Philips announces memory tech breakthrough

hmurchison

http://www.eetimes.com/news/latest/s...leID=159900731



"The holy grail of the embedded memory industry, a so-called unified memory that replaces all other types, combines the speed of SRAM with the memory density of DRAM and the non-volatility of Flash. Philips' new phase-change line-cell technology is a significant step towards this goal," said Karen Attenborough, project leader of the Scalable Unified Memory project at Philips Research, in a statement.



I want that Holy Grail

groverat

Attention THT or Eskimo, please pick up the white courtesy phone and translate this stuff for us.

hmurchison

Quote:

Originally posted by groverat

Attention THT or Eskimo, please pick up the white courtesy phone and translate this stuff for us.

Thank you...you see mums was the word from me.

splinemodel

Basically, a Phillips research team developed a high-speed, low voltage flash memory. It would appear, though, that it's not merely flash memory, which uses a particular electronic architecture, but rather an advanced material (In this case it's Silicon that's "alloyed" with Tellurium and Antimony) that will not lose its memory when the power goes off.



In other words, it's like flex-frames but for computer memory. Given the fact that similar elements are used for "memory-metals" (metals that will return to their cast shapes under heat), it seems very likely that this is indeed how the memory works. Of course, voltage is used instead of heat, but it appears to be a similar phenomenon. I suggest picking up the issue of Nature mentioned in the EETimes article if you're still curious.

eskimo

Quote:

Originally posted by groverat

Attention THT or Eskimo, please pick up the white courtesy phone and translate this stuff for us.

The amazing thing is this is the first time i've visited AI in probably 6 months and I happened to see your post



So there are 3 main types of memory that these people are all trying to merge together with one 'holy grail' technology: SRAM, DRAM, and Flash



SRAM is extremely fast, faster than DRAM and orders of magnitude faster than Flash. SRAM loses it's memory when power is removed and takes 6 transistors to form a memory cell. DRAM is somewhat fast, this is what your computer uses as it's main memory. It is very compact only requiring 1 transistor and 1 capacitor (which we usually stack on top of the transistor or bury in a trench below). It also loses its memory when power is removed. Flash memory is fairly dense using a complex dual layered transistor. Flash memory holds it's memory when power is not applied. Unfortunately due to the voltages required to write and erase the charge flash memory is very slow, it's a destructive meaning after 100,000 to 10,000,000 cycles it becomes unreliable, and you can't directly write/erase a memory address. You have to do it in blocks/pages sort of like a hard drive.



There are variations on phase change memory most use arrays of single transistors to access the memory cell portions just like in DRAM allowing for very dense memory elements.



Each transistor is attached electrically to a layer of material (in this case antimony-telluride) which was deposited as an amorphous and when exposed to a sufficient voltage will align into a crystalline format. The phase change material exhibits different resistance to electrical current in amorphous and crystal states. So much like how DRAM can sense the charge on the capacitor through the bit-line sense amps you can sense whether a particular portion of the phase change material is crystal '1' or amorphous '0'.



Using a different voltage/polarity you can change the material back into its amorphous state. You've effectively erased the '1' and turned it back into a '0'.



If the write/erase voltages can be made small enough then you can perform the process very quickly, quick enough to compete with DRAM or perhaps even SRAM. Since the change in material properties is physical in nature if the power is turned off the material will stay in it's current amorphous or crystalline format. This means it's non-volatile, your memory doesn't get erased when you turn off the power. And this is a fairly non-destructive process so the memory can be used far longer than say Flash.



All the major players in the industry are looking at phase change memories but there are a lot of challenges and no one has mastered it yet. Many question whether we can ever make it fast enough to actually surpass DRAM and SRAM or if it will just end up being really fast, reliable flash memory.

groverat

Thanks to two very informative posts I know kind of understand what's going on! Thanks guys.



Question:

Will the higher density make it more feasible as a replacement for storage drives than a replacement for existing RAM technologies?