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A series of [FeCo-O/SiO] multilayer thin films with different SiO separate layer thicknesses ( t=0-3 nm) and fixed FeCo-O layer thickness (5.4 nm) have been fabricated on (100) silicon and glass substrates by reactive magnetron co-sputtering. Microstructure analysis and magnetic measurement results show that FeCo-O grain size and magnetic properties can be adjusted by varying the thickness of SiO layers. All films reveal an evident in-plane uniaxial magnetic anisotropy (IPUMA) when the thickness of SiO monolayer changes from t=0 to 3 nm. The hard axis coercivity ( H) reveals a minimum of 9 Oe at t=1 nm while the easy axis coercivity ( H) exhibits a minimum of 16 Oe at t=2 nm. For t=1 nm and 2 nm, the IPUMA fields ( H) are 95 and 207 Oe, the saturation magnetizations ( M) are 1.8 and 1.6 T, the real part of the complex permeabilities (below 3.0 GHz) are more than 217 and 104, and the ferromagnetic resonance frequencies ( f) are 3.6 and 5.2 GHz, respectively. [ABSTRACT FROM AUTHOR]

The heating behavior of La NiO3 ( LNO) films on SiO2/ Si substrate heated by 2.45 GHz microwave irradiation in the microwave magnetic field was first investigated, and then amorphous Pb( Zr0.52 Ti0.48) O3 ( PZT) thin films were deposited on LNO-coated SiO2/ Si substrates by a sol-gel method and crystallized in the microwave magnetic field. The crystalline phases and microstructures as well as the electrical properties of the PZT films were investigated as a function of the elevated temperature generated by microwave irradiation. The perovskite PZT films with a highly (100)-preferred orientation can be obtained by microwave annealing at 700°C for only 180 s of total processing time, and have good electrical properties. The results demonstrated that conductive metal oxide LNO as a bottom electrode layer is an advantage for the crystallization of PZT thin films by microwave irradiation in the microwave magnetic field. [ABSTRACT FROM AUTHOR]

Transmission electron microscopy and small-probe microanalysis have been used to investigate the microstructure of HgCdSe thin films grown by molecular beam epitaxy on ZnTe/Si(112) and GaSb(112) substrates. The quality of the HgCdSe material was dependent on the growth temperature and materials flux, independent of the substrate. Samples grown at 100°C were generally of high quality, while those grown at 140°C had {111}-type stacking defects and increased dislocation densities. Improved preparation of the GaSb buffer layer should be developed for future HgCdSe growth on GaSb(112) substrates. [ABSTRACT FROM AUTHOR]

Abstract: Er-doped ZnO films were deposited by reactive magnetron sputtering technique at different oxygen flow rate. The microstructures, the chemical state of the oxygen and the optical absorption properties of ZnO:Er films were investigated. The X-ray diffraction spectroscopy (XRD) results and the X-ray photoelectron spectroscopy (XPS) analyses about the oxygen in the doped samples indicated that oxygen flow rate has great effect on the crystalline quality of ZnO:Er films. It was concluded that the decrease of the crystalline quality of the samples was caused by the oxygen deficiency. The optical absorption properties and the shift of the optical band gaps were investigated. The analysis reveals that the blue shift of the band gaps was caused due to the decreasing of O2−ions at the intrinsic sites and the increasing of O2-ions at the oxygen deficient regions. [Copyright &y& Elsevier]

Abstract: Er-doped ZnO films were deposited by direct current co-reactive magnetron sputtering technique and the microstructure and the optical properties of the ZnO films were investigated. XRD analysis reveals that the substrate temperatures have an evident effect on the (002) preferential orientation and the Er-doped ZnO film deposited at room temperature consists of an amorphous phase. The blue shift of the optical band gap was observed in the ZnO:Er films compared with undoped ZnO film, and the Er-doped ZnO film deposited at room temperature has the largest band gap (about 3.99eV). The main reason for the broadening of the band gap is attributed to the amorphous phase in the Er-doped ZnO film. Meanwhile, the red shift of the band gap in the ZnO:Er films deposited at high temperature was observed as the crystallinity of the fim became better. [Copyright &y& Elsevier]

An improved chemical bath deposition (CBD) technique has been provided to prepare zinc sulfide (ZnS) thin films on glass substrates deposited at 80–82°C using a mixed aqueous solution of zinc sulfate, ammonium sulfate, thiourea, hydrazine hydrate, and ammonia at the alkaline conditions. Both the traditional magnetic agitation and the substrates vibration by hand frequently were done simultaneously during the deposition. The substrates vibration reduced the formation and residence of gas bubbles on the glass substrates during growth and resulted in growth of clean ZnS thin films with high quality. Ammonia and hydrazine hydrate were used as complexing agents. It is found that hydrazine hydrate played an important role in growth of ZnS films. The structure and microstructure of ZnS films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and UV-vis spectroscopic methods. The XRD showed a hexagonal structure. The formed ZnS films exhibited good optical properties with high transmittance in the visible region and the band gap value was estimated to be 3.5–3.70 eV. [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]

High temperature ferromagnetism and perpendicular magnetic anisotropy were observed in Fe-doped In2O3 magnetic semiconductor films deposited on R-cut sapphire by pulse laser deposition. The films show a Curie temperature as high as 927 K. Strong perpendicular magnetic anisotropy with a remnant magnetization ratio of 0.77 and a coercivity of 680 Oe is demonstrated. Extensive microstructure, composition, and magnetic studies indicate that Fe element incorporates into the indium oxide lattice by substituting the position of indium atoms, which suggests the observed ferromagnetism is intrinsic rather than from Fe clusters or any other magnetic impurity phases. [ABSTRACT FROM AUTHOR]

The microstructure, ordering parameter, and magnetic properties of multilayer [FePt(x)/Os]n films on glass substrate by dc-magnetron sputtering (with x being thickness in nm; Os with a fixed thickness 5 nm; n being the number of layers) have been studied as a function of the annealing temperatures between 300 and 900 °C. The grain size of multilayer films can be controlled by annealing temperature and thickness of the FePt layer with Os space layer. The coercivity as a function of the annealing temperature for samples with n = 1 and pure FePt behaves roughly saturated after annealing above 700 °C. However, for samples with n > 4 the value of Hc seems still increasing with increasing annealing temperature between 600 and 900 °C, and the ordering parameter decreases with increasing the number of Os layers. Our experimental results are reasonably well to describe the effect of strain-assisted transformation. [ABSTRACT FROM AUTHOR]

Abstract: The tetragonal (Pb0.8Ca0.2)TiO3 (PCT) thin films with and without Pb0.8La0.1Ca0.1Ti0.975O3 (PLCT) seed layer were deposited on the Pt(111)/Ti/SiO2/Si substrates by rf magnetron sputtering. The influence of seed layer on microstructures and electric properties of the PCT films was investigated, it was found that the PCT film without seed layer showed random orientation, while the film with seed layer exhibited strong (100) orientation. The PCT thin film with 14nm-thick PLCT seed layer displayed enhanced electrical properties such as a large pyroelectric coefficient (256μC/m2 K) and a low leakage current density (J <2×10−5 A/cm2) at room temperature. The resulting high figure-of-merit (F d =173μC/m2 K) indicates the highly oriented film good candidate for pyroelectric thin-film devices. [Copyright &y& Elsevier]