Method for micro-welding of flexible and thin films, for example for use in electrical and electronic devices

Abstract

The invention relates to a method for welding a flexible film (10) to a carrier part (20), having the following steps: 1) pressing the film (10) onto the carrier part (20) by means of the volumetric flow of a fluid, 2) laser welding the film (10) to the carrier part (20).

Description

TECHNICAL FIELD

[0001] The invention relates to a method for welding a flexible film to a carrier component. BACKGROUND

[0002] In thin, e.g. metallic films, the tensioning technique is of great importance for the joining process to a carrier component, which is also e.g. metallic, in order to ensure a technical zero gap. A technical zero gap is important because without a gap no heat transfer is possible and no weld seam can be produced and / or the film can be cut off unexpectedly. SUMMARY

[0003] The invention specifies a method for welding a flexible film to a carrier component. Further advantages, features and details of the invention result from the description and the drawings.

[0004] The invention specifies a method for welding (joining or materially connecting) a flexible film to a carrier component, with the following steps:

[0005] 1 ) pressing the film onto the carrier component by means of the volume flow of a fluid,

[0006] 2) laser welding the film onto the carrier component.

[0007] The method according to the invention can be used for welding flexible and thin films with layer thicknesses in the micrometer range. In other words, the method according to the invention can be referred to as a micro welding method. As a laser welding according to the invention, preferentially a heat conduction welding or a welding process close to the deep penetration welding threshold of the elements to be connected (film and carrier component) can be used.

[0008] The pressing according to the invention means pressing the film down onto the carrier component by means of a contactless tensioning technique in order to achieve a zero gap between the film and the carrier component, in particular in the region of the desired weld seam.

[0009] According to the invention, the volume flow of a fluid under pressure, preferably in the form of compressed air, nitrogen, protective gas (Ar, He, C02,...), etc. is used for the pressing.

[0010] The flexible film according to the invention can mean a thin film made of metal, e.g. copper, or plastic, with a layer thickness in the micrometer range, in particular between 20 μm and 100 μm, preferably 35 μm. The flexible film according to the invention can for example mean a flexible printed conductor in a flexible circuit board, i.e. a so-called flexible printed circuit board or FPC for short.

[0011] The carrier part according to the application can refer to a carrier part made of metal, for example copper, or plastic, with a layer thickness in the micrometer range, in particular between 50 μm and 500 μm, preferably between 50 μm and 140 μm, preferably 135 μm. The carrier part according to the application can for example refer to an electrical carrier part, for example in the form of a landing on for example a rigid circuit board, i.e. a so-called printed circuit board or short PCB.

[0012] The application provides a new welding method for connecting thin, for example metallic, films to a carrier material, for example also thin. The inventive idea here is to use a volume flow of a fluid, preferably under pressure, in order to realize a contactless tensioning technique for pressing the film down onto the carrier part. Thereby a low-loss heat transfer between the film and the carrier part can be realized immediately prior to the welding in order to create a weld seam. Furthermore, the volume flow also realizes a nearly technical zero gap. Thereby it is also ensured that the film is not accidentally cut off due to a gap and / or too high laser radiation. Furthermore, the suggested contactless tensioning technique eliminates or at least reduces metal vapors which disturb the welding process.

[0013] The method according to the application can in principle be used for contacting thin metallic printed conductors to any type of electronic device. The method according to the application can for example be used for contacting conductor bridges in microprinted structural elements, for example when building MEMS devices, for example by combining a laser-induced forward transfer method (LIFT) with the micro welding method according to the application. The method according to the application can also be used in battery management systems (for example in lithium-ion batteries), in particular for contacting thin metallic flat conductors to a circuit board (for example for voltage tapping when monitoring the battery voltage, for example). The method according to the application can also be used for contacting thin current carrier films or current carrier plates to the terminals of a battery cell (for example a round battery cell in a lithium-ion battery).

[0014] It is also conceivable that the method according to the application is extended to connecting non-metallic films (for example made of plastic) to metallic or non-metallic carrier materials (for example for the packaging industry, medical technology, sensors, etc.) by means of laser radiation using a small laser beam quality (for example by means of a diode laser).

[0015] Furthermore, the application can provide in the method for welding a flexible film to a carrier part that in step 1 ) a fluid is used, for example in the form of a fluid under pressure, preferably in the form of compressed air, nitrogen, a protective gas (Ar, He, CO2,...), etc. In this way it is not only possible to press the film down onto the carrier part, but also to prepare for the subsequent laser welding. It is also conceivable that a protective gas makes the laser welding possible or at least easier.

[0016] Furthermore, the present application can provide in the method for soldering a flexible film to a carrier component that in step 1 ) a volume flow is generated by means of a nozzle or a nozzle comb. With the aid of a nozzle the volume flow can be accelerated and thus a suitable pressure can be set to press the film down onto the carrier component. With the aid of a nozzle comb a plurality of films can be pressed simultaneously onto the respective carrier component, for example onto a circuit board.

[0017] Furthermore, the present application can provide in the method for soldering a flexible film to a carrier component that in step 2) laser radiation in the visible wavelength range, preferably in the green wavelength range (about 490 nm - 560 nm) and / or in the blue wavelength range (about 380 nm - 480 nm) or near-infrared laser radiation is used. Laser radiation in the green wavelength range and partly in the blue wavelength range has proven to be advantageous in order to make possible a thermocompression soldering of the elements to be connected (film and carrier component) made of copper, even un-tinned. Near-infrared laser radiation can make possible a soldering process close to the deep-penetration welding threshold of the elements to be connected. Thus a joining or connecting of the elements at the weld contour can be made possible.

[0018] Furthermore, the present application can provide in the method for soldering a flexible film to a carrier component that in step 2) pulsed laser radiation, quasi-continuous laser radiation or continuous laser radiation is used. Pulsed laser radiation can provide a peak power within a pulse. Pulsed laser radiation can be advantageous when using near-infrared laser radiation in order to achieve sufficient adhesion between the elements along the contour of a plurality of, for example point-by-point, welds. Quasi-continuous laser radiation can achieve the application of a peak power in addition to a narrow spectrum. Quasi-continuous laser radiation can be advantageous when using green and blue laser radiation. Continuous laser radiation can achieve a precise setting of the weld penetration depth.

[0019] Furthermore, the present application can provide in the method for soldering a flexible film to a carrier component that in step 2) a 2D galvanometer scanner, a ID / 2D polygon scanner or a diode laser is used to generate the laser radiation. A 2D galvanometer scanner and a ID / 2D polygon scanner can be advantageous in order to manufacture and furthermore to inspect or scan the weld. A diode laser can be advantageous in order to provide laser radiation with a small laser beam quality, which can be advantageous for soldering non-metallic films, for example made of plastic, to metallic or non-metallic carrier components, for example in the packaging industry, in medical technology or in sensor technology.

[0020] Furthermore, the application can provide in the method for welding a flexible film to a carrier component that in step 2) a weld seam of a settable depth is produced. By means of the settable depth, the method according to the application can be flexibly adapted to films of different thicknesses. In some cases, an additional coating or tinning of the elements to be connected can even be dispensed with by means of the settable depth. In particular, it is thus possible to set the heat conduction in such a way that the material of the carrier component is heated sufficiently in the region of the desired weld seam in order to establish a material-bonding connection to the film, but without damaging or even tearing the film.

[0021] Furthermore, the application can provide in the method for welding a flexible film to a carrier component that in step 2) a heat conduction welding or a process close to the deep-penetration welding threshold is used for the carrier component. The method according to the application can in this way make it possible to weld thin metal elements as reliably as possible and at the same time can process the thin elements to be connected protectively. In addition, no spattering occurs in the heat conduction welding, which is advantageous in electronic components.

[0022] Furthermore, the application can provide in the method for welding a flexible film to a carrier component that in step 2) laser radiation, in particular quasi-continuous laser radiation, having at least one of the following parameters is used:

[0023] - a wavelength of 500 nm - 600 nm, in particular 515 nm,

[0024] - a focal diameter of 20 μm - 1 mm, in particular 150 μm,

[0025] - a power of 1 W - 4000 W, in particular 200 W - 600 W,

[0026] - a pulse duration of 0.3 ms - 50 ms, in particular 2 ms - 6 ms,

[0027] - a scanning speed of 1 mm / s - 1 km / s, in particular 200 mm / s - 300 mm / s.

[0028] The conductor tracks are mostly made of copper. In the case of the use of such preferably green laser radiation, the absorption in copper elements (film and carrier component) is increased by at least 35% compared to the treatment of copper with conventional laser beam sources, for example in the near-infrared range. The heat conduction welding of copper elements is thus achieved by the use of such laser radiation, for example by means of green quasi-continuous laser radiation, even without a tinning of the copper. In this way, the micro-welding according to the application of thin copper elements is achieved.

[0029] It is also conceivable that in step 2) a circular weld seam or a linear weld seam having a diameter of 0.1 mm - 10 mm, in particular 0.1 mm - 0.4 mm, is produced. It is also conceivable that in step 2) a weld seam having a length of 0.1 mm - 5 mm, in particular 0.5 mm, is produced. By means of such a weld seam the film can be connected to the carrier part protectively but also reliably.

[0030] Furthermore, the application can provide in the method for welding a flexible film to a carrier part that in step 2) laser radiation, in particular pulsed laser radiation, having at least one of the following parameters is used:

[0031] - wavelength: 1030 nm - 1064 nm,

[0032] - focal diameter: 10 μm - 500 μm, in particular 20 μm - 200 μm,

[0033] - power: 1 W - 2000 W, in particular 10 W - 500 W, preferably 20 W - 100 W,

[0034] - frequency: 1 Hz - 2000 kHz, in particular 1000 Hz - 2000 Hz,

[0035] - pulse duration: 1 ns - 500 ns, in particular 120 ns - 500 ns,

[0036] - scanning speed: 1 mm / s - 1 km / s, in particular 10 mm / s - 1000 mm / s, in particular 10 mm / s - 100 mm / s,

[0037] and / or in step 2) a linear weld seam or a plurality of linear weld seams, in particular parallel linear weld seams, is produced,

[0038] and / or in step 2) a weld seam having a length of 0.1 mm - 5 mm, in particular 0.4 mm, is produced.

[0039] In the case of the use of such preferably near-infrared or pulsed laser radiation it is possible to weld copper elements at the edges of the weld seam.

[0040] Furthermore, the application can provide in the method for welding a flexible film to a carrier component that the film, in particular in the form of flexible printed conductors embedded in a flexible printed circuit board, is pre-deformed before step 1). This makes it easier to press the film down onto the carrier component to establish a zero gap between the film and the carrier component. This also improves the accuracy and target precision when making the weld.

[0041] Furthermore, the application can provide in the method for welding a flexible film to a carrier component that the weld (N) is checked, in particular optically, for conductivity, resistance and / or impedance after step 2), wherein, in particular depending on the check, a re-welding can be carried out. In this way, the reject rate of the finished product can be significantly reduced.

[0042] Furthermore, the application can provide that the method is used to weld a plurality of flexible films to a plurality of carrier components in the same cycle. Thus, a plurality of functional components can be connected simultaneously to corresponding carrier components, for example circuit boards.

[0043] It is also conceivable to use the method to weld a metal, in particular copper, or plastic flexible film to a metal, in particular copper, or plastic carrier component. In this way, the range of application of the method according to the application can advantageously be broadened.

[0044] It is also conceivable within the scope of the application that the method can be used to weld thin metal printed conductors to electrical carrier components, for example in the form of pads in sensors in microprinted structural elements in electronic devices, in electrochemical transducers, in particular in batteries or fuel cells, on circuit boards.

[0045] The method can advantageously be used to weld a flexible film in the form of flexible printed conductors embedded in a flexible printed circuit board to an electrical carrier component in the form of pads on a rigid printed circuit board. The method can in particular be used to weld a flexible film (10) having a layer thickness of 20 μm - 100 μm, in particular 35 μm, to an electrical carrier component (20) having a thickness of 50 μm - 500 μm, for example 50 μm - 140 μm, in particular 135 μm.

[0046] The application also provides for the use of an energy system in a mobile environment, for example in a vehicle, or in a static environment, for example in a power generator installation. BRIEF DESCRIPTION OF DRAWINGS

[0047] The application and its advantageous embodiments and extensions are explained in more detail below with the aid of the drawings. The following is shown schematically:

[0048] Figure 1 is an exemplary view of an element to be connected according to the application;

[0049] Figure 2 is an exemplary view of a first method step according to the application;

[0050] Figure 3 is an exemplary view of a second method step according to the application;

[0051] Figure 4 is an exemplary view of an optional prepared method step according to the application;

[0052] Figure 5 is an exemplary view of a flexible film according to the application;

[0053] Figure 6 is an exemplary view of a carrier component according to the application;

[0054] Figure 7 is an absorption diagram for laser radiation of copper;

[0055] Figure 8 is an example of a weld seam according to the application; and

[0056] Figure 9 is another example of a weld seam according to the application.

[0057] In the different figures the same parts of the application are always provided with the same reference numerals, so that these parts are generally only explained once. DETAILED DESCRIPTION

[0058] Figures 1 to 4 It is intended to illustrate a method according to the application for welding a flexible film 10 to a carrier component 20. Figures 1 to 4 A schematic structure for carrying out the method according to the application is shown.

[0059] Figures 1 to 4 A possible film 10 according to the application is shown, which can be designed in the form of flexible printed conductors which are embedded in a flexible printed circuit board (flexible printed circuit board or FPC for short).

[0060] Figure 5 A flexible printed circuit board FPC with a plurality of embedded flexible printed conductors is subsequently shown as a possible flexible film 10 according to the application. Here, each flexible printed conductor can consist of copper Cu and have a thickness or layer thickness of 20 μm to 100 μm, in particular 35 μm. The surface of the flexible printed conductor which is left free can be designed to be chemically tinned or untinned. According to the application, the flexible printed circuit board FPC has the following structure: Figure 5 ​

[0061] Base film 25 μm, polyamide;

[0062] Adhesive 28 μm;

[0063] Signal layer 35 / 70 μm Cu, chemical tin;

[0064] Adhesive 60 μm;

[0065] Cover film 25 μm, polyamide.

[0066] Furthermore, Figures 1 to 4 Possible carrier parts 20 in the form of electrical carrier parts 20, in particular in the form of pads on a rigid printed circuit board (PCB) are also shown.

[0067] Figure 6 A plurality of electrical carrier parts 20 in the form of a plurality of pads on a rigid printed circuit board PCB is subsequently shown. The carrier parts 20 (so-called pads) can have a thickness of 50 μm to 500 μm, for example 50 μm to 140 μm, in particular 135 μm. Therein, about 30 μm to 120 μm

[0068] The approximately 20 μm assigned to the Cu base layer itself and to the galvanically applied Cu layer, respectively (cf. the separation line T of the dashed line in the cross-sectional view below Figure 6 the pad surface can be chemically tin-plated, but can also be designed to be not tin-plated.

[0069] It is also conceivable, however, that the method according to the application can be used to contact thin metallic printed conductors with electronic devices of any type, such as micro-printed structural elements, sensor devices, electrochemical transducers, in particular batteries or fuel cells.

[0070] Figure 2 A first step of the method according to the application is shown:

[0071] 1) pressing the film 10 onto the carrier part 20 by means of the volumetric flow of the fluid;

[0072] Here, a fluid under pressure, preferably in the form of compressed air, nitrogen or a protective gas (Ar, He, CO2,...) or the like is used as the fluid.

[0073] Figure 3 A second step of the method according to the application is shown:

[0074] 2) laser welding the film 10 onto the carrier part 20.

[0075] As laser welding according to the application, it is possible to use, for example, heat-conducting welding or welding processes which approach the deep-penetration welding threshold of the elements 10, 20 (film 10 and carrier part 20) to be connected.

[0076] Figure 4 It is also shown that, prior to step 1), the film 10 can be pre-deformed, in particular pot-shaped, by means of a micro-deformation and / or deep-drawing by means of a stamping die S and a counter-die M in order to over-extend the film 10 purposefully.

[0077] Figure 7 The absorption of laser radiation of different wavelengths in copper Cu is shown by means of diagrams, in particular for green laser radiation and for near-infrared laser radiation. It is shown that Figure 7 It is shown that, in the case of the use of green laser radiation, the absorption in copper Cu is increased by 35% compared to the processing of copper Cu with conventional laser radiation sources in the near-infrared range NIR. By using green laser radiation, micro-welding of Cu compounds is thus also achieved.

[0078] The green laser radiation used in step 2) of the method according to the application, in particular in the form of quasi-continuous laser radiation, can have at least one of the following parameters and / or properties:

[0079] - wavelength: 500 nm - 600 nm, in particular 515 nm,

[0080] - focal point diameter: 20 pm - 1 mm, in particular 150 pm,

[0081] - focal point position: z = 0 mm to z = + / - 2 zR, in particular z = + / - 1 zR,

[0082] - power: 1 W - 4000 W, in particular 200 W - 600 W,

[0083] - pulse duration: 0.3 ms - 50 ms, in particular 2 ms - 6 ms,

[0084] - pulse shape: rectangular, ramp,

[0085] - scan speed: 1 mm / s - 1 km / s, in particular 200 mm / s - 300 mm / s,

[0086] - scan technology: 2D galvanometer scanner, 1D / 2D polygon scanner,

[0087] - weld seam length: 0.1 mm - 5 mm, in particular 0.5 mm

[0088] - geometry of the weld: with a circle having a diameter of 0.1 mm - 10 mm, in particular 0.1 mm - 0.4 mm, or with a line having a length of 0.1 mm - 5 mm, in particular 0.5 mm.

[0089] Figure 8 A circular weld is shown, which can be produced by means of laser radiation, in particular green laser radiation in the form of quasi-continuous laser radiation. According to Figure 8 The welding process of a flexible printed circuit board FPC on a rigid printed circuit board PCB can be carried out in one laser pulse. This laser pulse can have a duration of about 2 ms - 5 ms within the scope of the present application. In this time, a laser beam in the shape of a circle or in the shape of a line is guided over the surface of the flexible printed circuit board FPC on the rigid printed circuit board PCB (so-called long-pulse welding or quasi-continuous welding). A ring-shaped or line-shaped micro-weld having a weld length s is thus produced during the pulse. The weld depth can advantageously be controlled by the so-called distance energy L (quotient of laser power & movement speed).

[0090] .

[0091] In certain process regimes (depending on the Cu / Sn layer thickness of the flexible printed circuit board FPC and the rigid printed circuit board PCB), the weld-in depth rises with increasing laser power at constant processing speed and laser focus area, without damaging the components 10, 20 to be connected.

[0092] Figure 9 A plurality of line-shaped welds is shown, which can be produced by means of near-infrared laser radiation, in particular near-infrared laser radiation in the form of pulsed laser radiation. In the case of the use of pulsed near-infrared laser radiation, energy / heat can still be stored in the material despite the low absorption, since the pulsed near-infrared laser radiation has a small focus diameter and the resulting high intensity triggers a deep-penetration welding effect. Micro-welding of Cu compounds according to the present application is thus also made possible by the use of pulsed near-infrared laser radiation.

[0093] The near-infrared laser radiation, in particular near-infrared laser radiation in the form of pulsed laser radiation, used in step 2) of the method according to the present application can have at least one of the following parameters and / or properties:

[0094] - laser focus diameter: 10 μm - 500 μm, in particular 20 μm - 200 μm,

[0095] - wavelength: 1030 nm - 1064 nm;

[0096] - Power: 1 W - 2000 W, in particular 10 W - 500 W, in particular 20 W - 100 W;

[0097] - Response rate: 1 Hz - 2000 kHz, in particular 1000 Hz - 2000 Hz;

[0098] - Pulse duration: 1 ns - 500 ns, in particular 120 ns - 500 ns;

[0099] - Geometry: line (0.4 mm long, 100 μm hatching, other geometries are also conceivable);

[0100] - Scan speed: 1 mm / s - 1 km / s, in particular 10 mm / s - 1000 mm / s, in particular 10 mm / s - 100 mm / s;

[0101] - Scan technology: 2D galvanometer scanner, 1D / 2D polygon scanner.

[0102] According to Figure 9 , the soldering process between flexible printed circuit boards FPC on rigid printed circuit boards PCB can be performed with the aid of a plurality of laser pulses. The individual laser pulses can have a typical duration of approximately 120 ns (longer pulses of up to 500 ns are also conceivable if necessary) in this case. During the soldering time, a laser beam in the form of a line is guided over the surface of the flexible printed circuit board FPC on the rigid printed circuit board PCB. A plurality of linear micro-welds with a weld length s composed of a plurality of pulses are thus produced. The heat input into the material required for the soldering process can be controlled by the so-called heat accumulation of the individual laser pulses, whereby an average heating ΔT is obtained.

[0103]

[0104] .

[0105] In the center of the laser beam, the material evaporates, forming a weld along the ablated outer surface. Here, the tin Sn can melt and the copper Cu can also melt in a thin edge zone.

[0106] It is furthermore conceivable that the method according to the application can be extended to the joining of non-metallic films (for example made of plastic) on metallic or non-metallic carrier materials (for example for the packaging industry, medical technology, sensors, etc.) with the aid of the use of laser radiation with small laser beam quality (for example with the aid of diode lasers).

[0107] The foregoing description of the drawings merely explains the illustrated embodiments. The various features of the embodiments can, of course, be combined in any combination of one or more features, as would be technically reasonable, without departing from the scope of the present invention.

Claims

1. Method for welding a flexible film (10) to a carrier part (20), characterized in that, The flexible film (10) is embedded in a flexible printed circuit board FPC in the form of a flexible printed conductor, the carrier component (20) is arranged on a rigid printed circuit board PCB in the form of a solder pad, the method has the following steps: 1) pressing the film (10) onto the carrier component (20) by means of a volumetric flow of a fluid, 2) laser welding the film (10) to the carrier component (20), wherein, prior to step 1), a pre-deformation of the film (10) is carried out without using the volumetric flow of the fluid and without carrying out a pre-deformation of the carrier component (20).

2. The method according to claim 1, characterized in that in step 1), the fluid is used in the form of a fluid under pressure, and / or in step 1), the volumetric flow is generated by means of a nozzle or a nozzle comb.

3. The method according to claim 2, characterized in that in step 1), the fluid is used in the form of compressed air, nitrogen and / or a protective gas.

4. The method according to any one of claims 1 to 3, characterized in that in step 2), laser radiation in the visible wavelength range or near-infrared laser radiation is used, and / or in step 2), pulsed laser radiation, quasi-continuous laser radiation or continuous laser radiation is used.

5. The method according to claim 4, characterized in that in step 2), laser radiation in the green wavelength range and / or in the blue wavelength range is used.

6. The method according to any one of claims 1 to 3, characterized in that in step 2), laser radiation having at least one of the following parameters is used: - wavelength: 500 nm - 600 nm, - focal point diameter: 20 μm - 1 mm, - power: 1 W - 4000 W, - pulse duration: 0.3 ms - 50 ms, - scan speed: 1 mm / s - 1 km / s.

7. The method according to claim 6, characterized in that the laser radiation has a wavelength of 515 nm.

8. The method according to claim 6, characterized in that the laser radiation has a focal point diameter of 150 μm.

9. The method according to claim 6, characterized in that the laser radiation has a power of 200 W - 600 W.

10. The method according to claim 6, characterized in that the laser radiation has a pulse duration of 2 ms - 6 ms.

11. The method according to claim 6, characterized in that the laser radiation has a scan speed of 200 mm / s - 300 mm / s.

12. The method according to claim 6, characterized in that the laser radiation is quasi-continuous laser radiation.

13. The method according to any one of claims 1 to 3, characterized in that in step 2), laser radiation having at least one of the following parameters is used: - wavelength: 1030 nm - 1064 nm, - focal point diameter: 10 μm - 500 μm, - power: 1 W - 2000 W, - frequency: 1 Hz - 2000 kHz, - pulse duration: 1 ns - 500 ns, - scan speed: 1 mm / s - 1 km / s.

14. The method according to claim 13, characterized in that the laser radiation has a focal point diameter of 20 μm - 200 μm.

15. The method according to claim 13, characterized in that the laser radiation has a power of 10 W - 500 W.

16. The method according to claim 13, characterized in that the laser radiation has a power of 20 W - 100 W.

17. The method according to claim 13, characterized in that the laser radiation has a frequency of 1000 Hz - 2000 Hz.

18. The method according to claim 13, characterized in that the laser radiation has a pulse duration of 120 ns - 500 ns.

19. The method according to claim 13, characterized in that the laser radiation has a scan speed of 10 mm / s - 1000 mm / s.

20. The method according to claim 13, characterized in that the laser radiation has a scan speed of 10 mm / s - 100 mm / s.

21. The method according to claim 13, characterized in that the laser radiation is pulsed laser radiation.

22. The method according to any one of claims 1 to 3, characterized in that the conductivity, the resistance and / or the impedance of the weld seam (N) is checked after step 2).

23. The method according to any one of claims 1 to 3, characterized in that the method is used in the same cycle to weld a plurality of flexible films (10) to a plurality of carrier parts (20), and / or the method is used to weld a metal or plastic flexible film (10) to a metal or plastic carrier part (20).

24. The method according to claim 23, characterized in that the flexible film (10) is made of copper.

25. The method according to claim 23, characterized in that the carrier part (20) is made of copper.

26. The method according to any one of claims 1 to 3, characterized by, The method is used to weld thin metal printed conductors to electrical carrier parts in electronic devices, in micro-printed structural elements, in sensor devices, in electrochemical transducers.

27. The method of claim 26, wherein, The method is used to weld thin metal printed conductors to electrical carrier parts in batteries or fuel cells.

28. The method according to any one of claims 1 to 3, characterized by, The method is used to weld a flexible film (10) in the form of a flexible printed conductor embedded in a flexible printed circuit board (FPC) to an electrical carrier part (20) in the form of a pad on a rigid printed circuit board (PCB), and / or the method is used to weld a flexible film (10) having a layer thickness of 20 μm - 100 μm to an electrical carrier part (20) having a thickness of 50 μm - 500 μm.

29. The method according to claim 28, characterized in that The flexible film (10) has a layer thickness of 35 μm.

30. The method according to claim 28, characterized in that The electrical carrier component (20) has a thickness of 50 μm - 140 μm.

31. The method according to claim 28, characterized in that The electrical carrier component (20) has a thickness of 135 μm.

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