Hitachi-high-technologies Corporation

Hitachi, Ltd.

Hitachi Power Solutions Co., Ltd.

Hitachi-ge Nuclear Energy, Ltd.

Kaoru Sakai

Shunji Maeda

Takafumi Okabe

Minoru Yoshida

Atsushi Shimoda

Hidetoshi Nishiyama

Toshio Asano

Masahiro Watanabe

Yuta Urano

Tetsuo Taguchi

Isao Tanaka

Akira Hamamatsu

Hisae Shibuya

Hiroshi Goto

Mineo Nomoto

Takahiro Urano

Masayuki Kuwabara

Naoya Takeuchi

Osamu Kikuchi

Daiske Katsuta

Kenji Sahara

Toshifumi Honda

Tadashi Furukawa

Jun Mochizuki

Tatsuo Horiuchi

Atsuo Ohsawa

Hirofumi Nakatoyodome

In an ultrasonic inspection performed on an inspection object including a fine and multi-layer structure such as a semiconductor wafer and a MEMS wafer, a defect is detected by: separating a defect present inside from a normal pattern; obtaining an image of the inspection object by imaging the inspection object having a pattern formed thereon to enable a highly sensitive detection; generating a reference image that does not include a defect from the obtained image of the inspection object; generating a multi-value mask for masking a non-defective pixel from the obtained image of the inspection object; calculating a defect accuracy by matching the brightness of the image of the inspection object and the reference image; and comparing the calculated defect accuracy with the generated multi-value mask.

Defect inspection method and apparatus

Disclosed is a defect inspection device that has an illumination optical system; a detection optical system; and a processing unit which includes a defect feature quantity calculation unit that calculates the feature quantities of each defect candidate, a defect candidate grouping unit that groups the aforementioned defect candidates on the basis of the feature quantities, a defect classification evaluation value calculation unit that calculates defect classification evaluation values for the aforementioned defect candidates, a defect classification evaluation value updating unit that, on the basis of instructions, updates the evaluation values, a defect classification threshold determination unit that, on the basis of evaluation valued updated by the aforementioned defect classification evaluation value updating unit, determines a classification boundary that is a threshold for classifying defect types of the aforementioned defect candidates, and a defect detection unit that detects defects using the thresholds.

Defect inspection device and defect inspection method

The pattern inspection apparatus of the present invention performs comparison between images of regions corresponding to patterns formed to be same patterns, thereby determining mismatch portions across the images to be defects. The apparatus includes multiple sensors that synchronously acquire images of shiftable multiple detection systems different from one another, and an image comparator section corresponding thereto. In addition, the apparatus includes a means for detecting a statistical offset value from the feature amount to be a defect, thereby properly detecting the defect even when a brightness difference is occurring in association with film a thickness difference in a wafer.

Method and apparatus for inspecting patterns formed on a substrate

The invention provides a defect inspection method and a defect inspection device which enable a defect to be inspected regardless of optical conditions. The invention comprises the steps of setting a target local region and a plurality of corresponding local regions in the image signals, the target local region including a target pixel and an area surrounding the target pixel, the corresponding local regions including pixels corresponding to the target pixel and areas surrounding the corresponding pixels; searching similarities between the image signal of the target local region and the image signals of the plurality of corresponding local regions; determining a plurality of image signals that represent corresponding local regions and are similar to the image signal of the target local region; and comparing the image signal of the target local region with the image signals that represent the corresponding local regions.

Defect inspection method and device thereof

A pattern inspection apparatus is provided to compare images of regions, corresponding to each other, of patterns that are formed so as to be identical and judge that non-coincident portions in the images are defects. The pattern inspection apparatus is equipped with an image comparing section which plots individual pixels of an inspection subject image in a feature space and detects excessively deviated points in the feature space as defects. Defects can be detected correctly even when the same patterns in images have a brightness difference due to a difference in the thickness of a film formed on a wafer.

A defect inspection apparatus includes an illumination optical system which irradiates an inspection subject under a predetermined optical condition, a detection optical system which obtains image data by detecting a scattered light from the inspection subject irradiated by the illumination optical system, and an image processing unit provided with a defect candidate detection unit which detects defect candidates with respect to plural image data obtained by the detection optical system under different conditions, and a post-inspection processing unit which executes a defect determination by integrating the defect candidates with respect to the plural image data.

Apparatus and method for inspecting defect

A method of detecting a defect, including the steps of: illuminating step for illuminating a sample with a light; detecting step for detecting light from the specimen which is illuminated by the light and forming an image by processing the detected light; processing step for extracting a defect candidate by processing the image of the sample formed in the detecting step and determining an inspection condition by using images including the image of the sample acquired in the detecting step, a partial image including the extracted defect candidate and a reference image which corresponds to the partial image including the defect candidate.

Method and apparatus for inspecting pattern defects

A fault inspection method and apparatus in which the scattergram is separated or objects of comparison are combined in such a manner as to reduce the difference between an inspection object image and a reference image. As a result, the difference between images caused by the thickness difference in the wafer can be tolerated and the false information generation prevented without adversely affecting the sensitivity.

Fault inspection method

In a pattern inspection apparatus, influences of pattern brightness variations that is caused in association with, for example, a film thickness difference or a pattern width variation can be reduced, high sensitive pattern inspection can be implemented, and a variety of defects can be detected. Thereby, the pattern inspection apparatus adaptable to a broad range of processing steps is realized. In order to realize this, the pattern inspection apparatus of the present invention performs comparison between images of regions corresponding to patterns formed to be same patterns, thereby determining mismatch portions across the images to be defects. The apparatus includes multiple sensors capable of synchronously acquiring images of shiftable multiple detection systems different from one another, and an image comparator section corresponding thereto. In addition, the apparatus includes means of detecting a statistical offset value from the feature amount to be a defect, thereby enabling the defect to be properly detected even when a brightness difference is occurring in association with film a thickness difference in a wafer.

The invention relates to a defect inspection apparatus in which images of mutually corresponding areas in identically formed patterns on a sample are compared to detect mismatched portions of the images as defects. The defect inspection apparatus includes an image comparator that creates a feature space with the use of feature quantities calculated from pixels of images acquired under different optical conditions and detects outlier values in the feature space as defects. Thus, the defect inspection apparatus can detect various defects with high sensitivity even if there are luminance differences between images of identical patterns which are attributable to the difference in wafer pattern thickness.

Defect inspection method and apparatus therefor

In an inspection subject substrate, there is a problem that a defect signal is overlooked due to scattered light from a pattern and sensitivity decreases in an irregular circuit pattern part. The inventors propose a defect inspection method, characterized by comprising: an illumination step of guiding light emitted from a light source to a predetermined area on an inspection subject substrate under a plurality of predetermined optical conditions; a detection step of obtaining an electric signal by guiding scattered light components propagating in a predetermined range of azimuthal angle and in a predetermined range of elevation angle to a detector for each of a plurality of scattered light distributions occurred correspondingly to the plurality of optical conditions in the predetermined area; and a defect determination step of determining a defect based on the plurality of electric signals obtained in the detection step.

Defect inspection system and method of the same

An apparatus for inspecting pattern defects, the apparatus including: an image acquisition unit which acquires an image of a specimen and stores the acquired image in an image memory; a defect candidate extraction unit which performs a defect candidate extraction process by using the acquired image, which is read from the image memory; and a defect detection unit which performs a defect detection process based on a partial image containing a defect candidate that is extracted by the defect candidate extraction unit, wherein the defect detection process performed by the defect detection unit is performed asynchronously with an image acquisition process that is performed by the image acquisition unit.

According to the present invention, for a pattern inspection apparatus that compares images in corresponding areas of two patterns that are identical and that determines an unmatched portion between the images is a defect, a plurality of detection systems and a plurality of corresponding image comparison methods are provided. With this configuration, the affect of uneven brightnesses for a pattern that occurs due to differences in film thicknesses can be reduced, a highly sensitive pattern inspection can be performed, a variety of defects can be revealed, and the pattern inspection apparatus can be applied for processing performed within a wide range. Furthermore, the pattern inspection apparatus also includes a unit for converting the tone of image signals of comparison images for a plurality of different processing units, and when a difference in brightness occurs in the same pattern of the images, a defect can be correctly detected.

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Yokohama, Japan

Kaoru Sakai