Influence of oxygen partial pressure on the metastable copper oxide thin films

Abstract

Paramelaconite (Cu4O3) is a metastable copper oxide. Metastable copper oxide thin films were deposited on glass substrates by reactive RF magnetron sputtering in argon (Ar) and oxygen (O2) gas mixture atmospheres. Ar/O2 gas ratios in the sputtering ambient were chosen as 1/1 and 1/9. The surface and optical properties were determined by X-ray diffractometer (XRD), atomic force microscope (AFM) and UV-Vis spectrophotometer. The XRD patterns of the samples exhibited single strong diffraction peaks at 35.39[Formula: see text] and 35.49[Formula: see text], corresponding to the (202) peak of Cu4O3. The mean thickness values were measured as 100 nm and 80 nm for the films deposited at 1/1 and 1/9 Ar/O2 gas ratios, respectively. The samples showed low transmittance and high absorbance in the high frequency region.

Full‐Color Reflective Filters in a Large Area with a Wide‐Band Tunable Absorber Deposited by One‐Step Magnetron Sputtering

“…These results show that the adhesion strength for the samples of 0 O, 3 O, 7 O, and 10 O are 1.05, 1.21, 1.19, and 1.32 N, respectively. Each sample of MZC oxide thin films show similar but still relatively lower adhesion strength compared with the oxygen‐free sample due to the lower bombardment energy of O 2+ with respect to Ar + during sputtering …”

“…On the other hand, the adhesion strength between the thin films and substrate is also important for the practical applications. Therefore, the adhesion strength of all prepared samples is obtained by microscratch experiments, and the results are also summarized in Table [37] To investigate the optical properties of the top absorptive layer, we deposited a set of single layer MZC oxide films on quartz glasses with oxygen flux values from 3 sccm to 30 sccm. The simulated and measured transmittance spectra for four MZC oxide thin films with different oxygen contents (3 O, 5 O, 7 O, and 10 O) are plotted in Figure 2.…”

“…In addition, we observe that the contents of magnesium and zinc increase with increasing oxygen flow, while the calcium content decreases. We assume that the surface of the sputtering target was oxidized by a large amount of oxygen, reducing the sputtering yield of calcium oxide . In addition, the oxygen contents increase with increasing oxygen flux, but the oxygen also originates from native chemical absorption of oxygen from the air and substrate; thus, we will discuss this process in detail for the MZC oxide thin films.…”