Hybrid test socket

By designing a hybrid test socket that combines the advantages of spring-loaded and rubber-loaded types, the problems of poor noise shielding, low coaxial alignment, and insufficient temperature stability of traditional sockets in high-speed signal testing are solved, thereby improving the versatility and durability of the contact pins.

CN121079596APending Publication Date: 2025-12-05HICON CO LTD +2
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Patent Information

Application Number
CN202580000518.1
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Priority Date
2024-04-04
Filing Date
2025-03-06
Publication Date
2025-12-05

AI Technical Summary

Technical Problem

In the existing technology, traditional spring-pin type and rubber type test sockets cannot meet customers' needs for spring contact pins of various lengths, and have problems such as poor noise shielding performance, low coaxial alignment of contact pins and insufficient temperature stability in high-speed signal testing.

Method used

A hybrid test socket is designed, combining the advantages of spring-pin and rubber types. It adopts an elastic insulator body and contacts. The contacts include: the main body includes: the main contact includes: the main contact includes: the main body includes: the socket body formed of elastic insulator, the contact pin and the spring. The contact pin is connected to the test device through the elastic insulator. One end of the contact contacts the terminal of the semiconductor device, and the other end contacts the pad of the test device, and it is elastic in the pressing direction.

Benefits of technology

It improves the coaxial alignment and noise shielding performance of the contact pins, reduces the impact of temperature changes, adapts to various types of contact pin requirements, extends the service life of the test socket, and reduces replacement costs.

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Abstract

An exemplary embodiment of the present invention discloses a hybrid test socket including: a body formed with a hole penetrating a first surface facing a terminal of a semiconductor device and a second surface facing a pad of a test device; a contact inserted into the hole, one end of the contact being in contact with a terminal of the semiconductor device, the other end of the contact being in contact with a pad of the test device, and having elasticity in a pressing direction; and a first member bonded to one end of the contact.
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Description

Technical Field

[0001] The present invention relates to a hybrid test socket, which includes a socket body made of an elastic insulator and elastic contact pins. Background Technology

[0002] Generally, BGA (ball grid array) or LGA (land grid array) type semiconductor ICs are ultimately inspected using inspection equipment to perform various electrical tests for characteristic measurement or defect inspection. At this time, test sockets are used to electrically connect the circuit pattern of the inspection printed circuit board installed in the inspection equipment to the lead balls or pads of the BGA or LGA type semiconductor IC.

[0003] Sufficient pressure must be applied to the contacts used in the test socket to ensure reliable contact with the IC leads (terminals). Therefore, the contacts must have sufficient elastic contact force within an appropriate range, and various types of contacts exist to meet these requirements.

[0004] In addition, multiple spring contacts are installed inside the housing of the test socket according to predetermined rules. Recently, various semiconductor devices have been developed, and customers' demand for spring contact pins of various lengths is constantly increasing. However, traditional pogo pin type spring contact pins often cannot meet customers' performance requirements.

[0005] For example, if the length of a traditional spring pin type spring contact is made longer according to customer requirements, the length of the contact pin that makes up the spring contact needs to be increased. At the same time, when designing the test socket, the depth of the pin hole to be inserted into the spring contact should also take into account the length of the contact pin and be machined to a diameter that can accommodate the width of the contact pin tip.

[0006] In order to process data quickly and reduce power consumption, spring contact pins have become increasingly thinner. Therefore, it is not only difficult to process long pin holes with a diameter suitable for the width of the contact pin tip, but also difficult to process long pin holes with a relatively small diameter suitable for the width of the contact pin tip. Moreover, the processing cost is very high and it is difficult to ensure quality.

[0007] In other words, traditional spring contact components cannot meet customers' requirements for spring contact pins of various lengths.

[0008] In addition, as another existing technology, there is a rubber type socket, which is composed of an insulating body and a conductive silicone part, wherein the insulating body is formed by curing insulating silicone and has elasticity, and the conductive silicone part corresponds to the terminals of the device and penetrates vertically through the insulating body.

[0009] In this type of rubber socket, if a silicone mixture of insulating silicone rubber and conductive powder in a predetermined ratio is placed into a mold, and a strong magnetic field is formed at the location where the conductive silicone part is formed, the conductive powder of the silicone mixture will gather at the location where the magnetic field is formed, and finally the molten silicone mixture will solidify, forming a predetermined arrangement of conductive silicone parts on the insulating body.

[0010] Compared to spring-loaded contacts, this type of rubber socket has a slower elastic response and loses elasticity during repeated testing, significantly reducing its lifespan. Therefore, its service life is short, requiring frequent replacement and increasing replacement costs. Furthermore, due to the characteristic that elastic durability decreases over time, the elastic repulsion force becomes zero or significantly reduced during prolonged continuous compression testing (more than a week), leading to short circuits. Therefore, it is difficult to conduct long-term testing.

[0011] In addition, the problem with rubber sockets is that their elasticity is greatly affected by temperature, and because they are mixed with insulating silicone or elastomer, the uniformity of resistance may be reduced. Summary of the Invention

[0012] Technical issues

[0013] Therefore, the object of the present invention is to provide a hybrid test socket that combines the advantages of spring pin type and rubber type to solve the above-mentioned problems.

[0014] One of the various objectives of this invention is to provide a test socket suitable for testing semiconductor devices using high-speed signals. Furthermore, another objective is to provide a test socket that improves noise shielding performance between adjacent contact pins and the coaxial alignment performance of the contact pins.

[0015] In addition, one of the various objectives of the present invention is to provide a test socket that can minimize the effects of temperature changes (high temperature stability).

[0016] One of the various objectives of this invention is to provide a hybrid test socket equipped with various types of contact pins according to customer performance requirements.

[0017] Methods for solving problems

[0018] Various embodiments for addressing the problems of the present invention can provide a hybrid test socket, comprising: a body having a hole formed through a first surface facing a terminal of a semiconductor device and a second surface facing a pad of a test device; a contact element inserted into the hole, one end of which contacts a terminal of the semiconductor device and the other end of which contacts a pad of the test device, and having elasticity in a pressing direction; and a first member bonded to one end of the contact element.

[0019] A feature of the present invention is that the first component is further disposed between the inner surface of the hole on the first surface side and around one end of the contact member.

[0020] The present invention may be characterized in that the main body includes: a base forming the shape of a test socket; and an elastic insulator filled inside the base and hardened to form elasticity, wherein the hole is formed by penetrating the elastic insulator.

[0021] The present invention may be characterized in that the contact element includes: a pair of contact pins; and a spring connected between the pair of contact pins for providing elasticity.

[0022] A feature of the present invention is that the pair of contact pins have the same shape and are connected in mutually intersecting directions.

[0023] The present invention may be characterized in that the contact needle includes: a main body portion having a predetermined width and thickness; a head portion formed at one end of the main body portion and in contact with the object being inspected; and a leg portion extending along the length direction of the main body portion in a direction opposite to that of the head portion.

[0024] A feature of the present invention is that the head is formed by winding a plate-shaped strip integrally formed with the main body.

[0025] A feature of the present invention is that the head has a plurality of pointed ends formed at its upper end.

[0026] A feature of the present invention is that the first member is disposed between at least a portion of the outer peripheral surface of the head and the inner surface of the hole.

[0027] A feature of the present invention is that the second surface is formed with a stepped hole, such that a step is formed toward the first surface.

[0028] A feature of this invention is that the diameter of the stepped hole is larger than the diameter of the hole.

[0029] A feature of the present invention is that the first component is bonded in a state where it is disposed on one end face of the contact member, and is wound around one end of the contact member and between the hole and hardened.

[0030] The present invention may be characterized in that the contact element includes: a contact needle; and an elastic member including conductive particles filled between the contact needle and the hole.

[0031] A feature of this invention is that the contact needle is formed by winding a plate-shaped strip.

[0032] A feature of the present invention is that the conductive particles are arranged by applying a magnetic force to the elastic member while the first member is being bonded together.

[0033] Each feature of the above embodiments may be combined in other embodiments without contradicting or being exclusive to other embodiments.

[0034] Invention Effects

[0035] According to various embodiments of the present invention, the upper shrinkage of the socket body made of an elastic insulator can be easily controlled.

[0036] In addition, the coaxial alignment of the contact pins can be improved by easily aligning the contact pin contacts located inside the socket body.

[0037] Furthermore, by improving the insulation between micro-pitches, noise during testing of high-speed signal semiconductor devices can be reduced.

[0038] The effects of the present invention are not limited to those described above, and those skilled in the art will clearly recognize other effects not mentioned from the following description. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of a hybrid test socket according to an embodiment of the present invention.

[0040] Figure 2 yes Figure 1 A schematic diagram of a spring contact pin.

[0041] Figure 3 yes Figure 2 An exploded 3D diagram.

[0042] Figures 4 to 8 yes Figure 2 A schematic diagram of the contact needle.

[0043] Figure 9 yes Figure 1 A schematic diagram of the manufacturing process of the hybrid test socket.

[0044] Figure 10 This is a schematic diagram of a hybrid test socket according to another embodiment of the present invention.

[0045] Figure 11 yes Figure 10 A schematic diagram of the contact needle. Detailed Implementation

[0046] Specific embodiments of the present invention will now be described with reference to the accompanying drawings. The detailed description provided below is intended to facilitate a thorough understanding of the methods, apparatus, and / or systems described herein. However, these are merely examples, and the invention is not limited thereto.

[0047] In describing embodiments of the present invention, detailed descriptions of well-known technologies related to the present invention will be omitted if it is determined that such detailed descriptions would obscure the essence of the invention. Furthermore, the terminology used below is defined with reference to the functionality of the present invention and may be changed according to the intention or habit of the user or operator. Therefore, definitions should be based on the entire contents of this specification.

[0048] The terminology used in this detailed description is for illustrative purposes only and should not be construed as limiting. Unless otherwise expressly stated, the singular form includes the meaning of the plural form.

[0049] In this specification, expressions such as “comprising” or “having” are intended to indicate certain features, numbers, steps, operations, elements, parts or combinations thereof, and should not be construed as excluding the presence or possibility of one or more other features, numbers, steps, operations, elements or parts or combinations thereof described.

[0050] Furthermore, when describing the constituent elements of embodiments of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the constituent elements from other constituent elements, and the nature, order, or sequence of the constituent elements are not limited by these terms.

[0051] Figure 1 This is a schematic diagram of a hybrid test socket according to an embodiment of the present invention.

[0052] Below, we will refer to Figure 1 This invention describes a hybrid test socket according to an embodiment of the present invention.

[0053] The hybrid test socket may include a body 10 and a contact 30. The body 10 may be formed of a material that is elastic when pressed by a semiconductor device, and the contact 30 may be provided with a component that is physically elastic (e.g., a spring) or formed of a component that is elastic in material (e.g., silicon powder mixed with conductive particles).

[0054] More specifically, the body 10 may have a hole that penetrates a first surface 11 facing a terminal of the semiconductor device and a second surface 12 facing a pad of the test device. The diameter d1 of the hole may be greater than or equal to the maximum diameter of the contact 30, such that the contact 30 is inserted into the hole.

[0055] That is, the contact 30 is inserted into the hole, with one end contacting the terminal of the semiconductor device and the other end contacting the pad of the test device, thereby providing elasticity in the pressing direction. The following will refer to... Figures 2 to 8 The detailed structure of the contact 30 according to an exemplary embodiment of the present invention will be described in more detail.

[0056] Additionally, the main body 10 may include: a base 11, 12 forming the shape of the test socket; and an elastic insulator 13 that is filled inside the base 11, 12 and then hardened to form an elastic structure.

[0057] The bases 11 and 12 can be formed from the first surface 11 and the second surface 53, and since the holes penetrate the first surface 11 and the second surface 12, they can penetrate the elastic insulator filling the interior of the bases 11 and 12.

[0058] Additionally, the first member 50 can be bonded to one end of the contact member 30. The one end of the contact member 30 can refer to the contact end of the contact member 30 located on the side of the first surface 11 that contacts the terminal of the semiconductor device when the contact member 30 is inserted into the hole.

[0059] The first member 50 can be disposed between the inner surface of the hole formed on the first surface 11 side and around one end of the contact member 30. The first member 50 is made of a soft material and is bonded to the contact member 30 while being disposed on one end face of the contact member 30. After being rolled into the area between the contact member 30 and the hole, it is hardened, thus allowing it to be disposed between the inner surface of the hole formed on the first surface 11 side and around one end of the contact member 30. Therefore, the first member 50 can be made of a silicon material whose properties change with heat.

[0060] By incorporating the first component 50, the upper retraction of the socket body 10, including the elastic insulator 13, can be easily controlled.

[0061] Unlike this embodiment, if the socket body 10 is made of a non-elastic material, such as a typical spring-pin type socket, the socket body will not shrink. Therefore, when the first member 50 is present, it will become a factor that hinders the shrinkage force of the spring contact pin. However, as mentioned above, this embodiment is a hybrid test socket that combines the advantages of a typical spring-pin type socket (pogo pin type socket) and a silicone rubber type socket. Therefore, durability can be improved by controlling the upper shrinkage of the socket body 10 using the first member 50.

[0062] In addition, the coaxial alignment of the contact member 30 can be improved by the first member 50 inside the body 10 including the elastic member, thereby improving the alignment of the contact portion of the contact member 30.

[0063] In addition, since the first component 50 is formed of silicon-based material, the insulation between micro-pitches is improved, thereby reducing noise during high-speed signal semiconductor device testing.

[0064] The first component 50 can be appropriately selected according to customer needs, and its Shore hardness is between 20A and 80A. When the hardness of the first component 50 deviates from the above range, it may be difficult to achieve the above effect.

[0065] For example, when the hardness of the first component 50 is higher than the above range, it may become a factor that hinders the elasticity of the contact 30, and a greater load may be required during testing. In this case, it may not meet the load-related performance conditions required by the customer, or the durability of the test socket may be reduced.

[0066] Additionally, a step hole h2 can be formed on the second surface 12. The step hole h2 can be formed by forming a step on the second surface 12 toward the first surface 11. In this shape of the step hole h2, the diameter d2 of the step hole h2 can be formed to be larger than the diameter d1 of the hole.

[0067] These stepped holes h2 can further improve the durability of the hybrid test socket, which is an exemplary embodiment of the present invention, by distributing the load of the test socket repeatedly pressed between the terminals of the semiconductor device and the pads of the test fixture. Without the stepped holes h2 as described in this embodiment, all the load around the contacts is absorbed by the body, which may result in reduced durability.

[0068] Figure 2 yes Figure 1 A schematic diagram of a spring contact pin. Figure 3 yes Figure 2 Decomposed 3D diagram, Figures 4 to 8 yes Figure 2 A schematic diagram of the contact needle.

[0069] Below, refer to Figures 1 to 8 This invention describes a hybrid test socket according to an embodiment of the present invention, as well as contacts suitable for the hybrid test socket.

[0070] The contact element 30 in this embodiment may include a spring contact pin structure. That is, it may include two contact pins 31 and 35, and a spring 33 that provides physical elasticity to the contact element 30.

[0071] More specifically, the contact 30 may include a pair of contact pins 31, 35 and a spring 33, with the spring 33 connected between the pair of contact pins 31, 35 to provide a spring force to the contact 30.

[0072] The spring 33 may be a helical compression spring having a predetermined length along the length direction of the contact member 30, and the spring 33 may provide a restoring force between the first contact pin 31 and the second contact pin 35 of the contact member 30, such that when the first contact pin 31 and the second contact pin 35 are compressed in the length direction, each contact pin 31, 35 returns to its position before being compressed relative to the spring 33.

[0073] In this embodiment, a pair of contact pins 31 and 35 have the same shape and can be connected in directions that intersect each other. Alternatively, they can be configured to have different shapes and connected by a spring between them.

[0074] Hereinafter, the pair of contact needles are referred to as the first contact needle 31 and the second contact needle 35. In this embodiment, the pair of contact needles 31 and 35 have the same shape. Therefore, the structure of the contact needle will be described with reference to the first contact needle 31.

[0075] The contact needle 31 may include a main body 312, a head 311, and a leg 313.

[0076] The main body 312 has a space S1 recessed in the longitudinal direction with a predetermined width and length at the center of each of its two sides. The lower end of the space S1 can form a stepped locking protrusion (not shown), and the upper end of the space S1 extends to the upper end of the head 311. The locking protrusion (not shown) refers to the structure in which the end of the leg 353 of the second contact pin 35 is locked when the second contact pin 35 is connected in a direction that intersects with the first contact pin 31.

[0077] The head 311 may be composed of a plate-shaped strip, which has the same length on both sides at the upper end of the main body 312 relative to the center of the main body 312, and has an upper tip 3110 formed along the upper front end. The plate-shaped strip may include a first strip section 311a and a second strip section 311b that are equidistant from the center portion 3111 of the main body 312.

[0078] That is, the head 311 can be configured such that the first strip section 311a and the second strip section 311b are respectively wound into a cylindrical shape with a diameter d3 in a semi-circular arc shape with reference to the central portion 3111. Furthermore, the width W1 of the standard central portion 3111 forming each strip winding preferably corresponds to the width of the space S1. This is because if the width W1 of the central portion 3111 is less than or greater than the width of the space S1, the defect rate of the stamping contact pin may increase.

[0079] Additionally, the head 311 can be formed into a cylindrical crown shape via the tip 3110. In this shape and construction of the head 311, the ball portion of the BGA is stably grounded and pressed against the test socket, thereby improving test accuracy.

[0080] In addition, the legs 313 can be formed by a pair extending symmetrically from the main body 312, and a predetermined space S2 is formed between the pair of legs, so that each leg can be guided when the first contact pin 31 and the second contact pin 35 are connected in a mutually intersecting direction.

[0081] In addition, when assembling the contact member 30, in order to facilitate the assembly of the second contact pin 35 in the direction intersecting with the first contact pin 31, an inclined surface 3120 can be formed on the portion of the pair of legs 313 extending from the main body 312.

[0082] More specifically, the leg portion 313 may include: a corner portion 3131, which may have a locking member formed at its end, wherein when the contact member 30 is compressed in the pressing direction, the locking member is located on the same plane as the tip portion 3110 and makes electrical contact with the terminal; a guide surface 3132 extending from the corner portion 3131 in a predetermined oblique direction and facing each other; and a bend portion 3133 forming a step from the guide surface 3132 toward the outside of the space S2.

[0083] In this structure, when each contact pin is assembled, the guide surface 3132 contacts and connects with the inclined surface 3120, so a pair of contact pins can be easily assembled. When each contact pin is assembled, the curved surface 3131 is locked in place by the locking protrusion (not shown), so that accidental separation of a pair of contact pins after connection can be prevented.

[0084] Figure 9 yes Figure 1 A schematic diagram of the manufacturing process of the hybrid test socket.

[0085] Below, refer to Figure 9 The manufacturing process of a hybrid test socket according to an embodiment of the present invention is described.

[0086] Reference Figure 9(a) The body of the test socket may have a hole h1 formed in an elastic insulator 13, which is hardened by jig operation or laser processing. The diameter d1 of the formed hole may be equal to or greater than the diameter d3 of the head of the contact pin.

[0087] Reference Figure 9 (b) and Figure 9 (c) After inserting the contact 30 into the hole h1, the film 51 of the laminated first member 50 is attached to the upper part of the first surface 11, so that the first member 50 can be disposed between the inner surface of the hole on the first surface 11 side and around one end of the contact 30.

[0088] More specifically, the film 51 can be hot-pressed so that the first member 50 can be well rolled into the space between the inner surface of the hole on the first surface 11 side and the periphery of one end of the contact member 30. The hot-compressed first member 50 can be disposed between at least a portion of the outer peripheral surface of the head 311 and the inner surface of the hole h1. Furthermore, when the first member 50 is compressed, the tip 3110 is exposed due to its shape, allowing it to penetrate the first member 50.

[0089] In this state, the first component 50 is hardened, as... Figure 9 As shown in (d), the manufacturing process of the hybrid test socket of the exemplary embodiment of the present invention is completed.

[0090] Figure 10 This is a schematic diagram of a hybrid test socket according to another embodiment of the present invention. Figure 11 yes Figure 10 A schematic diagram of the contact needle.

[0091] under, Figure 10 and Figure 11 Showing applications and Figures 1 to 9 A mixed test socket with different types of contacts is described, and the main differences from the embodiments described above are explained.

[0092] In this embodiment, the contact 70 used in the hybrid test socket is a contact pin 71 that is rolled up in a plate-shaped stamping process. The contact pin 71 is formed in a shape similar to a spiral compression spring, and its end can be formed into a crown shape by multiple tips 711.

[0093] With this shape and structure, the contact 70 of this embodiment can perform the function of a spring acting on the spring contact pin through the contact pin 71.

[0094] Furthermore, as the sheet is wound and formed, a space can be formed inside the contact 70, and this space can be filled with an elastic member 73 containing conductive particles. More specifically, the elastic member 73 can be formed by filling and hardening silicone containing metallic conductive particles between the contact pin 71 and the hole.

[0095] Additionally, the first member 50 may be disposed between the end of the contact member 70, including the tip 711, and the hole. For this structure, the first member 50 may be hot-pressed onto the first surface 11 as described above.

[0096] However, since the contact 70 in this embodiment is in a state where the interior is filled with an elastic member 73 containing conductive particles, it is necessary to arrange the conductive particles by magnetism to improve the electrical contact capability of the contact 70.

[0097] Therefore, in order to simplify the manufacturing process and make it easy to roll up and position the first component 50 between the end of the contact 70 and the hole, a magnetic force is applied to the elastic component 73 while the first component 50 is being bonded, thereby arranging the conductive particles. That is, the process of thermally compressing the film and the process of applying magnetism to the conductive particles can be performed simultaneously.

[0098] Although various embodiments of the present invention have been described in detail above, those skilled in the art will understand that various modifications can be made to the above embodiments without departing from the scope of the invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the scope of the appended claims, but also by their equivalents.

Claims

1. A hybrid test socket, comprising: Comprising: a body formed with a hole penetrating a first surface facing a terminal of a semiconductor device and a second surface facing a pad of a test device; a contact piece inserted into the hole, one end of which is in contact with the terminal of the semiconductor device and the other end of which is in contact with the pad of the test device, and which has elasticity in a pressing direction; and a first member bonded to one end of the contact piece. The first member is also provided between an inner surface of the hole on the first surface side and around one end of the contact piece.

2. The hybrid test socket of claim 1, wherein, The body comprises:

3. The hybrid test socket of claim 2, wherein, a base forming an outer shape of a test socket; and an elastic insulator filled in an inside of the base and hardened to form elasticity, the hole is formed penetrating the elastic insulator. The contact piece comprises:

4. The hybrid test socket of claim 3, wherein, a pair of contact pins; and a spring coupled between the pair of contact pins for providing elasticity. The pair of contact pins have the same shape and are coupled in directions crossing each other.

5. The hybrid test socket of claim 4, wherein, The contact pin comprises:

6. The hybrid test socket of claim 5, wherein, a body portion forming a predetermined width and thickness; a head portion formed at one end of the body portion and in contact with an inspection object; and a leg portion extending in a length direction of the body portion in a direction opposite to the head portion. The head portion is formed by a plate-like strip being wound integrally with the body portion.

7. The hybrid test socket of claim 6, wherein, The head portion is formed with a plurality of tip portions at an upper end thereof.

8. The hybrid test socket of claim 7, wherein, The first member is provided between at least a part of an outer peripheral surface of the head portion and an inner surface of the hole.

9. The hybrid test socket of claim 8, wherein, The second surface is formed with a stepped hole so that a step is formed toward the first surface.

10. The hybrid test socket of claim 3, wherein, A diameter of the stepped hole is larger than a diameter of the hole.

11. The hybrid test socket of claim 10, wherein, The first member is bonded in a state of being provided to a surface of one end of the contact piece, is wound into around one end of the contact piece and the hole, and is hardened.

12. The hybrid test socket of claim 2, wherein, The contact piece comprises:

13. The hybrid test socket of claim 3, wherein, a contact pin; and an elastic member including electrically conductive particles filled between the contact pin and the hole. The contact pin is a plate-like strip wound.

14. The hybrid test socket of claim 13, wherein, The electrically conductive particles are aligned by applying a magnetic force to the elastic member while the first member is bonded.

15. The hybrid test socket of claim 13, wherein, The contact pin is a plate-like strip wound. The electrically conductive particles are aligned by applying a magnetic force to the elastic member while the first member is bonded.