Product Briefing Outline: Applied Materials has introduced the ‘Applied Inflexion’ edge polishing system for high-precision defect removal that polishes and cleans the critical wafer edge region. The Applied Inflexion is claimed to be the only system that polishes the entire wafer edge, removing film stack residues and shallow surface defects in a single pass while minimizing the exclusion area in order to maximize the number of good die. In addition, the system precisely controls the edge profile, enabling process engineers to tailor the film-to-wafer interface to meet a wide range of integration requirements. 

Problem: As feature sizes shrink and device manufacturers look for ways to maximize the number of die per wafer, edge engineering has emerged as a way to improve overall die yield. The wafer edge is increasingly recognized as a potential source of yield-limiting defects, driving the need to optimize the quality of the edge. In addition, the need to improve productivity by increasing the number of die per wafer pushes the boundaries of the edge exclusion zone, shrinking them down to 1mm or less.

Solution: The Applied Inflexion system’s high productivity platform can be configured with up to three processing modules to deliver twice the throughput of competing edge polishing systems. The system integrates Applied’s ‘Desica’ single wafer wet cleaner to assure defect performance on all surfaces. Using abrasive tape with proprietary head technology, the Inflexion system provides a non-selective process that is designed to efficiently remove all materials, including metal/dielectric stack residues not easily removed by other cleaning methods, from the entire edge region that comprises the notch, bevel, apex, and front and back exclusion zones. Inflexion also effectively removes shallow surface defects, such as pits from the substrate, which can act as particle traps. At 45nm and beyond, both of these issues are expected to have a greater impact on device yield when immersion lithography processes are adopted into high-volume manufacturing. Eliminating these types of defects can potentially increase overall yield by up to 10 percent, according to the company.

Applications: Defect removal and high-precision edge engineering for logic and memory devices, supporting both FEOL and BEOL applications.

Platform: When the Applied Inflexion system is used in conjunction with the Applied ‘SEMVision’ G4 defect review tool, these systems provide a comprehensive wafer edge defect removal, review and analysis solution, enabling customers to successfully characterize and control edge defect issues, especially in immersion lithography.

Availability: May 2008 onwards.