Category: Resistive RAM RRAM

Something that distinguishes the Emerging Memory report that Tom Coughlin and I recently published is the depth in which we cover in the field.  This is not measured in pages, but in the topics that we cover.  For example, this blog post, excerpted from the report, covers the changes in tooling that will be necessary to allow a standard CMOS wafer fabrication plant (a “fab”) to produce an emerging memory technology, and the impact that this is likely to have on the market for semiconductor tools.

All of the emerging memory technologies covered in the Memory Guy’s previous post share certain things in common.  One of them is that they are built between metal layers, rather than in the silicon CMOS substrate itself (with the possible exception of the hafnium oxide FRAM.)

This means that the tooling required for any of these technologies will bear a strong resemblance to that used by any of the others.  For the most part these tools will be used for deposition and etch.  The lithography requirements will be satisfied by the tools used to pattern the metal layers.

The process flow in this figure sheds some light on the steps that Continue reading “Emerging Memories Today: Process Equipment Requirements”

Here in the US we use an extremely odd expression.  If there are multiple varieties of an item we commonly say: “There are more of them than you can shake a stick at!”  This is a very lengthy way to say: “numerous.”  (I don’t believe that ANYONE understands how that expression became a part of our vernacular!)  Although The Memory Guy isn’t normally seen shaking a stick, I find it an apt way to describe the numerous new memory technologies that are being pioneered today.  There are certainly lots of them!

This post is intended to be very high-level technical description of today’s leading emerging memory technologies.  These are excerpts of the in-depth descriptions that can be found in our recently-released report: Emerging Memories Poised to Explode.

PCM: Also known as PRAM, Phase-Change Memory technology is based upon a material that can be either amorphous or crystalline at normal ambient temperatures.  The crystalline state has a low resistance and the amorphous state has a high resistance.  This is controlled by melting the bit cell by passing a current though it and then allowing it to cool at different rates.

In chemistry and physics, anything with a Continue reading “Emerging Memories Today: The Technologies: MRAM, ReRAM, PCM/XPoint, FRAM, etc.”

Non-silicon memory technologies have been studied for about as long as have silicon-based technologies, but the silicon technologies have always been preferred.  Why is that, and why should anything change?

This is a question that The Memory Guy is often asked.  The answer is relatively simple.

Silicon memory technologies benefit from the fact that they have always been manufactured on process technologies that are nearly identical to those used to produce CMOS logic, and can therefore take advantage of the advancements that are jointly developed for both memory and logic processes.  In fact, before the middle 1980s, logic and memory processes were identical.  It wasn’t until then that the memory market grew large enough (over $5 billion/year) that it could support any additional process development on its own.

Even so, memory processes and logic processes are more similar than different.  This synergy between memory and logic continues to reduce the process development cost for both memories and logic.

Emerging memories depart from Continue reading “Emerging Memories Today: Why Emerging Memories are Necessary”