SoylentNews is people
SoylentNews
Startup Showcases 7 bits-per-cell Flash Storage with 10 Year Retention
Floadia Corp., a Series C startup from Japan, issued a press release this week to state that it has developed storage technology capable of seven bits-per-cell (7bpc). Still in the prototype stage, this 7bpc flash chip, likely in a WORM [(Write Once Read Many)] scenario, has an effective 10-year retention time for the data at 150C. The company says that a standard modern memory cell with this level of control would only be able to [retain] the data for around 100 seconds, and so the secret in the design is to do with a new type of flash cell they have developed.
The SONOS cell uses a distributed charge trap design relying on a Silicon-Oxide-Nitride-Oxide-Silicon layout, and the company points to an effective silicon nitride film in the middle where the charges are trapped to allow for high retention. In simple voltage program and erase cycles, the company showcases 100k+ cycles with a very low voltage drift. The oxide-nitride-oxide layers rely on SiO2 and Si3N4, the latter of which is claimed to be easy to manufacture. This allows a non-volatile SONOS cell to be used in NV-SRAM or embedded designs, such as microcontrollers.
It's actually that last point which means we're a long time from seeing this in modern NAND flash. Floadia is currently partnering with companies like Toshiba to implement the SONOS cell in a variety of microcontrollers, rather than large NAND flash deployments, at the 40nm process node as embedded flash IP with compute-in-memory properties. Those aren't at 7 bits-per-cell yet, to the effect that the company is promoting that two cells can store up to 8-bits of network weights for machine learning inference – when we get to 8 bits-per-cell, then it might be more applicable. The 10-year retention of the cell data is where it gets interesting, as embedded platforms will use algorithms with fixed weights over the lifetime of the product, except for the rare update perhaps. Even with increased longevity, Floadia doesn't go into detail regarding cyclability at 7bpc at this time.
Related: Is Octa-Level Cell (OLC) NAND Possible? We May Find Out This Year
(Score: 3, Informative) by takyon on Friday December 17 2021, @12:11PM (1 child)
I think we'll end up craving optical/holographic storage in the 100 terabyte to multi-petabyte range.
"5D" Laser-Based Polarization Vortex Storage Could Hold Hundreds of Terabytes for Billions of Years [soylentnews.org]
Microsoft Stores 75.6 GB on Glass Disc Designed to Last Thousands of Years [soylentnews.org]
Researchers Store 5 Gigabytes Using "5D" Optical Data Storage, Claim Up to 500 Terabytes Possible [soylentnews.org]
If it ends up not being rewritable, that's a nuisance, but if you can write as you go, the sheer capacity could make it so it doesn't matter.
Hopefully it would end up as a consumer technology, or cheap enough for consumers to buy. Optical discs in general have declined, high-capacity HDDs target datacenters first and can fail horribly, and nobody wants to use expensive tape drives and high-latency tape. Ideally, silly developments like 8K video cameras on smartphones or 360-degree VR video could create demand for hundreds of terabytes of consumer storage.
If you can sacrifice some density, you could pick up M-DISCs [wikipedia.org] right now. I don't know if you can trust the longevity claims though.
Other than optical, there are various universal memory [wikipedia.org] candidates that could replace DRAM, NAND, and/or HDDs, depending on the characteristics of the technology.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by deimtee on Friday December 17 2021, @04:19PM
A 500TB WORM drive as a data drive would actually a huge plus for most people. It pretty much makes them immune to ransomware.
200 million years is actually quite a long time.