Complex materials structures based on Cu-Al-O layer on silicon and fused silica were studied. The Al-O and Cu-O film was deposited by reactive sputtering method. We used a CO₂ laser and furnace methods to change the structure of the Cu-Al-O layer.
X-ray diffraction method was used ex situ to study the change of Cu-Al-O structure caused by post-deposition thermal treatment. The diffraction patterns were recorded on a state-of-the-art diffractometer (Philips X'Pert MPD, with CuKα₁ radiation; λ = 0.15406 nm) equipped with a Johansson monochromator and a linear semiconductor strip detector.
The optical constants and film thickness were determined using commercial software for data collected at an ellipsometer (WVASE 32).
For investigation of the influence of process-dependent properties of film morphology, the tapping-mode atomic force microscopy was used. Chemical analysis of the interface region was conducted by X-Ray Photoemission Spectroscopy (XPS).
Samples with silicon substrate after post-deposition annealing in furnace in the temperature range of 873 - 1373 K at 1 hour exhibit the layer transparency and p-type conductance. The XPS characteristic shows the peaks at 944 eV and 947 eV attributed for Cu₂O, which is a well-known p-type oxide semiconductor. The very thin Cu₂O layer was formed on the top of thin films. From the electrical measurements in the van der Pauw configuration the layer has a resistance per square of about 211 Ω, holes mobility of 50.5 cm²/ Vs and carrier density per square of about 5.8^. 10¹⁴/cm².