Intelligent Defect Analysis (IDA) ™ is a suite of advanced software that enables semiconductor manufacturers to prevent yield loss through the early identification of defect sources. IDA leverages the expertise and knowledge of the defect engineer by providing him with a range of tools and functionality to automatically analyze non-random defect signatures.
IDA recipes, which may be easily integrated into the fab’s existing yield management system, automatically monitor production inspection results files. They recognize the “fingerprints” resulting from equipment failures and process excursions, including scratches, streaks, rings, and clusters. When a defect signature is identified, the fab engineer is notified immediately.

A defect spatial signature is a systematic distribution of defects on the surface of the wafer. The streak (a) and the circle (b) are identified using the object rules library; CMP scratches (c) are detected using a special scratch algorithm; a center ring (d) is identified using zonal analysis.

IDA employs several different signature recognition techniques to automatically identify the spatial signatures that may affect process yield. These techniques may be used in combination to provide high accuracy and purity. These techniques include:

• Object rules library (cluster technique)
• Wafer and reticle pattern library ( k-NN matching)
• Pre-defined signature algorithms (linear algebra)
• Layer-to-layer and reticle repeater analysis
• Zonal analysis (user defined regions)

IDA software suite comprises three main components:

Defect Signature Analyzer (DSA™) provides yield engineers with a wide range of analysis and visualization tools with which to develop and optimize the signature analysis methodology and to train the defect signature library.

Automation Workbench (AWB™) allows engineers to automate the signature analysis methodology to run the recipe in either batch mode or continuous monitor mode.

Intelligent Reporting System (IRS™) generates a data base of analysis results. Long term trends may be analyzed using a pivot table. Signature analysis results may be exported to an Excel file.

Each IDA recipe generates a data base of defect signature analysis results and automatically notifies fab personnel when a process excursion is detected. IDA enables the applications engineer to optimize the signature recognition recipe for each inspection step and provides a critical component of Advanced Process Control.

Key Benefits of IDA

• Reduced WIP exposure - immediate feedback allows fab to limit losses from process excursions.
• Early warning - identifies potential problems that fall below SPC defect count limits.
• Standardization - provides consistent methodology for analyzing inspection results.
• Improved analysis - identifies systematic defects that are hard to find with manual analysis .
• Increased efficiency - defect engineers can work on yield problems instead of reviewing KLARF files.
• Reduced Equipment Downtime - notify engineer of root cause immediately upon signature recognition.