Epigraphene-based heterostructures for novel electronics – Epinel

The recent discovery of high-mobility semiconducting epigraphene (SEG)—exceeding silicon’s mobility by a factor of ten—grown on macroscopic terraces of silicon carbide (SiC), has opened the door to a new 2D electronics platform fully compatible with existing microelectronics processing. SEG overcomes graphene’s long-standing limitation: the absence of a bandgap. It thus offers a viable route to 2D semiconductors for nanoelectronics, enabling ultra-low-power tunneling field-effect transistors (TFETs), THz operation, device miniaturization, and electrostatic top-gate doping.
A unique feature of SEG is its ability to be intercalated with a wide range of materials—from molecules to metals and semiconductors—creating novel, air-stable 2D systems and enabling heterostructure engineering. For example, hydrogen intercalation transforms SEG into quasi-free-standing graphene, while gold intercalation results in a 2D semiconductor.
This project aims to develop SEG-based TFETs with short channels and subthreshold slopes below 60 mV/decade, benchmark their performance, and investigate hydrogen-intercalated SEG as a seamless interconnect. We will explore SEG heterostructures, beginning with hydrogen intercalation and focusing on ballistic edge-state conduction over tens of microns. Low-temperature coherence measurements will probe the still poorly understood nature of these edge states, which may open the door to coherent electronics. Finally, metal-intercalated SEG will be explored as a platform for air-stable, low-resistance graphene contacts and for studying novel 2D properties—including moiré effects and unconventional interface phenomena.