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Low texture spreads of single‐crystalline‐like materials are critical for high performance of low‐cost flexible semiconductors and second‐generation high‐temperature superconductors based on metal foils. For texture improvement, a single‐crystalline‐like Ag film is epitaxially grown on an ion‐beam‐assisted deposition TiN substrate using magnetron sputtering. Ultra‐low texture spreads are found in the thin Ag film (∼330 nm), with an out‐of‐plane texture spread (Δω) of ∼1.03° and an in‐plane texture spread (Δϕ) of ∼1.34°. Compared with the texture spreads of the TiN substrate, Δω and Δϕ of the Ag film are reduced by ∼42 and ∼79%, respectively. Applying this Ag buffer, the texture spreads of a single‐crystalline‐like Ge film are reduced by ∼37% (Δω) and ∼36% (Δϕ). Factors contributing to the texture improvement by Ag are studied using single‐crystalline‐like Ag films with various thicknesses. [ABSTRACT FROM AUTHOR]

Nickel silicides are widely used as contact materials for electronic devices based on silicon (Si). However, they have been predominantly fabricated by annealing separate Ni and Si phases which leads to phase and structural complexity. In this letter, direct epitaxial growth of a single-phase nickel disilicide (NiSi2) thin film by sputter deposition of NiSi2 is achieved on low-cost and flexible Hastelloy tapes which offers a promising route to fabricate low-cost, flexible electronic devices. Biaxially textured titanium nitride (TiN) is applied as the seeding layer and the diffusion barrier under NiSi2. An epitaxial relationship of (001)⟨100⟩NiSi2 ǁ (001)⟨110⟩TiN is observed with an extra-large lattice mismatch (∼10.3%) between NiSi2 and TiN. Both the bonding similarity and the passivation effect by hydrogen promote the epitaxial growth of NiSi2 on TiN. The flat and smooth NiSi2 thin film consists of grains with a size of 50–100 nm. An epitaxially grown Si film on NiSi2 further demonstrates the potential of manufacturing high-performance Si flexible electronics with NiSi2/TiN/Hastelloy as the direct contact through this approach. [ABSTRACT FROM AUTHOR]

[Display omitted] • We achieved ultrathin epitaxial ZnO thin-film actuators on flexible Hastelloy tapes. • We discovered higher piezoelectric constants in thinner epitaxial ZnO thin films. • We demonstrated tunable linear piezoelectric properties in strained ZnO thin films. Linear piezoelectric materials and devices potentially serve as high-accuracy and fast-response sensors and actuators. However, linear piezoelectrics have been scarcely studied, while tuning the linear piezoelectric response of undoped ZnO remains a challenge. Here, linear piezoelectric zinc oxide (ZnO) thin film actuators are fabricated with a sandwich structure of AZO/ZnO/AZO epitaxially on CeO 2 /Hastelloy substrates, with AZO denoting the aluminum-doped ZnO electrodes and CeO 2 denoting the cerium oxide buffer. Due to the lattice mismatch between ZnO and CeO 2 , compressive in-plane lattice strains are detected. Through varying the ZnO layer thickness, a strong correlation is found between the in-plane epitaxial strain and the piezoelectric constant which proves an effective method to improve the linear piezoelectric response of ZnO. Further, the better linear piezoelectric response of the thinner flexible ZnO layer resolves the controversy between the performance and the deformation-durability of flexible piezoelectric ZnO devices. The vertical piezoelectric constant of the ultrathin (∼32 nm) ZnO film is ∼ 8.14 pm/V, which is highly suitable for positioners working at the picometer scale. Future works harnessing the epitaxial strains to further improve the piezoelectric constant of ZnO materials potentially lead to the prosperity of linear piezoelectrics. [ABSTRACT FROM AUTHOR]

• Niobium-doped indium oxide (InNbO) was prepared by co-sputtering technique. • InNbO is compact and uniform without obvious pores and cracks. • InNbO is cubic bixbyite polycrystalline structure. • The resistivity of InNbO is as low as 8.29 × 10–3 Ω· cm when the Nb content is 1.8 at%. • InNbO exhibits high optical transmittance from visible to near-infrared wavelength regions. Indium oxide (In 2 O 3) based thin films have attracted much attention due to their high transparency and low resistivity. In order to obtain good transmittance and high conductivity, niobium (Nb) element was chosen as dopant in In 2 O 3 in this study. Nb-doped In 2 O 3 thin films (InNbO) were deposited on substrate by co-sputtering technique. The influence of Nb content on the structural, optical and electrical properties of InNbO thin films was systematically investigated. These thin films are compact and uniform without obvious pores and cracks. And InNbO is cubic bixbyite structure similar to In 2 O 3. When Nb content is 1.8 at%, the resistivity of InNbO is as low as 8.29 × 10−3 Ω·cm. The prepared thin films exhibit high optical transmittance from visible to near-infrared wavelength regions. The average transmittance of InNbO thin films can reach 80.74 % in visible light range (380 ∼ 750 nm), and 75.71 % in near-infrared region (750 ∼ 2400 nm). [ABSTRACT FROM AUTHOR]