Adding carbon turns an insulating material into an ultrathin chip material, a step toward chips one atom thick
University of Tokyo researchers grew the one-atom-thick material across a 2-inch wafer and built 224 working transistors. A full circuit has not been shown yet.
Researchers led by the University of Tokyo have turned boron nitride, a material that normally blocks electricity, into a one-atom-thick material that can carry it in a controlled way, and grown it across a whole 2-inch wafer, they reported in the journal Nature, according to a university release on Tuesday.
Why it matters
The chips in phones and computers are built from billions of tiny switches called transistors, mostly made of silicon. Chips need two kinds that work as a pair: n-type transistors, which carry current with electrons, and p-type transistors, which carry current with “holes,” the gaps left when electrons are missing. Pairing them is what keeps chips from wasting power.
As silicon transistors approach their size limits, researchers are studying 2D materials, crystals just one or a few atoms thick, which could allow even smaller switches. Good n-type 2D materials have advanced quickly, but p-type ones that can be grown over large areas have been scarce, which the researchers call a major obstacle to building 2D chips.
What the team did
Boron nitride is a flat, honeycomb-like sheet of boron and nitrogen atoms. The team mixed carbon atoms into the sheet as it grew, much as chipmakers add small amounts of other elements to silicon to change how it conducts. The result, called boron carbon nitride, behaved as a p-type semiconductor. They grew a continuous single layer on copper across a 2-inch wafer by carefully controlling two starting chemicals so the boron, carbon and nitrogen arrived at the surface in the right balance.
The team built 224 transistors from three separate batches. They switched on and off cleanly, with on-current about 100 million times higher than off-current, and the results were consistent across the wafer and batches, the researchers said.
Limitations
The team has not yet paired the new p-type transistors with n-type ones to build a complete circuit. Next steps include better control of where the carbon goes, growing the material at lower temperatures and developing processes that factories could use, the release says. That means any use in commercial chips is likely years away. Researchers in Taiwan and elsewhere in Japan also worked on the study.
Sources: University of Tokyo release via EurekAlert, Nov. 10, 2026; the study in Nature, “Wafer-scale epitaxy growth of high-mobility p-type boron carbon nitride”.