Chalcogenide Selectors and Oxide Memory Move Towards 1Gbit

Photo of Ron Neale, Renowned Phase-Change Memory ExpertIn this post contributor Ron Neale looks deeper into a paper delivered by CEA-Leti at December’s 2019 IEDM conference, evaluating its fundamental thesis that an OTS selector is suitable for high-density memory arrays.  Another interesting aspect of this same paper was the subject of an earlier post.


One eye catcher at IEDM 2019 was a paper from a team in France at CEA-Leti, Minatec, Grenoble, IMEP LAHC CNRS and INL CNRS, INSA Lyon, by D. Alfaro Robayo et al titled: Reliability and Variability of 1S1R OxRAM-OTS for High Density Crossbar Integration.  I discussed another aspect of Continue reading “Chalcogenide Selectors and Oxide Memory Move Towards 1Gbit”

Observations on the “Universal Law” for NV Memory Cells

Photo of Ron Neale, Renowned Phase-Change Memory ExpertRon Neale returns to The Memory Guy blog to discuss a “Universal Law” about memory elements and selectors that was presented by CEA Leti at the IEEE’s 2019 IEDM conference last December.


At IEDM 2019 D. Alfaro Robayo et al presented a paper titled: Reliability and Variability of 1S1R OxRAM-OTS for High Density Crossbar Integration that had a rather interesting claim of a “Universal Law”.  It is possible that some links to the past might help to provide an explanation for Continue reading “Observations on the “Universal Law” for NV Memory Cells”

Original PCM Article from 1970

For a number of years The Memory Guy has wanted to find a copy of the 1970 article, published in Electronics magazine, in which Intel’s Gordon Moore and two authors from Energy Conversion Devices, Ron Neale and D.L. Nelson, showed that PCM could be used as a memory device.  After all, this is the technology behind Micron & Intel’s 3D XPoint Memory.

The cover of the magazine (this post’s graphic) has been used by Intel to promote its PCM or PRAM chips before those were spun off to Numonyx (now a part of Micron).  Intel, though, didn’t appear to have anything to share but the cover photo.

Electronics magazine went out of business in 1995, and that makes the task of finding archive copies more challenging.

It recently occurred to me that the best person to ask might be the article’s lead author, Ron Neale, who has been a regular contributor to EE Times and who now also contributes blog posts to The Memory Guy.

I was astounded to discover that Continue reading “Original PCM Article from 1970”

Micron PCM Enters Mass Production

Cover of Electronics Magazine, 28 September, 1970, with Intel PCM articleAfter years of prototyping Micron Technology claims to be the first to introduce production volumes of Phase-Change Memory, or PCM.  This memory, also known as PRAM, has long been positioned as a contender to replace flash once flash reaches its scaling limit.  Rather than use electrons to store a bit, PCM uses a type of glass that is conductive when in a crystalline state and resistive when amorphous, two states that are relatively easy to control.  The size of the bits can shrink to a very small dimensions, allowing PCM to scale into the single-digit number of nanometers, which most folks today believe to be beyond the realm of flash.

This product began its life at Intel, then followed the Numonyx spin-off, and was taken over by Micron when it acquired Numonyx.  In fact, Intel got into PCM very early on – this post’s graphic is the cover of an Electronics Magazine from September 1970 with an Intel story, written by Gordon Moore, telling about a 128-bit PCM research chip.

So far only three companies have produced samples Continue reading “Micron PCM Enters Mass Production”