Flexible PCBs Handle Chemical Exposure

When you’re working with complex electronics like mobile devices and medical equipment that are destined to be used in harsh environments, the durability of your PCB is critical to its function and performance. This includes the ability to withstand mechanical stressors like vibration, bending, or even chemical exposure. Rigid-flex circuits are the ideal choice for many of these environments because of their extremely thin materials and compact size.

To make sure that flex circuits are tough enough to meet these challenges, they undergo rigorous testing and inspection processes during manufacturing. This includes electrical testing to verify connectivity and signal integrity, as well as visual inspection to spot any faults or issues. Once the flex circuit panel has been successfully tested and inspected, it can then be applied with protective coatings and cover layers to safeguard the circuitry and enhance its durability.

The core raw material of a flex pcbs is copper foil, which provides the conductor paths through which signals are etched. It’s essential to choose the right copper foil for a given application, since different types offer differing physical and electrical characteristics. For example, a lower-grade copper that isn’t rolled and annealed will be more susceptible to work-hardening and fatigue over time. Alternatively, a higher-grade flex copper foil that is rolled and annealed will be able to stretch longer before fatigue cracking occurs, providing more elasticity in the Z direction — exactly what you want for a flex circuit.

How Do Flexible PCBs Handle Chemical Exposure?

A flex circuit’s layer stack also plays an important role in its durability. A rigid-flex board’s layer stack can contain any combination of double-sided and single-sided conductive layers, and the conductive layers are interconnected by means of plated through holes. A coverlay (typically Polyimide) is then added to protect the conductive layers and provide insulation for the circuit.

To ensure the durability of a flex circuit, it’s crucial that there are no discontinuities in the bent areas of the panel. This means that vias must not be placed in the flex zone, and a change in conductor width or direction must also be avoided. It’s also prudent to avoid sharp inside corners of the circuit outline to prevent tear formation.

In addition to a robust layer stack, it’s important to utilize a fabricator that carries out thorough material inspection and verification procedures during manufacturing. This includes evaluating the thickness and properties of both the rigid and flexible materials as well as the adhesives that bond them together. A reliable manufacturer will also implement strict quality control processes throughout the manufacturing process to ensure that the final product meets all of the required specifications.

If you’re aiming for rugged flex circuitry that can withstand challenging environmental conditions, trust the expert team at Hemeixin PCB to help you design your flex PCB. With the help of our advanced design software, you’ll be able to easily optimize your designs for manufacturability and use our advanced fabrication services to create high-quality rigid-flex PCBs for demanding applications.