Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


NIST Team Reports Method to Characterize New Insulating Materials for Microelectronics


Advance Should Speed Semiconductor Industry Search

Researchers from the Commerce Department’s National Institute of Standards and Technology (NIST) reported today they have developed methods for characterizing key structural features of porous films being eyed as insulators for the ultrathin metal wires that will connect millions of devices on future microprocessors and increase processor speed. The advance, reported today at the American Chemical Society’s national meeting in Boston, will help semiconductor manufacturers and their materials suppliers home in on the most promising "nanoporous film" candidates for shielding miles of interconnecting wire on next-generation microprocessors.

Microprocessors, or central processing units, are both the "brains" and "engines" of computers and other microelectronic devices.

To increase processor speed, semiconductor manufacturers seek to reduce chip sizes. However, size reduction introduces problems with electrical interference between circuit elements ("cross-talk"), motivating development of better insulating materials. Current insulating materials such as silicon dioxide and fluorinated silicate glass (FSG) are approaching their limits as devices are squeezed ever closer on a chip.

To prepare better insulating films, many materials suppliers are developing films interspersed with very small holes that measure about 5 nanometers (billionths of a meter) in diameter or less. Introducing nanometer-sized air bubbles lowers a material’s dielectric constant, or "k" value-a measure of insulating performance. Air, the ideal insulator, has a dielectric constant of 1. Silicon dioxide and FSG, in contrast, have values of about 4.2 and 3.7, respectively.

For several years, the NIST team has been performing a variety of measurements to help the semiconductor industry characterize potential nanoporous insulators. Working with the NIST Center for Neutron Research, materials scientists Ronald Hedden, Barry Bauer, and Hae-Jeong Lee of the NIST Polymers Division developed a neutron scattering technique for surveying minuscule holes in film samples supplied by International SEMATECH, the consortium of chipmakers. Combined with information gathered with other methods, neutron scattering measurements reveal the size and volume fraction of pores, the connectivity among pores and the density of the underlying matrix.

The "Swiss cheese" approach to developing new insulators presents some formidable challenges. To be sure, riddling a material with tiny holes (or bubbles) lowers its "k" value, but changes other important properties as well. Also to be taken into account, for example, are a candidate material’s strength and hardness, how well it adheres to different substrates, and whether it can withstand high temperatures and etch chemicals during processing.

"An ideal replacement for silicon dioxide would provide the desired level of insulation without compromising barrier properties," explains Bauer. "The more fully we can characterize the pore structure and properties of these nanoporous materials, the more straightforward the search becomes."

Bauer, Hedden and Lee led an effort to extend contrast matching-a neutron-based technique for studying bulk materials-to nanoporous thin films. They succeeded by pumping solvent vapor mixtures into a special flow-through chamber containing the films. The vapor condenses into the pores, permitting neutron scattering measurements that probe the film density while yielding valuable information about pore connectivity. The new neutron technique also can detect nanometer-sized inhomogeneities in the composition of the matrix.

Though the results are promising, the contrast-matching procedure is time-consuming, taking three to four days per sample. One goal of the team is to develop a simpler alternative that industry could use to character films faster and more cheaply. Hedden says neutron scattering measurements could be used as a benchmark to evaluate data gathered with other approaches.

As a non-regulatory agency of the U.S. Department of Commerce’s Technology Administration, NIST develops and promotes measurements, standards and technology to enhance productivity, facilitate trade and improve the quality of life. For more information on NIST, visit

Mark Bello | EurekAlert!

More articles from Power and Electrical Engineering:

nachricht Steering a fusion plasma toward stability
28.10.2016 | American Physical Society

nachricht Solid progress in carbon capture
27.10.2016 | King Abdullah University of Science & Technology (KAUST)

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel light sources made of 2D materials

Physicists from the University of Würzburg have designed a light source that emits photon pairs. Two-photon sources are particularly well suited for tap-proof data encryption. The experiment's key ingredients: a semiconductor crystal and some sticky tape.

So-called monolayers are at the heart of the research activities. These "super materials" (as the prestigious science magazine "Nature" puts it) have been...

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Steering a fusion plasma toward stability

28.10.2016 | Power and Electrical Engineering

Bioluminescent sensor causes brain cells to glow in the dark

28.10.2016 | Life Sciences

Activation of 2 genes linked to development of atherosclerosis

28.10.2016 | Life Sciences

More VideoLinks >>>