7 March 2008 Modeling of focus blur in the context of optical proximity correction
Author Affiliations +
Abstract
The concept of focus blur encompasses the effect of laser bandwidth longitudinal chromatic aberration and scanner stage vertical vibration. The finite bandwidth of excimer laser source causes a corresponding finite distribution of focal planes in a range of 100nm or larger for the optical lithography system. Similarly, scanner vertical stage vibration puts the wafer in a finite distribution of focal planes. Both chromatic aberration and vertical stage vibration could introduce significant CD errors, hence can no longer be ignored in current lithography processes development and OPC development that require CD control within a few nanometers. We developed several methodologies to model the laser chromatic aberration and vertical stage vibration in OPC (Optical Proximity Correction) modeling tool. Extensive simulations were done to calculate chromatic aberration and vertical stage vibration focus blur's impact on lithography patterning for a variety of test structures. Chromatic aberration and vertical stage vibration focus blur effect was further included as an regression term in experimental OPC model calibration to capture its impact on litho patterning, and significant benefit to OPC model calibration was observed.
© (2008) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Qiaolin Zhang, Qiaolin Zhang, Hua Song, Hua Song, Kevin Lucas, Kevin Lucas, James Shiely, James Shiely, } "Modeling of focus blur in the context of optical proximity correction", Proc. SPIE 6924, Optical Microlithography XXI, 69243K (7 March 2008); doi: 10.1117/12.773091; https://doi.org/10.1117/12.773091
PROCEEDINGS
9 PAGES


SHARE
Back to Top