Detection of Electrical Defects by Distinguish Methodology Using an Advanced E-Beam Inspection System

Abstract

With critical dimension shrinks during semiconductor process development, E-beam inspection (EBI) technique has play a vital role in detecting inline electrical defect by voltage contrast (VC). This study we introduce three different defect monitoring for 28nm process. The first is Cell to Cell inspection, which relies on comparing gray level differences between the defect site and adjacent sites or a reference image. However, while pixel size and grey level differences are small enough that defect is not easy to be detected as device shrink beyond, hot spot and die to database (D2DB) inspection that can help to distinguish true defects from a large amount of false alarm defects. These inspections provide timely and high efficiency feedback for health of line monitoring and yield improvement.