UV picosecond laser cutting
There are many kinds of FPC flexible circuit boards common in the market today. Single-sided cardboard, fr4 single-sided, double-sided, multi-layer board, single-sided aluminum substrate, single-sided fpc, high-frequency board, etc. Surface treatment process: over rosin, osp, tin spray, lead-free tin spray, gold plating, immersion gold, immersion silver.
For FPC, the protective effect of polyimide film is the same as that of FR4-based printed circuit board (PCB) solder mask. Polyimide is usually 12 to 25 µm thick, is coated with a pressure-sensitive adhesive, and is connected to a paper-based material. The key challenge is to ablate the patterns in polyimide at high speeds while avoiding thermal effects such as adhesive melting and paper-based combustion / carbonization. The current state-of-the-art protective film mapping process is a combination of a pulsed nanosecond UV laser and a two-dimensional galvanometer to achieve high-speed processing with low thermal effects. However, in some applications, quality is critical, so UV picosecond pulse widths are more advantageous.
Compared with the nanosecond UV laser, the picosecond UV laser generates fewer fragments, and can be processed at a higher pulse frequency (and therefore at a higher speed), without causing inconvenience in the adhesive and paper base. Necessary thermal effect.
Choose ultrafast laser UV picosecond laser cutting machine, which can be used to process various FPC materials. Processed materials include polyimide-based protective film (25µm thick polyimide + adhesive layer on paper substrate), copper / liquid crystal polymer / copper (Cu / LCP / Cu) laminate, and bare liquid crystal polymer (LCP) materials. LCP is an important dielectric material for high-speed radio frequency (RF) data transmission technology.
In many cases, shorter ultraviolet (UV) wavelengths bring additional benefits. Shorter wavelengths enable smaller focused spots and longer processing field depths. In addition, ultraviolet wavelengths can couple laser energy into a wider variety of materials than infrared wavelengths. One of the industries that combines many different materials is flexible printed circuit (FPC) manufacturing. Therefore, UV picosecond laser cutting machine is undoubtedly a better solution for high-quality flexible circuit board processing. This greatly improves the quality and output of laser processing.