backtop


Print 10 comment(s) - last by BirdDad.. on Dec 16 at 7:27 PM


Diagram of test setup

Micrograph of test setup

Closeup of test setup

Cross-section of test setup

Closeup cross-section of phase change bridge
A new memory technology using semiconductor alloy is faster, smaller and more resilient than flash

Scientists from IBM, Macronix and Qimonda today disclosed joint research results that detail a new type of computer memory with the potential to be the successor to flash memory chips. The advancement is "phase-change" non-volatile memory, which appears to be much faster and can be scaled to dimensions smaller than flash. Non-volatile memories do not require electrical power to retain their information. By combining non-volatility with good performance and reliability, this phase-change technology may one day be a universal memory for mobile applications.

Working together at IBM Research labs on both U.S. coasts, the scientists designed, built and demonstrated a prototype phase-change memory device that switched more than 500 times faster than flash while using less than one-half the power to write data into a cell. The device’s cross-section is a minuscule 3 by 20 nanometers in size, far smaller than flash can be built today and equivalent to the industry’s chip-making capabilities targeted for 2015. This new result shows that unlike flash, phase-change memory technology can improve as it gets smaller with Moore’s Law advancements.

Flash memory cells, while also non-volatile, degrade and become unreliable after being rewritten about 100,000 times. This is not a problem for many consumer uses, but is a showstopper in applications that must be frequently rewritten, such as computer main memories or the buffer memories in network storage systems. A third concern for flash’s future is that it may become extremely difficult to keep its current cell design non-volatile as designs shrink below 45 nanometers.

The IBM/Macronix/Qimonda joint project’s phase-change memory achievement is important because it demonstrates a new non-volatile phase-change material that can switch more than 500 times faster than flash memory, with less than one-half the power consumption, and most significantly, achieves these desirable properties when scaled down to at least the 22-nanometer node, two chip-processing generations beyond floating-gate flash’s predicted brick wall.

At the heart of phase-change memory is a tiny chunk of a semiconductor alloy that can be changed rapidly between an ordered, crystalline phase having lower electrical resistance to a disordered, amorphous phase with much higher electrical resistance. Because no electrical power is required to maintain either phase of the material, phase-change memory is non-volatile.

The material’s phase is set by the amplitude and duration of an electrical pulse that heats the material. When heated to a temperature just above melting, the alloy’s energized atoms move around into random arrangements. Suddenly stopping the electrical pulse freezes the atoms into a random, amorphous phase. Turning the pulse off more gradually – over about 10 nanoseconds – allows enough time for the atoms to rearrange themselves back into the well-ordered crystalline phase they prefer.

The new memory material is a germanium-antimony alloy (GeSb) to which small amounts of other elements have been added (doped) to enhance its properties. Simulation studies enabled the researchers to fine-tune and optimize the material’s properties and to study the details of its crystallization behavior. A patent has been filed covering the composition of the new material.

The view a couple animations of how phase-change memory works, click here. The technical details of this research will be presented this week at the IEEE’s 2006 International Electron Devices Meeting in San Francisco.



Comments     Threshold


This article is over a month old, voting and posting comments is disabled

The 3nm layer ....
By Almadenmike on 12/12/2006 4:11:07 AM , Rating: 2
...is created by sputter deposition, not by lithography. Such processes have been used for about 10 years (or more) to deposit atom-thin layers for mass-produced commercial devices such as the GMR heads used in disk drives.




RE: The 3nm layer ....
By Mudvillager on 12/12/2006 4:25:37 AM , Rating: 2
Why isn't sputter deposition used when creating CPU's then? (Like I said in my previous post I know nothing about nano tech.)


RE: The 3nm layer ....
By KristopherKubicki (blog) on 12/12/2006 8:15:06 AM , Rating: 2
The difference here is that they are creating a flat layer as opposed to a trace. When we say processor is 65nm wide we mean the interconnects are that wide. It's sort of like vertical vs horizontal.


"There is a single light of science, and to brighten it anywhere is to brighten it everywhere." -- Isaac Asimov

Related Articles
Solid-state Drives Ready for Prime Time
November 15, 2006, 3:45 PM













botimage
Copyright 2014 DailyTech LLC. - RSS Feed | Advertise | About Us | Ethics | FAQ | Terms, Conditions & Privacy Information | Kristopher Kubicki