Think of all the devices we use in a day: our phones, our TVs, the computers we work on, the systems in our cars deploying the airbags or medical components that save lives. All of these technologies have one thing in common – they all have printed circuit boards (PCBs) hidden somewhere inside the design. Those PCBs must be manufactured to precise specifications to ensure they work at top capacity, which requires PCB depaneling.
What is PCB depaneling?
PCB depaneling is the process of removing numerous smaller, individual boards from a larger panel during manufacturing.
PCBs are usually manufactured in large panels with multiple boards, but can also be produced as single units. The depaneling process can be fully automatic, semi-automatic, or manual. This brings lower throughput, along with eliminating the added cost of tooling and waste removal associated with mechanical methods.
Many methods can be used for PCB depaneling depending on the application and materials. The most common today, because of the delicate components, soldered connections, and fragile substrates, is the laser process.
The laser process is ideal for many reasons. Due to minimal space between the boards, there is more value per panel. In addition, components can be placed adjacent to each other to minimize unnecessary bulk and weight. Understanding the effects of laser energy to the material allows the manufacturer to take full advantage of the technology without unwanted side effects.
Why are PCBs Important?
Without PCBs, recent electronic designs would not have been possible. These marvels of technology support and connect all the electronic components needed to make the magic happen inside a device or machine.
The miniature design of various devices that require printed circuit boards is pushing the limits of electrical performance.
With continued advances in integrated circuit (IC) fabrication, the number and density of connections to interface the devices continue to rise. In order to further aid in the increased output of PCBs while still maintaining a small size, depaneling was created.
A-Laser depaneling is done with speed, pin-point accuracy, no tooling cost or wear, no part induced stress, and no cutting oils or other waste. A non-contact depaneling method using lasers provides a highly precise singulation without any risk of harming material, regardless of substrate.
As the technology community continues to innovate and create smaller and more advanced devices, A-Laser offers the latest in precision part manufacturing to meet this demand.
It is imperative to understand the various depaneling methods, since each application’s requirements affect the choice of method used. Some depaneling methods are useful only in low cost, minimal quality applications, or where the board is rectangular in shape. Potential damage to the board is also an important consideration.
Typical Depaneling Methods
This process requires a different die for each new circuit board. The punching fixture has sharp blades on one part and supports on the other.
It also uses either a shearing or crushing method, which can deform the board. Sharp die edges are imperative to minimize damage.
Board thickness is reduced by boards being scored along the cut line on both sides. Both sides of the panel are scored to a depth of about 30% of the board’s thickness. PCBs are then broken out of the panel.
Wheel Cutting/ Pizza Cutter:
This is a manual alternative to breaking the web after V-scoring to cut the remaining web. This method requires careful alignment between the V-score and the cutter wheels to reduce stress to some components.
A single routing saw blade is typically used to cut the panel from either the top or the bottom.
This technology has not yet fully been explored but the cutting is done with a high-speed stream of slurry.
Slurry is a water mixed with an abrasive, and then cleaning is done to remove the abrasive portion after the method is employed.
Most PCBs are routed, which leaves the individual circuits connected to the panel frame by narrow tabs. The tabs are broken or snapped to singulate the circuits.
No mechanical dies or blades are needed for this method, which is completely software-controlled.
Any shape path, including curves and sharp corners, can be completed with this method, which also provides an unparalleled space advantage.
What the Numbers Say:
In every one of the above methods, except in laser routing, some degree of mechanical stress is exerted on the boards. This inflicted stress can lead to delamination or cause a space to develop.
These methods also require that the final connections between the boards and panel be removed. The bending stress can damage components close to the areas of necessary removal.
Laser routing is the most recent tool in delaminating flex and rigid boards.
Laser routing offers all of the following benefits:
A knowledgeable and experienced operator can select the optimum settings to guarantee a clean cut with no burn marks. Material type, thickness, and condition are all factors that will be considered and will determine the speed (and consequently will affect the temperature) of the laser.
An exhaust or filter system removes any expelled material during the laser process.
If the application does produce an extremely small particle residue, compressed air or a smooth tissue can be used.
Since there is no contact with the panel during cutting, lasers allow all most or all depaneling to be done after assembly and soldering. This allows for the avoidance of any bending or pulling of the board and therefore no stress is applied and no damage occurs.
As the technology community continues to innovate and create smaller and more advanced devices, lasers offer the latest in precision part manufacturing to meet this demand. The reduced size and intricate design of new technology requires smaller PCBs. Since there is no standard set for PCBs, every board is design-specific. This results in the need for employing multiple depaneling methods specific to the design.
Laser depaneling has significant economic advantages and therefore is often the top choice in today’s technology-driven depaneling methods. The reduced stress and potential damage placed on materials using laser depaneling greatly increase long term reliability, and lower temperatures during cutting along with no carbonization are huge benefits as well.
A-Laser has years of experience meeting our customer’s needs in depaneling. The key is communication, so we take the extra steps to be certain our customers receive the best laser cut product available.
We always strive to outperform and raise the bar for laser cutting, laser ablation routing, laser micromachining and post process services in today’s market.