X-Ray Inspection

Everything About X-Ray Inspection

What Is X-Ray Inspection?

X-ray Inspection is a well-developed non-destructive testing method. Currently, many use it in material testing (IQC), failure analysis (FA), quality control (QC), quality assurance and reliability (QA/REL), RESEARCH and development (R&D), and other fields. Technicians use it to detect defects such as delamination, cracks, and voids in electronic components, LEDs, and metal substrates. They also use it to discern whether flaws exist inside the material and determine the shape, orientation, and size of these defects through the contrast of the inspection image.

X-ray non-destructive testing technology in semiconductor packaging and testing has achieved 100% online inspection and is necessary to verify product quality. Under the iterative update of new semiconductor chip technology, x-ray inspection technology is also developing in the direction of high precision and intelligence, keeping pace with the recent trends and requirements of semiconductor packaging and testing.

X-Ray Inspection Principle

The principle of all X-RAY inspection equipment, whether 2D or 3D systems, is that of an X-ray projection microscope, where the X-ray tube produces X-rays through the test sample (e.g., PCB). Depending on the density and atomic weight of the sample material itself, the X-rays are absorbed in different amounts and projected on the image receiver. The closer to the X-ray tube, the larger the shadow, and vice versa happens, which is also the principle of geometric magnification.

X-RAY inspection technology has brought new changes to SMT production. Let us understand the principle of X-ray inspection: All X-RAY inspection equipment, whether two-dimensional or three-dimensional, is an X-ray projection microscope. X-ray emission tube generates X-rays through the test sample (PCB), according to the sample material itself density and atomic weight of the different X-ray absorption amounts. The higher the density of the material, the deeper the shadow. The closer to the X-ray tube, the larger the shadow, and vice versa, the smaller the shadow, which is the principle of geometric magnification. The Venture will explore many more possibilities with this technology!

Why Venture Introduced X-Ray Inspection?

With the rapid development of electronic technology, cell phones, tablets, notebooks, “full hands in the hands” has been out, the integration of smartphones and tablets and other long terminal new category era has quietly arrived. Package miniaturization and assembly of high-density and a variety of new packaging technology to improve the quality of circuit assembly requirements are increasingly high.

As a result, technicians place higher demands on inspection methods and technologies. To meet this demand, Venture has introduced Automatic X-ray Inspection.

Venture uses X-Ray non-destructive inspection to view possible defects in the PCB process, such as poor alignment or defects in open bridges, short circuits, or abnormal connections. It is also used to detect the integrity of solder balls in the package. It detects not only invisible solder joints (e.g., BGA) but also provides qualitative and quantitative analysis of inspection results for the early detection of problems.

Application Areas Of X-Ray Technology

The discovery and development of X-rays provide a new way for industrial non-destructive testing. Its emergence has smoothly become a means for modern industrial production to achieve quality inspection, quality control, and quality assurance. Today, SMT, LED, BGA, CSP flip chip inspection, semiconductor, packaging components, lithium industry, electronic components, automotive parts, photovoltaic industry, aluminum die-casting die castings, molded plastics, ceramic products, and any other special industry testing use X-ray non-destructive testing technology,

Venture Does X-RAY-Welding Inspection In Real Cases

SMT’s first inspection is mainly for the early detection of factors affecting product quality in the production process to prevent products from appearing in batches of super poor, rework, and scrap. It is a means for us to control the product production process in advance, is a required quality control method, and is a proven and essential method. And It is an effective way for Venture to ensure product quality and promote economic benefits. Through the first piece inspection, we can find frequent causes such as BGA welding quality, measuring instrument accuracy, drawings, etc., so corrective or improvement measures can be taken to prevent batch rejects.

Currently, the SMT processing industry uses Non-destructive testing. A wide variety of testing techniques, commonly used first-part testing methods are manual visual inspection, AOI inspection, ICT testing, X-ray inspection, functional testing FCT, etc. Among them, using X-RAY inspection technology with internal fluoroscopy for non-destructive testing is one of the best. It can not only detect invisible solder joints, such as BGA, CSP, and other packaging components. It also allows qualitative and quantitative analysis of the test results, especially for the first part, to identify the problem early.

These First-piece Inspection Methods Above Are Each Characterized As Follows:

1. Manual visual inspection is a method of inspection with the naked eye. Manual inspection is unstable, costly, and imprecise for many welding detectors.
2. Automatic optical inspection (AOI) is used to obtain the image of the device or PCB using CCD photography. And then after computer processing and analysis of comparison to determine the defects and faults. The advantage is that the detection speed and programming time are short. And can be placed in different locations in the production line to facilitate timely failure and defects so that production and detection are into one. The disadvantage is that: it cannot detect circuit properties, such as circuit errors. And the inspection cannot catch the invisible solder joints.
3. ICT needle bed test is a widely used test technology. Testing speed suitable for a single variety of high-volume products. The high cost and long production cycle for the latest highly integrated intelligent products cannot be implanted due to test points and ICT testing.
4. Functional tests (FCT) can effectively find various defects and faults during SMT assembly. Detection is fast, rapid, simple to use, and low investment. Still, it cannot automatically diagnose the flaw, which is not suitable for high-volume testing. And if the circuit board soldering short circuit and not checked in advance to carry out the FCT test is a risk of burning the board.
5. X-ray detection technology’s significant features. According to the understanding of various detection techniques and equipment, X-RAY detection technology has more advantages than the aforementioned detection technology. It can cause our detection system to get a higher upgrade. To improve the “once-through rate” and strive for the goal of “zero defects” to provide an effective means of detection. In particular, technicians can find SMT’s first inspection as early as possible in the production process factors affecting product quality to prevent batch of bad or scrap.
6. The coverage of process defects is up to 97% or more. The flaws technicians can inspect include: false solder, bridge connection, insufficient solder, air bubbles, device leakage, etc. Especially X-RAY for BGA, CSP, and other solder joint hidden devices.
7. Higher test coverage. It can check the places that the naked eye cannot check and in-line test. For example, if PCBA is judged to be faulty and the PCB inner alignment is suspected to be broken. X-RAY can check it quickly.
8. The preparation time for the test has reduced using X-Ray Inspection.
9. It can observe defects that other testing means cannot reliably detect, such as false solder, air holes, poor molding, etc.
10. It requires only one inspection for double-sided and multilayer boards (with delamination function)
11. Based on the first part of the measurement, technicians use the information to evaluate the production process. These include solder paste thickness, amount of solder under the solder joint, BGA placement position, reflow process condition setting, etc.