In the present work, a numerical modelling of the processes of exposure and development of the resist during electron beam lithography on structures incorporating YBa2Cu3O7 high-temperature superconductor thin films is performed. The Monte Carlo method is used to simulate the penetration of accelerated electrons in the target and to obtain radial distributions of the absorbed electron energy density in the resist, during the irradiation of 125 nm polymethylmethacrylate resist layer/YBa2Cu3O7 film of thickness d = 0, 100 and 300 nm/SrTiO3 or MgO substrate at beam energies E-0 = 25, 50 and 75 keV. These distributions are approximated by an analytical function, called 'proximity function', whose parameters are calculated using an original Monte Carlo technique, and are used as input data in the modelling of the process of development of the electron resist. The results show that electron beam lithography on the above-mentioned targets is associated with an enhanced proximity effect in comparison with that on the conventional in microelectronics targets PMMA/Si substrate or PMMA/SiO/Si substrate, and it has to be taken into account in order to create patterns of intended dimensions.