Y2O3 nanosheets as slurry abrasives for chemical-mechanical planarization of copper

Abstract

Continued reduction in feature dimension in integrated circuits demands high degree of flatness after chemical mechanical polishing. Here we report using new yttrium oxide (Y 2 O 3 ) nanosheets as slurry abrasives for chemical-mechanical planarization (CMP) of copper. Results showed that the global planarization was improved by 30% using a slurry containing Y 2 O 3 nanosheets in comparison with a standard industrial slurry. During CMP, the two-dimensional square shaped Y 2 O 3 nanosheet is believed to induce the low friction, the better rheological performance, and the laminar flow leading to the decrease in the within-wafer-non-uniformity, surface roughness, as well as dishing. The application of the two-dimensional nanosheets as abrasive in CMP would increase the manufacturing yield of integrated circuits.

2D-nanomaterials for controlling friction and wear at interfaces

“…These include materials such as phosphates and layered oxides. Recently, Liang and co-workers have explored the use of Zr phosphate nano-platelets and yttrium oxide nanosheets (Y 2 O 3 ) as additives for lubricants as well as abrasive additives for processes such as chemomechanical planarization [79,80]. As with many of the above describe platelet systems, the Zr phosphate nano-platelets (on the order of 30 nm in thickness and 600-1000 nm in length) can be incorporated into oil or water based lubricants as an additive with loadings ranging from 0.0004 wt% to 0.5 wt%, which showed decreases in friction from anywhere from 65% to 91% (Fig.…”

Chemical mechanical polishing of steel substrate using colloidal silica-based slurries

“…As an ultra-precision processing technique, chemical mechanical polishing (CMP) technique has been widely used in semiconductor fabrication. CMP combines the synergistic effect of chemical etching and mechanical abrasion, and can achieve both local and global planarization of the substrate surface [14][15][16][17]. Recently, the application of CMP technique has been extended to other areas, such as high value-added and precise instruments.…”

Tribo‐electrochemical study of stainless steel surfaces during chemical–mechanical polishing

“…Nevertheless, in some applications tribocorrosion can be conveniently exploited for surface finishing purposes, such as in the case of chemical–mechanical polishing (CMP) process. As an ultra‐precision technique, CMP has been widely used in manufacturing of integrated circuits (IC) for achieving local and global planarity . In the CMP process, the suspended abrasive particles can cause the detachment of surface layers formed by reaction between the oxidising aqueous suspension (the slurry) and the material to be polished .…”

“…As an ultra-precision technique, CMP has been widely used in manufacturing of integrated circuits (IC) for achieving local and global planarity. 2 In the CMP process, the suspended abrasive particles can cause the detachment of surface layers formed by reaction between the oxidising aqueous suspension (the slurry) and the material to be polished. 3,4 Therefore, the CMP process combines the synergistic effect of chemical etching and mechanical abrasion to achieve surface planarisation.…”