PECVD Low-k (∼2.7) dielectric SiCOH film development and integration for 65 nm CMOS devices

Abstract

This paper describes the optimization of Plasma Enhanced Chemical Vapor Deposition (PECVD) low dielectric constant SiCOH films implemented in 65nm CMOS devices ground rules. The SiCOH film properties were optimized for high mechanical strength and low cracking velocity while maintaining with low dielectric constant in the range of k=2.7-2.8. The integration results were comparable to those of the current first-generation SiCOH film (k ∼ 3.0) integration. The film structure analysis showed that the films contain a high level of cross-linked bonding which attributed to its improved mechanical strength. The improved mechanical film properties allowed its implementation into 65nm Cu/low-k BEOL using the 90nm process integration scheme, while maintaining ULSI chip reliability. © 2006 Materials Research Society.