The alloy composition dependence of penetration range and backscattering coefficient of electrons normally impinging on SixGe1−x and GaAsxN1−x semiconductor alloys targets for beam energies in the range 0.5–3.5 keV has been investigated. The electron penetration range is calculated using the Ashley's model. The electron backscattering coefficient is determined using both the Vicanek and Urbassek theory where the transport cross-sections are obtained more accurately via an improved approximation and Monte Carlo method in which the inelastic scattering processes are treated via Ashley's optical model. Our results regarding the electron backscattering coefficient for Si and Ge targets are found to be much higher than those of experiment when using the Vicanek and Urbassek theory. However, the use of Ashley's model via Monte Carlo method gives results that are in reasonably good accord with the experimental data reported in the literature in the low energy regime being considered here.