Epitaxy Beyond Periodic Lattices: Interfacial Modulation Enabled by Defect State 2D Materials

Area of Science:

• Materials Science
• Condensed Matter Physics
• Surface Science

Background:

• Remote epitaxy (RE) is a method for growing single-crystal films on 2D materials (2DMs).
• RE is vital for heterogeneous integration of materials and devices.
• The influence of 2DM structural characteristics on RE is not well understood.

Purpose of the Study:

• To investigate the impact of defects in 2DMs on remote epitaxy.
• To explore the underlying mechanism of defect-mediated RE.
• To assess the potential applications of defect-engineered RE.

Main Methods:

• Experimental synthesis and characterization of defective hexagonal boron nitride (h-BN).
• Theoretical modeling and simulations to understand interfacial interactions.
• Fabrication and testing of heterojunction detectors.

Main Results:

• Remote epitaxy was achieved on defective h-BN (DBN), but not on pristine h-BN.
• A defect-induced charge transfer enhancement (DCTE) effect was identified in DBN.
• DCTE enhances electron delocalization and interfacial charge transfer, enabling RE beyond lattice-matching constraints.
• The DCTE effect was confirmed in other remote epitaxial structures.
• DBN/GaN heterojunction detectors showed improved detection sensitivity.

Conclusions:

• 2D lattice defects critically impact remote epitaxy by enabling enhanced interfacial coupling via DCTE.
• This finding expands the understanding of RE mechanisms and interface coupling.
• The DCTE effect offers a new pathway for multi-dimensional material integration and improved device performance.