IBM and Infineon Technologies AG have made a big leap forward in the development of a memory chip that could lead to “instant-on” computers that are smaller and more powerful.
At the VSLI Symposia in Kyoto, Japan, on Tuesday, the two companies are presenting a paper in which they say they have been able to integrate magnetic memory components into a high-performance logic base.
The move gives IBM and Infineon a leg up in the development of magnetic random access memory, or MRAM, and could lead to the commercialization of the technology by 2005, said Bill Gallagher, manager of magnetoelectronics at IBM Research.
“It puts the memory closer to the logic base, which means faster access to memory,” Gallagher said in an interview with eWEEK.
MRAM is one of a number of initiatives companies are undertaking to design new memory chips. IBM and Infineon are working on one project, while a number of other companies, including Motorola Corp., are working on other MRAM projects.
But there also are other initiatives under way outside of MRAM, including Intel Corp.s work with Ovonics Unified Memory; ferroelectric RAM, or feRAM, by Texas Instruments; and polymer memory, which is being looked at by, among others, Intel and Advanced Micro Devices Inc.
Gallagher said there are a number of advantages to MRAM, the first of which is that it uses magnetic—rather than electronic—charges to store bits of data. This is done by controlling the spin of captured electrons. According to Gallagher, this technology could lead to portable devices that not only can store more data, but also access it faster, all the while using less battery power. It also could be used to consolidate the number of chips needed in a device by combining the storage capacity of DRAM (dynamic RAM), the speed of SRAM (static RAM) and the non-volatility of flash memory.
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The result is that where devices now need multiple memory chips to meet these goals, in the future they would only need one MRAM chip, Gallagher said.
Also, unlike electronic memory chips, the non-volatile MRAM chips can retain data even when power to the device is turned off. That means that PCs and other computers could boot up immediately—similar to turning on a light switch, Gallagher said—rather than having to wait for software to load up. That also will save power, since a device does not need a constant flow of power to keep the data intact.
At the event in Japan, IBM and Infineon officials unveiled a high-speed 128K-bit MRAM core built with a 0.18-micron process. Using this process, the two companies created an MRAM memory cell size of 1.4 square microns—about 20 million times smaller than an average pencil eraser top, according to IBM. Even at this size, the engineers were able to control memory reading and writing to the chip.
The writing capability is one of the key differentiators between MRAM and flash memory, which is used in mobile devices, Gallagher said. Information can be written to flash about 100,000 times before its capability begins to break down, he said. In contrast, MRAM theoretically could be written to without limitation. Gallagher said tests have shown that it can be written to at least 680 million times.
Getting the memory onto the logic base was an important hurdle in the development of MRAM, he said. The work now will focus on pushing the technology toward commercialization, he said.
IBM and Infineon have been working together on MRAM since creating a joint development program in November 2000.
