Measurements from the edge: magnetic properties of thin filmsOctober 01, 2007Materials researchers at the National Institute of Standards and Technology (NIST), together with colleagues from IBM and the Massachusetts Institute of Technology, have pushed the measurement of thin films to the edge-literally-to produce the first data on how the edges of metallic thin films contribute to their magnetic properties. Their results may impact the design of future nanoscale electronics. Ferromagnetic thin films of metallic materials-ranging in thickness from fractions of a nanometer to several micrometers-are layered in patterns on a substrate (such as silicon) during the manufacture of many microelectronic devices that use magnetic properties, such as computer hard drives. While methods for measuring the magnetic properties of ferromagnetic thin films have existed for some time, there currently is no way to define those properties for the edges of the film. On a relatively large-scale device, this doesn't matter much. However, as microelectronic components get smaller and smaller, the edge becomes a bigger and bigger fraction of the surface, eventually becoming the thin film's dominant surface and the driver of its magnetic character. (Shrink a disk by half and the top surface area is reduced by a factor of four while the length of the edge is only halved.) A research team from NIST, IBM and MIT recently demonstrated a spectroscopic technique for measuring the magnetic properties of the edges of nickel-iron alloy thin films patterned in an array of parallel nanowires (called "stripes") atop a silicon disk. The researchers beamed microwaves of different frequencies over the stripes and measured the magnetic resonances that resulted. Because a thin film's edge resonates differently from its center, the researchers were able to determine which data-and subsequently, which magnetic behaviors-were attributable to the edge. In its first trials, the new technique has been used to measure how the magnetic properties of the thin film edge are affected by the thickness of the film and the processing conditions during the stripe patterning. Data gained from the study of stripes with widths of 250 to 1,000 nanometers will be used to predict the behavior of similar structures at the nanoscale level (100 nanometers or less). National Institute of Standards and Technology (NIST) |
|||||||||||||||||||||
| Related Magnetic Properties Current Events and Magnetic Properties News Articles Like little golden assassins, 'smart' nanoparticles identify, target and kill cancer cells Another weapon in the arsenal against cancer: Nanoparticles that identify, target and kill specific cancer cells while leaving healthy cells alone. New neutron studies support magnetism's role in superconductors Neutron scattering experiments performed at the Department of Energy's Oak Ridge National Laboratory give strong evidence that, if superconductivity is related to a material's magnetic properties, the same mechanisms are behind both copper-based high-temperature superconductors and the newly discovered iron-based superconductors. Study: Quantum fluctuations are key in superconductors New experiments on a recently discovered class of iron-based superconductors suggest that the ability of their electrons to conduct electricity without resistance is directly connected with the magnetic properties of those electrons. NIST researchers put a new spin on atomic musical chairs Researchers from the National Institute of Standards and Technology (NIST) and the Naval Research Laboratory have developed a new way to introduce magnetic impurities in a semiconductor crystal by prodding it with a scanning tunneling microscope (STM). Novel NIST connector uses magnets for leak-free microfluidic devices Like other users of microfluidic systems, National Institute of Standards and Technology (NIST) researcher Javier Atencia was faced with an annoying engineering problem: how to simply, reliably and most of all, tightly, connect his tiny devices to the external pumps and reservoirs delivering liquids into the system. NC State Develops Material That Could Boost Data Storage, Save Energy North Carolina State University engineers have created a new material that would allow a fingernail-size computer chip to store the equivalent of 20 high-definition DVDs or 250 million pages of text, far exceeding the storage capacities of today's computer memory systems. Physicists observe magnetism in gas for the first time An international team of physicists has for the first time observed magnetic behaviour in an atomic gas, addressing a decades-old debate as to whether it is possible for a gas or liquid to become ferromagnetic and exhibit magnetic properties. Using magnetism to turn drugs on and off Many medical conditions, such as chronic pain, cancer and diabetes, require medications that cannot be taken orally, but must be dosed intermittently, on an as-needed basis, over a long period of time. Discovery at UAB brings us nearer to making the dream of invisibility true A group of researchers from the Department of Physics at UAB have designed a device, called a dc metamaterial, which makes objects invisible under certain light - very low frequency electromagnetic waves - by making the inside of the magnetic field zero but not altering the exterior field. Unexpectedly long-range effects in advanced magnetic devices A tiny grid pattern has led materials scientists at the National Institute of Standards and Technology (NIST) and the Institute of Solid State Physics in Russia to an unexpected finding-the surprisingly strong and long-range effects of certain electromagnetic nanostructures used in data storage. More Magnetic Properties Current Events and Magnetic Properties News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||