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Product Briefing Outline: Applied Materials has launched the ‘Applied Aera2’ for critical dimension uniformity (CDU) lithography applications. Using the system’s ‘IntenCD’ technology in the fab, semiconductor manufacturers can improve CDU by more than 20%, increasing device yield and lowering the per-wafer cost of patterning, according to the company. The Aera2 can be used to extend photomask lifetime and bring productivity gains to the entire lithography cell.

Problem: At the 45nm node and below, especially for double patterning, at least half of the variation in CD comes from the mask. Designed to emulate a scanner, Aera2 with IntenCD correlates linearly with the wafer CD effect created by different sources of mask variation. Generating this information in the fab allows for optimized mask cleaning intervals and therefore extends mask availability and lifetime.

Solution: Key to this new lithography application is the Aera2 platform’s IntenCD technology that creates high precision, high definition CDU maps from the aerial image of an entire reticle. By replacing wafer-based measurements with IntenCD maps, the time to decision shrinks from two days to as little as an hour, and accuracy improves by eliminating cumulative errors that can arise from multiple wafer processing steps. The improved uniformity data allows advanced scanners to compensate for CD variations, delivering major improvements in linewidth accuracy on product wafers and ultimately, increased yield. Regularly inspecting masks within the fab using the IntenCD technology can stretch photomask lifetime significantly. Mask properties change dynamically and non-uniformly with cumulative exposure, inducing CD errors from haze defect growth and pellicle degradation. By replacing traditional fixed mask reconditioning intervals with predictive scheduling, fab managers can use the Aera2 system to minimize mask reconditioning cycles, increasing mask lifetime and availability.

Applications: Critical dimension uniformity (CDU) lithography/mask applications.

Platform: To optimize cycle time, the industry-leading Applied Tetra™ Reticle Clean system can also be added to the lithography cell, eliminating the need to send masks outside the fab for reconditioning. Equipped with IntenCD for high-density, high-precision scanning of the entire reticle, Aera2 can generate maps of CD trends that could signal manufacturing process problems.  Global trends can be resolved to approximately 1nm. Mapping occurs concurrent with inspection and can be performed for a range of applications and simultaneously for multiple feature sizes.

Availability: December 2008 onwards.