Direct Patterning of CsPbBr₃ Nanocrystals via Electron-Beam Lithography

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Lead-halide perovskite (LHP) nanocrystals offer tunable band gaps, strong absorption, and high photoluminescence quantum yield (PLQY).
• Their properties make them promising for optoelectronic applications.
• Patterning active materials enhances tunability and functionality for intricate device designs.

Purpose of the Study:

• To develop a method for patterning colloidal LHP nanocrystals at the nanoscale.
• To explore the feasibility of using electron-beam lithography (EBL) for LHP nanocrystal patterning.
• To create intricate LHP nanocrystal designs for potential device fabrication.

Main Methods:

• Adapted a patterning technique originally developed for II-VI quantum dots.
• Utilized electron-beam lithography (EBL) to pattern colloidal LHP nanocrystals.
• Employed ligand cross-linking as the primary mechanism for nanocrystal assembly and pattern formation.

Main Results:

• Successfully created patterns of LHP nanocrystals ranging from 100s of nanometers to several microns.
• Demonstrated the formation of intricate designs using the developed patterning technique.
• Observed a slight decrease in luminescent properties after EBL exposure, but the patterned structures remained emissive.

Conclusions:

• Electron-beam lithography (EBL) is a viable method for patterning lead-halide perovskite (LHP) nanocrystals.
• Ligand cross-linking effectively binds nanocrystals into desired patterns.
• This work represents a significant step towards nanoscale patterning of LHP nanocrystals for advanced device applications.