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Manufacturing high‐quality zinc oxide (ZnO) devices demands control of the orientation of ZnO materials due to the spontaneous and piezoelectric polarity perpendicular to the c‐plane. However, flexible electronic and optoelectronic devices are mostly built on polymers or glass substrates which lack suitable epitaxy seeds for the orientation control. Applying cubic‐structure seeds, it was possible to fabricate polar c‐plane and nonpolar m‐plane aluminium‐doped zinc oxide (AZO) films epitaxially on flexible Hastelloy substrates through minimizing the lattice mismatch. The growth is predicted of c‐plane and m‐plane AZO on cubic buffers with lattice parameters of 3.94–4.63 Å and 5.20–5.60 Å, respectively. The ∼80 nm‐thick m‐plane AZO film has a resistivity of ∼11.43 ± 0.01 × 10−4 Ω cm, while the c‐plane AZO film shows a resistivity of ∼2.68 ± 0.02 × 10−4 Ω cm comparable to commercial indium tin oxide films. An abnormally higher carrier concentration in the c‐plane than in the m‐plane AZO film results from the electrical polarity along the c‐axis. The resistivity of the c‐plane AZO film drops to the order of 10−5 Ω cm at 500 K owing to the semiconducting behaviour. Epitaxial AZO films with low resistivities and controllable orientations on flexible substrates offer optimal transparent electrodes and epitaxy seeds for high‐performance flexible ZnO devices. [ABSTRACT FROM AUTHOR]

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]