| Popis: |
Methods to improve accuracy of pattern matching are investigated with our software tool (k1 TUNE). Since pattern matching handles experimental data, resist simulation accuracy, SEM measurement accuracy, and identification of illumination situations used in the software and set in actual scanners are crucial. The methods to reduce their error are proposed. In addition to reducing them, a subtracting method is used to compensate them for better pattern matching. The effectiveness is certificated experimentally with accuracy of 0.010 sigma of illumination and 1~2nm of CD. Furthermore an illumination that keeps CDs constant under defocus is optimized, and the characteristics are confirmed experimentally. By using the software tool under the proposed ways, real pattern matching at fabrication lines has been possible with good accuracy, few retry, and consideration of defocus characteristics. |
