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Single-phase CuInSe2 films were grown by high vapor selenization of CuIn alloy precursors within a partially closed graphite box. The CuIn precursors were prepared using CuxIny alloy targets with different composition rates under low vacuum level by a homemade sputtering system. The Cu and In composition rates of the used targets are 11:9, 10:10, and 9:11, respectively. The metallic precursor films were selenized using a two-step temperature profile, i.e. at 250°C and 400–500°C, respectively. The influence of the temperature at the second selenization step on the quality of the CIS absorbing layers was investigated. The CIS films were characterized by X-ray diffractometry, scanning electron microscopy, energy dispersive X-ray analysis, and Raman spectroscopy. The deposited CIS absorbers selenized at a high temperature of 500°C for 30 min exhibited a single-phase chalcopyrite structure with a preferential orientation in the (112) direction. These layers display uniform, large, and densely packed crystals with a grain size of about 3–5 μm. Cadmium sulfide buffer layer was manufactured by chemical bath deposition method. Bilayers ZnO/ZnO:Al were prepared by RF magnetron sputtering deposition. CIS solar cells with an efficiency of about 6.5% were produced without antireflective films. The method to fabricate CIS solar cells by a combination of the low vacuum sputtering deposition and the graphite box selenization process has provided a simple control process and shown a promising potential for developing high efficient and low-cost CuInSe2 solar cells. [ABSTRACT FROM AUTHOR]

Intrinsic zinc oxide (i-ZnO) film was prepared for CuInSe2 (CIS) solar cell application [L. Stolt and J. Hedstrom, Appl. Phys. Lett.62 (1993) 8; D. Rudmann, Ph.D. Thesis, University of Basel, Basel, (2004)] on glass substrate by inductively coupled plasma (ICP)-assisted DC magnetron sputtering and under a quite low temperature of 50°C. The sputtering was done in an Ar and O2 gas mixture and a ceramic ZnO target was used. The microstructures of the film were investigated by X-ray diffractometer and scanning electron microscope. It was shown that all of the films had a c-axis preferred orientation perpendicular to the substrate. In our work, film with resistivity of 7 × 108Ω·cm and transmittance of about 80% in the visible range was prepared under the conditions of 4 mTorr working pressure and 50°C temperature. [ABSTRACT FROM AUTHOR]

Indium tin oxide (ITO) thin films were prepared by radio frequency (RF) magnetron sputtering and under a quite low vacuum level of 2.3 × 10-3Pa. The sputtering was done in an Ar and O2 gas mixture at a temperature of 200°C. A ceramic In2O3:SnO2 target (10 wt% SnO2) was used. The microstructures of the films were investigated by a field emission scanning electron microscope (FESEM) and an X-ray diffractometer (XRD). X-ray photoelectron spectroscopy (XPS) was performed to characterize the composition of the films. ITO films with a high transparency in the visible wavelength range (80–95%) were obtained. The dependency of the electrical, optical and structural properties of ITO films on both the O2 flow ratio (O2/(O2 + Ar)) and the working pressure was investigated. In the case of low working pressure (1 Pa), the more highly transparent and conducting films were produced at the lower O2 flow ratio. High working pressure (2 Pa) gave rise to low quality, low transparency and amorphous films. Under RF sputtering at low vacuum level, the main contribution to the chamber atmosphere is due to water vapor. Oxygen originating from water vapor dissociation induced by plasma plays the same role as an oxygen or water vapor flux usually intentionally introduced in the system in order to have good quality films. [ABSTRACT FROM AUTHOR]

Polycrystalline silicon carbide (P-SiC) films containing SiC nanoparticles and Er were prepared by r.f. reactive magnetron co-sputtering technique with SiC and Er targets on low-temperature silicon (111) and silicon dioxide substrates with the mixed gas of pure argon, methane, and hydrogen. Surface morphology and photoluminescence (PL) properties of them were measured by field-emission scanning electron microscope and Raman spectroscopy. The peak position, intensity, and the full width at half maximum (FWHM) of PL spectra were relevant with Er doping levels and deposition conditions. [ABSTRACT FROM AUTHOR]