Use of layout analysis to enable efficient and effective random defect inspection using a vector-mode e-beam inspection machine

Abstract

A vector e-beam machine for random defect inspection is disclosed. Contrary to traditional wisdom, it is shown that through a careful choice of target locations, vector machines can provide high-throughput and high coverage even when scanning for random defects. Additionally, by not wastefully scanning locations that provide no additional fault observability, charge accumulation on the wafer—a major concern in e-beam scanning—is reduced. In a preferred embodiment, two approaches are combined: 1) Scan/target only at locations where a random failure can be observed. 2) From the defined list of observable locations, scan/target only the points which have the highest efficiency. Use of these and/or other disclosed techniques enables the scanner to target and evaluate a majority of the total observable defects in a single pass.

Dependencies are inferred from the claim text.