Fine pitch hybrid bonding is evolving as a vital advanced permanent bonding in 3D IC technology for its low cost and providing shorter global interconnect length. Chemical mechanical planarization (CMP) is a critical process step for realizing uniform Cu dishing control all over the wafer for successful W2W hybrid bonding. In this paper, we have investigated the effect of various CMP conditions using a three-step CMP process, on Cu dishing, intra-die oxide planarity, and surface roughness and have attempted to understand the dishing control mechanism for our developed CMP process. Atomic force microscopy has been used to characterize the dishing and non-uniformity of the wafers. We have demonstrated controlled dishing