Getting accurate fault isolation during failure analysis is mandatory for success of Physical Failure Analysis (PFA) in critical applications. Unfortunately, achieving such accuracy is becoming more and more difficult with today’s diagnosis tools and actual process node such as BCD9 and FinFET 7 nm, compromising the success of subsequent PFA done on defective SoCs. Electrical simulation is used to reproduce emission microscopy, in our previous work and, in this paper, we demonstrate the possibility of using fault simulation tools with the results of electrical test and fault isolation techniques to provide diagnosis with accurate candidates for physical analysis. The experimental results of the presented flow, from several cases of application, show the validity of this approach.

This paper describes a novel flow using analog simulations for the failure analysis of digital, analog, and mixed signal devices. Although cell level diagnosis tools are available in the industry, it presents a solution through analog intra-cell simulation particularly advantageous when multiple defects give the same fault result at cell level. Details of case studies such as the one analog intracell simulation on digital device and the analog laser voltage probing are covered. The aim of the simulation solution proposed is to support the failure analyst to interpret emission images on analog devices. The presented analog simulation flow consists of computing the current (or current density) in MOS and bipolar transistors and simulating the internal waveforms in digital or analog cells. It enables failure analysts to interpret light emission and laser voltage probing results obtained on a physical device in a fast and efficient way.

The present work is relative to a new software suite that features design comprehension and analogic/logic tracing capability with ease of setup in FA laboratory environment. It also expands and correlates FA measure data to design functionality. With this visibility enhanced environment, we show that FA process can be performed more efficiently. Up to now, very few systems have been built with aim to cover advanced diagnosis setup and real-time navigation with synchronized simulation. We address a general FA software tool which purpose is to automate the design database setup and provide to FA engineer capability to launch reading of all design database including capability of generating new patterns compatible with analytical tools. Based on the flow, we propose a series of tools that will allow the FA engineer to work efficiently.

Logic diagnosis is the process of isolating the source of observed errors in a defective circuit, so that a physical failure analysis can be performed to determine the root cause of such errors. In this paper, we propose a new “Effect-Cause” based intra-cell diagnosis approach to improve the defect localization accuracy. The proposed approach is based on the Critical Path Tracing (CPT) here applied at transistor level. It leads to a precise localization of the root cause of observed errors. Experimental results show the efficiency of our approach.