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Abstract − RC delay is a critical issue for achieving high performance of ULSI devices. In order to minimize
the RC delay time, we uses the CMP process to introduce high-conductivity Cu and low-k materials on the damascene. The low-k materials are generally soft and fragile, resulting in structure collapse during the conventional
high-pressure CMP process. One troubleshooting method is electrochemical mechanical polishing (ECMP)
which has the advantages of high removal rate, and low polishing pressure, resulting in a well-polished surface
because of high removal rate, low polishing pressure, and well-polished surface, due to the electrochemical acceleration of the copper dissolution. This study analyzes an electrochemical state (active, passive, transpassive state)
on a potentiodynamic curve using a three-electrode cell consisting of a working electrode (WE), counter electrode (CE), and reference electrode (RE) in a potentiostat to verify an electrochemical removal mechanism. This
study also tries to find optimum conditions for ECMP through experimentation. Furthermore, during the lowpressure ECMP process, we investigate the effect of current density on surface roughness and removal rate
through anodic oxidation, dissolution, and reaction with a chelating agent. In addition, according to the Faraday’s
law, as the current density increases, the amount of oxidized and dissolved copper increases. Finally, we confirm
that the surface roughness improves with polishing time, and the current decreases in this process
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