title: Monolithic and Flexible ZnS/SnO2Ultraviolet Photodetectors with Lateral Graphene Electrodes.
abstract: A continuing trend of miniaturized and flexible electronics/optoelectronic calls for novel device architectures made by compatible fabrication techniques. However, traditional layer-to-layer structures cannot satisfy such a need. Herein, a novel monolithic optoelectronic device fabricated by a mask-free laser direct writing method is demonstrated in which in situ laser induced graphene-like materials are employed as lateral electrodes for flexible ZnS/SnO2ultraviolet photodetectors. Specifically, a ZnS/SnO2thin film comprised of heterogeneous ZnS/SnO2nanoparticles is first coated on polyimide (PI) sheets by a solution process. Then, CO2laser irradiation ablates designed areas of the ZnS/SnO2thin film and converts the underneath PI into highly conductive graphene as the lateral electrodes for the monolithic photodetectors. This in situ growth method provides good interfaces between the graphene electrodes and the semiconducting ZnS/SnO2resulting in high optoelectronic performance. The lateral electrode structure reduces total thickness of the devices, thus minimizing the strain and improving flexibility of the photodetectors. The demonstrated lithography-free monolithic fabrication is a simple and cost-effective method, showing a great potential for developement into roll-to-roll manufacturing of flexible electronics.
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of Missouri, Columbia, MO, 65211, USA.
authors.forename: Cheng
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of Missouri, Columbia, MO, 65211, USA.
authors.forename: Yunchao
authors.initials: Y
authors.lastname: Xie
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of Missouri, Columbia, MO, 65211, USA.
authors.forename: Heng
authors.initials: H
authors.lastname: Deng
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of Missouri, Columbia, MO, 65211, USA.
authors.forename: Travis
authors.initials: T
authors.lastname: Tumlin
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of Missouri, Columbia, MO, 65211, USA.
authors.forename: Chi
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of Missouri, Columbia, MO, 65211, USA.
authors.forename: Jheng-Wun
authors.initials: JW
authors.lastname: Su
authors.affiliation: Department of Physics and Astronomy, University of Missouri, Columbia, MO, 65211, USA.
authors.forename: Ping
authors.initials: P
authors.lastname: Yu
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of Missouri, Columbia, MO, 65211, USA.
authors.forename: Jian
authors.initials: J
authors.lastname: Lin
keywords: UV photodetector; ZnS/SnO2 nanoparticles; laser-induced graphene; lateral electrodes; monolithic