BGA Assembly

What Is BGA ?

In terms of BGA assembly, what exactly is a BGA? An IC package consisting of a solder ball matrix of output pins is referred to as a BGA , and it also is It is a type of integrated circuit. The tracer in BGAs has been typically constructed with laminated substrates (BT-based) or polyimide-based films. Thus, the entire area of films or substrates can be utilized to direct the interconnection. As BGAs have a lower ground or power inductance, they can assign ground or power nets to PCBs using a shorter current path

Mechanisms that are thermally enhanced ( heat sink thermal balls, heat sinks, etc.) can be incorporated into BGA in order to lower the resistance. The BGA package technology provides superior electrical and thermal performance for high-power and high-speed integrated circuits. In comparison to traditional SMT package designs, the benefits BGA have over traditional SMT packages. BGA are as follows:

● Ease of electrical and thermal management.
● Ease of routing.
● Higher interconnect density.
● Lower cost of assembly.
● Self-alignment during reflow.
● Low power.

Benefits of BGA Printed Circuit Board

Miniaturization：Reflowing Tin Lead (or Silver) or Gold (or Platinum) with no silkscreen or solder mask 23 pre-set drill sizes up to 200 prototypes per board.

Better Performance：As a result of their low leads, they have a low lead inductance and therefore a high electrical performance.

Low Risk Of Damage：It is easy to maintain and repair PCB boards by using solid solder balls, so the risk of damage to the Printed circuit board is greatly reduced.

Enhanced Thermal Profiles：With a low resistance to thermal, this ensures that the heat generated is quickly eliminated. This in turn makes sure that the chips aren’t being heated.

High Solderability：The assembly process will be sped up as well as the quality will be improved.

Your Leading BGA Assembly Supplier in China

Before the production process before production, our BGA group of assembly technicians will examine all storage conditions of BGA components and create an optimized thermal profile to suit your BGA production process. BGA components are extremely humidity-sensitive and thermally-sensitive components.

In addition to our experience handling micro BGAs to large size BGAs, as well as ceramic BGAs (CBGA) and plastic BGAs (PBGA), we can place BGAs with a minimum pitch of 0.25 mm on your PCB.

Each BGA assembly board goes through an X-ray inspection. With today’s X-ray inspection equipment, BGA assembly problems such as excessive voiding and paste bridges, inadequate ball melting, or improper installation are instantly detected by the X-ray inspection. So we can avoid any soldering issues on the board and offer you a 100% guarantee of quality.

Whatever your profession is, whether you’re an engineer in electrical engineering, a product designer, an integrator, or a maker searching for BGA assembly manufacturers, JarnisTech’s BGA assembly team is the ideal place to start.

By offering 2 hours of quick response time provided by our 24×7 technical and sales support as well as our outstanding after-sales services, We will be your top BGA assembly manufacturer and supplier in China.

At JarnisTech, We can help you with any BGA questions you might be having. We are always available to assist you with your BGA project assemblies, please contact us today , let’s detaill talk everything.

BGA Assembly’s Advantages

● Due to its low thermal resistance, it dissipates heat quickly.
● Reduces the overall thickness of the board.
● Suitable for small packages with high pin counts.
● Improves both thermal and electrical performance while efficiently utilizing space.
● Minimizes the chance of PCB damage as BGA leads are made of well-constructed soldering balls, thereby less time spent on repairs and maintenance.
● Offers better solderability, which results in faster assembly.

BGA Assembly’s Disadvantages

● Inspection difficulty
● BGA is costly
● BGA connections can at times, not be secure

The Most Common BGA Assembly Defects

Due to the complexity of the BGA, there are many possible defects that could be created during the soldering process for the BGA. A few of the issues that could be encountered include:

● Misalignment: The misalignment occurs in the event that both PCB as well as the BGA are not aligned in reflow and then connect at an incorrect location. This is among the most frequently encountered problems that can occur in BGA assembly.

● Standoff Height Inconsistent: Generally, BGAs are soldered on top of PCBs, but improper soldering can cause the BGA to appear at an asymmetric angle. As a result of this asymmetric standoff height, the security of the connections can be compromised.

● Missing Balls: In the case of missing balls on the BGA when attached to the PCB, the assembly may lack essential connection points.

● Non-wetted Pads: There are times when reflowed solder paste does not properly wet the pad. There may be caused by leftover solder resist from previous steps or incomplete reflow in During production

● Bridges: Solder bridges form when excess solder paste is left between paste deposits, causing short circuits.

● Partially Reflown: In some instances, the reflow might not fully cover the board. This is usually due to an insufficient reflow of solder, either by human error or mechanical issues.

● Popcorning: During soldering process, balls merge together and Popcorning occurs. This is a common problem in BGA, resulting in shorts, as they do in bridges.

● Open circuits: When solder fails to wet a PCB pad, it climbs onto solder balls and onto the component surface, resulting in an open circuit. While an electrical test is able to detect this as an issue on a board, however, it is not able to pinpoint the root of the problem.

● Voiding: When a flow stops short of a solder connection, it is referred to as voiding. Typically, collapsible BGA components have this problem.

These problems can result in fatal mistakes for the final product, which is why catching them using quality technology and inspection methods are vital. Fortunately, modern inspection techniques have advanced to the point where most defects can be identified through one or more methods of inspection. However, it’s vital to prevent these problems when possible prior to installation.

Design Considerations To Avoid BGA Defects

While the methods of inspection have evolved to the point that they can spot a variety of defects prior to production, it’s essential to stay clear of mistakes. The process requires careful consideration by members of the design group. To maximize the chances of achieving successfully soldered joints on a BGA, they must take into consideration the following aspects when designing their layout of the PCB:

BGA Footprints

PCB creators must ensure that they have the right footprint layout for any BGA device they plan to make use of. Check the footprint of BGA is correct and ensure that you make a PCB footprint pad in a precise manner to avoid solder shorts and problems during the assembly.

Thermal Management

A PCB layout should take into account the thermal mass. A close grouping of BGAs could create a temperature imbalance between the highly densely populated areas and less populous parts that make up the panel. For instance, applying sufficient temperatures to ensure proper soldering of close groups of BGAs can result in burns in areas that are less populated. In contrast, using enough heat to prevent burning in areas that are less populated could cause voids in BGAs.

Via Placement

Through-holes, are common features of PCBs. However, the position of the via can influence the behavior of the solder during the BGA assembly process. Vias located next to a BGA pad may cause excess solder to flow through the pad and into the via, which causing a short. To prevent this, block any vias near the BGA pad with a solder mask.

It is also important to ensure that a proper reflow profile is developed and verified before assembly in addition to these design considerations. When the board passes through the reflow oven, a profiler measures and logs the temperature range at the BGA ball/pad junction.

This can be done with scrap bare PCBs and BGA parts, this data can be used to ensure the paste reflow profile and the PCB thermal profile are accurate, and to identify any design issues before assembly.

The BGA Assembly Capability of JarnisTech

JarnisTech has a team of professional engineers and advanced machines to deliver BGA packages that are quality and precise. Turnkey services for BGA assembly, as well as other assembly methods, are also offered.

Advanced Equipment in SMT Assembly

We have a completely automatized SMT production line to guarantee high precision and high yields from the entire assembly. Our most recent equipment includes automatic solder dispensing equipment and automatic placement machines Reflow oven as well as X-ray and AOI inspection systems, and more.

BGA Process of Inspection

BGA packages are difficult to examine the solder’s quality because the solder ball lies beneath the chip. Traditional optical techniques cannot determine the presence of defects or cracks inside the soldering joint. In the event that there are BGA components in the SMT assembly, we generally utilize a mixed inspection technique consisting of testing electrically, boundary scanning and automated X-ray inspections in order to increase the accuracy of detection.

BGA Capabilities for Assembly

BGA soldering is typically performed by an automated process because it requires exact control. JarnisTech is able to design and manufacture quality and affordable yield BGA Assembly PCBs to suit your needs. The minimum pitch of BGA we can put together is 0.25mm. We offer these kinds of BGA assembly services:

● Micro BGA
● Micro Fine Line BGA (MBGA)
● Stack BGAs
● Plastic BGA (PBGA)
● Ceramic BGA (CBGA)
● Lead BGA and lead-free BGA

BGAs That Are Supported Are Listed in the Following

● CABGA -Chip Array BGA
● CTBGA -Thin Chip Array BGA
● CVBGA -Very Thin Chip Array BGA
● WLCSP -Wafer Level Chip Scale Packaging
● FCBGA -Flip Chip BGA
● FCmBGA -Flip Chip Micro BGA
● LBGA -Low-profile BGA
● BGA -Ball Grid Array
● BGA -Micro BGA
● DSBGA -Die-size BGA
●  FBGA Fine BGA (also called the Fine Pitch BGA, mainly used to design systems-on-a-chip)
● LGA -Land Grid Array
● CSP -Chip Scale Package

Nowadays, BGA assembly technology has been mastered by a majority of manufacturers. As an experienced PCB manufacturer with years of expertise, JarnisTech provides BGA assemblies that exceed industry standards and with rigorous quality control at the factory. It is recommended to get BGA assembly of your PCBs by a professional. JarnisTech should be your top option.

How Is BGA Installed and Ensure Good Soldering in BGA Assembly ?

BGA Installed

They are set up similarly to the other SMT components. For an effective installation, however, there are some differences to keep in mind:

● A stencil is used first in order to attach solder paste onto the PCB. Proper positioning on the BGA is the next step, which can be performed by an SMT positioning machine or manually.

● BGA components have a characteristic, When the solder hardens and solidifies, BGA components self-align, which helps with imperfect placement. Leads are then connected to the PCB by heating the component.

● When using a reflow oven, proper precautions are taken to adjust the oven settings for good solder connections. The component can be maintained in position by using a mount when soldering by hand

Ensure Well Soldering BGA Assembly

● It is essential to apply enough heat to melt all the balls in the grid so that each BGA solder joint is fully bonded.

● In the process of cooling and solidifying the solder, the surface tension of the molten balls holds the BGA package in place. To ensure quality solder joints, a temperature-controlled soldering process must be followed. This practice prevents short-circuits between solder balls.

● It is important to choose the solder alloy configuration and heating temperature carefully, so that the solder doesn’t completely melt but remains semi-liquid. This permits each ball to remain distinct from the other balls. Make sure you adhere to the temperatures for reflow provided by the manufacturer of your component.

How Do Test the Quality of Solder Joints the BGA ?

Optics techniques aren’t suitable for inspecting BGAs because solder joints are hidden in their BGA components. In addition, the electrical tests aren’t terribly reliable as they only reveal how electrically conductive the BGA is at a specific moment. They don’t give a reliable indication of whether the solder will last or not. The solder joint might actually fail after a certain time.

In contrast to electrical tests, X-rays can be used to examine the BGA solder joint. It aids in looking through the solder joint underneath the BGAs. This is why AXI, the automatic X-ray inspection (AXI) procedure is extensively used for BGA inspection.

Why Is Inspection Important ?

It is notoriously difficult to inspect BGA packages because the solder joints are located beneath the package. Because of this feature’s position, it can be challenging to get a good view of the BGA for inspection. Despite this difficulty, Inspection is essential for BGAs for several reasons, including:

Soldering Difficulty

Soldering BGA components can be a challenge because it requires enough heat to be applied to the array, so that all the balls on the grid melt to the point of making solder joints. The density of connections and the difficulties of soldering means there’s the possibility of a problem occurring. Inspections can help professionals spot these issues so that they can prevent sending out defective parts.

Unreliable Electrical Tests

In electrical tests, a current is run through the PCB to determine whether it is electrically sound. but this type of test can only determine whether the current is on or off when the BGA components are connected. These tests are not reliable since they are only able to find a handful of defect types and cannot pinpoint the locations of any defects they find. Comprehensive inspections that combine this method with other techniques can create a complete overview of errors and their

Material Reuse

When a BGA has a solder defect, it can be removed using a rework station, and repaired or refurbished for reuse. Inspections can detect defects earlier so that the components can be saved this way and reduces the amount of waste.

Quality Control

BGA SMT assemblies rely on good physical connections. Therefore, BGA quality control should include a thorough examination of the connections.

A thorough inspection can also detect common defects and patterns. These are important, as repeated defects may indicate an issue with the manufacturing and assembly process or even with the design of the PCB product design.

Cost Reduction

Inspections that are thorough reduce the number of errors that are passed on to the next phase of production. Incorrectly identified defects could be discovered later during the manufacturing process and rework more expensive. If you catch a defect late, the more cost it will be for your company in the long run. That’s why early prevention and resolution are crucial.

Key Points of SMT Assembly Process for BGA Components

Pretreatment

While some components that have BGA packages aren’t so susceptible to humidity, all of the components should bake at 125°C since no adverse effects have been observed on baking at low temperatures. This is also true for PCBs that are bare (printed circuit boards) which are now prepared for SMT assembly. In the end, moisture will be removed first with the defects in soldering balls decreasing and solderability increasing.

Solder Paste Printing

Based on our experience with assembly and experience, printed solder paste is typically straightforward to use on BGA components that have pitches of greater than 0.8mm and QFP components that have pitches of 0.5mm. However, occasionally, there may be a problem where tin has to be compensated by the manual process because certain solder balls aren’t receiving sufficient printing of solder paste, which causes soldering to be dislocated and short circuits to form.

But, in our experience, it does not seem that solder paste can be printed more easily on BGA components with a 0.8mm pitch than on QFP components with a 0.5mm pitch. We think that a lot of engineers are conscious of the distinction between vertical and horizontal printing QFP with a pitch of 0.5mm, which is explained from the standpoint of mechanics. So, some printers can provide the 45deg printing feature. Based on the belief that printing plays an important part in the assembly of SMT, It is recommended that adequate attention be given.

Placement and Mounting

Based on experience from the assembly, since physical characteristics cause BGA components to offer excellent manufacturability, they can be easier to mount than QFP components that have pitches of 0.5mm. But the primary issue we are faced when it comes to the SMT assembly is that the vibration typically occurs on components when large-scale rubber ring nozzles are utilized to mount components on circuit boards that have dimensions of greater than 30 mm. In the light of analysis, it appears to be caused by too high pressure within the nozzle due to excessive mounting strength, which can easily be eliminated by modifying the mounting strength.

Soldering

Reflow soldering by hot air is an unintuitive process in the assembly of SMTs or can be described as unique technology. While BGA components have the same time and temperature curves for soldering, they have a distinct curve that is different from traditional SMDs in the way of the reflow soldering process.

Solder joints in BGA components are situated under components and are located between the component body and PCB. This means the fact that BGA components are more impacted through solder joints than standard SMDs because the pins of the latter are situated at the edges of the body of the component.

In the least, they are directly exposed to hot air. Calculating thermal resistance and other methods suggest that solder balls in the central region of the BGA body are afflicted by thermal postponement, slow temperature rising, and a very low maximum temperature.

Inspection

Due to the physical properties that are present in BGA components, the visual inspection is not able to meet the inspection demands for solder joints that are hidden in BGA components, and so the X-ray inspection is required to detect soldering flaws like short circuits, voids and soldering balls that are missing air holes, for example. The only drawback of the X-ray inspection is its high price.

Rework

In addition to the wide array of possible uses for BGA components, as well as the growing popularity of electronic devices for personal telecommunications, BGA rework has become more important. But, When BGA components are removed from the board, they cannot be used again, unlike QFP components.

In the present, when BGA packaging technology is now the norm for SMT manufacturing, the complexity cannot be overlooked and the most important aspects. When choosing the electronic contractor manufacturer (or assembler), a reputable manufacturing line is recommended to be picked along with complete assembly capabilities as well as assembly equipment.

Applicatioms of BGA PCB Assembly

Ball Grid Array (BGA) Assembly has a wide range of applications in a variety of fields that include but are not only:

● Automotive industry.
● Military applications.
● A variety of electronic devices, including televisions, mobile phones and many more.
● Other consumer electronic devices. Devices that are smaller are more likely to utilize them.

Conclusion

BGA Assembly Package is extremely vital to technological advancement in the modern world.

Although it does have certain flaws but its impact on industries that manufacture electronic devices has proven to be efficient, reliable and of excellent quality.

As technology improves, there is a chance that the BGA assembly system will keep on advancing.

This is due to the growing interest in the application of BGA assembly technology in the majority of electronic manufacturing companies.

Related Posts:

1.Inspect a Solder Joint BGA: You Need to Know Everything

2.The Complete Guide to µBGA Technology