Frequently Asked Questions about Laser Drilling PCB

What is laser drilling?

In laser drilling, short laser pulses with high power density are emitted to the workpiece. The material is removed (ablated) by the energy of the laser radiation in various ways - depending on the pulse duration: it is melted, vaporized or ionized. The greater the energy of the pulse, the more material is ablated. The duration of the individual pulses is decisive for the quality of the drilled hole. Shorter pulse durations significantly reduce the thermal load on the workpiece.

During ablation, the volume of the material in the drilled hole suddenly increases, generating high pressure. This pressure forces the molten material out of the drilled hole in a very short time without leaving any residue.

What is impact drilling?

In impact drilling, the laser radiation does not hit the material in a long single pulse, but in several short pulses. Each time, some of the material is melted and evaporated. The evaporated material pulls the molten material out of the drill hole. Impact drilling can achieve a higher maximum drilling depth, i.e. up to 100 mm, compared to 2 mm for the single-pulse method. The process is also suitable for machining extremely hard materials.

What is trephine?

When drilling, through-holes ("bores") are first drilled using the percussion method. These are then widened to the desired hole diameter by ring drilling. For this purpose, a rotational movement of the laser beam relative to the workpiece is generated. The advantage of this method is that the formation of a melt layer on the hole wall is reduced. This makes the process particularly suitable for the production of sensitive workpieces.

What are the advantages of laser drilling compared to conventional methods?

For mechanical drilling, the hole is processed using a drilling tool with a defined cutting edge. The resulting chips can soil or even damage the workpiece. The diameter and quality of the hole are related to the diameter and wear of the drilling tool, so different diameters require different drilling tools. This requires tool changes that do not add value and the tool costs are high due to the limited service life. There is also the risk of the drill breaking and the workpiece being destroyed during use,

Laser-based drilling saves the long setup times for changing drilling tools and there is no wear on the drill. The ablation of the laser process gives you residue-free drilling as well as chip-free and dust-free processing. The process stability of the laser machine is very high, because our fully calibrated machines achieve absolutely stable process conditions for many years, which can also be directly reproduced on new machines. For example, processes in Europe can be certified accordingly and transferred directly to a production facility at the outsourcing location at the push of a button.

What applications are suitable for laser drilling?

Leiser has products and solutions with the following process capabilities in its portfolio:
Drilling, drilling (blind vias), removal of overburden material.

Our laser drilling systems are highly flexible and are especially suitable for small batches!

Is it worth investing in a laser drilling system?

Yes, especially since the subsequent costs of conventional drills and tools (wear, setup times, material waste, etc.) are eliminated. Laser drilling systems are wear-free, take up fewer man-hours and increase your added value. The setup times are a clear competitive advantage in your internal processes. The price/performance ratio of today's laser drills is 10 times that of 10 years ago. This also makes these systems economical for small and medium-sized companies.

How small can the laser hole be?

Typical diameters for laser drilling with ultrashort pulse lasers are usually 20-500渭m. Depending on the requirements and the laser drilling process, our systems can also achieve drilling diameters of up to 10渭m.