JP2006051555A - Nanometer-level structure composition observing method, manufacturing method of multi-layer film structure having interposed insulating layer, and nanometer-level structure composition observing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a nanometer-level structure composition observing method, a manufacturing method of a multi-layer film structure having an interposed insulating layer, and a nanometer-level structure composition observing device, analyzing the microstructure composition in a wide range of a sample having the multi-layer thin film structure having an interposed insulating layer with high accuracy. <P>SOLUTION: A plurality of projected structures 2 formed of the multi-layer film structure having the interposed insulating layer 3 are provided, and only in the projected structure 2 as an observation object, the upper and lower conductive parts 4, 5 are sequentially electrically short-circuited to perform observation. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a nano-level structural composition observation method, a manufacturing method of a multilayer film structure in which an insulating layer is interposed, and a nano-level structural composition observation apparatus, and in particular, a surface layer having a multilayer thin film structure in which an insulating layer is interposed. A characteristic nano-level structure composition observation method for accurately observing the interface structure of a wide area by an atom probe method, a method for manufacturing a multilayer film structure in which an insulating layer is interposed, and a nano-level structure composition observation apparatus It is.

In recent years, HDDs (hard disk drives) are rapidly becoming smaller and larger in capacity, and there is a need to develop heads and media for realizing high-density magnetic recording. From recording bits finely arranged on a medium In order to convert the generated magnetic signal into an electric signal with high efficiency by the reproducing head, it is required to make the MR head finer and thinner.

In such a miniaturized / thinned MR head, it is necessary to accurately form the thickness of each layer constituting the spin valve film and to maintain a good interface state between the layers.
For example, if the film thickness distribution is not uniform, the interface is curved, or if the constituent atoms are interdiffused at the interface and the interface is unclear, desired characteristics cannot be obtained.

  Therefore, in the past, the 2θ method using X-ray reflection at the interface was used to evaluate the film thickness and interface state of each layer such as the spin valve film and feed back the results to the manufacturing process. Improvement and production yield were improved.

  However, since the 2θ method is a method that uses the reflection intensity of X-rays at the interface, when the constituent atoms are interdiffused at the interface and the interface is unclear, a highly accurate analysis is difficult. In addition, even when an unexpected layer is present, it is difficult to perform highly accurate analysis.

  On the other hand, as a technique for solving such a problem, a three-dimensional atom probe method is known as a technique for directly observing a three-dimensional structure at an atomic level, and this atom probe method is 1 μm or less formed in a needle shape at an acute angle. The needle-like sample is irradiated with a pulsed high electric field or laser, and with this energy, atoms or clusters on the surface are electrolytically evaporated, and the three-dimensional atomic level structure of the sample is observed by a two-dimensional position detector.

  However, this atom probe method has a problem that only three-dimensional atomic level information of one needle point can be obtained, and two-dimensional information in a wide range such as a film thickness distribution cannot be obtained at a time.

  Therefore, the present inventors formed a plurality of needle-like structures on the substrate, and brought the extraction electrode close to each needle-like structure, thereby obtaining information on the three-dimensional atomic level of each needle-like structure. It has been proposed to analyze the three-dimensional structural composition in a wide range such as the film thickness distribution by acquiring and integrating all the information (see, for example, Patent Document 1), so refer to FIG. I will explain.

See FIG.
FIG. 8 is a conceptual configuration diagram of a three-dimensional structural composition measuring apparatus. After cutting the silicon substrate 61 into which B is locally ion-implanted so that a cross section perpendicular to the main surface appears, the cut surface is polished, Next, a plurality of needle-like structures 63 are formed on the surface of the polishing surface, and the extraction electrode 64 is brought close to the needle-like structures 63 to be evaporated by an electric field, and then extracted with an electric field applied with ionized constituent atoms or clusters. It is detected by the sensitive detector 65.

By measuring one needle-like structure 63, first, two-dimensional information is obtained, and three-dimensional structural composition information can be obtained by overlapping them in terms of time.
By performing this measurement for all the needle-like structures 63 and integrating all the obtained information, the B concentration distribution in the ion implantation region 62 can be obtained.

  By applying such a three-dimensional atom probe method to various samples, it is possible to evaluate adsorption, surface reaction, interface structure of multilayer film on a wide area of the substrate, or nano order such as point defects of materials. Defects, etc. can be detected, and the film thickness distribution and interface state of each layer in an MR head composed of a CPP (Current Perpendicular to the Plane) type GMR element can be evaluated.

  However, since this atom probe method involves an ionization process, electrons remain on the substrate side as a result of ionization. However, when an insulating layer is present, there is no escape field for electrons and measurement is continued by charge-up. There is a problem that can not be.

For example, there is a problem that it cannot be applied to the analysis of an MR head made of a CIP (Current In the Plane) type GMR element provided with upper and lower lead gap layers made of an Al ₂ O ₃ film or the like.

  Further, in the case of a GMR element having a CPP structure, in the case of an MTJ (ferromagnetic tunnel junction) type GMR element in which a tunnel insulating film is interposed in the middle, the analysis is similarly difficult. This is a common problem not only for GMR elements but also for various samples including an insulating film in the layer structure.

  On the other hand, in the atom probe method, a conductive film straddling the insulating layer is formed using a focused ion beam (FIB) method in order to prevent charge-up when the insulating layer is present in the sample to be analyzed. It has also been proposed to short-circuit the top and bottom (see, for example, Patent Document 2).

Therefore, by combining such a short circuit method using the FIB method and the above-described method of forming a plurality of needle-like structures, it is possible to analyze a multilayer thin film sample in which an insulating layer is interposed between CIP type GMR elements and the like. become.
JP 2004-117287 A JP 2001-208659 A

  However, even when the above-mentioned Patent Document 1 and Patent Document 2 are combined, there is a problem that detailed analysis with high density in the sample plane is difficult.

  That is, as apparent from the above-mentioned Patent Document 1, since the diameter of the opening at the lower end of the extraction electrode is about 50 nm, when the needle-like structure is formed at a pitch of 50 nm or less, a plurality of the extraction electrodes are formed with respect to the extraction electrode. These needle-like structures face each other, and it becomes difficult to determine which needle-like structure the detected particles have come from.

  On the other hand, in order to increase the accuracy of the determination, the needle-like structure may be formed with a pitch of 50 nm or more, but there is a problem that the observation point becomes sparse and the two-dimensional analysis with high accuracy cannot be performed.

  Further, assuming that the diameter of the opening at the lower end of the extraction electrode can be reduced to 20 nm or less, then the alignment between the needle-like structure to be measured and the extraction electrode becomes very difficult. There is a problem of becoming.

  Therefore, an object of the present invention is to analyze the fine structure composition in a wide range of a sample having a multilayer thin film structure in which an insulating layer is interposed with high accuracy.

FIG. 1 is a diagram illustrating the basic configuration of the present invention. Means for solving the problems in the present invention will be described with reference to FIG.
See FIG. 1 In order to solve the above problem, the present invention is based on the surface of the convex structure 2 of the sample 1 to be analyzed having the convex structure 2 having a multilayer structure with the insulating layer 3 interposed on the surface side. The nano-level structural composition of the convex structure 2 is observed by detaching particles 9 made of either atoms or clusters constituting the convex structure 2 one by one to the external space by external energy or internal energy 8. In the nano-level structural composition observation method, observation is performed by providing a plurality of convex structures 2 and electrically short-circuiting the upper and lower conductive portions 4 and 5 of only the convex structure 2 to be observed sequentially. Features.

  In this way, observation is performed by sequentially short-circuiting the upper and lower conductive portions 4 and 5 of only the convex structure 2 to be observed one by one, and the convex structure 2 that has been observed is electrically When the convex structure 2 is provided at a high density, the particles 9 fly only from the convex structure 2 in which the upper and lower conductive portions 4 and 5 are short-circuited. Therefore, highly accurate measurement is possible.

  Moreover, the convex structure 2 can be made dense by short-circuiting and opening the upper and lower conductive portions 4 and 5 of the convex structure 2 by using the focused ion beam 6 method that allows easy processing of a fine region. Even when it is provided, it is possible to selectively deposit or etch only one convex structure portion to be short-circuited or opened.

  Further, when the extraction electrode is used, the particles 9 come in even if the opening at the lower end of the extraction electrode is wide because the upper and lower conductive portions 4 and 5 of the convex structure 2 are short-circuited. Therefore, it is possible to perform measurement with high accuracy, and conversely, the wide opening portion facilitates alignment with the convex structure 2 to be observed.

  In this case, the internal energy 8 is typically a field evaporation due to a pulsed high electric field, and the external energy is typically a pulsed electromagnetic wave such as a pulsed laser beam.

  Further, as an apparatus configuration, in addition to the normal atom probe apparatus configuration, a raw material gas for depositing a conductive film 7 for sequentially electrically short-circuiting the upper and lower conductive portions 4 and 5 of the convex structure 2 is used. Introducing means and a focused ion beam irradiation means for irradiating the focused ion beam 6 when depositing and removing the conductive film 7 are provided.

  As described above, a normal apparatus configuration includes only a raw material gas introduction means and a focused ion beam irradiation means, and the sample 1 to be analyzed is not taken out of the vacuum system, or a separate film forming apparatus and etching apparatus are attached. Therefore, it is possible to sequentially observe the convex structures 2 one by one successively, without simplifying the structure, so that the apparatus configuration is simplified, the observation time is shortened, and the surface of the convex structure portion is exposed to the outside air. Will not be contaminated.

In addition, the production yield of the product can be increased by advancing the manufacturing process or feeding back to the manufacturing process according to the result of observing the nano-level structural composition of the multilayer structure with the insulating layer 3 interposed by the nano-level structural composition observation method. It is possible to improve the performance of the product.
In particular, this is effective for a magnetoresistive element constituting a reproducing head whose interface state greatly affects the characteristics.

  In the present invention, it is possible to analyze with high accuracy a convex structure formed with a high density three-dimensional structure over a wide range of a multilayer thin film structure in which an insulating layer is interposed.

  In the present invention, a plurality of convex structure portions are formed on the surface of a sample to be analyzed having a convex structure having a multilayer structure with an insulating layer interposed on the surface side, and only one convex structure to be observed is provided. A conductive film is deposited on the upper and lower conductive portions using an FIB method to electrically short-circuit, and a pulse high voltage or pulse laser light for detachment is applied to the convex structure portion to form a convex structure. After observing the nano-level structural composition of the convex structure by leaving particles consisting of either atoms or clusters one by one into the external space, the FIB method is applied to the convex structure that has been observed. Using the FIB method to deposit the conductive film using the FIB method to observe the upper and lower conductive portions of only one convex structure to be observed next, and removing the conductive film. To the number of convex structures that require this process It shall be made by.

Here, with reference to FIG. 2 thru | or FIG. 7, the nano level structure composition observation method of Example 1 of this invention is demonstrated.
See Figure 2
First, the base of the slider is provided with Al ₂ O ₃ -TiC lower magnetic shield layer 12 made of NiFe or the like via an Al ₂ O ₃ film on the substrate 11 (not shown), on which, Al ₂ O _{After the} lower lead gap layer 13 made of 3 is provided, the spin valve film 14 is formed by sputtering.

  For example, the spin valve film 14 includes a 5 nm Ta underlayer 15, a 2 nm NiFe free layer 16, a 1.5 nm CoFeB free layer 17, a 2.8 nm Cu intermediate layer 18, a 2 nm CoFeB pinned layer 19, a 13 nm It consists of a PdPtMn antiferromagnetic layer 20 and a 6 nm Ta cap layer 21.

Next, by performing ion milling using the resist pattern 22 as a mask, the sense portion 23 is formed by processing into a predetermined shape, and subsequently, a magnetic domain control film 24 made of CoCrPt is formed by sputtering.
See Figure 3

  Next, after removing the resist pattern 22, an electrode terminal conductive film made of a 3 nm Cr film and a 30 nm Au film is formed, and an electrode terminal 25 is formed by ion milling using the new resist pattern as a mask. .

Next, after removing the resist pattern, an upper lead gap layer 26 made of Al ₂ O ₃ and an upper magnetic shield layer 27 made of NiFe are provided to complete the basic structure of the MR head.

Next, after cutting into rectangular chips 28 by dicing, each chip 28 penetrates the lower lead gap layer 13 and forms the lower magnetic shield layer 12 by FIB method using Ga ions 29. By forming the reaching needle-like structures 30 in a matrix, the nano-level structural composition observation sample 10 is completed.
In this case, the pitch of the needle-like structures 30 is, for example, 150 nm, the diameter of the handle portion of each needle-like structure 30 is 100 nm, and the diameter of the tip portion is 50 nm.

See Figure 5
Next, the nano-level structural composition observation sample 10 is fixed to a sample holder 42 provided in the nano-level structural composition observation apparatus 40.
The nano-level structural composition observation apparatus 40 includes a vacuum vessel 41, an extraction electrode 43, a position sensitive detector 44, an extraction power source 45, and a pulse high voltage power source 46, and a FIB source 47 and a raw material unique to the present invention. A gas introduction pipe 48 is provided.
In this case, the extraction electrode 43 is formed of a W cone-shaped hollow cylindrical body having an opening with a diameter of 8 μm at the upper end and a diameter of 5 μm at the lower end. In addition, a hole having a diameter of 500 nm is provided at the center.

See FIG.
First, the W (CO) ₆ gas 49 is caused to flow from the source gas introduction pipe 48 into the vicinity of the needle-like structure 30 in the vacuum vessel 41 and the lower magnetism of a specific single needle-like structure 30 to be observed. By irradiating Ga ions 50 from the FIB source 47 toward the vicinity of the shield layer 13, the W film 51 is made to have a chemical vapor so as to short-circuit the lower magnetic shield layer 12 and the spin valve film 14 formed of the upper conductive multilayer thin film structure. Phase deposition.

  Next, the extraction electrode 43 is brought close to the tip of the needle-like structure 30 on which the W film 51 is formed, and the constituent at the tip is subjected to electric field evaporation by the pulsed high electric field from the pulse high voltage power source 46, and ionized The ionized particles are extracted by the extraction electrode 43, and the extracted particles 52 are accelerated by a DC voltage applied between the nano-level structural composition observation sample 10 and the position sensitive detector 44 and detected by the position sensitive detector 44. .

Next, again using the FIB method, the W film 51 is removed by sputter etching by irradiating the W film 51 from the FIB source 47 toward the W film 51, and the needle-like structure 30 whose observation has been completed. The lower magnetic shield layer 12 and the upper spin-valve film 14 having a conductive multilayer thin film structure are electrically opened.
In the figure, the needle-like structure 30 that has been observed is shown in the same size as before the observation, but actually, the electric field evaporates depending on the observation time and becomes smaller. Most of the structure 30 disappears.

See FIG.
Next, the W (CO) ₆ gas 49 is again flowed from the source gas introduction pipe 48 toward the vicinity of the needle-like structure 30, and the lower magnetic shield of a specific single needle-like structure 30 to be observed next. By irradiating Ga ions 50 from the FIB source 47 toward the vicinity of the layer 13, the W film 51 is formed in a chemical vapor phase so as to short-circuit the lower magnetic shield layer 12 and the spin valve film 14 formed of the upper conductive multilayer thin film structure. Evaporate.
Thereafter, the entire observation is completed by repeating the number of the needle-like structures 30 that require this chemical vapor deposition-observation-removal.

  For example, information regarding the nano-level three-dimensional composition structure with respect to the film thickness and the interface state is obtained at 50 points or more of the chip 28, and whether the film composition and the interface steepness are within the initial design values. If the value is within the design value, the product is allowed to flow. If the value is outside the design value, the processing conditions of the film forming step or the annealing step for imparting magnetization after the film forming are changed. Perform a NOGO test.

  As described above, according to the first embodiment of the present invention, by feeding back the observation result to the manufacturing process of the reproducing head, a high-performance reproducing head can be stably manufactured, and as a whole compared with the conventional one. It is possible to improve the yield, shorten the throughput, and reduce the manufacturing unit price.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the conditions and configurations described in the embodiments, and various modifications are possible. For example, the multilayer thin film structure described in each embodiment Is merely an example, and is appropriately changed according to the multilayer thin film structure of the device to be analyzed.

In the above embodiment, the conductive film to be short-circuited is the W film. However, the conductive film is not limited to the W film, and a C (carbon) film that can be formed by the FIB method is used similarly to the W film. If a C film is used, Ga ions may be irradiated in a state where a hydrocarbon gas such as C ₁₄ H ₁₀ is flowed.

  In the above embodiment, only a voltage is applied at the time of field evaporation and ionization, but a pulsed electromagnetic wave such as a laser beam may be applied in synchronization with the pulse voltage. Field evaporation at the tip can be easily caused, and is particularly effective when the size of the tip is large.

  Furthermore, evaporation and ionization may be performed only with pulsed electromagnetic waves such as laser light without applying an electric field.

  In the above embodiment, the conductive film that short-circuits the upper and lower conductive regions is removed and opened by FIB after the observation is completed. However, the entire convex structure is evaporated due to the observation. Therefore, it is not always necessary to remove the conductive film by FIB after the observation is completed.

The detailed features of the present invention will be described again with reference to FIG. 1 again.
Again see Figure 1
(Additional remark 1) From the surface of the said convex structure 2 of the sample 1 to be analyzed which has the convex structure 2 which consists of a multilayer film structure in which the insulating layer 3 interposes on the surface side, the said convex shape by external energy or internal energy 8 In the nano-level structural composition observation method for observing the nano-level structural composition of the convex structure 2 by detaching particles 9 consisting of either atoms or clusters constituting the structure 2 one by one to the external space, A nano-level structural composition characterized in that a plurality of convex structures 2 are provided, and observation is performed by sequentially electrically shorting the upper and lower conductive portions 4 and 5 of only the convex structures 2 to be observed. Observation method.
(Supplementary Note 2) The upper and lower conductive portions 4 and 5 of the convex structure 2 are short-circuited by deposition of the conductive film 7 using the focused ion beam 6 method, and after the observation is finished, the convex structure 2 2. The nano-level structure composition according to claim 1, wherein the conductive film 7 in which the upper and lower conductive parts 4 and 5 are short-circuited is irradiated with a focused ion beam 6 to remove the conductive film 7. Observation method.
(Supplementary Note 3) The extraction electrode is brought close to the convex structure 2 to be observed and the particles 9 detached from the surface of the convex structure 2 are extracted through an opening provided in the extraction electrode. The nano-level structural composition observation method according to Supplementary Note 1 or 2,
(Supplementary note 4) The nano-level structure composition observation method according to any one of supplementary notes 1 to 3, wherein the internal energy 8 is applied as a pulsed high electric field.
(Supplementary note 5) The nano-level structure composition observation method according to any one of supplementary notes 1 to 3, wherein the application of the external energy is a pulsed electromagnetic wave.
(Additional remark 6) From the surface of the convex structure 2 of the sample 1 to be analyzed which has the convex structure 2 which consists of the multilayered film structure which the insulating layer 3 interposes on the surface side, the said convex structure by external energy or internal energy 8 In the nano-level structural composition observation apparatus for observing the nano-level structural composition of the convex structure 2 by detaching particles 9 consisting of either atoms or clusters constituting the structure 2 one by one to the external space, Source gas introduction means for depositing a conductive film 7 for electrically short-circuiting the upper and lower conductive portions 4 and 5 of the convex structure 2 in sequence, and focused ions when depositing and removing the conductive film 7 A nano-level comprising at least a focused ion beam irradiating means for irradiating the beam 6 and an extraction electrode for extracting the particles 9 separated from the surface of the convex structure 2. Le structure composition observation device.
(Supplementary note 7) After observing the nanolevel structure composition of the multilayer structure in which the insulating layer 3 is interposed by the nanolevel structural composition observation method according to any one of supplementary notes 1 to 5, the observation result is within a design allowable range. A method of manufacturing a multilayer structure with an insulating layer 3 interposed, wherein the progress of the manufacturing process is determined depending on whether or not it is inside.
(Appendix 8) An acceptable range determined by observation results after observing the nanolevel structure composition of the multilayer film structure in which the insulating layer 3 is interposed by the nanolevel structure composition observation method according to any one of appendices 1 to 5. The manufacturing method of the multilayer film structure in which the insulating layer 3 is interposed is characterized by feeding back and reflecting the preferable manufacturing conditions in the manufacturing process of the multilayer film structure in which the insulating layer 3 is interposed.
(Additional remark 9) The multilayer film structure in which the said insulating layer 3 interposes is a magnetoresistive element which comprises a read-head, The multilayer film structure in which the insulating layer 3 in any one of Additional remark 7 or 8 is interposed Production method.

  As a practical example of the present invention, a GMR element constituting a read head is typical, but the read head is not limited, and the composition structure and interface state in the vicinity of the interface of the gate insulating film in the MISFET are problematic. The present invention is also applied to a method for analyzing a nano-level structure composition of a semiconductor element, and is applied to an analysis of a multilayer structure film in which at least an insulating layer is interposed.

It is explanatory drawing of the fundamental structure of this invention. It is explanatory drawing of the process to the middle of the nano level structure composition observation method of Example 1 of this invention. It is explanatory drawing of the process to the middle after FIG. 2 of the nano level structure composition observation method of Example 1 of this invention. It is explanatory drawing of the process to the middle after FIG. 3 of the nano level structure composition observation method of Example 1 of this invention. It is explanatory drawing of the process to the middle after FIG. 4 of the nano level structure composition observation method of Example 1 of this invention. It is explanatory drawing of the process to the middle after FIG. 5 of the nano level structure composition observation method of Example 1 of this invention. It is explanatory drawing of the process after FIG. 6 of the nano level structure composition observation method of Example 1 of this invention. It is a notional block diagram of a three-dimensional structural composition measuring apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Analyzed sample 2 Convex structure 3 Insulating layer 4 Conductive part 5 Conductive part 6 Focused ion beam 7 Conductive film 8 Internal energy 9 Particle 10 Nano-level structural composition observation sample 11 Al ₂ O ₃ —TiC substrate 12 Lower magnetic shield layer 13 Lower read gap layer 14 Spin valve film 15 Ta underlayer 16 NiFe free layer 17 CoFeB free layer 18 Cu intermediate layer 19 CoFeB pinned layer 20 PdPtMn antiferromagnetic layer 21 Ta cap layer 22 Resist pattern 23 Sense part 24 Magnetic domain control film 25 Electrode terminal 26 Upper lead gap layer 27 Upper magnetic shield layer 28 Chip 29 Ga ion 30 Needle-like structure 40 Nano-level structural composition observation device 41 Vacuum vessel 42 Sample holder 43 Extraction electrode 44 Position sensitive detector 45 Extraction power supply 46 pulse high voltage power supply 47 FIB source 48 original Gas introducing pipe 49 W (CO) ₆ gas 50 Ga ions 51 W film 52 particles 61 silicon substrate 62 an ion implantation region 63 needle-like structure 64 extraction electrode 65 position sensitive detector

Claims (5)

From the surface of the convex structure of the sample to be analyzed having a convex structure consisting of a multilayer structure with an insulating layer interposed on the surface side, atoms or clusters constituting the convex structure by external energy or internal energy In the nano-level structural composition observation method for observing the nano-level structural composition of the convex structure by detaching any one particle from the exterior space one by one, a plurality of the convex structures are provided, A method for observing a nano-level structural composition, characterized in that observation is performed by sequentially short-circuiting the upper and lower conductive portions of only the convex structure. The upper and lower conductive portions of the convex structure are short-circuited by depositing a conductive film using a focused ion beam method, and the upper and lower conductive portions of the convex structure are short-circuited after the observation is completed. 2. The nano-level structural composition observation method according to claim 1, wherein the conductive film is irradiated with a focused ion beam to remove the conductive film. 3. The particle separated from the surface of the convex structure by bringing the extraction electrode close to the convex structure to be observed is extracted through an opening provided in the extraction electrode. The nano-level structural composition observation method according to 1. From the surface of the convex structure of the sample to be analyzed having a convex structure consisting of a multilayer structure with an insulating layer on the surface side, either atoms or clusters constituting the convex structure by external energy or internal energy In the nano-level structural composition observation apparatus for observing the nano-level structural composition of the convex structure by detaching the particles made of the particles one by one to the external space, the upper and lower conductive portions of the convex structure are sequentially Source gas introduction means for depositing a conductive film to be electrically short-circuited, focused ion beam irradiation means for irradiating a focused ion beam when depositing and removing the conductive film, and the convex structure A nano-level structural composition observation apparatus comprising at least an extraction electrode for extracting particles detached from the surface of an object. After observing the nano-level structure composition of the multilayer film structure in which the insulating layer is interposed by the nano-level structure composition observation method according to any one of claims 1 to 3, the observation result is within a design allowable value range. A method of manufacturing a multilayer structure with an insulating layer interposed, wherein the progress of the manufacturing process is determined depending on whether or not the process proceeds.

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