What could cause local microscopic morphology changes on a Nickel film deposited with DC Magnetron sputtering?

I am using an Si substrate and sputtering a Cr seed layer (~50 nm, for adhesion). After which I sputter the substrate with 1 um thick Ni film (150 W power, ~E-7 mTorr base pressure, 10 mTorr Ar...

03 March 2013 1,961 2 View