Interfacial effects on leakage currents in Cu/α-cristobalite/Cu junctions

Area of Science:

• Materials Science
• Condensed Matter Physics
• Semiconductor Device Physics

Background:

• Miniaturization of integrated circuits increases leakage currents in dielectric films.
• Quantum transport at interconnect-dielectric interfaces is crucial but understudied.
• First-principles investigations are needed to understand interfacial effects on leakage.

Purpose of the Study:

• To investigate interfacial-dependent leakage currents in Cu/α-cristobalite/Cu junctions.
• To explore quantum transport phenomena at these critical interfaces.
• To determine the impact of interface composition on electrical properties.

Main Methods:

• First-principles calculations.
• Density functional theory (DFT).
• Non-equilibrium Green's function (NEGF) formalism.

Main Results:

• Oxygen-rich interfaces exhibit the lowest leakage currents under small bias.
• Silicon-rich and oxygen-poor interfaces show higher leakage.
• Oxygen-poor interfaces possess a wider transmission gap, suggesting potentially better dielectric strength.

Conclusions:

• Interface composition significantly influences leakage currents in dielectric films.
• Oxygen-rich interfaces are optimal for reducing leakage.
• Oxygen-poor interfaces may offer enhanced dielectric properties despite higher leakage.