METAL-CONTAMINATION -FREE THROUGH-SUBSTRATE VIA STRUCTURE

摘要

A through-substrate via (TSV) structure that is immune to metal contamination due to a backside planarization process is provided. After forming a through-substrate via (TSV) trench, a diffusion barrier liner is conformally deposited on the sidewalls of the TSV trench. A dielectric liner is formed by depositing a dielectric material on vertical portions of the diffusion barrier liner. A metallic conductive via structure is formed by subsequently filling the TSV trench. Horizontal portions of the diffusion barrier liner are removed. The diffusion barrier liner protects the semiconductor material of the substrate during the backside planarization by blocking residual metallic material originating from the metallic conductive via structure from entering into the semiconductor material of the substrate, thereby protecting the semiconductor devices within the substrate from metallic contamination.