manufacture rigid flex boards

Rigid flex boards have both rigid and flexible sections, which are electrically interconnected by a ribbon of copper that runs through the board. The circuitry on these boards is designed for both flexibility and structural integrity, allowing them to bend and shape to fit the device they are being used in. Rigid flex boards are often used to connect sensors and actuators to the outside world. These flexible PCBs can be used in a wide variety of devices, including cell phones, laptops, and automobiles.

The process for fabricating a Rigid flex boards begins with creating one or more double-sided flex layers. Fabricators start with either pre-laminated flex with copper foil or unclad PI film and then apply adhesive to the flex. Next, they either laminate or plate up the flex layer with copper using a similar process to standard PCB fabrication. This initial cladding is then etched to reveal the desired circuit pattern.

Drilling the circuit holes and vias is the next step in rigid-flex board production. These holes are usually drilled using high-precision tools and can be as small as 0.002 inches in diameter. Rigid-flex manufacturers usually use mechanical drilling or laser drilling to drill the required number of circuit holes and via patterns. Laser drilling is the preferred method because it can be used to drill extremely small holes, as well as provide precise control over depth.

How do you manufacture rigid flex boards?

Another significant step in the production of a rigid-flex board is adding the final solder mask. The final solder mask can be added as a photo-imageable or screen printed layer onto the bare copper layer on the flex section of the board. It can also be applied to a separate coverlay layer that is then bonded to the flex section of the board. For the best performance, it is recommended to use a hatched ground plane on the areas of the board that are expected to be bended.

After the final solder mask is applied, the board is inspected and tested for quality and reliability. These tests may include thermal stress testing, humidity testing, insulation resistance testing, and voltage endurance testing. Rigid-flex PCBs can also be subjected to environmental testing to evaluate their durability and resistance to corrosion, moisture, flammability, and other factors that might impact their long-term functionality and reliability.

The production of a rigid-flex board requires specialized processes and equipment, which make it more expensive than standard PCBs. However, the flexibility and convenience offered by these devices can offset the higher manufacturing costs. In addition, the cost of producing a rigid-flex PCB can be reduced by minimizing the number of layers, by using a photo-imageable solder mask, and by selecting appropriate materials for the circuitry.

For these reasons, rigid-flex PCBs are often more suitable for medium- to high-volume production, as opposed to low-volume production and prototyping. PCBway has a detailed calculator that will help designers find out how much their design would cost to manufacture. They can also use this calculator to see how much they can save by optimizing their design.