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Product Briefing Outline: KLA-Tencor has launched into the advanced wafer defect review and classification market with the introduction of the ‘eDR-5200' system. The new tool has been designed to seamlessly integrate KLA-Tencor's inspection tools with the eDR-5200 to enable fabs at the 45nm node and beyond to produce a greater number of higher quality defect Paretos per hour, allowing engineers to take rapid, accurate corrective action to protect yields, according to the company. The eDR-5200 has been shipped to customers in Asia, Europe and the U.S., where it is being installed for both memory and logic applications.

Problem: As design rules shrink to 45nm and beyond, defect and yield engineers are becoming increasingly concerned about the quality of the defect Pareto coming from their review tools. A large number of ‘Not Found' or ‘SEM Non-Visual (SNV)' defects skew the defect Pareto, which is used to make key decisions during both yield ramp and process monitoring. Improved resolution of the tools is required to accurately capture and review defects; however, a broad range of operating conditions is necessary to achieve best resolution on the wide variety of materials and geometries employed in advanced devices. For example, 193nm resists are often the most challenging, requiring soft landing energy to avoid damage to the imaged layers.

Solution: The eDR-5200 introduces an immersion column design to address the need to image and classify <50nm defects. Bathing the imaged area in a strong electromagnetic field enables nearly 2X better resolution. The tool is claimed to have the widest range of beam conditions to best meet demanding imaging needs. The inspector's recipe can be set up and optimized for maximum sensitivity and lower SNV rate, eliminating multiple transports of the wafer between the systems, and freeing the inspection tool for additional inspections. The eDR-5200 employs an innovative EDX design that uses new algorithms to enable analysis and classification of defects less than 100nm in diameter, based on their composition. Because an electron beam interacts with only the surface of a layer, previous-layer defects are traditionally classified as SNV. A new approach to the problem of SNV has been applied using proprietary optical information from KLA-Tencor inspection tools that allows characterization of previous-layer defects by displaying their optical image resulting in more defects of interest on the wafer being identified, and in a shorter time.

Applications: Wafer defect review and classification for the 45nm and below.

Platform: The eDR-5200 is equipped with a high precision stage and advanced defect de-skewing algorithms. Together, these can reduce SNV rates by increasing the ability of the SEM review tool to capture <50nm defects. Set-up free, power-assisted defect classification (ePAC) and a learn-as-you-go classification engine are also employed enabling the user to easily transition from manual classification to fully-automated defect classification (eADC).

Availability: July 2007 onwards.