Selective thin-film ablation
Selective thin-film ablation
Removing thin layers from a carrier substrate
Defined removal of thin layers
Thanks to the concentration of the laser beam's energy in ultrashort pulses, the material to be processed can be vaporised directly. The heat input into the material remains minimal. This makes the ultrashort pulse laser ideal for removing a thin layer from a heat-sensitive base material. This process is used, for example, on electronic components to separate contacts by selectively removing material.
The advantages of layer ablation with the ultrashort pulse laser are:
High machining speed.
Only a few pulses are required to ablate layers, which means that a high machining speed can be realised thanks to high repetition rates.
Precise ablation with high precision in the µm range.
Minimal thermal stress. Thanks to minimal heat input during processing with the ultrashort pulse laser, the base material remains undamaged.
Force-free machining. No mechanical forces act on the component.
Precise ablation with high precision in the µm range.
Minimal thermal stress. Thanks to minimal heat input during processing with the ultrashort pulse laser, the base material remains undamaged.
Force-free machining. No mechanical forces act on the component.
Ablation of thin-layers
With the ultrashort pulse laser, layers can be removed from a base material in a defined manner. The special feature of ultrashort pulsed lasers is that no heat conduction takes place during the heat input and the material is vaporised directly without the formation of a significant melt layer. Material with a thickness of less than 1 µm is removed per pulse. In this way, layers can be precisely removed piece by piece
to create the desired structures. If the process is set up correctly, the base material is only minimally affected. Even at the edges of the ablation, no or only a minimal burr is formed due to the lack of a melt.
An essential factor that determines the processing quality is the separation of the layer to be removed from the base material. When removing layers with an ultrashort pulse laser, there are different mechanisms that can be used to achieve a clean separation of the layer from the base material. The best process results are obtained when the material to be ablated and the base material have very different optical properties. For example, if the base material is transparent to the laser wavelength and the layer to be ablated is not, the laser radiation is only absorbed by the layer to be ablated and an optimal processing result is obtained. But even with similar properties of both materials, the process can be adjusted in such a way that at least only a minimal influence on the base material takes place. Here, the correct setting of the energy density is particularly important. The energy density can be used to separate the removal of the layer and the base material if they have a different removal threshold. If the difference in the ablation threshold of both materials is large enough, the energy density of the laser beam can be adjusted so that only the layer is ablated and the base material is not damaged. If both materials have similar degrees of absorption and ablation thresholds, a layer ablation with minimal influence on the base material can be achieved by ablating material only to a defined depth, which is in the range of the layer thickness, through correct process settings. In this way, the layer can be reliably removed, although a certain impairment of the base material must be accepted.
The ultrashort pulse laser offers a variety of possibilities to remove a layer from a base material with high processing quality. We would be happy to discuss whether the ultrashort pulse laser is the right tool for your application in a free initial consultation! If you are interested in laser structuring, we look forward to hearing from you!
An essential factor that determines the processing quality is the separation of the layer to be removed from the base material. When removing layers with an ultrashort pulse laser, there are different mechanisms that can be used to achieve a clean separation of the layer from the base material. The best process results are obtained when the material to be ablated and the base material have very different optical properties. For example, if the base material is transparent to the laser wavelength and the layer to be ablated is not, the laser radiation is only absorbed by the layer to be ablated and an optimal processing result is obtained. But even with similar properties of both materials, the process can be adjusted in such a way that at least only a minimal influence on the base material takes place. Here, the correct setting of the energy density is particularly important. The energy density can be used to separate the removal of the layer and the base material if they have a different removal threshold. If the difference in the ablation threshold of both materials is large enough, the energy density of the laser beam can be adjusted so that only the layer is ablated and the base material is not damaged. If both materials have similar degrees of absorption and ablation thresholds, a layer ablation with minimal influence on the base material can be achieved by ablating material only to a defined depth, which is in the range of the layer thickness, through correct process settings. In this way, the layer can be reliably removed, although a certain impairment of the base material must be accepted.
The ultrashort pulse laser offers a variety of possibilities to remove a layer from a base material with high processing quality. We would be happy to discuss whether the ultrashort pulse laser is the right tool for your application in a free initial consultation! If you are interested in laser structuring, we look forward to hearing from you!
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LASER PRECISION 2023