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The electron-beam exposure of dielectrics is actively explored in various fields of science. Recently, we have shown the possibility of the selective growth of graphene-like films on oxidized silicon due to an increase in the growth rate of a carbon film on exposed areas. Since the mechanism of the detected phenomenon is unclear, its study is a difficult scientific challenge. In this paper, the potential of atomic-force microscopy as a key instrument for characterization of these films is demonstrated. In particular, the point contact method provides grounds for interpreting processes occurring on the surface in the case of alternating synthesis and exposure to different irradiation doses. This method allows surface topography data and other characteristics ("adhesion" and "gradient" modes) to be obtained in one scan pass. The surface of the graphene-like films is scanned before and after exposure by means of atomic-force microscopy. Analysis of the data obtained shows that the "adhesion" mode enables special features of the samples that are either difficult or impossible to identify in a topographic image to be revealed. The study demonstrates the possibility of obtaining valuable information using cantilever-needle interaction with the surface to measure additional parameters. [ABSTRACT FROM AUTHOR]

For a wide range of practical applications of graphene-like films (GLFs), it is highly desirable to have a material with high uniformity and good electric characteristics. GLFs in this work are defined as graphene films with the crystallite size of several tens of nm. The structure of a CVD-grown GLF is typically disturbed by post-deposition procedures, including transfer and lithography. In this work we aim at the catalyst-free and lithography-free selective deposition procedure, which directly yields the desired GLF pattern on a dielectric substrate, by-passing transfer and lithography, the destructive steps of the manufacturing process. The catalyst-free deposition of graphene-like films can be strongly enhanced by the near-surface electric charge, and in this work we use this effect for selective growth of GLF microstructures. The charge pattern is created by irradiation of the substrate with an e-beam. We study experimental conditions for the selective deposition of GLF from ethanol vapor on SiO2/Si substrate. The e-beam exposure parameters are optimized based on Monte-Carlo simulations and the experimental study of the deposited films Raman spectroscopy and AFM. The electrical properties are studied by the selectively-grown Hall microstructure; it is shown that the film has highly promising characteristics for practical applications. [ABSTRACT FROM AUTHOR]

HTS YBCO films 200–400 nm thick are fabricated by pulsed laser deposition, both without filtration and in the regimes of velocity filtration of particles of an ablation plume. Using AFM and SEM, it is established that the size of large particles in the plane of films during deposition without filtration ranges from 60 to 1000 nm. After filtration, the maximum particle size in the film plane is less than 500 nm. Two types of irregularities are found on the surface after deposition: irregularities obtained from rounded particles and irregularities from faceted crystals. Using the methods of electron lithography and etching with argon ions through a mask, micro- and nanostructures are fabricated from HTS films. A correlation has been found between the characteristic dimensions of the irregularities on the surface of the films and the available lateral resolution of the microstructures obtained. For structures from HTS films that are asymmetric rings with a characteristic line width of 800 nm, the temperature dependences of the superconducting transition are determined and their asymmetric I–V characteristics are observed. [ABSTRACT FROM AUTHOR]