What is laser ablation?

Laser ablation describes the controlled removal of material using high-energy laser pulses. These short light pulses strike the surface of a workpiece and heat it to such an extent that the material evaporates from the top layer or directly transitions to a gaseous state. The surrounding material remains virtually unaffected.

Range of applications and technical characteristics of laser ablation

Laser ablation is characterized by high precision and broad material applicability. The process is contactless and suitable for various materials, including metals, plastics, glass, ceramics, and even fabrics. In industry, laser ablation is often used to create fine structures, modify surfaces in a targeted manner, or selectively remove coatings.

Advantages at a glance

Laser ablation is particularly advantageous due to its wear-free, precise, and reproducible process. There is no mechanical stress on the component, as the material removal is purely optical. Tools do not need to be resharpened or replaced, which reduces maintenance. In addition, suitable extraction technology minimizes residues, contributing to a clean machining process.

Technical limitations

Despite its strengths, laser ablation has its limitations in certain applications. Larger volumes of material or deeper layers can often only be removed slowly. In addition, the local heat effect can lead to changes in the edge area of sensitive materials. The high investment costs and the need for specific expertise in setup and process monitoring must also be taken into account.

Laser ablation in the application context of photonics systems

Photonics Systems develops high-precision laser systems for industrial applications in which laser ablation plays a central role. Typical areas of application include microdrilling, gentle cleaning of sensitive surfaces, and structuring and marking of materials, particularly in semiconductor and electronics manufacturing. For these requirements, Photonics offers specialized machine platforms in which laser ablation is specifically integrated. These include the DR20x0 and DR30x0 series for precise drilling and routing of printed circuit boards, and the CR20x0 series for processing ceramic substrates.

How does laser ablation work?

The effect of laser ablation is based on deliberately exceeding the so-called ablation threshold of a material. This describes the minimum energy required to alter the material using laser radiation. If this threshold is reached or exceeded, the material vaporizes in a controlled manner. If the energy remains below this threshold, the surface merely heats up slightly.

Use of different laser types

Different types of lasers are used depending on the application.

Ultra-short pulse laser

Nanosecond lasers with a green wavelength of 532 nanometers significantly improve absorption in materials such as copper compared to conventional CO₂ lasers, resulting in increased efficiency. Especially in dielectric materials, multiphoton absorption promotes cutting quality and enables more precise results. Green nanosecond lasers offer a good balance between high performance and comparatively moderate operating costs.

Nanosecond laser

Nanosecond lasers with a green wavelength of 532 nanometers significantly improve absorption in materials such as copper compared to conventional CO₂ lasers, resulting in increased efficiency. Especially in dielectric materials, multiphoton absorption promotes cutting quality and enables more precise results. Green nanosecond lasers offer a good balance between high performance and comparatively moderate operating costs.

Precise machining without material stress

Only a small area on the surface is heated for an extremely short time. The rest of the material remains cool, making laser ablation ideal for precise surface treatment without mechanical or thermal stress.

Typical applications of laser ablation

Laser ablation is used in numerous industries, namely wherever controlled material removal and maximum precision are required. Its flexible adaptation to different materials and geometries offers a wide range of applications.

Material marking and engraving

Laser ablation is used in the automotive, aviation, and electronics industries to mark components permanently and in a tamper-proof manner. Serial numbers, QR codes, logos, or technical symbols can be engraved sharply into the surface without additives or tool wear.

Cleaning and decoating

Whether paint, rust, oxides, or production residues, laser cleaning removes unwanted layers precisely and without chemical additives. The base material remains undamaged, which is a clear advantage, especially in tool reconditioning and restoration.

Surface structuring

By specifically modifying surface roughness, subsequent processes such as bonding, coating, or printing can be optimized. In medical technology, implant surfaces are laser textured to enable improved cell adhesion and healing.

Micro-machining and semiconductor technology

In microelectronics, laser ablation is used for the structured removal of layers on wafers or in printed circuit boards. Its strengths are particularly evident in the case of sensitive components such as sensors or microchips, where contact-free and precise processing is required.

Medical applications

Laser ablation is also used in medical technology and surgery, for example in eye surgery, tumor removal, or minimally invasive tissue treatment. Here, it enables millimeter-precise procedures with minimal thermal impact.

Glass and polymer processing

Lasers are used to process glass in display technology, the pharmaceutical industry, and decorative engraving, for example. Plastics and polymers can be selectively removed, structured, or prepared for further processing, for example in medical device manufacturing or the packaging industry.

Overview of key process parameters

The quality of laser ablation depends largely on the selected process parameters. Precise adjustment enables optimal adaptation to the material, application, and desired result.

Wavelength and beam quality

The wavelength influences how well the material absorbs the laser. Metals respond better to fiber lasers, while plastics respond better to CO₂ lasers. The beam quality, measured by the M² value (quality parameter for laser beams), determines how precisely the beam can be focused.

Focus, pulse duration, and power

The focal distance determines where the laser delivers its highest energy. The pulse duration determines whether thermal effects occur. Ultra-short pulses minimize heat input. The average laser power and pulse frequency also influence the processing effect.

Movement and energy distribution

The scanning speed and pulse spacing determine how closely the laser points are distributed on the surface. Depending on the application, such as engraving or decoating, one or more passes are used.

Is laser ablation environmentally friendly?

Laser ablation is a non-contact, dry process, which is ideal for sustainable production.

No chemicals, no abrasion

Unlike traditional methods such as sandblasting or chemical cleaning, there is no hazardous waste or mechanical wear. Consumables such as abrasives or etching solutions are also not required.

Resource-efficient and effective

Since the energy is applied precisely and locally, overall energy consumption is significantly reduced. The high efficiency reduces costs and saves valuable resources. An extraction system ensures that any vapors produced are safely removed.

Conclusion

Laser ablation is a key technology in modern manufacturing. It offers high-precision material removal on a wide variety of materials: efficient, environmentally friendly, and flexible in use. From marking to cleaning, from engraving to texturing, laser ablation opens up completely new design possibilities in industrial production.