Rutherford backscattering spectrometry in the channelling mode using MeV He(+) ion beam is employed to measure 100 keV Al(+) and 450 keV Xe(+) ion implantation damage profiles in 4H-SiC as a function of implantation temperature and dose. The dechanneled fraction in the silicon sublattice has been evaluated and profiles of disordered silicon atoms are extracted from the measurements. Strong surface accumulation of disordered silicon atoms is observed. In addition it is found that the number of displaced silicon atoms normalized by the dose for 5x10(14) and 1x10(15) Al(+)/cm(2) implants follows an Arrhenius dependence in the temperature ranee of 25-400 degreesC and a preliminary value for the activation energy is in the range of 0.1 eV.