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Effect of oxygen on the characteristics of radio frequency planar magnetron sputtering plasma used for aluminum oxide deposition Investigation of induced recrystallization and stress in close-spaced sublimated and radio-frequency magnetron sputtered CdTe thin films Cadmium telluride oxide films (CdTe:O) were grown by a radio frequency sputtering technique using a controlled plasma (Ar-N 2 0) on glass slide substrates. The films were studied by Auger electron spectroscopy, x-ray photoelectron spectroscopy, and x-ray diffraction. We demonstrate that with N 2 0 the oxidation process occurs in a narrow range of partial pressures of nitrous oxide. We find that the films are amorphous and the amount of oxygen incorporated in the films depends on the N ° partial pressure and saturates at about 55 at. % oxygen. As the amount of oxygen increases the 2 • number of Te-O and Cd-O bonds increases. The compounds formed depend on the partIal pressure of the N 2 0 and are of the form Cd x TeyO z ' When saturation of oxygen is obtained the compound formed is probably CdTe20s.

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The local atomic structure of CdTe:In at an In concentration of 6 at. % was investigated by x-ray absorption spectroscopy before and after photoexcitation at 80 K. After photoexcitation, In K edge spectra change in both the near-edge and x-ray absorption fine structure (XAFS) regions, showing a change in local structure. Cd and Te structural parameters are consistent with the structure of CdTe and did not change after photoexcitation. For In, only the first shell contribution is present in the XAFS, indicating a disordered environment beyond the first shell of neighbors. The relation of these observations with the proposed model of a DX center for CdTe:In is discussed.

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Photoacoustic (PA) heat transmission measurements were used to study thermal transport in n-type polycrystalline CdTe films doped with metallic indium. Thermal diffusivity (TD) at room temperature was determined using an open cell PA technique. The TD obtained for each sample was correlated with x-ray diffraction measurements. It can be shown that the TD of the undoped films under investigation is significantly reduced compared with corresponding doped films. This reduction is a result of the high concentration of indium atoms and defects depending on the deposition parameters. It is shown that the effects of CdTe lattice shrink produced by indium doping, induces an increase in phonon scattering reflected in the large TD decrease even with moderated indium concentration. We have calculated the relation between the TD and the lattice parameter as a polynomial function α(cm 2 s −1 ) = −35225.2 + 14259a − 1532.7a 2 − 27.9a 3 + 8.4a 4 .

In this work, we present the stoichiometric behaviour of Ba 2+ and Sr 2+ when they are deposited to make a solid solution of barium strontium titanate. Ba x Sr 1−x TiO 3 (BST) thin films of nanometric order on a quartz substrate were obtained by means of in-situ RF-magnetron co-sputtering at 495 • C temperature, applying a total power of 120 W divided into intervals of 15 W that was distributed between two magnetron sputtering cathodes containing targets of BaTiO 3 and SrTiO 3 , as follows: 0-120, 15-105, 30-90, 45-75, 60-60, 75-45, 90-30, 105-15 and 120-0 W. Boltzmann's sigmoidal modified equation (Boltzmann's profile) is proposed to explain the behaviour and the deposition ratio Ba/Sr of the BST as a function of the RF-magnetron power. The Boltzmann's profile proposal shows concordance with experimental data of deposits of BST on substrates of nichrome under the same experimental conditions, showing differences in the ratio Ba/Sr of the BST due to the influence of the substrate.