Kla Tencor Corporation

Kla Corporation

Phillip Atkins

Liequan Lee

Shankar Krishnan

Alexander Kuznetsov

Houssam Chouaib

Dawei Hu

Paul Aoyagi

Natalia Malkova

Mikhail M Sushchik

Qi Dai

David C S Wu

Manh Nguyen

Emily Chiu

A metrology system may receive a model for measuring one or more selected attributes of a target including features distributed in a selected pattern based on regression of spectroscopic scatterometry data from a scatterometry tool for a range of wavelengths. The metrology system may further generate a weighting function for the model to de-emphasize portions of the spectroscopic scatterometry data associated with wavelengths at which light captured by the scatterometry tool when measuring the target is predicted to include undesired diffraction orders. The metrology system may further direct the spectroscopic scatterometry tool to generate scatterometry data of one or more measurement targets including fabricated features distributed in the selected pattern. The metrology system may further measure the selected attributes for the one or more measurement targets based on regression of the scatterometry data of the one or more measurement targets to the model weighted by the weighting function.

Scatterometry modeling in the presence of undesired diffraction orders

A parameterized geometric model of a structure can be determined based on spectra from a wafer metrology tool. The structure can have geometry-induced anisotropic effects. Dispersion parameters of the structure can be determined from the parameterized geometric model. This can enable metrology techniques to measure nanostructures that have geometries and relative positions with surrounding structures that induce non-negligible anisotropic effects. These techniques can be used to characterize process steps involving metal and semiconductor targets in semiconductor manufacturing of, for example, FinFETs or and gate-all-around field-effect transistors.

Measurement methodology of advanced nanostructures

Methods and systems for performing spectroscopic measurements of asymmetric features of semiconductor structures are presented herein. In one aspect, measurements are performed at two or more azimuth angles to ensure sensitivity to an arbitrarily oriented asymmetric feature. Spectra associated with one or more off-diagonal Mueller matrix elements sensitive to asymmetry are integrated over wavelength to determine one or more spectral response metrics. In some embodiments, the integration is performed over one or more wavelength sub-regions selected to increase signal to noise ratio. Values of parameters characterizing an asymmetric feature are determined based on the spectral response metrics and critical dimension parameters measured by traditional spectral matching based techniques.

Detection and measurement of dimensions of asymmetric structures

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San Jose, CA, United States of America

Phillip Atkins