Cutting flexible circuits boards with UV lasers is quickly becoming the method of choice in the industry, surpassing more traditional mechanical approaches.
As we know, the production of printed circuit boards (PCBs) is an extremely complex process that requires specialized equipment and engineering knowledge. The advent of lasers is one of the most recent technological advances that has streamlined the key aspects of PCB manufacture.
The production of flexible printed circuit boards demands the use of a variety of materials. The selection of these materials is based on their electrical performance to assure both mechanical and electrical dependability. Therefore, FPC PCB laser Cut plays an important function in PCB fabrication.
What Is Laser Cutting ?
The term “laser cutting” refers to a technique that creates a cut edge by vaporizing material with the aid of a laser. In the past, it was utilized for manufacturing purposes in industrial settings; however, today, it is utilized in educational institutions, small enterprises, architectural projects, and by hobbyists. The output of a high-power laser is most typically directed through optics in the course of the laser cutting process.
In order to focus the laser beam on the target material, the CNC (computer numerical control) and laser optics are utilized. When cutting materials with a commercial laser, the laser will employ a motion control system to follow a CNC or G-code of the pattern that needs to be cut into the material. After the focused laser beam is directed at the material, the substance will either melt, burn, evaporate away, or be blown away by a jet of gas, leaving behind an edge with a surface finish of a high quality.
Laser Cutting: History
The first manufacturing laser cutting equipment was used to drill holes in diamond dies in 1965. The Western Electric Engineering Research Center created this machine. The British invented laser-assisted oxygen jet cutting for metals in 1967. This technology was first mass-produced in the early 1970s, when it was used to cut titanium for use in the aerospace industry.
At the same time, CO2 lasers were adapted to cut non-metallic materials, such as textiles, due to their inability to overcome the heat conductivity of metals at the time.
Flexible and Rigid-flex PCB Profiling: Laser Cut
Because of the proliferation of flexible PCB materials, the process of depaneling individual circuit boards from production panels has historically been fraught with difficulties. Mechanical profiling techniques such as V-scoring and routing can readily damage sensitive and thin substrates, which creates challenges for PCB manufacturers who profile flex and rigid-flex boards.
JarnisTech, a reputable producer of flex and flex-rigid printed circuit boards in China, has been using the laser cut method for a significant number of years. The impacts of mechanical stress that occur during profiling, such as burring, distortion, and damage to flexible circuits, can be eliminated with the use of laser cutting.
Flexible Circuit Board Use Laser Cutting: What Is Benefitc ?
● The cutting of flexible circuit board materials is the origin and also the strong suite of the laser as a depaneling tool. With the laser depaneling technique, it is possible to obtain high-quality cutting edges and efficient cutting speeds.
● Flexible PCBs of a wide range of thicknesses and materials can be detached without difficulty. This includes copper layers and flexible, semi-flexible, rigid-flex, and HDI rigid-flex materials, among others. Ablation of materials, such as in the case of cover layers, can also be accomplished incomparably using the laser. With no other tool is it possible to take into account the different requirements of the materials so readily, while also processing the substrate with great care and precision.
● On neither the laser entrance side nor the laser departure side does the tool leave any residues that are capable of having a detrimental effect on the overall quality of the substrate or the printed circuit board as a whole. Particularly with the CleanCut technology developed by JarnisTech, a cut edge that is free of carbonization and, as a result, an absolute maximum in terms of technical cleanliness can be guaranteed.
● When compared to alternative techniques, the yield of circuit board fabrication can be greatly boosted with this method, as can the reliability of the assembled boards once they have been deployed in the field.
Laser Cut Flexible Materials
When it comes to the fabrication of flex PCBs and rigid-flex PCBs, laser cutting is the most cost-effective and time-efficient method, especially for prototypes and small batches. This will help you save money and speed up the turnaround time. In the manufacture of modest quantities of FPCs, laser cutting is the most common method for slitting flexible materials such as, the following materials including:
● EMI shielding film
● 3M/Tesa PSA (Pressure Sensitive Adhesive)
● Coverlay: used for covering flexible copper layers.
● PI stiffeners: mechanical support or heat dissipation element.
● Adhesive: used for bonding multi-layer FCCL, PI stiffener and top side of coverlay.
● FCCL: Polyester (PET) based flexible copper clad laminate (FCCL) and Polyimide (PI, also known as Kapton)
Laser cutting or laser drilling plays an important part in the manufacturing of Dual-Access Flex Circuits. This type of depth-controlled drilling is also referred to as Laser Depth Control. Copper will not be harmed by the laser beam because it is only able to ablate flexible dielectric materials.
Laser Cut Accuracy for Flex PCB Depaneling: How to Improve ?
For the purpose of minimizing waste and damage, when depaneling Flex PCBs, the accuracy of the cut is crucial. Making sure that the laser is precisely aligned with the panel’s features and components will ensure that cuts are placed consistently.
A vision system identifies specific panel features and modifies the cut path to ensure that the circuits are aligned precisely with the cuts.
Meeting Trends of Flex PCB Laser Cut
● Because of advances in UV laser technology, designers of flex circuits are now free to experiment with the use of designs that are both complex and arbitrary. Traditional circuit shapes and sizes can be put to the test now that innovation is no longer hampered by the constraints of technological restrictions.
● As UV laser systems are capable of producing precise and clean cuts, the components of a circuit can be positioned closer to one another and to the circuit’s edge without compromising the integrity of either. In addition, UV laser cutting guarantees that the mounting density is increased to its full potential and that the bridging space between circuits is reduced, resulting in panels that are filled to their maximum capacity.
● Since the invention of UV laser cutting, it has been far less difficult to select the most appropriate method for flex depaneling. UV laser cutting is the best option for people who are seeking for flex depaneling solutions since not only can it be used for a wide variety of applications, but it also reduces the amount of stress that is put on the board, has thin cut widths, and is as exact as surgical cutting.
When Choose Laser Cut ?
When manufacturing flexible circuits for customers, JarnisTech always considers competitive price. Prior to investing in pricey punching dies, laser-cutting is ideal for achieving precise tolerances. Examples include compact form-fit devices and ZIF connectors. Laser cut profiling is an excellent method for producing pattern-routed b-stage adhesive. The laser method can provide a “cured” edge along the rout path of the adhesive in order to limit the amount of resin squeeze-out produced by the press lamination process.
What Format File Is Required During Laser Cutting Process ?
In laser cut processing, although most PCB file types can be used, Gerber, Excellon, DXF, or other 2D formats are the file types that are favored. This is despite the fact that most file types can be used. But, Jarnistech will perform the necessary scaling or offsets to meet production panel sizes, therefore in the majority of instances, non-scaled data is required.
Conclusion
When it comes to the production of printed circuit boards, laser cutters are an essential and highly specialized piece of equipment to have. PCBs can be drilled, cut, marked, and sintered using the equipment in this category; among their other applications, these machines serve a variety of functions. Because of its high level of precision, this types of machinery is widely regarded as the superior choice among the options available to manufacturers of rigid and flexible printed circuit boards. Lasers cut also leverage the no-contact technique, making it easy to use in the fabrication of flex PCBs and rigid PCBs.
