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Electrically conductive polymer materials are increasingly being used as electronic materials, for example, in thin-film transistors. However, the low mobility of charge carriers limits their use. One of the ways to increase the mobility of charge carriers can be the use of interface conductivity along the regions separating the two polymer films. It is important that it could be realized with non-conjugated polymers. There is no direct experimental evidence that the transport of charge carriers occurs along such an interface. It is impossible to deny the possibility of transport on the surfaces of polymer films. The purpose of this work is to study the current flow path in a multilayer sample by marking the polymer–polymer interface with a doping nanolayer of a Cu2O island film. Spectral methods in the field of electronic absorption of copper oxide were used to control the island film. The electronic parameters of the polymer–polymer interface were studied using injection methods and volt-ampere characteristics. Atomic force microscopy was used to control the thickness and uniformity of the samples. It was found that the doping of the polymer–polymer interface using Cu2O particles strongly affects the transport of charge carriers; in particular, the conductivity of the structure increases. It is established that this is due to an increase in the mobility of the charge carriers and a decrease in the height of the potential barrier at the 3D metal–2D interface area. Thus, it is established that the transport of charge carriers occurs along the polymer–polymer interface at the structure parameters specified in this work.

This paper presents the results of an experimental investigation of the supramolecular structure of polydiphenylenephthalide thin films that exhibit effects of resistive switching. The supramolecular structure of the polymer has been investigated using small-angle neutron scattering in conjunction with atomic force microscopy. It has been found that the internal structure of polymer films consists of structural elements in the form of spheroids. The sizes of the structural elements, which were obtained from the neutron scattering data and analysis of the atomic force microscopy images, correlate well with each other. A model of the formation of polymer layers has been proposed. The observed structural elements in polymer films are formed due to the association of macromolecules in the initial polymer solution.

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The mechanism of charge carrier transport in the indium tin oxide (ITO)/polymer/Cu structure is studied, where thin films of copoly(arylene ether ketone) with cardo fluorene moieties are used. This copoly(arylene ether ketone) is non-conjugated polymer which has the properties of electronic switching from the insulating to the highly conductive state. The dependence on the polymer film thickness of such parameters as the potential barrier at the ITO/polymer interface, the concentration of charge carriers, and their mobility in the polymer is studied for the first time. The study of this system is of interest due to the proven potential of using the synthesized polymer in the contact system of a silicon solar cell with an ITO top layer. The parameters of charge carriers and ITO/polymer barrier are evaluated based on the analysis of current–voltage characteristics of ITO/polymer/Cu structure within the injection current models and the Schottky model. The thickness of the polymer layer varies from 50 nm to 2.1 µm. The concentration of intrinsic charge carriers increases when decreasing the polymer film thickness. The charge carrier mobility depends irregularly on the thickness, showing a maximum of 9.3 × 10−4 cm2/V s at 210 nm and a minimum of 4.7 × 10−11 cm2/V s at 50 nm. The conductivity of polymer films first increases with a decrease in thickness from 2.1 µm to 210 nm, but then begins to decrease upon transition to the globular structure of the films at smaller thicknesses. The dependence of the barrier height on polymer thickness has a minimum of 0.28 eV for films 100–210 nm thick. The influence of the supramolecular structure and surface charge field of thin polymer films on the transport of charge carriers is discussed.

This paper investigates the dependence of the potential barrier at the metal/polymer interface on the elastic and plastic deformation of the metal. Interest in such studies is observed due to the fact that flexible electronic devices are being developed on the basis of organic materials, which should provide the same efficiency and stability as their rigid counterparts. At the same time, it is known that deformation processes in the metal/polymer structure can lead to changes in the electrophysical parameters of such a structure. The observed effect can be used to control the state of metal structures and samples, such as phase transitions, crack initiation, and structural changes. Developments in the field of small strain sensorics and the development of micromechanical devices are being actively pursued. In this regard, the search becomes more urgent for organic materials with a complex of physical properties, improved mechanical characteristics, acceptable film-forming properties and required electrical characteristics. The energy barrier at the metal/polymer interface is well defined within the Schottky theory. The transport of charge carriers is described by the injection model. However, in contrast to the classical metal/semiconductor transition, the potential barrier of such an interface is determined not by the difference between the metal work function and the electron affinity energy of the polymer, but by the difference between the metal and polymer work functions. The electronic work function from metal and polymer can be chosen so that the difference between them is small. Consequently, small changes in the work function of an electron from a metal will lead to a noticeable change in the value of the potential barrier. In addition, the effects of switching from a dielectric to a state with high conductivity observed in some polymers of polyarylenephthalides make it also possible to determine abrupt and discontinuous changes that occur in a metal sample. It was found that with an increase in the degree of elastic deformation of the metal, the value of the potential barrier decreases. During the transition from elastic to plastic deformation of the metal, a transition of the dielectric polymer film is observed to a state with high conductivity. The results of this paper can be used for nondestructive testing and analysis of the state of metals.