Carbon-induced amorphous surface layers in Ti-implanted Fe

Titanium implantation into high-purity Fe is shown to produce a ternary amorphous surface layer consisting of not only Fe and Ti, but also C. The amorphous layer forms at the surface and grows inward with increasing Ti fluence. The amount of C present also increases with Ti fluence and is believed to be deposited on the surface from the vacuum during implantation and to subsequently diffuse into the sample to produce the amorphous layer. For Ti concentrations ≲10 at.%, the amorphous layer thickness is less than the depth of the implanted Ti, but agrees with C diffusion distances, thus demonstrating that C is an essential constituent of the amorphous phase.