First-principles characterization of a heteroceramic interface: ZrO2„001... deposited on an a-Al2O3„11̄02... substrate
نویسندگان
چکیده
We have studied an alumina/zirconia interface using the all-electron projector augmented wave formalism within density functional theory. We present the electronic, structural, and energetic properties of the ZrO2(001)/a-Al2O3(11̄02) interface as well as of the free a-Al2O3(11̄02) and ZrO2(001) surfaces. We find that the generalized gradient correction significantly lowers the oxide surface energies, compared to values obtained by the local density approximation. The monoclinic-tetragonal transition in ZrO2(001) thin films is discussed as well as strain effects involved in the interface formation. The stoichiometric alumina/zirconia interface is found to be weakly bonded, regardless of the film thickness, and the ZrO2(001)/a-Al2O3(11̄02) interface has a rather epitaxial character, due to a low lattice mismatch of ;4%. The impact of such weak interactions on ceramic coating stability is discussed.
منابع مشابه
Growth of nanolaminate structure of tetragonal zirconia by pulsed laser deposition
Alumina/zirconia (Al2O3/ZrO2) multilayer thin films were deposited on Si (100) substrates at an optimized oxygen partial pressure of 3 Pa at room temperature by pulsed laser deposition. The Al2O3/ZrO2 multilayers of 10:10, 5:10, 5:5, and 4:4 nm with 40 bilayers were deposited alternately in order to stabilize a high-temperature phase of zirconia at room temperature. All these films were charact...
متن کاملAdhesion of ultrathin ZrO2„111... films on Ni„111... from first principles
We have studied the ZrO2~111!/Ni~111! interface using the ultrasoft pseudopotential formalism within density functional theory. We find that ZrO2(111) adheres relatively strongly at the monolayer level but thicker ceramic films interact weakly with the Ni-substrate. We argue that the cohesion changes character from dominantly image charge interactions for thick ceramic films to more covalent fo...
متن کاملCharacterization of Pulsed Laser Deposited Al2O3 Gate Dielectric
The demands of future CMOS devices require a new gate dielectric material with higher dielectric constant than SiO2. Aluminum oxide is one of the high-k materials and an interesting candidate. Thin Al2O3 layers have been deposited by pulsed laser deposition (PLD) from a mono-crystalline sapphire target. This deposition technique was chosen because of its flexibility and availability. Aluminum o...
متن کاملRole of Surface Orientation on Atomic Layer Deposited Al2O3/GaAs Interface Structure and Fermi Level Pinning: A Density Functional Theory Study
Related Articles Spectroscopic refractive indices of monoclinic single crystal and ceramic lutetium oxyorthosilicate from 200 to 850nm J. Appl. Phys. 112, 063524 (2012) Valence band offset at Al2O3/In0.17Al0.83N interface formed by atomic layer deposition Appl. Phys. Lett. 101, 122110 (2012) Electronic structure and optical properties of β-FeSi2(100)/Si(001) interface at high pressure Appl. Phy...
متن کاملReforming of Biogas over Co- and Cu-Promoted Ni/Al2O3-ZrO2 Nanocatalysts Synthesized via Sequential Impregnation Method
Utilization of active and stable catalyst could have enormous advantages in industrial application of biogas reforming. In order to achieve this goal, the effects of Cu and Co as promoters were investigated over physical-chemical properties of Ni/Al2O3-ZrO2 catalyst in reforming of biogas. The sequential impregnation was used for preparation of catalysts. The catalysts were characterized using ...
متن کامل