ИСТИНА

The intensive development of the technology of manufacturing miniature electronic devices requires the creation of miniature power sources and energy storage devices for them. In these theses we report new class of an ultrathin batteries based on a films consisting of silicon nanoparticles (nc-Si film) and bounded by two flat metal electrodes with the upper electrode being nanoporous and capable of passing the molecules of water and oxygen. The total thickness of such a battery is 2 μm, which makes it an ideal candidate (using a flexible substrate) as a flexible power source, which for example can be embedded in electronic paper or used in next-generation smart cards. Also, such sources can be organized directly on the surface of silicon chips. The value of the detected electro-motion force (EMF) depends on the temperature of the sample, as well as on the humidity of atmosphere surrounding the sample and on the presence of oxygen in it, but the main factor leading to generation of the EMF in sample is the presence of the water vapor in the environment. The maximum emf value obtained in the nc-Si thin-film structure was 1.5V. The power released by the structure to an external matched load in the temperature range from 20 to 150° C reaches values 10-2 to 5∙10-1 W/g. In the model, it is assumed that in the sample simultaneously with the spontaneously generated EMF(ε), there is some parallel process of transport of electric charges, which shunts it. We propose that shunting resistance is largely independent of temperature in the studied temperature interval and the series resistance with EMF is of activational character. From the analysis of the process of generation of EMF by the structures into which a Nafion membrane was introduced, and also from the analysis of impedance spectra, it was established that the main role in the separation of charges inside the structure is determined by ion transport, namely by the proton conductivity. We propose that EMF generation in Al/nc-Si/M structures is initiated by diffusion of water vapor through porous contact leading to oxidation of nc-Si and the diffusion of H+ ions from top electrode to the bottom one. This work was supported by Russian Foundation for Basic Research grant № 15-02-09135.