Role of Evaporated Silver Nanoparticles in Organic Field-Effect Transistor: Electrical Effects and Dependence on the Size

The electrical effects of metal nanoparticles are deterniiiied by the nature of a single nanoparticle (shape, size, surface) and their correlation with the nanoscale electronic structure. In this work, we report that electrical propertieS of evaporated silver nanoparticles can be controlled by different thicknesses and thermal annealing times. The particle -size and size distribution were :first fully characterized by the AFM and optical extinction spectra, and then their electrical properties such as current trapping and threshold Voltage were studied by the organiC field-effect 'transistor with a device structure of Si/SiO2-/Ag-NPs/PMMA/PTB7/Ag: The- results show that the thlekness, decrease and thermal annealing are effective ways for a -lower charge trapping, which corresponds to smaller particle size and homogeneous particle distribution without particle aggregates. These results would be helpful for the optoelectronic applications of metal nanoparticles: