Departmental Papers (ESE)


As we approach atomic-scale logic, we must accommodate an increased rate of manufacturing defects, transient upsets, and in-field persistent failures. High defect rates demand reconfiguration to avoid defective components, and transient upsets demand online error detection to catch failures. Combining these techniques we can detect in-field persistent failures when they occur and reconfigure around them. However, since failures may be logically masked for long periods of time, persistent failures may accumulate silently; this integration of errors over time means the effective failure rate for persistent errors can exceed transient upset rates. As a result, logic scrubbing is necessary to prevent the silent accumulation of an undetectable number of persistent errors. We provide simple analysis to illustrate quantitatively how this phenomena can be a concern.

Document Type

Conference Paper

Date of this Version

September 2008


Copyright 2008 IEEE. Reprinted from Proceedings of the 2008 IEEE International Workshop on Design and Test of Nano Devices, September 2008, pages 67-70.

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fault tolerance, logic scrubbing, reconfiguration, reliability, testing



Date Posted: 12 December 2008

This document has been peer reviewed.