Silicon dioxide chemical mechanical polishing

Choi W, Lee S-M, Singh R. Further investigation of effects of ph on silicon dioxide chemical mechanical polishing (CMP). The Electrochemical Society 204th Meeting 2003. 

Metal-RIE process was/is used in the fabrication of Al inter-coimects on chips." This process is depicted in four steps in Fig. 2. The first step in the metal-RIE process is sputter deposition of a blanket thin film of Al (or Al alloys, such as Al-Cu, Al-Si) over a planerized dielectric (e.g., silicon dioxide). In the next step, the unwanted metal is etched away by reactive ion etching (RIE) through a photoresist mask. The features produced this way are separated, electrically isolated, metal Al conductor lines. In the RIE process chemicaly active ions such as F or Cl bombard the Al surface and form volatile aluminum fluorides or chlorides, which are then pumped away in the vacuum system. After etcliing, a dielectric is deposited in such a fashion that it fills the gaps between the lines as well as above them. In the last step, the dielectric is planarized using the chemical mechanical polishing (CMP) technique. ... 

Dandu, P.R.V., Penta, N.K., Babu, S.V., 2010d. Novel alpha-amine-functionalized silica-based dispersions for selectively pohshing poly silicon and Si(lOO) over silicon dioxide, silicon nitride or copper during chemical mechanical polishing. Colloids Surf. A 371 (1—3), 131-136. 

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