Modern electronics testing has a legacy of more than 40 years. The introduction of new technologies, especially nanometer technologies with 90nm or smaller geometry, has allowed the semiconductor industry to keep pace with the increased performance-capacity demands from consumers. As a result, semiconductor test costs have been growing steadily and typically amount to 40% of today's overall product cost. 

This book is a comprehensive guide to new VLSI Testing and Design-for-Testability techniques that will allow students, researchers, DFT practitioners, and VLSI designers to master quickly System-on-Chip Test architectures, for test debug and diagnosis of digital, memory, and analog/mixed-signal designs.

KEY FEATURES
* Emphasizes VLSI Test principles and Design for Testability architectures, with numerous illustrations/examples.
* Most up-to-date coverage available, including Fault Tolerance, Low-Power Testing, Defect and Error Tolerance, Network-on-Chip (NOC) Testing, Software-Based Self-Testing, FPGA Testing, MEMS Testing, and System-In-Package (SIP) Testing, which are not yet available in any testing book.
* Covers the entire spectrum of VLSI testing and DFT architectures, from digital and analog, to memory circuits, and fault diagnosis and self-repair from digital to memory circuits.
* Discusses future nanotechnology test trends and challenges facing the nanometer design era; promising nanotechnology test techniques, including Quantum-Dots, Cellular Automata, Carbon-Nanotubes, and Hybrid Semiconductor/Nanowire/Molecular Computing.
* Practical problems at the end of each chapter for students.

System-on-Chip Test Architectures: Nanometer Design for Testability

At-speed scan is a key technique in modern IC testing. One of its drawbacks, with respect to functional tests, is its excessive power consumption leading to voltage drop and frequency degradation. This paper discusses the frequency and power correlation between At-speed scan and functional tests. The influence of voltage drop on frequency is demonstrated by silicon measurements and supporting simulation results. The localized nature of the voltage drop as well as impedance component analysis are presented. Additionally, the need for power aware scan patterns is also discussed. Suggestions for achieving a higher correlation between At-speed scan and functional patterns, with respect to power consumption, are offered.

Frequency and Power Correlation between At-Speed Scan and Functional Tests

Power-aware test is increasingly becoming a major manufacturing test consideration due to the problems of increased power dissipation in various test modes as well as test implications that arise due to the usage of various low-power design technologies in devices today. Several challenges emerge for test engineers and test tool developers, including (and not restricted to) understanding of various concerns associated with power-aware test, development of power-aware design-for-test (DFT), automatic test pattern generation (ATPG) techniques, and test power analysis flows, evaluation of their efficacy and ensuring easy/rapid deployment. This paper highlights concerns and challenges in power-aware test, surveys various practices drawn from both academia and industry, and points out critical gaps that need to be addressed in the future.

Power-aware test: Challenges and solutions

This paper presents a novel method to generate test vectors that mimic functional operation from switching activity point of view. The method uses states obtained by applying a number of functional clock cycles starting from the scan-in state of a test vector to fill the unspecified scan cell values in test cubes. Experimental results presented for industrial circuits demonstrate the effectiveness of the proposed method.

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At-speed scan test with low switching activity

As technology scales to 32 nm and functional frequency and density continue to rise, PSN effects, which can reduce a circuit's noise immunity and could lead to failures, pose new challenges to chip manufacturers and foundries. This article provides an overview of low-power and delay testing, and surveys ongoing research for analyzing and dealing with PSN effects during delay test and timing analysis.

Power Supply Noise: A Survey on Effects and Research

When the response to a test vector is captured by state elements in scan based tests, the switching activity of the circuit may be large resulting in abnormal power dissipation and supply current demand High supply current may cause excessive supply voltage droops leading to larger gate delays which may cause good chips to fail tests This paper presents a scalable approach called Preferred Fill to reduce average and peak power dissipation during capture cycles of launch off capture delay fault tests Experimental results presented for benchmark and industrial circuits demonstrate the effectiveness of the proposed method

Preferred Fill: A Scalable Method to Reduce Capture Power for Scan Based Designs

Supply current and power dissipation during scan based test may be much higher than during normal circuit operation due to larger switching activity caused by the tests. Higher peak current demands may cause supply voltage droops causing good chips to fail at-speed tests. Higher average switching activity causes higher power dissipation and chip temperature that may cause hot spots and damage circuits under test. Several works have proposed methods to derive tests with lower peak and average switching activity during test response capture or during scan shifts. Some of these methods require additional hardware and modifications to the scan chains. This paper investigates a method to derive tests with reduced switching activity both during scan shifts and during test response captures. The method does not require additional hardware or modifications to the scan chains. The proposed method accepts a given test set and returns a test set of the same or smaller size with reduced switching activity. Experimental results on benchmark and industrial circuits are given

Low Shift and Capture Power Scan Tests

As digital circuits grow in gate count so does the data volume required for manufacturing test. To address this problem several test compression techniques have been developed. This paper presents a novel and scalable technique for inserting observation points to aid compression by reducing pattern count and data volume. Experimental results presented for industrial circuits demonstrate the effectiveness of the method.

ATPG Heuristics Dependant Observation Point Insertion for Enhanced Compaction and Data Volume Reduction

Supply current and power dissipation during scan-based test can be far higher than during normal circuit operation because of increased switching activity caused by the tests In this paper, we propose a method that fills unspecified entries in test cubes to reduce the switching activity caused by scan tests simultaneously during the scan-shift and capture cycles Our method doesn't require additional hardware or modifications to the scan chains

Scan-Based Tests with Low Switching Activity

This paper presents a scalable method to generate close to minimal size test pattern sets for stuck-at faults in scan based circuits. The method creates sets of potentially compatible faults based on necessary assignments. It guides the justification and propagation decisions to create patterns that will accommodate most targeted faults. The technique presented achieves close to minimal test pattern sets for ISCAS circuits. For industrial circuits it achieves much smaller test pattern sets than other methods in designs sensitive to decision order used in ATPG.

Santiago Remersaro

Papers

Preferred Fill: A Scalable Method to Reduce Capture Power for Scan Based Designs

Low Shift and Capture Power Scan Tests

ATPG Heuristics Dependant Observation Point Insertion for Enhanced Compaction and Data Volume Reduction

Scan-Based Tests with Low Switching Activity

A scalable method for the generation of small test sets