INTRODUCTION
There was a time when IT manufacturing plants revolved around mechanics and hardware assembly. While the software side of things could do some amazing stuff in virtual land, the assembly of servers, PCs, and circuit boards was still locked well into the basic mechanics. Adhesion and assembly were applied through screws, solder, drilling, cutting, puzzle locks, hedging, and even carpentry principles applied to metal and plastic. It’s a bit ironic how, for so many years, the very tools industries have used for technological advancement have still relied on assembly methods applied with tools created centuries ago.
However, there is a transformation happening in the world of circuit board manufacturing, and much of it has to do with the need to have components that do more with less material. That means circuit boards themselves have to be lightweight, flexible, made of thinner material, and able to perform electronic traffic activity at higher levels of performance, i.e. more circuits packed onto a smaller footprint for greater output.
These drivers are revolutionizing the circuit board field, which, in turn, has created new demand for better assembly and construction methods.Common concerns around the assembly of a circuit board involve:
The days of old square generic boards are ending quickly. Think about how thin modern smartphones and tablets are today; would they be able to fit the clunky, generic circuit boards of just five years ago?
Absolutely not.
So now that the demand is there, manufacturers have realized that their tools are out of date. The softer, thinner, and more pliant materials used for today’s modern circuit boards can’t handle the brutish cutting and router punching used on old thick FR4 boards. Think about a thin piece of plastic.
When a pressure point is applied, does it create a perfect hole? No, it deforms, causing the material to wrinkle wider than the point of impact desired. This is one of the many problems manufacturers are facing with their old machines. Here are five reasons why UV laser cutting is the ideal, advanced method to solve the modern board tooling challenge.
REASON #1 >> No Stress and Cleaner Cutting
As noted earlier, pressure stress is a big problem with modern circuit boards that are far thinner and less dense. Both Printed Circuit Boards (PCBs) and Flexible Printed Circuit Boards (FPCs) are in high demand, but can be easily damaged by common cutting, drilling, and the depaneling processes.
A router is a standard tool used for cutting grooves, holes, and channels. Using a router could cause deformation with the softer board materials versus old, harder and thicker circuit boards. Other forms of stress caused by routing include:
A router uses a bit which will vibrate the entire PCB panel when cutting. This can cause issues with components and delamination on the edge because of the friction it uses to cut through a board. Damage can occur when slicing out specific size circuit board segments, causing intense vibration as well as a lot of dust debris that can cover the PCB. Microdust can cause short-circuiting between components if not cleaned off properly.
Cutting creates heat at the friction point, which causes modern board material to melt and warp noticeably. Even thicker boards suffer similar damage. Melted slag accumulates at the edge, requiring additional cleaning and removal to make sure the slag doesn’t interfere with the circuitry operation. Other cutting options that also have drawbacks:
All the typical methods of destructive shaping, burring, sanding, drilling and cutting require some form of underlay material to prevent the tool from cutting in to the machine’s working table. Some tooling changes have tried to focus on stabilization and reducing the effects of cutting and routing stress by clamping down on the affected area of the board. While cushion pads and stabilization will help, they do not solve accuracy problem.
These methods are simply too blunt and cannot offer the finesse needed for the high-end technology boards of today. Eventually, factories and companies will realize they are in a losing the battle by trying to hold onto dated tools instead of looking into new approaches.
Ultraviolet (UV) laser cutting solves all the above assembly and tooling challenges. UV lasers do not put any stress on the PCB (Printed Circuit Boards) panel during the depaneling or drilling process, which is especially important when comparing with mechanical methods. The various stress factors caused by traditional mechanical tooling are eliminated. Depaneling with an UV laser will operate with:
UV laser cutting solves most all of the problems manufacturers face with modern FPCs and PCBs.
REASON #2 >> Minimal Debris
As noted earlier, traditional cutting methods create significant debris that then has to be vacuumed off the board as well as the manufacturing area. High heat melting creates burn off, carbonization, and slag. A router has the worst track record in this area, as it leaves dust particles all over the panel and manufacturing floor which can damage sensitive components and require additional cleaning, not to mention the inherent health risks of breathing fiberglass dust.
A UV laser ablates the material turning it into finer particles, which get extracted by the exhaust system. Any remaining debris would be minimal and not damaging to the sensitive components.
REASON #3 >> Superior Accuracy & Precision
The detail and accuracy of UV lasers are utterly amazing. The results far exceed the quality levels of mechanical cutting and routing, making traditional board modification tooling obsolete. And as FPCs and PCBs continue to shrink, accuracy and micro-cutting is becoming a basic bread-and-butter manufacturing necessity.
Heat is a major problem with conventional laser cutting because a laser typically involves a highly focused beam of heat. In short, a regular laser can make board material practically useless with one bad cut. Not to mention, conventional laser cutting is often jagged and uneven. To the regular eye it may seem like a good separation, but at the circuitry level, the results are about as uneven as driving on a pothole filled road.
UV laser cutting reduces the heat point tremendously. In fact, it’s often termed a “cold” separation because the temperature level is exponentially low compared to a normal laser cut effect.
The result is a very straight, extremely fine cut that works at a very microscopic level—perfect for compact board products and small, unique fitting shapes and contours.
REASON #4>> Material Versatility
The beauty of UV laser depaneling is that it can handle so many materials. Unlike routing and drilling, or gas cutting, UV laser is entirely flexible and perfect for materials that can be damaged from high temperatures. It can process all standard PCB materials such as FR4, Polyimide, Rogers, LTCC, fired ceramics and various metals.
Where a hot friction blade or a CO2 laser cut would burn hot, UV laser cutting can separate like a scalpel with minimal heat effect. There is also no radiant heat, so there is no surround field damage from the point of application. Regardless of whether a material is very dense or highly fragile, UV lasers will solve this problem while retaining accuracy, effectiveness, and efficiency.
REASON #5>> Application Versatility
UV lasers are abundantly flexible for various needs. Cutting and drilling are not the only uses for this tool.
UV lasers can perform:
Intricacy in a number of different manufacturing arenas are now possible with UV lasers. Again, small is the new “in-demand” expectation, and UV laser production allows unique, custom shaping and sizing to be possible not just as a one-off, but as a mass production high quantity output tool. The result is a level of manufacturing that marries high capacity assembly output and yield, with extreme detail cutting and edging. Previously, this kind of quality required very expensive hand-driven equipment, driving up pricing to customers.
On the board design side of things, creators and designers can begin to play with shapes, forms, and designs previously not possible due to tooling limitations. UV laser application makes the generic square circuit board from yesteryear a has-been.
CONCLUSION
Given all the above, when you look at your production floor, what do you see regarding capabilities? Imagine what it could be with a UV laser system?
Think about this question in terms of your current market and the potential to enter into multiple new markets. A UV laser system can solve current issues and increase yield.
Want to learn more about UV lasers and how they can help you win new business? Click here to set up an informational call about LPKF and UV lasers.
