Rudolph Technologies, Inc.

Isoa, Inc.

Other

Texas Instruments Corporation

Youling Lin

Kathleen Hennessey

A Kathleen Hennessey

Ramakrishna Pattikonda

Yonghang Fu

Yongqiang Liu

David W Herod

Yan Wang

Masami Yamashita

C Rinn Cleavelin

Rajasekar Reddy

Howard V Hastings, Ii

Wan S Wong

Max Guest

Charles Harris

Ichiro Shimomura

Veera V S Khaja

Pinar Kinikoglu

George C Epp

A system for precisely measuring layer-to-layer mis-registration is provided. The system includes a new type of mark and a comparison system, which compare the right and left signals from the mark to eliminate non-alignment noise, to enlarge the alignment information hundreds times then the actual shiftiness between two layers and to measure the mis-registration.

Differential method for layer-to-layer registration

A system and method for inspecting structures formed on the surface of an object using ultraviolet (UV) light. The object is placed in position and illuminated with at least one wavelength of UV light, directed at its surface from a UV source. At the moment of illumination, an image is captured by a UV-light sensitive camera positioned at an angle calculated to intercept light diffracted at particular an angle of diffraction associated with the pattern of structures formed on the surface of the object. To avoid having to repeatedly reposition the camera, one (or more in succession) illumination wavelength is selected to direct an intensity peak associated with a particular order of diffraction at the camera location. Ideally, a visible-light sensitive camera is also used to capture images of the surface when illumination with UV light results in the emanation of light in the visible portion of the spectrum.

Optical inspection method utilizing ultraviolet light

An optical inspection system and method for inspecting a component on a printed circuit board (PCB) which determines three-dimensional information in a single scan. A first visual light source illuminates the PCB surface and component with a green light while a second visual light source illuminates the PCB and component with a blue light. At least one laser light source simultaneously illuminates the surface of the PCB with a narrow coherent red-light laser beam. The laser light source is mounted off vertical on a movable mount which enables the laser beam to be directed over an area of interest on the surface of the PCB. The system also includes a color scan camera mounted vertically above the PCB. The camera has red, green, and blue channels. The green and blue channels capture an image of the illuminated surface of the PCB which is used by a computer to determine two-dimensional information about the component. The red channel captures a path of the laser beam as it strikes the surface of the PCB and the component. The computer uses the path to determine height information for the component.

System and method for three-dimensional surface inspection

A system and method for performing optical inspection of structures on the surface of a semiconductor wafer. The wafer surface is illuminated with a polychromatic light source. A multiple-charged couple-device (CCD) camera is positioned to capture light diffracted by the structures on the wafer surface at the first order of diffraction. The captured light is then separated into a plurality of component wavelengths which are directed onto the CCDs. A digital filter creates a plurality of digitized diffractive images of the wafer surface at different component wavelengths. The diffractive images may be integrated and analyzed to detect defects in the structures, or may be, analyzed individually. An image at a particular wavelength may be selected and analyzed by using the known grating pitch of the structures to calculate the wavelength.

System and method for performing optical inspection utilizing diffracted light

A system and method for detecting defects in surface structures, such as those formed on semiconductor wafers. A light source, preferably a strobe light, provides illumination that is separated by a filter into a plurality of selected bandwidths. The light then is transported through a fiber optic cable to a diffuser, and from there directed toward the surface. A camera captures a plurality of images, each image formed by a separate portion of the electromagnetic spectrum. The images may be formed by either reflected or diffracted light, or both. The images may be stored or compared to an image of a calibration wafer.

System and method for multi-wavelength, narrow-bandwidth detection of surface defects

A method of collating and using captured semiconductor-wafer image data in an automated defect analysis. The method includes the steps of receiving image data and, if necessary, converting it to a digital format. Once the data is in pixel-by-pixel form, each pixel is assigned a slope value derived from the direction of the structure edge, if any, on which it lies. The pixel-slope data is then evaluated to determine whether a photo-resist anomaly is present. The method may also include evaluated an average pixel slope value for each inspected wafer. Dependant claims further define the invention to claim an inspection system for employing the method.

System and method for detecting defects on a structure-bearing surface using optical inspection

A system and method of optically inspecting a structure on a surface of a production object which is supported on a moving inspection platform. The method reliably traces structure edges and stores structure and structure island characteristics. The system uses a camera and a light or energy source to sharply delineate the structure edges. A sequence of images of the object and the structure are captured, and the structure is detected in each image. The structure is then symbolically decomposed into primitives, and a histogram is produced for each image identifying the slope and length of each edge of the structure. The histograms are compared in each image, and are aligned to eliminate differences due to wobble of the inspection platform or differences in magnification. A production structure grammar is then produced from the aligned images. The production structure grammar is compared to a reference structure grammar generated from a defect-free object. Differences in the two grammars, if any, are used to identify missing, misaligned, or misoriented structures on the production object, and to detect foreign objects and other defects.

System and method of optically inspecting structures on an object

A method and system for generating and managing a knowledgebase for use in identifying anomalies on a manufactured object, such as a semiconductor wafer, includes measures for adding, deleting, and organizing data from the knowledgebase.

System and method for classifying an anomaly

A system and method of optically inspecting structures on the surface of an object, such as a semiconductor wafer. A platform is used to support the object under examination, and provided thereat are lights or other energy sources for illumination disposed at a selected angular orientation. Optimum illumination is achieved by orienting two opposing lateral energy sources to direct energy along the surface of the object at a very low angle, and using them in conjunction with a coaxial light source that emits energy, which is directed downward toward the surface. Energy reflected back from the surface is captured as an image by a suitable device such as a CCD camera. The lighting may be controlled by an attached computer, which can also be used to process and store the captured image and analyze it to detect and catagorize defects in the object being inspected.

System and method of optically inspecting surface structures on an object

An apparatus, system, and method of optically inspecting printed circuit boards (PCBs) for defects, that reliably determines the dimensions of components including those having the same color as the background, and which can detect components which are missing, misoriented, misaligned, or not properly seated. The apparatus uses a camera and a coherent primary light source mounted at an angle away from the vertical so as to produce sharply defined PCB component shadows on the top surface of the PCB. An image of the PCB is captured, the shadow edges are symbolically decomposed into primitives from which gradients are produced, and then compared to a previously captured gradient of a defect-free PCB. Differences in the two image gradients, if any, are used to identify missing, misaligned, misoriented, and improperly seated components, and to detect foreign objects and other PCB defects.

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Richardson, TX, United States of America

Youling Lin