As the principle of CO2 laser ablation, circuit board manufacturers using conventional carbon dioxide laser (or one step) to complete PCB microporous processing is not desirable. Due to the high energy density of the CO2 laser beam, carbonized (insufficient or too little oxygen) residue forms on the "bottom copper" (land) or forms a drum-shaped blind hole or causes the PCB "bottom copper" lands (Over temperature) the bottom surface and the internal dielectric layer separation defects, these defects will bring the reliability of PCB circuit board quality problems. However, when carbon dioxide laser energy density is low, circuit board manufacturers are faced with slow speed, low productivity, or fiberglass cloth (silk) cut (if the RCC does not exist this problem), or glass fiber fuse convex Out, resulting in pore wall roughness, affecting the hole, electroplating copper and other quality problems.
Therefore, the majority of Shenzhen circuit board manufacturers use three (or step) pulse launchers to complete the processing, and three laser pulse energy density will be followed by weakening (or halved), that is, step-by-step pulse.
Carbon dioxide laser processing materials used
In recent years, widely used in circuit board factory carbon dioxide laser etching resin coated copper foil RCC} material, a representative manufacturer, mainly in Japan, China's Health Science and Technology has been produced in 2002.
There are many factors that affect the hole formation of carbon dioxide laser. At present, the technology of PCB hole drilling with carbon dioxide laser has reached a mature stage. However, the main factors that affect the productivity of carbon dioxide laser hole and the hole quality are PCB substrate (or medium Layer material), carbon dioxide laser energy density plus method, hole depth and size.