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Hydrogen and Ga-codoped ZnO (HGZO) films caped with different thickness of Ga-doped ZnO (GZO) films (0–80 nm) were prepared by RF magnetron sputtering at room temperature, and the influences of GZO layer thickness and post-annealing treatment on structural, electrical and optical properties of the GZO/HGZO bi-layer films were investigated. The results show that increasing GZO layer thickness weakens the (002) preferred orientation, decreases the crystallize size and increases compressive stress of the films. The electrically conductive properties of the films first enhance and then degrade with increase of GZO layer thickness, and the best conductive properties can be obtained at GZO layer thickness of 20 nm. As GZO layer thickness increases, transmittance in visible range (T Vis) and bandgap (E g) of the films show a decreased trend, but their Urbach energy (E u) increases. The crystallite size of the films first greatly and then slightly increases with increasing annealing temperatures to 400 °C, and annealing atmosphere (air or vacuum) and time (10 min or 2 h) have little effect on the crystallite size at the same annealing temperature. With increasing annealing temperature, compressive stress greatly decreases firstly and then slightly decreases under vacuum annealing or converts to tensile stress under air annealing. The conductive properties of the films degrade after vacuum annealing for 2 h, but they degrade significantly even after air annealing for 10 min. Increasing GZO layer thickness can retard the decline of conductive properties of the films under vacuum annealing of 200–400 °C for 2 h or air annealing of 200–300 °C for 10 min. With increasing annealing temperature, the T Vis of the films basically shows a trend of first increase and then decrease, and the E g and E u of the films basically decrease. After annealing at 400 °C, the decreased E g and E u values of films under air annealing are close for different annealing time, but they are larger than those under vacuum annealing. Basically, thicker GZO layer is more likely to restrain the decrease of E g , but leads to obvious decrease of E u. In addition, effect of hydrogen doping and out-diffusion, crystallize growth and stress relaxation mechanism under annealing, and carrier transport and E g shift mechanisms are also discussed. • Effect of GZO layer thickness on structure and properties of GZO/HGZO bi-layer film is studied. • Thermal stability of bi-layer film is investigated under four annealing processes. • Effect of H doping and diffusion on structure and properties of film is analyzed. • Crystallize growth and stress relaxation mechanisms under annealing are discussed. • The carrier transport and E g shift mechanisms of the films are discussed. [ABSTRACT FROM AUTHOR]

Different thicknesses (2–250 nm) of Cu films were deposited on glass substrate by RF magnetron sputtering in Ar and Ar + H 2 atmospheres at room temperature. It is found that crystallinity and conductive properties of the films enhance but visible light transmittance (T Vis) decreases with increase of film thickness. Compared with the Cu films deposited in Ar, those deposited in Ar + H 2 have higher crystallinity and surface roughness, and they have better conductive properties and higher T Vis at film thickness above 5 nm. Overall, the Cu films deposited in Ar and Ar + H 2 can be achieved higher figure of merit (FOM) in a thickness range of 3~5 and 5~8.5 nm, respectively. Furthermore, the higher FOM values of Cu film deposited in Ar + H 2 atmosphere are higher than those of Cu film deposited in Ar atmosphere. The correlation between the improvement of transparent conductive properties of Cu films and modification of film microstructure due to introduction of H 2 into deposition atmosphere is discussed. • Cu films with different thicknesses are prepared in Ar and Ar + H 2 atmospheres. • The ρ , n , μ and R s of Cu films with different thicknesses are investigated. • High FOM of Cu films can be obtained by optimizing the film thickness. • Effect of introducing H 2 on structure and properties of Cu films is analyzed. • Transparent conductive properties of Cu films can be improved by introducing H 2. [ABSTRACT FROM AUTHOR]