PCB Material Selection Guide

Key factors
Thermal management: The limits of the temperature and the ability of the board to lose heat are important controllable parameters. For such applications where high heat dissipation is a necessity, aluminum or copper-clad laminate (CCL) boards are more appropriate.

Electrical factors: Focusing on the dielectric constant (Dk) and dissipation factor (Df) these are some of the electrical factors which have a direct impact to how signals are processed. Such high frequency applications as RF circuits are carried out in materials of low Dk and Df to avoid delay and loss of signals.

Mechanical strength: This is crucial especially when mounting the PCBs, in most cases, they are subjected to mechanical forces such as varying stress levels, vibrations or flexion’s. Rigid type PCB materials FR-4 which is an epoxy resin fiberglass reinforcement with flame retardant property are used while flexible PCB FPC of polyimide or PET are used where flexibility is required.

Cost and availability: The variations in the costs of PCB materials are wide ranging and are attributed to several factors such as the prices of the raw materials used, the manufacturing techniques and processes and even the logistics involved. SHEN CHUANG provides a range of materials with the necessary capabilities and performance strengths at competitive prices, giving clients a personal budget for them to work with.

Environmental considerations: The issues of sustainability have made the use of materials in the making of PCBs a pertinent issue. The preference for materials that are safe such as RoHS compliant materials that can be made from recycled materials or bio-degradable materials has increased.

Common PCB materials
FR-4: FR-4 is quite often the material of choice for PCB’s because of its optimum electrical, thermal and mechanical properties. General PCBs applications can be performed with its use and is reasonably priced.

Polyimide: Polyimide has high thermal stability and great flexibility and is mostly used in FPCs where toughness and flexibility are needed such as in smartphones, and wearable electronics.

Aluminum-backed PCBs: This type of PCB has an outstanding thermal management property thus can be useful for applications such as LED lighting imbedded power electronics and any other where heat removal is of paramount importance.

PTFE (poly tetra fluoro ethylene): Among the highly electrical insulators seamless PTFE is the best there is.