Silicon is said to possess a good 'native' insulator: silicon dioxide. Exposing silicon to oxygen during manufacturing gives chip-makers an easy way to isolate their circuitry. Other semiconductors do not 'rust' into good insulators when exposed to oxygen, so they must be layered with additional insulators.
The research team claims that not only do both ultrathin semiconductors rust, they do so in a way that is even more desirable than silicon. They form 'high-K' insulators, which are said to enable lower power operation than is possible with silicon and its silicon oxide insulator.
The researchers also discovered that both materials were in the same optimal band gap range as silicon, meaning the energy needed to switch transistors on was in an optimally efficient range.
Not only do the new materials require less energy than silicon circuits, according to the researchers they can be shrunk to functional circuits three atoms thick.
"Engineers have been unable to make silicon transistors thinner than 5nm before the material properties begin to change in undesirable ways," said associate professor Eric Pop.
The team claims the combination of thinner circuits and high-K insulation means that these ultrathin semiconductors could be made into transistors 10 times smaller than anything possible with silicon today.
"Silicon won't go away. But for consumers this could mean much longer battery life and much more complex functionality if these semiconductors can be integrated with silicon," Pop said.
"There's more research to do, but a new path to thinner, smaller circuits – and more energy-efficient electronics – is within reach.”
