High-Resolution In Situ Crystallization and Patterning of a CsPbBr3 Film via Femtosecond Laser Printing

Establishinghigh-precision patterning technology forhigh-qualityperovskite films is critical for practical applications requiringoptoelectronic device arrays. Here, we report a femtosecond laserprinting strategy to realize high-precision and high-quality patternedperovskite films by integrating in situ crystallization and patterningin one printing step. Compared with a thermal-annealed CsPbBr3 film, the crystallization quality of a laser-printed filmhas been improved because of localized nucleation and growth at thelaser-irradiated area, avoiding the incomplete film coverage and poorcrystallization quality due to rapid solvent evaporation in the largearea during the thermal annealing process. Also, high-resolution pixelarrays and designed patterns with a minimum line width of 2 & mu;mhave been demonstrated by means of the high precision of femtosecondlaser printing. More importantly, we have fabricated a prototype ofperovskite light-emitting diodes (LEDs) demonstrating the potentialof femtosecond laser printing technology for the fabrication of high-precisionpatterned perovskite film optoelectronic devices for display application.