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 so that you can increase throughput of PCB Depanel as circuit board sizes reduced. At CMS Laser, our depaneling process has the main benefit of speed, pin-point accuracy, no tooling cost or wear, no part induced stress, with no cutting oils or any other waste.
Demand Driven by Size
As technology consistently evolve, the gadgets we use become a little more advanced and quite often decrease in size. This reduced size requires smaller PCBs. Without set standard for PCBs, every board is designed for a certain item. Therefore, this process for depaneling separate boards from a multi-image board is unique. Production factors including stress, precision and cleanliness are paramount to keeping board defects as low as possible.
PCBs are generally manufactured in large panels containing multiple boards at the same time, but can also be produced as single units if necessary. The depaneling of PCBs process could be fully automatic, manual, or semi-automatic. There are many methods used, including laser PCB depaneling, within the electronics industry. Let’s examine whatever they are:
The punching method is the method of singular PCB Depaneling Router being punched out of the panel with the use of an exclusive fixture. The punching fixture has sharp blades on one part and supports on the other. An alternative die is necessary for each and every board and dies must frequently be replaced to keep up sharpness. Even though production rates are 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 of the panel are scored to your depth of approximately 30 percent of the board’s thickness. Once boards have already been populated, they may be manually broken out of the panel. You will find a strain put on the boards that can damage a few of the components or crack the solder joints, especially those close to the edge of the board.
Wheel Cutting/ Pizza Cutter:
The “pizza cutter” strategy is a manual alternative to breaking the net after V-scoring to reduce the rest of the web. Accuracy is essential, since the V-score and cutter wheels must be carefully aligned. There is a slight amount of stress aboard which may affect some components.
Laser depaneling can be carried out on boards requiring high tolerances. Depaneling occurs without physical contact, without mechanical stress, and it is adaptable to slice requirements by way of a computer controlled process. Laser depaneling is acceptable for installation in surface mount technology (SMT) lines or with board unloaders/loaders for standalone operation.
Most PCBs are routed leaving the individual circuits connected to the panel frame by narrow tabs which can be subsequently broken or snapped to singulate the circuits. Routing may take up hbrerp panel area as a result of wide kerf width of a physical bit.
Laser routing offers a complete software-controlled process without reliance upon any mechanical dies or blades. Laser routing can cut any shape path including curves and sharp corners. The cut kerf width could be lower than 20 microns, providing exceptional accuracy.
Laser routing can be performed using either:
High-power CO2 laser (~10µm wavelength)
The CO2 laser can thermally cut through FR4, glass fibers as well as other rigid and flex circuit substrates at comparatively high-speed though with noticeable heat effect on the fringe of the cut for many substrates.
Solid-state UV laser (355nm wavelength).
The UV laser, having a considerably smaller focused spot size, ablates the panel material with significantly less heat along with a narrower kerf width. However, due to lower power levels, the cutting speed is much slower compared to CO2 laser and the cost/watt of UV lasers is higher than that of CO2
Generally speaking, companies that are understanding of char and fine debris across the cut line will employ the UV laser while users who clean the circuits after singulation can be helped by the higher speed in the CO2 laser.
Laser systems for depaneling play an essential role later on from the PCB manufacturing industry. As demand for Laser Depaneling still parallel technology trends, including wearables and Internet of Things (IoT) devices, the necessity for systems that increase production line speed and lower costs for manufacturer will also still rise.
Within our Applications Development Lab, we assist each client to ascertain the ideal laser and optics configuration for any manufacturing process.
Within this three-part series on PCB depaneling, upcoming posts will discuss the huge benefits and challenges of PCB depaneling, together with the evolution of PCB depaneling with laser systems.