Method for microwelding flexible thin films, for example for use in electrical and electronic devices

Patent metadata

Field	Value
Publication number	US-12318864-B2
Application number	US-202017036031-A
Country	US
Kind code	B2
Filing date	Sep 29, 2020
Priority date	Sep 30, 2019
Publication date	Jun 3, 2025
Grant date	Jun 3, 2025

Abstract

A method for welding a flexible film ( 10 ) to a carrier component ( 20 ) having the following steps:
1) pressing the film ( 10 ) on the carrier component ( 20 ) by a volumetric flow of a fluid, and 2) laser welding the film ( 10 ) on the carrier component ( 20 ).

First claim

What is claimed is:

1. A method for welding a flexible film ( 10 ) to a carrier component ( 20 ), having the following steps:
1) Pressing the film ( 10 ) on the carrier component ( 20 ) by a volumetric flow of a fluid, and
2) laser welding the film ( 10 ) on the carrier component ( 20 ),
wherein before step 1), a pre-deforming of the film ( 10 ) is performed using a method that does not include the volumetric flow of fluid and is done by means of a negative mold (M), and
wherein the method is used for welding a flexible film ( 10 ) in the form of a flexible trace embedded within a flexible circuit board (FPC) to an electrical carrier component ( 20 ) in the form of landing on a rigid circuit board (PCB).

2. The method according to claim 1 , wherein, in step 1), the fluid is a pressurized fluid, and/or wherein, in step 1), the volumetric flow is produced by a nozzle or a nozzle comb.

3. The method according to claim 2 , wherein the pressurized fluid is in the form of compressed air, nitrogen and/or shielding gas.

4. The method according to claim 1 , wherein, in step 2), a laser radiation in the visible wavelength range, or an NIR laser radiation is used, and/or wherein, in step 2), a pulsed laser radiation, a quasi CW laser radiation or a CW laser radiation is used.

5. The method according to claim 4 , wherein the laser in the visible wavelength range is in the green wavelength range and/or in the blue wavelength range.

6. The method according to claim 1 , wherein, in step 2), a laser radiation with at least one of the following parameters is used:
a wavelength of 500 nm-600 nm,
a focus diameter of 20 μm-1 mm,
a power output of 1 W-4000 W,
a pulse duration of 0.3 ms-50 ms,
a scanning rate of 1 mm/s-1 km/s.

7. The method according to claim 6 , wherein the laser radiation is a quasi CW laser radiation, with at least one of the following parameters:
a wavelength of 515 nm,
a focus diameter of 150 μm,
a power output of 1 200 W-600 W,
a pulse duration of 2 ms-6 ms,
a scanning rate of 200 mm/s-300 mm/s.

8. The method according to claim 1 , wherein, in step 2), a laser radiation with at least one of the following parameters is used:
a wavelength of 1030 nm-1064 nm,
a focus diameter of 10 μm-500 μm,
a power output of 1 W-2000 W,
a frequency of 1 Hz-2000 kHz,
a pulse duration of: 1 ns-500 ns,
a scanning rate of: 1 mm/s-1 km/s.

9. The method according to claim 8 , wherein the laser radiation is a pulsed laser radiation, with at least one of the following parameters:
a wavelength of 1030 nm-1064 nm,
a focus diameter of 20 μm-200 μm,
a power output of 10 W-500 W,
a frequency of 1000 Hz-2000 Hz,
a pulse duration of: 120 ns-500 ns,
a scanning rate of: 10 mm/s-1000 mm/s.

10. The method according to claim 9 , wherein the laser radiation is a pulsed laser radiation, with at least one of the following parameters:
a power output of 20 W-100 W
a scanning rate of: 10 mm/s-100 mm/s.

11. The method according to claim 8 , wherein the laser radiation is a pulsed laser radiation.

12. The method according to claim 1 , wherein, after step 2), a testing of a weld seam (N) for conductivity, resistance and/or impedance is performed.

13. The method according to claim 1 , wherein the method is used for welding multiple flexible films ( 10 ) to multiple carrier components ( 20 ) in the same pass.

14. The method according to claim 1 , wherein the method is used for welding a flexible film ( 10 ) of a layer thickness of 20 μm-100 μm, to an electrical carrier component ( 20 ) of a thickness of 50 μm-500 μm.

15. The method according to claim 14 , wherein the method is used for welding a flexible film ( 10 ) of a layer thickness of 35 μm, to an electrical carrier component ( 20 ) of a thickness of 50 μm-140 μm.

16. The method according to claim 15 , wherein the method is used for welding a flexible film ( 10 ) of a layer thickness of 35 μm, to an electrical carrier component ( 20 ) of a thickness of 135 μm.

17. The method according to claim 1 , wherein the metal is copper.

18. The method according to claim 1 , wherein the pre-deforming of the film ( 10 ) includes using a punch(S).

19. The method according to claim 18 , wherein the punch(S) is an embossing punch(S) that cooperates with the negative mold (M).

20. The method according to claim 1 , wherein the pre-deforming of the film ( 10 ) includes deep drawing the film ( 10 ).

21. The method according to claim 1 , wherein the pre-deforming of the film ( 10 ) includes microdeforming the film ( 10 ).

Assignees

• Bosch Gmbh Robert

Inventors

• Heider Andreas
• Bormann Axel
• Kunz Gerhard
• Proell Johannes
• Alter Lukas

Classifications

• B23K26/123

  in an atmosphere of particular gases · CPC title

• B23K2101/42

  Printed circuits · CPC title

• B23K2103/12

  Copper or alloys thereof · CPC title

• B23K26/60

  Preliminary treatment · CPC title

• B23K26/082

  Scanning systems, i.e. devices involving movement of the laser beam relative to the laser head · CPC title