From the XPS results, it appears that the films were very rich in Al regardless of the mixing ratio of TDMAT to TDMAA. This can be explained by several reasons: i) Nucleation delay differences -both AlN ALD and TiN ALD have shown that nucleation is easy (no nucleation delays), as shown by both ALD processes exhibiting substrate-enhanced growth, i.e., GPC that is high at the very start of the deposition.