Universal Device for Ball Grid Array Device Planting

Abstract

The invention discloses a ball-planting device for a ball grid array device, which aims to provide a ball-planting device with strong practicability, flexible and convenient operation, and good versatility. The present invention is realized through the following technical scheme: the ball planting pool of the inner cavity frame of the ball planting table is equipped with a lifting support block that drives the ball grid array device substrate to rise / fall synchronously and a main clamping slider that slides along the chute on both sides of the length of the frame mouth, And the auxiliary clamping slider that slides along the wide-side suspension beam slide rail; the two main clamping sliders move horizontally synchronously toward or against each other through the horizontal relative linkage mechanism connected to the horizontal adjustment knob below it, and the two auxiliary clamping sliders also The slider moves vertically and synchronously in the opposite direction or backward direction through the longitudinal relative linkage mechanism connected to the longitudinal adjustment knob below it; the solder balls fall on the pin pads of the ball grid array device substrate through the leakage holes of the solder ball leakage net, and control the time of ball planting. The number of solder balls falling on the pin pads of the ball grid array device substrate through the leakage mesh holes realizes the solder ball skipping of the ball grid array devices with different solder ball numbers.

Description

technical field [0001] The invention relates to the technical field of electronic packaging, in particular to a ball planting device for ball grid array packaging devices. Background technique [0002] The ball grid array package (hereinafter referred to as BGA) makes an array of solder balls on the bottom of the package substrate as the I / O terminal of the circuit to interconnect with the printed circuit board PCB, which improves the placement yield and potentially reduces the cost; BGA packaged devices are in The bottom surface of the substrate is made of spherical contact pins in an array, which has the advantages of short pins, small lead inductance and capacitance; many pins, high ratio of the number of terminals to the size of the device package; large center-to-center spacing of solder joints, firm pins, and common Good surface performance and high assembly yield; the contact surface between the array solder ball and the substrate is large, which shortens the signal t...

AI Technical Summary

Problems solved by technology

A disadvantage of BGA packages is that the solder balls cannot stretch like long leads, so they do not have material stiffness in terms of material properties

All soldering devices, due to the difference in thermal expansion coefficient between the PCB substrate and the BGA package, bend (thermal stress), or extend and vibrate (mechanical stress), which may cause solder joints between the solder balls of the BGA device and the PCB substrate fracture

The main defect type is that the solder ball pitch exceeds the standard during the ball planting process, and then the ball pitch of the BGA device exceeds the standard, resulting in failure of the assembly and welding of the BGA device and the PCB board

[0003] At present, BGA devices have been widely used in many products, but in the application of multi-variety and small-batch products, the following two types of problems are more prominent in production: 1) The characteristics of multi-variety and small-batch products lead to the comparison of the quantity of single BGA devices purchased. Few, the method of ball placement is to manually place solder balls with tweezers or templates, which has low efficiency, high cost, and extremely high requirements for operators. The overall level is at the repair level of BGA components. BGA devices have pin oxidation, partial Defects such as missing solder balls

2) The design of the printed board warped due to heat, poor printing of solder paste, and insufficient soldering temperature lead to soldering defects such as short circuits or virtual soldering in BGA devices

As the demand for BGA continues to grow, and with the development of packaging technology, the types of BGA devices and the number of solder balls on the substrate are increasing, and the spacing is getting smaller and smaller. Manual ball planting by operators will eventually be unable to do this job.

Using scrapped original devices to replace new ones will greatly increase production costs on the one hand, and on the other hand, if some BGA devices are out of stock, they need to be re-purchased, and the BGA device procurement cycle is generally longer, which seriously delays production progress

[0004] 3) Automated BGA device ball planting equipment is expensive and is mainly used by BGA device manufacturers, while electronic assembly manufacturers for BGA device assembly and assembly will basically not purchase automated ball planting equipment due to production cost considerations. The ball planting method only uses Manual placement with tweezers or special ball planting templates, low ball planting efficiency, high cost, extremely high requirements for operators, and low ball planting yield

The four height adjustment screws are adjusted separately, and the height of the four-corner support slider may be uneven, resulting in uneven placement of the ball grid array and inconsistent distance between the device substrate surface and the solder ball drain plate

[0006] Although the ball-planting device in the prior art can realize the ball-planting and fixing of ball grid array devices of different specifications and models, it is necessary to make corresponding special solder ball bushings for different specifications and models of ball grid array devices, and the production cost is high, and the types of special solder ball bushings more, increasing the human resources for storage and management

Although the ball planting device is equipped with a solder ball pouring groove, which can realize solder ball recovery, but the solder ball pouring groove has no baffle switch. When the ball planting device is shaken to miss the solder balls, some solder balls are easy to overflow through the pouring groove , resulting in wasted solder balls and excess on the workbench

[0007] As the demand for BGA continues to grow, and with the development of packaging technology, the types of BGA devices and the number of solder balls on the substrate are increasing, and the spacing is getting smaller and smaller. Manual rework and ball planting by operators will eventually not be able to do this job.

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