Structure–properties relationship in reactively sputtered Ag–Cu–O films

Abstract

Ag–Cu–O films were deposited on glass substrates by pulsed dc sputtering of a silver–copper target (Ag50Cu50) in reactive Ar–O2 mixtures. The film chemical composition was estimated by x-ray energy dispersive spectrometry and the structure was studied by x-ray diffraction (XRD). Optical properties (reflectance and transmittance) and room temperature electrical resistivity were evaluated using spectrophotometry and the four point probe method, respectively. Since silver atoms are less reactive versus oxygen than copper ones, the increase in the oxygen flow rate introduced into the deposition chamber induced the preferential oxidation of sputtered copper atoms. XRD analysis showed that the structure of the deposited films can be divided into three domains. At low oxygen flow rate, the films were biphased (metallic silver-based solid solution and crystalline copper-based oxide). At intermediate oxygen flow rate, the films were x-ray amorphous (grain size lower than 2 nm). At high oxygen flow rate, the films contained a crystalline silver–copper oxide phase and a crystalline unknown phase. Thanks to the absorption band of silver in the UV range, reflectance measurements were used to show the occurrence of metallic silver phase in the films. It was shown that the chemical environment of silver atoms in the x-ray amorphous region evolved from metallic to oxide when the oxygen flow rate increased. Transmittance evolution versus the oxygen flow rate were well correlated with that of the electrical resistivity. The evolution of Ag–Cu–O film properties was discussed in connection with the structure and chemical composition.

Growth, electrical and optical behaviour of nanocrystalline Ag2Cu2O3 films produced by RF magnetron sputtering

“…For moderate to highly reactive chemical system, the reactive sputtering process comes with the abrupt decrease in the deposition rate when the sputter process turned in to so called reactive sputter mode [15]. Similar decrease in the deposition rate was also noticed in DC reactive sputtered Cu 2 O films deposited with copper target [16] and Ag-Cu-O films formed with Ag 50 Cu 50 target [10]. The chemical composition of the deposited films was determined by using energy dispersive X-ray analysis.…”

“…Pititjean et al [9] reported on the influence of annealing temperature on the decomposition, and structural and properties relationship in reactively sputtered Ag 2 Cu 2 O 3 films formed with Ag 50 Cu 50 sputter target. Pititjean et al [10][11][12] studied the effect of oxygen flow rate on the structure and properties of pulsed DC sputtered Ag-Cu-O films deposited using Ag 60 Cu 40 target. The effect of deposition temperature on the structural and optical properties of RF magnetron sputtered Ag 70 Cu 30 target was systematically studied [13].…”

Structural, Electrical, and Optical Properties of Reactively Sputtered Ag-Cu-O Films

“…For moderate to highly reactive chemical system, the reactive sputter process comes with the abrupt decrease in the films deposition rate when the process turned into the so-called reactive sputter mode [16]. Such a decrease in the deposition rate with the increase of oxygen partial pressure was also reported in the deposition of DC reactive magnetron sputtered silver oxide films [17] formed with silver target, cuprous oxide films [18] formed with copper target and Ag-Cu-O films with Ag 50 Cu 50 target [19]. Figure 2 shows the representative X-ray energy dispersive spectrum of the Ag-Cu-O film formed of oxygen partial pressure of 2 × 10 −2 Pa.…”

Tailoring assemblies of plasmonic silver/gold and zinc–gallium layered double hydroxides for photocatalytic conversion of carbon dioxide using UV–visible light

“…The interatomic distance (R) and its associated coordination number (N) for the Ag-Ag, Ag-O, and Au-Au pairs were set to 0.288 9 nm with the N value of 12 [29], 0.204 4 nm with the N value of 2 [30], and 0.288 4 nm with the N value of 12 [31], respectively. The many-body reduction factor S 0 2 was assumed to be equal for both the sample and the reference.…”