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Epitaxial Sr-excess SrTiO3 (ST) thin film (Sr/Ti = 1.41) was grown on ST(001) and ST(101) single-crystal substrates using dynamic aurora pulsed laser deposition (PLD) under a 200mT magnetic field. The films spontaneously formed a superlattice structure comprising two layers having different concentrations of Ruddlesden­Popper (RP) planar faults. The superlattice periods of Sr-excess ST thin films deposited on ST(001) and ST(101) substrate were, respectively, 35 and 23 nm. For thin film deposited on ST(001), the in-plane lattice parameter coincided with the substrate, showing coherent growth. For thin film deposited on ST(101), coherent growth occurred along a direction «45° declined against the substrate. The spontaneously formed superlattice was brought about by “up-hill diffusion” of spinodal decomposition. The direction of propagation of the composition wave of spinodal decomposition was regarded as perpendicular to the substrate and «45° declined against the substrate for thin films deposited respectively on ST(001) and ST(101). The superlattice period of the pffiffi thin film deposited on ST(101) (23 nm) is smaller by a factor of 1= 2 than that deposited on ST(001). This relation is explainable by the difference of the propagation direction of the composition wave. The thin film deposited on ST(001) is distorted tetragonally, whereas that on ST(101) is cubic. The Sr-excess ST thin film was also deposited on La-doped ST(101) (La-ST(101)) and La-ST(101) substrates to measure electrical properties. No change was found in the crystal structure and microstructure, irrespective of La-doping. The thin film deposited on La-ST(001) showed ferroelectricity. However, the film deposited on La-ST(101) shows no ferroelectricity. The difference of electrical properties is brought about by differences of crystal symmetry. The difference is also explainable from the perspective of thermodynamic phenomenology.

Pulsed laser deposition (PLD) with an electromagnet (dynamic aurora PLD) and reflection high-energy electron diffraction (RHEED) was developed by installing an 11-tuned solenoid coil in a vacuum chamber. This method achieved thin film deposition under a magnetic field of up to 120 mT using dc current of 1,200 A. The electro- magnet is a solenoid coil, which produces a magnetic field that is proportional to an electric field without saturation of the magnetic field. This PLD method enables in situ observation of the crystal structure of the thin film surface after turning the electromagnet off, but without breaking vacuum. Many reports have described studies of PLD in a magnetic field. For most such studies, permanent magnets have been used to apply a magnetic field to the plume. Nevertheless, when doing so, carrying out in-situ observation using RHEED is difficult because the magnetic field deflects the electron beam. This case study examined effects of magnetic field application to the plume on the in-plane orientation and resistivity of a NiO thin film deposited on a MgO(001) single crystal at room temperature (25 °C). Results demonstrate that the in-plane orientation (epitaxial growth) is unchanged, whereas thin film resistivity decreases exponentially with the magnetic field intensity during deposition. These results suggest that the Ni3+ ion concentration can be expected to increase exponentially with the magnetic field during deposition. The room-temperature resistivity of the NiO thin film deposited under a 120 mT magnetic field was 112 ohm cm.

Polycrystalline ZnFe2O4 thin films were deposited on Si and porous Si (PSi) substrates using Dynamic Aurora pulsed laser deposition (PLD in a magnetic field). The average grain sizes of ZnFe2O4/Si and ZnFe2O4/PSi were, respectively, 120 and 48 nm. The ZnFe2O4/PSi thin film resistance was higher than that of ZnFe2O4/Si thin film. For ZnFe2O4/Si and ZnFe2O4/PSi thin films, the sensor response for liquefied petroleum gas was measured as a function of time and temperature. The sensor response of ZnFe2O4/PSi thin film measured at 375 °C is higher than that of ZnFe2O4/Si thin film. Results showed a steep initial rise in the temperature dependence of ZnFe2O4 thin films prepared using PLD. The dependence is steeper than that reported for ZnFe2O4 powder or thick and thin films prepared using chemical processing.

Al2O3 thin films were deposited on (001)Si substrate through Cr2O3/yttria-stabilized-zirconia (YSZ) buffer layer by cold-wall type chemical vapor deposition method with tri-methyl aluminum as a raw material. By changing the deposition temperature, different polytypes of Al2O3 thin films were formed. At lower temperatures (1123–1173 K), η-Al2O3 and amorphous Al2O3 were found in mixture. With increasing the deposition temperature, the series of Al2O3 polytypes (γ, κ and α) appeared in the order of decreasing the unit cell volume per Al atom. At 1323 K, single-phase α-Al2O3 thin film was obtained in success. On (00l)Cr2O3/YSZ/Si substrate, epitaxial (00l)α-Al2O3 thin-film was grown, however, on (00l)YSZ/Si substrate, epitaxial (00l)κ-Al2O3 thin film was formed. It shows that buffer layer also has much influence on polytype of Al2O3 thin film. On the other hand, there exist the polycrystalline α-Al2O3 and Cr2O3 have the same Miller index (h k l), therefore, polycrystalline α-Al2O3 thin film was deposited on the polycrystalline Cr2O3 buffer layer in which each Al2O3 and Cr2O3 grain has an epitaxial relation. This epitaxial growth can be explained by both the similarity in crystal structure between Al2O3 film and Cr2O3 buffer layer, and also their moderate lattice mismatch.