Extended Hückel Semi-Empirical Approach as an Efficient Method for Structural Defects Analysis in 4H-SiC

Area of Science:

• Materials Science
• Semiconductor Physics
• Computational Chemistry

Background:

• 4H-Silicon Carbide (4H-SiC) is a crucial semiconductor material with diverse applications.
• Understanding the impact of structural defects on electronic properties is vital for device performance.
• Existing methods for simulating defects can be computationally intensive.

Purpose of the Study:

• To develop and present an efficient computational method for analyzing structural defects in 4H-SiC.
• To investigate the influence of vacancies, stacking faults, and dislocations on 4H-SiC's energy levels and band gap.
• To provide a faster alternative to standard Density Functional Theory (DFT) methods for defect simulation.

Main Methods:

• Application of the semi-empirical extended Hückel method.
• Simulation of ideal 4H-SiC and structures with various defects (vacancies, stacking faults, threading edge dislocations).
• Utilizing the Synopsys QuatumATK package for computational modeling.

Main Results:

• The extended Hückel method accurately predicts the influence of structural defects on 4H-SiC energy levels and band gap.
• Simulations show good agreement with established DFT methods.
• Significant reduction in computational time compared to DFT, enabling modeling of ~1000 atom structures within hours.

Conclusions:

• The presented semi-empirical method offers a fast and accurate approach for simulating non-ideal 4H-SiC structures.
• This method facilitates efficient analysis of defect-related electronic property changes in 4H-SiC.
• Enables rapid exploration of material properties for optimizing semiconductor device design.