In order to enhance an etching rate using a conventional rf sputtering system, sputtering gases of fluoro-chloro-hydro-carbon were examined, the compositions of which were CF4, CCl2F2, CCl3F, CHCl2F, CHClF2, (CCl2F)2, CCl2FCClF2, and (CBrF2)2. Etching specimens were Si, quartz, glass, Al, Mo, stainless steel and photo resist. With the rf power density of 1.3 W/cm2 at the etching table, the etching rate of Si was ranged from 1000 to 2000 Å/min, which were ten to twenty times higher than that by argon. High etching rate is considered to be due the formation of volatile compounds on the surface of specimens. However, etching mechanism is not clarified in detail now. The effect of oxygen on the etching rate was also investigated, and it was found that the etching rate of Si did not decrease up to 12.5% in content of oxygen.

A detection of the stacked integrated Sachs-Wolfe (ISW) signal in the CMB of rare superstructures identified in the SDSS Luminous Red Galaxy catalogue has been reported at very high statistical significance. The magnitude of the observed signal has previously been argued to be more than 3σ larger than the theoretical ΛCDM expectation. However, this calculation was made in the linear approximation, and relied on assumptions that may potentially have caused the ΛCDM expectation to be underestimated. Here we update the theoretical model calculation and compare it with an analysis of ISW maps obtained from N -body simulations of a ΛCDM universe. The differences between model predictions and the map analyses are found to be small and cannot explain the discrepancy with observation, which remains at > 3σ significance. We discuss the cosmological significance of this anomaly and speculate on the potential of alternative models to explain it.

Lead zirconate titanate (PZT) thin films have been prepared with a multi-target sputtering system onto Pt-coated Si substrates. Structure, composition and dielectric properties have been investigated on films ranging in thickness from 60 nm to 1400 nm. The dominant phase of PZT thin films varied from pyrochlore to perovskite with increasing film thickness. An interface PZT layer with about 100 nm thickness, which was confirmed to mainly consist of pyrochlore phase grains, was observed at the PZT/Pt interface in a cross-sectional transmission electron microscopy (TEM) image of an 850 nm thick film. That is, the pyrochlore grains preferentially grow at the early stage of deposition and do not change their structure during subsequent deposition. Dielectric constant and remnant polarization were degraded with decreasing thickness. This can be explained in view of the existence of the interface layer with a low dielectric constant.

Thin films of SiO2 are deposited using tetraethoxysilane (TEOS) as the source gas in remote rf (13.56 MHz) and microwave plasmas. Depositions were carried out using atomic and molecular radicals of different reactivities generated in O2, N2, H2, Ar and He plasmas. SiO2 films could be fabricated only in the downstreams of O2, N2 and Ar plasmas with the reaction of TEOS. SiO2 was not produced by TEOS with the reaction of downstream of H2 or He plasma. SiO2 deposited with Ar plasma contains a small amount of C. The activation energy of film growth rate varies depending on the partially decomposed TEOS precursor density. Furthermore, the quality of SiO2 films deposited with energetically different ground-state ( O(3P)) and excited-state ( O(1D)) atomic oxygen environments was comparatively studied. Films deposited in an excess O(1D) environment show better physical and electrical properties, though the yield of SiO2 is independent of the state of the atom.

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