High Electron Mobility in Si-Doped Two-Dimensional β-Ga₂O₃ Tuned Using Biaxial Strain

Area of Science:

• Materials Science
• Condensed Matter Physics
• Semiconductor Physics

Background:

• Two-dimensional (2D) semiconductors are crucial for flexible electronics and optoelectronics.
• Poor electron mobility in conventional 2D materials limits their application scope.
• Developing high-performance 2D materials is essential for advancing electronic devices.

Purpose of the Study:

• To investigate the effects of biaxial strain on Si-doped 2D β-Ga₂O₃.
• To determine the structural stability and electronic properties of the modified material.
• To explore the potential of Si-doped 2D β-Ga₂O₃ for nanoscale electronics.

Main Methods:

• First-principles calculations combined with Boltzmann transport theory.
• Assessment of structural stabilities using formation energy, phonon spectrum, and ab initio molecular dynamics.
• Analysis of band gap, band structure transitions, and electron mobility under varying strain.

Main Results:

• Si-doped 2D β-Ga₂O₃ exhibits tunable band gaps from 2.46 eV to 1.38 eV with biaxial strain.
• Tensile strain induces a direct-to-indirect band gap transition.
• Electron mobility significantly increases to 4911.18 cm² V^-1 s^-1 at 8% tensile strain due to reduced quantum confinement.
• Electrical conductivity improves with tensile strain and elevated temperatures (300 K–800 K).

Conclusions:

• Biaxial strain effectively tunes the electronic properties of Si-doped 2D β-Ga₂O₃.
• The material shows great potential for high-performance flexible nanoelectronic devices.
• Strain engineering offers a viable pathway to optimize 2D semiconductor performance.