Wiley has recently published a new book by Betty Prince titled Vertical 3D NAND Technologies that is one to consider if you want to bring yourself up to speed on recent research behind today’s and tomorrow’s 3D memory technologies.
For those who haven’t previously encountered Dr. Prince, she is the author of a number of key books covering memory design and holds memory patents written over her 30-year career in the field.
The book provides capsule summaries of over 360 papers and articles from scholarly journals on the subject of 3D memories, including DRAM, NAND flash, and stacked chips.
These papers are organized into Continue reading “New Book: Vertical 3D Memory Technologies”
Some time ago The Memory Guy was asked by Numonyx (later acquired by Micron) to put together an online course for EE Times on memory technologies, explaining how each one works and where it is used.
Although the course was very well received, I never posted a link to it on The Memory Guy blog. This post is intended to correct that error.
The course runs 75 minutes and covers the basics of DRAM, non-volatile RAM, SRAM, NAND flash, NOR flash, mask ROM, and EEPROM. It explains each technology’s advances in size, cost and performance, leading up to the development of Continue reading “Fundamentals of Memory – Free Online Course”
Crossbar, Inc. has come out of stealth mode with a fascinating new alternative memory technology. Furthermore, the company says that a working memory array has been produced at a commercial fab.
Crossbar says that the technology can put a terabyte onto a single chip. The company has already measured filaments as thin as 6nm, and is confident that it can be shrunk further and that it will support multilevel cells.
Crossbar’s device is a silver filament ReRAM with a difference. For one, the silver filaments are in standard silicon dioxide, probably the most Continue reading “Crossbar’s Radical New Memory Technology”
It’s not often that a small private firm acquires a part of a larger public firm, but that’s what happened today with Atmel and Adesto. Adesto, a manufacturer of alternative memory technology, has purchased Atmel’s serial NOR flash business for an undisclosed sum.
The transaction covers the Atmel “Data Flash” and “BIOS Flash” product families and the employees supporting those products. Atmel has retained its Serial EEPROM, Crypto and Digital Temperature Sensor memory product lines and plans to continue to invest in those businesses.
This is not a small thing. Serial NOR now accounts for roughly Continue reading “Adesto Acquires Atmel’s Serial NOR Business”
Everyone knows that flash memory is about to hit its scaling limit – it’s right around the corner. We’re ready for it because it’s been right around the corner for more than a decade now. It’s so close we can taste it.
When will it happen?
One thing that is quite clear is that nobody knows when NAND flash will stop scaling. Everyone knows that it’s soon, but researchers continue to find ways to push the technology another couple of process nodes past where anyone thought it could possibly go, and they have been doing this since Continue reading “The End of Flash Scaling”
During this week’s International Solid State Circuits Conference (ISSCC) I learned some very valuable information about memories built using crosspoint matrices.
Since ISSCC is a conference at which you meet the best and brightest minds in the industry it should come as no surprise that I was able to meet with several of the most forward-thinking industry luminaries. One of them explained to me a very fundamental difficulty with resistive RAMs (ReRAMs): These devices require a forward current to be programmed to a “1” and a reverse current to be set to a zero. This goes against the ideal crosspoint memory design in which a bit would consist of nothing more than a diode in series with a memory element. By inserting a diode, the current can only run in one direction, so a bit can be programmed or it can be erased, but not both. This is called Continue reading “How Do You Make a ReRAM Work?”
Rambus announced that the company has acquired privately-held Unity Semiconductor, an alternative memory technology company for $35 million. Unity employees have joined Rambus and will continue to develop next-generation nonvolatile memory.
Unity has an interesting technology that has caught the eye of some leading memory firms, including Micron, who had an exclusive right to Unity’s technology. The company’s CMOx is based on oxygen ions moving within a semiconducting material. It’s one species of resistive RAM.
Although Unity has been trying for years to manufacture very high density nonvolatile memory chips, The Memory Guy is not aware that the company has yet produced the chips they have set out to make.
Continue reading “Rambus Acquires Unity Semiconductor”
Elpida announced the development of a high-speed 64Mb non-volatile resistance memory (ReRAM) prototype using a 50nm process. The device was jointly developed with the New Energy and Industrial Technology Development Organization (NEDO), a Japanese-funded public institution.
Elpida will conduct further ReRAM development with Sharp Corporation, the National Institute of Advanced Industrial Science and Technology (AIST, another Japanese public institution) and the University of Tokyo.
It’s encouraging to see that Elpida still has its eye on projects into 2013 and beyond. The company is rumored to be working feverishly to find ways to stay in business through this year. Today’s DRAM market is a challenging one!
Continue reading “Elpida ReRAM Prototype”