Emerging Memory Technologies: Design, Architecture, and Applications


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First, the speaker will provide an overview of architectural modeling techniques for emerging memory technologies. Next, the speaker will describe novel architectural techniques that exploit these new memory technologies in computer memory hierarchies. Finally, novel applications that leverage the unique benefits of these emerging memory technologies will be presented. Bio: Yuan Xie received the B. He has published more than research papers in journals and refereed conference proceedings, in the area of EDA, computer architecture, VLSI circuit designs, and embedded systems.

About Us. Brief Introduction. Address from the Director.

Computer Architecture - Lecture 7: Emerging Memory Technologies (ETH Zürich, Fall 2017)

Contact the director. Schematic plots of a Flash memory cell and the degradation of its tunnel oxide. The degradation leads to the formation of percolation paths responsible for the FG charge loss, hence the loss of the stored information. The presence of traps in the energy barrier yields the trap-assisted tunneling mechanism and originates the stress-induced leakage current SILC. The FGNV memory is a basic building block of Flash memory, which is based on FG thin-film storage TFS memories that have been developed with the addition of an erase gate configuration.

This what makes Flash memory nonvolatile and all floating gate memories to have the same generic cell structure. Because the floating gate is electrically isolated by the oxide layer, any electrons placed on it are trapped there. Flash memory works by adding charging or removing discharging electrons to and from a floating gate.

A bit's 0 or 1 state depends upon whether or not the floating gate is charged or discharged. This is the normal state for a floating gate. The charge, holes or electrons, are injected into the nitride layer using direct tunneling through the tunnel oxide layer. The nitride layer is electrically isolated from the surrounding transistor, although charges stored on the nitride directly affect the conductivity of the underlying transistor channel.

Since the SONOS memory possesses spatially isolated deep-level traps, a single defect in the tunneling oxide will not cause discharge of the memory cell. The thickness of the top oxide is important to prevent the Fowler-Nordheim tunneling of electrons from the gate during erase.

When the polysilicon control gate is biased positively, electrons from the transistor source and drain regions tunnel through the oxide layer and get trapped in the silicon nitride. This results in an energy barrier between the drain and the source, raising the threshold voltage V th the gate-source voltage necessary for current to flow through the transistor.

Moreover, the nitride layer is electrically isolated from the surrounding transistor, although charges stored on the nitride directly affect the conductivity of the underlying transistor channel. However, SONOS-type Flash memories have several drawbacks such as shallow trap energy level, erase saturation, and vertical stored charge migration [ 74 ]. The programming speed and operating voltage problems can be solved by reducing the tunnel oxide thickness.

At low tunnel oxide thickness, the issues that impact SONOS-type memories include erase saturation and vertical charge migration, which seriously degrade the retention capability of the memory [ 75 ]. Thus, many concerns still remain for the SONOS type of memories, which will be discussed in the next section. Scaling demands very thin gate insulators in order to keep short channel effects and control the shrinkage of the device size and maximize the performance. Many studies have shown that the charge retention characteristics in scaled SONOS nonvolatile memory devices with a low gate oxide thickness and at high temperature are problematic with shallow-level traps [ 48 , 77 , 78 ].

For the conventional SONOS memory, erase saturation and vertical stored charge migration [ 79 , 80 ] are the two major drawbacks; the most challenging tasks are how to maintain an acceptable charge capability of the discrete storage nodes and how to fabricate nanocrystals with constant size, high density, and uniform distributions [ 81 ]. This erase saturation makes SONOS erase less as the erase voltage or the tunnel oxide thickness is increased. Since the SONOS memory uses silicon nitride as a charge trapping layer, the electrons in the Si sub-conduction band will tunnel through the tunneling oxide and a portion of the nitride, and this consequently degrades the program speed.

Besides this, the conduction band offset of nitride is only 1. Although applying a very high electric field may accelerate the de-trapping rate, the gate electron injection current exceeds the de-trapping but resulting in practically an increase in charge and no erasing. However, the direct tunneling cannot be turned off at a low electric field, leading to poor retention and read disturb.

The main reason for the growth of emerging NVM technologies is that scaling has now become a serious issue for the memory industry. Not only are many of these new technologies inherently more scalable, but also they seem well suited to the next generation of mobile computing and communications that will demand high-capacity memories capable of storing and rapidly accessing video and a large database without overburdening battery power sources.

Practical information

This indicates the reduced memory window as the erase voltage is increased. Many alternate device structures are proposed to hopefully circumvent these scaling challenges and to improve the device performance. At the present time, such an ideal memory has not been developed. These structures will be considered in the next sections. In light of such issues, emerging memory solutions seem to be a key technology. Recent studies have revealed that there is a close correlation among existing and emerging memory technologies in view of scalability.

The scaling trend of memory transition leads to smaller and smaller memory devices, which have been routinely observed. To further support this assertion, another set of current progress in memory technology is described to the increasing importance of memory to users' experience and the importance of memory to system performance. There are many emerging memory technologies which are trying to replace existing memory technologies in the market.

But the ideal characteristics of new emerging memory technologies have to be meeting the performance of SRAM and the density of NAND Flash in terms of stability, scalability, and switching speed. Thus, going beyond the traditional bistable memory, the possibilities of multilevel, high-performance memory devices suitable for market must be explored. Each of these memory technologies will be briefly outlined and discussed in the following sections.

It is necessary for any new technology to be able to deliver most for industry adoption. For industry adoption on a mass scale, some parameters must be matched with existing memory technologies. In consideration of new technology for industry application, the scalability of the technology, speed of the device, power consumption to be better than existing memories, endurance, densities, better than existing technologies and most importantly the cost; if the emerging technology can only run one or two of these attributes, then, at most desirable, it is likely to be resigned to niche applications.

MRAM is basically based on memory cells having two magnetic storage elements, one with a fixed magnetic polarity and another with a switchable polarity. Moreover, scientists define a metal as magnetoresistive if it shows a slight change in electrical resistance when placed in a magnetic field. By combining the high speed of static RAM and the high density of DRAM, proponents say that MRAM could be used to significantly improve electronic products by storing greater amounts of data, enabling it to be accessed faster while consuming less battery power than existing electronic memories.

Technically, it works with the state of the cell, which is sensed by measuring the electrical resistance while passing a current through the cell. However, if the magnetic moments are antiparallel, the cell resistance will be high. The memory characteristics of MRAM of writing and erasing are fulfilled by passing a current through the write line to induce a magnetic field across the cell. MRAM has been slowly getting off the ground but has now entered the market and will become increasingly available for mass production in the couple of years and beyond.

Currently, it has reached some level of commercial success in niche applications [ 87 ]. In view of power consumption and speed, MRAM competes favorably than other existing memories such as DRAM and Flash, with an access time of a few nanoseconds [ 88 - 90 ].

Emerging Memory Technologies - Design, Architecture, and Applications | Yuan Xie | Springer

According to this price level, MRAM is in excess of 1, times the price of Flash memory and over 10, times the price of hard disk drives. STT-MRAM is a magnetic memory technology that exerts the base platform established by an existing memory called MRAM to enable a scalable nonvolatile memory solution for advanced process nodes [ 92 , 93 ]. As we have discussed in the previous section, MRAM stores data according to the magnetization direction of each bit and the nanoscopic magnetic fields set the bits in conventional MRAM.

In addition, STT-RAM writing is a technology in which an electric current is polarized by aligning the spin direction of the electrons flowing through a magnetic tunnel junction MTJ element. Data writing is performed by using the spin-polarized current to change the magnetic orientation of the information storage layer in the MTJ element [ 94 ]. The resultant resistance difference of the MTJ element is used for information readout. However, for STT-RAM to be adopted as a universal mainstream semiconductor memory, some key challenges should be resolved: the simultaneous achievement of low switching current and high thermal stability.

The cell is then accessed via the transistor, which enables the ferroelectric state of the capacitor dielectric to be sensed. In spite of its name, FeRAM does not contain iron. The polarization properties of a ferroelectric substance are used as a memory device. FeRAM is the most common kind of personal computer memory with the ability to retain data when power is turned off as do other nonvolatile memory devices such as ROM and Flash memory [ 97 ].

In a DRAM cell, the data periodically need refreshing due to the discharging of the capacitor, whereas FeRAM maintains the data without any external power supply. It achieves this by using a ferroelectric material in the place of a conventional dielectric material between the plates of the capacitor. When an electric field is applied across dielectric or ferroelectric materials, it will polarize, and while that field is removed, it will depolarize. But the ferroelectric material exhibits hysteresis in a plot of polarization versus electric field, and it will retain its polarization.

One disadvantage of FeRAM is that has a destructive read cycle. The read method involves writing a bit to each cell; if the state of the cell changes, then a small current pulse is detected by indicating that the cell was in the OFF state. However, it is a fast memory that can endure a high number of cycles e.

It is expected to have many applications in small consumer devices such as personal digital assistants PDAs , handheld phones, power meters, and smart cards, and in security systems. FeRAM is faster than Flash memory. Even after FeRAM has achieved a level of commercial success, with the first devices released in [ 99 , ], current FeRAM chips offer performance that is either comparable to or exceeding current Flash memories [ 98 , ], but still slower than DRAM.

Basic structure of a FeRAM cell. The crystal structure of a ferroelectric and an electric polarization-electric field hysteresis curve are also shown. Most phase-change materials contain at least one element from group 6 of the periodic table, and the choice of available materials can be further widened by doping these materials [ - ].

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These materials are in fact commonly used as the data layer in rewritable compact disks and digital versatile disks CD-RW and DVD-RW where the change in optical properties is exploited to store data. The structure of the material can change rapidly back and forth between amorphous and crystalline on a microscopic scale. The material has low electrical resistance in the crystalline or ordered phase and high electrical resistance in the amorphous or disordered phase.

This allows electrical currents to be switched ON and OFF , representing digital high and low states. This process has been demonstrated to be on the order of a few tens of nanoseconds [ ], which potentially makes it compatible with Flash for the read operation, but several orders of magnitude faster for the write cycle.

This makes it possible for PCM to function many times faster than conventional Flash memory while using less power. In addition, PCM technology has the potential to provide inexpensive, high-speed, high-density, high-volume nonvolatile storage on an unprecedented scale. The physical structure is three-dimensional, maximizing the number of transistors that can exist in a chip of fixed size.

PCM is sometimes called perfect RAM because data can be overwritten without having to erase it first. Possible problems facing PCRAM concern the high current density needed to erase the memory; however, as cell sizes decrease, the current needed will also decrease. PCM chips are expected to last several times as long as currently available Flash memory chips and may prove cheaper for mass production. Also, the production of PCM has been announced recently by both collaborations between Intel and STMicroelectronics as well as with Samsung [ , ].

These are discussed in detail in the following section. RRAM is a disruptive technology that can revolutionize the performance of products in many areas, from consumer electronics and personal computers to automotive, medical, military, and space. Among all the current memory technologies, RRAM is attracting much attention since it is compatible with the conventional semiconductor processes. Memristor-based RRAM is one of the most promising emerging memory technologies and has the potential of being a universal memory technology [ ].

It offers the potential for a cheap, simple memory that could compete across the whole spectrum of digital memories, from low-cost, low-performance applications up to universal memories capable of replacing all current market-leading technologies, such as hard disk drives, random-access memories, and Flash memories [ ]. It can exist in two distinct conductivity states, with each state being induced by applying different voltages across the device terminals.

RRAM uses materials that can be switched between two or more distinct resistance states. Many companies are investing metal oxide nanolayers switched by voltage pulses. Researchers generally think that the pulses' electric fields produce conducting filaments through the insulating oxide. Xu et al. In contrast to a conventional MOS-accessed memory cell, a memristor-based RRAM has the potential of forming a cross-point structure without using access devices, achieving an ultra-high density.

Basic RRAM cell structure. Kamiya et al. The key issue is, therefore, to reveal electronic roles in the formation and disruption of the vacancy filaments. Wang and Tseng and Lin et al. Recently, Goux et al. Although being a most promising memory element, critical issues for the future development of RRAM devices are reliable, such as data retention and memory endurance [ ].

Therefore, a statistical study of reliability, availability, and maintainability is essential for the future development of RRAM. Throughout the last few years, polymers have found growing interest as a result of the rise of a new class of nonvolatile memories. Moreover, polymer memory has the advantage of a simple fabrication process and good controllability of materials [ ].

Polymer memory could be called digital memory with the latest technology. It is not possible for a silicon-based memory to be established in less space, but it is possible for polymer memory. Ling et al. They revealed that a polymer memory stores information in a manner that is entirely different from that of silicon-based memory devices. Among the large number of emerging memory technologies, polymer memory is the leading technology. It is mainly because of its expansion capability in 3-D space [ ] since most polymers are organic materials consisting of long chains of single molecules.

Prior to polymer memory fabrication, deposition of an organic layer is usually done by the sol-gel spin coating technique. All the other necessary constituent materials are dissolved in a solvent which is then spin-coated over a substrate. When the solvent is evaporated, a thin film of material with to nm thickness is successfully deposited at bottom electrodes. Top electrodes are deposited as the final step. The conductivity of the organic layer is then changed by applying a voltage across the memory cell, allowing bits of data to be stored in the polymer memory cell.

When the polymer memory cell becomes electrically conductive, the electrons are introduced and removed. This will open up tremendous opportunities in the electronics world, where tailor-made memory materials represent an unknown territory. The nonvolatileness and other features are inbuilt at the molecular level and offers very high advantages in terms of cost. But turning polymer memory into a commercial product would not be easy. Memory technologies compete not only on storage capacity but on speed, energy consumption, and reliability.

They are likely to be limited to niche applications [ ]. In a racetrack memory, information is stored on a U-shaped nanowire as a pattern of magnetic regions with different polarities. Achieving capacities comparable to vertical RM or hard drives would require stacks of these arrays. The magnetic information itself is then pushed along the wire, past the write and read heads by applying voltage pulses to the wire ends. The magnetic pattern to speed along the nanowire, while applying a spin-polarized current, causes the data to be moved in either direction, depending on the direction of the current.

A second device at the base of the track reads the data. Data can be written and read in less than a nanosecond. A racetrack memory using hundreds of millions of nanowires would have the potential to store vast amounts of data [ , ]. In this way, the memory requires no mechanical moving of parts and it has a greater reliability and higher performance than HDDs, with theoretical nanosecond operating speeds.

For a device configuration where data storage wires are fabricated in rows on the substrate, conventional manufacturing techniques are adequate. While this layout does allow high data storage densities, it also has the disadvantage of complex fabrication methods, with so far, only 3-bit operation of the devices demonstrated [ ].

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As the access time of the data is also dependent on the position of the data on the wire, these would also be performance losses if long wires are used to increase the storage density further. The speed of operation of the devices has also been an issue during development, with much slower movement of the magnetic domains than originally predicted. This has been attributed to crystal imperfections in the permalloy wire, which inhibit the movement of the magnetic domains. Racetrack memory diagram showing an array of U-shaped magnetic nanowires.

The nanowires are arranged vertically like trees in a forest and a pair of tiny devices that read and write the data. Adopted from IBM. Researchers are already working hard on several emerging technologies, as discussed in previous sections, to pursue storage-class memories with a more traditional design than that of the racetrack memory, which places the bits in horizontal arrays.

A molecular memory is a nonvolatile data storage memory technology that uses molecular species as the data storage element, rather than, e. The molecules are packed in a highly ordered way, with one end of the molecule electrically connected to the bottom electrode and the other end of the molecule connected to the top electrode, and this molecular component is described as a molecular switch [ ]. Langmuir-Blodgett LB deposition is ideally suited for depositing the molecular layer for the fabrication of molecular memory devices [ , ].

Then, regarding the molecular memory operation, by applying a voltage between the electrodes, the conductivity of the molecules is altered, enabling data to be stored in a nonvolatile way. This process can then be reversed, and the data can be erased by applying a voltage to the opposite polarity of the memory cell. The increasing demand for nonvolatile electronic memories will grow rapidly in order to keep pace with the requirements for subsystems involved in flight demonstration projects and deep space operations.

At the same time, mass, volume, and power must be minimized for mission affordability concerning these requirements; molecular memory could be a very promising candidate to fill this need. Recently, Plafke has revealed clearly via an article that like most experimental technology that sounds so amazing that we want it right now, the molecular memory cell does not provide enough power for a commercial device [ ]. However, the area of molecular switching memory is promising, having eliminated the need for near-absolute zero temperatures and removed some of the constraints of the shape and number of layers of the molecule sheets which intend to convey that two of the biggest barriers are taken away.

Thus, molecular memory requires strong attention to work over such issues and needs immediate amendment to see the possibility of a universal memory in the future. In the last two decades, an increasing interest is observed for electronics-related devices and the search for a universal memory data storage device that combines rapid read and write speeds, high storage density, and nonvolatility is driving the investigation of new materials in the nanostructured form [ ].

As an alternative to the current Flash memory technology, a novel transistor architecture using molecular-scale nanowire memory cells holds the promise of unprecedently compact data storage. The molecular nanowire array MNW memory is fundamentally different from other semiconductor memories; information storage is achieved through the channel of a nanowire transistor that is functionalized with redox-active molecules rather than through manipulation of small amounts of charge.

It is relatively slow and lacks the random access capability, wherein data that can be randomly read and written at every byte are being actively pursued. Nanowires synthesized by chemical or physical processes are nearly perfect single-crystal structures with a small geometry and perfect surface. The channel of a nanowire transistor is functionalized with redox-active molecules. During programming, control of the voltage acting on the substrate is possible to change the oxidation and reduction states of the active molecules.

The MNW memory has advantages of low power dissipation, ultra-high density, simple fabrication process, 3-D structure, and multilevel storage, and it functions at the nanoscale with a few electrons but limited by low retention time parameter [ , ].

Emerging Memory Technologies: Design, Architecture, and Applications

Moreover, the deposition of metals onto a monolayer of molecular wires can lead to low device yield, and this problem remains a major challenge [ ]. However, mentioning the term emerging class memory, it could be expected that the MNW memory represents an important step towards the creation of molecular computers that are much smaller and could be more powerful than today's silicon-based computers.

Semiconductor memory is essential for information processing as a key part of silicon technology; semiconductor memory has been continuously scaled to achieve a higher density and better performance in accordance with Moore's law [ ]. As Flash memory approaches its scaling limit, several alternative strategies have been proposed to extend or replace the current Flash memory technology [ ]. These approaches are revolutionary, but major challenges must be overcome to achieve small memory size and aggressive technology design architecture. In addition to the engineering of trapping layers, the device performance can also be improved by using innovative nonplanar channel geometries.

Among the various nanostructure materials, semiconductor nanowire memory SNW has induced great scientific interest as possible building blocks for future nanoelectronic circuitry. The SNW memory shows high mobility, less power dissipation, and high performance. Moreover, being 3-D-stacked, the SNW memory enhances cell density and data capacity without relying on advances in process technology. The nanowire-based memory device can store data electrically and is nonvolatile, meaning it retains data when the power is turned off, like the silicon-based Flash memory found in smart phones and memory cards [ ], with minimal increase in chip size.

The SNW memory cannot hold data as long as the existing Flash, but it is slower and has fewer rewrite cycles and it could potentially be made smaller and packed together more densely. And its main advantage is that it can be made using simple processes at room temperature, which means that it can be deposited even on top of flexible plastic substrates [ ]. The SNW could, for instance, be built into a flexible display and could be packed into smaller spaces inside cell phones, MP3 players, plastic RFID tags, and credit cards.

NRAM is a carbon nanotube CNT -based memory, which works on a nanomechanical principle, rather than a change in material properties [ ]. NRAM uses carbon nanotubes for the bit cells, and the 0 or 1 is determined by the tube's physical state: up with high resistance, or down and grounded.

It is also very stable in its 0 or 1 state. CNTs are then deposited on the spacer layer, leaving them freestanding above the bottom electrodes. Unwanted CNTs are removed from the areas around the electrode, with top contacts and interconnects deposited on top of the patterned CNT layer. During the time that the CNTs are freestanding, there is no conduction path between the bottom and top electrodes and hence the memory cell is in the OFF state.

However, if a large enough voltage is applied over the cell, the nanotubes are attracted to the bottom electrode where they are held in place by van der Waals forces [ ]. The OFF state can be returned by repelling the nanotubes with the opposite electrode polarity. Nonvolatility is achieved due to the strength of the van der Waals forces overcoming the mechanical strain of the bent nanotubes, hence holding the cell in the ON state.

NRAM offers the possibility of a simple cell architecture, which could operate at much higher speeds than the conventional Flash and with low power use. Cui et al. The issues include the cost and fabrication complexity of producing the CNTs, ensuring uniform dispersions of nanotubes, and difficulties in removing nanotubes from the unwanted positions on the substrate. In , IBM developed a punch card system known as Millipede, which is a nonvolatile computer memory stored in a thin polymer sheet with nanoscopic holes to provide a simple way to store binary data [ ].

It can store hundreds of gigabytes of data per square centimeter. However, the polymer reverts to its pre-punched form over time, losing data in the process. Millipede storage technology is being pursued as a potential replacement for magnetic recording in hard drives, at the same time reducing the form factor to that of Flash media. Millipede uses thousands of tiny sharp points hence the name to punch holes in a thin plastic film. Each of the nm holes represents a single bit. The pattern of indentations is a digitized version of the data.

According to IBM, Millipede can be thought of as a nanotechnology version of the punch card data processing technology developed in the late nineteenth century [ ]. However, there are significant differences: Millipede is rewritable, and it may eventually enable storage of over 1. Storage devices based on IBM's technology can be made with existing manufacturing techniques, so they will not be expensive to make.

According to P. Vettiger, head of the Millipede project, there is not a single step in fabrication that needs to be invented. Vettiger predicts that a nanostorage device based on IBM's technology could be available as early as [ ]. Adopted from ref. The use of DNA is well known as a good model for metal NP synthesis due to its affinity to the metal ions [ ]. In recent years, DNA has also been shown to be a promising optical material with the material processing fully compatible with conventional polymer for thin-film optoelectronic applications [ , ].

The device functionally works when shining UV light on the system, which enables a light-triggered synthesis process that causes the silver atoms to cluster into nanosized particles and readies the system for data encoding. For some particular instance, the team has found that using DNA may be less expensive to process into storage devices than using traditional, inorganic materials like silicon, the researchers say [ , ].

But the UV irradiation makes the composite unable to hold a charge under a high electric field, so when the applied voltage exceeds a certain threshold, an increased amount of charge is able to pass through. Once information is written, the device appears to retain that information indefinitely. The researchers hope that the technique will be useful in the design of optical storage devices and suggest that it may have plasmonic applications as well.

Consequently, WORM memories based on DNA a biopolymer nanocomposite have emerged as an excellent candidate for next-generation information storage media because of their potential application in flexible memory devices. This work combines new advances in DNA nanotechnology with a conventional polymer fabrication platform to realize a new emerging class of DNA-based memory.

Schematic design of a memory device consisting of a thin DNA biopolymer film sandwiched between electrodes. The memory switching effect is activated upon light irradiation. Memory made from tiny islands of semiconductors - known as quantum dots - could fill a gap left by today's computer memory, allowing storage that is fast as well as long lasting. Researchers have shown that they can write information into quantum dot memory in just nanoseconds.

Computers use DRAM, for short-term memory, but data does not persist for long and must be refreshed over times per second to maintain its memory. On the other hand, Flash memory, like that used in memory cards, can store data for years without refreshing but writes information about 1, times slower than DRAM. New research shows that memory based on quantum dots can provide the best of both: long-term storage with write speeds nearly as fast as DRAM. However, these features have not been realized due to variations in dot size and lack of uniform insulator cladding layers on the dots [ ]. Incorporating QDs into the floating gate results in a reduction in charge leakage and power dissipation with enhanced programming speed.

Structure of quantum dot memory. Memory producers are also trying to develop alternative technologies that may be scalable beyond nm lithography. For true scalability beyond nm technology nodes, it is necessary to design a cross-point memory array which does not require diodes for access elements [ ]. The cross-point memory architecture could be designed such that it can be easily fabricated in multiple layers to form a stacked 3-D memory [ ].

The 3-D technology has brought to high volume an NVM where arrays of memory cells are stacked above control logic circuitry in the third dimension, and stacking 3-D memory directly over CMOS allows for high array efficiency and very small die size [ ]. The 3-D technology uses no new materials, processes, or fabrication equipment, which control logic circuitry composed of typical CMOS. The memory construction uses typical back-end processing tools, and each memory layer is a repeat of the layers below it.

Building integrated circuits vertically allows for a reduced chip footprint when compared to a traditional 2-D design, by an approximate factor of the number of layers used.


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This offers significant advantages in terms of reduced interconnect delay when routing to blocks that otherwise would have been placed laterally. The process for the 2-D cross-point array can be built into a multilayer 3-D architecture. Traditionally, a 3-D integrated circuit 3-D-IC has used more than one active device layer. While resistance-change memory cells are not active devices, they function as rectifying devices in design. Further characterization of the resistance-change material is also necessary in order to guarantee that the 3-D cross-point memory will be practical for data storage.

Also, the scalability of metal-oxide resistance-change materials beyond nm technology nodes still needs to be studied. Moreover, the programming operation is expected to be competitive with both NAND and NOR Flash in terms of speed because of the relatively low voltage requirements of resistance-change materials. If the peripheral circuitry for accommodating the write operation can be made sufficiently compact, then the 3-D cross-point memory will indeed be a viable replacement for NAND and NOR Flash in future process generations.

The basic design of a 3-D cell that consists of a vertical diode in series. Transparent and flexible electronics TFE is, today, one of the most advanced topics for a wide range of device applications, where the key component is transparent conducting oxides TCOs , which are unique materials that oxides of different origin play an important role, not only as a passive component but also as an active component [ ].

TFE is an emerging technology that employs materials including oxides, nitrides, and carbides and a device for the realization of invisible circuits for implementing next-generation transparent conducting oxides in an invisible memory generation [ ]. They are much better suited for the next revolution in electronic 3-D memory than Flash memory.

Speaking at the rd National Meeting and Exposition of the American Chemical Society, the world's largest scientific society, he said that devices with these chips could retain data despite an accidental trip through the drier or even a voyage to Mars. And with a unique 3-D internal architecture, the new chips could pack extra gigabytes of data while taking up less space [ ]. Despite the recent progress in TF-RRAM, it needs lots of work to satisfy the dual requirements of resistance to repeated bending stress and transparent properties.

Thus, it is supposed that an achievement of such TF-RRAM device will be the next step towards the realization of transparent and flexible electronic systems. We hope that FT-RRAM devices will mark a milestone in the current progress of such unique and invisible electronic systems in the near future. One-transistor one-resistor 1T1R -RRAM is also one class of emerging memory technology with impressive characteristics.

Overview This book explores the design implications of emerging, non-volatile memory NVM technologies on future computer memory hierarchy architecture designs. This book provides a holistic perspective on the topic, covering modeling, design, architecture and applications. Product Details Table of Contents.

Average Review. Write a Review. Related Searches. This Notebook is Perfect for plotting out your 3D Designs. It has Pages of Isometric It has Pages of Isometric paper with a grid of equilateral triangles each measuring. View Product. The Architecture and Memory of the Minority Quarter.

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Emerging Memory Technologies: Design, Architecture, and Applications Emerging Memory Technologies: Design, Architecture, and Applications
Emerging Memory Technologies: Design, Architecture, and Applications Emerging Memory Technologies: Design, Architecture, and Applications
Emerging Memory Technologies: Design, Architecture, and Applications Emerging Memory Technologies: Design, Architecture, and Applications
Emerging Memory Technologies: Design, Architecture, and Applications Emerging Memory Technologies: Design, Architecture, and Applications
Emerging Memory Technologies: Design, Architecture, and Applications Emerging Memory Technologies: Design, Architecture, and Applications

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