A research team from the South Korean Institute for Basic Science (IBS) has developed a new method for growing 1D metallic materials less than 1 nm wide. They applied this technique to create a new structure for 2D semiconductor logic circuits, using the 1D metals as gate electrodes in very small transistors. However, creating very small transistors that can control electron movement within a few nanometers has been challenging. The size of semiconductor devices depends on the width and efficiency of the gate electrode. Current manufacturing processes can't make gate lengths below a few nanometers due to limitations in lithography. To address this, the team used the mirror twin boundary (MTB) of molybdenum disulfide, which is a 1D metal only 0.4 nm wide, as a gate electrode. The IBS team achieved the 1D MTB metallic phase by altering the crystal structure of a 2D semiconductor at the atomic level.

The International Roadmap for Devices and Systems (IRDS) predicts semiconductor technology to reach about 0.5 nm by 2037, with transistor gate lengths of 12 nm. The research team's transistor demonstrated a channel width as small as 3.9 nm, surpassing this prediction. The 1D MTB-based transistor also offers advantages in circuit performance. Unlike some current technologies (FinFETs or GAA) that face issues with parasitic capacitance in highly integrated circuits, this new transistor can minimize such problems due to its simple structure and narrow gate width.