Vacuum-deposited diphenyl-diketo-pyrrolopyrroles structures with photoelectrical applications

18th International Summer School on Vacuum, Electron and Ion Technologies

Georgiev, Y.^1,3 ; Zhivkov, I.^1,2 ; Takov, T.^3 ; Angelov, G.^3 ; Prikryl, R.^1 ; Stritesky, S.^1 ; Honova, J.^1 ; Weiter, M.^1

Faculty of Chemistry, Center for Materials Research, Brno University of Technology, 118 Purkynova, 612 00 Brno, Czech Republic^1

Acad. J. Malinowski Institute of Optical Materials and Technologies, Bulgarian Academy of Sciences, Acad. G. Bonchev str., Bl. 101/109, 1113 Sofia, Bulgaria^2

Faculty of Electronic Engineering and Technologies, Department of Microelectronics, Technical University of Sofia, 8 Kl. Ochridski Blvd., 1756 Sofia, Bulgaria^3

关键词: Film homogeneity;    Low-molecular-weight materials;    Multilayer structures;    Organic/inorganic;    Photo-electrical properties;    Physical vacuum depositions;    Spherical structures;    Thickness uniformity;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/514/1/012005/pdf
DOI  :  10.1088/1742-6596/514/1/012005

来源: IOP

【 摘 要 】

Modern organic semiconductor devices are designed as stacked organic/inorganic thin films. In such multilayer structures, strong requirements are set forth to the properties of the specific films, e.g., film homogeneity, thickness uniformity and roughness. The physical vacuum deposition (PVD) technique fulfils all of these requirements having even the capability of producing the whole multilayer structure in the same vacuum cycle. Diphenyl-diketo-pyrrolopyrroles (DPP) are low-molecular-weight materials with promising luminescence and photoelectrical properties. This study deals with PVD of thin DPP films and measurement of their properties. The organic films and inorganic electrodes of the multilayer structures were prepared in the same vacuum cycle, and then the structures were encapsulated in a glove box avoiding exposure to oxygen. ITO|composite|Al structures were prepared with active DPP-C60composite films (ratio 60:40 mass %) of about 100 nm thicknesses. The surface morphology of the films was studied by SEM imaging, which revealed uniform films containing separate spherical structures. The dark current and the photoconductivity were measured and the photoelectrical behavior of the structures was estimated. It was found that the optimized preparation of the structures under the aforementioned conditions leads to an improvement of their photoelectrical properties.