Growth, interfacial microstructure and optical properties of NiO thin films with various types of texture

Abstract

NiO thin films with random, fiber and in-plane textures have been successfully deposited at near room temperature by reactive magnetron sputtering on glass, silicon and Al 2 O 3 (0001) substrates. Self-texture related with the deposition conditions and crystallographic characters competes with the driving force from the matched substrate. Such a competition can be used to control the texture of thin films on matched substrates, especially when the promoting orientations from self-texture and substrate are different. Enhancing this competition tends to suppress the selftexture of NiO thin films on Al 2 O 3 (0001) substrates, whereas restricting the competition is beneficial to produce the in-plane textured NiO thin films. In addition, it is found that the optical transmittance of NiO thin films on Al 2 O 3 (0001) substrates can also be tuned by such competition. Interfacial microstructure analyses of NiO thin films on amorphous substrates clearly evidence the existence a nanocomposite layer at the initial growth, which is composed of NiO nanocrystals surrounded by amorphous matrix. In contrast, in-plane textured NiO thin films on Al 2 O 3 (0001) substrates exhibit sharp interface without nanocrystals or amorphous matrix. We believe these results provide a general framework of tuning the textures and properties of thin films on matched substrates.

Deep-Ultraviolet Photodetection Using Single-Crystalline β-Ga2O3/NiO Heterojunctions

“…Electrical Characterization of Grown Thin Films and Heterojunction Diode. Figure 2a shows the XRD measurements of the single-crystalline films, manifesting (2̅ 01)-oriented β-Ga 2 O 3 and (111)-oriented cubic NiO films on c-plane sapphire, 38,39 whereas Figure 2b shows the measured RBS curves for thinner NiO and β-Ga 2 O 3 films on sapphire, confirming the stoichiometry of each layer and the well-defined interfaces. It can be seen that the Ni and Al signals overlap with that of Ga and O, respectively; the Ir and Ag signals originate from the metallic layer sputtered onto the sample before the RBS experiment in order to avoid electrostatic charging.…”

Investigating the Structure, Microstructure, and Texture in Selective Laser-Melted Sterling Silver 925

“…Wang et al emphasized the importance of understanding and controlling material texture since it influences mechanical and chemical properties. [28] Thermomechanical processing has been used on cast materials to change the texture and, as a result, the properties of the materials. [29] Wei et al have shown that AM offers much more flexibility in controlling the textures and properties of a material.…”

Tuning the Electrical Properties of NiO Thin Films by Stoichiometry and Microstructure

“…Intensive {111} diffraction peaks of NiO are clearly detected, indicating the high <111> orientation along the c-axis. Additionally, φ-scan diffractogram of the (200) (ψ = 54.7) plane shows six peaks with intervals of 60 • (see Figure 5b), which indicates the epitaxial growth of NiO thin films [37]. Epitaxial NiO thin films exhibit much stronger diffraction intensity and smaller full width at half maximum (FWHM) values than those on non-matched glass or Si substrates (see Figure 1), even though they are deposited at the same time.…”