Phosphorus semiconductor overcomes resistance

Two-dimensional semiconductors, such as graphene and transition metal dichalcogenides, are expected to drive the miniaturization of electronic devices by providing ultrathin active channels for charge-carrier transport in field effect transistors (FETs).

FETs influence the flow of current through their channels by applied voltage and behave like electronically controlled switches or amplifiers. Electric resistance arises at the interfaces between the semiconductor channels and metal electrodes, limiting the charge injection into the devices and preventing FETs from reaching their full potential.

“Reducing this contact resistance will improve the current delivery capability and improve the performance of the FETs, which will pave the way for future microelectronics,” said Shubham Tyagi, a Ph.D. student in Udo Schwingenschlögl’s group at KAUST (King Abdullah University of Science and Technology) in Saudi Arabia.

Now, Schwingenschlögl’s team has designed a junction-free FET using two-dimensional blue phosphorene as the single electroactive material. Blue phosphorene is a semiconductor but becomes a metal when stacked into a bilayer.