Influences of different oxidants on characteristics of LaO/AlO nanolaminates deposited by atomic layer deposition**Project supported by the National Natural Science Foundation of China (Grant Nos. 61604016 and 51501017) and the Fundamental Research Funds for the Central Universities, China (Grant No. 310831161003).

Abstract

A comparative study of two kinds of oxidants (H2O and O with the combination of two metal precursors (TMA and La(PrCp) for atomic layer deposition (ALD) La2O3/Al2O3 nanolaminates is carried out. The effects of different oxidants on the physical properties and electrical characteristics of La2O3/Al2O3 nanolaminates are studied. Initial testing results indicate that La2O3/Al2O3 nanolaminates could avoid moisture absorption in the air after thermal annealing. However, moisture absorption occurs in H2O-based La2O3/Al2O3 nanolaminates due to the residue hydroxyl/hydrogen groups during annealing. As a result, roughness enhancement, band offset variation, low dielectric constant and poor electrical characteristics are measured because the properties of H2O-based La2O3/Al2O3 nanolaminates are deteriorated. Addition thermal annealing effects on the properties of O3-based La2O3/Al2O3 nanolaminates indicate that O3 is a more appropriate oxidant to deposit La2O3/Al2O3 nanolaminates for electron devices application.