Effect of Exchange-Correlation Functionals on Schottky Barriers at Si/Metal Interfaces

Area of Science:

• Computational materials science
• Condensed matter physics
• Semiconductor device physics

Background:

• Accurate Schottky barrier height (SBH) prediction is vital for electronic and optoelectronic devices.
• First-principles calculations face challenges like bandgap underestimation and interface alignment.

Purpose of the Study:

• To systematically assess computational strategies for SBH prediction.
• To identify key factors influencing SBH accuracy at metal-semiconductor interfaces.
• To benchmark different theoretical approaches using Si(111)/metal interfaces.

Main Methods:

• Evaluation of various exchange-correlation functionals.
• Comparison of three bulk reference protocols (relaxed, relaxed with spin-orbit coupling, strained).
• Assessment of structural and electrostatic consistency between interface and bulk calculations.

Main Results:

• Structural and electrostatic consistency between interface and bulk calculations is the dominant factor for SBH accuracy.
• Mixed hybrid-semilocal functionals combined with strained reference protocols significantly improve SBH predictions.
• Achieved near-experimental accuracy for SBHs with favorable computational cost.

Conclusions:

• Optimized computational strategies, focusing on interface-bulk consistency, are essential for accurate SBH prediction.
• The proposed approach offers a reliable and efficient method for designing semiconductor devices.
• This work provides a physically grounded framework for advancing metal-semiconductor interface studies.