Flexible PCB Manufacturing & Design Guide
Flexible printed circuit, also known as flexible PCB, is a lightweight and bendable circuit board designed to connect electronic components in limited or dynamic spaces. Compared with rigid PCBs, flexible circuits can fold, twist, and fit into compact electronic designs, making them essential in modern electronic products. At Flex Plus, we provide complete solutions for flexible PCB fabrication, design, and assembly. This page gives you a full overview of flexible PCB structure, materials, manufacturing process, and key applications.
Flex PCB made by laminating a layer of copper foil (usually 17μm, 35μm, 70μm, etc.) to a substrate by hot pressing or chemical deposition, and then etching and other processes. Therefore, the flex PCB does not have a solid rigid support in structure, but relies on its own flexible material to support the layout of the circuit. Flex Plus is able to manufacture ultra-thin flex PCB with a thickness of only 5μm, providing more options for compact, lightweight, and high-performance applications.
What Is a Flexible PCB?
A flexible PCB is a copper circuit laminated on a flexible base film, typically polyimide (PI) or polyester (PET).
This construction allows the circuit to bend or fold without breaking the copper traces.
Flexible PCBs are commonly used in smartphones, medical devices, automotive electronics, and aerospace systems — where space saving and high reliability are required.
See our product types:
Structure and Materials
A flexible PCB is composed of several main layers:
-
Base Film (PI or PET) – provides flexibility and insulation.
-
Copper Foil – forms the conductive circuit.
-
Adhesive (optional) – used in adhesive-based constructions.
-
Coverlay Film – protects the copper traces while allowing openings for pads.
-
Stiffener – adds mechanical strength to connector areas or component zones.
-
PSA (Pressure Sensitive Adhesive) – used when bonding to other parts.
There are two major constructions:
Adhesive type flexible PCB – uses glue between copper and PI layers, lower cost but less heat resistant.
Adhesiveless type flexible PCB – directly laminated without glue, higher performance for fine-pitch or high-temperature designs.
For more design considerations, check our Flexible PCB Design Solutions.
Flexible PCB Manufacturing Process
The flexible PCB manufacturing process requires precision control at every step to ensure dimensional stability and consistent impedance. The general process includes:
-
Base Material Cutting
-
CNC Drilling or Laser Drilling
-
Pattern Imaging and Etching
-
Plating (Through-hole / Surface)
-
Coverlay Lamination and Curing
-
Stiffener or PSA Attachment
-
Profiling and Punching
-
Electrical Testing and Visual Inspection
Each step must maintain cleanliness, accuracy, and temperature control to avoid dimensional shift or copper cracking.
Learn more in our Flex PCB Manufacturing Process.
See also: Flex PCB Testing Services.
Types of Flexible PCB
Type | Structure | Common Application | Image |
|---|---|---|---|
Rigid-Flex PCB | Combines rigid and flexible layers in one board | Foldable devices, avionics, compact control units | |
Multi-Layer Flex PCB | Three or more copper layers | High-end medical, aerospace, or control systems | |
Double-Sided Flex PCB | Two copper layers connected by plated holes | Automotive sensors, battery packs | |
Single-Sided Flex PCB | One copper layer, simple structure | Printers, cameras, LED strips |
Each structure provides different electrical and mechanical performance. For complex 3D assemblies, rigid-flex PCBs combine flexible and rigid sections in a single board.
Advantages and Limitations
Advantages:
-
Ultra-thin and lightweight
-
High flexibility and bend radius
-
Reduced wiring space and assembly weight
-
Excellent thermal dissipation
-
Suitable for dynamic or movable connections
Limitations:
-
Higher material and tooling cost
-
Complex manufacturing and assembly process
-
Requires strict handling to avoid damage
However, with proper design and supplier experience, flexible PCBs can provide unmatched reliability for compact electronics.
Related Resources
Looking for more about flexible PCB manufacturing and applications? Explore these related topics:
TPU Printed Circuit — Stretchable silver circuits for soft robotics and wearables.
FPCB Assembly — SMT and COB assembly for flexible PCBs.
Need a custom flexible PCB solution?
Our engineering team can help you select materials, optimize stack-up, and provide one-stop manufacturing.
Contact Flex Plus for your next project.
PCB flexible esculpida
Estos FPCB tienen una construcción única donde las trazas del conductor se adelgazan o engrosan selectivamente para adaptarse a requisitos mecánicos o eléctricos específicos.
El circuito flexible esculpido común tiene pines que se convierten en conectores de orificio pasante. Los pines terminales esculpidos están integrados y se extienden más allá de los límites del sustrato de poliimida. Estos pines se insertan en una serie de orificios en la PCB flexible y luego se sueldan. Este diseño de circuito también puede soldarse a una serie de almohadillas de montaje superficial. Generalmente, se elige para eliminar la necesidad y el costo de los conectores ZIF.
Terminología de los FPCB
Grabado escalonado / Grabado escalonado
En el contexto de la fabricación de PCB rígido-flexible , "grabado escalonado" o "grabado escalonado" se refiere a un proceso utilizado para crear variaciones de profundidad controladas en las trazas de cobre o capas conductoras de una placa de circuito rígido-flexible.
Este proceso implica grabar selectivamente porciones de las capas conductoras para lograr diferentes espesores de cobre en diferentes ubicaciones de la placa.
El propósito del grabado escalonado es optimizar la flexibilidad y las características de flexión de la PCB rígido-flexible . Al variar el espesor del cobre, la placa puede tener diferentes grados de flexibilidad en distintas regiones, lo que le permite doblarse y adaptarse a la forma deseada sin comprometer el rendimiento eléctrico ni la integridad mecánica.
El grabado escalonado es una técnica esencial en la fabricación de placas de circuitos rígido-flexibles, ya que permite que la placa se adapte a los diversos requisitos mecánicos y se adapte a geometrías complejas, comunes en aplicaciones tales como la industria aeroespacial, dispositivos médicos y otros productos electrónicos donde las limitaciones de espacio y peso son críticas.