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Product Briefing Outline: KLA-Tencor has revealed its latest advancement in darkfield patterned wafer inspection technology in the Puma 9150 system. The tool features new optical modes that enable capture of a broader range of yield-critical defects for 45nm production while providing the highest available darkfield production throughputs, reducing operating cost and allowing higher sampling rates for tighter process control, according to the company. KLA-Tencor has shipped Puma 9150 systems to memory and logic customers in all chipmaking regions, including multiple systems to several fabs. The system is being used for 65nm production, 45nm ramp, and sub-45nm R&D.

Problem: At the 45nm node, IC manufacturers are faced with increasing yield challenges due to shrinking dimensions, new materials and innovative device structures.  A key aspect in minimizing killer defects while maintaining sufficient production throughputs requires improved defect capture across the broadest defect range.

Solution: In addition to traditional single and double darkfield optical modes, the Puma 9150 incorporates new darkfield and edgefield optical modes. These multiple optical modes provide improved defect type capture across an extended application space. High resolution darkfield imaging is produced by combining line scanning with a multi-pixel sensor. This technology is claimed to enable high sensitivity inspections without compromising throughput. Defect detection on film layers is possible with the system's unique optical features, which are claimed to maximize surface selectivity and noise suppression. Multiple optical modes allow for increased sensitivity to bridging, shorts and other pattern defects in the etch process, and provide improved capture of residue and other critical defects from CMP. For photocell monitoring and after-develop inspection, the Puma 9150 also provides a high sampling option to broadband brightfield inspection. Improved nuisance suppression is obtained with multiple optical modes, selectable incident and collection polarizations, Fourier filters and new algorithms. This combines with ‘inLine Defect Organizer' (iDO, automated defect binning) to reduce time to provide meaningful results that focus on the most critical yield issues.

Applications: The capture of low profile, large area defects, such as underpolish and slurry residues from copper CMP as well as low-profile line-short defects in copper CMP layers.  It also improves darkfield defect capture in etch applications, such as microbridges and partially- or fully-blocked vias.

Platform: The Puma 9150 shares a common platform and user interface with KLA-Tencor's broadband brightfield and e-beam inspectors. This facilitates a mix-and-match inspection strategy. Tool-to-tool matching provides the same results on any Puma system without modifying the inspection recipe. 2x higher data rates are claimed to result in higher throughputs than the Puma 9000. Recipe setup time has been reduced by over 70 percent, which can be optimized offline on a KLA-Tencor SEM review station, protecting inspector capacity and further reducing recipe optimization cycle time.

Availability: June 2007 onwards.