Ruthenium dioxide ( RuO2) thin films are evaluated as a bottom electrode for SrTiO3. It was found that a thin RuO2(50 nm)/Ru(20 nm) layer on Si is quite effective as a barrier layer for both orygen atoms and metals when depositing SrTiO3 at a relatively low temperature of 450° C. To test its suitability for high-temperature processes such as CVD of SrTiO3, the RuO2/Ru electrode on Si was annealed in air at 600° C for 1 hour. Even under this severe condition, the electrode using 100-nm-thick RuO2 was sufficient for preventing oxygen diffusion into Si.

A new dual elementary-steps growth mechanism was observed during our research on the CdHg(SCN) 4 (H 6 C 2 OS) 2 (CMTD) crystals. Namely two types of elementary-step sources with different step height can be produced on the same crystal surface during the growth of some crystals. Furthermore the sum of these elementary-step heights is equal to the corresponding interplanar distance d hkl . The heights of these elementary steps were determined by crystal structure as well as growth motif and they have no relation to crystal defects. The elementary steps referred in this paper are completely different to sub-step mentioned by Min in 1988. Only one step height h was included in normal growth rate formulas for the dominant crystal growth theories at present such as BCF spiral growth mechanisms and the classic two-dimensional nuclear growth modes. Without considering the effects of the dual elementary-steps h 1 and h 2 to the growth procedure, the classic formulas containing the parameter h (step height) should be modified when they are applied to the research on crystals growing with dual elementary-steps growth mechanism.

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The effect of in‐situ cooling conditions on surface roughness and superconducting properties have been studied. Bi‐Sr‐Ca‐Cu‐0 thin films were grown in‐situ on (100) MgO substrates at 700°C by activated reactive co‐evaporation. The films cool‐down in 760 Torr oxygen showed a transition temperature (Tc(onset)) of 100 K and zero resistance temperature (Tc (zero)) of 65 K. Smooth surface was obtained for the sample cooled‐down in oxygen plasma.

Ruthenium dioxide (RuO2) thin films are evaluated as bottom electrode for dielectric SrTiO3. It was found that a RuO2 (50nm) / Ru (20nm) barrier layer on a Si substrate is effective as an oxygen barrier layer and as a metal diffusion barrier layer for sputter deposited SrTiO3 films at substrate temperature of 450°C. To test suitability for high temperature processes, RuO2/Ru electrodes were annealed in air at 600°C. 100nm-thiick RuO2 was sufficient to prevent oxygen diffusion. After annealing in the same condition, the leakage current of sputter deposited SrTiO3 (150nm) on RuO2(50nm) / Ru(50nm) was 7.6 × 10 −9 (A/cm2) at 2V.