Cuprous oxide (Cu₂O) is a promising material for large scale photovoltaic applications. The efficiencies of thin film structures are, however, currently lower than those for structures based on Cu₂O sheets, possibly due to their poorer transport properties. This study shows that post-deposition rapid thermal annealing (RTA) of Cu₂O films is an effective approach for improving carrier transport in films prepared by reactive magnetron sputtering. The as-deposited Cu₂O films were poly-crystalline, p-type, with weak near band edge (NBE) emission in photoluminescence spectra, a grain size of ~100 nm and a hole mobility of 2 - 18 cm²/Vs. Subsequent RTA (3 min) at a pressure of 50 Pa and temperatures of 600 - 1000 °C enhanced the NBE by 2-3 orders of magnitude, evidencing improved crystalline quality and reduction of non-radiative carrier recombination. Both grain size and hole mobility were increased considerably upon RTA, reaching values above 1µm and up to 58 cm²/Vs, respectively, for films annealed at 900 - 1000 °C. These films also exhibited a resistivity of ~50 - 200 Ω cm, a hole concentration of ~ 10¹⁵ cm^-3 at room temperature, and a transmittance above 80.

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The effect of millisecond flash lamp annealing (FLA) on aluminum doped ZnO (AZO) films and their interface with Si have been studied. The AZO films were deposited by magnetron sputtering on Si (100) substrates. The electrical and structural properties of the film and AZO/Si structures were characterized by current-voltage, capacitance-voltage, and deep level transient spectroscopy measurements, X-ray diffraction, and secondary ion mass spectrometry. The resistivity of the AZO film is reduced to a close to state-of-the-art value of 2 Â 10 À4 X cm after FLA for 3 ms with an average energy density of 29 J/cm 2. In addition, most of the interfacial defects energy levels are simultaneously annealed out, except for one persisting shallow level, tentatively assigned to the vacancy-oxygen complex in Si, which was not affected by FLA. Subsequent to the FLA, the samples were treated in N 2 or forming gas (FG) (N 2 /H 2 , 90/10% mole) ambient at 200-500 C. The latter samples maintained the low resistivity achieved after the FLA, but not the former ones. The interfacial defect level persisting after the FLA is removed by the FG treatment, concurrently as another level emerges at $0.18 eV below the conduction band. The electrical data of the AZO films are discussed in term of point defects controlling the resistivity, and it is argued that the FLA promotes formation of electrically neutral clusters of Zink vacancies (V Zn 's) rather than passivating/compensating complexes between the Al donors and V Zn 's. Published by AIP Publishing.

Aluminum doped ZnO (AZO) has been deposited on (100), (110) and (111) oriented n-type Si and on fused silica by atomic layer deposition (ALD). The films have been post deposition annealed in the temperature range 200-500 οC. The AZO films have been characterized by X-ray diffraction (XRD), Hall and transmittance measurements. Circular diodes have been fabricated from the AZO/Si structures and characterized by current-voltage (IV) and deep level transient spectroscopy (DLTS). The AZO films form Schottky junctions with the Si substrates for all the crystallographic orientations. It is established that after post deposition annealing the structure AZO/n-Si (110) is distinguished as the system with largest rectification.

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