Thin high-k dielectric layers deposited by ALD

In this paper first results on the growth of thin layers of Al₂O₃, HfO₂ and nanolaminates of them, by atomic layer deposition are reported. The electrical characterization of the deposited layers has been carried out by means of the analysis of the capacitance-voltage and current-voltage characteristics of aluminum-high-k dielectric-silicon capacitors. The obtained results show that for the same physical thickness, HfO₂ layers are leakier than Al₂O₃ layers and that a nanolaminate stack of them improves the performance of the dielectric in terms of current and breakdown voltage although at the expense of a higher EOT.