Kla Tencor Corporation

Kla-tencor Technologies Corporation

David Alles

Jun Ye

James Norman Wiley

Shauh-Teh Juang

Stan Stokowski

Michael J Wright

Yu Long Cao

Yen-Wen Lu

Damon Floyd Kvamme

Lance Glasser

Robert W Walsh

Daniel L Belin

Mehdi Vaez-Iravani

Stanley E Stokowski

Fred E Stanke

Daniel C Wack

Yalin Xiong

Wu Jiang

Mark Joseph Wihl

Frank Chilese

Daimian Wang

Pradeep Subrahmanyan

Aditya Dayal

George Q Chen

Li Wang

Chun Lee

Ilya Toytman

Gregg Anthony Inderhees

Michael Wright

Optical inspection methods and apparatus for high-resolution photomasks using only a test image. A filter is applied to an image signal received from radiation that is transmitted by or reflected from a photomask having a test image. The filter may be implemented using programmed control to adjust and control filter conditions, illumination conditions, and magnification conditions.

Inspecting high-resolution photolithography masks

An extreme ultraviolet (EUM) mask inspection system, comprising a light source to project EUV light along an optical axis, an illumination system to receive the EUV light from the source, the illumination system comprising a spectral purity filter (SPF), the SPF transmits a first portion of the EUV light along the optical axis toward a mask and the SPF comprising a plurality of at least partially reflective elements, said elements reflects a second portion of the EUV light off the optical axis, a projection system adapted to receive the first portion of the EUV light after it has illuminated the mask, a first detector array adapted to receive the image, and a second detector array to receive the second portion of the EUV light. The SPF may comprise one or more multilayer interference-type filters. Alternatively, the SPF comprises a thin film filter disposed on a grazing incidence mirror array.

Spectral purity filter and light monitor for an EUV reticle inspection system

Methods and apparatus relating to the inspection of photomasks are described. In an embodiment, an inspection tool may be automatically focused on a reticle utilizing various topographic mapping techniques. Other embodiments are also described.

Auto focus system for reticle inspection

A method for synchronizing sample stage motion with a time delay integration (TDI) charge-couple device (CCD) in a semiconductor inspection tool, including: measuring a lateral position of a stage holding a sample being inspected; measuring a vertical position of the stage; determining a corrected lateral position of an imaged pixel of the sample based on the measured lateral and vertical positions; and synchronizing charge transfer of the TDI CCD with the corrected lateral position of the imaged pixel.

Apparatus and method for synchronizing sample stage motion with a time delay integration charge-couple device in a semiconductor inspection tool

Methods and apparatus relating to electromagnetic beam (e.g., laser beam) conditioning are described. In an embodiment, electromagnetic beam conditioning may be performed utilizing reflectors to temporally differentiate electromagnetic beam subsections and sub-beams resulting in reduced spatial coherence of the beam. Other embodiments are also described.

Beam conditioning to reduce spatial coherence

Methods for detecting and classifying defects on a reticle are provided. One method includes acquiring images of the reticle at first and second conditions during inspection of the reticle. The first condition is different than the second condition. The method also includes detecting the defects on the reticle using one or more of the images acquired at the first condition. In addition, the method includes classifying an importance of the defects detected on the reticle using one or more of the images acquired at the second condition. The detecting and classifying steps are performed substantially simultaneously during the inspection.

Methods for detecting and classifying defects on a reticle

Methods and systems for inspecting a reticle are provided. In an embodiment, a system may include an inspection subsystem configured to form a first aerial image of the reticle. The first aerial image may be used to detect defects on the reticle. The system may also include a review subsystem coupled to the inspection subsystem. For example, the inspection and review subsystems may have common optics, separate optics and a common stage, or separate stages and a common handler. The review subsystem may be configured to form a second aerial image of the reticle. The second aerial image may be used to analyze the defects. In another embodiment, the system may include an image computer configured to receive image data from the inspection and review subsystems representing the first and second aerial images. The image computer may also be configured to perform one or more functions on the image data.

Methods and systems for reticle inspection and defect review using aerial imaging

Methods and systems for inspecting a reticle are provided. In an embodiment, a method may include forming an aerial image of the reticle using a set of exposure conditions. The reticle may include optical proximity correction (OPC) features. The method may also include detecting defects on the reticle by comparing the aerial image to a reference image stored in a database. The reference image may be substantially optically equivalent to an image of the reticle that would be printed on a specimen by an exposure system under the set of exposure conditions. The reference image may not include images of the OPC features. Therefore, a substantial portion of the defects include defects that would be printed onto the specimen by the exposure system using the reticle under the set of exposure conditions. The method may also include indicating the defects that are detected in critical regions of the reticle.

Methods and systems for inspecting reticles using aerial imaging and die-to-database detection

The present invention discloses methods of conducting surface inspections using summed light. One method includes the steps of measuring summed light intensity values for the substrate, generating comparison values for the substrate, and then comparing the measured summed light intensity values with the comparison values to determine whether there are defects in the substrate. In another embodiment, a method includes the steps of generating a reference cluster using measured summed light intensity values for selected portions of the inspection surface. Other summed light intensity values are measured and then compared with the reference cluster. Using this comparison, a determination is made as to whether a defect is present. Another embodiment uses a constant baseline signal which is compared to actual light intensity values to determine whether a substrate defect is present. In yet another embodiment a substrate is inspected for the presence of defects by conducting a pixel-by-pixel summed light inspection of the substrate.

Surface inspection system and method using summed light analysis of an inspection surface

Methods and systems for inspecting a reticle are provided. A method may include forming an aerial image of the reticle with an inspection system at a wavelength different from a wavelength of an exposure system. The method may also include correcting the aerial image for differences between modulation transfer functions (MTF) of the inspection system and the exposure system. In this manner, the corrected aerial image may be substantially equivalent to an image of the reticle that would be printed onto a specimen by the exposure system at the wavelength of the exposure system. In addition, the method may include detecting defects on the reticle using the corrected aerial image. The detected defects may include approximately all of the defects that would be printed onto a specimen by the exposure system using the reticle.

Methods and systems for inspecting reticles using aerial imaging at off-stepper wavelengths

A reusable circuit design for use with electronic design automation EDA tools in designing integrated circuits is disclosed, as well as reticle inspection and fabrication methods that are based on such reusable circuit design. The reusable circuit design is stored on a computer readable medium and contains an electronic representation of a layout pattern for at least one layer of the circuit design on an integrated circuit. The layout pattern includes a flagged critical region which corresponds to a critical region on a reticle or integrated circuit that is susceptible to special inspection or fabrication procedures. In one aspect of the reusable circuit design, the special analysis is performed during one from a group consisting of reticle inspection, reticle production, integrated circuit fabrication, and fabricated integrated circuit inspection.

Mechanisms for making and inspecting reticles

Disclosed is a method of inspecting a reticle defining a circuit layer pattern that is used within a corresponding semiconductor process to generate corresponding patterns on a semiconductor wafer. A test image of the reticle is provided, and the test image has a plurality of test characteristic values. A baseline image containing an expected pattern of the test image is also provided. The baseline image has a plurality of baseline characteristic values that correspond to the test characteristic values. The test characteristic values are compared to the baseline characteristic values such that a plurality of difference values are calculated for each pair of test and baseline characteristic values. Statistical information is also collected.

Growing community of inventors

Los Altos, CA, United States of America

David Alles