The effect of defect clustering on test transparency and defect levels

Abstract

Proposes a wafer based testing approach which for the first time employs defect clustering information on the wafer to optimize test cost and defect levels in the shipped product. Preliminary analysis of this approach had assumed that the probability that a test detects a faulty circuit is independent of the number of faulty dies in the neighborhood of the circuit under test. Here, the authors relax this assumption by making test transparency a function of the number of faults. In this paper they study the effect of clustering on test transparency and defect levels based on maps of particle distributions on test wafers.<>