BGA socket and assembling method thereof

Abstract

The invention discloses a BGA socket and an assembling method thereof, a conductive adhesive film is used as a conductive medium between a solder ball and a probe, conductive adhesive particles in the conductive adhesive film, the probe and the solder ball coincide in a one-to-one correspondence manner to ensure the reliability of electric connection between the solder ball and the probe, and meanwhile, the conductive adhesive film can provide a certain supporting and protecting effect. The solder balls are prevented from being damaged, and the reliability and the service life of the socket are improved; and meanwhile, the conductive adhesive film is embedded in the groove formed in the base in the BGA socket, so that the conductive adhesive film is favorably fixed, the conductive adhesive film is prevented from moving or falling off in the use process, and the stability of the whole structure is enhanced.

Description

Technical Field

[0001] The invention relates to the technical field of BGA packaging, and in particular to a BGA socket and an assembling method thereof. Background Art

[0002] BGA socket, or Ball Grid Array socket, is a key component used in the field of electronic engineering for integrated circuit packaging. BGA sockets are designed to mount packaged boards that use a grid of solder balls, known as BGA. Unlike the pin grid array (PGA) type, BGA packaged boards are usually mounted by direct soldering, while BGA sockets allow these boards to be mounted without soldering, allowing for easy removal. It is widely used in computer motherboards, network equipment, consumer electronics, industrial applications and other fields.

[0003] Some BGA circuits are generally customized non-standard products. Compared with traditional plastic-encapsulated BGA circuits, the coplanarity of their ball arrays is relatively low. When using traditional probe structure sockets for testing, in order to ensure the contact stability between the ball array and the probe, sufficient pressure must be loaded on the top surface of the circuit, which will cause solder ball damage and affect the reliability of the circuit.

[0004] The conductive adhesive technology that has emerged in recent years can effectively avoid the damage problem of ball grid arrays, and the conductive adhesive film plays a key role. Its upper surface contacts the circuit solder balls and forms effective protection, and the lower surface is connected to the test PCB board. However, there is a problem of poor contact between the conductive adhesive film and the test PCB board. Therefore, the conductive adhesive technology cannot be directly transplanted and used in the testing of military BGA type circuits. Summary of the invention

[0005] The object of the present invention is to provide a BGA socket and an assembly method thereof, so as to overcome the problem of poor contact between the conductive adhesive film and the test PCB board in the existing structure.

[0006] In order to solve the above problems, the present invention adopts the following technical solutions: A BGA socket comprises a BGA type circuit and a probe, a solder ball is arranged at the bottom of the BGA type circuit, a conductive adhesive film is arranged between the solder ball and the probe, conductive adhesive particles are arranged in the conductive adhesive film, and the conductive adhesive particles, the probe and the solder ball correspond to each other one by one.

[0007] Furthermore, the conductive film substrate is flexible silicone rubber.

[0008] Furthermore, the bottom of the probe is installed on the needle plate.

[0009] Furthermore, a test PCB board is arranged below the needle board, and the needle board is fixed at the center of the test PCB board.

[0010] Furthermore, a pressure applying mechanism is also provided on the top of the BGA type circuit.

[0011] Furthermore, the pressure applying mechanism includes a knob, a stroke nut, an upper and lower frame and a stroke pressure block, the knob is mounted on the stroke nut, and the lower part of the stroke nut is connected to the upper and lower frame and the stroke pressure block.

[0012] Furthermore, the BGA socket also includes a base, which is fixed on the test PCB board, and a groove is formed on the base, and the conductive adhesive film is arranged in the groove.

[0013] Furthermore, a through hole for the probe to pass through is opened in the center of the base.

[0014] Furthermore, the conductive adhesive film has the same size as the groove, and the conductive adhesive film is embedded in the groove.

[0015] In a second aspect, a method for assembling a BGA socket is provided, comprising the following steps: The conductive adhesive film is arranged between the solder ball and the probe, the solder ball contacts the upper end surface of the conductive adhesive film, and the probe contacts the lower end surface of the conductive adhesive film; A certain pressure is applied to make the solder ball achieve flexible contact with the silicone rubber substrate surrounding the conductive particles, ensuring a one-to-one correspondence between the conductive particles, the probe and the solder ball.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects: The present invention provides a BGA socket and describes the core features of the BGA socket, namely, using a conductive adhesive film as a conductive medium between a solder ball and a probe, wherein the conductive adhesive particles in the conductive adhesive film, the probe and the solder ball overlap one by one, and this structure can ensure good conductivity between the solder ball and the probe, and at the same time, the conductive adhesive film can provide a certain supporting and protective effect to prevent the solder ball from being damaged. In a traditional BGA socket, a conductive adhesive film is added between the solder ball and the probe, so that the BGA socket has the function of solder ball protection, thereby improving the reliability and service life of the socket.

[0017] Preferably, the connection between the pin board and the test PCB board enhances the stability and conductivity of the entire structure, making the test process more reliable.

[0018] Preferably, the BGA socket also includes a base, on which a groove for installing the conductive film is formed, the size of the groove is the same as the size of the conductive film, and the conductive film is embedded in the groove of the base, which helps to fix the conductive film and prevent it from moving or falling off during use.

[0019] The present invention also provides a method for assembling a BGA socket. The method applies a certain pressure to enable the solder ball to achieve flexible contact with the silicone rubber substrate around the conductive glue particles, thereby ensuring a one-to-one correspondence between the conductive glue particles, the probe and the solder ball. The method is simple and effective and can ensure the conductive performance and reliability of the BGA socket. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of a BGA socket structure; Figure 2 This is a structural diagram of the inner cavity of the base of the BGA socket; Figure 3 is a side view of the conductive adhesive film; Figure 4 A top view of the conductive adhesive film.

[0021] Among them, 1. Knob; 2. Travel nut; 3. Upper and lower frames and travel pressure block; 4. BGA type circuit; 5. Conductive adhesive film; 6. Probe; 7. Base; 8. Needle plate; 9. Side view PCB board; 10. Conductive adhesive particles. DETAILED DESCRIPTION

[0022] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail in the following specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0023] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0024] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0026] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0027] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0028] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] The present invention is further described in detail below in conjunction with the accompanying drawings: The present invention also provides a BGA socket, such as Figure 1 As shown, the BGA socket is provided with a conductive adhesive film 5 between the solder ball and the probe 6, the upper surface of the conductive adhesive film 5 contacts the solder ball, and the lower surface of the conductive adhesive film 5 contacts the probe 6. The conductive adhesive particles 10 in the conductive adhesive film 5, the probe 6 and the solder ball correspond one to one, so as to realize flexible contact between the solder ball and the probe 6, and effectively avoid the problem of solder ball damage. In actual situations, the conductive film 5 is subjected to pressure, so that the contact between the circuit solder ball and the upper surface of the conductive film 5 and the contact between the socket probe 6 and the lower surface of the conductive film 5 is closer, which can ensure good signal stability.

[0030] The solder ball is arranged on the upper side of the conductive film 5 and contacts the conductive film 5 . The lower side of the conductive film 5 contacts a probe 6 . The bottom of the probe 6 is mounted on a needle board 8 . The needle board 8 is connected to a test PCB 9 .

[0031] The pin board 8 generally includes a plurality of conductive channels or pins, which are used to connect the probe 6 to the pads on the test PCB board 9 , that is, the probe 6 is connected to the test PCB board 9 through the pin board 8 .

[0032] As an implementation mode of the present invention, the BGA socket further includes a base 7, which is mounted and fixed on the test PCB board 9, and a through hole for the probe 6 to pass through is opened at the center of the base 7; in addition, a groove is also opened at the center of the base 7 on one side facing the conductive film 5, and the conductive film 5 is embedded in the groove of the base 7. Correspondingly, Figure 2 , Figure 4 As shown, the conductive film 5 has a width dimension A 2 Equal to the base 5 groove width dimension A 1 , conductive film 5 length dimension B 2 Equal to the base groove length dimension B 1 .

[0033] The base 7 is designed to be a sturdy and easy-to-install structure, including features such as positioning holes or fixing grooves to facilitate connection and fixing with the test PCB board 9.

[0034] Specifically, the BGA socket further includes a knob 1, a travel nut 2, upper and lower frames, a travel pressing block 3, and a BGA type circuit 4, wherein the BGA circuit adopts surface mounting technology, wherein the pins of the IC are arranged in a spherical form at the bottom of the package to form a grid-like pattern. These spherical pins are used to connect with the pads on the printed circuit board (PCB) to achieve circuit connection and signal transmission; the solder balls are arranged on the lower surface of the BGA type circuit 4, and the upper and lower frames and the travel pressing block 3 are arranged on the upper surface of the BGA type circuit 4, and the upper and lower frames and the travel pressing block 3 are arranged on the upper end surfaces. The travel nut 2 is installed on the travel nut 2.

[0035] In another embodiment of the present invention, a solder ball protection type BGA test socket based on conductive adhesive connection is designed, and its structure includes a test socket and a conductive adhesive film. The test socket structure mainly includes a knob 1, a travel nut 2, an upper and lower frame and a travel block 3, a BGA type circuit 4, a conductive adhesive film 5, a probe 6, a base 7 and a needle plate 8. The various components of the socket body are mainly connected by a combination of bolts and nuts; The conductive adhesive film 5 is a filler-added acrylic adhesive, in which conductive particles (such as silver-plated nickel particles or silver-plated glass beads) are distributed to make it conductive. Its main components include a mixture of acrylic ester and epoxy resin, and it has good conductivity, insulation, corrosion resistance and plasticity; wherein, insulation means that in the horizontal direction, the conductive adhesive film has an insulating property that can prevent current from flowing in an unnecessary path; good conductivity means that due to the presence of the conductive adhesive particles 10 in the conductive adhesive film 5, the conductive adhesive film 5 can tightly connect electronic components such as circuit boards and chips together under a certain temperature and pressure to form a stable circuit system.

[0036] The main components of the conductive adhesive particles 10 include a silicone matrix and a conductive filler. The silicone matrix provides good flexibility and elasticity, while the conductive filler determines the conductive properties of the conductive adhesive particles, which have the characteristics of flexibility, conductivity and weldability.

[0037] According to the overall size of the BGA circuit, the width of the groove of the test socket base 7 is A 1 , length B 1 The conductive film 5 is embedded in the groove of the base 7, and the width of the conductive film 5 is A. 2 Equal to the base 5 groove width dimension A 1 , conductive film 5 length dimension B 2 Equal to the base 5 groove length dimension B 1 ; The conductive film 5 substrate is made of flexible silicone rubber with a thickness of 0.8mm≤H≤1.0mm and a width of A. 2 , length B 2 ; Conductive adhesive particles 10 are doped in specific areas of the conductive adhesive film 5 according to the size and spacing of the solder balls of the BGA type circuit 4; The conductive film 5 is embedded in the groove of the socket base 7, and the socket probe 6 overlaps with the conductive particles on the conductive film 5 one by one to form an effective connection; the BGA type circuit 4 is placed on the conductive film, and the solder balls overlap with the conductive particles on the conductive film 5 one by one to form an effective connection.

[0038] The present invention also provides a method for assembling a BGA socket, comprising the following steps: The conductive film 5 is arranged between the solder ball and the probe 6, the solder ball contacts the upper end surface of the conductive film 5, and the probe 6 contacts the lower end surface of the conductive film 5; A certain pressure is applied to make the solder balls come into flexible contact with the silicone rubber substrate surrounding the conductive adhesive particles 10, so as to ensure that the conductive adhesive particles 10, the probes 6 and the solder balls overlap one by one.

[0039] In detail, the conductive film 5 is embedded in the groove of the base 7, and its size is the same as that of the groove of the base 7. The probe 6 passes through the central through hole of the base 7 and contacts the conductive film 5. The BGA type circuit 4 is arranged above the conductive film 5, and the upper and lower frames and the stroke pressing block 3 are arranged on the upper end surface of the BGA type circuit 4, and pressure is applied through the stroke nut 2 and the knob 1 installed on the stroke nut 2.

[0040] Working principle: Close the socket cover and turn the knob 1 to apply a certain pressure to the top surface of the BGA circuit 4. At this time, the conductive adhesive particles 10 collapse and deform after being squeezed by the solder balls, and the solder balls and the silicone rubber substrate around the conductive adhesive particles 10 achieve flexible contact, which can provide good protection for the solder balls. The BGA circuit 4 is subjected to pressure, so that the circuit solder balls and the upper surface of the conductive film 5, and the socket probes 6 and the lower surface of the conductive film 5 are in closer contact, thereby ensuring good signal stability.

[0041] According to the present invention, based on the traditional BGA test socket, only the customized conductive adhesive film 5 needs to be developed to perform the combined test, and there is no need to redesign the test socket, thus meeting the requirements of low design cost and short development cycle.

[0042] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A BGA socket, characterized in that: The BGA socket comprises a BGA type circuit (4) and a probe (6), a solder ball is arranged at the bottom of the BGA type circuit (4), a conductive adhesive film (5) is arranged between the solder ball and the probe (6), conductive adhesive particles (10) are arranged in the conductive adhesive film (5), and the conductive adhesive particles (10), the probe (6) and the solder ball are in one-to-one correspondence.

2. A BGA socket according to claim 1, characterized in that: The conductive adhesive film (5) substrate is flexible silicone rubber.

3. A BGA socket according to claim 1, characterized in that: The bottom of the probe (6) is mounted on the needle plate (8).

4. A BGA socket according to claim 3, characterized in that: A test PCB board (9) is arranged below the needle board (8), and the needle board (8) is fixed at the center of the test PCB board (9).

5. The BGA socket according to claim 1, characterized in that: A pressure applying mechanism is also provided at the top of the BGA type circuit (4).

6. A BGA socket according to claim 5, characterized in that: The pressure applying mechanism comprises a knob (1), a stroke nut (2), an upper and lower frame and a stroke pressing block (3); the knob (1) is mounted on the stroke nut (2), and the lower part of the stroke nut (2) is connected to the upper and lower frame and the stroke pressing block (3).

7. The BGA socket according to claim 1, characterized in that: The BGA socket further comprises a base (7), the base (7) being fixed on the test PCB board (9), the base (7) being provided with a groove, and the conductive adhesive film (5) being arranged in the groove.

8. A BGA socket according to claim 7, characterized in that: A through hole for the probe (6) to pass through is provided at the center of the base (7).

9. The BGA socket according to claim 7, characterized in that: The conductive adhesive film (5) has the same size as the groove, and the conductive adhesive film (5) is embedded in the groove.

10. An assembly method of a BGA socket according to claims 1-9, characterized in that: The following steps are involved: The conductive adhesive film (5) is arranged between the solder ball and the probe (6), the solder ball contacts the upper end surface of the conductive adhesive film (5), and the probe (6) contacts the lower end surface of the conductive adhesive film (5); A certain pressure is applied to enable the solder ball to achieve flexible contact with the silicone rubber substrate surrounding the conductive glue particles (10), thereby ensuring a one-to-one correspondence between the conductive glue particles (10), the probe (6) and the solder ball.

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