The formation of a stationary non equilibrium (s.n.e.) distribution function is studied numerically. To describe a weakly collisional space uniform plasma the non linear Landau-Fokker-Planck kinetic equation is used. A local (in momentum space) s.n.e. distribution can be formed inside the energy interval between the source and the sink of particles. The results can be used for the prediction of the semiconductor behaviour with an intrinsic as well as an extrinsic conductivity under the bombardment by fast ion beams.