Rapid 2D Patterning of High‐Performance Perovskites Using Large Area Flexography

Abstract

Solution processing of metal halide perovskites offers the potential for efficient, high‐speed roll‐based manufacturing of emerging optoelectronic devices such as lightweight photovoltaics and light emitting diodes at lower cost than achievable with incumbent technologies (e.g., Silicon). However, current perovskite fabrication methods are limited in their speed, uniformity, and patterning resolution, relying on subtractive postdeposition scribing for integration of modules and device arrays. Here, a method for flexographic printing of MA0.6FA0.4PbI3 at 60 m min−1, the fastest reported perovskite absorber deposition and the first report of inline drying integrated with roll‐based printing, is presented. This process delivers high‐resolution patterning (< 3 µm line edge roughness) and precise thickness control through rheological design of precursor inks, allowing scalably printed 50 µm features over large areas (140 cm2), while obviating damaging scribing steps. 2D scanning photoluminescence (PL) is applied to resolve correlations between ink leveling dynamics and optoelectronic quality. Integrating these highly uniform printed perovskite absorbers into n‐i‐p planar perovskite solar cells, photovoltaic conversion efficiency up to 20.4% (0.134 cm2), the highest performance yet reported for any roll‐printed perovskite cells is achieved. This study, thus, establishes flexography as a scalable approach to deposit precisely‐patterned high‐quality perovskites extensible to applications in emitter and detector arrays.

Patterning of Hybrid Metal Halide Perovskite via Printed Molecular Templates

“…Conversely, in bottom‐up processing, the perovskite is grown into a desired pattern without further interference post crystallization of the film. This has been demonstrated through direct patterning approaches, such as ink‐jet, [ 22 ] gravure, [ 23 ] and flexographic [ 24 ] printing. Alternatively, guided pattern formation was shown by utilizing a template, such as a pre‐patterned substrate, [ 25–27 ] confined channels, [ 28–33 ] or through controlled de‐wetting.…”

Numerical Simulation on Ink Transfer Channel of Flexography Based on Fluid–Solid-Heat Interactions

“…However, with the increasing demand for printing quality and efficiency in the market, further understanding and optimization of the flexographic printing process has become increasingly important [3]. Scholars all over the world have paid much attention to flexographic printing and have deeply studied various aspects of flexographic printing technology [4][5][6][7]. In view of the complexity and difficulty of the printing mechanism of non-absorbent substrates in gravure printing, Wu Shuang, Dong Ling, Guan Xiaomin, and Zhu Hongjuan have made a preliminary study on the transfer and drying of gravure water-based ink [8][9][10][11].…”