24 March 2015 Overlay metrology solutions in a triple patterning scheme
Author Affiliations +
Abstract
Overlay metrology tool suppliers are offering today several options to their customers: Different hardware (Image Based Overlay or Diffraction Based Overlay), different target designs (with or without segmentation) or different target sizes (from 5 um to 30 um). All these variations are proposed to resolve issues like robustness of the target towards process variations, be more representative of the design or increase the density of measurements.

In the frame of the development of a triple patterning BEOL scheme of 10 nm node layer, we compare IBO targets (standard AIM, AIMid and multilayer AIMid). The metrology tools used for the study are KLA-Tencor’s nextgeneration Archer 500 system (scatterometry- and imaging-based measurement technologies on the same tool).

The overlay response and fingerprint of these targets will be compared using a very dense sampling (up to 51 pts per field). The benefit of indie measurements compared to the traditional scribes is discussed. The contribution of process effects to overlay values are compared to the contribution of the performance of the target. Different targets are combined in one measurement set to benefit from their different strengths (performance vs size).

The results are summarized and possible strategies for a triple patterning schemes are proposed.
© (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Philippe Leray, Ming Mao, Bart Baudemprez, Nuriel Amir, "Overlay metrology solutions in a triple patterning scheme", Proc. SPIE 9424, Metrology, Inspection, and Process Control for Microlithography XXIX, 94240E (24 March 2015); doi: 10.1117/12.2087304; https://doi.org/10.1117/12.2087304
PROCEEDINGS
8 PAGES


SHARE
Back to Top