NEW YORK -- The recent memory-technology development agreement between IBM Corp. and Infineon Technologies AG has once again demonstrated the industry's continued belief in the promise of magnetic RAM, even if commercialization of the devices seems always to be just a few years off.
With a volume-production time frame of 2004 to shoot for, IBM, Infineon, and a half-dozen other companies are hoping to drive MRAM to market as a low-power, nonvolatile replacement for flash memory, DRAM, and SRAM in devices ranging from cell phones and PDAs to cache memory.
While IBM and Infineon are hunkered down at the chip research center of IBM Microelectronics in East Fishkill, N.Y., Honeywell Inc. and Motorola Inc. are hoping to spin volume quantities of MRAM through a Defense Advanced Research Projects Agency contract that is also shared by IBM. DRAM powerhouses Micron, NEC, and Samsung are said to be developing the technology, while Hewlett-Packard has a design team looking into the viability of chip-level magnetic storage.
"We have demonstrated that this new memory technology works. Now we're going ahead in the next two years to develop prototype devices to have commercial chips ready by 2004," said Saied Tehran, MRAM program manager at Motorola's Semiconductor Products Sector in Phoenix. Last spring, Motorola researchers said they were successful in producing working prototypes of high-speed 3-volt MRAMs, which had access times of 15 nanoseconds (see May 10 story).
Honeywell is developing a special radiation-resistant MRAM for military use, although Stuart Parkin, an IBM fellow at the company's Almaden Research Center in San Jose, said commercial MRAM chips have the same tolerance and are likely to compete in the military market as well.
James McKibben, vice president of sales at Tegal Corp. in Petaluma, Calif., which supplies advanced etching equipment to make MRAM chips, said the technology could be a "universal memory," supplanting most other devices. "Although more work is needed, MRAM demonstrations already have shown that thememory can be faster, offer higher densities, and operate at significantly lower power levels than most memory types today," McKibben said.
The beauty of MRAMs is their almost infinite life span, Motorola's Tehran said. Conventional flash memory, although relatively inexpensive, begins to deteriorate in the read mode after cycling up to a million times.
MRAMs can also operate at considerably lower voltage levels than most existing memory devices-on the order of millivolts. Flash and DRAM operating voltages continue to come down, according to IBM's Parkin, but he doubted any other memory type will approach MRAM in the foreseeable future.
In technology demonstrations, MRAM is using unsophisticated design processes on the order of 0.8-micron. Motorola and the IBM-Infineon joint development team said they will shift to 0.18-micron processes in the next prototype stage.
Developers expect the initial MRAM chips will come to market at 256 Mbits.