Tuneable 2D surface Bismuth incorporation on InAs nanosheets

Area of Science:

• Materials Science
• Surface Science
• Nanotechnology

Background:

• Chemical bonding at semiconductor-metal interfaces dictates electronic and optical properties.
• Controlling interface bonding is crucial for advanced nanostructure applications.

Purpose of the Study:

• Investigate bismuth (Bi) adsorption and incorporation on 2D wurtzite indium arsenide (InAs) (112̄0) nanosheets.
• Explore temperature-dependent control over Bi bonding configurations.
• Compare adsorption on wurtzite InAs nanosheets with zinc blende InAs (110) surfaces.

Main Methods:

• Experimental investigation of Bi adsorption on InAs nanosheets.
• Temperature-controlled deposition of Bi.
• Ab initio theoretical modeling to confirm adsorption and analyze energetics.
• Comparison of adsorption rates on InAs and silicon (Si) substrates.

Main Results:

• Achieved temperature-controlled Bi incorporation (anionic- or cationic-like bonding) on wurtzite InAs (112̄0) nanosheets between room temperature and 400 °C.
• Observed significant differences in Bi adsorption and incorporation between wurtzite InAs nanosheets and zinc blende InAs (110) surfaces, despite similar nearest neighbor configurations.
• Theoretical modeling confirmed experimental adsorption results and highlighted the roles of formation energies and kinetic barriers.
• Demonstrated a >2.5 times difference in Bi adsorption rates between the two InAs surfaces, with negligible adsorption on Si substrates.

Conclusions:

• Geometric differences in crystal structures significantly influence adsorption and incorporation behavior.
• Temperature-controlled Bi incorporation offers a pathway for tuneable integration into 2D InAs nanostructures.
• The findings present opportunities for fabricating novel 2D InAs nanostructures with tailored interfaces on standard Si substrates.