Cutting method of flexible circuit board

Abstract

The cutting method of the flexible circuit board comprises the steps that a first laser beam is adopted to irradiate and cut a first flexible layer to expose a metal wire layer, and the first laser beam has first output power and first output pulse frequency; using a second laser beam to irradiate and cut the metal wire layer to expose the second flexible layer, wherein the second laser beam has a second output power greater than the first output power and a second output pulse frequency greater than the first output pulse frequency; and the second flexible layer is cut through first laser beam irradiation. The method is simple and easy to control, different output powers and pulse frequencies of the laser beams are adjusted and controlled according to different cut layer bodies, so that the cutting effect is better controlled, excessive melting of the flexible layer and excessive warping of the metal wire layer are avoided, and then the quality performance of the flexible circuit board is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of flexible circuit board processing, and more particularly to a method for cutting flexible circuit boards. Background Technology

[0002] With the development of the electronics industry, flexible circuit boards are widely used in various fields. Cutting flexible circuit boards is an essential step in the processing, and the cutting effect plays a crucial role in the performance of the flexible circuit boards.

[0003] The common traditional cutting methods for flexible circuit boards are mechanical cutting and laser cutting, which cut the flexible circuit board in one go. In other words, the multiple layers of the flexible circuit board are cut and separated in a single cutting operation. Although this operation can ensure cutting efficiency, it has different effects on different layers of the flexible circuit board. For example, the flexible PET layer is prone to over-melting, and the metal conductor layer is prone to warping of the cut edge due to excessive stress.

[0004] Therefore, there is an urgent need to provide an improved cutting method for flexible circuit boards to overcome the above defects. Summary of the Invention

[0005] The purpose of this invention is to provide a cutting method for flexible circuit boards. This method is simple and easy to control. By adjusting and controlling the different output power and pulse frequency of the laser beam for different layers to be cut, the cutting effect can be better controlled, avoiding excessive melting of the flexible layer and excessive warping of the metal conductor layer, thereby ensuring the quality and performance of the flexible circuit board.

[0006] To achieve the above objectives, the present invention provides a method for cutting a flexible circuit board, wherein the flexible circuit board includes a first flexible layer, a second flexible layer, and a metal conductor layer located between the first flexible layer and the second flexible layer. The cutting method includes the following steps:

[0007] The first flexible layer is cut by irradiating it with a first laser beam to expose the metal wire layer, wherein the first laser beam has a first output power and a first output pulse frequency;

[0008] The metal wire layer is irradiated and cut using a second laser beam to expose the second flexible layer. The second laser beam has a second output power greater than the first output power and a second output pulse frequency greater than the first output pulse frequency.

[0009] The second flexible layer is cut by irradiating it with a first laser beam.

[0010] Compared with existing technologies, the method of this invention employs a distributed laser cutting method. When cutting the first flexible layer, the laser beam is controlled to have a lower first output power and a lower first output pulse frequency. When cutting the metal conductor layer, the laser beam is controlled to have a higher second output power and a higher second output pulse frequency. When cutting the second flexible layer, the laser beam is controlled to maintain a lower first output power and a lower first output pulse frequency. Thus, different output laser beams are used for different layers of different materials, making the cutting effect more controllable. In other words, this invention achieves optimized cutting results by optimizing and controlling different parameters of the laser beam, thereby avoiding excessive melting of the flexible layer and excessive warping of the metal conductor layer, ensuring the good quality and performance of the flexible circuit board.

[0011] As an example, the first output power is 80-90W, and the first output pulse frequency is 1200-1600kHz.

[0012] As an example, the second output power is 100-120W, and the second output pulse frequency is 2500-3000kHz.

[0013] As an example, the energy of the second laser beam is 3-5 times that of the first laser beam.

[0014] As an example, the energy of the first laser beam is 0.12-0.16 J / mm, and the energy of the second laser beam is 0.45-0.5 J / mm.

[0015] As an example, the wavelength of the first laser beam is 243-455nm.

[0016] As an example, the wavelength of the second laser beam is 532 nm.

[0017] As an example, the cutting speed of the first laser beam and the second laser beam is 100-150 mm / s.

[0018] As an example, the cutting thickness of the first laser beam is 100-250 μm.

[0019] As one embodiment, the cutting thickness of the second laser beam is 0.35-0.40 mm. Detailed Implementation

[0020] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific implementation methods of this application are described in detail below with reference to some embodiments. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0021] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0022] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0023] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0024] The cutting method for flexible circuit boards of the present invention will be further described below with reference to embodiments, but this does not limit the present invention. The method of the present invention aims to provide a cutting method for flexible circuit boards that is simple and easy to control. By adjusting and controlling different output power and pulse frequency of the laser beam for different layers to be cut, the cutting effect can be better controlled, avoiding excessive melting of the flexible layer and excessive warping of the metal conductor layer, thereby ensuring the quality and performance of the flexible circuit board.

[0025] The flexible circuit board of the present invention includes a first flexible layer, a second flexible layer, and a metal conductor layer located between the first flexible layer and the second flexible layer. An embodiment of the cutting method for the flexible circuit board of the present invention includes the following steps:

[0026] A first laser beam is used to irradiate and cut the first flexible layer to expose the metal wire layer. The first laser beam has a first output power and a first output pulse frequency.

[0027] A second laser beam is used to irradiate and cut the metal wire layer to expose the second flexible layer. The second laser beam has a second output power greater than the first output power and a second output pulse frequency greater than the first output pulse frequency.

[0028] The second flexible layer is cut by irradiating it with a first laser beam.

[0029] The method of this invention employs laser cutting. When cutting the first flexible layer, the laser beam is controlled to have a lower first output power and a lower first output pulse frequency. When cutting the metal conductor layer, the laser beam is controlled to have a higher second output power and a higher second output pulse frequency. When cutting the second flexible layer, the laser beam is controlled to maintain a lower first output power and a lower first output pulse frequency. Thus, different output laser beams are used for different layers of different materials, making the cutting effect more controllable. In other words, this invention achieves optimized cutting results by optimizing and controlling different parameters of the laser beam, thereby avoiding excessive melting of the flexible layer and excessive warping of the metal conductor layer, ensuring the good quality and performance of the flexible circuit board.

[0030] In one particular embodiment, the first flexible layer on the surface is first cut, then the metal conductor layer in the middle is cut, and finally the second flexible layer on the bottom surface is cut. Commonly, the first and second flexible layers are PET layers, such as polyethylene terephthalate (PET) material layers. The metal conductor layer is a copper wire layer.

[0031] First, when cutting the first flexible layer, the output power of the first laser beam emitted by the laser is controlled to be 80-90W, and the output pulse frequency is 1200-1600kHz. Optionally, the wavelength of the first laser beam is 243-455nm. The laser beam is used to laser cut along a preset cutting line on the workpiece. For the flexible layer material, the first laser beam is irradiated at an energy of 0.12-0.16J / mm, and the cutting speed is 100-150mm / s. The purpose of this step is to cut the first flexible layer, thereby exposing the metal conductive layer located in the middle layer. Typically, the cutting thickness of the first laser beam is 100-250μm.

[0032] Next, the laser parameters are adjusted so that the second output power of the emitted second laser beam is 100-120W and the second output pulse frequency is 2500-3000kHz, which is much greater than the output parameters of the first laser beam. Preferably, the second laser beam is a green laser with a wavelength of 532nm and a linear polarization state, which is beneficial for cutting the metal conductor layer. More preferably, to achieve optimized cutting results, the energy of the second laser beam is controlled at 0.45-0.5J / mm. Preferably, the energy of the second laser beam is 3-5 times that of the first laser beam. The cutting speed of the second laser beam is adjusted to 100-150mm / s. The second laser beam is used to laser cut along the preset cutting line of the workpiece, thereby cutting the metal conductor layer and exposing the second flexible layer located on the bottom surface. As an embodiment, the cutting thickness of the second laser beam is preferably 0.35-0.40mm.

[0033] Finally, the laser parameters are adjusted to match those of the first laser beam to cut the second flexible layer. Specifically, the output power of the first laser beam emitted by the laser is controlled to be 80-90W, and the output pulse frequency is 1200-1600kHz. Optionally, the wavelength of the first laser beam is 243-455nm. The laser beam is used to cut along a preset cutting line on the workpiece. For the flexible layer material, the first laser beam is irradiated at an energy of 0.12-0.16J / mm, and the cutting speed is 100-150mm / s. The purpose of this step is to cut the second flexible layer, thereby completely separating the flexible circuit board.

[0034] Therefore, through the aforementioned step-by-step laser cutting, excessive melting of the flexible layer and excessive warping of the metal conductor layer can be avoided. For example, the degree of warping can be controlled within the range of 0.10-0.15um, which meets the requirements of the product.

[0035] In summary, the method of this invention employs laser cutting. When cutting the first flexible layer, the laser beam is controlled to have a lower first output power and a lower first output pulse frequency. When cutting the metal conductor layer, the laser beam is controlled to have a higher second output power and a higher second output pulse frequency. When cutting the second flexible layer, the laser beam is controlled to maintain a lower first output power and a lower first output pulse frequency. Thus, different output laser beams are used for different layers of different materials, making the cutting effect more controllable. In other words, this invention achieves optimized cutting results by optimizing and controlling different parameters of the laser beam, thereby avoiding excessive melting of the flexible layer and excessive warping of the metal conductor layer, ensuring the good quality and performance of the flexible circuit board.

[0036] The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, any equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A method for cutting a flexible circuit board, characterized in that, The flexible circuit board includes a first flexible layer, a second flexible layer, and a metal conductor layer located between the first flexible layer and the second flexible layer. The cutting method includes the following steps: A first laser beam is used to irradiate and cut the first flexible layer to expose the metal wire layer, wherein the first laser beam has a first output power and a first output pulse frequency; The metal wire layer is irradiated and cut using a second laser beam to expose the second flexible layer. The second laser beam has a second output power greater than the first output power and a second output pulse frequency greater than the first output pulse frequency. The second flexible layer is cut by irradiating it with a first laser beam.

2. The cutting method for flexible circuit boards as described in claim 1, characterized in that, The first output power is 80-90W, and the first output pulse frequency is 1200-1600kHz.

3. The cutting method for flexible circuit boards as described in claim 1, characterized in that, The second output power is 100-120W, and the second output pulse frequency is 2500-3000kHz.

4. The cutting method for flexible circuit boards as described in claim 1, characterized in that, The energy of the second laser beam is 3-5 times that of the first laser beam.

5. The cutting method for flexible circuit boards as described in claim 1, characterized in that, The energy of the first laser beam is 0.12-0.16 J / mm, and the energy of the second laser beam is 0.45-0.5 J / mm.

6. The cutting method for flexible circuit boards as described in claim 1, characterized in that, The wavelength of the first laser beam is 243-455nm.

7. The cutting method for flexible circuit boards as described in claim 1, characterized in that, The wavelength of the second laser beam is 532nm.

8. The cutting method for flexible circuit boards as described in claim 1, characterized in that, The cutting speed of the first laser beam and the second laser beam is 100-150 mm / s.

9. The cutting method for flexible circuit boards as described in claim 1, characterized in that, The cutting thickness of the first laser beam is 100-250 μm.

10. The cutting method for flexible circuit boards as described in claim 1, characterized in that, The cutting thickness of the second laser beam is 0.35-0.40 mm.