With the rapid development of LSI technology, the through-hole technology (THT) that flourished in the 1960s has gradually been replaced by the first generation of surface mount technology (SMT), which emerged in the 1980s. By the late 1970s, peripheral packaging had become the mainstream of electronic packaging, and QFP packaging had been widely adopted. In the 1990s, QFP packaging witnessed a fine pitch and leading board assembly technology; however, many technical issues remained unsolved in the assembly of board-level circuits with less than 0.4mm pitch. Thus, the second generation of SMT, ball grid array packaging (BGA), was launched in the early 1990s and became the preferred solution. Particularly after the adoption of flip chip technology, PBGA started to be widely used in supercomputers and workstations. The third generation of SMT is direct chip assembly (DCA), which is only used in specific fields due to limitations in reliability, cost, and KGD. In recent years, the third generation SMTs have been using wafer-level packaging (WLP) and advanced flip-chip technology to be compatible with semiconductor multi-pin and high-performance requirements. Thus, it can be concluded that IC packaging in the 21st century will develop towards the trend of high density, fine pitch, high flexibility, high reliability, and diversification. Therefore, it is essential to understand the difference between QFP and BGA and their development trends. https://www.fs-pcba.com/

Comparison of BGA and QFP

BGA components are typically very durable and can continue to function even if they are dropped, which is not possible with PQFP. The advantage of BGA lies in its array form, as BGA components usually provide more I/O than QFP under the same area. When the number of I/O exceeds 250, the size of BGA is always smaller than that of QFP. The larger pitch of BGA also makes it easier to install and relatively more efficient. BGA assembly failure rates due to testing and packaging-related defects before assembly can be lower than 1ppm.

The biggest challenge in BGA assembly is the issue of package-related defects, which can be caused by missing solder balls, moisture sensitivity, bumps during shipping, and excessive warpage during reflow soldering. The defect rate allowed for BGA assembly is the lowest, and there may be double-layer solder balls and metallization-related defects at the solder joint position, such as insufficient soldering between the solder balls and the component pads.

The BGA package is characterized by having shorter leads than QFP, resulting in excellent electrical performance. However, the cost of BGA is its biggest drawback, as BGAs are more expensive than QFPs in terms of laminate and resin costs associated with substrate-carrying components. BGAs use higher-cost BT resins, ceramic and polyimide resin carriers, while QFPs use lower-cost plastic molding resins and sheet metal lead frames. Array carriers have considerable cost due to delicate wiring circuitry and chemical processing techniques. Additionally, QFP can apply high-volume molding dies and molding equipment, reducing packaging process steps compared to BGA packaging.

Regarding BGA package cost, the most common BGA packages suitable for the number of I/O pins contain all circuitry on the sides of the package carrier and have no defined vias, leading to additional costs. However, the efficient assembly speed of BGA package can make up for its high cost to a certain extent. From an economic value perspective, QFP is more suitable when there are less than 200 I/O pins. When the number of I/O pins exceeds 200, various types of BGA packages can be applied instead of QFP.

BGA assembly fits with medical PCB

When manufacturing medical electronic devices, it is crucial to choose the correct PCB assembly method. PCBA manufacturers must consider various factors such as reliability, safety, and quality control. In medical PCB assembly, BGA assembly is usually the preferred assembly method.

Medical devices require high reliability and stability, and BGA assembly can provide these requirements. BGA components are better equipped to disperse and handle heat, making them better suited to withstand high temperatures and humidity than traditional QFP components. Additionally, BGA PCB components can provide higher impedance control and signal integrity, which is vital in medical electronic equipment.

Another important factor is that medical devices often require smaller, lighter, and more compact designs, and BGA components can help achieve these goals. BGA components are smaller than QFP components and can take up less space, resulting in more miniaturized medical devices. Additionally, BGA components can improve manufacturing efficiency and reduce assembly costs because they can be assembled automatically by machines. https://www.fs-pcba.com/medical-pcb/

Of course, quality control and reliability are paramount in the medical PCB assembly process. This requires selecting an experienced PCBA manufacturer to ensure product quality and production efficiency. These manufacturers must adhere to industry standards and safety practices, and have top-notch quality control systems to ensure the reliability and safety of medical electronic devices.

In summary, BGA assembly inmedical PCB has many advantages, including high reliability, stability, smaller size, and higher manufacturing efficiency. However, selecting the right PCBA manufacturer is critical to ensuring quality and safety. https://fs-technology.bravesites.com/entries/general/BGA-assembly-technology-used-in-medical-PCB