The spatial distributions of absorbed electron energy density in PMMA on structures incorporating YBa2CU3O7 high-T(c) superconducting thin films deposited on different substrates were determined using a Monte Carlo simulation (MCS), which takes into account the exact boundary conditions on interfaces between different layers of the target. The ability of our Monte Carlo program to accurately simulate the radial exposure distributions was demonstrated. The effects of substrate material (SrTiO3 and MgO), beam energy (40 and 80 x 10(-16) J) and high-temperature superconducting (HTS) film thickness (100 and 300 nm) on these distributions were investigated. The distributions obtained in this work can further be employed in a proximity effect correction algorithm as well as in a proper development model.