Two-dimensional electron or hole gas at ZnO/6H-SiC interface

Abstract

Electronic structures of ZnO(0001)/6H-SiC(0001) interfaces are investigated using first-principles method. Two-dimensional charge carriers are found at the interfaces. Depending on the interface structure, the type of charge carriers can be n-type if oxygen terminated ZnO(0001) is grown on SiC and p-type when the interface is formed with Zn-terminated ZnO and C-terminated SiC. The interface formed with Zn-terminated ZnO and Si-terminated SiC is found to be half-metallic. Intrinsic charge carriers at the interface of the two wide gap semiconductors could be useful for future oxide-based electronics and spintronics.

Low‐dimensional half‐metallic materials: theoretical simulations and design

“…In the interface, electron transfers from LaAlO 3 to a localized interface state formed by Fe 3d orbitals, leading to the Stoner‐type ferromagnetism and spin polarization. Similar results were also found in the ZnO/6H‐SiC interface …”

“…Alternatively, people turn to another feasible route by tuning the existent nonmagnetic nanomaterials into half‐metals. Effective means include applying an electric field, strain engineering, surface adsorption, edge modification, substitutional doping, defect engineering, and interface engineering . Thanks to the discovery of single‐layer graphene and its fascinating properties, a large number of low‐dimensional materials, such as graphitic boron nitride (BN), silicon carbide (SiC), transition metal dichalcogenides, silicene, their nanoribbons, and nanotubes, have emerged .…”

Strain-Induced ZnO Spinterfaces

“…Bulk ferromagnetism has been reported in ZnO doped with Mn, Cu, Co, C, Li, and N and undoped ZnO. − In many cases, ferromagnetism has been attributed to the coupling of unpaired electron spins that was introduced as a result of crystal defects. On the other hand, concomitant advances in the fields of spinterface science and topological insulators have also stirred a flurry of activities in two-dimensional (2D) ferromagnetism and electron gas research. − Magnetic effects at the interface of nonmagnetic oxides as well as ferromagnetism on the surface of hydrogenated-ZnO film have also been reported. , From a broader perspective, these research discoveries bode well for the advent of ground-breaking spintronic semiconductor devices, which endeavor not only to utilize the charge of electrons to process information like traditional electronic devices, but also to take advantage of the spin of electrons, to store information while processing them at the same time. A ferromagnetic semiconductor interface plays an important role in the success of these devices as it improves the efficiency of spin injection across the interface. − …”