Chemical Mechanical Polishing(CMP) 공정에서 웨이퍼에 작용하는 압력분포 해석

During the metal Chemical Mechanical Polishing (CMP), the levels of metals (Cu or W) and oxides are reduced, causing surface irregularities. Both line width and pattern density (e.g., line density) influence yield and contribute to the surface variation. The CMP process must be optimized to achieve the best planarity (i.e., flat surface) while improving yield. Erosion reflects the localized loss of oxide level while dishing accounts for the change in metal level when either Cu or W recedes or protrudes above the oxide level, as shown in Figure 1. Dishing and erosion account for a major portion of yield losses and are the critical factors in the CMP process.