Communication—Growth of <111> Nanotwinned Nickel Films on <111> Nanotwinned Cu Substrates

Nickel has a high twinning energy of 110 MJ/m2, and it is thus difficult to fabricate nanotwinned Ni (nt-Ni) films. In this study, we adopt <111>-oriented nanotwinned Cu films as a substrate for the growth of nt-Ni films, and successfully electroplate <111>-oriented Ni films with densely-packed nanotwins. The average twin spacing is only 22 nm, while the grain size is over 1 μm. The nt-Ni film can be grown to a thickness of approximately 2.6 μm; beyond that, the Ni film becomes nanocrystalline. This approach provides a promising method to fabricate <111>-oriented nt-Ni films with controlled microstructures.