Laser nanomachining device and method

Patent metadata

Field	Value
Publication number	US-10131017-B2
Application number	US-201314394159-A
Country	US
Kind code	B2
Filing date	Apr 12, 2013
Priority date	Apr 13, 2012
Publication date	Nov 20, 2018
Grant date	Nov 20, 2018

Abstract

According to one aspect, the invention relates to a device ( 1, 2, 3 ) for laser nanomachining a sample made of a material having a given transparency band, the device comprising: a focusing module ( 203, 703 ) allowing a nondiffracting beam ( 210, 710 ) to be generated, along a focusing line generally oriented along the optical axis of the focusing module, from a given incident beam; first means ( 202, 702 ) for emitting a first light pulse (I 1 ) of spectral band comprised in the transparency band of said material, able to generate in said material, after focusing by said focusing module, a plasma of free charges along said focusing line via multi-photon absorption, thus forming a “plasma channel”; and second means ( 202, 702 ) for emitting at least one second electromagnetic wave (I 2 ) of spectral band comprised in the transparency band of said material, which wave(s) is/are intended to be spatially superposed on said plasma channel in order to heat said material via absorption by the free charges of the plasma.

First claim

The invention claimed is:

1. A device for laser nanomachining a sample made of a material having a given transparency band, the device comprising:
a focusing module allowing, from a given incident beam, a non-diffracting beam to be generated along a focal line generally oriented along the optical axis of the focusing module;
first emitter that emits a first light pulse in a spectral band comprised in the transparency band of said material, able to generate in said material, after focusing by said focusing module, a plasma of free carriers along said focal line via multi-photon absorption, thus forming a plasma channel; and
second emitter that emits at least one second electromagnetic wave in a spectral band comprised in the transparency band of said material, intended to be collinear with said plasma channel in order to heat said material via absorption by the free carriers of the plasma.

2. The device as claimed in claim 1 , wherein said first light pulse has a duration shorter than 10 picoseconds.

3. The device as claimed in claim 1 , wherein said second emitter allows a train of light pulses to be emitted.

4. The device as claimed in claim 1 , wherein said first and second emitters are formed by two separate synchronized laser sources.

5. The device as claimed in claim 1 , wherein said first and second emitters are formed by a source emitting a single laser pulse and a temporal shaping module, allowing a first and at least one second light pulses to be generated from the light wave emitted by said laser source.

6. The device as claimed in claim 5 , wherein said temporal shaping module comprises a beam splitter allowing at least two channels to be formed, and, in at least one of the channels, a pulse stretcher.

7. The device as claimed in claim 5 , wherein said temporal shaping module comprises an acousto-optic programmable dispersive system.

8. The device as claimed in claim 5 , further comprising a frequency converting module downstream of said temporal shaping module.

9. The device as claimed in claim 1 , wherein the focusing module allows a Bessel beam to be generated.

10. The device as claimed in claim 1 , wherein the focusing module allows an Airy beam to be generated.

11. The device as claimed in claim 1 , wherein said focusing module allows a matrix of non-diffracting beams to be formed.

12. A method for laser nanomachining a sample made of a material having a given transparency band, the method comprising:
emitting a first pulse in a spectral band comprised in the transparency band of said material;
spatial shaping of said first pulse, allowing, after focusing in said sample, a non-diffracting beam to be formed along a focal line, the light intensity of said non-diffracting beam allowing a plasma of free carriers to be generated along said focal line via multi-photon absorption, thus forming a plasma channel; and
emitting at least one second electromagnetic wave in a spectral band comprised in the transparency band of said material, collinear with said plasma channel in order to heat said material via absorption by the free carriers of the plasma.

13. The method as claimed in claim 12 , wherein the spatial shaping of said first pulse furthermore comprises spatial modulation of the amplitude of said pulse in order to make the light intensity of said first pulse substantially constant over said focal line.

14. The method as claimed in claim 12 , applied to nano-drilling of a sample made of a given material in order to form a channel, comprising:
controlling the position and the length of the channel to be drilled via the spatial shaping and light intensity of said first light pulse; and
controlling the diameter of the channel via the energy deposited by said second electromagnetic wave(s) in the plasma channel thus formed.

15. The method as claimed in claim 12 , wherein the sample is made of a semiconductor.

Assignees

• Courvoisier Francois
• Lacourt Pierre Ambroise
• Jacquot Maxime
• Furfaro Luca
• Dudley John
• De Labachelerie Michel
• Centre National De La Rech Scientifique—Cnrs
• Univ Franche Comte

Inventors

• Courvoisier François
• Lacourt Pierre-Ambroise
• Jacquot Maxime
• Furfaro Luca
• Dudley John
• De Labachelerie Michel

Classifications

• H10P95/906

  for altering the shape of semiconductors, e.g. smoothing the surface · CPC title

• H10P72/0436

  mainly by radiation · CPC title

• B23K2203/50

  Operations & Transport · mapped topic

• B23K26/382

  by boring · CPC title

• H05K3/0038

  combined with laser drilling through a metal layer · CPC title