Researchers at Columbia University's School of Engineering and Applied Science have synthesized the first nanoscale molecule that offers better electrical insulation than a vacuum. To make the breakthrough the team exploited the wave nature of electrons. They made a rigid silicon-based molecule less than 1 nm in length that creates destructive interference signatures, thereby producing a novel method to block tunneling conduction at the nanoscale level and allow even smaller transistors to be fabricated.
Making transistors smaller is key to building faster and more efficient computers. Present day structures are already in the nanometer range. Progress to shrink the structure even more has stagnated somewhat in recent years because of leakage current produced by quantum mechanical tunneling at this scale.
This current occurs when the gap between two metal electrodes becomes so narrow that electrons can no longer be retained by their barriers and tunnel effects occur. It has generally been accepted that a vacuum provides the most effective barrier to tunneling but some leakage still occurs via quantum tunneling.
In collaboration between the Engineering and Chemistry departments of Columbia University and Shanghai Normal University and the University of Copenhagen, the first molecule has been synthesized that provides better electrical insulation than a vacuum at the nanometer scale. The results are published on Nature online.