Applied Surface Science ( IF 6.182 ) Pub Date : 2020-01-12 , DOI: 10.1016/j.apsusc.2020.145351 A. Stanculescu; C. Breazu; M. Socol; O. Rasoga; N. Preda; G. Petre; A.M. Solonaru; M. Grigoras; F. Stanculescu; G. Socol; G. Popescu-Pelin; M. Girtan
This paper presents some studies on the organic heterostructures realized by Matrix Assisted Pulsed Laser Evaporation in both bi-layer and mixed layer configurations on glass substrates covered by flat or nano-patterned ITO. The donor, a star-shaped arylenevinylene compound, 4,4́,4́́-tris[(4́-diphenylamino) styryl] triphenylamine, and acceptor, a non-fullerene compound, N,Ń-bis-(1-dodecyl)perylene-3,4,9,10 tetracarboxylic diimide, were blended in three weight ratio: 1:2, 1:3 and 1:4.
A grating of cylindrical pillars with a periodicity of 1.1 μm has been developed by UV-Nanoimprint Lithography in a polymer layer. The shape of the nanostructures changed to cone trunk by the Pulsed Laser Deposition of ITO on this nanostructured surface.
The effect of the nanostructures and composition on the optical and electrical properties of the heterostructures was analyzed.
The nano-patterning affected both the UV-Vis transmission and photoluminescence through the multiple reflections inside the cavities and at interfaces and the particularities of the molecular arrangement. The patterning was preserved independently of composition, but the roughness increased with increasing acceptor amount.
The I-V characteristics drawn at room temperature in dark revealed an ohmic contact behavior for all heterostructures. The nano-patterning had a similar effect on the current in the heterostructures with mixed layer (1:2) and stacked bi-layer.