JP2003023053A - Method for manufacturing semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a semiconductor device capable of displaying a defect on a substrate in a relatively short time on an output unit, without making mistake of defect positions. SOLUTION: The method for manufacturing the semiconductor device comprises steps of calculating a two-dimensional particle image 7 obtained by simultaneously scanning beams 2 to a relatively wide region on the substrate, thereby automatically detecting change points 10a, 11a of voltage contracts on the X-axis direction and the Y-axis direction for indicating the defect position, and obtaining position coordinates of the points 10a, 11a from deflecting voltages of the beams 2 without moving the stage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device manufacturing technique, and more particularly to a technique effectively applied to a process of detecting a defect on a substrate by an image type defect inspection.

[0002]

2. Description of the Related Art As semiconductor devices become highly integrated, their manufacturing processes are increasingly required to be complicated and precise. On the other hand, by introducing and effectively operating an inspection process at each point of the manufacturing line, the system of yield management and line management in the manufacturing process of the semiconductor device is strengthened.

Against this background, semiconductor device inspection methods are diversified. The image-type defect inspection, which is one of them, scans the substrate with, for example, a charged particle beam or a scanning laser beam to obtain two-dimensional image information of the pattern on the substrate, and outputs it by an output device such as a monitor. It is a means for detecting defects by displaying, and plays an important role in improving the yield of semiconductor devices.

Note that, for example, "Monthly Semiconductor World" August 1999 issue, P80-P84, published by Press Journal, Inc., describes user needs for a wafer defect inspection apparatus.

[0005]

In order to perform defect analysis of defects, collection of image data of defects, or mark processing for defect analysis, for example, the positioning of defects on the substrate detected in the image type defect inspection is performed. When it becomes necessary, conventionally, the defect is located by manual work. However, as a result of examination by the present inventor, it has been clarified that artificial positioning of a defect requires a great amount of time to specify the defective portion, and causes a problem that the defective portion is mistaken.

It is an object of the present invention to provide a technique capable of displaying a defect on a substrate in an output device in a relatively short time and without erroneous detection of a defective portion.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0008]

Among the inventions disclosed in the present application, a brief description will be given to the outline of typical ones.
It is as follows.

According to the present invention, in the image type defect inspection process,
The beam is collectively scanned over a relatively wide area on the substrate to acquire a secondary particle image, and the change point of the voltage contrast is automatically detected by performing arithmetic processing on the secondary particle image,
Further, a defect image is displayed on the output device by using the position coordinates of the change point obtained from the beam deflection voltage.

According to the present invention, in the image type defect inspection process,
A device that displays the defect image on the output device by counting the pulse number of the secondary particle signal obtained by scanning the beam over a relatively wide area on the substrate at one time and using the position coordinate of any bit obtained by this Is.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. In all the drawings for explaining the embodiments, members having the same function are designated by the same reference numerals, and the repeated description thereof will be omitted.

(First Embodiment) An example of a method of processing image information according to the first embodiment will be described with reference to FIGS. FIG. 1 is a schematic view showing a charged particle beam device, FIG.
3 is a schematic diagram showing a beam scanning direction, FIG. 3 is a schematic diagram of image data stored in a storage medium, and FIG. 4 is a schematic diagram of an image device.

As shown in FIG. 1, a charged particle beam system 1
Is a device that scans the substrate 2 with the beam 2 in a certain width in a certain direction to detect the secondary particle signal 3, and obtains image information by the brightness of the voltage distribution (hereinafter referred to as voltage contrast). By using the ion beam for the beam 2, it is possible to obtain a larger change in voltage contrast than the electron beam. Here, the substrate is a semiconductor wafer or a semiconductor chip, and the semiconductor wafer 4 is exemplified in the first embodiment.

First, as shown in FIG. 2, a beam 2 generated by the charged particle beam apparatus 1 is collectively scanned at a relatively low magnification on a relatively wide partial region 5 on a semiconductor wafer 4. The area 5 is composed of a plurality of patterns mounted on the substrate, and for example, a TEG of a contact hole chain.
(Test element group) can be illustrated.

Next, as shown in FIG. 3, a secondary particle image (image data) 7 is obtained by combining the secondary particle signal 3 obtained by the charged particle beam device 1 and the scanning synchronization signal 6, and The secondary particle image 7 and the position coordinates (position data) obtained from the deflection voltage of the beam are provided in the collective image storage format, and these are stored in the storage medium 8 as image data. The position coordinates include, for example, the position (x,
y) and the deflection distance (defx, defy) of the beam are input. Further, the secondary particle image 7 or a part thereof is output and displayed on an output device, for example, the monitor 9 shown in FIG.

Next, the method of detecting the defect on the substrate in the secondary particle image and obtaining the position coordinates of the defect on the secondary particle image according to the first embodiment will be described with reference to FIGS. 5 to 7. To do. FIG. 5 is a schematic diagram showing the result of integrating the secondary particle image and all voltage contrasts in the X direction and the Y direction of the secondary particle image, and FIG. 7 is a diagram showing the scanning distance of the beam on the substrate and the deflection voltage. FIG. 6 is a graph showing the relationship of FIG. 6, and FIG. 6 is a schematic diagram for explaining a method of determining a change point of voltage contrast.

If there is a defect on the substrate, for example, as shown in FIG. 5, a change point 10a appears in the integration result 10 of the voltage contrast in the X direction obtained by the calculation of the secondary particle image 7, and similarly the Y direction. The change point 11a appears in the integration result of the voltage contrast 11 of. These change points 10a in the X direction
And the change point 11a in the Y direction indicates a defect location detected in the secondary particle image 7.

As a method of calculating the secondary particle image 7, in addition to the method of integrating all the voltage contrasts in the X and Y directions of the secondary particle image 7 shown in FIG.
For example, a method of integrating the voltage contrasts of a part of the secondary particle image 7 in the X direction and the Y direction, or a method of calculating the voltage contrasts of one scanning line of the secondary particle image 7 in the X direction and the Y direction, respectively. Can be used.

Various methods can be used to determine the change point of the voltage contrast. For example, as shown in FIG. 6, when the calculation result of the voltage contrast is the waveform 12, the amplitude 13, the peak intensity 14 or the differential peak intensity 15 of the calculation result is used, and when the calculation result of the voltage contrast is other than the waveform, For example, the change point 16 of the calculation result
Alternatively, the differential peak intensity 17 is used.

After detecting the change point of the voltage contrast,
The position coordinates 19 of the change point 10a in the X direction and the change point 11a in the Y direction from the beam deflection voltage 18 are calculated using the relationship between the beam scanning distance and the deflection voltage shown in FIG. 7 without moving the stage. That is, the position coordinates of the defect on the secondary particle image 7 are obtained. Furthermore, by performing three-point calibration of the deflection voltage and the deflection distance on the substrate, it becomes possible to improve the beam deflection accuracy. Therefore, the position coordinate of the defect can be obtained only by the error caused by the deflection accuracy of the beam without being affected by the movement accuracy of the stage.

As described above, according to the first embodiment, from the secondary particle image 7 obtained by collectively scanning the beam 2 on the relatively wide area 5 on the substrate, the X direction and the Change point 10 of each voltage contrast in the Y direction
a and 11a are automatically detected, and the position coordinates 19 of the change points 10a and 11a are obtained from the deflection voltage 18 of the beam 2. As a result, it is possible to accurately display the image of the defect on the substrate on the output device in a short time as compared with the manual work.

(Second Embodiment) A method of obtaining the position coordinates of a defect on a secondary particle image according to the second embodiment will be described with reference to the schematic diagram showing the secondary particle image shown in FIG.

Similar to the secondary particle image shown in FIG. 2, the beams generated by the charged particle beam device are collectively scanned on the substrate, so that the secondary particle image 20 of a relatively wide area on the substrate is obtained. To get At this time, for example, the number of pulses in the X direction of the secondary particle signal is 21 from the end of the secondary particle image 20.
By counting the number of pulses 22 in the Y direction and the number of pulses in the Y direction, the position coordinate of an arbitrary bit is obtained without moving the stage.

The number of bits can be displayed, and the number of bits displayed can have a designated area.
The display method of the number of bits can be decimal or hexadecimal display starting from an arbitrary point, and the numerical value of the arbitrary starting point is not necessarily 0 or 1, but can be designated. In addition, counting can be performed either by counting up or counting down.

As described above, according to the second embodiment, the position coordinates of the defect on the secondary particle image 20 can be obtained by counting the number of pulses of the secondary particle signal. Thereby, the image of the defect on the substrate can be accurately displayed on the output device.

Although the invention made by the present inventor has been specifically described based on the embodiments of the present invention, the present invention is not limited to the above-mentioned embodiments, and various modifications can be made without departing from the scope of the invention. It goes without saying that it can be changed.

For example, in the above-mentioned embodiment, the image information is acquired by collective scanning, but the beam is line-scanned in parallel with an arbitrary pattern on the substrate, and the secondary particle signal and the deflection voltage of the beam at that time are stored. Alternatively, the change point of the voltage contrast can be quickly obtained.

[0028]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.

A relatively short point is obtained by automatically detecting a change point of the voltage contrast indicating a defective portion from the secondary particle image obtained by batch scanning of the beam and obtaining the position coordinates of the change point from the deflection voltage of the beam. The image of the defect on the substrate can be accurately displayed on the output device in time.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a charged particle beam system according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a beam scanning direction according to an embodiment of the present invention.

FIG. 3 is a schematic diagram of image data stored in a storage medium that is an embodiment of the present invention.

FIG. 4 is a schematic diagram of an image device according to an embodiment of the present invention.

FIG. 5 is a schematic diagram showing an integration result of voltage contrasts in the X and Y directions of the secondary particle image and the entire secondary particle image according to the embodiment of the present invention.

FIG. 6 is a graph showing the relationship between the beam scanning distance on the substrate and the deflection voltage according to the embodiment of the present invention.

FIG. 7 is a schematic diagram for explaining a method of determining a voltage contrast change point according to an embodiment of the present invention.

FIG. 8 is a schematic view showing a secondary particle image which is another embodiment of the present invention.

[Explanation of symbols]

1 Charged particle beam device Two beams 3 Secondary particle signal 4 Semiconductor wafer 5 areas 6 Scan sync signal 7 Secondary particle image 8 storage media 9 monitors 10 Integration result of voltage contrast 10a change point 11 Voltage contrast integration results 11a change point 12 waveforms 13 Amplitude 14 peak intensity 15 Derivative peak intensity 16 points of change 17 Derivative peak intensity 18 Deflection voltage 19 position coordinates 20 Secondary particle image 21 Number of pulses 22 pulses

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G01R 31/302 G01R 31/28 L 4M106 (72) Inventor Yu Sekihara 5-22, Kamimizumotocho, Kodaira-shi, Tokyo No. 1 Incorporated company Hitachi Ultra LSI Systems Inc. (72) Inventor Aritoshi Sugimoto 3-16-16 Shinmachi, Ome-shi, Tokyo Hitachi Ltd. Device Development Center (72) Inventor Koike Emi 882 Ichige, Hitachinaka City, Ibaraki Prefecture, Hitachi Ltd., Instrument Group, Hitachi Co., Ltd. (72) Inventor, Toru Ishiya 882, Ichige, Hitachinaka City, Ibaraki Prefecture, Ltd. (72) Inventor, Kei Umemura, Tokyo 1-280, Higashi Koigakubo, Kokubunji-shi, Central Research Laboratory, Hitachi, Ltd. (72) Inventor Akira Shimase Yoko Kanagawa 292, Yoshida-cho, Totsuka-ku, Hitachi, Ltd., Production Engineering Laboratory, Hitachi, Ltd. (72) Inventor, Junzo Higashi, 292, Yoshida-cho, Totsuka-ku, Yokohama, Kanagawa Prefecture, Ltd., Production Engineering Laboratory, Hitachi, Ltd. (72) Yuichi Hamamura, Kanagawa 292, Yoshida-cho, Totsuka-ku, Yokohama-shi, Ltd. Inside the Hitachi, Ltd. Institute of Industrial Science (72) Inventor Satoshi Tomimatsu 1-280, Higashikoigakubo, Kokubunji-shi, Tokyo F-Term, Hitachi Central Research Laboratory, 2F065 AA03 AA49 BB13 CC17 CC19 DD06 FF04 GG04 HH04 MM11 QQ13 QQ24 QQ27 QQ31 SS02 2F067 AA54 AA62 BB01 CC17 EE10 GG06 HH06 JJ05 KK04 QQ02 RR12 RR20 RR21 RR25 RR29 SS15 2G001 AA05 BA06 CA05 GA01 GA09 HA01 KA03 LA11 MA05 2G011 AA01 AC11 AE03 2G132 AA00 AC03 AD15 AE08 AE14 AE16 AE18 AE23 AF12 AF13 AL09 AL11 4M106 AA01 BA05 BA20 CA38 DB30 DJ11 DJ12 DJ13 DJ18 DJ21 DJ23

Claims (6)

[Claims] 1. A change point of voltage contrast is automatically detected by a calculation process from a secondary particle image obtained by collectively scanning a beam on a substrate in an image type defect inspection step,
A method of manufacturing a semiconductor device, wherein a defect image is displayed on an output device using the position coordinates of the change point obtained from the deflection voltage of the beam. 2. In the image-type defect inspection step, the position coordinate of an arbitrary bit is obtained by counting the number of pulses of a secondary particle signal obtained by scanning a substrate with a beam at once, and the position coordinate is used. A method for manufacturing a semiconductor device, comprising displaying a defect image on an output device. 3. In the image-type defect inspection step, a change point of voltage contrast is automatically detected by a calculation process from a secondary particle image obtained by collectively scanning a beam on a substrate,
A method of manufacturing a semiconductor device that displays a defect image on an output device using the position coordinates of the change point obtained from the deflection voltage of the beam, wherein the position coordinates obtained from the secondary particle image and the deflection voltage of the beam are And a method of manufacturing a semiconductor device, which is stored in a storage medium. 4. In the image-type defect inspection step, a change point of voltage contrast is automatically detected by a calculation process from a secondary particle image obtained by collectively scanning a beam on a substrate,
A method of manufacturing a semiconductor device, wherein a defect image is displayed on an output device by using position coordinates of the change point obtained from a deflection voltage of a beam, wherein all voltage contrasts in the X direction and the Y direction of the secondary particle image are displayed. The integrated result, the integrated result of all voltage contrasts in the X and Y directions of the secondary particle image, or the calculated voltage contrast of one scan line in the X and Y directions of the secondary particle image, respectively. The method for manufacturing a semiconductor device, wherein the change point is detected from the result. 5. In the image-type defect inspection step, a change point of voltage contrast is automatically detected by a calculation process from a secondary particle image obtained by scanning a substrate with a beam at once.
Using the position coordinates of the change point obtained from the deflection voltage of the beam, a method of manufacturing a semiconductor device for displaying a defect image on the output device, wherein the change point, when the calculation result of the voltage contrast is a waveform, The semiconductor device is characterized by being determined by the amplitude, peak intensity or differential peak intensity of the calculation result, and when the calculation result of the voltage contrast is other than a waveform, it is determined by the change point or differential peak intensity of the calculation result. Manufacturing method. 6. In the image-type defect inspection step, a change point of voltage contrast is automatically detected by a calculation process from a secondary particle image obtained by collectively scanning a beam on a substrate,
A method of manufacturing a semiconductor device that displays a defect image on an output device using position coordinates of the change point obtained from the deflection voltage of the beam, wherein the beam is an ion beam. .