HIGH-DOSE CARBON IMPLANTATION IN NICKEL

The diffusion of ion-implanted carbon in single crystal and polycrysta lline nickel has been investigated. 400 keV high dose (8 x 10(17)/cm2) carbon ions were implanted into nickel samples, followed by annealing in flowing Ar gas at temperatures ranging from 300 to 1010-degrees-C. The diffusion of carbon atoms was studied using Rutherford backscatte ring spectrometry (RBS) and non-Rutherford proton elastic scattering c ombined with the channeling technique. In the case of single crystal n ickel, segregation occurred at 400-degrees-C and significant carbon di ffusion was observed at 600-degrees-C. After long-term annealing at 85 0-degrees-C/4 h plus 470-degrees-C/4 h, no measurable carbon remained in the implanted layer. For polycrystalline nickel, the segregation of the implanted carbon also occurred at 400-degrees-C. All of the impla nted carbon was diffused out of the implanted layer at 650-degrees-C.