In this study, the surface morphology of electrodeposited Ni on
single crystal GaAs (001) was investigated by atomic force microscopy
(AFM). The images show granular deposits with stepped contours typical
of single-crystalline grains. The correlation length correlates very
well with the size of the grains, indicating that the layers grow as
columns with diameter increasing with thickness. This growth mechanism
is observed for layers with thicknesses in the range of 10 to 500 nm at
a deposition rate of ~0.5 nm/s.