For release: Sept. 18, 2000
Contacts:
David Jiles, Metallurgy and Ceramics, (515) 294-9685
Susan Dieterle, Public Affairs, (515) 294-1405
AMES, Iowa -- Imagine sitting down to a personal computer that stores 10-50 times more information than today's top models, doesn't lose data during power interruptions and starts up immediately without needing the traditional "boot-up" process.
Breakthroughs such as these are being explored in the rapidly growing field of magnetoelectronics, which combines microelectronics and magnetics to create new technologies that will quench the public's growing thirst for greater data-storage capacities on computers.
Scientists at the U.S. Department of Energy's Ames Laboratory and Iowa State University will become part of those research efforts, thanks to a $530,000 grant from the Roy J. Carver Charitable Trust to establish a magnetoelectronics laboratory.
The grant was awarded in June to David Jiles and John Snyder, who are researchers at both Ames Laboratory and ISU. They are reviewing bids on equipment for the new lab, which will be located in Ames Laboratory's Metals Development building on the north side of ISU's campus. Jiles said he anticipates having the lab space renovated and the equipment in place in about six months.
"Magnetoelectronics is a very, very hot area. We've all got computers and we all want to be able to store more and more data on them," Jiles said. "Ames Laboratory and Iowa State need to get into this area because there's a huge market for this type of cutting-edge technology."
Much of the work in the new lab will involve using an ion-beam deposition system to produce materials in the form of thin films for technologies that will expand computer data-storage capacities.
Jiles said one application for the thin films would be "giant magnetoresistive," or GMR, devices that are being used to read increasingly smaller bits of information from a computer's hard drive where data, such as word-processing files, are stored. GMR materials undergo dramatic changes in their electrical resistance in response to relatively small changes in the magnetic field surrounding them. This property is useful in data-storage technologies because computer hard drives are made of magnetic disks.
Many personal computers available today have disks capable of storing 10 gigabits of information per square inch. Creating higher-density disks that could store 100-500 gigabits of information per square inch will require condensing the data into smaller bits. This, in turn, will trigger the need for smaller "read-heads" to read the data. "You can't simply shrink down the existing read-head technology because it won't work," Jiles said. "Other technologies have to be brought in."
Placing a smaller GMR device on the read-head would help solve the problem, Jiles said. The tiny devices -- so small they can only be seen with a magnifying glass -- consist of alternating thin-film layers of magnetic and nonmagnetic materials. The changes in the magnetic field emanating from the tracks on the hard disk cause changes in the electrical resistance of the GMR device, enabling the read-head to detect and read the data. "GMR devices also use less power than the old technology, so that gives us smaller read-heads that are more efficient and can handle smaller bits on the disks," he added.
Another use for thin films would be the creation of small structures that could replace the semiconductor technology now used for a computer's random access memory, or RAM, which serves a similar function to the short-term memory of the human mind. RAM holds recent software applications nearby for easy access and allows users to read data from the memory and write new data into the memory. Most RAM is volatile, meaning that it needs a constant power supply. If power is interrupted, the computer must be restarted and some data may be lost. However, researchers are working on magnetic memory devices that wouldn't be affected by power interruptions.
Jiles said the devices, known as magnetic tunnel junctions, consist of a thin insulating film sandwiched between two magnetic films. "Research has shown that this type of device could be used to store data that's nonvolatile," he said. "Right now, if I pull the plug on my computer and then plug it back in, I would lose some of the data and I would have to wait for the computer to boot up. If you had nonvolatile memory, you wouldn't lose the data. And as soon as you switch your computer on, the data would come straight up without needing to reboot."
Jiles said the new lab will enable researchers and students from Ames Laboratory and ISU to work on developing reliable magnetic tunnel junctions that have controllable electrical resistance. Production of these devices could be difficult because the traditional method of reducing the resistance is to make the insulating layer thinner. But if the layer -- sometimes only two atoms thick -- has gaps, the device will short out. "We have some ideas on how to lower the resistance while improving the reliability," he said.
Jiles said the research that will be conducted in the new lab could also create opportunities for working with companies and other scientific organizations. "We would like to get additional grants and contracts so that we can continue building other projects around this work," he said.
The Carver Charitable Trust is the largest private foundation in Iowa, awarding grants that total more than $14 million annually in support of scientific research, scholarships, general education and other issues related to the needs of youth. During the past 12 years, the Carver Trust has awarded more than $13.5 million to support scientific research and educational initiatives at ISU.
Ames Laboratory is operated for the Department of Energy by ISU. The Lab conducts research into various areas of national concern, including energy resources, high-speed computer design, environmental cleanup and restoration, and the synthesis and study of new materials.
(Note: David Jiles is a senior physicist at Ames Laboratory. He is also an ISU professor of both materials science and engineering, and electrical and computer engineering. John Snyder is an associate scientist at Ames Lab and an ISU adjunct assistant professor of materials science and engineering.)
Last revision: 9/15/00 sd