Patent application number | Description | Published |
20090296096 | Interferometric Defect Detection - Methods and systems for using common-path interferometry are described. In some embodiments, a common-path interferometry system for the detection of defects in a sample is described. An illumination source generates and directs coherent light toward the sample. An optical imaging system collects light reflected from the sample including a scattered component of that is predominantly scattered by the sample, and a specular component that is predominantly undiffracted by the sample. A variable phase controlling system is used to adjust the relative phase of the scattered component and the specular component so as to improve the ability to detect defects in the sample. | 12-03-2009 |
20110075151 | INTERFEROMETRIC DEFECT DETECTION AND CLASSIFICATION - Systems and methods for using common-path interferometric imaging for defect detection and classification are described. An illumination source generates and directs coherent light toward the sample. An optical imaging system collects light reflected or transmitted from the sample including a scattered component and a specular component that is predominantly undiffracted by the sample. A variable phase controlling system is used to adjust the relative phase of the scattered component and the specular component so as to change the way they interfere at the image plane. The resultant signal is compared to a reference signal for the same location on the sample and a difference above threshold is considered to be a defect. The process is repeated multiple times each with a different relative phase shift and each defect location and the difference signals are stored in memory. This data is then used to calculate an amplitude and phase for each defect, which can be used for defect detection and classification. This method is expected to detect much smaller defects than current inspection systems and to find defects that are transparent to these systems. | 03-31-2011 |
20110075928 | High-resolution, common-path interferometric imaging systems and methods - High-resolution, common-path interferometric imaging systems and methods are described, wherein a light source generates and directs light toward a sample. An optical imaging system collects the resultant substantially scattered component and substantially unscattered component. A variable phase shifting system is used to adjust the relative phase of the scattered and unscattered light components. The interfered components are sensed by an image sensing system. The process is repeated multiple times with different phase shifts to form corresponding multiple electronic signals representative of raw sample images. The raw sample images are then processed by a signal processor to form a processed image, where each image pixel has an amplitude and a phase. This picture can be displayed directly using some combination of brightness and color to represent amplitude and phase. Multiple processed images, each corresponding to a different illumination azimuth angle, can be combined to substantially extend the resolution. The technique permits the optical aberrations in the imaging system to be measured and removed from each picture. The addition of phase and amplitude to microscopic images is expected to extend both the depth and breadth of the many applications of optical microscopy. | 03-31-2011 |
20110242528 | OPTICAL IMAGING SYSTEM WITH CATOPTRIC OBJECTIVE; BROADBAND OBJECTIVE WITH MIRROR; AND REFRACTIVE LENSES AND BROADBAND OPTICAL IMAGING SYSTEM HAVING TWO OR MORE IMAGING PATHS - An optical system may include an objective having at least four mirrors including an outermost mirror with aspect ratio <20:1 and focusing optics including a refractive optical element. The objective provides imaging at numerical aperture >0.7, central obscuration <35% in pupil. An objective may have two or more mirrors, one with a refractive module that seals off an outermost mirror's central opening. A broad band imaging system may include one objective and two or more imaging paths that provide imaging at numerical aperture >0.7 and field of view >0.8 mm. An optical imaging system may comprise an objective and two or more imaging paths. The imaging paths may provide two or more simultaneous broadband images of a sample in two or more modes. The modes may have different illumination and/or collection pupil apertures or different pixel sizes at the sample. | 10-06-2011 |
20110280038 | Systems for and methods of illumination at a high optical solid angle - Illumination systems and methods that utilize the higher or outer portions of the optical solid-angle space to increase the illumination intensity are disclosed. The illumination systems and methods include introducing illumination light through at least one side surface of a transparent slide that operably supports a sample on its top surface. The light fills at least a portion of the optical solid-angle space between 1 and n, and extends out to n. Light from the filled portion of the optical solid-angle space illuminates the sample through the top surface of the transparent slide. The disclosed illumination systems and methods are suitable for use in applications, such as dark-field imaging, fluorescence imaging, Raman spectroscopy, DNA analysis and like applications requiring high-intensity illumination. | 11-17-2011 |
20130155399 | OPTICAL IMAGING SYSTEM WITH CATOPTRIC OBJECTIVE; BROADBAND OBJECTIVE WITH MIRROR; AND REFRACTIVE LENSES AND BROADBAND OPTICAL IMAGING SYSTEM HAVING TWO OR MORE IMAGING PATHS - An optical system may include an objective having at least four mirrors including an outermost mirror with aspect ratio <20:1 and focusing optics including a refractive optical element. The objective provides imaging at numerical aperture >0.7, central obscuration <35% in pupil. An objective may have two or more mirrors, one with a refractive module that seals off an outermost mirror's central opening. A broad band imaging system may include one objective and two or more imaging paths that provide imaging at numerical aperture >0.7 and field of view >0.8 mm. An optical imaging system may comprise an objective and two or more imaging paths. The imaging paths may provide two or more simultaneous broadband images of a sample in two or more modes. The modes may have different illumination and/or collection pupil apertures or different pixel sizes at the sample. | 06-20-2013 |
20130278942 | DARK FIELD DIFFRACTION BASED OVERLAY - A dark field diffraction based overlay metrology device illuminates an overlay target that has at least three pads for an axis, the three pads having different programmed offsets. The overlay target may be illuminated using two obliquely incident beams of light from opposite azimuth angles or using normally incident light. Two dark field images of the overlay target are collected using ±1 | 10-24-2013 |
20130286179 | Apparatus and methods for microscopy having resolution beyond the Abbe limit - Microscope apparatus and methods for imaging an object with a resolution beyond the Abbe limit are disclosed. The apparatus employs an object selectively patterned with a fluorescing material that is induced to fluoresce with one wavelength and inhibited from fluorescing with a second wavelength. Two orthogonal interference-fringe patterns are generated from four diffracted light beams of an inhibiting wavelength and superimposed on the object along with light that induces fluorescence. The interference-pattern image allows only sub-resolution-sized emission areas of the object to fluoresce. Multiple images of the fluorescing object are obtained, each corresponding to a slightly different position of the fringe patterns on the substrate. Each image is processed to yield a sparsely sampled super-resolution image. Multiple sparse images are interwoven to form a complete super-resolution image of the object. | 10-31-2013 |
20150043803 | Phase-controlled model-based overlay measurement systems and methods - Overlay measurement systems and methods are disclosed that control the relative phase between the scattered and specular components of light to amplify weak optical signals before detection. The systems and methods utilize model-based regressional image processing to determine overlay errors accurately even in the presence of inter-pattern interference. | 02-12-2015 |