Kla Corporation

Alon Alexander Volfman

Yuval Lubashevsky

Itay Gdor

Vladimir Levinski

Daria Negri

Yevgeniy Men

Elad Farchi

Yaniv Weiss

A method for overlay metrology may include generating broadband illumination beams and directing the broadband illumination beams to an overlay target on a sample, where the overlay target may include cells having periodic features formed as overlapping grating structures. The method may include generating diffracted light using the periodic features of the overlay target, where the periodic features may act as a diffraction grating to generate diffracted light by separating the broadband illumination beam into a plurality of wavelengths. The method may include generating pupil images of cells of the overlay target, where a distribution of light in the pupil plane may include first-order diffraction lobes, where spectra of the first-order diffraction lobes may be spatially dispersed in the pupil plane. The method may include generating an overlay measurement based on portions of the pupil images corresponding to selected wavelengths of the spectra of the first-order diffraction lobes.

Single grab pupil landscape via broadband illumination

Metrology is performed on a semiconductor wafer using a system with an apodizer. A spot is formed on the semiconductor wafer with a diameter from 2 nm to 5 nm. The associated beam of light has a wavelength from 400 nm to 800 nm. Small target measurement can be performed at a range of optical wavelengths.

Annular apodizer for small target overlay measurement

Growing community of inventors

Tel Aviv, Israel

Alon Alexander Volfman