In January we made one of our largest investments in a single piece of machinery when we installed a Ledia V5 direct imaging system from Japanese image-processing company Screen.
Our commitment to the European engineering design community demands continuous investment in new production technology. When you need a new PCB technology we must have the necessary manufacturing processes in place. For example, fine-pitched components (BGAs etc.) require increasingly fine soldermask dams between pads to minimize the risk of solder shorts. The Ledia V5 allows us to offer finer dams than are possible with conventional imaging technology.
The Ledia V5 will also give us
- shorter process times and more capacity. That way we keep fast deliveries on time.
- more pooling service opportunities to help you keep your costs down.
What is Direct Imaging?
Traditional PCB imaging systems expose photosensitive etch and plating resists and soldermask inks using film-based phototools. Direct imaging systems cut out the phototool and use scanning technology to “write” the image directly onto the resist.
The success of the new technology can be seen from equipment sales within the PCB industry: since 2010 Direct Imaging systems have outsold the traditional phototool-based exposure systems by 3 to 1.
What are the benefits of the Ledia V5?
We will use Ledia for inner layers, fine-line outer layers and tight-toleranced soldermasks.
The Ledia V5 direct imaging system installed in the yellow room in our plant in Eger.
1. Higher quality imaging, especially of fine-line PCBs
1.1. More accurate imaging of fine tracks and fine features.
The Ledia V5 uses a more coherent light source than conventional exposure systems. The LEDs can be fine-tuned to give a more precise polymerization of photosensitive resists and inks. Using Ledia V5 we can image fine lines and features on PCBs more accurately and more reliably than before.
1.2. Better registration allows tighter tolerances on outer layers and soldermasks.
Conventional exposure systems use fixed phototools. Designers must reduce packing densities on multilayer PCBs to accommodate the process tolerances on the phototool as well as the tolerances required by PCB manufacture. Multilayer bonding in particular can introduce linear and non-linear distortions in production panels. These distortions are difficult to predict as they depend to a large extent on the copper layout itself.
Direct Imaging brings two advantages: it eliminates the tolerances required by the phototool, and it allows dynamic registration on each production panel. Thus the Ledia V5 automatically aligns the image to each drilled panel, and then uses fiducials to compensate the image “on-the-fly” for any linear or non-linear distortion in the panel. Even on large pooling panels fine-line circuits can be registered individually without loss of throughput. Image compensation allows successful imaging of tighter-toleranced PCBs with higher packing densities.
2. Tighter toleranced soldermasks for fine-pitched components (BGAs etc.)
Higher quality imaging and more precise registration means that we can image soldermasks with tighter tolerances.
- designs with higher packing densities. Smaller soldermask windows allow smaller gaps between copper pads and adjacent tracks
- more reliable soldering at board assembly. Ledia can image finer soldermask dams between fine-pitch pads to prevent solder shorts.
3. More plant capacity for faster and more reliable deliveries.
Direct imaging cuts out the process steps needed to plot, inspect and register phototools as well as to register them onto the exposure units. As we specialize in prototype and small batch orders we need to process tens of thousands of phototools annually (in 2014 at our Eger plant we used 36,000 films for imaging and 25,000 films for solder mask). Reducing these figures, perhaps by as much as two-thirds, will shorten our production cycle and increase plant capacity, meaning faster and more reliable deliveries, especially for 2 – 3 day jobs.
4. Minimum disruption to production and to processes.
The first Direct Imaging systems used UV lasers, but, as its name suggests, the Ledia 5V uses high-intensity LEDs. The peak efficiency of a UV laser falls within a very narrow frequency band, so DI systems using UV lasers need special resists. The Ledia V5’s LEDs have a broader frequency range so that we can continue to use our existing resists and soldermask inks. This makes Ledia 5V a “drop-in” upgrade to our existing imaging processes. So no time lost evaluating and approving new processes; there is minimum disruption to production – and our customers don’t need to re-qualify our soldermasks.