METHODS FOR REMOVING DIRT DEPOSITS ON AT LEAST ONE GEOMETRIC STRUCTURE, PRODUCED BY MEANS OF MICROTECHNOLOGY AND/OR NANOTECHNOLOGY, OF AT LEAST ONE BODY AND USE OF AN ULTRA-SHORT PULSED LASER WITH PULSES IN BURST MODE

Abstract

The invention relates to methods for removing dirt deposits on at least one geometric structure of at least one body, said geometric structure being produced by means of microtechnology and/or nanotechnology, wherein the dirt deposits are dirt deposits resulting from an ablation or evaporation of material during creation of the geometric structure; and uses of an ultra-short pulsed laser with pulses in burst mode.

The methods for removing dirt deposits and the uses of an ultra-short pulsed laser with pulses in the burst mode are characterized more particularly in that the resulting dirt deposits are easy to remove. Ultra-short pulsed laser irradiation is applied from a laser onto the geometric structure with pulses in the burst mode to remove the dirt deposits.

Claims

1. A method for removing dirt deposits (debris) on at least one geometric structure of at least one body (8), said geometric structure being produced by means of microtechnology and/or nanotechnology, wherein the dirt deposits are dirt deposits resulting from an ablation or evaporation of material during creation of the geometric structure, characterized in that the geometric structure is exposed to ultra-short pulsed laser irradiation (4) from a laser (3) with pulses in burst mode to remove the dirt deposits.

2. The method according to claim 1, characterized in that the pulse repetition frequency in a burst is equal to/greater than 1 GHz and the pulse duration of a pulse in a burst is less than/equal to 1 ns.

3. The method according to claim 1, characterized in that a plasma is generated on the debris by a first pulse of the burst, and, by means of the interaction of at least one following pulse or following pulses of the burst with the plasma, a shock wave or shock waves is/are induced on the at least one dirt deposit, and the dirt deposit is removed.

4. The method according to claim 1, characterized in that the number of shock waves is determined by the number of following pulses in the burst.

5. The method according to claim 1, wherein the force of the shock wave is determined by the pulse duration and the fluence per following pulse.

6-9. (canceled)

10. The method according to claim 3, characterized in that the number of shock waves is determined by the number of following pulses in the burst.

11. The method according to claim 3, wherein the force of the shock wave is determined by the pulse duration and the fluence per following pulse.

Description

[0038] In the drawings:

[0039] FIG. 1 shows a schematic representation of pulsed laser irradiation with a single pulse mode,

[0040] FIG. 2 shows a schematic representation of pulsed laser irradiation with a burst mode; and

[0041] FIG. 3 shows a device for removing dirt deposits.

[0042] In the following exemplary embodiment, a method for removing dirt deposits (debris) on at least one geometric structure of at least one body 8, said geometric structure being produced by means of microtechnology and/or nanotechnology, wherein the dirt deposits are dirt deposits resulting from an ablation or evaporation of material during the creation of the geometric structure, and a use of an ultra-short pulsed laser 3 with pulses in the burst mode are explained together in more detail.

[0043] For this purpose, FIG. 1 shows a schematic representation of pulsed laser irradiation with a single pulse mode, and FIG. 2 shows a schematic representation of pulsed laser irradiation with a burst mode.

[0044] The burst mode is a laser technology in which pulse groups 2 having a defined number of pulses per pulse group 2 and a defined amount of pulse energy per pulse in a pulse group 2 interact with the material surface. A pulse group 2 is a burst. The pulse repetition frequency in a burst is greater than/equal to 1 GHz.

[0045] The pulse duration of a pulse in a pulse group 2 is equal to/less than 1 ns. FIG. 1 shows two individual pulses 1 with the pulse energy y as a function of time x. In FIG. 2, two pulse groups 2 and therefore two bursts with the pulse energy y as a function of time x are shown.

[0046] The first pulse of pulse group 2 of a pulse train (burst) generates a plasma on the debris. Due to the very short pulse repetition time of a few to several picoseconds, the following pulse interacts with this plasma. This induces a strong shock wave, and the debris is removed by a primarily mechanical process.

[0047] The number of shock waves can be regulated with the number of pulses in the burst. The force of the shock wave can be regulated with the pulse duration and the fluence per pulse.

[0048] FIG. 3 shows a device for removing dirt deposits in a basic illustration.

[0049] To remove dirt deposits, the laser 3 with the ultra-short pulsed laser irradiation 4 and at least one scanner 5 for guiding the laser irradiation 4 and/or at least one drive 6 as a movement mechanism connected to a carrier 7 of the body 8 can be used.

[0050] Using a scanner 5 and a downstream f-theta lens 9, the laser irradiation 4 can be guided over the surface of the geometric structure of the body 8. The f-theta lens 9 focuses the laser irradiation 4 on the focal point and, during scanning, causes the focal point to always lie in the working plane perpendicular to the optical axis of the f-theta lens 9. Furthermore, the position in the working plane approximately follows the f-theta condition; the scan length (image height) is approximately proportional to the set scan angle. The drive 6 can in particular be a device for movement in at least one direction of the carrier.