Total measurement uncertainty (TMU) is a commonly used key performance indicator (KPI) for tool-induced error in metrology systems. Several definitions of TMU are being used today for overlay metrology (OVL), with the leading definition being the root-sum-square (RSS) of three other KPIs: the wafer mean Tool Induces Shift (TIS𝜇), the wafer variability of TIS (TIS3σ), and the OVL measurement reproducibility (OVL precision). A multitude of TIS management methods has been developed and implemented over the years for calibrating out the raw TIS from OVL. With these TIS management methods in place, the use of the raw TISμ and TIS3σ in TMU no longer serves as a good characterization of the total tool-induced error. In this paper, we describe a procedure for evaluating the actual, post-TIS management, OVL Metrology TMU through the introduction of two new wafer level indicators: the effective wafer means TIS (eTISμ), and the effective wafer TIS variability (eTIS3σ).
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.