WO1999028964A1

WO1999028964A1 - Method for producing electronic device and foreign matter analyser therefor

Info

Publication number: WO1999028964A1
Application number: PCT/JP1998/005439
Authority: WO
Inventors: Hidefumi Ibe; Kenji Watanabe; Akira Shimase; Masataka Shiba; Tsutomu Sakamoto
Original assignee: Hitachi, Ltd.
Priority date: 1997-12-03
Filing date: 1998-12-02
Publication date: 1999-06-10
Also published as: JPH11168126A

Abstract

In an electronic device production line, in order to analyze the elements of a foreign matter on a device and the cross sectional structure of the foreign matter and the periphery thereof in a short time, the material surface of the foreign matter is exposed, the elements contained in the exposed surface and the cross section around the foreign matter, the arrangement of the device elements and the thicknesses of films are analyzed, a causal apparatus which has generated the foreign matter is specified by comparing the results of analysis with the design and production information on the device, and a countermeasure is taken for the apparatus, thus producing an electronic device. Both an apparatus for exposing the cross section containing a foreign matter and an apparatus for analyzing the distributions of elements and compounds existing on a line in the plane of the foreign matter including the cross section containing the foreign matter are arranged on the production line as a foreign matter analyzer. The step, process or apparatus causing a defect due to a foreign matter in a large-scale integrated electronic device can be specified in an extremely short time, and the production line can be started in a short time while maintaining high yield mass production.

Description

Description: ELECTRONIC DEVICE MANUFACTURING METHOD AND PARTICLE ANALYZER

The present invention relates to a method for manufacturing a semiconductor device in a production line required for early start-up of the yield of semiconductor devices such as a memory, an ASIC or other LSI, a magnetic disk device, a liquid crystal, etc. About. Background art

In the early stages of startup of semiconductor devices, there are many so-called process defects due to misalignment of patterns in one lithography step. On the other hand, even after the process defects have been improved, the yield of semiconductor devices is at most 70%, which is not sufficiently high. This is attributed to foreign matter in the semiconductor device production process.

The process of a semiconductor device can be divided into several hundred steps if it is subdivided in units of equipment, and foreign matter 6 generated during the manufacturing process is usually the same as that of a film 8 formed in a certain process, as shown in FIG. The film 7 that adheres to the upper surface and is formed in the next process is formed on the foreign material 6. Further, since the films formed in the subsequent steps are stacked, foreign substances are often present in a state of being sandwiched between several films. Defective semiconductor devices are usually subjected to quality inspection at the stage where they have a single function, such as after the completion of a wiring process. In memory devices, devices that detect bad bits are often used for this purpose. However, even if a foreign substance corresponding to such a defective bit is confirmed from the upper part, since a large number of films are formed on the foreign substance by processes subsequent to the generation, the abnormalities are different. It is not possible to identify the process of generating foreign substances and the equipment simply by confirming the position from the top of the object, observing the appearance, and elemental analysis.

On the other hand, during each individual intermediate process, appearance inspection using SEM, element measurement, or appearance inspection using an optical method, and inspection using a foreign object inspection device that detects the position and approximate size of foreign objects using scattered light are performed. Information about the detected foreign matter is stored in a database. However, it is almost impossible to confirm the generation of foreign matter in such an intermediate process in all the detailed processes, considering the required time.Therefore, the above inspection is intermittent as long as the overall process time is not unnecessarily extended. Is applied. If a large number of foreign substances are generated or fatal in a certain range of processes, countermeasures will be considered. As the original procedure, all possible factors are extracted, test conditions that can be evaluated for each of these factors are selected and implemented, and based on the results, the optimal process conditions and causes are narrowed down. It should be.

However, in practice, it takes about 10 steps between foreign particle inspections, that is, equipment is interposed, and considering that there are various operating conditions for each equipment, all possible conditions are tested. Is virtually impossible to implement. Therefore, as shown in Fig. 3, based on the technician's experience, we added an additional process such as ultrasonic cleaning after a certain device C, and saw the results. Tests in which the conditions were changed were successively performed, and if good results were obtained, they would be applied for the time being.However, because this was not a measure that took a clear grasp of the cause, the process conditions were somewhat It is impossible to anticipate the occurrence of a large amount of foreign matter when it changes, and to respond in advance. In some cases, foreign matter analysis is performed offline to determine the cause, and countermeasures are taken.However, analyzing a large number of foreign matters and identifying the cause based on the results often takes a very long time. This is a necessary task. In any case, the process range where foreign matter is generated is limited to some extent Yes, but it is extremely difficult to quickly identify equipment and take effective measures.

In the above inspections, component analysis of foreign substances is not usually performed. This is a because it takes time to component analysis, many foreign substances, such as _{S i 0 2, A 1,} W particles, in the film forming material is largely used in the flop opening processes, merely analyzing, in Figure 2 As shown, film formation components on foreign matter appear after the occurrence, so it is difficult to identify the process, equipment, and causative substance of the foreign matter, and even if the analysis is troublesome, analysis can provide definitive information. It is also because the probability is low. If a foreign substance inspection is always performed after each deposition step, the generator can be identified, but the throughput is extremely low. To remedy this, for example, it is necessary to remove the film that normally exists on the foreign material after the occurrence and expose the outermost surface of the foreign material. This operation takes time and requires certainty. poor. To save time in the operation with this, as a means for exposing the device cross-section using a FIB (Focused Ion Beam focused ion beam method), in S EM drilling surface from an oblique _{(Scanning E 1 ectro nM icrosc 0} pe) A means for observing is proposed in Japanese Patent Application Laid-Open No. H11-189529.

In this method, if the SEM is accompanied by EDX (Energy Dispersive X-ray analysis), elemental analysis of the cross section can be performed. However, EDX has poor spatial resolution (about Ιμπι). It is extremely difficult to analyze the cross-section of a 0.1 m diameter foreign matter or a film with a thickness of about 100 to 100 nm formed in each process. With the current analytical instruments, AES (Auger electron spectroscopy), which can analyze the outermost surface with a spatial resolution of about 10 nm and depth information of about 10 A, is considered to have met the purpose.

On the other hand, even if the above method can analyze foreign matter and the elements and compounds of the films above and below the foreign matter, the foreign matter generator cannot be specified. In order to identify the generator, it is necessary to further cope with the film formation process, In some cases, it is necessary to determine by analyzing the film before the second and third steps. If the film element structures before the generation of foreign matter are arranged in the order of, for example, FGH, it is necessary to extract and determine the steps in that order from a database on processes. Once the foreign matter generation process has been identified in this way, the next step is to trace the history of the wafer and use the equipment used in the relevant process (it is often necessary to use multiple equipment in the same process, so it is necessary to identify which equipment There is. The above analysis also requires a long time.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method of manufacturing a high-yield electronic device and a foreign-matter analyzing apparatus for the same, which can identify a cause and a generator of foreign matter on a semiconductor device during manufacture within one day. Disclosure of the invention

In the present invention, the following are the basic components in order to be able to specify the cause of generation of foreign matter on a semiconductor device and the device in a short time.

(1) Install an initial analyzer (analysis station) on the semiconductor production line.

(2) The initial motion analyzer includes a device for exposing a cross section of a foreign substance of a device and a device for specifying a constituent element and a structure of a film adjacent to the foreign substance cross section and the foreign substance.

(3) Based on the cross-section of the foreign material, the upper and lower structures including the foreign material, the surrounding structure, material information and design, and the manufacturing history of the device, a process for generating the foreign material and supporting software and a database that enable rapid identification of equipment are provided. Included in the production management system. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram showing the general concept of the present invention, and FIG. FIG. 3 is a diagram showing an example of a cross section of a device including foreign matter. FIG. 3 is a diagram showing an example of a current state of a foreign matter separating procedure of a semiconductor device. FIG. 4 is a diagram showing a cause of foreign matter generation in a semiconductor device. FIG. 5 is a diagram showing an example of a configuration of an initial analyzer required for short-time identification of the device. FIG. 5 is a diagram showing a top view of one embodiment of an initial analyzer according to the present invention. FIG. 6 is a diagram showing a side view of one embodiment of the initial analysis apparatus according to the present invention. FIG. 7 is a view showing a side view of one embodiment of the initial analysis apparatus according to the present invention. FIG. 8 is a diagram showing the overall appearance of an embodiment of the initial motion analyzer according to the present invention, and FIG. 9 is a diagram showing one of the positional relationships between the AES and the FIB sample according to the present invention. FIG. 10 is a diagram showing one of the positional relationships between the AES and the FIB sample according to the present invention, and FIG. 11 is a diagram related to the present invention. Fig. 1 shows one of the positional relationships between the samples excavated by AES and FIB. Fig. 12 shows the relationship between the incident angle of ions and the sputter efficiency. Fig. 13 The figure is a diagram showing one of the positional relationships between AES and FIB according to the present invention, and FIG. 14 is a diagram showing one of the positional relationships between AES and FIB according to the present invention. Fig. 15 shows the method of returning foreign matter to the focus of FIB and AES when the stage is rotated.Fig. 16 shows the integration of AES and FIB. FIG. 17 is a diagram showing the positional relationship of each part in the apparatus from the top and the side. FIG. 17 is a diagram showing the arrangement of shirts for preventing AES contamination by FIB. The figure shows the support structure of the equipment that assists accurate alignment when FIB and AES are used in a single container.Fig. 19 shows the case where FIB and AES are used in a single container. Wafer FIG. 20 is a diagram showing an outline of a vacuum container for simplifying loading and unloading, and FIG. 20 is a diagram showing an embodiment of the initial motion analyzer according to the present invention. Fig. 21 shows an example when LI MS-TOF is used. Fig. 21 shows an example of a computer screen for registering a film formation structure in the coordinates of foreign particles. Fig. 22 Is different Fig. 23 shows an example of a computer screen that assists in analyzing a film formation structure in object coordinates. Fig. 23 shows a computer screen that assists in analyzing a film formation structure in foreign object coordinates. FIG. 24 shows an example of a computer screen that uses the foreign matter generation process / apparatus for specific support. BEST MODE FOR CARRYING OUT THE INVENTION

In the present invention, a wafer is assumed as a semiconductor device for simplicity. The present invention can be similarly applied to magnetic disks other than wafers and thin film transistors (FT).

In the present invention, as shown in FIG. 1, the system configuration is as follows.

(1) The first-movement analysis station 1 is located adjacent to the production line to save time during wafer transfer and to prevent foreign substances from adhering unnecessarily during wafer transfer.

(2) The initial motion analyzer can measure the structure and element distribution of the device cross section including foreign matter.

(3) The system includes software that analyzes or supports analysis of the film formation structure at arbitrary coordinates of the device.

In a semiconductor device production system based on the above system configuration, this system can be applied to a prototyping line as well, and it is possible to eliminate defects caused by foreign matter and foreign substances at an early stage. In the example shown in Fig. 1, starting from the initial process 5 of the device, the process is set by the analysis station 1 linked to the optical particle inspection device 2 several times during several hundreds of detailed processes. The foreign substance inspection device 2 obtains in advance the size and coordinates of the foreign substance, cluster information (characteristics of the arrangement of the foreign substances), and the like, and then performs analysis. This information is Of course, it is necessary to locate the object, but it is a source of information for selecting foreign substances to be analyzed.

In the example shown in Fig. 1, first of all, foreign substances are checked using the SIM (Scanning Ion Microscope) attached to the SEM or FIB. And take action on the generated device 4. By accumulating data on the appearance of foreign matter, it can be expected that the cause, process, and equipment of the foreign matter can be identified only by the appearance. Next, excavation is performed with FIB so that the cross section of the foreign material is exposed, and a cross section image is obtained. Similarly, in some cases, the cause, process, and equipment of the foreign matter can be determined only by the foreign matter and the surrounding film structure. It is also possible to select a foreign object to be excavated by the FIB from the appearance image and the information of the foreign object inspection device 2. If the cross-sectional image alone cannot identify the process, equipment, and causative substance of the foreign substance, perform elemental analysis of the foreign substance and / or elemental analysis of the adjacent film, and refer to the database on the film formation process and equipment information. Identify the process, equipment, and causative substance of the foreign matter. In order to carry out the analysis efficiently and, in some cases, to return the analysis wafer to the production line, it is desirable that the wafer can be put on the entire sample stage without being divided. In the case of DRAM, the wafer size is currently 20 cm to 30 cm in diameter, and the sample stage is desirably 30 cm in diameter or more. With this size, the magnetic disk is less than 10 cm in diameter and can be analyzed as is. Currently, liquid crystal displays have a diagonal length of 12 or 13 inches, so a sample stage of about 30 to 35 cm can be used. As the size is expected to increase further in the future, the size of the stage must be correspondingly increased.

The procedure for analyzing foreign matter according to the present invention will be described with reference to the cross-sectional structural view of the semiconductor device shown in FIG. While confirming the cross section with SEM, the foreign material cross section 6 and the surrounding film structure are exposed by FIB. As mentioned earlier, the spatial resolution AES is used as the elemental analyzer because of the limitations. The elemental analysis on the line 9 including the foreign matter 6 and the upper and lower films 7 and 8 is performed by AES, and the constituent elements of the foreign matter 6 and the components of the upper and lower films 7 and 8 are measured. In this way, the material, thickness, etc. of the films 7 and 8 above and below the foreign matter 6 are known. I understand. The equipment used in the relevant process can be specified from the history record of the wafer, and the operating conditions of the equipment can be found. Since the AES line analysis takes time, three points analysis of the foreign material 6 and one point in the cross section of the upper and lower films 7 and 8 may achieve the purpose in some cases.

Hereinafter, details of the present invention will be described in terms of hardware. One embodiment of the analyzer according to the present invention is shown in FIG. In the embodiment, the FIB 10 and the AES 11 are separated from each other, and the two can be isolated by the gate valve 12. The wafer is first set in the load mechanism 13, vacuum-evacuated in advance, the gate valve 12 is opened, the wafer is introduced into the processing chamber 23 for the FIB 10, and after being positioned in the stage drive mechanism, Observe the appearance using the SIM function provided with SEM14 or FIB10. In the present invention, the stage drive mechanism is premised on XY Z three-axis drive unless otherwise specified. The positional relationship between the FIB column 10 and the SEM column 14 is adjusted in advance so that the electron beam is focused on the processing point by the FIB. For this reason, it is possible to monitor the progress of the processing at a certain frequency during the processing of the cross section in the FIB and monitor the progress of the processing to determine the processing end point with high accuracy. An infrared heater 19 is installed in the loading mechanism 13 so that the wafer can be baked if necessary. After that, the wafer was opened with the gate valve 12 between it and the AES 11, introduced into the analysis chamber 28 for the AES 11, and positioned, and then, if necessary, cut out with the ion gun 17. Adsorbed atoms are removed, and cross-section observation and elemental analysis are performed using the SEM function attached to AE S11. In this case F Since the hole is drilled vertically in IB10, AES is attached to the vacuum container 28 diagonally so that the cross section can be seen. In the example shown in the figure, the AES is a form that uses a combination of the SCA for the electron gun 21 and the detector. After the measurement is completed, it is pulled out of unload chamber 20 and moved to the next process or locked out. In the case of the example in Fig. 4, since the analyzer is a separate container, AES, which requires a particularly high degree of vacuum, has good maintainability, such as maintaining the degree of vacuum, but requires only two positions on the stage. Times needed. However, it is easy to detect relatively large holes drilled by the FIB in the analysis chamber, and this is not an essential minus.

Another embodiment in which the FIB column 10 and the AES column 11 are installed in different chambers is shown in FIGS. 5 and 6. In this case, the wafer to be analyzed introduced from the loading chamber 13 is introduced into the processing chamber 23 via the gate valve 12 and is usually placed at a plurality of predetermined positions by the FIB 10. Cross-section processing is performed. During FIB processing, electrons are irradiated from the electron shower 25 to the region including the ion beam irradiation region in order to avoid movement of the processing position due to accumulation of ion charges. At this time, secondary ions generated by ion beam irradiation are detected to obtain a surface unevenness image of the processing object, but when an SEM image is obtained with the electron beam from the SEM column 14, secondary electrons are detected. The secondary particle detector 24 can detect both secondary ions and secondary electrons.For example, a scintillator and a photomultiplier tube are installed in a channeltron, microchannel plate, or microphone channel plate. The structure of the detector combined is taken. The wafer for which the cross-section processing has been completed moves to the analysis chamber 28 via the gate valve 12 next. The CMA-type detector used as the AES lens tube 1 is equipped with electron beam focusing and scanning functions. Analyze target by detecting with secondary electron detector 27 The SEM image is obtained, and it is used to perform beam positioning to the analysis position after moving to the predetermined position on the stage. Therefore, the analysis chamber 28 is equipped with a rare gas ion gun 26 to remove a natural oxide film or the like covering the surface to be analyzed. Next, the object to be analyzed is irradiated with an electron beam by AES 11 and analyzed. This operation is repeated for a plurality of specified locations, and the analysis data acquisition ends. After that, the wafer is taken out to the loading chamber 20 via the gate valve 12. The above is the processing / analysis process in the apparatus of the present embodiment.

One of the advantages of this embodiment is that the AES analysis in the analysis chamber 28 requires an ultra-high vacuum, but the processing chamber 23 does not require an ultra-high vacuum. This reduces the load on the processing chamber 23 to vacuum. This reduces the restrictions on having a drive in the processing chamber 23 內. Further, processing can be advanced in the processing chamber 23 while the analysis is being performed in the analysis chamber 28. Furthermore, since the chamber is evacuated to a vacuum inside the processing chamber 23, it is evacuated for the time required for processing before the wafer is introduced into the analysis chamber 28.ゥヱ C can be introduced, and there is no need to provide a preliminary evacuation time until degassing from the sample, which is usually required in ultra-high vacuum, is reduced. The total time required for these rework and analysis processes can be reduced. In the present embodiment, the loading chamber 20 is also provided on the analysis chamber 28 side at the time when the analysis in the analysis chamber 28 is completed. This is because the wafer cannot be taken out to the processing chamber 23 side because the holder on which the wafer is placed is inserted. However, when returning the processed wafer to the line after processing and analysis, it may be necessary to refill the processing traces. At this time, the next item is not put in the processing chamber 23, but is added from the analysis chamber 28. It is necessary to return to ethiamba 23. In this case, an improved device configuration is shown in the following embodiment. Another advantage of the present embodiment is that since an ultra-high vacuum is not required for the processing chamber 23, the etching gas and the deposition gas are supplied from the gas supply device 22 to the processing chamber 23 via the nozzle. In addition, it is possible to increase the processing speed and implement backfilling.

In the above embodiment, the next wafer cannot be introduced into the processing chamber 23 in order to backfill the processing trace, and the advantage of using another chamber is partially lost in that case. Therefore, the device configuration shown in FIGS. 7 and 8 was adopted. Here, in the embodiment shown in FIGS. 5 and 6, the loading chamber 13 was provided on the side of the analysis chamber 23, but this was eliminated, and the standby chamber 31 was provided at the end of the processing chamber 23. The system was provided. With this method, the wafer after the analysis is returned to the processing chamber 23, and when backfilling the processing traces, the wafer that has been processed in the processing chamber 23 is transferred to the temporary standby chamber 31. The wafer having been analyzed is moved from the analysis chamber 28 to the processing chamber 23, and is introduced into the mouthing chamber 13 via the gate valve 12 as it is. Next, the stage is moved below the evacuation chamber 31, the evacuation wafer is lowered, and introduced into the analysis chamber 28 via the gate valve 12. Then, the analyzed wafer is returned from the loading chamber 13 to the processing chamber 23 and backfilled. During that time, the analysis of the introduced wafer is being performed in the analysis chamber 28 2. Here, the wafer once returned to the processing chamber 23 is further moved to the loading chamber 13, but in order to avoid this, a chamber similar to the retraction chamber 31 is also provided on the analysis chamber 28 side. It is sufficient to transfer the wafer between the evacuation chambers, but the analysis chamber 28 is a chamber that requires an ultra-high vacuum. Considering avoiding the provision of a force mechanism, this time it took time and effort to move, but the priority was given to maintaining an ultra-high vacuum, and this method was adopted. In this method, the loading chamber that is temporarily released to standby is not installed on the analysis chamber 28 side, and the analysis chamber 28 is always evacuated and is opened only to the processing chamber 23. Therefore, the ultrahigh vacuum of the analysis chamber 28 is easier than in the above embodiment.

The CMA in the analysis chamber has strict restrictions on the distance from the sample (working distance), and the z-axis is usually adjusted by adjusting the stage height to the position where the secondary electron yield is highest. However, it is possible to assist the Z-axis positioning mechanism by providing the Z-axis stage with a positioning mechanism based on the electric capacity and the scattering direction of light.

Fig. 9 shows FIB 10 and AES 11 housed in the same container without a separating wall such as a gate valve. For simplicity, the enclosure and wafer of FIB 10 and AES 11 are shown. Only the positional relationship of 4 is shown. The advantage is that the time and complexity of moving between containers in the case of FIGS. 4 to 8 can be avoided. In the example of Fig. 9, FIB 10 and AES 11 are arranged at a fixed interval, and after the FIB 10 exposes a vertical cross section of the foreign matter, the movement amount is known when measuring AES 11 At a distance of, the position of the foreign matter is aligned on the optical axis of the AES 11 and the cross section of the foreign matter is obliquely inclined to AES 11 for observation and analysis. In this case, extra time is required for positioning, but there is ample room for the layout of FIB 10 and AES 11 and the design becomes easier. The advantage is that atoms that are sparsely packed by 0 are less likely to contaminate the surroundings, including AES.

FIG. 10 is a view showing another embodiment. In order to focus on the same foreign matter at the same time, make sure that the CMA type AES 11 and the tip of the FIB 10 are not in contact with each other. 1 and FIB 10 are both tilted from the surface of wafer 4. You. In this case, there is a difficulty in accurately focusing both on the foreign matter, but even when using the SEM function as shown in Fig. 11, the excavation surface 34 and the foreign matter 6 can be seen from just above the cross section. The observable point, as well as the foreign matter and the surrounding structure, are cut obliquely, so that they have the advantage of being enlarged in the depth direction and easy to see. This can be realized by arranging the optical axis of the FIB 11 and the optical axis 33 of the incident electron of the AES so that the optical axis is approximately 90 °. Actually, the excavation surface of the FIB is duller than the optical axis of the ions, so making it 90 ° or 5 ° narrower makes the actual surface directly opposite AES.

As shown in FIG. 12, the tilt angle of FIB is preferably 30 ° or more and 90 ° or less, more preferably about 60 °, with respect to the vertical direction from the viewpoint of sputtering efficiency. Also, if the angle is 60 °, the cross section is doubled, which is advantageous in evaluating the film structure. This arrangement has a large time-saving effect in that there is no movement between the beam axes of the analyzer and only one alignment with the foreign matter is required.However, atoms sputtered by the FIB can damage the AES electrodes and the surface of the structure. It may contaminate, change properties and deteriorate.

FIG. 13 shows an arrangement in which FIB 10 and AES 11 form a right angle when viewed from above while maintaining the inclination of FIB 10 and AES 10. With this arrangement, in addition to the advantages of easy alignment and high sputter efficiency, the point at which an image of the vertical cross section 35 can be obtained is analyzed through the cross section of the contact hole. It will be advantageous in the case.

Fig. 14 shows an arrangement between Fig. 10 and Fig. 13 where the FIB 10 optical axis is taken from a direction of 135 ° with respect to the AES 11 optical axis. Although it is not possible to confront the cut surface, there is an advantage in that both sides 34 and 35 can be analyzed at once. In the case of AES 11, an ultra-high vacuum is required, so it is desirable to avoid installing a complicated driving mechanism inside the vacuum vessel as much as possible. However, if a rotating mechanism around the Z axis is provided on the stage, Vertical section 35, oblique section It is possible to analyze both 3 and 4.

By adding a rotation mechanism to the stage, it is possible to observe both oblique and vertical machining surfaces, regardless of the angle between the optical axis of the FIB and AES mapped to the horizontal plane. If you rotate a new object and observe it again while observing a certain foreign object, simple coordinate conversion is performed and the foreign object is automatically aligned with the analysis point. Fig. 15 summarizes such a method of positioning foreign objects when the rotary stage is mounted on the XYZ stage. That is, suppose that the coordinates of the center of rotation are (X 0, Y 0) with respect to the foreign object coordinates (X, y) defined on the XY stage. The angle formed by the mapping of the optical axes of FIB and AES onto the horizontal plane. At this time, if the rotary stage is rotated πΖ2-α counterclockwise, the vertical side surface of the borehole can be observed from the AES in the front direction. However, in this state, the foreign matter has moved far away from the focal point of the FIB and AES. Therefore, if the stage is moved in the X and Y directions by the following distance, the foreign matter returns to the focal point.

X direction: X — X. — D cos (α + y)

Υ direction: y—Υ. ― Dsin (a + 7)

Where d = ((x-Xo) ² + (y-Yo) ² ) ^1/2

FIG. 16 conceptually shows the whole image of the apparatus in the case of FIG. 10. The wafer is transferred from the wafer case 39 to the loading chamber 13 and the main chamber 37 by the wafer introduction mechanism 42. Automatically introduced.

As described above, when FIB 10 is provided in the vicinity of AES 11, there is a concern that irradiated ions of FIB or ions resputtered by the irradiated ions may contaminate the detector portion of AES and change its characteristics. is there. Fig. 17 shows an example in which a shutter 45 is provided at the end of the AES 11 to avoid such contamination of the AES 11, and the shutter 45 is connected to the AES 11 during excavation with the FIB. Orange (4) Install it so as to cover the electron inlet, and in the case of AES, rotate the rotating port (44) to enable AES analysis.

Both the FIB and AES barrels are heavy, and usually have ion pumps, so operability must be devised to match the optical axes of both. Figure 18 shows an example of such a device. The main body of the FIB is supported by a column 47, and a bellows 48 is provided in the middle so that the shaft position can be changed, and the optical axis is adjusted at the position of the bolt 49. At this time, the ion pump 46 is supported by another support column 47 so that the weight of the ion pump 46 is not burdened, and the ion pump 46 is connected to the FIB main body 10 by a bellows 49.

Fig. 19 shows a modified example of the mouth mechanism when FIB 11 and AES 11 become a body container. Open 1 and do it manually. A wafer chuck mechanism can be provided for automation. In the same figure, for example, a wafer is introduced into the load lock chamber in the foreground, and is evacuated once while being baked with an infrared lamp or the like as necessary, and then introduced into the measurement chamber 37. After drilling, analyze with AES11. The optical axis of the optical microscope 40 does not coincide with AES 11 and FIB 10, but is effective for confirming the positional relationship between the foreign object and the peripheral devices in advance.

Fig. 20 shows a conceptual diagram of the equipment when LIMS-TOF (Laser Induced Time-of-Flight Mass Spectrometer) is used instead of AES. A pilot beam using a He-Ne laser beam or the like is applied to a specific position, and a laser beam for abrasion (for evaporating and ionizing foreign matter) is incident on the same position from the beam introduction window 60 and the objective lens 6 1 Focus on foreign matter on 3 2. Part of the foreign matter is ionized, accelerated by the extraction electrode 52, and relocated by the orbit deflection electrode 54. After deflecting the orbit, it enters the flight tube 58, and by measuring the time of flight, the mass-Z charge ratio of the region (proportional to the square of the time of flight) can be determined. Compared to the case where AES 11 is used, this method can obtain information on the structure of organic substances and isotopes, and is characterized by a large amount of information. Regarding the degree of vacuum, AES 11 requires a degree of vacuum of 10-8 Pa, whereas the order of 10-4 Pa is sufficient, so that maintenance is easy. is there. Also, since the laser is a probe, there is no charge on the sample, which is advantageous when measuring insulators and organic substances. On the other hand, since foreign matter is a destructive inspection, it is not suitable for line analysis and repeated measurement such as EDX.

With the above device configuration, data on the constituent elements and structure of foreign matter and the film structure near the foreign matter can be obtained. The basic concept for identifying a foreign matter generator is the same as described above, but even if there is data, it takes several days or more to identify the generator unless special measures are taken. This is because the following databases are required for identification, and it takes one day each to extract the necessary information from each. .

(a) Foreign material coordinates and film formation conditions in the vicinity (material, thickness)

(b) Wafer history (applied process, equipment (including unit), process conditions)

(c) Process for each product (material used, film thickness)

(d) Equipment specifications and properties (constituent materials, actual generated foreign substances)

For database (a), the following databases are required.

(e) 3D pattern information of device (size of film, line width, material, thickness, etc.)

The following describes in detail the process of generating foreign substances based on the results of the analysis by the initial analysis equipment group and the above-mentioned database group, the equipment, and the method for quickly identifying the causative substance.

Database ( _e ) is difficult to maintain directly as a database Peri, not easy to use. This is because not only does the capacity itself become enormous, but also because of the frequent changes associated with process improvements, an enormous amount of time is required for database maintenance. In the present invention, the database (e) relating to the materials on the individual devices is constructed by registering each element, not each coordinate. A specific construction method will be described with reference to an example of a computer screen shown in FIG. Fig. 21 shows the screen assuming software built with Visua 1 Basic, but the following functions can be realized in other software development environments as well. In the example of Fig. 21, the device base Y, product, and process ID are specified, then the deposition process AA is specified, and then the materials used in the process of forming the corresponding element are listed A. Select from C to F from ~ F, and enter and register the film thickness.

Next, a device pattern image is displayed on the screen as shown in Fig. 22 in order to identify the elements that originally exist above and below the foreign matter, and the operator is informed of the foreign matter position and what elements are arranged in the vicinity thereof. Specify. The operator registers elements above and below the foreign object in the foreign object coordinates as A and B from the lists A to G. If the element can be specified, the material and thickness for each element are

Since it is registered in (e), information on the material and thickness at the position of the foreign matter when there is no foreign matter can be known. On the other hand, cross-sectional SEM images, upper and lower film materials including foreign substances, and thickness analysis results obtained by AES or EDX have been obtained. If the cross-sectional SEM image and element distribution information obtained in the analysis (in the example in the figure, the line analysis results on line 9 containing foreign matter using AES) can be compared on the same screen, the process of foreign matter generation can be identified. . Even if the film structure is not strictly reconfigured for each element, it is used in the process, including harmful materials that are not actually located at the position of foreign matter due to etchback, gas components contained in the plasma, or resists. Virtual material layered from below The process of generating foreign matter can be specified to some extent only by illustrating the typical film structure. A film cannot be formed by the plasma process, and the resist is a thick film formation process with a thickness of several μm, but it does not remain on the product in principle. Therefore, it is preferable to give these processes a virtual thickness (for example, 100 nm) and display them on the screen. In such a method, when a reaction product with the plasma gas or a reaction product with the resist is generated, the process is visualized on a screen, which is advantageous in identifying the cause process. is there. On the screen, both the strict evaluation result of the layer structure and such a virtual film structure diagram may be displayed. If the generation process of such a foreign substance can be specified, the re-generation device can be specified by the history database (b) of the wafer, and the re-generation source can be specified by the database (d).

Furthermore, if the composition, structure, generation process, and equipment of the foreign matter are clarified, the support tool as shown in Fig. 24 will be used to determine the constituent elements and structure of the foreign matter, the materials used for the relevant equipment, and the results of the generated foreign matter. By comparison, it is possible to quickly identify the causative substance, the cause of occurrence, and the countermeasure of the foreign substance. Industrial applicability

ADVANTAGE OF THE INVENTION According to the present invention, it is possible to ultimately analyze a defect caused by a foreign substance in an electronic device such as a highly integrated semiconductor device in a short time. This makes it possible to maintain mass production of fasteners, and is extremely suitable for the manufacture of electronic devices.

Claims

The scope of the claims

1. Exposing the material surface of the foreign matter, analyzing the elemental composition and the element arrangement and film thickness of the exposed surface and the cross section around the foreign matter, and comparing them with the device design and manufacturing information. A method for manufacturing an electronic device, comprising: specifying an apparatus for generating foreign matter; and taking measures against the apparatus to manufacture an electronic device.

2. The method for manufacturing an electronic device according to claim 1, wherein the analysis includes: a foreign substance having a diameter of 1 angstrom or more and 20 μππι or less centered on the foreign substance; A method for manufacturing an electronic device, comprising analyzing one of materials.

3. The method for manufacturing an electronic device according to claim 1, wherein the material surface of the foreign substance is a cross section of a foreign substance.

4. The method for manufacturing an electronic device according to claim 1, wherein the analyzing comprises analyzing a distribution of elements and compounds on a line passing through a plane of the foreign matter. Manufacturing method.

5. The method for manufacturing an electronic device according to claim 1, wherein the analysis includes determining a distribution of an element or a compound at a position including a cross section of the foreign substance, and a film cross section immediately above and immediately below the foreign substance. A method for manufacturing an electronic device, characterized by analyzing.

6. An electronic device characterized in that both a device for exposing a cross section containing foreign matter and a device for analyzing the distribution of elements and compounds on a line passing through the surface of the foreign material in the cross section containing foreign matter are included in the production line. manufacturing device.

7. Exposing the material surface of the foreign matter, analyzing the elements included in the exposed surface and the cross section around the foreign matter, arranging the elements, analyzing the film thickness, and designing the device. A manufacturing apparatus used in an electronic device manufacturing method for manufacturing an electronic device by identifying a foreign matter generating apparatus by comparing the manufacturing information with the manufacturing information and taking measures against the foreign matter generating apparatus. An analysis station that has three types of analyzers in the same container: a device that acquires the cross-sectional image of the foreign material, and a device that performs chemical analysis of the foreign material and at least the film formation adjacent to the foreign material. An electronic device manufacturing apparatus characterized in that a device is provided.

8. Exposing the material surface of the foreign material, analyzing the element contained in the exposed surface and the cross section around the foreign material, analyzing the arrangement of elements and the thickness of film formation, and comparing it with the device design and manufacturing information. A manufacturing apparatus used for an electronic device manufacturing method for manufacturing an electronic device by specifying an apparatus for generating foreign matter and taking measures against the apparatus, wherein the apparatus exposes a cross section including the foreign matter, and includes a foreign matter. It includes both a device for analyzing the distribution of elements and compounds on a line passing through the surface of a foreign substance in a cross section, and the device is provided under the same vacuum condition in a partition wall separated from the atmosphere. Electronic device manufacturing equipment.

9. Exposing the material surface of the foreign matter, analyzing the elements included in the exposed surface and the cross section around the foreign matter, analyzing the arrangement of elements and the thickness of film formation, and comparing with the device design-manufacturing information. A manufacturing apparatus used in an electronic device manufacturing method for manufacturing an electronic device by specifying an apparatus for generating a foreign substance and taking a countermeasure for the apparatus, wherein the focused ion beam apparatus and a section including the foreign substance are included in the surface of the foreign substance. An apparatus for manufacturing an electronic device, comprising: an apparatus for analyzing the distribution of elements and chemical bonds on a line passing through a device; and wherein the apparatus is provided under the same vacuum condition that is isolated from the atmosphere. 10. Exposing the material surface of the foreign matter, analyzing the element contained in the exposed surface and the cross section around the foreign matter, analyzing the arrangement of elements and the thickness of film formation, and setting the device. A manufacturing apparatus used in a method of manufacturing an electronic device, wherein a device for generating a foreign substance is specified by comparing with the manufacturing information, and a measure is taken for the device to manufacture an electronic device. Manufacturing an electronic device, including both an apparatus and an Auger electron spectrometer, wherein the apparatus is deployed under the same vacuum conditions isolated from the atmosphere.

1 1. FIB column, SEM column, secondary particle detector, electron shower, sample stage and processing chamber on which the vacuum exhaust system is mounted or connected, AES column, rare gas ion gun, secondary electron detector A foreign matter analyzer for an electronic device, wherein a sample stage and an analysis chamber on which a vacuum exhaust system is mounted or connected are connected via a gate valve.

12. The foreign matter analyzer for an electronic device according to claim 11, wherein the FIB ion orbit axis is tilted by 30 ° or more and 90 ° or less with respect to a vertical upper part of the analysis sample. Foreign matter analyzer for electronic devices. 13. A foreign substance analyzer for an electronic device according to claim 12, wherein the focal length of the FIB ions is variable.

14. In the foreign matter analyzer for an electronic device according to claim 11, the ion trajectory axis of the FIB is set vertically above the sample surface, and the SEM electron gun and the 2 A foreign substance analyzer for an electronic device, comprising a secondary electron detector and an ordinal electron spectrometer.

15. The foreign object analyzer for an electronic device according to claim 11, wherein a Z-axis position sensor is provided on the sample stage.

16. The foreign matter analyzer for an electronic device according to claim 11. A foreign matter analyzer for an electronic device, comprising: a sample heating device provided at a port for introducing and unloading a sample into and from the analysis chamber, wherein the sample surface is heated and cleaned before the sample is introduced into the analysis chamber.

7. The foreign matter analyzer for an electronic device according to claim 11, further comprising a loading chamber connected to the processing chamber via a gate valve.

8. The foreign matter analyzer for an electronic device according to claim 11, further comprising a loading chamber connected to each of the processing chamber and the analysis chamber via a gate valve. Analysis equipment.

9. The foreign matter analyzer for an electronic device according to claim 11, wherein the degree of vacuum in the processing chamber is 1 E—4 Pa or more, and the degree of vacuum in the analysis chamber is 1 E—6 Pa or more. A foreign substance analyzer for an electronic device, comprising: a loading chamber connected to each of the processing chamber and the analysis chamber via a gate valve.

0. The foreign matter analyzer for an electronic device according to claim 11, further comprising a processing chamber, a loading chamber connected to each of the analysis chambers via a gate valve, and a gas being supplied to the processing chamber. A foreign substance analyzer for an electronic device, which is provided with an introduction mechanism.

1. The foreign matter analyzer for an electronic device according to claim 11, wherein the holder on which the object to be processed and analyzed is placed is moved from the stage together with the opening chamber connected to the processing chamber via a gate valve. A foreign substance analyzer for an electronic device, which is provided with a retract / return mechanism.

2. In the foreign matter analyzer for an electronic device according to claim 11, Along with an opening chamber connected to the above processing chamber via a gate valve, a mechanism shall be provided to evacuate the holder holding the object to be analyzed from the stage upward and return to the same position. Features Foreign substance analyzer for electronic devices.

23. The foreign matter analyzer for an electronic device according to claim 11, wherein the loading chamber connected to the processing chamber via a gate valve and the holder on which the processing target is placed are evacuated from the stage. . A foreign substance analyzer for an electronic device, comprising: a return mechanism; and a gas introduction mechanism in the processing chamber.

24. In the foreign matter analyzer for an electronic device according to claim 11, two or more gas introduction pipes for returning from vacuum to atmospheric pressure are connected to a port for introducing / unloading the sample into / from the analysis chamber. A foreign substance analyzer for an electronic device, comprising:

25. For a beam source whose vacuum pump is directly connected to the electron gun or ion source, the vacuum pump is supported by a support structure separate from the beam source column, and the beam source column and the air supply port of the vacuum pump are supported. And a foreign matter analyzing device for an electronic device, wherein the foreign matter analyzing device is connected with a plastic member.

26. Exposing the material surface of the foreign matter, analyzing the element contained in the exposed surface and the cross section around the foreign matter, analyzing the arrangement of elements and the thickness of film formation, and comparing it with the device design and manufacturing information. A foreign particle analyzer for an electronic device used in a method of manufacturing an electronic device for manufacturing an electronic device by specifying a device for generating a foreign particle and taking measures against the device, comprising a focused ion beam device and Auger electron spectroscopy. Including both analyzers, the equipment is provided under the same vacuum condition that is isolated from the atmosphere, a device that exposes a cross section containing foreign matter is a focused ion beam device, and a device that is used for the cross-sectional analysis is an OJE. The optical axis of the ion beam and electron beam is A foreign substance analyzer for an electronic device, wherein the foreign substance analyzer is close to a distance of 1 A or more and 20 μm or less on a vice surface.

7. The foreign matter analyzer for an electronic device according to claim 26, wherein the surface of the sample device having a diameter of 6 cm or more, on which the orifice electron spectrometer, the focused ion beam, and the device are mounted as they are, is brought into contact with the atmosphere. A foreign substance analyzer for electronic devices, wherein the apparatus is housed in a vacuum vessel having no common partition.

8. The foreign matter analyzer for an electronic device according to claim 26, wherein the FIB ion orbit axis is inclined at an angle of 30 ° or more and 90 ° or less with respect to a vertical upper direction of the analysis sample with respect to a digging surface. A foreign substance analyzer for an electronic device, wherein an orbit axis of an electron beam of an Auger electron spectrometer is matched so that an inclination with respect to a normal line is 5 ° or less.

9. The foreign matter analyzer for an electronic device according to claim 26, wherein a shield plate is temporarily disposed in front of an opening for drawing in an electron of a CMA during excavation of the sample surface by the FIB. A foreign substance analyzer for electronic devices, characterized in that:

27. The foreign matter analyzer for an electronic device according to claim 26, wherein a projection angle between the optical axis of the FIB ion source and the optical axis of the AES electron beam on the sample surface is 90 ° or more. A foreign matter analyzer for an electronic device, wherein the foreign matter is within a range of 80 ° or less.

1. The foreign matter analyzer for an electronic device according to claim 27, wherein the sample stage is rotated in a normal direction.

2. The foreign matter analyzer for an electronic device according to claim 31, wherein after the sample stage is rotated, the amount of movement in the XY-axis direction is calculated, and the foreign matter is automatically included in a screen for external appearance observation. Electronic device characterized by the following: Foreign matter separating device.

33. The foreign matter analyzer for an electronic device according to claim 26, wherein two ports for introducing and carrying out the sample into and out of the analysis chamber are provided. .

34. The foreign matter analyzer for an electronic device according to claim 26, wherein two or more samples can be loaded into a port for introducing and unloading the sample into and from the analysis chamber. .

3 5. Exposing the material surface of the foreign matter, analyzing the element contained in the exposed surface and the cross section around the foreign matter, analyzing the arrangement of elements and the thickness of film formation, and comparing it with the device design and manufacturing information. This is a method of manufacturing an electronic device that manufactures an electronic device by identifying the device that generates the foreign material and taking measures against the device, which is used in the position information of the foreign material, the 3D device structure of the product, and the manufacturing process. The information stored in the storage device, which stores information on the materials, film thicknesses, and manufacturing histories of individual products, is used to analyze the causes, processes, and equipment of foreign substances, and mediates storage media from devices that support analysis. A method for manufacturing an electronic device, which is obtained without being used.

36. Exposing the material surface of the foreign matter, analyzing the elements included in the exposed surface and the cross section around the foreign matter, analyzing the arrangement of elements and the thickness of film formation, and comparing it with the device design and manufacturing information. An electronic device manufacturing method for manufacturing an electronic device by specifying an apparatus for generating foreign matter and taking measures against the apparatus, wherein a device structure and / or a material in the vicinity of the foreign matter and / or one of the actual measurements is measured. A method of manufacturing an electronic device, comprising software for automatically detecting a difference between a result and corresponding design information of a product or assisting an operator in detecting the difference.

3 7. Exposing the material surface of the foreign matter, analyzing the element contained in the exposed surface and the cross section around the foreign matter, analyzing the arrangement of elements and the thickness of film formation, and setting the device. A method for manufacturing an electronic device in which a foreign matter generating device is identified by comparing the total with manufacturing information, and a measure is taken for the device to manufacture the electronic device. '' Manufacturing electronic devices characterized by including or supporting software for analyzing the thickness and material of the film in the depth direction at and near the position of the foreign matter based on the process information or any one of them. Method.

3 8. Exposing the material surface of the foreign matter, analyzing the element contained in the exposed surface and the cross section around the foreign matter, analyzing the arrangement of elements and the thickness of film formation, and comparing it with the device design and manufacturing information. An electronic device manufacturing method for manufacturing an electronic device by identifying a device for generating foreign matter and taking measures against the device, the information and process relating to the material and thickness of each element at arbitrary coordinates of the device. Manufacturing of electronic devices characterized by analyzing film thickness and thickness in the depth direction at and near the foreign matter based on process information or any of them, or including software supporting the analysis Method.

3 9. Exposing the material surface of the foreign matter, analyzing the element contained in the exposed surface and the cross section around the foreign matter, analyzing the arrangement of elements and the thickness of film formation, and comparing it with the device design and manufacturing information. A method for manufacturing an electronic device in which a device for generating foreign matter is specified, and a countermeasure is taken for the device to manufacture an electronic device. In order to analyze a film formation structure in foreign matter coordinates, an element layer at a foreign matter coordinate position is analyzed. Based on the information on the foreign matter, the elements at and near the foreign matter are extracted, and the information on the material and thickness of the film at the foreign matter position is obtained by combining the information on the film forming material and the thickness given for each element. Characteristic electronic device manufacturing method

40. Exposing the material surface of the foreign matter, analyzing the elements included in the exposed surface and the cross section around the foreign matter, and arranging the elements. The manufacturing method of an electronic device that manufactures an electronic device by identifying the device that generates the foreign material by comparing it with the manufacturing information, taking measures against the device, and the thickness of the material used in the manufacturing process. A method for manufacturing an electronic device, characterized in that a design value or a virtual value is given for all of the above, and the virtual film structure is referred to when specifying the cause of the foreign matter generation, the process, and the apparatus. 1. Exposing the material surface of the foreign matter, analyzing the element contained in the exposed surface and the cross section around the foreign matter, analyzing the arrangement of elements and the thickness of film formation, and comparing it with the device design and manufacturing information. This is a method of manufacturing an electronic device that manufactures an electronic device by identifying the device that generates foreign matter and taking measures against the device, including materials that do not originally remain on the product, such as etching processes, cleaning processes, and resists. Design values or virtual values are given for all the thicknesses of the materials used in the manufacturing process, and this virtual film structure is imaged and referenced when specifying the cause of foreign matter generation, process, and equipment. Manufacturing method of electronic device.