Asml Holding N.v.

Robert Tharaldsen

Yuli Vladimirsky

Yevgeniy Konstantinovich Shmarev

Eric Brian Catey

Richard Jacobs

Nora-Jean Harned

Muhammad Arif

An apparatus and a method to detect a defect or particle on a surface that involves combining an object radiation beam redirected by the surface with a reference radiation beam having a plurality of intensities lower than the object radiation beam, to produce a plurality of patterns detected by a detector in order to detect the defect or particle on the surface from the patterns.

Lithographic apparatus and device manufacturing method

A patterning device, including alignment targets having alignment features formed from a plurality of diffractive elements, each diffractive element including an absorber stack and a multi-layered reflector stack is provided. The diffractive elements are configured to enhance a pre-determined diffraction order used for pre-alignment and to diffract light in a pre-determined direction of a pre-alignment system when illuminated with light of a wavelength used for the pre-alignment. The diffractive elements may occupy at least half of an area of each alignment feature. The diffractive elements may be configured to enhance first or higher order diffractions, while substantially reducing zerodiffraction orders and specular reflection when illuminated with a wavelength used for reticle prealignment. The dimensions of each diffractive element may be a function of a diffraction grating period of each alignment feature.

Diffraction elements for alignment targets

Disclosed are systems and methods for time differential reticle inspection. Contamination is detected by, for example, determining a difference between a first signature of at least a portion of a reticle and a second signature, produced subsequent to the first signature, of the portion of the reticle.

Time differential reticle inspection

A method and systems for reticle inspection. The method includes coherently illuminating surfaces of an inspection reticle and a reference reticle, applying a Fourier transform to scattered light from the illuminated surfaces, shifting the phase of the transformed light from the reference reticle such that a phase difference between the transformed light from the inspection reticle and the transformed light from the reference reticle is 180 degrees, combining the transformed light as an image subtraction, applying an inverse Fourier transform to the combined light, and detecting the combined light at a detector. An optical path length difference between two optical paths from the illumination source to the detector is less than a coherence length of the illumination source. The image detected by the detector represents a difference in amplitude and phase distributions of the reticles allowing foreign particles, defects, or the like, to be easily distinguished.

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Sherman, CT, United States of America

Robert Tharaldsen