A Laser Technique Could Improve Electronics

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In a second part of the experiment, the researchers tested the ability of the laser to selectively remove hydrogen from the surface of the silicon when other types of atoms were present, in an effort to broaden the implication of their findings. When they included deuterium atoms (a heavy form of hydrogen) on the silicon, the laser stripped away only the hydrogen, leaving the deuterium behind. (Since the deuterium atoms are heavier, they don't vibrate at the same frequency as hydrogen and are therefore invisible to the 4.8 micrometer wavelength light, Tolk explains.)

One of the next steps for the researchers, says Leonard Feldman, physics professor at Vanderbilt and a researcher on the team, is to test their bond-breaking technique on the type of silicon that has a crystal structure most commonly used in the semiconductor industry. (In the experiment, the researchers used silicon with a crystal structure that had been studied thoroughly in terms of silicon-hydrogen bond formation and breaking.) Also, he says, in order to get a broader understanding of the physical processes involved in breaking hydrogen bonds, the researchers will test materials other than silicon, such as diamond, which "tends to behave like silicon" in terms of hydrogen bonding, Tolk says.