Chemical mechanical polishing (CMP) has emerged as a time, materials, and cost effective solution for providing the planar dielectric 1-3 and metal 4-8 layers necessary for the fabrication of sub-0.25 m interconnects. Present integrated circuit (IC) interconnects use aluminum lines, tungsten vias, and oxide interlevel dielectrics (ILDs). Advanced structures use copper lines and vias with low dielectric constant (low-) ILDs. Copper metal provides faster signal transfer and enhanced interconnect lifetime and low-ILDs (2.0 < < 3.0) reduce signal delay and cross-talk capacitance. [9][10][11] The fabrication of copper and low-interconnects requires copper patterning by damascene CMP. The single damascene process includes etching trenches or contact holes (vias) into the dielectric, filling these trenches with liner/barrier and metal, and removing the undesired metal from field regions using CMP. 12 Several papers have demonstrated the successful integration of both Al and Cu metals with low-dielectrics using damascene CMP. [13][14][15][16][17] In many strategies for damascene patterning, a hardmask or etch stop comprises the top tenth to fifth of the dielectric thickness to protect the dielectric from dry and wet etch chemistries. This hardmask, often silicon nitride or silicon oxide, has a higher dielectric constant (high-, 4.0 < < 7.0 ) than the low-material, resulting in a higher effective dielectric constant for the ILD stack. The CMP scheme illustrated in Fig. 1 allows the lowest capacitance from Cu/low-integration. The desired process requires removal of the copper metal overburden followed by removal of liner/hardmask materials from the dielectric surface. Processing in this manner results in direct CMP of the low-dielectric during the overpolishing required to ensure that all copper, barrier, and hardmask are completely removed.Polymeric and porous low-alternatives are, in general, not as strong physically as SiO 2 , although they are very stable chemically. Reduced physical strength and increased chemical resistance lead to challenges during CMP. The currently accepted mechanism for CMP is chemical alteration of a material surface followed by mechanical abrasion and removal. If relatively high-polish stops are to be polished away, the same slurry used for copper and barrier removal will contact the underlying polymer. Understanding the physical and chemical alteration of the low-material surface during copper CMP is of particular importance for creating electrically, thermally, chemically, and physically stable copper/low-interconnect structures. This information is of increasing importance for future technologies, particularly as minimum feature sizes go below 100 nm.The CMP of polyimide, 18 parylene-n, 19-21 BCB, 19-23 SiLK TM , 22,23 and FLARE TM 24 has been examined previously, in both damascene patterning and direct planarization strategies. The present work compares the CMP of BCB ( ϳ 2.65) and SiLK ( ϳ 2.65) polymer thin films in slurries developed for copper CMP. The effects of slurry chemistry and ab...