Cavity PCB, also known as printed circuit boards, are essential components in modern electronic devices. They play a crucial role in connecting and supporting electronic components, ensuring the proper functioning of various gadgets, from smartphones to computers. In this article, we will delve into the specifics of Cavity PCBs, focusing on their material, thickness, surface treatment, and advanced technologies, including stack-up configurations, minimum track/width, blind & buried vias, and laser vias.

1.Material: FR4

FR4 is a commonly used substrate material for PCBs. It is a flame-retardant, glass-reinforced epoxy laminate that offers excellent electrical insulation properties. FR4 is known for its durability, dimensional stability, and cost-effectiveness, making it a popular choice in the electronics industry. Cavity PCBs made from FR4 are suitable for a wide range of applications due to their reliability and versatility.

2.Board Thickness: 1.6mm

The thickness of a Cavity PCB is a critical parameter that can influence its performance. A standard thickness of 1.6mm is commonly used for many electronic applications. This thickness strikes a balance between mechanical strength and flexibility, making it suitable for various device designs. However, Cavity PCBs can be manufactured with different thicknesses to meet specific requirements.

3.Surface Treatment: Immersion Gold

Surface treatment is essential for protecting the PCB from oxidation, ensuring good solderability, and enhancing its overall performance. Immersion Gold, also known as ENIG (Electroless Nickel Immersion Gold), is a popular choice for surface treatment in Cavity PCBs. It provides a thin, uniform gold layer on the exposed copper traces, offering excellent corrosion resistance and ensuring reliable solder joints during assembly.


a. Stack-Up N+N

The stack-up configuration of a PCB refers to how the various layers are arranged. In the case of Cavity PCBs, the N+N stack-up means that the board has multiple layers, and each pair of layers constitutes a core and prepreg combination. This configuration allows for increased routing and component density, making it suitable for complex electronic designs where space is at a premium.

b. Minimum Track/Width: 3/3mil

The minimum track and width dimensions in Cavity PCBs are critical for defining the conductive pathways on the board. With a minimum track/width of 3/3mil, Cavity PCBs can accommodate fine-pitch components and intricate circuit designs. This specification enables the board to handle high-density circuitry, making it suitable for advanced electronics.

c. Blind & Buried Vias

Blind vias and buried vias are advanced via technologies used in Cavity PCBs. Blind vias connect an outer layer to one or more inner layers of the board, while buried vias connect only inner layers. These vias help route traces through the multiple layers of the PCB without passing through the entire thickness. This technology allows for increased routing flexibility and can reduce signal interference, enhancing the overall performance of the board.

d. Laser Vias

Laser vias are a cutting-edge technology used in Cavity PCBs. They are created by laser drilling small holes in the board to establish connections between layers. Laser vias offer precise control and high accuracy, enabling the creation of intricate and densely packed PCB designs. This technology is particularly beneficial for miniaturized and high-performance electronic devices.


Cavity PCBs made from FR4 material, with a thickness of 1.6mm and immersion gold surface treatment, represent a versatile and reliable choice for electronic applications. Their advanced technologies, including stack-up configurations, minimum track/width specifications, blind & buried vias, and laser vias, enable them to meet the demands of complex and high-density circuit designs. As electronic devices continue to evolve and demand smaller, more efficient PCBs, Cavity PCBs with these features play a vital role in pushing the boundaries of technology.