title: Alternative Patterning Process for Realization of Large-Area, Full-Color, Active Quantum Dot Display.
abstract: Although various colloidal quantum dot (QD) coating and patterning techniques have been developed to meet the demands in optoelectronic applications over the past years, each of the previously demonstrated methods has one or more limitations and trade-offs in forming multicolor, high-resolution, or large-area patterns of QDs. In this study, we present an alternative QD patterning technique using conventional photolithography combined with charge-assisted layer-by-layer (LbL) assembly to solve the trade-offs of the traditional patterning processes. From our demonstrations, we show repeatable QD patterning process that allows multicolor QD patterns in both large-area and microscale. Also, we show that the QD patterns are robust against additional photolithography processes and that the thickness of the QD patterns can be controlled at each position. To validate that this process can be applied to actual device applications as an active material, we have fabricated inverted, differently colored, active QD light-emitting device (QD-LED) on a pixelated substrate, which achieved maximum electroluminescence intensity of 23 770 cd/m2, and discussed the results. From our findings, we believe that our process provides a solution to achieving both high-resolution and large-scale QD pattern applicable to not only display, but also to practical photonic device research and development.
authors.forename: Joon-Suh
authors.initials: JS
authors.lastname: Park
authors.forename: Jihoon
authors.initials: J
authors.lastname: Kyhm
authors.affiliation: Department of Materials Science and Engineering, Yonsei University , Seoul 03722, Korea.
authors.forename: Hong Hee
authors.initials: HH
authors.lastname: Kim
authors.affiliation: School of Electrical Engineering, Korea University , Seoul 02841, Korea.
authors.forename: Shinyoung
authors.initials: S
authors.lastname: Jeong
authors.forename: JoonHyun
authors.initials: J
authors.lastname: Kang
authors.affiliation: School of Electrical Engineering, Korea University , Seoul 02841, Korea.
authors.forename: Song-Ee
authors.initials: SE
authors.lastname: Lee
authors.forename: Kyu-Tae
authors.initials: KT
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, Korea University , Seoul 02841, Korea.
authors.forename: Kisun
authors.initials: K
authors.lastname: Park
authors.forename: Nilesh
authors.initials: N
authors.lastname: Barange
authors.forename: JiYeong
authors.initials: J
authors.lastname: Han
authors.forename: Jin Dong
authors.initials: JD
authors.lastname: Song
authors.forename: Won Kook
authors.initials: WK
authors.lastname: Choi
authors.forename: Il Ki
authors.initials: IK
authors.lastname: Han
keywords: Colloidal quantum dots; light-emitting device; patterning; photolithography