PCB (printed circuit board) depaneling, also referred to as singulation, is the process of removing numerous smaller, individual PCBs from the larger multi-PCB panel produced during manufacturing. The depaneling process was created so that you can increase throughput of PCB Depanel 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 some other waste.
Demand Driven by Size
As technology will continue to evolve, the gadgets we use be a little more advanced and frequently reduction in size. This reduced size requires smaller PCBs. Without set standard for PCBs, every board is made for a particular item. Therefore, this process 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 to a minimum.
PCBs are usually produced in large panels containing multiple boards at any given time, but can be produced as single units if need be. The depaneling of PCBs process could be fully automatic, manual, or semi-automatic. There are numerous methods used, including laser PCB depaneling, inside the electronics industry. Let’s examine whatever they are:
The punching method is the process of singular PCB Depaneling Router being punched out of the panel with the use of a special fixture. The punching fixture has sharp blades using one part and supports on the other. An alternative die is required for every board and dies must frequently be replaced to maintain sharpness. Although the production rates are high, the custom-designed fixtures and blades demand a reoccurring cost.
Boards are scored across the cut line on sides to reduce overall board thickness. PCBs are subsequently broken out of the panel. Each side in the panel are scored to your depth of approximately 30 percent from the board’s thickness. Once boards have already been populated, they could be manually broken out of the panel. There is a strain put on the boards that can damage a few of the components or crack the solder joints, in particular those near the side of the board.
Wheel Cutting/ Pizza Cutter:
The “pizza cutter” method is a manual option to breaking the web after V-scoring to cut the other web. Accuracy is critical, because the V-score and cutter wheels must be carefully aligned. There is a slight level of stress on board which could affect some components.
Laser depaneling can be performed on boards requiring high tolerances. Depaneling occurs without physical contact, without mechanical stress, and it is adaptable to reduce requirements via 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 person circuits attached to the panel frame by narrow tabs which can be subsequently broken or snapped to singulate the circuits. Routing will take up hbrerp panel area due to wide kerf width of any physical bit.
Laser routing supplies 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 can be under 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 and other rigid and flex circuit substrates at comparatively high speed but with noticeable heat effect on the edge of the cut for most substrates.
Solid-state UV laser (355nm wavelength).
The UV laser, having a considerably smaller focused spot size, ablates the panel material with considerably less heat along with a narrower kerf width. However, as a result of lower power levels, the cutting speed is much slower compared to CO2 laser as well as the cost/watt of UV lasers is higher than that of CO2
Generally speaking, firms that are sensitive to char and fine debris over the cut line will employ the UV laser while users who clean the circuits after singulation can benefit from the higher speed of the CO2 laser.
Laser systems for depaneling play an essential role down the road of the PCB manufacturing industry. As interest in Laser Depaneling carry on and parallel technology trends, such as wearables and Internet of Things (IoT) devices, the necessity for systems that increase production line speed and reduce costs for manufacturer may also continue to rise.
In our Applications Development Lab, we work together with each client to determine the ideal laser and optics configuration for any manufacturing process.
Within this three-part series on PCB depaneling, upcoming posts will discuss the advantages and challenges of PCB depaneling, together with the evolution of PCB depaneling with laser systems.