In order to study anode effects in Cu electroplating, we investigated the characteristics of the Cu films electrodeposited on Cu seed layer and the surface change of anodes, by using Cu (soluble) and Pt (insoluble) anodes. For the case of Cu anode, the brownish passivation layer was formed on the surface of Cu anode, and this was mainly composed of by-products which was formed by reaction of impurities in electrolyte with copper anode. In use of Pt anode, the O 2 bubbles on the anode surface were occurred. The current density in bath for the case of Cu anode was larger than that of Pt anode and increased after 300 s of plating time had elapsed. In formation of the electroplated Cu films, the deposition rate of Cu films electroplated by using Cu anode was larger and the density of film plated by using Cu anode was higher than those by Pt anode.

In order to remove native Cu oxides formed on Cu seed layer, TS-40A and H 2 SO 4 solutions were used. After various pretreatments, the changed surface of Cu seed layer was estimated by SEM and XPS. For all pretreatments, the mass of samples was decreased. The mass loss of sample treated in H 2 SO 4 solution for 60 s was the largest. After TS-40A pretreatment, native Cu oxide layer is not at all removed although the carbon on Cu seed layer was removed mainly with a few loss of sample mass. By H 2 SO 4 treatment after TS-40A pretreatment, most of native Cu oxides on Cu seed layer were removed with a lot of mass loss and the oxides will be eliminated by control of dipping time. Consequently, we found that the pretreatment by H 2 SO 4 is suitable to obtain a Cu seed layer removed native oxide for electrodeposition

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An interpoly-stacked dielectric film with a SiO2/Si3N4/SiO2/Si (ONO) structure was prepared via the atomic-layer deposition method. The multilayer structure of the ONO film with triple interfaces was investigated via medium-energy ion scattering (MEIS). A few defects in the interface layer of the ONO structure were detected. From the X-ray photoelectron spectroscopy (XPS) results, it was presumed that the interface layer with defects in the MEIS result is due to the formation of an oxynitride layer on the unstable and rougher Si3N4 layer via. By measuring the I-V characteristics, the leakage current density and breakdown field of the ONO film were determined to be 3.4 x 10(-9) A/cm2 and 10.86 MV/cm, respectively. By estimation the C-V curve, the flat band (V(FB)) of the ONO film shifted to a negative voltage (-1.14 V), the dielectric constant (K(ONO)) of the ONO film was 5.79, and the effective interface-trapped charge density of the ONO film was about 4.96 x 10(11)/cm2.