ALD of Hafnium Dioxide Thin Films Using the New Alkoxide Precursor Hafnium 3-Methyl-3-pentoxide, Hf(mp)4

This is the authors' abstract. We don't add key points for this paper.

A new alkoxide precursor, Hf(mp)4 [mp = 3-methyl-3-pentoxide, OC(CH3)(C2H5)2] has been employed in the atomic layer deposition (ALD) of HfO2 thin films using water (H2O) as the oxygen source. The self-limiting ALD process via alternate surface reactions of Hf(mp)4 and H2O is confirmed from thickness measurements of the HfO2 films grown with varied Hf(mp)4 supply time and number of Hf(mp)4/H2O ALD cycles. The ALD temperature window for this precursor is found to be between 250 and 350 °C. Under optimal reaction conditions, the growth rate of the HfO2 films is ∼0.9 Å per cycle. Amorphous films can be obtained across the entire temperature range with atomically flat and uniform surfaces. X-ray photoelectron spectroscopy (XPS) and depth-profiling Auger electron spectroscopy (AES) indicate that the films are stoichiometric with negligible amounts (less than 2 %) of carbon impurities.