Possible substrate effects -AlN and TiN possibly nucleate differently on different substrates. In trying to address this, in addition to Si, we tried deposition on different substrates: Al2O3, SiC and TiN-coated Si. The Ti at.% in all three samples were similar (8.8 %, 8.6 % and 8.5 % respectively), showing that AlN always nucleates faster and more efficiently than TiN regardless of the substrates, at least, for the investigated substrates.