Interlayer shear strength test specimen for multilayer ceramic substrates and method for testing interlayer shear strength using the same

Abstract

The present invention relates to a specimen for testing the interlayer shear strength of a multilayer ceramic substrate formed by bonding a plurality of ceramic thin plates, comprising: an upper ceramic thin plate; a lower ceramic thin plate disposed below the upper ceramic thin plate; an intermediate ceramic thin plate disposed between the upper ceramic thin plate and the lower ceramic thin plate; a first intermediate ceramic thin plate disposed between the upper ceramic thin plate and the intermediate ceramic thin plate; a second intermediate ceramic thin plate disposed between the lower ceramic thin plate and the intermediate ceramic thin plate; and a bonding layer that bonds the plurality of ceramic thin plates together. According to the present invention, there is an effect of reliably testing the interlayer shear strength of a multilayer ceramic substrate formed by stacking a plurality of previously fired ceramic thin plates.

Description

Technology Field

[0001] The present invention relates to a specimen for testing the interlayer shear strength of a multilayer ceramic substrate and a method for testing shear strength using the same. Background Technology

[0002] Due to their excellent heat resistance, wear resistance, insulation, and mechanical strength properties, multilayer ceramic substrates are widely used as critical components replacing conventional printed circuit boards (PCBs), and demand for them continues to increase. These multilayer ceramic substrates are utilized as composite components containing active elements, such as semiconductor IC chips, and passive elements, such as capacitors, inductors, and resistors, or as single semiconductor IC packages. In particular, multilayer ceramic substrates are extensively used as critical components for PA module substrates, RF diode switches, filters, chip antennas, and various other electronic parts.

[0003] Multilayer ceramic substrates are formed by stacking multiple layers of ceramic thin sheets, and various types of wiring conductors are formed on each ceramic layer. Examples include pattern electrodes formed between ceramic layers, via electrodes formed through ceramic layers, and external electrodes. These wiring conductors must be arranged at a high density to optimize the function of the multilayer ceramic substrate, and for this purpose, highly precise manufacturing technology is required.

[0004] The manufacturing of multilayer ceramic substrates is generally carried out using the green sheet lamination method. This method involves preparing green sheets from a slurry formed from ceramic powder and an organic binder, then laminating and firing them. The green sheet lamination method is widely used in the manufacture of multilayer ceramic substrates because it can form multilayer structures of tens of layers or more and offers excellent surface smoothness and airtightness. However, this method can present various problems due to shrinkage occurring during the ceramic firing process. In particular, since ceramics do not shrink uniformly during the firing process, dimensional deformation of the ceramic layers may occur, leading to deformation or distortion in the wiring conductors. Such deformation reduces the positional precision of external electrodes, causing difficulties in semiconductor packaging, such as in CSPs (chip size packages) and MCMs (multi-chip modules), which require high precision.

[0005] Figure 1 illustrates a multilayer ceramic substrate formed by stacking multiple ceramic thin plates that have been fired.

[0006] Accordingly, a multilayer ceramic substrate is proposed in which a plurality of ceramic green sheets as shown in FIG. 1 are each fired to form a plurality of ceramic thin plates, and then the plurality of ceramic thin plates are stacked to form a multilayer ceramic substrate. Specifically, at least one via electrode (12) may be formed on each ceramic thin plate (11), and a pattern electrode (13) that electrically connects the via electrodes (12) may be formed on one side of the ceramic thin plate (11). In addition, these plurality of ceramic thin plates (11) are bonded together through a bonding layer (14) to form a single multilayer ceramic substrate.

[0007] Figure 2 shows a cross-bonded specimen used in a shear bond strength test according to ISO 13124:2011.

[0008] Meanwhile, ISO 13124:2011, standard name “Fine ceramics (advanced ceramics, advanced technical ceramics) - Test method for interfacial bond strength of ceramic materials” discloses a test method for evaluating the bonding strength of the interface between ceramic materials. According to the above ISO 13124:2011, two rectangular rod-shaped ceramic specimens are arranged in an intersecting manner so as to be orthogonal to each other, and the contact surfaces of these specimens are bonded to form an intersecting bonded specimen. It is stipulated that the interfacial bonding strength is measured by applying a load to the intersecting bonded specimen to generate shear stress at the bonding interface (1).

[0009] Such cross-bonding specimens have the advantage of being able to evaluate the bonding strength at a single bonding interface through a relatively simple test device, and are mainly used to evaluate bonding characteristics between single ceramic members or bonding characteristics of the bonding interface (1) of the material itself.

[0010] However, since the test method according to ISO 13124:2011 above basically has a structure based on a single-layer bonding interface, there are limitations in evaluating the interlayer shear strength of a multilayer ceramic substrate formed by stacking multiple ceramic thin plates. That is, when performing an interlayer shear strength test of a multilayer ceramic substrate using the cross-bonding specimen shown in FIG. 2, the stress generated by the test load is concentrated at a specific single bonding interface (1), and it is difficult to adequately reflect the stress transfer state at multiple interlayer interfaces existing in an actual multilayer ceramic substrate.

[0011] In addition, in multilayer ceramic substrates, adjacent ceramic sheets are often bonded through a bonding layer containing glass components, but if the cross-bonding specimen structure of ISO 13124:2011 is applied as is, the bonding layer itself may fracture brittlely before shear failure occurs at the interlayer interface. As a result, there is a concern that the fracture characteristics of the bonding layer material, rather than the interlayer bonding strength between the ceramic sheets that is actually to be evaluated, may be significantly reflected in the test results.

[0012] Consequently, the conventional shear adhesion strength test method according to ISO 13124:2011 has limitations in that it does not sufficiently reflect the structural characteristics of multilayer ceramic substrates and is unsuitable for accurately and reproducibly evaluating interlayer shear strength. Prior art literature

[0013] Republic of Korea Registered Patent No. 10-0229082 The problem to be solved

[0014] The objective of the present invention is to solve the aforementioned conventional problems by providing a specimen for testing the interlayer shear strength of a multilayer ceramic substrate and a method for testing shear strength using the same, which can reliably test the interlayer shear strength of a multilayer ceramic substrate formed by stacking a plurality of previously fired ceramic thin plates. means of solving the problem

[0015] The above objective is achieved, according to the present invention, by a specimen for interlayer shear strength testing of a multilayer ceramic substrate formed by bonding a plurality of ceramic thin plates, comprising: an upper ceramic thin plate; a lower ceramic thin plate disposed below the upper ceramic thin plate; an intermediate ceramic thin plate disposed between the upper ceramic thin plate and the lower ceramic thin plate; a first intermediate ceramic thin plate disposed between the upper ceramic thin plate and the intermediate ceramic thin plate; a second intermediate ceramic thin plate disposed between the lower ceramic thin plate and the intermediate ceramic thin plate; and a bonding layer that bonds the plurality of ceramic thin plates together.

[0016] In addition, the bonding layer may be formed of an organic or inorganic material.

[0017] In addition, a plurality of the above ceramic thin plates can be formed into a rectangular bar shape.

[0018] Additionally, the intermediate ceramic thin plate includes a first intermediate ceramic thin plate and a second intermediate ceramic thin plate, wherein the first intermediate ceramic thin plate is disposed between the upper ceramic thin plate and the first intermediate ceramic thin plate and between the upper ceramic thin plate and the second intermediate ceramic thin plate, respectively, and the second intermediate ceramic thin plate may be disposed between the lower ceramic thin plate and the first intermediate ceramic thin plate and between the lower ceramic thin plate and the second intermediate ceramic thin plate, respectively.

[0019] In addition, the first intermediate ceramic thin plate and the second intermediate ceramic thin plate may be aligned and arranged with respect to the intermediate ceramic thin plate.

[0020] Additionally, the first intermediate ceramic thin plate may be formed and arranged in multiple numbers between the upper ceramic thin plate and the first intermediate ceramic thin plate and between the upper ceramic thin plate and the second intermediate ceramic thin plate, respectively, and the second intermediate ceramic thin plate may be formed and arranged in multiple numbers between the lower ceramic thin plate and the first intermediate ceramic thin plate and between the lower ceramic thin plate and the second intermediate ceramic thin plate, respectively.

[0021] In addition, the first intermediate ceramic thin plate and the second intermediate ceramic thin plate may be arranged so as not to be aligned with each other based on the intermediate ceramic thin plate.

[0022] The above objective is achieved by a shear strength test method using a specimen for an interlayer shear strength test of a multilayer ceramic substrate formed by bonding a plurality of ceramic thin plates according to the present invention, comprising: a preparation step of preparing said specimen; and a test step of performing a shear strength test using said specimen, wherein said specimen comprises: an upper ceramic thin plate; a lower ceramic thin plate disposed below the upper ceramic thin plate; an intermediate ceramic thin plate disposed between the upper ceramic thin plate and the lower ceramic thin plate; a first intermediate ceramic thin plate disposed between the upper ceramic thin plate and the intermediate ceramic thin plate; a second intermediate ceramic thin plate disposed between the lower ceramic thin plate and the intermediate ceramic thin plate; and a bonding layer that bonds a plurality of said ceramic thin plates together, said intermediate ceramic thin plate comprises a first intermediate ceramic thin plate and a second intermediate ceramic thin plate, and said test step performs said shear strength test by tensile the first intermediate ceramic thin plate and the second intermediate ceramic thin plate in opposite directions while maintaining them in a parallel state.

[0023] In addition, the bonding layer may be formed of an organic or inorganic material.

[0024] In addition, a plurality of the above ceramic thin plates can be formed into a rectangular bar shape.

[0025] Additionally, the first intermediate ceramic thin plate may be disposed between the upper ceramic thin plate and the first intermediate ceramic thin plate and between the upper ceramic thin plate and the second intermediate ceramic thin plate, respectively, and the second intermediate ceramic thin plate may be disposed between the lower ceramic thin plate and the first intermediate ceramic thin plate and between the lower ceramic thin plate and the second intermediate ceramic thin plate, respectively.

[0026] In addition, the first intermediate ceramic thin plate and the second intermediate ceramic thin plate may be aligned and arranged with respect to the intermediate ceramic thin plate.

[0027] Additionally, the first intermediate ceramic thin plate may be formed and arranged in multiple numbers between the upper ceramic thin plate and the first intermediate ceramic thin plate and between the upper ceramic thin plate and the second intermediate ceramic thin plate, respectively, and the second intermediate ceramic thin plate may be formed and arranged in multiple numbers between the lower ceramic thin plate and the first intermediate ceramic thin plate and between the lower ceramic thin plate and the second intermediate ceramic thin plate, respectively.

[0028] In addition, the first intermediate ceramic thin plate and the second intermediate ceramic thin plate may be arranged so as not to be aligned with each other based on the intermediate ceramic thin plate. Effects of the invention

[0029] According to the present invention, there is an effect of reliably testing the interlayer shear strength of a multilayer ceramic substrate formed by stacking a plurality of previously fired ceramic thin plates.

[0030] Meanwhile, the effects of the present invention are not limited to those mentioned above, and various effects may be included within the scope obvious to a person skilled in the art from the contents described below. Brief explanation of the drawing

[0031] FIG. 1 illustrates a multilayer ceramic substrate formed by stacking a plurality of previously fired ceramic thin plates. Figure 2 shows cross-bonded specimens in the shear bond strength test according to ISO 13124:2011, and FIG. 3 illustrates, in its entirety, a specimen for an interlayer shear strength test of a multilayer ceramic substrate according to one embodiment of the present invention, and FIGS. 4 to 7 illustrate examples of specimens for interlayer shear strength testing of a multilayer ceramic substrate according to one embodiment of the present invention, and FIG. 8 is a flowchart of a shear strength test method using a specimen for interlayer shear strength testing of a multilayer ceramic substrate according to one embodiment of the present invention. Specific details for implementing the invention

[0032] Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that in assigning reference numerals to the components of each drawing, the same components are given the same reference numeral whenever possible, even if they are shown in different drawings.

[0033] In addition, when describing embodiments of the present invention, if it is determined that a detailed description of related known configurations or functions would hinder understanding of the embodiments of the present invention, such detailed description is omitted.

[0034] In addition, terms such as first, second, A, B, (a), (b), etc., may be used when describing the components of the embodiments of the present invention. These terms are used merely to distinguish the components from other components, and the essence, order, or sequence of the components is not limited by such terms.

[0036] From now on, with reference to the attached drawings, a specimen (100) for testing the interlayer shear strength of a multilayer ceramic substrate according to one embodiment of the present invention will be described in detail.

[0037] FIG. 3 illustrates a specimen (100) for interlayer shear strength testing of a multilayer ceramic substrate according to one embodiment of the present invention, and FIG. 4 to 7 illustrate examples of specimens (100) for interlayer shear strength testing of a multilayer ceramic substrate according to one embodiment of the present invention.

[0038] Referring to FIGS. 3 to 7, the present invention relates to a specimen (100) for interlayer shear strength testing of a multilayer ceramic substrate formed by joining a plurality of ceramic thin plates (110). Each ceramic thin plate (110) used in the present invention may be formed to conform to the shape and dimension specifications of a unit test specimen defined in ISO 13124:2011. The specimen (100) for interlayer shear strength testing of a multilayer ceramic substrate in the present invention may refer to an assembly formed integrally by joining a plurality of ceramic thin plates (110) as described above.

[0039] More specifically, such a specimen may include a plurality of ceramic thin plates (110) and a bonding layer (120).

[0040] The multilayer ceramic substrate in the present invention is characterized by not manufacturing the multilayer ceramic substrate by stacking and firing a plurality of ceramic green sheets as in the conventional method, but by manufacturing a plurality of ceramic thin sheets (110) by firing each of the plurality of ceramic green sheets, and then manufacturing the multilayer ceramic substrate by stacking and bonding each of the manufactured ceramic thin sheets (110).

[0041] Accordingly, the temperature at which the ceramic green sheet is fired to manufacture a plurality of ceramic thin sheets (110) in the present invention may be 1000°C to 1700°C, and the firing may be performed for 1 to 5 hours in an oxygen-free reducing environment or an atmospheric environment. In addition, the ceramic thin sheet (110) manufactured by firing the ceramic green sheet may have a thickness of 30 µm to 300 µm.

[0042] These multiple ceramic sheets (110) can be formed with the same shape, for example, each can be formed in the shape of a rectangular bar, and strength can be calculated based on their area.

[0043] These multiple ceramic thin plates (110) can be joined through a bonding layer (120) in a perpendicular manner to each other to form a symmetric cross structure. At this time, the multiple ceramic thin plates (110) must be joined within a right angle ±1° error range.

[0044] The bonding layer (120) is formed by joining a plurality of ceramic thin plates (110) so as to be orthogonal to each other, and can be formed of an organic or inorganic material.

[0045] Specifically, this bonding layer (120) is formed by applying a bonding agent to one side of a ceramic thin plate, and it is preferable that the bonding agent be made of a material that does not affect via electrodes or pattern electrodes. This bonding agent may be an inorganic material and / or an organic material, and if the bonding agent is an inorganic material, it may include glass, ceramic, etc., and if the bonding agent is an organic material, it may include a polymer such as epoxy, but is not limited thereto. Meanwhile, the thickness of the bonding layer (120) may be 2㎛ to 100㎛.

[0046] The specimen of the present invention can be manufactured such that a plurality of ceramic thin plates (110) are bonded together in a mutually orthogonal manner with a bonding layer (120) interposed therebetween, and then sintering or heat treatment is performed to melt the bonding layer (120), and subsequently cooling is performed so that the ceramic thin plates (110) are firmly bonded together. At this time, the sintering or heat treatment is performed within a temperature range that does not substantially affect the ceramic thin plates (110), thereby effectively preventing deformation or cracking from occurring in the ceramic thin plates (110) themselves.

[0047] Meanwhile, a plurality of ceramic thin plates (110) may include an upper ceramic thin plate (111), a lower ceramic thin plate (112), an intermediate ceramic thin plate (113), and an intermediate ceramic thin plate (114).

[0048] The upper ceramic thin plate (111) is a thin plate placed on the upper part of the specimen and can be configured to respond to load application and support conditions during testing.

[0049] The lower ceramic thin plate (112) is a thin plate placed parallel to the upper ceramic thin plate (111) at the bottom of the specimen, and can form a stacked structure of the specimen by being placed in a position opposite to the upper ceramic thin plate (111).

[0050] The intermediate ceramic plate (113) is a plate positioned between the upper ceramic plate (111) and the lower ceramic plate (112), and is positioned parallel to the upper ceramic plate (111) and the lower ceramic plate (112), respectively, and can be configured to provide a target structure to which shear stress acts during an interlayer shear strength test.

[0051] The intermediate ceramic plate (114) is positioned between the upper ceramic plate (111) and the intermediate ceramic plate (113), or between the lower ceramic plate (112) and the intermediate ceramic plate (113), and is positioned in a direction orthogonal to the upper ceramic plate (111), the lower ceramic plate (112), and the intermediate ceramic plate (113), and can be applied as a configuration to form a shear load transfer path or control stress distribution on the upper and lower sides.

[0052] Specifically, the first intermediate ceramic sheet (1141) can be placed between the upper ceramic sheet (111) and the intermediate ceramic sheet (113), and the second intermediate ceramic sheet (1142) can be placed between the lower ceramic sheet (112) and the intermediate ceramic sheet (113).

[0053] Referring to FIGS. 3 and 4, the intermediate ceramic sheet (113) may include a first intermediate ceramic sheet (1131) and a second intermediate ceramic sheet (1132).

[0054] At this time, the first intermediate ceramic sheet (1141) may include a first-1 intermediate ceramic sheet (1141-1) and a first-2 intermediate ceramic sheet (1141-2). The first-1 intermediate ceramic sheet (1141-1) may be positioned between the upper ceramic sheet (111) and the first intermediate ceramic sheet (1131), and may be positioned in a direction orthogonal to the upper ceramic sheet (111) and the first intermediate ceramic sheet (1131). Additionally, the first-2 intermediate ceramic sheet (1141-2) may be positioned between the upper ceramic sheet (111) and the second intermediate ceramic sheet (1132), and may be positioned in a direction orthogonal to the upper ceramic sheet (111) and the second intermediate ceramic sheet (1132).

[0055] Additionally, the second intermediate ceramic sheet (1142) may include a second-first intermediate ceramic sheet (1142-1) and a second-second intermediate ceramic sheet (1142-2). The second-first intermediate ceramic sheet (1142-1) may be positioned between the lower ceramic sheet (112) and the first intermediate ceramic sheet (1131), and may be positioned in a direction orthogonal to the lower ceramic sheet (112) and the first intermediate ceramic sheet (1131). Additionally, the second-second intermediate ceramic sheet (1142-2) may be positioned between the lower ceramic sheet (112) and the second intermediate ceramic sheet (1132), and may be positioned in a direction orthogonal to the lower ceramic sheet (112) and the second intermediate ceramic sheet (1132).

[0056] At this time, the first-1 mediating ceramic thin plate (1141-1) and the second-1 mediating ceramic thin plate (1142-1) may be arranged aligned with each other based on the stacking direction, and the first-2 mediating ceramic thin plate (1141-2) and the second-2 mediating ceramic thin plate (1142-2) may also be arranged aligned with each other based on the stacking direction.

[0057] This is a structure in which an intermediate ceramic thin plate (114) is arranged in a corresponding manner on the upper and lower sides based on the intermediate ceramic thin plate (113), so that the phenomenon of shear load being locally concentrated on a specific bonding layer (120) can be mitigated, which may be advantageous for more stably evaluating the shear failure characteristics of the bonding layer (120) or the interlayer interface.

[0058] Also, referring to FIG. 5, each of the first-1 intermediate ceramic thin plate (1141-1), the first-2 intermediate ceramic thin plate (1141-2), the second-1 intermediate ceramic thin plate (1142-1), and the second-2 intermediate ceramic thin plate (1142-2) is formed in a direction orthogonal to the upper ceramic thin plate (111), the lower ceramic thin plate (112), and the intermediate ceramic thin plate (113), and each can be arranged in multiple numbers.

[0059] In this case, the first-1 mediating ceramic thin plate (1141-1) and the second-1 mediating ceramic thin plate (1142-1) can be formed in the same number to correspond to each other, and the first-2 mediating ceramic thin plate (1141-2) and the second-2 mediating ceramic thin plate (1142-2) can also be formed in the same number to correspond to each other.

[0060] Furthermore, the first-1 mediating ceramic thin plate (1141-1), the first-2 mediating ceramic thin plate (1141-2), the second-1 mediating ceramic thin plate (1142-1), and the second-2 mediating ceramic thin plate (1142-2) may all be formed in the same number.

[0061] According to this, since the total area of ​​the bond interface to which the shear load is transmitted can be expanded, it can contribute to mitigating the phenomenon of stress concentration at a specific bond interface when a shear load is applied.

[0062] Also, referring to FIG. 6, the first-1 intermediate ceramic thin plate (1141-1) and the second-1 intermediate ceramic thin plate (1142-1) may be arranged so as not to be aligned with each other based on the stacking direction, and the first-2 intermediate ceramic thin plate (1141-2) and the second-2 intermediate ceramic thin plate (1142-2) may also be arranged so as not to be aligned with each other based on the stacking direction.

[0063] According to this, since the positions of the bonding interfaces are distributed offset from each other in the stacking direction, the tendency for stress to concentrate at specific locations when a shear load is applied can be mitigated. In addition, since the pattern of shear stress transfer at the interlayer interface can vary depending on the spacing or degree of offset of the intermediate ceramic thin plates (114), it can be used to compare and evaluate the trend of change in shear strength characteristics according to the arrangement conditions.

[0064] Meanwhile, referring to FIG. 7, the intermediate ceramic thin plate (113) may be formed and arranged in a single unit. In this case, the structure in which the intermediate ceramic thin plate (113) is interposed between the upper ceramic thin plate (111) and the lower ceramic thin plate (112) may be maintained, and during testing, the interlayer shear strength evaluation may be performed by applying relative displacement based on the intermediate ceramic thin plate (113) while setting constraint conditions on the upper side and the lower side.

[0066] Now, with reference to the attached drawings, a shear strength test method (S100) using a specimen for interlayer shear strength testing of a multilayer ceramic substrate according to one embodiment of the present invention will be described in detail.

[0067] FIG. 8 is a flowchart of a shear strength test method (S100) using a specimen for interlayer shear strength testing of a multilayer ceramic substrate according to one embodiment of the present invention.

[0068] Referring to FIG. 8, a shear strength test method (S100) using a specimen for interlayer shear strength testing of a multilayer ceramic substrate according to one embodiment of the present invention may include a preparation step (S110) and a test step (S120).

[0069] The preparation step (S110) is the step of preparing the specimen to be used for the shear strength test.

[0070] In the preparation step (S110), a ceramic green sheet is first prepared, and then the ceramic green sheet is fired to manufacture a plurality of ceramic thin plates (110). Subsequently, a bonding layer (120) can be formed by applying a bonding agent to the bonding surface of the manufactured plurality of ceramic thin plates (110). Next, a specimen (100) for interlayer shear strength testing of a multilayer ceramic substrate can be manufactured by bonding the plurality of ceramic thin plates (110) with the bonding layer (120) formed thereon while they are arranged orthogonally to each other. At this time, the specimen can be formed in various shapes depending on the purpose of the shear strength test to be performed or the configuration of the test device.

[0071] Below, regarding the specimen (100) for the interlayer shear strength test of a multilayer ceramic substrate, separate explanations are omitted for matters identical to those already explained.

[0072] The test step (S120) is a step of measuring the interlayer shear strength of a multilayer ceramic substrate using a prepared specimen.

[0073] Each ceramic thin plate (110) used in the test step (S120) is configured to correspond to a unit test specimen defined in ISO 13124:2011, and the dimensions of the ceramic thin plate (110) can be defined as the length of the ceramic thin plate (110), the width of the ceramic thin plate (110), and the thickness of the ceramic thin plate (110), and the dimensions can be measured before the test to ensure the reliability of the test results.

[0074] In the test phase (S120), a compression tester capable of accurate load control may be used, and for example, it is desirable to use a tester with load measurement accuracy at the ISO 7500-1:2004 Class 1 level.

[0075] In addition, a data recording device capable of recording load-versus-displacement or load-versus-time graph data can be installed to verify displacement or time changes according to the load during the test.

[0076] Meanwhile, dimensional measuring tools such as micrometers can be used to precisely measure the bonding area, width, and thickness of the specimen, and dedicated fixtures can be used to stably support and align the specimen on the testing machine.

[0077] In the test phase (S120), to measure the shear bond strength, the test mode and test speed are first set.

[0078] Specifically, a mode for measuring shear bonding strength can be selected as a test mode of the compression testing machine, and the test speed can be set to a constant cross-head displacement speed. Meanwhile, although the present invention has been described primarily for the measurement of interlaminar shear strength, it is also possible to measure tensile bond strength using the specimen of the present invention.

[0079] Next, a compression load is applied to the specimen using a compression testing machine, and the test data is recorded.

[0080] Specifically, the compressive load applied to the specimen can be continuously increased, and the load can be applied such that shear stress acts on the bonding interface depending on the placement direction of the specimen and the structure of the fixture. During this process, load and displacement data can be automatically recorded.

[0081] Subsequently, if separation or fracture occurs at the bonding interface of the specimen, the maximum load at that point is measured.

[0082] Specifically, the maximum load at the point where the bonding interface fails can be obtained as the shear failure load Pc.

[0083] Next, the test results are calculated using the acquired maximum load. The shear bonding strength τ can be defined according to the following mathematical formula 1.

[0084]

[0085] Here, P c is the maximum load at shear failure, and A2 is the joint area where shear stress acts.

[0086] Meanwhile, tensile bonding strength σ t It can be defined according to the following mathematical formula 2.

[0087]

[0088] Here, P cis the maximum load at tensile failure, and A1 is the joint area where tensile stress acts.

[0089] Strength values ​​can be calculated for each of the multiple test results, and statistical processing such as the mean and standard deviation may be performed as needed.

[0090] Next, you can organize the test results and write a test results report.

[0091] The above test result report may include information regarding specimen dimensions, including length, width, and thickness of the specimen, test mode and test speed, maximum load and tensile or shear strength values, failure mode and interface characteristics, and test conditions and test equipment used.

[0092] Meanwhile, when using the specimen (100) for the interlayer shear strength test of the multilayer ceramic substrate of the present invention, the shear strength test can be performed in different ways depending on the structure of the specimen.

[0093] First, as illustrated in FIGS. 4 to 6, when the intermediate ceramic thin plate (113) has a structure including a first intermediate ceramic thin plate (1131) and a second intermediate ceramic thin plate (1132), the shear strength test can be performed with the first intermediate ceramic thin plate (1131) and the second intermediate ceramic thin plate (1132) each supported by a fixture of the test machine. At this time, the first intermediate ceramic thin plate (1131) and the second intermediate ceramic thin plate (1132) are arranged to maintain a parallel state with each other and can be constrained to maintain the parallel state even during the test. Subsequently, by applying a tensile load in opposite directions to the first intermediate ceramic thin plate (1131) and the second intermediate ceramic thin plate (1132), shear stress can be generated at the bonding interface between the intermediate ceramic thin plate (113), the intermediate ceramic thin plate (114) bonded thereto, and the bonding layer (120). In this manner, shear failure behavior occurring at the interlayer interface of the specimen can be induced, and the interlayer shear strength resulting therefrom can be measured.

[0094] At this time, the upper ceramic thin plate (111) and the lower ceramic thin plate (112) form a shear stress transfer path according to the relative displacement of the first intermediate ceramic thin plate (1131) and the second intermediate ceramic thin plate (1132), and the intermediate ceramic thin plate (114) can perform the role of dispersing the shear load along the bonding interface. Accordingly, a test environment can be implemented so that multiple interlayer interfaces receive a shear load under conditions similar to those of an actual multilayer ceramic substrate.

[0095] Meanwhile, as illustrated in FIG. 7, in the case where the intermediate ceramic thin plate (113) is formed and arranged in a single structure, the shear strength test can be performed with the specimen positioned vertically on the fixture of the tester. In this case, the upper ceramic thin plate (111) and the lower ceramic thin plate (112) are positioned to be restrained by the support of the tester, and a compressive load can be applied vertically to the intermediate ceramic thin plate (113). Accordingly, shear stress is generated at the bonding interface between the intermediate ceramic thin plate (113), the intermediate ceramic thin plate (114) bonded thereto, and the bonding layer (120), thereby allowing the interlayer shear strength test to be performed.

[0096] As such, the specimen (100) for testing the interlayer shear strength of the multilayer ceramic substrate of the present invention can be applied in various test methods depending on the configuration of the intermediate ceramic thin plate (113), and each test method can be configured to evaluate the shear strength characteristics at the interlayer bonding interface by reflecting the structural characteristics of the specimen.

[0098] Although all components constituting the embodiments of the present invention have been described above as being combined or operating in combination, the present invention is not necessarily limited to such embodiments. That is, within the scope of the purpose of the present invention, all components may be selectively combined in one or more ways to operate.

[0099] Furthermore, terms such as "include," "compose," or "have" described above, unless specifically stated otherwise, mean that the relevant component may be inherent; therefore, they should be interpreted as allowing for the inclusion of additional components rather than excluding them. All terms, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains, unless otherwise defined. Commonly used terms, such as those defined in advance, should be interpreted in accordance with their meaning in the context of the relevant technology and should not be interpreted in an ideal or overly formal sense unless explicitly defined in the present invention.

[0100] Furthermore, the above description is merely an illustrative explanation of the technical concept of the present invention, and those skilled in the art to which the present invention pertains will be able to make various modifications and variations within the scope of the essential characteristics of the present invention.

[0101] Accordingly, the embodiments disclosed in this invention are intended to illustrate, not limit, the technical concept of the invention, and the scope of the technical concept of the invention is not limited by these embodiments. The scope of protection of this invention shall be interpreted by the claims below, and all technical concepts within an equivalent scope shall be interpreted as being included within the scope of rights of this invention. Explanation of the symbols

[0102] 100: Specimen for testing the interlayer shear strength of a multilayer ceramic substrate according to one embodiment of the present invention 110 : Ceramic sheet 111: Upper ceramic sheet 112: Lower ceramic sheet 113 : Intermediate ceramic sheet 1131: 1st intermediate ceramic sheet 1132: Second intermediate ceramic sheet 114: Medium ceramic sheet 1141: First mediating ceramic sheet 1141-1 : Section 1-1 Mediatory Ceramic Sheet 1141-2 : 1st-2nd Parameter Ceramic Sheet 1142: Second mediating ceramic sheet 1142-1 : Section 2-1 Mediatory Ceramic Sheet 1142-2 : Section 2-2 Parameter ceramic sheet 120: Bonding layer

Claims

Claim 1 A specimen for testing the interlayer shear strength of a multilayer ceramic substrate formed by bonding a plurality of ceramic thin plates, comprising: an upper ceramic thin plate; a lower ceramic thin plate disposed below the upper ceramic thin plate; an intermediate ceramic thin plate disposed between the upper ceramic thin plate and the lower ceramic thin plate; a first intermediate ceramic thin plate disposed between the upper ceramic thin plate and the intermediate ceramic thin plate; a second intermediate ceramic thin plate disposed between the lower ceramic thin plate and the intermediate ceramic thin plate; and a bonding layer that bonds the plurality of ceramic thin plates together, wherein the intermediate ceramic thin plate comprises a first intermediate ceramic thin plate and a second intermediate ceramic thin plate, wherein the first intermediate ceramic thin plate is disposed between the upper ceramic thin plate and the first intermediate ceramic thin plate and between the upper ceramic thin plate and the second intermediate ceramic thin plate, respectively, and the second intermediate ceramic thin plate is disposed between the lower ceramic thin plate and the first intermediate ceramic thin plate and between the lower ceramic thin plate and the second intermediate ceramic thin plate, respectively. Claim 2 The specimen for interlayer shear strength testing of a multilayer ceramic substrate according to claim 1, wherein the bonding layer is formed of an organic or inorganic material. Claim 3 In claim 1, the plurality of the ceramic thin plates are specimens for interlayer shear strength testing of a multilayer ceramic substrate, formed in a rectangular bar shape. Claim 4 delete Claim 5 A specimen for testing the interlayer shear strength of a multilayer ceramic substrate according to claim 1, wherein the first intermediate ceramic thin plate and the second intermediate ceramic thin plate are aligned and arranged with respect to the intermediate ceramic thin plate. Claim 6 A specimen for testing the interlayer shear strength of a multilayer ceramic substrate according to claim 5, wherein the first intermediate ceramic thin plate is formed and arranged in a plurality between the upper ceramic thin plate and the first intermediate ceramic thin plate and between the upper ceramic thin plate and the second intermediate ceramic thin plate, respectively, and the second intermediate ceramic thin plate is formed and arranged in a plurality between the lower ceramic thin plate and the first intermediate ceramic thin plate and between the lower ceramic thin plate and the second intermediate ceramic thin plate, respectively. Claim 7 A specimen for interlayer shear strength testing of a multilayer ceramic substrate according to claim 1, wherein the first intermediate ceramic thin plate and the second intermediate ceramic thin plate are arranged so as not to be aligned with each other with respect to the intermediate ceramic thin plate. Claim 8 A shear strength test method using a specimen for interlayer shear strength testing of a multilayer ceramic substrate formed by bonding a plurality of ceramic thin plates, comprising: a preparation step of preparing said specimen; The test step includes performing a shear strength test using the above specimen, wherein the specimen comprises an upper ceramic thin plate, a lower ceramic thin plate disposed below the upper ceramic thin plate, an intermediate ceramic thin plate disposed between the upper ceramic thin plate and the lower ceramic thin plate, a first intermediate ceramic thin plate disposed between the upper ceramic thin plate and the intermediate ceramic thin plate, a second intermediate ceramic thin plate disposed between the lower ceramic thin plate and the intermediate ceramic thin plate, and a bonding layer that bonds a plurality of the ceramic thin plates together, wherein the intermediate ceramic thin plate comprises a first intermediate ceramic thin plate and a second intermediate ceramic thin plate, and the test step performs the shear strength test by tensile the first intermediate ceramic thin plate and the second intermediate ceramic thin plate in opposite directions while maintaining them in a parallel state, wherein the first intermediate ceramic thin plate is disposed between the upper ceramic thin plate and the first intermediate ceramic thin plate and between the upper ceramic thin plate and the second intermediate ceramic thin plate, respectively, and the second intermediate ceramic thin plate is disposed between the lower ceramic thin plate and the first intermediate ceramic thin plate and between the lower ceramic thin plate and the second A shear strength testing method using specimens for interlayer shear strength testing of multilayer ceramic substrates, each disposed between intermediate ceramic thin plates. Claim 9 A shear strength test method using a specimen for interlayer shear strength testing of a multilayer ceramic substrate, wherein the bonding layer is formed of an organic or inorganic material, in accordance with claim 8. Claim 10 A shear strength test method using a specimen for interlayer shear strength testing of a multilayer ceramic substrate, wherein, in claim 8, a plurality of the ceramic thin plates are formed in a rectangular bar shape. Claim 11 delete Claim 12 A shear strength test method using a specimen for an interlayer shear strength test of a multilayer ceramic substrate according to claim 8, wherein the first intermediate ceramic thin plate and the second intermediate ceramic thin plate are aligned and arranged with respect to the intermediate ceramic thin plate. Claim 13 A shear strength test method using a specimen for an interlayer shear strength test of a multilayer ceramic substrate according to claim 12, wherein the first intermediate ceramic thin plate is formed and arranged in a plurality between the upper ceramic thin plate and the first intermediate ceramic thin plate and between the upper ceramic thin plate and the second intermediate ceramic thin plate, respectively, and the second intermediate ceramic thin plate is formed and arranged in a plurality between the lower ceramic thin plate and the first intermediate ceramic thin plate and between the lower ceramic thin plate and the second intermediate ceramic thin plate, respectively. Claim 14 A shear strength test method using a specimen for an interlayer shear strength test of a multilayer ceramic substrate according to claim 8, wherein the first intermediate ceramic thin plate and the second intermediate ceramic thin plate are arranged so as not to be aligned with each other with respect to the intermediate ceramic thin plate.

Images