. Pumping electrons into any material raises its temperature. That’s the principle behind electric stoves. In the case of RRAM, it was the elevated temperature caused by introducing voltage that induced filaments to form or break. The question was what voltage-induced temperature was needed to cause the switching. No one knew.Before the new Stanford study researchers thought short bursts of voltage, sufficient to generate temperatures of about 1,160ºF – hot enough to melt aluminum – was the switching point. But those were estimates because there was no way to measure the heat generated by an electric jolt. “In order to begin to answer our questions, we had to decouple the effects of voltage and temperature on filament formation,” said Ziwen Wang, another graduate student on the team.Essentially, the Stanford researchers had to heat the RRAM material without using an electric field. So they put an RRAM chip on a micro thermal stage (MTS) device – a sophisticated hot plate capable of generating a wide range of temperatures inside the material.Of course the objective was not merely to heat the material, but also to measure how filaments formed. Here they took advantage of the fact that RRAM materials are insulators in their natural state. That makes them digital zeros. As soon as a filament formed electrons would flow. The digital zero would become a digital one, which the researchers could detect.Using this experimental model, the team put RRAM chips on the burner and cranked up the heat, starting at about 80ºF – roughly the temperature of a warm room – all the way up to 1,520ºF, hot enough to melt a silver coin. Heating the RRAM to various temperatures in between these extremes, the researchers measured precisely if and how RRAM switched from its native zero to a digital one.To their pleasant surprise, the researchers observed that filaments could form more efficiently at ambient temperatures between 80ºF and 260ºF, which is hotter than boiling water – contrary to prior expectation that hotter was better.If confirmed by subsequent research, this would be good news because in a working chip the switching temperature would be created by the voltage and duration of the electric jolt. Efficient switching at lower temperatures would require less electricity and make RRAM more energy efficient and extend battery life when used as the memory in mobile devices.Much work remains to be done to make RRAM memory practical but this research provides the test bed to vary conditions systematically instead of relying on hit-and-miss hunches. “Now we can use voltage and temperature as design inputs in a predictive manner and that is going to enable us to design a better memory device,” Wang said.Reference:MT16JTF51264AZ-1G6M1SDUS5EB-001GMD2202-D192  

How can quantum information be stored as long as possible? An important step forward in the development of quantum memories has been achieved by a research team of TU Wien.Conventional memories used in today's computers only differentiate between the bit values 0 and 1. In quantum physics, however, arbitrary superpositions of these two states are possible. Most of the ideas for new quantum technology devices rely on this "Superposition Principle". One of the main challenges in using such states is that they are usually short-lived. Only for a short period of time can information be read out of quantum memories reliably, after that it is irrecoverable.A research team at TU Wien has now taken an important step forward in the development of new quantum storage concepts. In cooperation with the Japanese telecommunication giant NTT, the Viennese researchers lead by Johannes Majer are working on quantum memories based on nitrogen atoms and microwaves. The nitrogen atoms have slightly different properties, which quickly leads to the loss of the quantum state. By specifically changing a small portion of the atoms, one can bring the remaining atoms into a new quantum state, with a lifetime enhancement of more than a factor of ten. These results have now been published in the journal Nature Photonics.Nitrogen in diamond"We use synthetic diamonds in which individual nitrogen atoms are implanted", explains project leader Johannes Majer from the Institute of Atomic and Subatomic Physics of TU Wien. "The quantum state of these nitrogen atoms is coupled with microwaves, resulting in a quantum system in which we store and read information."However, the storage time in these systems is limited due to the inhomogeneous broadening of the microwave transition in the nitrogen atoms of the diamond crystal. After about half a microsecond, the quantum state can no longer be reliably read out, the actual signal is lost. Johannes Majer and his team used a concept known as "spectral hole burning", allowing data to be stored in the optical range of inhomogeneously broadened media, and adapted it for supra-conducting quantum circuitsand spin quantum memories.Dmitry Krimer, Benedikt Hartl and Stefan Rotter (Institute of Theoretical Physics, TU Wien) have shown in their theoretical work that such states, which are largely decoupled from the disturbing noise, also exist in these systems. "The trick is to manoeuver the quantum system into these durable states through specific manipulation, with the aim to store information there," explains Dmitry Krimer.Excluding specific energies"The transitions areas in the nitrogen atoms have slightly different energy levels because of the local properties of the not quite perfect diamond crystal", explains Stefan Putz, the first author of the study, who has since moved from TU Wien to Princeton University. "If you use microwaves to selectively change a few nitrogen atoms that have very specific energies, you can create a "Spectral Hole". The remaining nitrogen atoms can then be brought into a new quantum state, a so-called "dark state", in the center of these holes. This state is much more stable and opens up completely new possibilities.""Our work is a 'proof of principle' – we present a new concept, show that it works, and we want to lay the foundations for further exploration of innovative operational protocols of quantum data," says Stefan Putz.With this new method, the lifetime of quantum states of the coupled system of microwaves and nitrogen atoms increased by more than one order of magnitude to about five microseconds. This is still not a great deal in the standard of everyday life, but in this case it is sufficient for important quantum-technological applications. "The advantage of our system is that one can write and read quantum information within nanoseconds," explains Johannes Majer. "A large number of working steps are therefore possible in microseconds, in which the system remains stable."Reference: S29GL032N11FFIS42S29GL064N90FFIS30S29AS016J70BFA040  

A low-cost, low-risk memory solution has been announced by Microchip, it offers unlimited endurance and safe data storage at power loss. This I2C EERAM memory is an easy to implement, Non-Volatile SRAM (NVSRAM) that can be used by applications that need to constantly or instantaneously record, update or monitor data in sectors which include metering, automotive and industrial.EERAM is a standalone SRAM with shadow EEPROM back-up on a single chip that helps to automatically retain the contents of the SRAM memory when system power is lost. The EERAM offers instant random writes to the array with no write-cycle delay. The I2C EERAM family is available in 4 and 16Kb densities and in standard 8-pin SOIC, TSSOP and PDIP packages. EERAM is available in 3.0 and 5.0V options and in industrial and automotive temperature ranges, of -40 to 85°C and -40 to 125°C respectively and is also available as an automotive-grade memory.Comprised of two familiar and reliable memory technologies on a single chip, EEPROM and SRAM, EERAM offers a robust and dependable data solution that is also the lowest cost non-volatile SRAM solution. EERAM does not require an external battery to safely store data during a power-loss event. Instead, a small, external capacitor is used to provide the energy needed to store the contents of the SRAM on to the EEPROM when system power is lost.Key features:I2C EERAM is a low-cost NVSRAM that requires no external battery to retain dataCombines SRAM with EEPROM back-up on a single chip for lowest-cost NVSRAM solutionEnables instant random writes to the array with no write-cycle delayBenefits applications which constantly or instantaneously record, update or monitor dataAvailable in industrial and automotive temperature rangesReference:KY32-BQ2201SN-NKY32-DP8421AV-20KY32-DS1321KY32-MXD1210CSA+ 

Samsung Electronics unveiled the industry’s first removable memory cards based on the JEDEC UFS 1.0 Card Extension Standard, for use in high-resolution mobile shooting devices such as DSLRs, 3D VR cameras, action cams and drones. Coming in a wide range of storage capacities including 256, 128, 64 and 32 GB, Samsung’s UFS cards are expected to bring a significant performance boost to the external memory storage market, allowing much more satisfying multimedia experiences.“Our new 256GB UFS card will provide an ideal user experience for digitally-minded consumers and lead the industry in establishing the most competitive memory card solution,” said Jung-bae Lee, senior vice president, Memory Product Planning & Application Engineering, Samsung Electronics.“By launching our new high-capacity, high-performance UFS card line-up, we are changing the growth paradigm of the memory card market to prioritise performance and user convenience above all.”Samsung’s new 256GB UFS removable memory card ─ simply referred to as the UFS card will provide greatly improved user experiences, especially in high-resolution 3D gaming and high-resolution movie playback.It provides more than five times faster sequential read performance compared to that of a typical microSD card, reading sequentially at 530 MB/s which is similar to the sequential read speed of the most widely used SATA SSDs.With this UFS card, consumers have the ability to read a 5GB, Full-HD movie in approximately 10 seconds, compared to a typical UHS-1 microSD card, which would take over 50 seconds with 95MB/s of sequential reading speed.Also, at a random read rate of 40,000 IOPS, the 256GB card delivers more than 20 times higher random read performance compared to a typical microSD, which offers approximately 1,800 IOPS.When it comes to writing, the new 256GB UFS card processes 35,000 random IOPS, which is 350 times higher than the 100 IOPs of a typical microSD card, and attains a 170MB/s sequential write speed, almost doubling the top-end microSD card speed.With these substantial performance improvements, the new 256GB UFS card significantly reduces multimedia data downloading time, photo thumbnail loading time and buffer clearing time in burst shooting mode, which, collectively, can be particularly beneficial to DSLR camera users.To shoot 24 large/extra fine JPEG photographs (1,120 MB-equivalent) continuously with a high-end DSLR camera, the 256GB UFS card takes less than seven seconds, compared to a UHS-1 microSD card which typically takes about 32 seconds, at 35MB/s.To achieve the highest performance and most power-efficient data transport, the UFS card supports multiple commands with command queuing features and enables simultaneous reading and writing through the use of separately dedicated paths, doubling throughput.As the leading memory storage provider, Samsung has been aggressive in preparing UFS solutions for the marketplace, while contributing to JEDEC standardisation of the Universal Flash Storage 2.0 specification in September 2013 and the UFS 1.0 Card Extension standard in March 2016.Following its introduction of the industry-first 128GB embedded UFS chip in January 2015, the company successfully launched a 256GB embedded UFS memory for high-end mobile devices in February of this year.As of earlier this month, Samsung also completed the Universal Flash Storage Association (UFSA)’s certification program that evaluates electrical and functional specifications for compatibility of a UFS card, and Samsung’s new UFS card products were approved as UFSA-certified UFS cards with the right to use the official UFS logo for the first time in the industry.Reference:S29GL032N11FFIS42S29GL064N90FFIS30S29AS016J70BFA040