Patterning RGB Perovskite Pixels via Sequential Vapor-Solution Process for Integrated Wavelength-Selective...

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Patterning multi-wavelength pixel arrays is challenging due to solvent-based method limitations like degradation and contamination.
• Halide perovskites offer potential for next-generation optoelectronics due to their optical and electronic properties, but require precise patterning.

Purpose of the Study:

• To develop a precise, damage-free patterning strategy for halide perovskite pixel arrays.
• To enable tunable bandgaps for multi-wavelength optoelectronic applications.

Main Methods:

• A two-step hybrid patterning strategy combining vapor-deposited lead halides (PbX2) with solution-processed methylammonium halides (MAX).
• Fabrication of RGB perovskite pixel arrays with controlled bandgaps (1.77–2.48 eV).

Main Results:

• Achieved precise control over MAPbX3 bandgaps without structural damage or contamination.
• Produced RGB perovskite pixel arrays with sharp edges, uniform thickness (~220 nm), and high crystallinity.
• Demonstrated wavelength-selective photodetectors (PDs) with peak external quantum efficiencies of 65% (658 nm), 61% (520 nm), and 50% (450 nm).
• Successfully performed direct RGB imaging with a 5x5 image sensor array, validating intrinsic pixel wavelength selectivity.

Conclusions:

• The scalable hybrid patterning strategy enables precise fabrication of multi-wavelength perovskite pixel arrays.
• This versatile platform supports advanced optoelectronic applications, including color-resolved PDs, integrated image sensors, and neuromorphic vision systems.