A novel and highly efficient methodology to regulate (enhance or suppress) the Volmer–Weber 3D growth mode of ultra‐thin (<10 nm) Ag layers by modulating the surface stoichiometry of ZnO substrates prior to Ag deposition is presented. Relative to pristine ZnO layers, oxygen‐deficient surface states formed by preferential removal of surface oxygen atoms remarkably improve Ag layer wettability, whereas oxygen‐excessive surface states formed by oxygen atom incorporation strongly facilitate Ag agglomeration. The dissimilar nucleation and coalescence dynamics are elucidated via combined molecular dynamics and force‐bias Monte Carlo simulations. The improved wettability results in significantly lower sheet resistance in the ultra‐thin (6–10 nm) Ag layers, for example, 6.03 Ωsq−1 at 8 nm, than the previously reported values from numerous other approaches in the equal thickness range. When this unique methodology is applied to ZnO/Ag/ZnO transparent electrodes, simultaneous improvement in electrical conductivity and visible transparency is realized, with a resultant Haacke figure of merit value of 0.139 Ω−1 that is >50% higher than the best reported value for an identically structured electrode. We select transparent heating devices as a model system to confirm that the superior optoelectronic properties are highly sustainable under simultaneous and severe electrical, mechanical, and thermal stresses.

No abstract

A methodology for the simultaneous modulation of the chemical and physical states of an amorphous TiO x layer surface and its impact on the subsequent deposition of a polycrystalline Ag layer are presented. The smoothened TiO x layer surface comprising chemically altered, oxygen-deficient states serves as a nucleating platform for Ag deposition, facilitating a marked increase (∼75%) in the nucleation number density, which strongly enhances the wettability of ultrathin Ag layers. The physically smoothened TiO x /Ag interface further reduces the optical and electrical losses. When the proposed methodology is applied to TiO x /Ag/ZnO transparent conductive electrodes (TCEs), exceptional TCE properties are yielded owing to the simultaneous improvement in visible transparency and electrical conductivity; specifically, a record-high 0.22 Ω −1 Haacke figure of merit is realized. TCEs are prepared on flexible substrates to verify their applicability as stand-alone flexible transparent heaters and as integrated heaters within electrochromic devices to enhance color-switching reactions.

In this study, we report a methodology that simultaneously improved the corrosion resistance and visible transparency of ZnO/Cu/ZnO transparent heaters with the addition of reactively sputtered Al2O3 layers. To assess corrosion resistance, ZnO and Al2O3 layers with thicknesses in the range of 0-20 nm were deposited onto 20 nm-thick Cu layer, and the corrosion behavior of the underlying Cu layers was investigated by evaluating the sheet resistance change in an 85 °C/85% humidity test. While the 20 nm-thick ZnO layer was not an effective moisture barrier, showing a sheet resistance increase of more than 50% after 10,000 m, the sheet resistance of the Cu layer below the 5 nm-thick Al2O3 layer did not show an observable increase for equal duration. Optical transmittance was also investigated by constructing glass/ZnO/Cu/ZnO/Al2O3 structures with varying thicknesses for the top ZnO and Al2O3 layers, in the range of 10-30 and 10-60 nm, respectively The thicknesses of the bottom ZnO and Cu layers were fixed at 30 nm and 10 nm. The results revealed that the average visible light transmittance of the ZnO/Cu/ZnO/Al2O3 structure increased by 2.5% over the optimized ZnO/Cu/ZnO structure.