Researchers grew a single layer of boron carbon nitride across a wafer and used it to build p-type transistors, which carry charge through electron vacancies called holes. The material addresses a missing counterpart to electron-carrying two-dimensional semiconductors. The demonstration brings larger-area fabrication together with useful electrical properties, at the laboratory stage of device development.
Researchers have grown wafer-scale boron carbon nitride and used the single-layer material in p-type transistors. These devices carry charge through holes, the vacancies left by electrons. High-performance hole-carrying materials have been a difficult counterpart to the electron-carrying semiconductors needed for complementary two-dimensional circuits.[1], [2]
The team combined two chemical precursors to control when boron, carbon and nitrogen reached the growing surface. Simulations guided the chemical vapour deposition process. Microscopy and spectroscopy then examined the resulting lattice, in which carbon atoms replace atoms within boron nitride rather than forming separate graphene regions. The researchers grew the film across a 2-inch wafer and measured a thickness of about 0.5 nanometres.[1]
Transistors made from the material showed hole mobility of about 100 square centimetres per volt-second and an on-to-off current ratio of 100,000,000. Measurements also found a 1.90-electronvolt bandgap, consistent with a semiconductor that can switch current. The authors link these properties to carbon incorporated into the lattice. Their devices establish a possible p-type component for future complementary electronics; combining it with electron-carrying materials remains an integration goal.[1]
