Skip to main content

Researchers Create Non-Volatile Memory as Fast as DRAM and 100x as Efficient

(Image credit: Shutterstock)

Researchers from the University of Lancaster in the UK have succeeded in their efforts to create a type of non-volatile flash memory that is as fast as DRAM but uses just 1% of the energy that modern-day NAND or DRAM memory needs to write bits of data. The memory is called UK III-V Memory, as reported by ElectronicsWeekly

The power usage required is about 10 to the power of -17 Joules for a gate built on the 20nm lithographic process. The UK III-V memory's transistors will have a typically-off state, and charging a gate would take about 5ns with depletion taking 3ns, both of which are very respectable figures. It's likely that once in a product through a controller these figures would be a tad higher, but that would be a worthwhile trade-off for the gained efficiency. 

The development is still in the stage of single transistors, so translating this to a fully-fledged commercial product is still a long ways away. Nevertheless, the achievement to build non-volatile memory that is this efficient and fast enough to compete with DRAM is quite the achievement.

“The channel exploits the unusual [type-III] band alignment of In(Ga)As and GaSb, where the conduction band of InAs is below the valence band of GaSb," lead researching Professor Manus Hayne told Electronics Weekly.

"This means that even in the absence of doping electrons will flow from the full valence band of the GaSb into the conduction band of the InAs channel. This was the case before, but here we have made the In(Ga)As channel narrow so that confinement pushes the energy of the channel state up to just above the GaSb valence band, such that it is unoccupied and normally-off, unless a suitable voltage is applied. This allows a readout that is similar to flash and should deliver far superior 1-0 contrast to our previous devices allowing them to be connected in a fully-addressable array." 

Having non-volatile memory as fast as DRAM is interesting because it can be used to build PCs that can maintain the data we currently keep in RAM when the system is fully switched off and can, therefore, resume in an instant from where you left off from a full-off state. This would eliminate the need for sleep states and also allow systems to power down the RAM when they are idling, further reducing power consumption.

The question that comes to mind is whether the UK III-V memory can handle the repeated re-writes to DRAM is typically subjected. If wear is an issue, that could crush any dreams of a computer with non-volatile RAM.

  • DavidC1
    The problem is neither performance nor the nonvolatile aspect of it.

    The problem is cost. DRAM has advantages of absolutely massive scale. Every computing system in the world uses it, be it notebooks, desktops, tablets, smartphones, IoT devices, services, even your routers and Alexa devices.

    That scale allowed it to hit other "DRAM killers" with the speed and brute force of a speeding freight train. That's why they all died off. Not because they were technically inferior.
    Reply
  • TwoSpoons100
    The real cost is in the materials - silicon is cheaper than III-V semiconductors.
    There will be a niche market for non-volatile high speed memory though.
    Reply
  • bit_user
    DavidC1 said:
    The problem is cost.
    Yeah, I was wondering how the density compares.

    If the density is good enough, perhaps this stuff could challenge Intel/Micron's 3D XPoint.
    Reply
  • bit_user
    TwoSpoons100 said:
    There will be a niche market for non-volatile high speed memory though.
    What about using it for cache, in mobile chips? Currently, when mobile CPU cores drop into low-power state, they flush their caches and turn them off. However, if you have some nonvolatile memory, then you'd get the same benefit without the penalty of having to re-read data when the core wakes up.
    Reply
  • DavidC1
    TwoSpoons100 said:
    The real cost is in the materials - silicon is cheaper than III-V semiconductors.
    There will be a niche market for non-volatile high speed memory though.

    When the volume is high enough, it won't matter as much. Material costs are only significant when the volume starts being comparable.

    A newcomer needs a significant advantage to beat the incumbent. Heck, NAND flash used to be more expensive than DRAM per bit until the past 15 years. Yet its 1-2 orders of magnitude better in density.

    bit_user said:
    Yeah, I was wondering how the density compares.

    If the density is good enough, perhaps this stuff could challenge Intel/Micron's 3D XPoint.

    There are always trade-offs. Western Digital had a graph of the tradeoffs of various different memory types.

    Basically, DRAM is fastest because its volatile, and it has extremely high endurance. Flash is slow, but its very persistent and very low persistence. Even for 3D XPoint Micron had a presentation where they said a version could be made where its more expensive/fast/less persistent vs less expensive/slower/greater persistency.

    Many will fail, as it has in the past.
    Reply
  • Olle P
    DavidC1 said:
    The problem is cost. DRAM has advantages of absolutely massive scale. ...
    You don't use DRAM for SSDs, do you?
    What I see here is essentially an SSD with the speed of DRAM.
    Given that there isn't a (significantly) limited number of writings possible, which we don't know yet, it might be possible to use this new memory as a combined storage an RAM unit!
    Reply
  • ProfQuatermass
    The trouble with this sort of News, is we get reports of this type of fast storage every few years and yet still no actual product.
    Let's wait until it's launched? :eek:
    Reply
  • mradr
    ProfQuatermass said:
    The trouble with this sort of News, is we get reports of this type of fast storage every few years and yet still no actual product.
    Let's wait until it's launched? :eek:
    Not true, SSDs, Intel Opt, etc are some of those faster memory that was talk about. Now we even have a faster interconnection with Gen4 and 5 on the way.

    With that said - this new memory to make it to market fast enough still has to meet:
    Easy to scale
    Cost of materials
    Easy manufacturing
    Performance Scale ( long as it is with in reason of DRAM )Mostly, for scale of manufacturing, we can just replace it in small scale areas such as for cache drives or for the DRAM found on SSDs/HDD. The big cost though will be what does it cost and the yields to creating it. If it isn't too complex to create a layer of them and if they can be stack - then you already have a winner that will start replacing DRAM/NAND products pretty quickly. As far as production goes - I am sure companies would love to manufacture the stuff if it offers more for less. Sure it wont be a over night thing - but if it can use today's manufacturing equipment then you could see it in 6 months far faster if they have to create a new plant or 3-5 years. It wouldn't even have to beat DRAM in terms of being the fastest - long it is with in reason - it still would be faster than going over a wire to read data from another device thus could see its head pop up almost anywhere on board for the MB, CPU, and GPU. They will continue to use DRAM I am sure for main memory use - but having a way to store something longer terms does translate to way faster performance than something you have to fetch for.

    For SSD replacement:
    Needs to be cheap or little higher or near about the same current cost per Gig (obs, its faster and new tech will make it start off a lot higher)
    Scale and materials have to be easy to double up or scale down to require less materials needs
    Complexity is just base off time - the problem is making sure yields are high enough for that given amount of time. Thus, it needs to be either simple - or the yields to storage mass just needs to be better than current flash memory can provide.
    Reply