Investigation of Co surface reaction by in situ measurement for chemical mechanical planarization and post-chemical mechanical planarization cleaning

Abstract

Co is one of the candidates for a new material in the advanced generation of LSI. However, it is difficult to implement a precise analysis of surface reactions because a Co surface is unstable. In chemical mechanical planarization (CMP) and post-CMP cleaning, many surface reactions are simultaneously induced such as dissolving Co by a chelating agent, adhesion of an inhibitor, and oxidation of a Co surface. Those reactions should be controlled to establish the ideal processes of CMP and post-CMP cleaning. In this work, we performed open circuit potential (OCP) monitoring and succeeded in tracing the complicated reactions. It enabled us to compare the strengths of inhibitors and select appropriate inhibitors in a post-CMP cleaner. The measurement and analysis can be applied to not only post-CMP cleaning but also CMP.

Preparation and characterization of Ni–TiN nanocomposites prefabricated by jet pulse electrodeposition

“…This resulted in the formation of smaller grains in the composite. 14) Second, as jet rate rose, the higher kinetic energy of the plating solution dislodged weakly adsorbed TiN nanoparticles from the composite surface into the solution. This reduced the fine-grain effect of TiN nanoparticles, further increasing the size of numerous nickel nuclei and the R a of the Ni-TiN nanocomposite.…”

Adsorption Mechanism of Potassium Oleate on Cobalt Surface Based on Cobalt Interconnection CMP: A Combined Experimental and DFT Investigation

“…An important aspect of metal interconnect polishing is to protect the concave area of wafer surface from corrosion while the convex part is removed selectively. 7,8 BTA [9][10][11] was widely used for CMP and post CMP cleaning as a corrosion inhibitor, [12][13][14] which can effectively decrease the corrosion of the concave area on cobalt wafer surface. Lu et al 15 studied that the material removal rate (MRR) and static etching rate (SER) of Co decreased significantly with the increase of BTA concentration under an acid environment.…”