Preface Testing Integrated Circuits for manufacturing defects includes four basic disciplines. First of all an understanding of the origin and behaviour of defects. Secondly, knowledge of IC design and IC design styles. Thirdly, knowledge of how to create a test program for an IC which is targeted on detecting these defects, and finally, understanding of the hardware, Automatic Test Equipment, to run the test on. All four items have to be treated, managed, and to a great extent integrated before the term 'IC quality' gets a certain meaning and a test a certain measurable value. The contents of this book reflects our activities on testability concepts for complex digital ICs as performed at Philips Research Laboratories in Eindhoven, The Netherlands. Based on the statements above, we have worked along a long­ term plan, which was based on four pillars. 1. The definition of a test methodology suitable for 'future' IC design styles, 2. capable of handling improved defect models, 3. supported by software tools, and 4. providing an easy link to Automatic Test Equipment. The reasoning we have followed was continuously focused on IC qUality. Quality expressed in terms of the ability of delivering a customer a device with no residual manufacturing defects. Bad devices should not escape a test. The basis of IC quality is a thorough understanding of defects and defect models.

1 Introduction.- 1.1 The Main Topic.- 1.2 Test Objectives.- 1.3 Definition of Testability.- 1.4 Problem Statement: Strategies and Requirements.- 1.5 Outline.- 2 Defect-Oriented Testing.- 2.1 Reason.- 2.2 Defects and Faults.- 2.3 Defect-Fault Relationship: Inductive Fault Analysis.- 2.4 Fault-Defect Relationship: Process Monitoring Testing.- 3 Macro Test: A Framework for Testable IC Design.- 3.1 Introduction to the Macro Test Philosophy.- 3.2 Testability Synthesis within the Macro Test Concept.- 3.3 Integration of Macro Test into a Design & Test flow.- 3.4 Summary of Essential Macro Test Items.- 4 Examples of Leaf-Macro Test Techniques.- 4.1 Defect Modeling and Test Algorithm Development for Static Random Access Memories (SRAMs).- 4.2 Built-in Self-Test for Static Random Access Memories.- 4.3 Leaf-Macro Testability Study Aspects.- 5 Scan Chain Routing with Minimal Test Application Time.- 5.1 Leaf-Macro Access.- 5.2 Introduction to Scan Chain Routing.- 5.3 Scan Test Application Protocol.- 5.4 Scan Chain Routing Problem Formulation.- 5.5 Scan Chain Routing Cost Model.- 5.6 Scan Chain Routing Problem Complexity.- 5.7 Routing of Scan Registers into a Single Scan Chain.- 6 Test Control Block Concepts.- 6.1 Introduction.- 6.2 Test Control Block Requirements.- 6.3 Test Controller Architectures.- 6.4 Relation between a Test Control Block and Test Plans.- 6.5 Test Control Block Design Requirements.- 6.6 Optimal Test Control Block implementation.- 6.7 Test Control Block Design Example.- 6.8 Distributed Test Control.- 7 Exploiting Parallelism in Leaf-Macro Access.- 7.1 Introduction.- 7.2 Levels of Parallelism.- 7.3 Formal Definitions of Resources, Resource Compatibility and Parallelism.- 7.4 Test Compatibility Graphs.- 7.5 Resource Allocation versus Test Assembly.- 7.6 AlgorithmicImplementation and Experimental Results.- 8 Timing Aspects of CMOS VLSI Circuits.- 8.1 Introduction.- 8.2 Timing Models of Latches and Flip-Flops.- 8.3 Timing of Data Transfers.- 8.4 Clock Drivers.- List of Symbols and Abbreviations.- References.