Abstract: 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 zeroth diffraction 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.

Abstract: 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.

Abstract: Disclosed are apparatuses, methods, and lithographic systems for holographic mask inspection. A holographic mask inspection system (300, 600, 700) includes an illumination source (330), a spatial filter (350), and an image sensor (380). The illumination source being configured to illuminate a radiation beam (331) onto a target portion of a mask (310). The spatial filter (350) being arranged in a Fourier transform pupil plane of an optical system (390, 610, 710), where the spatial filter receives at least a portion of a reflected radiation beam (311) from the target portion of the mask. The optical system being arranged to combine (360, 660, 740) the portion of the reflected radiation beam (311) with a reference radiation beam (361, 331) to generate a combined radiation beam. Further, the image sensor (380) being configured to capture holographic image of the combined radiation beam. The image may contain one or more mask defects.

Abstract: 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.

Abstract: 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.

Abstract: 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 zeroth diffraction 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.

Abstract: 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.