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Abstract The structural and optical characterizations of titania incorporated with alumina nanocrystals have been presented in this paper and the films exhibit excellent properties like low current density, small hysteresis as well as high photoluminescence quantum yields of about 361 nm. These properties are promising for the applications in future electronic devices.

Amorphous films Zr0.8Si0.2O2 were deposited on quartz substrates at room temperature, by using pulsed laser deposition technique. After annealing at high temperature, Zr0.8Si0.2O2 films suffer a phase separation to precipitate tetragonal ZrO2 nanocrystals in ZrSiO4 amorphous matrix. Their crystal structure, microstructure, optical absorbance and photoluminescence have been systematically investigated. Tetragonal ZrO2 nanocrystals show intense UV emission around 392 nm under photonic excitation with a wavelength of 250 nm. The corresponding models of electronic excitation and transition related to UV emission also have been proposed. [ABSTRACT FROM AUTHOR]

(ZrO2) x (SiO2)1− x (Zr-Si-O) films with different compositions were deposited on p-Si(100) substrates by using pulsed laser deposition technique. X-ray photoelectron spectra (XPS) showed that these films remained amorphous after annealing at 800°C with RTA process in N2 for 60 s. The XPS spectra indicated that Zr-Si-O films with x=0.5 suffered no obvious phase separation after annealing at 800°C, and no interface layer was formed between Zr-Si-O film and Si substrate. While Zr-Si-O films with x >0.5 suffered phase separation to precipitate ZrO2 after annealing under the same condition, and SiO2 was formed at the interface. To get a good interface between Zr-Si-O films and Si substrate, Zr-Si-O films with bi-layer structure (ZrO2)0.7(SiO2)0.3/(ZrO2)0.5(SiO2)0.5/Si was deposited. The electrical properties showed that the bi-layer Zr-Si-O film is of the lowest equivalent oxide thickness and good interface with Si substrate. [ABSTRACT FROM AUTHOR]

The tunable property and thermal stability of (Ba0.25Pb0.25)Sr0.5TiO3 films derived by pulsed laser deposition have been investigated. The substitution of Pb for Ba in (Ba,Sr)TiO3 (BST) system has been revealed to raise the transition temperature close to room temperature (RT) and enhance the tuning property. It is proposed that nanopolar regions would occur in the films in the paraelectric state at RT, arising from the addition of Pb2+ into the A site of pervoskite structure of BST. This induces the relaxor behavior and diffuse phase transition. Hence, low temperature-dependent tunability is obtained due to the broadening of dielectric constant peak. These results demonstrated that Pb substitution could be a simple and effective method to obtain high tunability and good temperature stability simultaneously. [ABSTRACT FROM AUTHOR]

Abstract: Unipolar resistive switching behavior has been investigated in Pt/Co3O4/Pt stacks. The resistance ratio of the high- and low- resistance states is over 5×103. The “ON/OFF” operation of the memory cells can be repeated more than 200 times at room temperature. The resistance of the two states can be kept for more than 16h without showing degradation. The temperature dependence of the resistance shows a metallic behavior at the low-resistance state, but a semiconductor-behavior at the high-resistance state. The mechanism responsible for the observed unipolar resistive switching behavior has been discussed. [ABSTRACT FROM AUTHOR]