Presented at SPIE's Advanced Lithography 2007

February 2007

ABSTRACT
Advances in lithography create a unique challenge for process window control with defect inspection tools. As the technology moves towards smaller line widths and more complicated structures, the sensitivity requirements for some process defects become higher, such as defocus and dose defects at 50 nm or lower technology nodes. Currently, automated macro inspection tools are used to detect a wide range of macro defects in the litho area such as coating defects, particles, and scratches, as well as the process defects. Most tools, however, cannot satisfy the new sensitivity requirements for the process defects while maintaining their current inspection capability for other defects. Rudolph Technologies approaches this challenge by integrating a unique polarization-imaging configuration, which enhances detection of defocus and dose defects without sacrificing the existing capability to detect other types of macro defects. The improved inspection system has demonstrated high sensitivity for defocus and dose defects on production wafers at multiple process nodes at high throughput.

Read the full paper here.