Manual plate alignment BGA chip ball mounting jig

Abstract

The present disclosure relates to a manual whole board BGA chip ball mounting jig, comprising a chassis, a base frame, a core plate assembly and a steel mesh assembly; the core plate assembly is pressed on the upper end face of the base frame by the steel mesh assembly; the steel mesh assembly comprises an upper frame, a steel mesh and a lower frame plate; the lower end face of the steel mesh assembly is sealingly connected to the base frame; the middle part of the upper frame is hollowed out and separated to form several ball placing grooves; the steel mesh is pressed into the accommodating groove by the upper frame plate; and the separation structure of the upper frame presses the steel mesh assembly at multiple points. The ball mounting jig bridges the steel mesh on the base frame by the lower frame, and the steel mesh is supported by the lower frame and the core plate disc; the coplanarity of the steel mesh and the whole board chip ball mounting is ensured by the upper frame separation structure, which can improve the ball mounting efficiency, reduce the missing mounting rate, build two-stage sealing of the jig, effectively prevent vacuum leakage, ensure the negative pressure ball mounting suction force, and improve the ball mounting success rate. By replacing the core plate and the steel mesh assembly, the whole board BGA chip variety can be quickly replaced, and more types of whole board BGA ball mounting can be provided.

Description

Technical Field

[0001] This disclosure relates to the field of chip fabrication technology, and more specifically, to a manual BGA chip ball-planting fixture. Background Technology

[0002] Ball placement, or ball grid array (BGA) packaging technology, is a process that requires ball placement after chip fabrication and often necessitates mass production. Currently, BGA chip ball placement primarily involves precisely placing solder balls onto the BGA chip's pads. To prevent excess balls, the ball placement holes are sized to match the solder balls, allowing them to be precisely implanted onto the chip directly below when vacuum forces are applied.

[0003] Existing ball-planting fixtures are generally of a stacked structure, precisely stacking core boards and stencils in a vacuum zone. The stencils are supported by the core boards. Therefore, the sealing reliability between the two affects the effective vacuum between the stencils and the core boards. In addition, in order to increase the number of balls planted at one time, the ball-planting area of ​​the fixture is usually large. Under the action of vacuum suction, the large-area stencil is prone to deformation, and the uniformity of the distance between the stencil and the chip surface is insufficient. This results in the coplanarity of the chip after ball planting not meeting the standard, or even poor ball planting or failure.

[0004] In view of this, this design proposes a manual whole-board BGA chip ball-planting fixture, which provides secondary sealing of the core board by supporting the stencil assembly through a bridge and preventing deformation of the stencil assembly and vacuum leakage in the ball-planting area.

[0005] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Utility Model Content

[0006] The purpose of this disclosure is to provide a manual BGA chip ball-mounting fixture, thereby overcoming, at least to some extent, one or more problems caused by the limitations and defects of related technologies.

[0007] According to one aspect of this disclosure, a manual BGA chip ball-planting fixture is provided, including a base frame, a base frame, a core board assembly, and a stencil assembly; wherein, a vacuum groove is formed on the upper end face of the base frame, the vacuum groove is connected to a vacuum pump through a pipe, the base frame is located on the upper end face of the base frame and surrounds the vacuum groove, and the stencil assembly is mounted on the base frame; the core board assembly is pressed onto the upper end face of the base frame by the stencil assembly;

[0008] The steel mesh assembly includes an upper frame, a steel mesh, and a lower frame plate. The lower end face of the upper frame is sealed to the base frame, forming a vacuum zone between the two and the vacuum tank. The core plate assembly is located within the vacuum zone. The upper surface of the upper frame is hollowed out in the middle, and multiple partition structures are set to divide the hollowed-out area into several ball-placement grooves. A receiving groove is set inside the upper frame, and the steel mesh is attached to the bottom of the receiving groove and its end edge is pressed by the lower frame plate. The middle part of the steel mesh is connected to the partition structure at several points for multi-point flattening of the middle part of the steel mesh assembly. The upper surface of the steel mesh forms the bottom of the ball-placement groove and has several ball-planting holes. The core plate assembly is stacked under the steel mesh and provides support.

[0009] In one exemplary embodiment of this disclosure, the core board assembly includes a core board and a core board tray. The core board tray is sealed to the upper frame opening of the base frame and has a core board groove for embedding the core board. The bottom of the core board groove has a plurality of vacuum holes distributed in a dot matrix. The two ends of the core board tray are provided with core board pick-up and drop slots extending to the core board groove.

[0010] In one exemplary embodiment of this disclosure, a plurality of core plate positioning pins and frame positioning pins are provided on the base frame. The core plate positioning pins are arranged in pairs on different frame edges or corners of the base frame for mounting the core plate. Similarly, the core plate positioning pins are arranged in pairs on different frame edges or corners of the base frame for mounting the upper frame.

[0011] In one exemplary embodiment of this disclosure, at least two elastic telescopic positioning pins are provided on the base frame. The elastic telescopic positioning pins are arranged in pairs, staggered or diagonally, and are in a vertical and vertically telescopic state. A first positioning hole is provided on the steel mesh, a middle hole is provided on the core plate, and a second positioning hole is provided on the core plate. The elastic telescopic positioning pin passes through the middle hole and is connected in series with the first positioning hole and the second positioning hole to jointly position the steel mesh and the core plate.

[0012] In one exemplary embodiment of this disclosure, a plurality of chip slots are formed on the chip board, and a vacuum channel is provided in the chip slots.

[0013] An exemplary embodiment of this disclosure provides a manual BGA chip ball-planting fixture, which uses an upper frame to bridge a steel mesh on a base frame. Unlike the existing steel mesh layer support, the steel mesh is supported by a lower frame and a core plate. The middle of the steel mesh is flattened at multiple points through a partition structure. At the same time, multiple ball-planting grooves are constructed on the surface of the steel mesh to divide the large area of ​​ball planting into multiple small area partitions for ball planting. This can improve ball planting efficiency, reduce the probability of missed planting, improve the rigidity and strength of the steel mesh support, and ensure the uniformity of the ball planting gaps and the coplanarity of the solid balls.

[0014] The core board assembly is located inside the upper frame. The upper frame is connected to the base frame to form an outer seal, and the core board assembly is bonded to the lower frame to form an interlayer seal. Thus, the fixture effectively prevents vacuum leakage by constructing a two-stage seal, ensuring the suction force of negative pressure ball planting and improving the success rate of ball planting.

[0015] The chips are centrally mounted on the core board. By replacing the core board, stencil, and stencil frame, other types of full-board BGA chips can be quickly replaced, providing more options for full-board BGA ball placement. The fixture has high applicability and reduces the total cost of fixture investment.

[0016] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0017] The above and other features and advantages of this disclosure will become more apparent from the detailed description of exemplary embodiments thereof with reference to the accompanying drawings.

[0018] Figure 1 The front view of the ball-planting fixture is shown.

[0019] Figure 2 A three-dimensional view of the ball-planting fixture is shown.

[0020] Figure 3 An exploded view of the components of the ball-planting fixture is shown.

[0021] Figure 4 A cross-sectional view of the ball-planting fixture is shown.

[0022] Figure 5 An exploded view of the steel mesh assembly is shown.

[0023] Figure 6 A cross-sectional view of the core board assembly is shown.

[0024] Figure 7 A partial structural diagram of the core board is shown.

[0025] Attached image labels:

[0026] 1. Vacuum pump; 11. Control valve; 2. Base frame; 21. Vacuum tank; 22. Clearance hole; 3. Base frame; 31. Core plate loading / unloading slot; 32. Core plate positioning pin; 33. Frame positioning pin; 34. Core board loading / unloading slot; 4. Steel mesh assembly; 41. Upper frame; 411. Ball placement slot; 42. Steel mesh; 421. Ball planting hole; 422. Vacuum ball planting area; 43. Lower frame plate; 44. First positioning hole; 6. Elastic telescopic positioning pin; 7. Core board assembly; 71. Core board; 711. Chip slot; 712. Second positioning hole; 713. Vacuum channel; 72. Core board plate; 721. Core board slot; 722. Vacuum hole; 723. Board loading slot; 724. Intermediate hole. Detailed Implementation

[0027] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted.

[0028] This example embodiment provides a manual BGA chip ball-mounting fixture, such as... Figures 1-7 As shown, it includes a base frame 2, a base frame 3, a core board assembly 7, and a steel mesh assembly 4;

[0029] The base frame 2 is equipped with a platform and adjustable horizontal support legs. A vacuum groove 21 is opened on the upper surface of the platform, and a pipe joint is set at the bottom. The vacuum pump 1 is independently supported on the ground and is connected to the vacuum groove 21 through pipes and joints. A control valve 11 is set on the pipe. The base frame 2 and the base frame 3 can be an integral structure. In order to facilitate positioning, adjustment and processing, this embodiment adopts a split structure. The base frame 3 is detachably installed on the platform of the base frame 2 by screws and surrounds the vacuum groove 21.

[0030] like Figure 5 As shown, the steel mesh assembly 4 includes an upper frame 41, a steel mesh 42, and a lower frame plate 43. To ensure the rigidity of the steel mesh 42, the upper surface of the upper frame 41 is hollowed out in the middle, and multiple partition structures are set to divide the hollowed-out area into several ball-holding grooves 411. The upper frame 41 is provided with a receiving groove (not shown in the figure). The steel mesh 42 and the core plate assembly are stacked and installed in the receiving groove, and the end edges are pressed by the lower frame plate 43. The middle part of the steel mesh 42 is connected to the partition structure by several screws, which flatten and support the middle part of the steel mesh assembly 4 at multiple points, thereby improving the rigidity of the steel mesh 42.

[0031] The stencil 42 is laid at the bottom of the ball placement groove 411, and several ball placement holes 421 are machined on its upper half. The stencil 42 and the core board assembly 7 are both installed on the base frame 3 and positioned by the positioning component on it, so that the ball placement holes 421 are precisely aligned with the ball placement points of the chip. The solder balls in the ball placement groove 411 are precisely inserted into the chip directly below through the ball placement holes 421.

[0032] The core board assembly 7 is embedded in the receiving groove and located in the vacuum area enclosed by the upper frame 41 and the vacuum groove 21. The inner edges of both sides of the upper plane of the base frame 3 are provided with core plate picking and placing grooves 31. The opening of the core plate picking and placing grooves 31 extends from the inner edge of the base frame 3 to a certain width outside the outer edge of the core board assembly 7 so that fingers can be inserted to pick and place the core board assembly 7.

[0033] Understandably, the upper frame 41 is mounted on the base frame 3, and the lower frame plate 43 is attached to the core plate assembly 7, sealing and pressing the upper plane edge of the core plate assembly 7 to achieve a first-level seal in the vacuum ball-planting area. The upper frame 41 is attached to and pressed against the end face of the base frame 3 to achieve a second-level seal. Both of the above-mentioned seals can be enhanced by using a structure with a sealing gasket or a sealing strip.

[0034] In one exemplary embodiment of this disclosure, such as Figure 6 As shown, the core board assembly 7 includes a core board 71 and a core board disk 72. The core board disk 72 has a plurality of vacuum holes 722 evenly distributed in a dot matrix to evenly distribute the vacuum suction force. It covers the frame opening of the base frame 3. The core board disk 72 is provided with a core board groove 721. Both ends of the core board disk 72 are provided with core board pick-up and drop slots 723 extending from the end edge to the core board groove 721. The core board 71 is embedded in the core board groove 721 and can be easily picked up and dropped by the core board pick-up and drop slots 723.

[0035] like Figure 4 As shown, the core plate 71 and the core plate disk 72 divide the vacuum area from bottom to top to form a convergence area, a vacuum distribution area and a vacuum ball planting area 422.

[0036] In one exemplary embodiment of this disclosure, the upper surface of the base frame 3 is provided with a core plate positioning pin and a frame positioning pin 33. There are at least two core plate positioning pins and two frame positioning pins 33. The core plate positioning pins 32 are arranged in pairs on two different frame edges or two opposite frame corners of the base frame 3 for quick insertion and connection of the core plate plate 72. Similarly, the core plate positioning pins 32 are arranged in pairs on two other different frame edges or two other opposite frame corners of the base frame 3 for quick insertion and connection of the upper frame 41.

[0037] Furthermore, to facilitate quick and precise alignment of the ball-planting holes 421 of the stencil 42 with the ball-planting points of the chip, at least two elastic telescopic positioning pins 6 are provided on the base frame 3, such as... Figure 3 As shown in the figure, this embodiment illustrates the arrangement of two elastic telescopic positioning pins 6, which can be arranged in pairs, staggered or diagonally on the frame edge or corner of the base frame 3. The elastic telescopic positioning pin 6 is equipped with a spring, which is elastically vertically supported by the spring and installed in the step mounting hole of the base frame 3, and can be vertically elastically sliding and telescopic. The elastic telescopic positioning pin 6 can position and connect the steel mesh 42 and the core plate 71. A first positioning hole 44 is opened at the corresponding position on the steel mesh 42, and a second positioning hole 712 is opened on the core plate 71. At the same time, a middle hole 724 for clearance is opened on the core plate. After the elastic telescopic positioning pin 6 passes through the middle hole 724, it can position the steel mesh 42 and the core plate 71 relative to each other by sequentially connecting the first positioning hole 44 and the second positioning hole 712.

[0038] In addition, in order to allow the elastic telescopic positioning pin 6 to extend and retract, a clearance hole 22 is provided on the upper end face of the base frame 2.

[0039] In one exemplary embodiment of this disclosure, the chip is embedded in chip slot 711, such as Figure 7 As shown, multiple chip extraction slots are distributed along the end of the chip slot 711, and several vacuum channels 713 are evenly opened at the bottom of the slot, connecting the chip periphery to the vacuum ball-planting area 422.

[0040] The directional words "up," "down," "side," "end," "inside," and "outside" mentioned in this article are based on... Figures 1-7 The orientation or positional relationship shown in the corresponding figures refers to the orientation or positional relationship in the state of use or in motion. These terms are primarily used to better describe the invention and its embodiments and are not intended to limit the indicated device, element, or component to having a particular orientation or to be constructed and operated in a particular orientation.

[0041] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the utility models disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the claims.

[0042] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A manual BGA chip ball-planting fixture, characterized in that: The system includes a base frame, a base frame, a core board assembly, and a steel mesh assembly. The base frame has a vacuum groove on its upper surface, a pipe connected to a vacuum pump, and the base frame is located on the upper surface of the base frame and surrounds the vacuum groove. The steel mesh assembly is mounted on the base frame. The core board assembly is pressed against the upper surface of the base frame by the steel mesh assembly. The steel mesh assembly includes an upper frame, a steel mesh, and a lower frame plate. The lower end face of the upper frame is sealed to the base frame, forming a vacuum zone between the two and the vacuum groove. The core plate assembly is located within the vacuum zone. The upper surface of the upper frame is hollowed out in the middle, and multiple dividing structures are provided to divide the hollowed-out area into several ball-placement grooves. A receiving groove is provided inside the upper frame. The steel mesh is attached to the bottom of the receiving groove and its end edge is pressed down by the lower frame plate. The middle part of the steel mesh is connected to the dividing structure at several points for pressing the middle part of the steel mesh assembly flat at multiple points. The upper surface of the steel mesh forms the bottom of the ball-placement groove and has several ball-planting holes. The core plate assembly is stacked under the steel mesh and provides support.

2. The manual BGA chip ball-planting fixture as described in claim 1, characterized in that: The core board assembly includes a core board and a core board tray. The core board tray is sealed to the upper frame opening of the base frame and has a core board groove for embedding the core board. The bottom of the core board groove has a plurality of vacuum holes distributed in a dot matrix. The two ends of the core board tray are provided with core board loading and unloading slots extending to the core board groove.

3. The manual BGA chip ball-planting fixture as described in claim 2, characterized in that: The base frame is provided with a plurality of core plate positioning pins and frame positioning pins. The core plate positioning pins are arranged in pairs on different frame edges or frame corners of the base frame for installing the core plate. Similarly, the core plate positioning pins are arranged in pairs on different edges or corners of the base frame for mounting the upper frame.

4. The manual BGA chip ball-planting fixture as described in claim 2 or 3, characterized in that: At least two elastic telescopic positioning pins are provided on the base frame. The elastic telescopic positioning pins are arranged in pairs, staggered or diagonally, and are in a vertical and vertically telescopic state. A first positioning hole is opened on the steel mesh, a middle hole is opened on the core plate, and a second positioning hole is opened on the core plate. The elastic telescopic positioning pin passes through the middle hole and is connected in series with the first positioning hole and the second positioning hole to jointly position the steel mesh and the core plate.

5. The manual BGA chip ball-planting fixture as described in claim 4, characterized in that: The core board has several chip slots, and a vacuum channel is provided in each chip slot.

Images