The Impact from the Titanium under Layer Film Thickness and the Thermal Budget Stress Generating Abnormal Aluminum Grains and Partial Voids in the Metal-1 Interconnect Lines

摘要

Metal defectivity has become one of the most important issues for morphological and electrical characterization for 0.13um flash technology, especially for integration problems among metal deposition, photolithography definition, and etching. In this work we focused our attention on two kind of defects. Rough metal strips and partial voiding of metal lines (holes). In particular the influences of Titanium layer thickness for the metal-1 interconnect lines and the wafer thermal stresses on deposited metal lines were evaluated. All wafers were screened by different defectivity tools. SEM and TEM micrographs were analyzed in detail for understanding of critical features. Moreover the impact from each variable on the total defect counts was estimated.