Abstract: Amorphous hydrogenated silicon carbide(aSiC:H) films were prepared by the reactive sputtering method,which were irradiated by high energy neutrons.Using resistivity,Raman scattering,and infrared transimissing spectroscopy,the authors investigated the neutrons irradiation effects on the structure and properties of a-SiC:H films.There were superfluous carbons in the films.It is found that the increase of irradiation doses results in the increase of SP-2C=C bonds in a-SiC:H films,i.e.the carbons in the films tended to graphitization.In general,the graphitization of carbons led to the decrease of resistivity sharply,but the decrease of resistivity in this paper was smooth .The phenomenon can be interpreted according to the model that the carriers were trapped by the defects.