FTIR results from cuprous oxide (Cu2O) and cupric oxide (CuO) films prepared by MOCVDtechnique were presented. According to FTIR and XRD results, Cu2O films can be prepared by MOCVD using 0.20 tort of copper acetylacetonate (Cu(acac)2) vapor and 150 torn of oxygen, at a deposition temperature of 340°C. The strong reductive tendency of Cu(acac)2 vapor in the MOCVD process is noted, as the oxidation state of copper was reduced from 2+ in Cu(acac)2 to 1+ in the Cu2O film. Cu2O films have a strong IR absorption band at 610 cm−1. CuO films were prepared at 0.20 tort of Cu(acac)2 vapor and 190 torr of oxygen, at a deposition temperature of 420°C. The IR bands of CuO films located at 440 cm−1, 480cm−1, and 540cm−1. The XRD results indicated that Cu2O films have a preferential orientation at (111) plane. From IR study, it appears that the MOCVD processing condition has an impact on the film microstructure, which in term influenced the band position and band shape of corresponding IR bands.

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Spectrally selective Al/AlN/Al/AlN tandem solar absorbers were deposited onto soda lime glass substrates using inline ac magnetron sputtering in a reactive atmosphere containing argon and nitrogen. To achieve a reproducible and homogenous deposition process, the deposition of multilayer Al/AlN/Al/AlN films under different process conditions was investigated. Two main variables, ac power and the speed of substrate movement in the chamber, were varied in the ranges of 1-10 kW and 10?47-31?4 mm s 21 respectively to obtain films with high absorption and low emittance. The effects of film thickness of different layers and deposition conditions on the optical performance of selective coatings were also studied. Structural features and surface morphology of the films were investigated by X-ray diffraction and field emission scanning electron microscopy analyses respectively. In the present study, tandem solar absorber films deposited onto glass substrate with optimised sputtering parameters can consistently achieve solar absorptance a of 0?864 and thermal emittance e of 0?03 at 80uC.

Copper oxide films were prepared by organometallic chemical vapor deposition of copper acetylacetonate in an oxygen-rich environment. The films were characterized by X-ray diffraction, Auger electron spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. At 360 °C, Cu2O films were formed for an oxygen pressure of 150 torr and a copper acetylacetonate vapor pressure of 0.2 torr). The Cu2O film was polycrystalline, but the orientation was primarily [111]. Differential scanning calorimetry indicated that O2 assists decomposition of the organometallic precursor during pyrolysis.

This paper reports preparation of highly oriented (002) ZnO films by atmospheric pressure CVD at 320°C, which is far below previous reported values. In this study, a cold wall horizontal system was used to thermally decompose sublimed zinc acetylacetonate (Zn(acac)2, Zn(C5H702)2) vapor, and reacted with water vapor to produce ZnO films at temperatures above 320°C. Through experimental data, we discovered that low deposition temperature, using water vapor as co-reactant and substrates with ZnO buffer layer pre-coated by PVD are the key factors to prepare (002) ZnO films. By using Si(100) pre-coated with sputtered ZnO amorphous buffer layer as substrates, the ZnO growth rate is highest. While using copper oxide pre-coated Si substrates gave the lowest growth rate, and deposited ZnO film is amorphous. Considering influence of CVD co-reactant, using Zn(acac)2 and water vapor gives higher growth rate and better crystallinity than CVD using Zn(acac)2 and oxygen. Water vapor may supply hydrogen to react with released acetylacetonyl ligand (C5H7O2), and help the formation of stable acetylaceton (C5H8O2) molecule. DPA shows that film contain 46% O and 54% Zn. XPS of Zn Auger identified the valence of Zn being Zn2+. It seems that excessive Zn might present as discrete Zn2+ dispersed between ZnO lattices.