BGA refers to Ball Grid Array. BGA is gaining popularity in the PCB sector for its high-density ability. As for BGA’s popularity, the BGA rework also comes to the point.
However, the BGA is part of Surface Mount Device (SMD) IC connections. The BGA technology makes the IC connection by reducing the density by connecting the under-side of the ICs packages.
As a result, the PCB layout becomes simple.
Despite the simpler end, the design process requires extensive technical knowledge and experience. Unusual events need removing or replacing PCB components.
These may require de-soldering, removal, and re-soldering. In this situation, SMD packages need BGA to rework service.
In the following entire post, we will discuss everything about BGA rework, BGA station, and other related things to the BGA rework process.
What Is A BGA Package?
Unlike other connection systems, BGA has a different approach for component connection on PCBs. Other connections like quad flat packs use the edge of the packages for PCB component connection.
On the other hand, the BGA package uses the underside of the package of the components.
As a result, there are more areas available in the BGA package component in SMD connection. Whereas, the pin connections have limited area.
By the way, in the BGA package, the pins are arranged in a grid pattern under the surface of the chip carrier. The name Ball grid Array comes from the pattern of the package.
The significance of the BGA connectivity is that it provides balls with solder pads instead of a pin connection. For the PCBs’ ICs, the Ball Grid Array connections are made especially with particular sizing.
The BGA package provides additional advantages aside from connectivity like lower thermal resistance. This ensures quick release of heat from the internal side of the integrated circuit.
So, the ICs can withstand more heat aside from the need for an extra cooling system. Summing up everything, the BGA package offers more stable performance than other connection facilities.
The Objective And Rational Reasons To Use BGA Package
There are many objectives to using the BGA package. BGA is developed to ensure the following benefits in the connection system.
- To efficiently use the space on the PCBs which helps to no-left any space on PCB wasted.
- To improve the thermal management system, as well as the electrical performance of the PCBs and their components. If implemented successfully, the controlled impedance and low inductance will be acquired. So, there will not be any excessive heat on PCBs.
- To acquire great manufacturability. Because, if the BGA can be implemented perfectly, the soldering process will be more efficient. So, better solderability and more space will be facilitated.
- To lessen the thickness of the PCBs and PCB components. So, accuracy and more flexibility will be available for small electronics.
- To ensure the reliability of BGA reworks. Because, if something gets faulty, everything becomes complex to resolve the issues due to complex connectivity and assembly. BGA rework will be more reliable with BGA packages.
BGA Package Helps You To Use Space Efficiently
You may wonder why you should utilize BGA over other connection technologies. Because they have a few flaws The following arguments will help you utilize the BGA package rationally.
- Connectivity like quad flat pack has very thin pins. For a rational reason, they have chances to damage easily. Also, any inefficient management and handling can drive them to be displaced as well. BGA brings solutions to this issue.
- Along with thin pins, the pin density is huge on the other connection systems. This allows fewer spaces for the pins.
- Due to the dense pins, the soldering process could be very complex. Also, the efficiency will not get that much higher in soldering as well.
So, thinking about everything, the rational reason to use the BGA package is clear to the manufacturers.
What Is BGA Rework Station?
BGA rework station is a device that is used in repairing PCB in Surface Mount Devices with Ball Grid Array. The BGA rework station is also known as SMD and SMT rework station as well.
With the BGA rework station, the PCB technicians repair the PCBs. The repairing includes defected parts removing, new part installation, or replacing any part that is missing.
The most significant advantage of the BGA rework station is that it can also repair other connection PCBs. They include quad flat packages, column grid arrays, chip-scale packages, and so on.
BGA Rework Station
There are different features on different models of BGA rework stations. The different features are compatible with the different sizes of the PCBs, and types of the PCBs are to be done by the rework station.
As for your entry-level PCBs, you can go for the BGA rework station that does not have split-vision functionality availability.
On the other hand, for the advanced and more complex functionalities, the split-vision functionality enabled rework station is recommended.
However, depending on the functionality needed, the BGA rework station could be automated or manual.
The Working Steps of BGA Rework
The BGA rework process is completed in three major steps. However, there are maybe some sub-processes as well.
Let’s check how the BGA to rework process works with the rework station.
First Remove The Faulty Components
The first step of BGA rework is to remove the components to be altered or reworked. For removing the component in a safe state, you must pre-heat the printed circuit boards.
Before this, the components need to be clamped as well so that they could not be displaced due to heat.
So, you must monitor the proper heat state. The pre-heating eases the removal of components.
However, for proper heat monitoring, BGA infrared rework station will help you. You can do it manually by using a thermocouple, or IR BGA reworks station.
After removing the components, make sure you apply nitrogen in the heated area. This will remove the oxygen to ensure preventing oxidation.
BGA Steps Are Done In Several Steps
Now Clean The Area from Where Components Are Removed
Now you have removed the faulty components. After removing them, the immediate task is to clean the area you removed the components from.
However, let the area be cooled first. Now clean the area. Don’t allow any residue on the area. You will not face any complexity on the lead-enabled printed circuit boards to remove the residues.
But in the modern lead-free boards, you will face some challenges to clean the area.
The most crucial point of lead-free board cleaning is to control the temperature in an extensive and efficient way. Otherwise, you may face a damaging issue with the solder mask, the growth of metallic phases. You may also face the damage of neighboring components.
Keep the heat and airflow proportional for accurate cleaning. By the way, keep the cleaning site upward as well. Remember another thing. Finish the entire cleaning process in a single cycle to prevent the thermal stress of the PCB.
Now Place The New Solder Balls On The Site Components Are removed From
Now the time is to replace the new component. You must be in the utmost careful state at this time. Because something faulty happens this time, this will be very messy and costly to recover.
First, reflow the site after cleaning. Be careful so that you don’t damage the neighboring components. By this time, keep the airflow and temperature in an accurate state. It is one of the most crucial points for replacing the components.
Now, re-solder the new components to the PCB as part of BGA rework. An automatic BGA rework station would be a great solution here to prevent any type of damage.
Here is a video for the complete BGA rework cycle.
How Does A BGA Rework Station Work?
If any fault happens to the SMD or BGA packages, there is a need for a BGA rework station. Also, removing, cleaning, and re-soldering the components again are highly challenging tasks.
So, how do the BGA rework stations work?
The main principle of the BGA rework station is to heat up the PCB for removing the components. By this time, you must maintain the same heat and time cycle for component reflow, as they faced in their first soldering.
By the way, the BGA rework process needs a whole reflow for de-soldering the components. In this case, the automatic BGA rework station uses a software-controlled reflow that maintains the BGA rework station temperature profile.
A BGA Rework Station Works In De-Soldering, Cleaning And Re-Installing Steps
As a result, the heat stays in a controlled state with accuracy for the de-soldering. An automated BGA re-work station is able to do de-soldering, cleaning, and re-soldering the SMD components.
The best BGA rework station has several features. They include heat control for PCB, de-soldering, accurate replacement, solder mask implementation, and re-soldering ability.
The IR BGA rework station uses Infrared Ray for generating heat. By the way, as we mentioned before, the BGA re-work station pre-heats the PCB for properly de-soldering the SMD components.
After de-soldering and cleaning, the BGA re-work station makes ready the PCB for re-installing and re-soldering the components. For this, solder paste should be added to the area to re-install the components.
The reflow process again takes place for joining the solder pads to the component ball grid arrays.
After re-installing, the BGA rework stations let the component and PCB cool. If there are no faults found by testing the rework process, the BGA re-work process is done successfully.
Applications Of BGA Rework Station
From the previous mention, you might get us wrong that BGA re-work is only used when there are faulty components to change. But aside from this, BGA re-work has multiple uses. They are as follows.
- Faulty Component Replacement: replacing faulty components is the biggest use of BGA rework. In electronics, getting faulty components is a common fact in PCBs. So, you need to go through the BGA re-work service.
- Upgradation: Upgradation is another big reason. Sometimes, an upgrade may be needed for necessary purposes.
- Assembly Fault: While assembling the PCB, unwanted faults may occur. Like you may fit the components in incorrect orientation or may get damaged during assembly. In this case, BGA rework is needed for reassembling.
The Types Of BGA Rework Station
The BGA rework station is found in two types that PCB manufacturers use. They are Hot Air BGA Rework Station and IR BGA Re-work Station. Let’s know them briefly.
Hot Air BGA Rework Station
The hot air BGA rework station heats up the components before de-soldering and re-soldering them with the use of hot air. There are many different kinds of nozzles that are used to circulate hot air to the various components.
Hot Air BGA Rework Station
This allows you to effortlessly move the nozzles across a large area. The hot air BGA rework station facilitates the de-soldering of tiny components in a short period of time.
By the way, it is normal for the hot air nozzle to make noise when it is operating. Because it is an ancient technique that is still effective. It should be noted that suitable training and skill sets are necessary in order to operate the hot air BGA station.
IR BGA Rework Station
The IR BGA rework station isn’t the same as the Hot Air BGA repair station. It heats the PCB and components using an infrared ray rather than air.
Along with the Infrared Ray, a fixed ceramic heater is employed. Due to the utilization of infrared rays, there is no noise generation. It is also separated into sections so that you can simply manage it.
By the way, the IR BGA rework station requires a more sophisticated design due to the intricacy of the task. The IR6500 BGA rework station, for example, is one of the finest BGA rework stations for difficult applications.
The IR BGA rework station, by the way, needs further attention. Because it is a newer technology, its adoption is slow.
Here is the operation video of the IR6500 BGA rework station.
Advantages Of Using BGA Rework Station
There are many advantages to using a BGA rework station. They are as follows.
BGA Re-work Station Repairs SMD Components With Ease
- Efficient: You can rework your PCB with the help of highly efficient tools of the BGA rework station. Like specialized nozzles, component pickup tubes, infrared rays, etc., can reliably get jobs done.
With the handling of highly trained technicians, your PCB rework will be done with utmost efficiency
- Accurate Task: Ball grid array requires high accuracy for handling. If you do a mistake when reworking your PCB, you might face the entire destruction of your PCB. So, you need a highly accurate job to be done.
But, you will get the precise accuracy with the BGA rework station to do your PCB rework accurately. Specialized tools allow you to complete everything without any mistakes.
- Large Task Volume: The BGA rework station can handle a bulk rework process at a time for different sized PCBs. So, it will save your time, and effort while doing a large volume of work to be done.
- Cost-Efficiency: You may think a BGA rework station costs you much at a time. But, think about your volume of work to be done along with efficiency and accuracy. The BGA rework station will complete a lot of work with accuracy and efficiency in a large volume. This is highly cost-efficient for your business.
The Hardware Features Of the BGA Rework Station
Most BGA rework stations work in the same way that is allowed by their parts. Different parts have different functions as well. They are as follows.
Hot Air Wand
- Air Flow Grade: you will see a dial on the main hardware of the station called airflow grade. It helps to adjust the flow of hot air.
- Temperature Control: As you know that temperature is the most important part of the rework station, you will find a temperature control feature on the station. It allows the technicians to set the temperature as per needs.
- Hot Air Wand: It is a hand-held tool that is used directly to soften the solder of the components. The hot air comes through this wand.
- Wand Holder: You will find the wand holder beside the BGA re-work station casing. This holds the wand when you don’t use the wand.
- Power Switch: It is the easiest part of the rework station. The power switch allows to power On and Off the machine.
The Common BGA Rework Mistakes To Avoid
As BGA rework needs utmost care and high-level skills, sometimes the following mistakes could happen. These should be considered alarming for BGA rework and should be avoided.
Lacks Of Operator Training
The operator who will use the rework station must be well-trained. He should be well-manipulated with real-life practice with the BGA rework station.
Without solid working knowledge, the operator could drive the entire BGA rework process to the destruction of the PCBs.
The operator should know the measurement of the de-soldering, replacing the components, and re-soldering. Many operators may have failings of proper training. So, this should be avoided for the proper rework process.
Avoid The Common BGA Rework Mistakes
Lacks Of Preparation
There is no matter what type of rework a particular SMD PCB needs. The technician must go through thorough preparation.
There are a lot of things to prepare before going for the rework process. As we have explained the steps of the BGA rework process before, you cannot complete the entire rework process without extensive preparation.
Every fault of the component would not be the same. The technician should research a lot about the particular problem of the SMD component before going through the rework process.
As the ball grid array is a little complex, you must prepare the right measurement of the solder balls. With proper research, the operator can take the instant and right decision about the rework.
But, many operators may skip such extensive research which could drive the rework process to another fault.
Wrong Equipment Selection
Equipment selection is another important fact for BGA re-work. Wrong and inefficient equipment may not be able to fulfill the needs of the rework.
The equipment should not only be reliable and capable of doing the job once, but it must also withstand repetition. The equipment must be able to deliver the proper heat and control them.
It is necessary for your selected equipment to give control over the entire rework process. You will be able to avoid some faults in the rework process if you select the right equipment.
The wrong material selection such as improper solder paste may give you a loose and damaged solder joint.
Poor BGA Profile
You must develop a proper thermal profile for each component you are going to replace with the faulty PCB. BGA rework needs repetition, if the components lack building proper thermal profile, they will be damaged easily.
Improper Inspection After Finishing The Rework
Many operators don’t inspect the completed work after finishing the whole BGA re-work. It may be suicidal for the PCBs. Because, electronics may not properly function, or may face any unwanted accident even after the right rework process.
So, don’t miss to inspect the completed rework.
The Consideration To Choose A BGA Rework Station
If you are a highly skilled technician, you may make your own DIY BGA rework station. But aside from this, when you want to choose the best BGA rework station for purchase, you should consider the following facts about the station.
Temperature Control Feature
The rework station with high precision temperature control feature is the best rework station. You will find the precision heater at the top and bottom of the machine.
You will see the focus heated top and unfocus heated bottom in the hot air stations. Make sure the temperature control feature withstands your needs.
Consider The Temperature Control Feature Of the BGA Re-Work Station
Check the efficiency of the rework station you are going to take. With efficient making and features, a trained person easily can operate the machine and rework the faulty parts.
One of the most important facts about electronics is their maintenance ability. Like hot air rework stations have many parts for maintenance. Improper maintenance could drive them to inefficiency.
Try to select the easy option that allows easy maintenance. For example, IR BGA rework stations have fewer parts to maintain.
BGA rework stations are highly heating-prone as they work with heat. So, focus on the cooling features of the rework stations.
BGA Rework Station Price
Price is another important fact. Cost-efficiency with efficiency and accuracy can make your business super reliable. So, make sure you get the best product with a low BGA re-work station price.
First, make sure which type of PCBs you’re going to rework. Like older PCBs need less temperature, and newer PCBs need a higher temperature. On the other hand, PCB size should be fitted with the stations’ PCB holding limit.
Facts Of Considering To Avoid Error In BGA Assembly
As BGA is a highly advanced technology, there are things to consider to avoid errors in the BGA design. The design team must be in the utmost care state while designing BGA PCBs. They should keep the following things in mind.
The control of heat should be carried out effectively. If there is an imbalance in the grouping of BGAs, it may result in certain thermal difficulties in the device. Closely clustered correctly soldered BGAs, for example, may survive high temperatures, but a less densely packed region may be burned.
On the other hand, if little heat is provided to the BGA region that is less inhabited, the more populous area will not get enough heat.
The design team is responsible for ensuring that the design has the proper footprint. Creating a design that does not fit the PCB pads will result in shorts and soldering troubles on the board.
BGA Footprint Maintenance Is Important for Component Fitting
Placing Of Vias
Keep an eye out for the location of the via. Via is the most often seen feature in multilayer printed circuit boards. The positioning of vias in BGA might have an impact on the solder junctions.
Keep the vias a few centimeters away from the BGA pads. Shorts on solder junctions may occur if this is not the case.
BGA Assembly Inspection
Your BGA design goal is to ensure the proper connectivity with efficiency. But, you cannot visually see the connection between the SMD components and PCBs.
Consequently, there is no alternative to technical inspections so that your BGA assembly gets the exact state you require.
You can go through the following inspection methods to ensure no error on your BGA assembly.
Electrical testing allows you to inspect the electrical properties of your BGAs PCBs. However, it is opposite to the mechanical inspection, where the PCBs may encounter issues with it.
Furthermore, when you do the electrical testing, a current will pass through the BGA. Using this tool, you can determine the electrical stability of your board. The indicator also indicates if the current is on or off once the components have been connected.
If there are any shorts or openings, the electrical test will identify them.
When it comes to BGA assembly testing, X-ray testing is the most sophisticated technology available. As previously stated, BGA will not enable you to visually verify the internal joints; however, an X-Ray examination will resolve the problem.
X-Ray Inspection IS The Most Efficient Testing Of BGA Assembly
Generally speaking, solder junctions are deeper in color than their surroundings. There are no solder joints visible; instead, you can only see the solder pattern. As a result, the solder junction is not visible.
However, if you utilize an X-ray examination, you will be able to analyze both the ball grid and the solder patterns and junctions with relative ease. They may be seen from both a top and a bottom perspective.
The tilt feature of X-Ray inspection allows for the analysis of solder junctions from any location on the component. Excess solder, solder bridges, popcorning, and other similar flaws will be discovered as a result of this procedure.
Visual examination of the BGA assembly and joints is accomplished by optical inspection. Although optical examination has traditionally been performed with the naked eye or a microscope, an endoscope is now being employed.
The endoscope has the capability of inspecting small items. As a result, endoscopes may readily inspect the compact region of BGA joins because of their small size. Inspection of the outer row of the ball grid array with the PCB is aided by the use of an endoscope.
The endoscope is a highly trustworthy tool for inspecting SMT, Through-hole technology, and other types of connections, among other things.
BGA rework demands a great number of skill sets from the manufacturer and reworkers. Any fault with the rework process could also bring destruction to the PCBs.
So, highly skilled and trained people should work with such operations when needed. However, you may rely on trusted PCB assembly services and rework service providers for your BGA rework.
In this case, PCBMay could be your reliable BGA re-work partner.