Kinetic Monte Carlo wurtzite structure crystals of 4H-SiC simulations were performed. The first stage of system evolution was the sublimation process which ended when bunched structure appeared. Then the crystal growth started. Vanishing of bunched structure and its transition to the double stepped one was observed on setting the proper parameters during growth up. For high incoming fluxes during growth 2D nucleation happened at wide terraces and surface debunching was blocked. Application of low resulting flux of incoming and out-coming particles have also blocked the surface smoothing process.