FR4 CCL quality directly affects the quality of printed boards. The main non-electrical technical standards for measuring the quality of CCL are as follows:
The peel strength is the minimum force required to peel the substrate from the copper foil per unit width, and the unit is kg/cm. Use this indicator to measure the bond strength between the copper foil and the substrate.
Warpage refers to the warpage value per unit length, which is a measure of the unevenness of the FR4 CCL for PCB board relative to the plane, depending on the substrate material and thickness.
3. Bending strength
The flexural strength indicates the ability of the PCB CCL to withstand bending in kg/cm. . This indicator is mainly determined by the substrate material of the copper clad laminate. This indicator should be considered when determining the thickness of the printed board.
4. Dip resistance
Shear resistance refers to the copper stripping resistance of Copper Clad Laminate after it has been placed in molten solder at a certain temperature for a period of time (usually 10 s). Copper foil sheets are generally required to be non-foaming and non-layering. If the soldering property is poor, the printed board may peel off the pads and wires after multiple soldering.
In addition to the above indicators, the technical indicators for measuring FR4 CCL are surface smoothness, smoothness, pit depth, dielectric properties, surface resistance, and cyanide resistance.
ZTELEC FR4 CCL has been developed through years of research and development, with high frequency, high CTI, low CTE and so on.