PCB (printed circuit board) depaneling, also called singulation, is the method of removing numerous smaller, individual PCBs from the larger multi-PCB panel produced during manufacturing. The depaneling process was made to be able to increase throughput of PCB Router as circuit board sizes reduced. At CMS Laser, our depaneling process has the benefit of speed, pin-point accuracy, no tooling cost or wear, no part induced stress, and no cutting oils or any other waste.
Demand Driven by Size
As technology will continue to evolve, the gadgets we use become more advanced and often reduction in size. This reduced size requires smaller PCBs. Without set standard for PCBs, every board is ideal for a specific item. Therefore, the procedure for depaneling separate boards coming from a multi-image board is exclusive. Production factors including stress, precision and cleanliness are paramount to keeping board defects as low as possible.
PCBs are generally created in large panels containing multiple boards at the same time, but may also be produced as single units if necessary. The depaneling of PCBs process could be fully automatic, manual, or semi-automatic. There are several methods used, including laser PCB depaneling, in the electronics industry. Let’s examine the things they are:
The punching method is the method of singular Inline PCB Router being punched out from the panel with the use of a special fixture. The punching fixture has sharp blades on a single part and supports on the other. An alternative die is necessary for each and every board and dies must frequently get replaced to keep up sharpness. Although the production rate is high, the custom-designed fixtures and blades demand a reoccurring cost.
Boards are scored over the cut line on sides to minimize overall board thickness. PCBs are subsequently broken out from the panel. Each side from the panel are scored to some depth of about 30 percent from the board’s thickness. Once boards have already been populated, they can be manually broken out of the panel. There is a strain put on the boards that will damage a number of the components or crack the solder joints, especially those near to the side of the board.
Wheel Cutting/ Pizza Cutter:
The “pizza cutter” technique is a manual alternative to breaking the web after V-scoring to reduce the rest of the web. Accuracy is critical, as the V-score and cutter wheels should be carefully aligned. You will find a slight degree of stress aboard which may affect some components.
Laser depaneling can be performed on boards requiring high tolerances. Depaneling occurs without physical contact, without any mechanical stress, and is also adaptable to slice requirements by way of a computer controlled process. Laser depaneling is suitable for installation in surface mount technology (SMT) lines or with board unloaders/loaders for standalone operation.
Most PCBs are routed leaving the person circuits linked to the panel frame by narrow tabs which are subsequently broken or snapped to singulate the circuits. Routing will take up hbrerp panel area because of wide kerf width of a physical bit.
Laser routing provides a complete software-controlled process without reliance on any mechanical dies or blades. Laser routing can cut any shape path including curves and sharp corners. The cut kerf width may be less than 20 microns, providing exceptional accuracy.
Laser routing can be executed using either:
High-power CO2 laser (~10µm wavelength)
The CO2 laser can thermally cut through FR4, glass fibers and other rigid and flex circuit substrates at comparatively high-speed but with noticeable heat effect on the side of the cut for many substrates.
Solid-state UV laser (355nm wavelength).
The UV laser, using a considerably smaller focused spot size, ablates the panel material with considerably less heat as well as a narrower kerf width. However, as a result of lower power levels, the cutting speed is much slower compared to the CO2 laser and also the cost/watt of UV lasers is higher compared to CO2
Generally, firms that are sensitive to char and fine debris along the cut line will employ the UV laser while users who clean the circuits after singulation can be helped by the greater speed of the CO2 laser.
Laser systems for depaneling play an integral role later on of the PCB manufacturing industry. As demand for Inline PCB Laser Depaneling carry on and parallel technology trends, like wearables and Internet of Things (IoT) devices, the necessity for systems that increase production line speed and lower costs for manufacturer will also carry on and rise.
Inside our Applications Development Lab, we work together with each client to determine the ideal laser and optics configuration to get a manufacturing process.
In this particular three-part series on PCB depaneling, upcoming posts will discuss the benefits and challenges of PCB depaneling, combined with the evolution of PCB depaneling with laser systems.