The paper presents preliminary results of the experiments performed to study the influence of low energy Ar ions on the electrical properties of p-InSb under ion beam milling. We demonstrate that this treatment causes the 2-layer structure with electron conductivity to emerge at the p-InSb surface. The first layer with low mobility electrons is created through the surface amorphisation by ion bombardment. The second layer with higher mobility electrons is a result of crystal lattice damages. The properties of the second layer are time-dependent that indicates the gradual relaxation of damages.