Reballing of BGAs is a very effective method to fix several problems with these semiconductors. For example, if you are experiencing the screen going black, you likely have bad solder joints. You may also be experiencing horizontal or vertical dots on the screen, which is also a sign of bad solder joints. BGA reballing can resolve these issues. Read on to find out why you should consider BGA reballing to remedy if you are broken or torn PCB.
Solder spheres
Reballing is the process of replacing solder spheres on BGA packages. You can perform the process with a beginning repair technician. It does not require customized fixtures or frames. It also eliminates the need to prepare devices for reballing. We can clean the finished product with alcohol after soldering. There are several factors to consider when reballing your BGA components.
The reballing process involves three steps, starting with the deballing step, followed by the placement of solder spheres. Then, the process involves using a robotic solder dip system, which utilizes a gentle and controlled multi-unit process to dissolve the solder spheres. The automated process eliminates the need for solder wicks, which may harm the pads.
A BGA package has numerous pins and is difficult to solder, resulting in poor performance and unreliable connections. Reballing balls on the BGA grid often mitigate the problem of loosening connections. In addition, solder spheres on the BGA package help to connect two packages. A BGA reballing process is an exact process that requires accurate control.
Thermal cycling
We can minimize the effect of thermal cycling on the reliability of BGA solder joints by proper control of the rework process. For example, one can perform the rework process using multiple daisy chains of solder balls, which result in a solitary resistance value for all the chains. We conduct thermal cycling using a data logger (the Agilent 34970A) populated with 34908A multiplexer cards that are singe-ended. The temperature cycles happen in intervals of 1 minute on a PCB assembly sample.
A coreless BGA package moved from a printed circuit board to determine the CTE. In addition, we subject it to DIC. The results showed that the CTE of the reballed BGA packages decreased significantly throughout temperature cycling. The thermal cycling test happened at 70°C and 110°C.
Electrical testing
There are two types of BGA reballing. One is mechanical, which requires destructive methods to inspect solder joints and determine if they can withstand stress. The other is electrical, which involves running a current through the BGA after being mounted on the PCB. Unfortunately, while electrical testing can help pinpoint any electrical problems, it cannot locate physical defects on the BGA. Hence, if you’re considering BGA reballing for your next electronic component, it’s essential to use a combination of both processes.
The mechanical test is crucial to determine whether the process was successful. Mechanical stress can cause fractures in the solder and NI/intermetallic interface. Therefore, it is essential to ensure that the process is thorough and controlled to reduce the risk of defects. To avoid this problem, it is vital to use the latest testing techniques to ensure a quality product. Here’s how. A good BGA reballing technique includes electrical testing of the reflow process.
The electrical test also evaluates the solder joint integrity. The density of the solder ball and the stiffness of the built-in PCB will determine the strength of the solder joint. The BGA device shall withstand a specified shear force based on the total number of solder balls. The electrical testing of BGA reballing requires advanced knowledge of electronic components and testing techniques. If your board is not ready for the reballing process, you should consider outsourcing the work to Rayming PCB & Assembly.
Solder bridges
During the reballing process, two solder depots can interfuse, resulting in a bridge. These bridges are not visible on the surface and can only be detected using X-ray inspection. Once detected, you must repair them by removing the component and reinstalling it. However, there are a few ways to reduce the risk of solder bridges during BGA reballing.
One of the most common causes of solder bridging is frowning, in which we compress the ball edges so much that they meet each other during the reflow. Using precision spacer blocks can help you avoid this by maintaining minimum standoff heights. You can also consult the Alpha TrueHeight Spacer Block product guide to learn how these spacers can help you eliminate solder bridging from BGA devices.
Another method for inspecting solder joints is using endoscopes. This tool was originally developed for medical applications and is an excellent tool for inspecting tiny objects inside a confined area. It has high magnification and often comes with visualization software, allowing technicians to view both the outer row of connections and the interior row with good lighting. As a result, they can determine the overall quality of a solder joint and whether the solder joint has a proper reflow.
SolderQuik(r)
The patented SolderQuik(r) for Ball Grid Array (BGA) reballing process came from Raychem Corporation in 1994. This method is a top SMT product of the year for its ease of use, low cost, and high reliability. This process is the preferred method of reballing BGAs and other devices. To ensure proper BGA reballing, a high-speed, low-cost reballing machine is essential.
To ensure optimal results, the SolderQuik(r) Reballing Starter Kit is an excellent choice for low-volume BGA reballing. It contains many items needed for successful reballing and perfectly fits your current processing environment. The Starter Kit is compatible with most BGA reballing stations and reflow systems. It can process multiple parts at a time and is compatible with most reflow systems.
PSI
When it comes to repairing, few things can beat the PSI of BGA reballing services. They have 20 years of experience in this field and consistently deliver top-quality rework at competitive prices. In addition, their highly-trained staff has more than 50 years of combined experience in array device reworking. Their specialized equipment allows them to quickly and accurately profile array assemblies up to 24″ x 0.25″ thick. In addition, their experienced technicians are experts in restoring gull-wing leads for QFP and SOIC devices.
To ensure that the parts produced by PSI are of the highest quality, they perform quality inspections before and after the reballing process. Several Tier 1 defense suppliers approve this process. The reballing process includes optical inspection, incoming and outgoing quality inspections, cleaning, and optional part marking. Manufacturers don’t have to stockpile lead because the process is completely customized for each component.
QCG
The EZReball(tm) reballing process allows a beginning repair technician to replace solder balls directly on the BGA package. A laser cuts the EZReball preforms for a clean, quick, and easy reballing process. In addition, EZReball(tm) performs we can reuse it repeatedly because the adhesive keeps the balls in place until the reflow process is complete.
Before reballing your BGA chips, you’ll need to have them prepared. You’ll need a holding stand, a stencil made of high-quality steel, and a QCG reballing iron. You’ll also need a hot air gun or BGA machine to heat the stencil. The entire process is fast and easy. Here’s how it works:
First, the reballing process removes the old ball solder joints from the BGA chips. Usually, a video graphic chip is the culprit of this process. If the chip is not performing well, it is a sign that the balls have separated by reballing them on the BGA grid. A QCG reballing process ensures that the components meet IPC and JEDEC requirements.
