| Autor: |
Mike Bohan, M. Duane, Paul C. Allen, Peter Pirogovsky, Eric R. Christenson, Malik K. Sadiq, Sam C. Howells, Boaz Kenan, Michael White, Robin Teitzel, H. Dai, Henry Chris Hamaker |
| Rok vydání: |
2005 |
| Předmět: |
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| Zdroj: |
SPIE Proceedings. |
| ISSN: |
0277-786X |
| Popis: |
The capability and performance of the production-proven DUV ALTA 4300 system has been extended by the development of two new optical subsystems: a 0.9 NA, 42X reduction lens and a high-bandwidth acousto-optic deflector based beam position and intensity correction servo. The PSM overlay performance has been improved by modifications to the software algorithms. The enhanced performance, delivered by these subsystem improvements, has been introduced as a new product-the ALTA 4700. Characterization data show improved resolution performance in line end shortening, through pitch CD bias and feature corner acuity. The AOD subsystem reduces stripe beam placement errors and random and systematic beam intensity errors. This has enabled local CD uniformity to be reduced to 4.3 nm (3σ) and global CD uniformity to be reduced to 6 nm (3σ). Second layer overlay performance is now 20 nm (max error). This paper also demonstrates superior X-Architecture performance delivered by the ALTA 4700. Characterization data show global CD uniformity in 0°, 45°, 90°, and 135° orientations better than 6.5nm (3σ); mean CD control in all 4 orientations less than 3.6nm; and smooth angled lines through a wide range of angles. A split lot wafer evaluation demonstrates the equivalence of wafers produced DUV ALTA system reticles vs. those produced with reticles from a 50kV electron beam system. The evaluation shows the interchangeability of these two systems for 90nm Metal 1 applications-with no changes to the wafer OPC (originally optimized for the 50kV system). Characterization data focus on final wafer electrical performance-the performance characteristic that determines ultimate integrated circuit device yield. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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