Hey, Intel and Micron: XPoint is phase-change memory, right? Or is it? Yes. No. Yes

Same Difference

While XPoint does work through a phase change, its behavior is different from PCM. Since PCM works through the relative resistance of the amorphous/crystalline material itself, it is slower to write (you have to get the state within the tolerance) and slower to read. It also suffers from wear out as the ability to be sufficiently exact breaks down over time (I am simplifying of course). On the plus side, it allows for multi-bit cells based on intermediate states.

XPoint, the phase change is just a mechanism to allow or block the wire through the cell. This means that reading and writing are much faster, and there is less wear out risk, but there are no intermediate states for multi-bit cells.

Since the behavior is different, I'm sure the marketing guy did his job and told the engineers to give it a new name and avoid the words phase change. In this case it is the right decision as knowledge of PCM would lead you away from understanding the behavior of these new cells.

Thank You, It All Makes Sense Now

Well, maybe changing something other than the phase is how they finally made it work. (And exactly what is their secret, so they have to get a good patent before they can tell you.)

But XPoint is definitely almost phase change memory.

Can they field it?

Can they build it into a product, and will the product be successful? That's the really interesting question to me. As the author noted, Intel and Micron are adding a new memory product that needs to sit in a new "spot" in a computer architecture. Where Intel thinks it should go in has me more curious than what's in the magic black box, personally.

That which we call a computer implemented invention ...

The idea of FinFETs has been around long enough for the patents to expire. When process shrinkage made FinFETs worth the effort, Intel called them 3D-transistors. I assume Intel's PCM will get a new TLA so it can be covered with fresh patents.

I'm still confused why it's so important to the article writer to prove that it's a duck. If its phase change memory, hurrah. If its not, hurrah. If its vaporware, boo.

Chicken Feet & Phoenix Claws

Very long ago somewhere east, when there is little food, people had to eat chicken feet. It doesn’t taste very good and look dirty, but it is better than grass. Then two chiefs found a tasty way to prepare them, and called it ‘Phoenix Claws’.

http://go-yumcha.blogspot.sg/2009/03/chicken-feet-aka-phoenix-claws-matter.html

<font size=”.1”> Disclaimer: All characters & events here are entirely fictional. You hereby agreed you don’t believe this article. </font>

Phase change or not ...

.. is probably going to be decided in court, and patent lawyers are going to make lots of money on that issue.