SrRuO3 films were grown on (001)SrTiO3 single crystal substrates by rf magnetron sputtering under various total pressures, and their crystal structure, room temperature resistivity, and temperature dependency of resistivity were investigated. High-resolution X-ray diffraction (XRD) analysis revealed that the unit cell volume of these films decreased with increasing total pressure from 1.3 to 27 Pa and was almost constant above 27 Pa corresponding to that of bulk SrRuO3. SrRuO3 films deposited under a total pressure of 27 Pa showed the lowest room temperature resistivity, i.e., 250 µΩ·cm, almost the same as the reported one of the SrRuO3 single crystal. This film also showed a positive temperature dependency of resistivity with a temperature dependency change at about 150 K, which was also in good agreement with the reported one of the SrRuO3 single crystal.

Raman spectra from Ga1−xInxAs epitaxial layers of various compositions were studied. Both disorder-activated acoustic and optical phonons appeared in the midrange of composition independent of substrate materials. Broadening in the LO phonon due to stress was also observed near the interface region between the epitaxial layer and the substrate when there was lattice mismatch between them even if the amount was as small as 0.7%.

We have investigated polarized Raman spectra of (001)/(100)-oriented tetragonal epitaxial Pb(ZrxTi1−x)O3 (PZT) thin films (x=∼0.35) in which the volume fraction of the polar c domain is systematically varied from 4% to 96%. From polarization analyses using high epitaxial quality films, we have successfully isolated the A1 and B1 phonons from the E phonons, thus offering a distinctive evaluation of the c domains. As increasing c-domain volume, the A1(TO) modes linearly increase in their intensity. A remarkable correlation is found between the A1(1TO)-mode intensity and the c-domain volume for PZT films. We suggest that this correlation as well as the A1(1TO)-mode intensity provide a simple and useful probe for characterization of c-domain volume and ferroelectric properties in PZT-based devices.

Investigations of defects are important to understand the properties of zinc oxide (ZnO), especially oxygen vacancies, which are intrinsic defects that are easily generated during crystal growth or device processing. In this study, we evaluate the oxygen vacancies in ZnO single crystals and powders using micro-Raman spectroscopy. Reducing ZnO in a hydrogen atmosphere at 400 600°C for 30240 min changes the amount of oxygen vacancies. Raman spectroscopy reveals a slight shift and a decrease in the E 2 (high) phonon mode, which is related to the oxide ion vibration. The peak position of the E 2 (high) mode shifts toward a lower frequency and the peak intensity decreases as the oxygen vacancies increase. This behavior can be explained by the existence of oxygen vacancies in ZnO. Because the E 2 (high) peak shift and the intensity are scaled in accordance with the amount of oxygen vacancies, these correlations offer a simple and useful probe to evaluate oxygen vacancies in ZnO.