Motorola Makes Its Case for MRAM

Motorola Monday says it has broken the speed barrier for a new type of memory, which would allow computers to power on as quickly as a light switch and not have to wait for software to boot up.

The Schaumburg, Ill.-based wireless giant says it has produced a 4Mb Magnetic (or Magnetoresistive) Random Access Memory (MRAM) chip. The nonvolatile memory technology uses magnetic, rather than electronic, charges to store bits of data as is the case with DRAM and SRAM .

The chipmaker says its 256K x 16 “toggle” MRAM chip is based on a 0.18-micron five-level metal CMOS process technology with fast access times. The memory uses unidirectional programming currents with isolated write and read paths and balanced current mirror sense amplifier.

Motorola said it is now working with lead customers on performance refinements and expects to conduct broader sampling on the 4Mbit MRAM and bring the chips to market sometime next year.

“For the past several years, Motorola has led the industry in MRAM development with 256kb, 1Mbit and now 4Mbit devices,” said Dr. Claudine Simson, chief technology officer, Motorola’s Semiconductor Products Sector. “Our 4Mb MRAM chip not only showcases our technology, it will accelerate the industry’s acceptance of MRAM technology. We’ve made significant progress toward establishing a solid MRAM manufacturing technology capability.”

The 4Mbit device is currently faster than the other leading MRAM products such as IBM and Infineon, which debuted their joint 128Kbit MRAM core project fabricated with a 0.18 micron logic-based process technology, back in June.

“This is a significant advancement since Motorola’s June 2002 demonstration of a 1Mb MRAM using 0.60-micron technology,” said Semico Research vice president of Emerging Technologies Bob Merritt. “That’s like stepping over four or five process generations in little more than a year.”

Ironically it was IBM Research that pioneered the development of tiny, thin-film magnetic structures as early as 1974, which paved the way for the first super-sensitive GMR read/write heads for hard-disk drives, stimulating dramatic increases in data density.

In the late 1980s, IBM scientists made a string of key discoveries about the “giant magnetoresistive” effect in thin-film structures. These developments enabled IBM to create the Altering many of the GMR materials enabled IBM scientists to make the “magnetic tunnel junctions” that are at the heart of MRAM.

The technology has become so attractive; in 1995 the U.S. Defense Advanced Research Projects Agency (DARPA) began funding three private groups with the goal of making MRAM a general-purpose memory with high density, high speed, and low power usage. IBM, Motorola, and Honeywell led the research. Hewlett-Packard , Matsushita , NEC , Fujitsu, Toshiba, Hitachi , and Siemens also have invested in MRAM study.

IBM and Infineon have been working together for more than 10 years on new chip technologies, including traditional Dynamic RAM (DRAM), logic and embedded-DRAM technologies. In November 2000, they established a joint MRAM development program.

MRAM Good for Mobile Devices

The non-volatility attribute of MRAM carries significant implications, especially for mobile computing devices. Memory technologies like DRAM and SRAM require constant electrical power to retain stored data. When power is cut off, all data in memory is lost. A laptop computer, for example, works from a copy of its software stored in memory. When turned on, a working version of the software is copied from the hard-disk drive into memory, so the user can access it quickly. Every time the power is turned off and then back on, the process must start over. By using MRAM, the companies say a laptop could work more like other electronic devices such as a television or radio: turn the power on and the machine jumps almost instantly to life with settings just as you had left them.

Non-volatility can save power as well. Since MRAM will not need constant power to keep the data intact, it could consume much less than current random access memory technologies, extending the battery life of cell phones, handheld devices, laptops and other battery-powered products.

The high-speed attribute of MRAM means that electronic products can more quickly access data, and MRAM’s high-density means greater storage capacity.

Motorola is scheduled to present details of its “toggle” approach to MRAM at the 2003 IEEE International Electron Devices Meeting, in December.

News Around the Web