PCB Assembly

Understanding the Importance of X-ray in PCB Assembly

X-ray in PCB Assembly

What is X-ray inspection in PCB Assembly?

The PCB X-ray inspection is one technology employed in the process of making PC boards of the highest quality and reliability, which allows one to easily look inside the multi-layer PCB and detect the flaws that might be hidden but could cause the breakdown, therefore improving the quality of the devices they produce.

The process of assembling electrical components onto the board is called PCB assembly. The PCB works by providing a support structure, which offers the electrical connectivity of the components.  The assembly procedure encompasses various steps which include placing solder paste, mounting the components by automated machines, and soldering the components either by reflow or wave soldering method.

Printed circuit board assembly is an essential part of any electronics manufacturing process where electronic parts are placed on a PCB to make working electronic items. This connection is fundamental because it allows the integration of different devices such as smartphones and medical devices. PCBs are present in almost all electronic devices from the simplest toys to the most complex computers as they are required to do their function properly. PCB assembly is the basis of good electronic devices that are durable and effective.

This article highlights the significance of PCB X-ray inspections. Addressing all aspects starting from the origin to the difficulties that may appear.

The Fundamentals of X-ray Technology in PCB Assembly

PCB X-ray inspection Involves the following:

  • Imaging Technique: This high-energy imaging technique of PCB X-ray inspection is capable of penetrating through PCBs (Printed Circuit Boards). The rays used usually cannot be seen by the human eye. So, instead of unseen, it is now seen.
  • Detection of Internal Defects: The board, after the manufacturing process, does have certain defects such as poor alignment and poor soldering, as well as board circuitry. All this is easy to detect.

Key Advantages of PCB X-Ray Inspection

Through the application of X-ray technology, PCB manufacturers can achieve a higher level of quality assurance, and, subsequently, this system becomes an indispensable part of modern PCB assembly processes.

Detection of Hidden Issues

  • Comprehensive Imaging: With the use of PCB X-ray inspection, the components within the electronic structures become visible. PCB X-ray inspection detects the problems and faults that can be completely invisible from the surface.
  • Early Detection: Identifying possible issues early in the manufacturing process might help save on money and eliminate faults in the end products.
  • Quality Assurance: The possibility to pinpoint the problems and avoid the hidden issues makes every printed circuit board comply with strict performance criteria.

Enhanced Reliability and Safety

  • Discovering such types of defects at the initial phases of manufacturing, the PCB X-ray inspection not only increases the reliability of the PCBs but also greatly minimizes the danger of safety problems in the final products. It is especially important for industries in which failure could result in severe risks, e.g., in aerospace or medical device industries.


  • While X-ray equipment is initially expensive, its long-term returns from fewer adjustments due to rework, scrap rate reduction, and lower repairs mean it is an affordable solution for PCB manufacturers that need top-quality products.

Comparison with Traditional Inspection Methods

  • Visibility: Conventional approaches such as visual inspection or AOI (Automated Optical Inspection) take advantage of surface visibility. In contrast, the PCB X-ray inspection method allows one to have a deeper look below the surface of the PCB.
  • Accuracy: PCB X-ray inspection is much more precise in identifying internal defects that other methods may overlook, particularly in homogeneous and multi-layered boards.
  • Efficiency: Although traditional methods sometimes might be quicker for simple visible defects. PCB X-ray inspection has no substitute for detailed, internal examination, especially if you need to look at complex assemblies such as those with BGA (Ball Grid Array) components inside.

Using PCB X-ray inspection therefore guarantees that every board is produced with the greatest care thereby lowering the chances of failure and the confidence of end-users in the quality of the electronic products is maintained.

Types of Defects Identified by PCB X-Ray Inspection

Soldering Faults

  • Voiding: PCB X-ray inspection can detect voids within solder joints. These can cause the PCB to become weak and cause an eventual failure.
  • Bridging: Solder overflow which provides random connections between conductors can be discovered and modified.

Component Misalignments

  • Skewed Components: Misaligned components can be detected and corrected before the board is finally put together, hence preventing any further challenges.
  • Tombstoning: This can happen if a part is not properly lifted off the circuit board due to bad soldering. This defect can be caught thanks to the PCB X-ray inspection method.

Internal Circuitry Errors

  • Layer Misalignment: PCB X-ray inspection will show if the layers on multi-layer PCBs are not lining up properly.
  • Broken Traces: Undetectable internal breaks in the circuitry by the naked eye can be spotted by using PCB X-ray inspection.

Defects Identified by X-ray Inspection

BGA X-Ray Inspection: A Closer Look

Introduction to Ball Grid Array (BGA)

  • Design and Use: The term BGA stands for ball grid array and these are one of the most common surface mount packages used for integrated circuits. A network of solder balls that are placed under the package is used as links between the PCB. The end result of this is to ensure excellent conduction and heat dissipation.
  • Inspection Challenges: As BGA joints are under the chip they prove to be hard to examine using conventional methods like visual or automated optical inspection which can’t examine below the chip.

How BGA Inspection Works

  • Deep View: Such BGA X-ray inspection enables technicians to see what is going on under the BGA component by looking at the solder joints. It gives them a precise, three-dimensional picture of the part’s structure.
  • Identifying Issues: BGA X-ray inspection is indeed useful because it can locate ordinary BGA transformation problems such as bridging, air voids, and cold joints that may affect the functionality of the product.

Critical Role in Quality Assurance

Ensuring Integrity: BGA X-ray inspection is primarily used for detecting hidden defects and verifying the compositional integrity of those complex structures. This guarantees that the finished products meet the quality standards that are demanded in today’s electronic devices, and they are considered trustworthy.

X-ray Inspection in BGA Assembly

Real-World Applications of PCB X-Ray Inspection

  • Aerospace: Allows the avionic and spacecraft components to be free of defects that are crucial to safety and function in extreme surroundings.
  • Automotive: Confirms the integrity of electronic systems of vehicles, which is critical to operation, security, and performance.
  • Medical: Ensures the reliability of critical devices like pacemakers and diagnostic imaging machines where failure is not tolerated.
  • Consumer Electronics: Maintains high standards in the production of smartphones, laptops, and other daily-use electronic devices.

Challenges and Considerations of PCB X-Ray Inspection

1. Limitations and Challenges

  • High Costs: PCB X-ray inspection installation is often costly, incurring initial investment and periodic maintenance.
  • Technical Complexity: The use of PCB X-ray inspection devices involves trained personnel who understand the features of the equipment and how to detect minute imperfections on PCBs.
  • Interpretation of Results: Occasionally, PCB X-ray inspection images can be complicated to interpret, especially when trying to differentiate between harmless anomalies and severe faults.

2. Overcoming the Challenges and Optimizing the Process

  • Training and Expertise: Sponsoring advanced training programs for operators will equip them with an enhanced skillset to correctly interpret X-ray images and make sound decisions.
  • Technology Upgrades: Taking advantage of advancements in technology. Frequent upgrades of the X-ray equipment will ensure high efficiency and quality.
  • Integrating with Other Methods: A hybrid combination of PCB X-ray inspection along with AOI (Automated Optical Inspection) and functional testing guarantees the integrity of the PCBs.
  • Routine Calibration and Maintenance: Calibration and maintenance of X-ray equipment which helps in the delivery of consistent and accurate inspection results.
  • Data Analysis Tools: The software that is capable of analyzing X-ray images and which highlights the potential problems can greatly minimize human involvement and thus make the process of PCB X-ray inspection much faster.

To overcome these challenges, manufacturers can considerably improve their PCB X-ray inspection by investing in training, technology, and integrated quality assurance processes. This not only enhances the integrity of the PCBs but also streamlines the production flow which in turn results in greater outcomes.

Why Choose Viasion as your PCB Assembly Partner?

Viasion is leading the field of PCB assembly and has made PCB X-ray inspection technology available at your disposal, to provide you with high-quality products. Our usage of the latest PCB X-ray inspection equipment guarantees that we deliver reliability and quality in every circuit board that we fabricate. Through in-depth tests for any inside flaws that may lead to functionality failure, we can be confident that our PCBs reach the very same quality level that our clients expect.

Viasion is not about putting things together; it is about setting milestones in the PCB industry. Our strict quality controls and determination to quality are aimed at not only doing what the industry requires from us but also going beyond.

Trust Viasion for PCB Solutions that puts quality, performance, and reliability at the forefront. At Viasion, we build trust with the most reliable and advanced PCBs.

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