Diamond-Like Carbon Films Used in IBEX

Scientists at Sandia National Laboratory in New Mexico have created diamond-like thin carbon films which have now been used in the low energy sensors of the recently launched NASA Interstellar Boundary Explorer (IBEX). The smooth layer of film efficiently ionizes the neutral atoms created at the interstellar boundary so they can be detected by the sensors on IBEX, helping scientists to better understand phenomena such as solar wind. The researchers say their novel films might even help scientists understand how life on Earth evolved and how it could have evolved on other planets.

Sandia researcher Tom Friedmann led the project to create the films. Similar films are used by Sandia to study electron field emissions and microelectromechanical (MEMS) systems. It was essential to have a smooth surface covering the sensor to allow for the most efficient particle scattering possible.
Friedmann says he chose carbon because of its smoothness, high energy conversion efficiency and its low sputter yield, due to which it remains intact longer than many other materials. The most efficient form of carbon is diamond but it was too expensive to be used in such films and made it difficult to obtain the smoothness required for the sensor. Instead, Friedmann used a pulsed laser disposition to create the naturally smooth diamond-like film.

IBEX is in high Earth orbit 200,000 miles above the planet and well above Earth’s magnetosphere. This ensures that particles detected by IBEX were generated in the outer reaches of the solar system rather than by Earth’s magnetic field. The mission is part of NASA’s Small Explorers program and is scheduled to run for two years. No data has yet been released and so there is no indication as to how well Friedmann’s carbon films are performing in IBEX sensors.

Scientists hope IBEX with its two sensors will reveal a great deal about the interactions between solar winds traveling out from the Sun and radiation entering the solar system from the rest of the galaxy. This information, they say, may provide clues about why life developed on Earth and help astronomers look for life elsewhere.

TFOT has previously reported on other thin films including flexible, stretchable carbon nanotube films that may someday replace conventional loudspeakers. You are also welcome to check out an article on superstrong flexible aluminum oxide and polymer composite film, developed at Swiss Federal Institute of Technology in Zurich. TFOT has also reported on other interesting extraterrestrial observation tools including NASA’s Gamma-Ray Large Area Telescope (now called the Fermi Gamma-Ray Space Telescope), the High Resolution Soft X-Ray Spectrometer (to be part of Japan Aerospace Exploration Agency’s New Exploration Space X-Ray Telescope scheduled for launch in 2013), and NASA’s upcoming James Webb Space Telescope (also scheduled for launch in 2013).

You can read more about the thin carbon film in this Sandia National Laboratory press release and find more information on IBEX at its NASA project page. More information about the low energy sensor can be found in this Lockheed Martin press release.

Image icon: Artist’s rendering of IBEX (Credit: NASA/GSFC)