Studied are peculiarities of the changes in the structure and electrophysical properties of nanocrystalline silicon carbide films of 3C-SiC polytype subjected to the action of picosecond laser pulses with λ？=？355？nm and a pulse power up to 1.5？W. It is established that laser processing of the films with an energy density of 3 × 10？2？30？J/cm2 leads to ablation without decomposition of SiC. During the laser processing the electrical resistance of the films rises due to diminution of the film thickness. While measuring the PL properties of nc-SiC films under the influence of the applied electric field with intensity 3 × 103？V/cm, the effect of a single triple enhancement of the luminescence maximum is revealed. Repeated PL measurements at the same area of the film under the applied electric field with the intensity ranging from 0 to 1 × 104？V/cm show that the PL emission intensity diminishes at the short-wavelength boundary of the maximum and rises at the long-wavelength boundary. Thereat the spectral position of the PL maximum remains unchanged. 1. Introduction Nanocrystalline silicon carbide (nc-SiC) films are promising for micro- and nanomechanical systems used for registration, measurement, and analysis of different external factors, including most severe ones [1]. High resistance of SiC atomic structure to electromagnetic fields makes it possible to analyze the electronic properties of thin nc-SiC layers using high-power ultrashort laser pulses for excitation of the electronic subsystem. At the same time, irradiation of thin SiC layers by powerful femto- and picosecond laser pulses gives rise to the problems connected with possible changes in the structure and phase composition of the material under the action of high peak intensity electromagnetic pulses. The latter may stimulate photochemical reactions [2], surface local melting [3], and ablation [4]. In particular, it has been established in [5, 6], that such a treatment results in decomposition of crystalline silicon carbide into carbon and silicon phases, which cause the rise of the electric conductivity and the appearance of fused silicon in the treatment channel, respectively. At the same time, data on the use of high-power ultrashort laser pulses for the modification of the structure of nanocrystalline silicon carbide and investigation of its electronic are practically absent. Therefore, the aim of the present work was to study of the possibility to apply high-power picosecond laser irradiation for modification of the electrophysical properties of nc-SiC films and measurement of their
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