Thin films of (La,Sr)MnO 3 (LSMO) were deposited on ZnO underlayer on sapphire (Sap) substrate by ion beam sputtering at the growth temperatures from 650˚C to 750˚C with supply of either plasma oxygen or molecular oxygen. The epitaxial relationships of lattices and crystalline qualities of LSMO/ZnO/Sap double-hetero systems were extensively analyzed by means of X-ray diffraction techniques with a modern high resolution XRD system. The epitaxial growth of out-of-plane (110) phase of the LSMO overlayer on the (0001) ZnO underlayer on the (0001) sapphire substrate is promoted at the higher temperatures accompanying the suppression of other competitive growth of the LSMO (001) and (111) phases. The plasma oxygen supply more enhances this suppression of the LSMO (111) phase at 750˚C. The complex in-plane orientational relationships of these three phases were clarified by the precise analyses based on various measurements of high resolution out-of-plane XRD and in-plane XRD, pole figure, and reciprocal space mappings. They are summarized as follows. (111) phase were discussed. These relationships were confirmed also by the data analyses of out-of-plane wide-range reciprocal space mappings using the 2-dimensional X-ray detector.

Poly(ethylene terephthalate) (PET) films can be bonded directly by oxygen plasma irradiation and heat press at low temperatures of 100–160 °C. The irradiated films were kept in the atmosphere for six years, yet they can be bonded tightly. The irradiated surface is extremely active just after the irradiation, and it is considerably active after five years. Dry- and wet-peel tests suggest hydrogen bonding and chemical bonding. The films are bonded by these two elements at lower press temperatures, while by the pure chemical bonding at higher temperatures. Fourier transform infrared spectroscopy (FTIR) results on the non-irradiated, irradiated and bonded samples indicate that OH and COOH groups are created at the surface, they are responsible for the both bondings. Dehydrated condensation reaction is proposed for the chemical bonding. The hydrogen bonding is broken by water penetration, causing smaller peel strength under the wet-peel test. Cross-linking layer may be the origin for the long lifetime.

Biaxially oriented polyethylene terephthalate (PET) films can be bonded directly by oxygen plasma irradiation and low temperature heat press around 100°C. The irradiated films were kept in the atmosphere for six years, yet they can be bonded tightly as well. Dry-and wetpeel tests indicate that two bonding elements can be suggested, hydrogen bonding and chemical bonding. The films are bonded by these two elements at lower temperatures, but by the pure chemical bonding at higher temperatures. FTIR results on the non-irradiated, irradiated and bonded samples indicate that OH and COOH groups are created at the surface, they are responsible for the hydrogen and chemical bondings. Dehydrated condensation reaction is proposed for the chemical bonding. It is briefly mentioned on two origins for the long lifetime of irradiated active surface.

In this article it is reviewed on enigmatic electrical and magnetic properties of La(Ba)Mn0 3 thin films, useful for tunable microwave filters. As-grown films have well separated insulating to metallic (Tp) and paramagnetic to ferromagnetic (Tc) transition temperatures, which can be understood from the phase separation model. The film shows negative magnetoresistance (MR) caused by normal double exchange coupling effect, and positive MR which is interpreted by a magnetostriction effect. The phase separation is caused by crystal strain in the film. By annealing these two temperatures, Tp and Tc, become more separated, implying a size reduction of ferromagnetic grains. The phase separation scenario can be confirmed by ferromagnetic resonance (FMR) showing doublet signals. The FMR indicates anisotropic phase transition which supports the magnetostriction model. Moreover, the narrow FMR signals suggest high spin ordering and good crystallinity.

Hetero double-layers of LaBaMnO 3 (LBMO)/ZnO were fabricated by ion beam sputtering on substrates of MgO, sapphire (SP), LaAlO 3 (LAO), and SrTiO 3 (STO). All the surfaces of substrates, ZnO and LBMO have step-terrace morphology. The p-LBMO/n-ZnO/SP shows junction rectification at different temperatures. The junction resistance follows from colossal magnetoresistance (CMR) of LBMO based on DEC model. The different LBMO/ZnO junctions on the different substrates show different junction behaviors at room temperatures. LBMO/ZnO/STO has the largest rectification factor of 210. After running measurement currents, LBMO/ZnO/STO shows current-voltage (I-V) switchings. LBMO/ZnO/MgO shows very clear switching and large hysteresis between upward and downward voltage sweeps. These are interpreted by CMR and DEC model, and phase separation. The switching is caused by disconnection of percolation path consisting of ferromagnetic metallic grains. The higher resistant state cannot be quickly transformed back to the lower resistant state during the downward sweep.

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In this article it is reviewed on enigmatic electrical and magnetic properties of La(Ba)MnO 3 thin films, useful for tunable microwave filters. As-grown films have well separated insulating to metallic (T p ) and paramagnetic to ferromagnetic (T c ) transition temperatures, which can be understood from the phase separation model. The film shows negative magnetoresistance (MR) caused by normal double exchange coupling effect, and positive MR which is interpreted by a magnetostriction effect. The phase separation is caused by crystal strain in the film. By annealing these two temperatures, T p and T c , become more separated, implying a size reduction of ferromagnetic grains. The phase separation scenario can be confirmed by ferromagnetic resonance (FMR) showing doublet signals. The FMR indicates anisotropic phase transition which supports the magnetostriction model. Moreover, the narrow FMR signals suggest high spin ordering and good crystallinity.