Secondary ion mass spectrometry (SIMS) and work function measurements were made to examine the surface composition difference between Bi2Sr2CaCu2O8 surfaces that were cleaved at low temperature and at room temperature. SIMS measurements of the surfaces cleaved at room temperature indicated that the intensity of secondary ions Ca+, Sr+, and Cu+ increases and the intensity of O– decreases with time. More‐ over, the work function increased with time. On the other hand, SIMS of the surfaces cleaved at low temperature indicated comparatively much smaller changes in intensity of secondary ion spectra and work function. These findings are discussed in terms of the decrease in surface oxygen content, and the effectiveness of the cleavage at low temperature is clarified. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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We investigated the effectiveness of using argon gas with added nitrogen when filling deep sub-mm through-holes with copper by high-vacuum planar magnetron sputtering, and we examined the optimum amount of added nitrogen. This is done by varying the amount of added nitrogen between 0.5, 1.0, 3.0, 10, and 20 at. % in copper filling experiments conducted at a substrate temperature of 280 C and a gas pressure of p ¼ 9:0 Â 10 À2 Pa with 80-nm-diameter holes having an aspect ratio of 5.6. The results show that the optimal amount of added nitrogen for copper filling is 1.0 at. %, and that the proportion of conformal filling is 1/5. The reasons for this are discussed in terms of the energy relationship between copper atoms adsorbed physically or chemically by nitrogen, sputtered atoms, and recoil atoms or molecules.

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