Physica status solidi. C, Conferences and critical reviews/Physica status solidi. C, Current topics in solid state physics · 2010 · 70 citations · 0 references
Natural SciencesMaterials EngineeringMaterials ScienceInterface ScienceMaterials ChemistrySurface ScienceAluminum OxidesInterface EngineeringOxide SemiconductorsPlasma-surface InteractionsSurface Chemistry Of SolidsSurface PhysicsAnnealing Temperature EffectsBondingBonding StructureElastic RecoilInterfacial FilmsPlasma-assisted BondingPlasma-enhanced DepositionSubstrate Temperature Effects
Abstract A systematic study on the composition and bonding structure of plasma‐assisted ALD Al 2 O 3 films deposited at substrate temperatures between 25 and 400 °C is presented. The composition of the films is determined with Rutherford back scattering (RBS) and elastic recoil detection (ERD). The O/Al atom ratio in the films changes from 2.0 to 1.5 and the mass density increases from 2.6 to 3.1 g/cm 3 when increasing the substrate temperature. The hydrogen content decreases with substrate temperature from 13 at.% at 50 °C to less than 1 at.% at 400 °C. Fourier transform infrared spectroscopy shows that the H atoms are predominantly bonded to O atoms, and that the H atoms are effectively removed after annealing at 400 °C. Depth resolved XPS measurements reveal that the atomic concentrations remains constant after annealing. The O 1s and Al 2p XPS peak positions show that film has different bonding structure at the interface. compared to the bulk. After annealing the bulk of the film shows indications of relaxation whereas the interface is unchanged. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)