Flexible PCBs: The Future of Electronics Manufacturing

Flexible PCB is called FPC (Flexible Printed Circuit), a quickly growing technology that is used for different electronic projects like automobiles, electro-medical devices telecom sector, and the aviation industry. The use of flexible boards has innovated electrical interconnection methods and is used for connecting different electronic devices. These boards have replaced different types of wiring done by hand reducing the expenses for wiring by about 70 percent.

What are Flexible PCBs?

The flexible PCB board comes with a mixture of different PCBs also components that are configured on a flexible substrate. These boards are also called flexible boards, flex PCBs, and Flex circuits.

These boards are made with the use of components used for rigid PCBs. The basic difference is that the board is made with flexible material for the required structure.

Flexible PCB Benefits

• There are different advantages of this board explained here

Lightweight  Package:

• Flexible boards can easily confined in projects where other boards are not easy to configure These boards are thin less weight and easily folded and configured in parts where other components do not fit.

Accurate Designs:

• Flex boards are made and designed with the use of automated machines. It helps to reduce duces faults that are caused in hand made wires and provides accuracy, that is according to the requirements of devices

East to Design:

• The design of a flexible board does not come with only two layers. They can easily desing in different types. They are made single-sided with a single access, single-sided with double access, and multilayer combination also with rigid and flexible circuits. Their flexible design makes them best for complicated processes.

High Density Configurations:

• The flexible PCBs are a mixture of plated through holes and SMT components. This mixture helps to connect high-density of components with less separation. So denser, less weight conductors are made and free space exists for more components

Flexibility:

• These boards can connected with different planes during use. it helps to reduce weight and space covered with rigid boards. Flexible boards can flexed at different points at the time of use without any damage

Flexible PCB Applications

• Common examples of Flexible boards are
• Avionics
• Airbag systems
• Motion systems
• Satellites
• Antilock brakes
• Bar code equipment
• Battery packs
• Cameras
• Fuel pumps
• Semiconductor testing devices
• Ultrasound probes and other medical devices

Flexible boards Manufacturing Process

• Flexible PCB fabrication requires several stages, including:

1. Substrate preparation

Substrate materials are made that are polymer sheets like polyimide. For making traces on the substrate it is cleaned and covered with an adhesive substance layer.

2. Copper deposition

• The thin coating of copper is applied on substrates through the use of electroless copper plating. Conductive lines that connect different components is made with the copper layer.

3. Imaging and etching

• In this step circuit design shifted on a substrate with the use of a certain printing technique. Photoresist materials are used for transfer design on the copper layers that are made for showing points where copper-etched

4. Drilling and plating

• For vias creation that makes the connection of layers on the circuit, drilling holes on a substrate for component connections

5. Solder mask 

• Solder mask is applied for covering copper traces and components printing on board where label exists

6. Surface Mount Technology (SMT)

In this step, components are connected with the use of SMT on a flexible board. With the use of Pic and place machine accurately connect components on board

Structure of a flexible PCB

The flexible PCB board comes with single-layer, double-layer, or multilayer boards. The main components of single-layer flexible boards are

dielectric substrate film: 

The base materials of the board used polyimide material, which comes with high resistance to traction and temperature.

electrical conductors: 

It is made with copper and denoted traces of the circuit

protective layer,

It is made with the use of a cover coat

adhesive material (polyethylene or epoxy resin), employed for the connection of parts of the circuit together.

Advantages of flexible PCBs

Flexible boards can easily bend and help to make different design configurations and easy connections. Flexible circuits also come with small or irregular-shaped capes, that are not offered by rigid boards.

The main benefit of flexible circuits is they cover less space, and reduce the weight of the board. The use of available spaces provides good thermal management, reduces chances of head dissipation

These boards offer more flexible operation than rigid boards and easily handle vibrations and mechanical stress.

The interconnection standard process based on soldered wires and hand-wired connectors is replaced with flexible boards.

They are low in weight and thickness are come with high mechanical resistance and high resistance for high temperatures.