Defects in 2D Materials

This lecture covers the most common defect types in 2D materials, including point defects like vacancies and substitutions, as well as line defects such as grain boundaries and lateral heterostructures. The influence of these defects on field-effect transistor characteristics is discussed, along with strategies to avoid grain boundaries. The lecture also delves into the quantum capacitance of 2D semiconductors and the impact of a dielectric environment on electrical transport. Various methods for defect healing, such as chemical treatments with thiols and TFSI superacid, are explored, highlighting their positive effects on reducing contact resistance and enabling single-photon sources.

About this result

This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.

Related lectures (33)

Related concepts (37)

Crystallographic defect

A crystallographic defect is an interruption of the regular patterns of arrangement of atoms or molecules in crystalline solids. The positions and orientations of particles, which are repeating at fixed distances determined by the unit cell parameters in crystals, exhibit a periodic crystal structure, but this is usually imperfect. Several types of defects are often characterized: point defects, line defects, planar defects, bulk defects. Topological homotopy establishes a mathematical method of characterization.

Semiconductor

A semiconductor is a material which has an electrical conductivity value falling between that of a conductor, such as copper, and an insulator, such as glass. Its resistivity falls as its temperature rises; metals behave in the opposite way. Its conducting properties may be altered in useful ways by introducing impurities ("doping") into the crystal structure. When two differently doped regions exist in the same crystal, a semiconductor junction is created.

Transistor

A transistor is a semiconductor device used to amplify or switch electrical signals and power. It is one of the basic building blocks of modern electronics. It is composed of semiconductor material, usually with at least three terminals for connection to an electronic circuit. A voltage or current applied to one pair of the transistor's terminals controls the current through another pair of terminals. Because the controlled (output) power can be higher than the controlling (input) power, a transistor can amplify a signal.

Dielectric loss

In electrical engineering, dielectric loss quantifies a dielectric material's inherent dissipation of electromagnetic energy (e.g. heat). It can be parameterized in terms of either the loss angle δ or the corresponding loss tangent tan(δ). Both refer to the phasor in the complex plane whose real and imaginary parts are the resistive (lossy) component of an electromagnetic field and its reactive (lossless) counterpart.

Relative permittivity

The relative permittivity (in older texts, dielectric constant) is the permittivity of a material expressed as a ratio with the electric permittivity of a vacuum. A dielectric is an insulating material, and the dielectric constant of an insulator measures the ability of the insulator to store electric energy in an electrical field. Permittivity is a material's property that affects the Coulomb force between two point charges in the material. Relative permittivity is the factor by which the electric field between the charges is decreased relative to vacuum.

EE-567: Semiconductor devices II

Students will learn about understanding the fundamentals and applications of emerging nanoscale devices, materials and concepts. Remark: at least 5 students should be enrolled for the course to be g

Defects in 2D Materials EE-567: Semiconductor devices II

Delves into common defects in 2D materials, their impact on transistor characteristics, formation energy, transport behavior, and van der Waals epitaxy.

Semiconductor Devices II: Defects Engineering EE-567: Semiconductor devices II

Covers the analysis of measurements and defects engineering in semiconductor devices, including density of states and defect probing.

Defects in 2D Materials EE-567: Semiconductor devices II

Explores common defects in 2D materials, their impact, mitigation strategies, and positive applications.

Semiconductor Devices II: Contact Resistance Modeling EE-567: Semiconductor devices II

Explores contact resistance modeling in semiconductor devices, focusing on gate voltage calculation and defect analysis.

Simulation of 2D Field Effect Transistors EE-567: Semiconductor devices II

Covers the simulation of 2D Field Effect Transistors and the advantages of using Green's Function.