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Preparation of many amounts of thin film samples with different compositions takes long time. To confirm the possibility of brief and systematic preparation process of oxide films using a chemical solution deposition method, precursor solutions of PbTiO3 and PbZrO3 are synthesized, and those solutions were mixed various volume rate to change the composition of Pb(Zr x Ti1-x)O3 series samples from x=0.1 to 0.9. PbTiO3 and PbZrO3 solutions were mixed just before the film deposition process. The dielectric and ferroelectric properties were evaluated systematically. The relative dielectric constant took a peak around x=0.5. On the other hand, well-saturated P-E hysteresis curves were observed for x=0.3 to 0.9. The remanent polarization and coercive field decreased with increasing Zr content x. These results are consistent with the ferroelectric properties of bulk and film PZT prepared conventional method. Therefore, mixed solution method results in reliable and brief process to discover new oxide mat...

Bi-based perovskite-type oxide materials such as BiFeO3 (BFO) and the related compounds receive much attention and have been developed actively as important candidates for Pb-free ferroelectric / piezoelectric materials instead of toxic Pb-based perovskite oxide materials. Recently, many researches have been reported for thin films of BFO by various film-deposition techniques for actual application of semiconductive devices, microactuators, etc. In this report, we tried preferential crystal growth of BFO films on semiconductive silicon substrates using uniaxial-(100)-oriented LaNiO3 (LNO) buffer layer. BFO films were fabricated via chemical solution deposition (CSD) technique on platinized silicon wafer [(111)Pt/TiO2/(100)Si] and (100)LNO-coated platinized silicon [(100)LNO/(111)Pt/TiO2/(100)Si] substrates. XRD analysis indicated that the films fabricated on (111)Pt/TiO2/(100)Si substrate consisted of randomly-oriented BFO crystal with lower crystallinity and trace amount of the second Bi2Fe4O9 phase. On the other hand, the films on (100)LNO/(111)Pt/TiO2/(100)Si consisted of uniaxial-(100)-oriented BFO crystal with higher crystallinity. The crystallization temperature these films were 450 and 400°C, respectively. These results suggest that the BFO crystal was grown epitaxially on uniaxial oriented (100)LNO plane which also had perovskite-type crystal structure. Consequently, (100)-oriented BFO films were prepared on Si substrate successfully using (100)LNO buffer layer.

A TiNi shape-memory alloy was experimentally manufactured by the vacuum hot pressing method, using pure titanium and nickel powders. The homogeneity and density of the TiNi alloy obtained by this method varies according to the temperature and pressure applied during vacuum hot pressing as well as the holding time. The results of studies of mechanical and physical properties confirmed that the alloys obtained show extremely effective shape-memory characteristics. Thus, it was demonstrated that the TiNi shape-memory alloys can indeed also be produced by the vacuum hot pressing method using elemental titanium and nickel powders.

The strained surface layers of AT-cut quartz plates produced by lapping and polishing have been studied using the X-ray double crystal method. In addition, the influence of surface strain on the characteristics of quartz resonators has been investigated. Experimental results from X-ray double crystal measurements indicate that a residual stress layer in the lapped and polished surface is created and that the quartz resonator performance is also affected.

Bismuth titanate (Bi4Ti3O12; BIT) -based ferroelectric materials are proposed from the view of the “Site-engineering”, where the Bi-site ions are substituted by lanthanoid ions (La3+ and Nd3+) and Ti-site ions by other ions with higher charge valence (V5+). In the present study, influences of vanadium (V) - substitution for (Bi,M)4Ti3O12 thin films [M = lanthanoid] on the ferroelectric properties are evaluated. V-substituted (Bi,M)4Ti3O12 films have been fabricated using a chemical solution deposition (CSD) technique on the (111)Pt/Ti/SiO2/(100)Si substrate. Remnant polarization of (Bi,La)4Ti3O12 and (Bi,Nd)4Ti3O12 films has been improved by the V-substitution independent of the coercive field. The processing temperature of BLT and BNT films could also be lowered by the V-substitution.