JP2000067243A - Automatic defect information collection control method and recording medium recording automatic defect information collection control program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to efficiently perform observation of a defect and a foreign matter by an electron microscope by permitting a detection method for automatically detect a singular point on the basis of inspection information to be arbitrarily changed. SOLUTION: A generation point of a defect or a foreign matter is specified by using an abnormal part detection device 1, a singular point is automatically detected by using an electron microscope 6 on the basis of inspection result information 2 such as a detection method of the abnormal part detection device 1 or defective foreign matter coordinates, and information on the detected singular point is observed and processed. An automatic detection method of the singular point is set by a singular point detection setting means 3. Detection of the singular point of defect information collection by a normal electron microscope discriminates the detection method by pattern information of an inspection point. These pieces of information are obvious before the inspection by the electron microscope By using this pattern information before the detection of the singular point, it is possible to omit movement of a reference point by a wafer where a pattern is not observed at the time of the singular point detection and the inspection of the singular point can be efficiently performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron microscope for observing pattern defects and foreign substances detected on fine patterns such as LSI wafers, TFTs and masks, or storing observation information. It is used for automating the observation of foreign substances.

[0002]

2. Description of the Related Art Along with the recent miniaturization of semiconductor devices, defects and foreign substances that need to be inspected are miniaturized in manufacturing inspection of semiconductor devices, and it is difficult to observe such defective portions in detail using an optical microscope. It has become. Therefore, as a conventional high-resolution defect / contamination observation technique, a defect inspection apparatus or a foreign substance inspection apparatus is used to specify the location where the defect or foreign substance has occurred, and information such as the coordinate origin and the defect foreign substance coordinates provided by the inspection apparatus is provided. Based on this, high-resolution observation of defects and foreign substances is performed using an electron microscope with a coordinate function or the like. Japanese Patent Application Laid-Open No. 9-139406 is a patent that takes these systemizations into consideration.

[0003]

In the above-mentioned electron microscope system, pattern matching and the like are performed on an electron microscope based on information on defects and foreign substances provided by the inspection apparatus.
A defect or an abnormal part is automatically detected as a singular point.

According to the present invention, there is provided, in addition to the prior art, means for arbitrarily changing a detection method for automatically detecting an abnormal part as a singular point from an abnormal part existing area based on information obtained by an inspection method of an inspection apparatus. It is an object of the present invention to efficiently observe defects and foreign substances with an electron microscope.

[0005]

According to the present invention, there is provided a step of reading inspection information of an abnormal part inspection apparatus for inspecting an abnormal part on an object to be inspected, and detecting an abnormal part existing area based on the information of the abnormal part inspection apparatus. A step of automatically detecting an abnormal part as a singular point, an observation processing step of obtaining information about the singular point, a step of setting the singular point automatic detection method based on information of the abnormal part inspection apparatus, The method includes a step of determining a pattern state of the inspected object based on information of the object, and automatically setting the singular point automatic detection method based on the determination result.

[0006]

Embodiments of the present invention will be described below.

In the present invention, as shown in FIG. 1, an abnormal part inspecting apparatus 1 is used to specify a position where a defect or a foreign matter has occurred, and the inspection method of the abnormal part inspecting apparatus 1 and inspection result information such as defect foreign substance coordinates are provided. Based on this, the singular point is automatically detected using the electron microscope 6, and information on the detected singular point is observed. The method for automatically detecting the singular point is set by the singular point detection setting means.

[0008] Defect information collection by a normal electron microscope is as follows.
First, based on the coordinate information provided by the abnormal part inspection apparatus 1, the sample is aligned with the electron microscope sample stage.
Subsequently, the visual field of the electron microscope is moved to the inspection point where the foreign substance is present, and a secondary electron image is taken into the electronic computer as a defect image. Thereafter, when no pattern is observed on the substrate to be inspected by an electron microscope such as an unprocessed semiconductor substrate, a defect position is specified from a luminance change of a secondary electron image captured on an electronic computer. Or, when a pattern is observed on a substrate to be inspected by an electron microscope, such as a semiconductor substrate in the middle of a manufacturing process, the field of view of the electron microscope is moved to a reference point, which is the same chip inside table of an adjacent chip, A secondary electron image is taken into a computer as a reference image, and then moved to an inspection point. After that, the secondary electron image of the inspection point is taken in as a defect image, and an image comparison is performed from the two images by a pattern matching method to specify a defect position.

After the detection of the singular point, an arbitrary matrix centered on the detection result is set as the observation center magnification, the observation magnification is set to the maximum observable magnification, and the image is stored, and observation processing such as length measurement is performed. As described above, several methods are conceivable for detecting a singular point in defect information collection by a normal electron microscope, and these methods determine a detection method based on pattern information of an inspection point. The pattern information of the inspection point is clear information before the inspection with the electron microscope, and by using this pattern information before detecting the singular point, the movement of the reference point on the wafer where the pattern is not observed when detecting the singular point Can be omitted, and the inspection of a singular point can be performed efficiently.

In the defect inspection apparatus, which is the abnormal part inspection apparatus 1, there are cases where only the same periodic pattern portion is inspected,
Two modes are considered when inspecting portions other than the same periodic pattern. In the mode in which only the same periodic pattern is inspected, the defect point provided by the abnormal part inspection apparatus is only the same periodic pattern.

Therefore, in the present invention, based on the feature of the inspection method of the abnormal part inspection apparatus, when only the same periodic pattern is the inspection target, the fact that the pattern of the reference image is always the same is used. Only one reference point is used without repeating the movement to the point and the movement to the inspection point. Thereby, there is no need to move to the reference point every time, and efficient inspection can be performed.

Further, since the defect does not move to the reference point for each defect, it is possible to prevent the pattern from being damaged by the electron beam, such as contamination of the reference point caused by irradiating the reference point with an electron beam.

Further, in a mode in which a portion other than the same periodic pattern is inspected, it is determined whether or not the pattern is a periodic pattern by using information such as the periodic information of the pattern. Without performing the inspection, the inspection to move to the reference point in the non-periodic pattern portion can be performed for each inspection point, and the movement to the reference point in the periodic pattern portion can be prevented. This flow is shown in FIG. First,
The inspection result 7 from the abnormal part inspection apparatus is read, and a mode for inspecting parts other than the same periodic pattern is set. Next, after moving to the inspection point and acquiring the inspection image, it is determined whether or not the inspection point has the same periodic pattern. If the inspection point is not the same periodic pattern, the inspection point is moved to the reference point and the reference image is acquired. If it is a periodic pattern, it moves to the reference point only once and acquires a reference image. Then, automatic detection 8 of a singular point is performed by a method such as image comparison by a pattern matching method, and observation processing of the last detected singular point is performed. The number of inspection points that the user wants to inspect from moving to the defect point to observing the singular point,
Repeat only for inspection points.

FIG. 3 shows an example of the singular point automatic detection method setting means. The user sets “no pattern type” 17, “periodic pattern type” 18, and “pattern present type” 19 based on pattern information given in advance or the inspection mode of the abnormal part inspection apparatus. Here, “Patternless type” is a method of detecting a singular point from a single inspection image without moving to a reference point. Only the reference point, and using the same reference image, a method of detecting a singular point from the reference image, the inspection image, and two images. A method of moving a point to detect a singular point from a reference image and two inspection images is shown. The "automatic determination type" 20 represents a method of automatically determining whether or not an inspection point is a periodic pattern, based on previously obtained periodic information of the periodic pattern portion.

[0015]

According to the present invention, the processing time in the high-resolution automatic observation of the defect and the foreign matter can be shortened, the observation can be performed efficiently, and the effect of reducing the damage of the inspection object by the electron microscope can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an automatic defect information collection control method of the present invention.

FIG. 2 is a flowchart showing an automatic defect information collection control method of the present invention.

FIG. 3 is a diagram showing a screen configuration example according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Abnormal part inspection apparatus, 2 ... Information on test results, such as abnormal part inspection method, 3 ... Singularity automatic detection method setting means, 4 ...
Singular point automatic detection means, 5 ... Singular point information, observation processing means, 6 ... Electron microscope, 7 ... Reading of inspection results from abnormal part inspection device, 8 ... Singular point automatic detection method setting, 9 ... Repeat N times (N : All the inspection points), 10 ... moved to the inspection point, 11
... Acquisition of inspection image, 12 ... Determine whether it is a periodic pattern,
13: Move to reference point, 14: Acquisition of reference image, 15: Automatic detection of singular point, 16: Information of singular point, observation processing, 17: Type selection button without pattern, 18: Periodic pattern type selection button, 19: With pattern Type selection button,
20: Automatic discrimination type selection button, 21: Singular point detection execution button, 22: Singular point automatic detection method setting screen.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Atsushi Shimoda 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside the Hitachi, Ltd. Production Technology Laboratory Co., Ltd. F-term in Hitachi, Ltd. Production Technology Laboratory (reference) 2G001 AA03 BA07 CA03 FA02 GA01 GA06 HA01 HA13 JA13 JA16 KA03 LA11 MA05 4M106 AA01 AA09 BA02 CA38 DB01 DB05 DB21 DB30 DJ17 DJ18 DJ20 DJ38 5B057 CH01 DA03 DA08 DB02 DC05 DC36

Claims (6)

[Claims] 1. A method of controlling automatic collection of a defect image by a programmed computer, comprising: reading inspection information of an abnormal part inspection apparatus for inspecting an abnormal part on an inspection object; Automatically detecting an abnormal part as a singular point from an abnormal part existing area based on the information of the abnormal part, an observation processing step of obtaining information about the singular point, and automatically detecting the singular point based on information of the abnormal part inspection apparatus. An automatic defect information collection control method, comprising a step of setting a method. 2. The method according to claim 1, wherein the step of setting the singularity automatic detection method based on the information of the abnormal part inspection apparatus includes the step of changing a pattern state of the inspection object based on the information of the inspection object. An automatic defect information collection control method, comprising a step of determining and automatically setting the singular point automatic detection method from the determination result. 3. An electron microscope having an automatic defect image collection control function by a programmed computer, comprising: reading means for reading inspection information of an abnormal part inspection apparatus for inspecting an abnormal part on an inspected object; Detecting means for automatically detecting an abnormal part as a singular point from an abnormal part existing area based on information of the abnormal part inspection apparatus, observation processing means for obtaining information on the singular point, and information based on the information of the abnormal part inspecting apparatus. An electron microscope with an automatic defect information collection control function, which comprises setting means for setting the singular point automatic detection method. 4. A setting means for setting a singularity automatic detection method based on information of an abnormal part inspection apparatus according to claim 3,
An electron microscope comprising means for judging a pattern state of the object to be inspected based on the information of the object to be inspected, and automatically setting the singular point automatic detection method based on the discrimination result. Automatic defect information collection control method. 5. A recording medium recording a control program for controlling collection of automatic defect images by a computer, said control program being transmitted from an abnormal part inspection apparatus for inspecting an abnormal part on an inspection object to a computer. The inspection information of the abnormal part is automatically detected as a singular point from the abnormal part existing area based on the information of the abnormal part inspection apparatus, and an observation process of obtaining information about the singular point is performed.
A recording medium recording an automatic defect information collection control program, wherein the detection means is set based on information of the abnormal part inspection apparatus. 6. A control program for causing a computer to set the automatic detection method based on information on an abnormal part inspection apparatus according to claim 5,
A recording medium which records an automatic defect information collection control program characterized by a control program for judging a pattern state of the object to be inspected and automatically setting a singular point automatic detection method on a computer based on the judgment result.