Low-damage damascene patterning of SiOC(H) low-k dielectrics

Etch and strip plasma-induced damage is well-known to make the integration of sensitive low-k dielectrics in damascene schemes cumbersome. In this paper, three metal hardmask-based single-damascene patterning approaches are compared. EFTEM analysis and integrated k-value extraction show that the use of a metal hardmask-based scheme with optimized plasma chemistries and etch/strip sequencing results in very low damage to the SiOC(H) low-k dielectric.