A failure analysis method for organic solderability film

Abstract

The present application provides a failure analysis method for an organic solder paste film, which relates to the field of printed circuit technology, and includes obtaining a sample with an organic solder paste film provided on its surface; marking a closed area on the surface of the sample as a surface observation area, and depositing a metal protective layer on an area outside the surface observation area on the sample; cutting the area with the metal protective layer on the sample along any direction to form a first cross-sectional observation area; detecting the surface observation area and the first cross-sectional observation area; performing an aging test on the sample, and observing whether the surface of the body is oxidized at preset intervals; detecting the surface observation area; forming a second cross-sectional observation area on the sample and detecting it; repeating the above steps to detect the surface observation area; obtaining and detecting the Nth cross-sectional observation area; recording the current status data of the sample when the body is exposed or the organic solder paste film is completely consumed; and detecting the quality of the organic solder paste film based on the comparison between the current status data of the organic solder paste film and a preset threshold value.

Description

Technical Field

[0001] The present application relates to the field of printed circuit technology, and in particular to a failure analysis method for an organic solderability film. Background Art

[0002] Organic solderability preservatives (OSPs) are a surface treatment process for copper foil on printed circuit boards (PCBs) that complies with directive requirements. They are short for Organic Solderability Preservatives (OSPs), also known as copper protectants. Simply put, an organic film is chemically grown on a clean, bare copper surface. This film offers resistance to oxidation, heat shock, and moisture, protecting the copper surface from further rust (oxidation or sulfide) in normal environments. However, during the subsequent high temperatures of soldering, this protective film must be easily removed by flux, allowing the exposed, clean copper surface to bond with the molten solder in a very short time, forming a strong solder joint.

[0003] Therefore, whether the organic solder paste film fails directly affects the performance of the copper surface. It is necessary to accurately grasp the failure of the organic solder paste film. The existing technology for failure analysis of the organic solder paste film is still inaccurate, which affects the effective use of the organic solder paste film. Summary of the Invention

[0004] The purpose of the embodiments of the present application is to provide a failure analysis method for an organic solderability film, which can accurately perform failure analysis on the organic solderability film, thereby evaluating the quality of the organic solderability film.

[0005] In one aspect of an embodiment of the present application, a failure analysis method for an organic solderability film is provided, comprising obtaining a sample having an organic solderability film provided on its surface; wherein the organic solderability film is provided on the body of the sample; marking a closed area on the surface of the sample as a surface observation area, and depositing a metal protective layer in an area outside the surface observation area on the sample; cutting the area having the metal protective layer on the sample in any direction to form a first cross-sectional observation area; detecting the surface observation area to obtain the surface morphology of the organic solderability film; detecting a plurality of observation points in the first cross-sectional observation area respectively, obtaining the surface morphology of the body of the sample and the organic solderability film, and the thickness of the organic solderability film respectively, to obtain initial state data of the surface observation area, and taking the average value of the data of the plurality of observation points in the first cross-sectional observation area as the initial state data of the first cross-sectional observation area; performing an aging test on the sample, and observing whether the surface of the body is oxidized at preset intervals; detecting the surface observation area to obtain the surface morphology of the organic solderability film; cutting the area having the metal protective layer on the sample in any direction to form a second cross-sectional observation area; respectively Detect multiple observation points in the second cross-sectional observation area, respectively obtain the surface morphology of the sample body and the organic solderability film, as well as the thickness of the organic solderability film, to obtain the initial state data of the surface observation area, and the data average value of the multiple observation points in the second cross-sectional observation area is used as the initial state data of the second cross-sectional observation area; perform an aging test on the sample, and observe whether the surface of the body is oxidized at preset intervals; detect the surface observation area, and obtain the surface morphology of the organic solderability film; cut the area with a metal protective layer on the sample in any direction to form an N-th cross-sectional observation area; detect multiple observation points in the N-th cross-sectional observation area, respectively obtain the surface morphology of the sample body and the organic solderability film, as well as the thickness of the organic solderability film, to obtain the initial state data of the surface observation area, and the data average value of the multiple observation points in the N-th cross-sectional observation area is used as the initial state data of the N-th cross-sectional observation area; N is a natural number; when the sample body is exposed or the organic solderability film is completely consumed, record the current state data of the sample; compare the current state data of the organic solderability film with the preset threshold value to detect the quality of the organic solderability film.

[0006] Optionally, obtaining the sample with an organic solderability protection film provided on the surface includes: cutting out a sample that meets size requirements on the pad; and cleaning the sample.

[0007] Optionally, after obtaining the sample with the organic solderability film provided on the surface, the method further includes: placing the sample on a sample stage; and connecting the sample stage and the sample via a conductive adhesive.

[0008] Optionally, marking a closed area on the sample surface as a surface observation area, and depositing a metal protective layer in the area outside the surface observation area on the sample includes: marking the surface observation area; and depositing a metal protective layer in the area outside the surface observation area on the sample by ion beam deposition.

[0009] Optionally, cutting the area having the metal protective layer on the sample in any direction to form a first cross-sectional observation area includes: using an ion beam probe to roughly cut the sample by focusing an ion beam to obtain the first cross-sectional observation area; and smoothing the first cross-sectional observation area.

[0010] Optionally, the surface observation area is detected to obtain the surface morphology of the organic solderability film; multiple observation points in the first cross-sectional observation area are detected respectively to obtain the surface morphology of the sample body and the organic solderability film, as well as the thickness of the organic solderability film, to obtain the initial state data of the surface observation area, and the data average value of the multiple observation points in the first cross-sectional observation area is used as the initial state data of the first cross-sectional observation area, including: aligning the electron beam probe with and magnifying the surface observation area to obtain the surface morphology of the organic solderability film; aligning the electron beam probe with and magnifying the first cross-sectional observation area to obtain the surface morphology of the sample body and the organic solderability film, as well as the thickness of the organic solderability film.

[0011] Optionally, an aging test is performed on the sample, and the surface of the body is observed to see if it is oxidized at preset intervals; the surface observation area is detected to obtain the surface morphology of the organic solderability film; the area with the metal protective layer on the sample is cut in any direction to form a second cross-sectional observation area; multiple observation points in the second cross-sectional observation area are detected respectively to obtain the surface morphology of the sample body and the organic solderability film, as well as the thickness of the organic solderability film, to obtain initial state data of the surface observation area, and the data average value of the multiple observation points in the second cross-sectional observation area is used as the initial state data of the second cross-sectional observation area, including: placing the sample in an aging box, and aging the sample according to a preset temperature and time; taking out the sample at preset intervals to observe whether the surface of the body is oxidized; observing the surface observation area of the sample to obtain the surface morphology of the sample body and the organic solderability film, as well as the thickness of the organic solderability film; cutting the sample to form a second cross-sectional observation area, and obtaining the surface morphology of the sample body and the organic solderability film, as well as the thickness of the organic solderability film by taking the average value of the initial state data of the multiple observation points in the second cross-sectional observation area; after the observation is completed, placing the sample in an aging box for further aging.

[0012] Optionally, placing the sample in an aging box and aging the sample according to a preset temperature and time includes aging the sample at a temperature of 100° C. to 200° C. and a cycle of 2 hours to 6 hours.

[0013] Optionally, after taking out the sample at a preset interval and observing whether the surface of the body is oxidized, the method further includes: performing surface micro-processing on the first cross-sectional observation area to obtain a first cross-sectional observation area that is not oxidized.

[0014] Optionally, the material of the body of the sample is copper, and the material of the metal protective layer is platinum.

[0015] The failure analysis method for an organic solderability film provided in the embodiments of this application examines samples of the organic solderability film from both the surface observation area and multiple cross-sectional observation areas. Using an aging sample approach, the quality of the OSP film is assessed based on storage time. The aging time discussed in this application precisely reflects the effects of acceleration time and analysis time on the OSP film. Furthermore, a focused ion beam (FIB) method is used for cutting, enabling precise positioning and cutting to prepare the sample's cross-sectional observation area. This area is then examined using a SEM, improving preparation and testing accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 This is one of the flow charts of the failure analysis method of the organic solderability film provided in this embodiment;

[0018] Figure 2 This is the second flow chart of the failure analysis method of the organic solderability film provided in this embodiment;

[0019] Figures 3 and 4 is a schematic diagram of the focused ion beam provided in this embodiment;

[0020] Figure 5 This is a schematic diagram of a scanning electron microscope;

[0021] Figures 6 to 9 These are images of the surface observation area and cross-sectional observation area formed in this embodiment. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application.

[0023] In the description of this application, it should be noted that the terms "inner" and "outer" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or the orientations or positional relationships in which the product of this application is typically placed when in use. These terms are intended solely to facilitate the description of this application and simplify the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" and the like are used solely for distinction and should not be construed as indicating or implying relative importance.

[0024] It should also be noted that, unless otherwise expressly specified or limited, the terms "disposed" and "connected" should be understood broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0025] Please refer to Figure 1 and Figure 2 As shown, the embodiment of the present application provides a failure analysis method for an organic solderability film, comprising:

[0026] S100: Obtain a sample with an organic solderability film provided on the surface.

[0027] An organic soldering film is provided on the surface of the sample body. The organic soldering film is also called copper protectant, or OSP. Therefore, the body of the sample is generally copper, and an organic soldering film is provided on the copper body.

[0028] Specifically, this application selects an OSP process pad (PCB) as a test object, cuts out samples that meet size requirements on the pad, and cleans the samples.

[0029] Because the PCB is too large to fit inside the electron microscope chamber for observation, use a sampler or large scissors to cut the PCB into a smaller piece, preferably within 20mm*20mm. Some PCB debris will remain during sampling. Clean the small piece with an ear bulb or air gun until there is no foreign matter on the sample surface.

[0030] S101: Place the sample on the sample stage.

[0031] S102: Connect the sample stage and the sample through conductive glue.

[0032] Specifically, the sample is placed in a dual-beam FIB (Helios G4 CX) instrument. Conductive adhesive is used to connect the sample stage to the edge of the sample to ensure charge neutralization and image stability. After vacuum is evacuated, the electron beam is turned on for observation, and the electron beam is moved to position the sample to locate the target pad within the ion beam.

[0033] S110: Mark a closed area on the sample surface as a surface observation area, and deposit a metal protective layer on the area outside the surface observation area of the sample.

[0034] Mark the surface observation area; and deposit a metal protective layer on the sample surface outside the observation area by ion beam deposition.

[0035] This application uses platinum (Pt) plating as an example. The ion beam is turned on, a surface observation area is selected, and deposition is performed under the ion beam. The GIS-Pt is inserted and Pt is deposited on all four sides of the surface observation area at 30kV and 0.43nA. After deposition is complete, the GIS-Pt is retracted. Specifically, a metal protective layer with parameters of 100μm × 1μm × 0.2μm can be deposited, and the length, width, and thickness of the metal protective layer can be adjusted.

[0036] Turn on the electron beam and select a position as the surface observation area of the first cross-section observation area. Because the surface will be damaged when the ion beam deposits Pt, it is first deposited under the electron beam and the GIS-Pt is inserted. Under the parameters of 5kV and 1.4-2.8nA, 15μm×3μm×0.5μm Pt is deposited (the length, width and thickness can be adjusted as needed) to protect the sample surface. After the deposition is completed, the GIS-Pt is retracted.

[0037] Since the Pt deposited by electron beam is relatively loose, it needs to be thickened by ion beam deposition. Turn on the ion beam and continue to use the ion beam to deposit 15μm×3μm×1μm Pt (the thickness can be adjusted as needed) on the Pt deposited by electron beam at the parameters of 30kV and 80pA. After the deposition is completed, the GIS-Pt is recovered.

[0038] S120: Cutting the area having the metal protective layer on the sample along any direction to form a first cross-sectional observation area.

[0039] This application adopts the method of focused ion beam cutting. Focused ion beam (abbreviation: FIB; full name: Focused Ion beam) ionizes liquid high-temperature gallium into Ga ions, which are then accelerated by an electric field and focused by an electrostatic lens to drive high-energy (high-speed) Ga ions to a designated location to strip atoms from the sample surface. The reaction products are vaporized and pumped away by a vacuum pump. At the same time, through the gas injection system (GIS), chemical gases can be physically sputtered to selectively strip or deposit certain materials to complete micro- and nano-scale surface morphology processing. FIB can obtain the most original morphology of the material. Its principle diagram is as follows: Figure 3 and Figure 4 As shown, Figure 3 The middle sample stage is tilted 52°, which allows the FIB to cut vertically downwards, and the subsequent SEM also has enough angle to observe the cross section.

[0040] The sample was roughly cut by focusing the ion beam to obtain the first cross-section observation area. Specifically, the ion beam probe was turned on, the sample was moved to the optimal working distance, the first cross-section observation area was facing the ion beam probe, and an area of 15 μm × 14 μm × 7 μm was cut at 30 kV and 9.3 nA (the width y and thickness z could be adjusted as needed).

[0041] The first cross-section observation area is smoothed and polished with 30kV and 2.5nA parameters at a size of 15μm×3μm×7μm (the width y can be adjusted as needed) on the basis of rough cutting until there is no obvious curtain effect.

[0042] S130: Detect the surface observation area to obtain the surface morphology of the organic solderability film; detect multiple observation points in the first cross-sectional observation area respectively to obtain the surface morphology of the sample body and the organic solderability film, as well as the thickness of the organic solderability film, to obtain initial state data of the surface observation area, and the average value of the data of the multiple observation points in the first cross-sectional observation area is used as the initial state data of the first cross-sectional observation area.

[0043] The surface observation area is aligned and magnified by the electron beam probe to obtain the surface morphology of the organic solderability film.

[0044] When the electron beam probe is used for observation, the detection principle of the scanning electron microscope (also known as scanning electron microscope) is used. Figure 5 As shown in Figure 1, a scanning electron microscope (SEM) is an observation method between a transmission electron microscope and an optical microscope. It uses a narrow, focused high-energy electron beam to scan a sample. The interaction between the beam and the material stimulates various physical information, which is then collected, amplified, and re-imaged to characterize the microscopic morphology of the material.

[0045] Specifically, turn on the electron beam probe, aim at the surface observation area, and observe the morphology of the OSP film surface by magnifying 1000X, 3000X, 5000X, and 10000X (the magnification can be adjusted as needed) from the center point.

[0046] Then, the electron beam probe is aligned and the first cross-section observation area is magnified to obtain the surface morphology of the sample body and the organic solderability film, as well as the thickness of the organic solderability film.

[0047] When moving to the first cross-sectional observation area, multiple observation points are determined on the first cross-sectional observation area for observation respectively to obtain the status data of the corresponding observation points. For example, 5 positions can be selected and magnified by 20000-50000X (the magnification can be adjusted as needed) to observe the morphology of the OSP film and the copper body, measure the thickness of the OSP film, and calculate the average value.

[0048] S140: Perform an aging test on the sample, and observe whether the surface of the body is oxidized at preset intervals; detect the surface observation area to obtain the surface morphology of the organic solderability film; cut the area with the metal protective layer on the sample along any direction to form a second cross-sectional observation area; detect multiple observation points in the second cross-sectional observation area respectively, and obtain the surface morphology of the sample body and the organic solderability film, as well as the thickness of the organic solderability film, to obtain initial state data of the surface observation area, and the average value of the data of the multiple observation points in the second cross-sectional observation area is used as the initial state data of the second cross-sectional observation area.

[0049] S141: First, place the sample in an aging box and age the sample according to the preset temperature and time; specifically, the sample can be aged at a temperature of 100°C to 200°C and a cycle of 2 hours to 6 hours. The specific aging parameters can be adjusted according to actual conditions.

[0050] S142: Observe whether the surface of the body is oxidized.

[0051] S143: The first cross-sectional observation area is then subjected to surface micro-processing to obtain an unoxidized first cross-sectional observation area. Because the FIB-cut cross section is affected by the environment, the cross-sectional observation area is finely polished using the FIB. Parameters are 30 kV and 2.5 nA, resulting in a cross-sectional observation area with dimensions of 15 μm × 0.2 μm × 7 μm. The width y can be adjusted as needed to obtain an unoxidized first cross-sectional observation area.

[0052] S144: taking out the sample at a preset interval and observing the surface observation area of the sample to obtain the surface morphology of the sample body and the organic solderability film, as well as the thickness of the organic solderability film.

[0053] S145: Cut the sample to form a second cross-sectional observation area, and obtain the surface morphology of the sample body and the organic solderability film, as well as the thickness of the organic solderability film, by averaging the initial state data of multiple observation points in the second cross-sectional observation area.

[0054] S146: After the observation is completed, the sample is transferred to the aging box for further aging.

[0055] S150: Perform an aging test on the sample and check whether the surface of the body is oxidized at preset intervals; detect the surface observation area to obtain the surface morphology of the organic solderability protection film; cut the area with the metal protective layer on the sample along any direction to form the Nth cross-sectional observation area; detect multiple observation points in the Nth cross-sectional observation area respectively, and obtain the surface morphology of the sample body and the organic solderability protection film, as well as the thickness of the organic solderability protection film, to obtain the initial state data of the surface observation area, and the average value of the data of the multiple observation points in the Nth cross-sectional observation area is used as the initial state data of the Nth cross-sectional observation area; N is a natural number.

[0056] It can be seen that for the surface observation area, the steps of detection-aging-detection-aging are repeated, and the detection is performed in situ. That is to say, once the surface observation area is determined, subsequent multiple detections are all performed in the same surface observation area.

[0057] As for the cross-sectional observation area, there are multiple cross-sectional observation areas. Repeated cutting forms the first cross-sectional observation area - detect the first cross-sectional observation area - aging - cutting forms the second cross-sectional observation area - detect the second cross-sectional observation area - aging -... cutting forms the Nth cross-sectional observation area - detect the Nth cross-sectional observation area - aging. In other words, for the cross-sectional observation area, each time after aging, it needs to be re-cut to form a new cross-sectional observation area. Each detection is to detect the corresponding new cross-sectional observation area, and each cross-sectional observation area takes multiple observation points for separate detection, and the average value is taken as the data of this cross-sectional observation area.

[0058] Take out samples for testing at preset intervals and record the test data for each time, including the data of the surface observation area and the cross-sectional observation area each time. For each cross-sectional observation area, after each aging, it is necessary to perform surface micro-processing on the new cross-sectional observation area after cutting and then perform data testing. Repeat the above steps until the surface of the OSP film or the copper body changes significantly, that is, the sample is exposed to the body.

[0059] During the inspection, it is also necessary to check whether the surface of the body is oxidized.

[0060] S160: When the sample body is exposed or the organic solderability film is completely consumed, the current status data of the sample is recorded.

[0061] After continuous aging tests, the organic solderability film will gradually be consumed to expose the copper body. When the body is exposed, the organic solderability film has not been completely consumed, and may only be consumed in a certain area of the body, so that the body in this area is exposed. What's worse, the copper body will also age, which means that the surface of the organic solderability film or the copper body has changed significantly. This application uses the sample body exposed or the organic solderability film completely consumed. When one of these two situations occurs, the aging test is terminated and the current status data of the sample is recorded, including the surface morphology of the sample body and the organic solderability film, as well as the thickness of the organic solderability film.

[0062] S170: comparing the current state data of the organic solderability film with a preset threshold value to detect the quality of the organic solderability film.

[0063] Based on the data of the initial state and different aging time periods, the maximum storage time of the OSP film and the relationship between the change of film thickness over time are calculated based on the time, so as to evaluate the quality of the OSP film and complete the failure analysis of the OSP film.

[0064] Figure 6 An image of the surface observation area in the initial state is shown, Figure 7 An image of the surface observation area of the final state is shown, Figure 8 An image of the first cross-sectional observation area in the initial state is shown, Figure 9 An image of the first cross-sectional observation area of the final state is shown.

[0065] In summary, the failure analysis method for an organic solderability film provided in the embodiments of this application assesses the quality of the OSP film based on storage time by testing samples with the organic solderability film from both the surface observation area and multiple cross-sectional observation areas. The aging sample method discussed in this application precisely measures the effects of acceleration time and analysis time on the OSP film. Furthermore, a focused ion beam (FIB) method is used for cutting, enabling precise positioning and cutting to prepare the sample's cross-sectional observation area. This area is then inspected using a SEM, improving preparation and inspection accuracy.

[0066] The above description is merely an embodiment of the present application and is not intended to limit the scope of protection of the present application. For those skilled in the art, various modifications and variations of the present application are possible. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A failure analysis method for an organic solderability film, characterized in that: include: Obtaining a sample with an organic solderability film provided on its surface; wherein the organic solderability film is provided on the body of the sample; Marking a closed area on the surface of the sample as a surface observation area, and depositing a metal protective layer on the area outside the surface observation area on the sample; Cutting the area of the sample having the metal protective layer along any direction to form a first cross-sectional observation area; Detecting the surface observation area to obtain the surface morphology of the organic solderability film; detecting multiple observation points in the first cross-sectional observation area to respectively obtain the surface morphologies of the sample body and the organic solderability film, as well as the thickness of the organic solderability film, to obtain initial state data of the surface observation area, and using an average value of the data of the multiple observation points in the first cross-sectional observation area as the initial state data of the first cross-sectional observation area; Performing an aging test on the sample and observing whether the surface of the body is oxidized at preset intervals; detecting the surface observation area to obtain the surface morphology of the organic solderability film; cutting the area of the sample having the metal protective layer along any direction to form a second cross-sectional observation area; detecting multiple observation points in the second cross-sectional observation area to obtain the surface morphologies of the body and the organic solderability film of the sample, as well as the thickness of the organic solderability film, to obtain initial state data of the surface observation area, and using the average value of the data of the multiple observation points in the second cross-sectional observation area as the initial state data of the second cross-sectional observation area; An aging test is performed on the sample, and the surface of the body is observed to determine whether it is oxidized at preset intervals; the surface observation area is detected to obtain the surface morphology of the organic solderability film; the area of the sample having the metal protective layer is cut along any direction to form an N-th cross-sectional observation area; multiple observation points of the N-th cross-sectional observation area are detected to obtain the surface morphologies of the body and the organic solderability film of the sample, as well as the thickness of the organic solderability film, to obtain initial state data of the surface observation area, and the average value of the data of the multiple observation points of the N-th cross-sectional observation area is used as the initial state data of the N-th cross-sectional observation area; N is a natural number; When the sample is exposed from the body or the organic solderability film is completely consumed, recording the current state data of the sample; The quality of the organic solderability film is detected by comparing the current state data of the organic solderability film with a preset threshold value.

2. The failure analysis method of the organic solderability film according to claim 1, characterized in that: The method of obtaining a sample having an organic solderability protection film on its surface comprises: Cutting out the sample that meets the size requirements on the pad; The sample is cleaned.

3. The failure analysis method of the organic solderability film according to claim 2, characterized in that: After obtaining the sample with the organic solderability film provided on the surface, the method further comprises: placing the sample on a sample stage; The sample stage and the sample are connected by conductive glue.

4. The failure analysis method of the organic solderability film according to claim 1, wherein: The step of marking a closed area on the surface of the sample as a surface observation area and depositing a metal protective layer on an area outside the surface observation area on the sample comprises: identifying the surface observation area; The metal protection layer is deposited on the area outside the surface observation area of the sample by ion beam deposition.

5. The failure analysis method of the organic solderability film according to claim 1, wherein: The step of cutting the area of the sample having the metal protective layer along any direction to form a first cross-sectional observation area comprises: Using an ion beam probe to roughly cut the sample by focusing an ion beam to obtain a first cross-sectional observation area; The first cross-section observation area is smoothed.

6. The failure analysis method of the organic solderability film according to claim 1, wherein: The detecting of the surface observation area to obtain the surface morphology of the organic solderability film; detecting multiple observation points of the first cross-sectional observation area respectively to obtain the surface morphologies of the body of the sample and the organic solderability film, as well as the thickness of the organic solderability film, to obtain initial state data of the surface observation area, wherein the average value of the data of the multiple observation points of the first cross-sectional observation area as the initial state data of the first cross-sectional observation area includes: aligning an electron beam probe with and magnifying the surface observation area to obtain the surface morphology of the organic solderability film; The electron beam probe is aligned with and magnified at the first cross-sectional observation area to obtain the surface morphology of the body of the sample and the organic solderability film, as well as the thickness of the organic solderability film.

7. The failure analysis method of the organic solderability film according to claim 6, characterized in that: The aging test is performed on the sample, and the surface of the body is observed to determine whether it is oxidized at preset intervals; the surface observation area is detected to obtain the surface morphology of the organic solderability film; the area of the sample having the metal protective layer is cut along any direction to form a second cross-sectional observation area; a plurality of observation points of the second cross-sectional observation area are detected to obtain the surface morphologies of the body and the organic solderability film of the sample, as well as the thickness of the organic solderability film, to obtain initial state data of the surface observation area, wherein the average value of the data of the plurality of observation points of the second cross-sectional observation area as the initial state data of the second cross-sectional observation area includes: Placing the sample in an aging box and aging the sample according to a preset temperature and time; Taking out the sample at the preset time intervals to observe whether the surface of the body is oxidized; Observing the surface observation area of the sample to obtain the surface morphology of the body of the sample and the organic solderability film, as well as the thickness of the organic solderability film; Cutting the sample to form a second cross-sectional observation area, and obtaining the surface morphology of the sample body and the organic solderability film, as well as the thickness of the organic solderability film, by averaging initial state data of a plurality of observation points in the second cross-sectional observation area; After the observation is completed, the sample is placed in the aging box to continue aging.

8. The failure analysis method of the organic solderability film according to claim 7, wherein: Placing the sample in an aging box and aging the sample according to a preset temperature and time includes: The sample is aged at a temperature of 100° C. to 200° C. for a period of 2 to 6 hours.

9. The failure analysis method of the organic solderability film according to claim 7, wherein: After taking out the sample at the preset time interval and observing whether the surface of the body is oxidized, the method further includes: The surface of the first cross-sectional observation area is micro-processed to obtain the first cross-sectional observation area which is not oxidized.

10. The failure analysis method of the organic solderability film according to claim 1, wherein: The material of the body of the sample is copper, and the material of the metal protective layer is platinum.

Images