Key Factors in PCB Material Selection
Guangzhou Highleap Electronic Co.,Ltd.
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Choosing the right materials for PCB fabrication is crucial in today's world of advanced electronics and high-speed signals. Different materials offer varying performance and properties, starting from FR-4 for standard applications to high-speed materials like Teflon.Followings are some keys you need to pay attention：
1、The Most Common Types of PCB Materials
This material is a National Electrical Manufacturers Association (NEMA) grade of flame retardant laminate that contains an underlying layer of woven-glass fabric and resin binder of epoxy. FR4 has been around for at least 50 years and has evolved, with continuous operating temperatures now up to 180°C. FR4 doesn’t, however, have the best coefficient of thermal expansion (CTE) and electrical characteristics for high-quality signal speed, which is why the material is being used less frequently in PCB fabrication.
Designed to operate in digital products that have higher signal speed and higher signal integrity requirement and must withstand higher temperature ranges. There are different resin systems that fall in between FR4 and Teflon that are also used as signal speeds increase.
This material is often used in radar applications and for any type of high-speed communications, such as satellite dishes. It can also better withstand the environment than FR4 and other resin materials.
Copper is the main conductive metal used in the construction of PCBs.
2、Key Considerations
It’s important to start with a prototype and consider overall design elements, what the board will be used for, followed by signal integrity requirement, and how it should function in varying environments.
Take signal integrity requirements into account and consider its performance in various environments, including its ability to withstand high temperatures. Additionally, determine whether a flexible or rigid board is the optimal choice.
?High-speed signals and power-intensive components can generate significant heat during operation.Materials with good heat conductivity help maintain signal integrity and minimize the risk of signal loss, jitter, or other signal-related problems.
A PCB material with high thermal resistance may experience thermal stress during temperature fluctuations, which can lead to mechanical failures, delamination, or warping. Choosing a material with appropriate thermal properties enhances the reliability and lifespan of the PCB, reducing the risk of premature failure.
The stackup affects the impedance and thermal performance. Different layers of materials have varying thermal conductivities and dissipation capabilities. An optimized stackup can efficiently dissipate heat generated by high-power components, preventing overheating and ensuring stable operation of the PCB.
The stackup affects the mechanical strength and rigidity of the PCB. Depending on the application and environmental conditions, the choice of materials and layer arrangement can provide the necessary mechanical support and durability required to withstand mechanical stresses and vibrations.
The proximity of components to each other and to signal traces can introduce signal interference, crosstalk, and noise.Certain PCB materials may have better electrical properties, such as lower dielectric loss and lower signal attenuation, which can help preserve the integrity of signals traveling between components.
The arrangement of components can influence the electromagnetic emissions and susceptibility of the PCB. Careful component placement, along with the use of PCB materials with good EMC performance, can help reduce interference and ensure compliance with electromagnetic compatibility standards.
Flexibility is a crucial aspect to consider when choosing a PCB material. When a multi-layer circuit board is designed with a combination of flexible and rigid materials, it becomes a rigid-flex board. This unique configuration allows the board to be bent and folded into various shapes, making it a versatile 3D interconnect.??
The cost of materials typically increases when the printed circuit board contains gold, blind or buried vias, or via filling. This is because an alternate process is needed for fabrication. Line and width spacing below 6 mils may also increase the cost. An ENIG surface finish layer is one of the best ways to protect the surface of a printed circuit board.
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3、Consult the Experts
Selecting the incorrect materials can significantly delay your PCB project or affect your budget, underscoring the importance of seeking advice from experienced professionals from the outset.
Arlon：High-performance polyimide laminate and prepreg materials
Dupont：The broadest array of electronic materials for flexible and rigid-flex circuits
Megtron：Low DK with better stability than PTFEs
Isola：High speed Copper-clad laminates and dielectric prepegs
Rogers：Enabling step changes in high-frequency, high-speed performance for wired and wireless communications
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At Highleap, we take pride in our industry-leading procedures, state-of-the-art facilities, and highly skilled team, all dedicated to meeting your custom PCB manufacturing requirements.