Effects of the conventional bath additives ͓chloride ions ͑Cl − ͒, poly͑ethylene glycol͒ ͑PEG͒, bis͑3-sulfopropyl͒disulfide ͑SPS͒, and Janus green B ͑JGB͔͒ used in the damascene process on the filling of submicrometer trenches with electrodeposited copper were investigated by electrochemical polarization measurement and cross-sectional microscopy. The combination of Cl − and PEG inhibited copper deposition in the areas of opening of the trenches, while SPS accelerated it at the bottom. Polarization curves showed that the degree of acceleration of copper deposition by SPS increases with the concentration of SPS. This SPS concentration-dependent acceleration accounts for the observed bottom-up growth. The addition of JGB inhibited copper deposition at the later stages of the filling process, leading to the suppression of the overfill phenomenon, although the bottom-up growth was also inhibited at high JGB concentrations. Bath agitation significantly enhanced the inhibition effect of JGB on the overfill phenomenon, without disturbing the bottom-up growth.

In conjunction with a study of the copper electrodeposition process from the acid copper sulfate bath for the fabrication of interconnections of printed circuit boards and semiconductor devices, an investigation was performed of the effect of bath additives on the relationship between the ductility of the copper deposit and its crystallographic structure and electrical resistivity. Room-temperature recrystallization, or so-called self-annealing, is known to occur in copper electrodeposits obtained from baths containing Cl − , polyethylene glycol, and bis͑3-sulfopropyl͒disulfide as additives. Variation with time of the crystallographic orientation, grain size, and resistivity of the deposit was followed over a period of several weeks after the deposition. During the period of self-annealing, ductility was found to increase by a factor of 1.5. The increase in ductility is shown to be related to a change in microstructure of the copper deposit.

ABSTRACT:The aluminum aryloxide was prepared via the reaction of phenolic antioxidant, 3-(3,5-di-t-butyl-4-hydroxyphenyl)-N-octadecylpropionamide, with triethyl aluminum. Propylene polymerization using supported ZieglerNatta catalyst systems was carried out in the presence of the antioxidant or its aluminum aryloxide. Although the antioxidant gave rise to decrease in catalyst yield and change in hydrogen response, the aluminum aryloxide had no influence on the catalytic polymerization behavior, and thus the obtained polymer characteristics such as molecular weight, polydispersity, and meso pentad as a stereoregularity were comparable to that polymerized without the antioxidant and the aluminum aryloxide. Polypropylene obtained in the presence of the aluminum aryloxide was well stabilized for oxidation and its stability was over 1000 h at 100°C (estimated to be over 30 years at room temperature).

Copper films electrodeposited from acid sulfate baths containing conventional additives used in the damascene process for the fabrication of ultralarge-scale integration interconnects were analyzed quantitatively to investigate the relation between carbon content and electrical resistivity of the deposit. In the as-deposited state, the resistivity of deposits that did not exhibit selfannealing effects in scanning ion microscope examination increased almost linearly with carbon content in the range of 0.002-0.045 wt %. The deposits that exhibited self-annealing effects showed higher resistivity values at identical carbon contents. After self-annealing, resistivity values of all deposits varied almost linearly with carbon content.

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