BGA packages are commonly used in the electronics industry. Electronic devices keep becoming smaller every day. All thanks to BGA packages. The advancement in technology and electronics development has increased the needs for BGA packages.
The Ball Grid Array (BGA) is the brain behind the small sizes of electronic devices. Also, BGA packages are commonly used to mount devices permanently. BGA is widely known for its high lead count and compact size. Let’s focus on what BGA electric is all about?
Types of BGA Package
There are different types of BGA Packages. This classification is based on the materials used.
Ceramic BGA
The ceramic BGA package features a ceramic substrate. Also, this BGA package works with flip chips. The LGA and CCGA package types are under this category. Also, the CBGA packages need more pins than PBGA packages. However, some applications demand ceramic BGAs.
The solder balls of ceramic BGA feature a 10 percent and 90 percent lead composition. This helps to enhance reliability and get rid of the differences between the CTE of the substrate and board.
Tape BGA
The tape BGA creates fine lines on solder balls by using a flexible interconnect. Therefore, this package type offers great thermal performance. The metal BGA is similar to the tape BGA. This is because the MBGA utilizes an aluminum substrate in a simple design. Both tape and metal BGA feature the same thermal and electrical performance.
Plastic laminate BGA
The plastic BGA features a plastic substrate. The solder balls in this package comprises 37% lead and 63% tin. Also, this substrate can withstand temperatures of about 1500C. Polyimides and dry-clad are examples of material used for this BGA. Also, the BT epoxy glass is a common material used for this BGA.
In addition, plastic BGA can allow flip-chip designs. Therefore, this helps to enhance connectivity between the PCB and the package.
Benefits of BGA
Greater thermal performance
BGA packages offer greater thermal performance. Also, these packages ensure quick and easy dissipation of heat.
High speed performance
The conductors of a BGA are on the underside of the chip carrier. Therefore, there are shorter leads within the chip. There is high speed performance due to the conductors positioned under the chip carrier.
Lower thermal resistance
BGA packages offer lower thermal resistance. Also, they allow heat generated in the IC inside the package to conduct faster on the circuit board.
Improved electrical performance
BGA packages feature no pins. Therefore, this makes them stable enough. This ensures great electrical performance.
Reduced costs
The effective and efficient use of PCB space helps to save material. Also, it enhances thermoelectric performance. The reduced space helps to reduce the risk of defects. Also, reduced space helps to reduce overall cost.
Efficient use of PCB space
BGA packages use fewer components. Also, the smaller footprints of BGA help to reduce the use of space on PCBs. BGA packages have also contributed to the production of smaller and more compact electronic devices.
Lower track density
On a quad flat pack, the package pins are very close. Therefore, this leads to high track densities. However, this is different in the BGA package. Also, BGA package spreads the pins over the whole surface of the package. Therefore, this helps to reduce track densities.
Common Defects in BGA Electric
There are some common defects or problems that may arise in BGA. These potential problems arise due to the complexity of the BGA electric.
Misalignment
This occurs when the BGA and PCB are offset and connect at incorrect areas. Misalignment is one of the most common defects that happen during BGA assembly.
Bridges
This problem happens when there is extra solder paste between paste deposits. Also, bridges can cause shorts when it occurs between connection points.
Open circuits
Open circuit happens when solder doesn’t wet the PCB pad and then climbs on solder balls. An electrical test can detect this problem. However, it can’t detect the cause of this problem.
Missing balls
This occurs when important connection points are missing from the assembly. If there are missing balls from a BGA package, it could cause further problems.
Partial reflow
When the reflow doesn’t cover the board, it could cause some defects. Also, this problem happens due to insufficient solder reflow. However, it could be as a result of mechanical malfunctions or human error.
Non-wetted pads
If reflow solder paste doesn’t wet the pad well, this might cause a problem. Also, non-wetted pads may result from leftover solder resist or incomplete reflow.
Inconsistent standoff height
This problem is a result of improper soldering. Also, PCB manufacturers place BGAs on top of circuit boards. Improper soldering can cause BGA setting at a crooked angle.
How to Inspect BGA Electric
Inspecting BGAs for any defect is necessary. Also, the goal of any BGA process is to avoid any defect.
Electrical testing
This is an inspection process that evaluates the electrical properties of the board. Electrical testing doesn’t expose the BGA to shock. Therefore, it is an acceptable technique of BGA testing. Also, electrical testing analyzes the electrical stability of the PCB. This test determines if the current is off or on after connecting the BGA.
The electrical testing helps to identify problems like openings or shorts. However, electrical tests can’t meet all the assessment requirements. Therefore, it is advisable to combine this test with other tests.
X-ray inspection
Another reliable way to inspect BGAs is through X-rays. This technique is an advanced inspection method. Here, X-rays go through the board at varying amounts. The detector then translates the X-ray into visible light and produces an image.
Visual inspection
This inspection method uses optics technology to evaluate a BGA and its connections. The endoscope is a device that helps to visualize the BGA and its components. This device uses a camera to have close-up images of an area.
Conclusion
BGA packages are becoming more popular in the PCB industry. This technology helps to achieve ground inductance implementation. A well-designed BGA will provide better enhancements in crosstalk. We have provided important information about BGA performances in the PCB industry.
