Copper Clad Laminate

Nowadays, a large portion of devices and equipment are electronic. This translate to an increasing demand for efficiently designed electronic components, such as printed circuit boards (PCBs). One of the most important procurement decisions that enterprises in the PCB industry must make is to select suitable individual components for the circuit boards, particularly copper-clad laminates.

Copper-clad laminates: function and fabrication

Copper-clad laminates (CCLs) are a type of base material for PCBs. Copper-clad laminates essentially serve as an embedded capacitance material that strengthens the stability and reliability of electronic circuit boards. PCB copper-clad laminates typically consist of prepreg, copper, and dielectric coating. Prepreg, referred to as “bonding sheet” or simply “preg,” is a reinforcing material that is made of epoxy resin, glass fiber, DMF, 2MI, and acetone. The prepreg is responsible for supplying the required insulation of copper-clad laminate sheets.

As the name suggests, copper-clad laminates and copper-clad boards are fabricated through copper lamination. This process requires three key steps: treating, lay-up, and pressing. During the process, copper foil is laid on top of a flat stainless steel plate, followed by layers of prepregs. The number of layers determines how thick or thin the laminate will be. After stacking the desired number of layers, heat and pressure are applied to press and cure the laminates.

Classifications of copper-clad laminates

Copper-clad laminates sheets for PCBs can be classified based on different categories:

By reinforcing material: paper-based CCL, glass fiber-based CCL, compound CCL, and special material-based CCL (e.g., metal-based and ceramic-based CCLs)

By insulation resin: phenolic resin CCL, epoxy resin CCL, and polyester resin CCL

By performance: general-performance CCL, CCL with high heat resistance, CCL with low dielectric constant, and CCL with low coefficient of thermal expansion

By mechanical rigidity: rigid copper-clad laminate and flexible copper-clad laminate

Different types of copper-clad laminate are available in the market. Copper-clad laminate manufacturers often mass produce these components, which in turn allows global suppliers to offer cost-efficient deals for wholesale copper-clad laminates.