The effects of α-sodium alkenesulfonate and alkylphenol polyoxyethylene ether phosphate on the inhibition of copper chemical mechanical polishing

In this work, α-sodium alkene sulfonate (α-AOS) and alkylphenol polyoxyethylene ether phosphate (APE-10P) were tested as environmentally friendly inhibitors in slurries to replace toxic benzotriazole. α-AOS and APE-10P can improve slurry dispersion, increase the inhibition efficiency to 79.6 % and polishing rate reduced to 8414 Å/min; Reduced corrosion and surface roughness decreased from 3.10 nm to 1.41 nm; By measuring the particle size of polishing solution, it has been proven that the addition of two active agents effectively improves the dispersion of the solution, reduces the distance between silica sol colloids, and reduces the particle size of silica sol from 71.5 nm to 68.5 nm; To verify the stability of the polishing solution, the Zeta potential of the polishing solution on the first day was −40.99 mV, and on the seventh day it was −36.6 mV, which can meet the stability requirements for at least seven days and meet industrial requirements. Calculation proves that APE-10P and α-AOS can spontaneously adsorb on Cu surfaces. This work focuses on the mechanism of inhibition in Cu CMP, which provides some inspirations for the development of environmentally friendly slurries.