ZnO films were grown by metalorganic chemical vapor deposition using the repeated temperature modulation in an H2 ambient. The crystalline quality, as defined by the full-width at half-maximum of the ω (101¯1) reflection, was found to be correlated with the photoluminescence (PL) lifetime at 300 K. The fine structure of the PL spectra for the samples grown under Zn-rich condition at 8 K indicated the higher order (n=2) structure of free exciton A, two electron satellites and phonon-replicas. The internal quantum efficiency and the PL lifetime at 300 K were 5.5% and 2.6 ns, respectively, indicating a reduction in Zn vacancies in the ZnO films.

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ZnO films were fabricated by metalorganic chemical vapor deposition while a laser substrate heating system was used to rapidly cycle the sample temperature. When a hydrogen gas atmosphere was used together with the temperature modulation, ZnO films deposited from diethyl-zinc and oxygen exhibited oxygen-face polarity and a smooth surface. The quality of ZnO films was good enough to observe phonon replicas corresponding to the transition from donor-bound to free exciton in the temperature dependence of photoluminescence. The growth of ZnO film is discussed in relation to the combined effect of growth temperature modulation and the hydrogen atmosphere.

We have fabricated all YBa2Cu3O7−δ (YBaCuO) trilayer junctions with YBaCuO wiring layers using CeO2 insulating layers. The trilayer junctions consist of YBaCuO/PrBa2Cu3O7−δ (PrBaCuO)/YBaCuO structures on (100) MgO substrate. Both YBaCuO wiring layer and base-YBaCuO electrode have the critical temperature Tc of ⩾87 K. A 5×5-μm2 junction with a PrBaCuO barrier thickness of 25 nm shows a resistively-shunted-junction (RSJ)-like current–voltage (I–V) characteristic with a critical current density Jc of 1.7×102 A/cm2 and a critical current×normal resistance (IcRn) product of 0.40 mV, and no contact resistance at 4.2 K. The magnetic field dependence of Ic for the junction shows a Fraunhofer interference pattern with a modulation period of 3.5 mT, which is in good agreement with the value estimated from the junction size of 5 μm. In addition, the YBaCuO wiring layers have no structures in the I–V characteristics due to grain–boundary junctions. These facts confirm that the observed Josephson properties come from the YBaCuO/PrBaCuO/YBaCuO trilayer structure.