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Product Briefing Outline: KLA-Tencor has officially introduced the new ‘Aleris’ family of films metrology systems, beginning with the Aleris 8500 which the company claims is the industry’s first system to combine production-worthy composition and multi-layer film thickness metrology into a single platform. Additional Aleris family systems will be introduced in the coming months in configurations to meet the performance and CoO requirements for all film applications at the 45nm node and below. Aleris 8500 systems have been shipped to several key customers where they are being used for 65nm gate control production and 45nm/32nm development. 

Problem: Until now, chipmakers have normally purchased separate analytical and traditional optical thickness metrology tools to provide thickness and composition measurements. This mix-and-match method has meant tolerating the inefficiencies of poor tool-tool matching, difficult capacity backup and incompatible recipes. Having all of the advanced critical films metrology applications available on a single Aleris platform helps chipmakers have the ability to improve cost of ownership and time to results. The Aleris 8500 offers 3x higher throughput compared to existing analytical techniques and its non-vacuum optical technology overcomes traditional analytical tool reliability constraints, according to the company.

Solution: The Aleris 8500 system features next-generation Broadband Spectroscopic Ellipsometry (BBSE) optics that are designed to provide a significant improvement in precision, matching and stability. This technology enables chipmakers to qualify and monitor advanced films, including new materials, structures and engineered substrates. The system uses a 150nm BBSE, which is intended to offer enhanced sensitivity to composition measurement, making Aleris 8500 the industry’s first single-tool solution for production monitoring of critical gate applications on product wafers, the company claims. Aleris’ StressMapper module provides higher spatial resolution at higher throughput, for production monitoring of 2D stress in high-stress films.

Applications: The Aleris 8500’s 150nm BBSE capability enhances sensitivity to composition measurement by providing 2x better repeatability and 4x better matching over the previous generation tools. This is a single tool solution for the product wafer composition and thickness measurements required to control critical nitrided gate and high-k dielectric applications. It also enables the measurement of the highly correlated top and bottom oxide layers in the ONO stacks. The extent of the correlation is driven by the thickness of the nitride layer separating the two oxides, which is becoming thinner and posing more of a correlation challenge. Because the nitride film has increased absorption characteristics at shorter wavelengths, use of shorter wavelengths increases the contrast between the top and bottom oxides. StressMapper’s laser-based tilt measurement provides higher sensitivity and spatial resolution, enabling true 2D local stress mapping. Significantly enhanced repeatability and matching, as well as high throughput, allow production monitoring of both global and 2D stress measurements on product wafers that have complicated film stacks, discontinuous films or pattern induced stress. This module enables measurement of FEOL low deflection and high stress films such as Si Nitride capping and implant anneal.

Platform: The Aleris 8500 system builds on the company’s SpectraFx 200 technology, featuring next generation Broadband Spectroscopic Ellipsometry (BBSE) optics. Ultraviolet Reflectometer’s (UVR) new design provides the best in class signal-to-noise ratio (>10x better than previous generation) to improve overall measurement performance.

Availability: November 2007 onwards.