5g ceramic dielectric filter femtosecond laser drilling device and method

Abstract

The application belongs to the technical field of laser drilling, and provides a 5G ceramic medium filter femtosecond laser drilling device and method, which comprises a femtosecond laser, and a pulse energy adjusting and controlling system, a laser pulse shaping system and a laser rotary drilling system arranged on the light beam path of the femtosecond laser. The femtosecond laser is used as a drilling light beam, has the advantages of high peak power, short action time, low material processing threshold and micron-level focused light spot, etc., can avoid the melting of the 5G ceramic medium filter material, instantaneously change the material on the 5G ceramic medium filter into plasma and emit it away, realize drilling in a very short time when heat has no time to transfer between electrons and lattices in the 5G ceramic medium filter material, and avoid the generation of thermal effects.

Description

A femtosecond laser drilling device and method for 5G ceramic dielectric filters Technical Field

[0001] This invention belongs to the field of laser drilling technology, and particularly relates to a femtosecond laser drilling device and method for 5G ceramic dielectric filters. Background Technology

[0002] The application of ceramic dielectric filters in the 5G field has very strict requirements for drilling quality and consistency. Traditional machining and long-pulse laser processing can no longer meet the production requirements.

[0003] The inventors discovered that ceramic dielectric materials used in 5G filters possess characteristics such as high melting point, high hardness, corrosion resistance, and fragility. 5G filters require drilling with high aspect ratios, no taper, high quality, and high consistency. In practical applications, traditional methods have certain limitations in processing high-quality micro-holes. Among common micro-hole processing methods, electron beam processing and focused ion beam processing have harsh operating conditions, low efficiency, and expensive equipment; electrical discharge etching can only process conductive materials; electrochemical drilling has extremely low efficiency and material limitations; and mechanical drilling is difficult to process harder materials and has a small aspect ratio. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes a femtosecond laser drilling device and method for 5G ceramic dielectric filters. Compared with traditional processing methods, this invention can improve drilling quality and can process microholes with high aspect ratio, no taper, high quality, and high consistency on 5G ceramic dielectric filters, thereby improving product processing efficiency and precision.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a femtosecond laser drilling device for 5G ceramic dielectric filters, employing the following technical solution:

[0006] A femtosecond laser drilling device for 5G ceramic dielectric filters includes a femtosecond laser, a pulse energy adjustment and control system, a laser pulse shaping system, and a laser rotation drilling system disposed on the path of the emitted beam of the femtosecond laser.

[0007] Furthermore, a beam isolation device and a beam expander assembly are provided between the femtosecond laser and the pulse energy adjustment and control system, with the beam isolation device located close to the femtosecond laser.

[0008] Furthermore, a first reflecting mirror is disposed between the femtosecond laser and the beam isolation device, and a second reflecting mirror is disposed between the beam isolation device and the beam expander group; the incident light and the outgoing light of the first reflecting mirror are perpendicular, and the incident light and the outgoing light of the second reflecting mirror are perpendicular.

[0009] Furthermore, the pulse energy adjustment and control system includes a half-wave plate and a polarizing beam splitter.

[0010] Furthermore, the laser pulse shaping system includes a spatial light modulator and a lens group.

[0011] Furthermore, the laser rotary drilling system includes a two-dimensional galvanometer, a rotating prism, and a focusing lens group.

[0012] Furthermore, a motion platform is provided in the direction of the emitted light beam of the laser rotary drilling system.

[0013] To achieve the above objectives, in a second aspect, the present invention also provides a femtosecond laser drilling method for 5G ceramic dielectric filters, employing the following technical solution:

[0014] A femtosecond laser drilling method for 5G ceramic dielectric filters is provided, which employs the 5G ceramic dielectric filter femtosecond laser drilling device as described in the first aspect.

[0015] Furthermore, the femtosecond laser emitted by the femtosecond laser first undergoes energy adjustment of the focused spot through a pulse energy adjustment and control system, then the Gaussian spot emitted by the femtosecond laser is shaped into a flat-top spot through a laser pulse shaping system, and finally the angle between the focused beam and the 5G ceramic dielectric filter is adjusted by a laser rotation drilling system before drilling.

[0016] Furthermore, when the linearly polarized light output from the femtosecond laser passes through the half-wave plate, the polarization direction of the linearly polarized light is changed. The polarization beam splitter splits the linearly polarized light into two beams, S-beam and P-beam, with mutually perpendicular vibration directions. The P-beam continues to propagate along the original propagation direction, while the S-beam exits from the other side of the polarization beam splitter. The energy of the focused spot is adjusted by rotating the half-wave plate 8.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] 1. This invention employs a femtosecond laser. The femtosecond laser emits extremely short pulses. First, the energy of the focused spot is adjusted by a pulse energy adjustment and control system. Then, a laser pulse shaping system shapes the Gaussian spot emitted by the femtosecond laser into a flat-top spot. Finally, a laser rotation drilling system adjusts the angle between the focused beam and the 5G ceramic dielectric filter before drilling. The femtosecond laser, as the drilling beam, has advantages such as high peak power, short action time, low material processing threshold, and a focused spot size of only micrometers. It can instantly turn the material on the 5G ceramic dielectric filter into plasma and evaporate it without melting the material. This achieves drilling in a very short time, before heat can be transferred between electrons and the lattice within the 5G ceramic dielectric filter material, thus avoiding the generation of thermal effects.

[0019] 2. Femtosecond lasers, as drilling beams, have extremely high peak power density, enabling precise control over processing dimensional accuracy, shape accuracy, and consistency. The use of femtosecond lasers to process 5G ceramic dielectric filters has a very promising application prospect in industrial production. Attached Figure Description

[0020] The accompanying drawings, which form part of this embodiment, are used to provide a further understanding of this embodiment. The illustrative embodiments and their descriptions are used to explain this embodiment and do not constitute an improper limitation of this embodiment.

[0021] Figure 1 is a structural schematic diagram of Embodiment 1 of the present invention;

[0022] The components include: 1. Femtosecond laser; 2. First reflector; 3. Beam isolation device; 4. Second reflector; 5. Beam expander group; 6. Pulse energy adjustment and control system; 7. Laser pulse shaping system; 8. Half-wave plate; 9. Polarizing beam splitter; 10. Spatial light modulator; 11. Lens group; 12. Laser rotating drilling system; 13. Two-dimensional galvanometer; 14. Rotating prism; 15. 5G ceramic dielectric filter; 16. Motion platform; 17. Focusing lens group; 18. Collimated beam; 19. Flat-top beam. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0024] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0025] Example 1:

[0026] As shown in Figure 1, this embodiment provides a femtosecond laser drilling device for 5G ceramic dielectric filters, including an ultrafast laser, and a first reflector 2, a beam isolation device 3, a second reflector 4, a beam expander group 5, a pulse energy adjustment and control system 6, a laser pulse shaping system 7, a laser rotation drilling system 12, and a motion platform 16 disposed on the path of the emitted beam of the ultrafast laser.

[0027] To meet the requirements of 5G filters for high aspect ratio, no taper, high quality, and high consistency in drilling, and to address the problems associated with traditional drilling methods, this embodiment provides a femtosecond laser drilling device for 5G ceramic dielectric filters. Using a femtosecond laser as the drilling beam, it offers advantages such as high peak power, short processing time, low material processing threshold, and a focused spot size of only micrometers. It can instantly transform the material on the 5G ceramic dielectric filter into plasma and evaporate it without melting the material. This allows for drilling within a very short time, before heat can be transferred between electrons and the crystal lattice within the 5G ceramic dielectric filter material, thus avoiding thermal effects. Compared to traditional processing methods, this improves drilling quality and enables the fabrication of micro-holes with high aspect ratio, no taper, high quality, and high consistency on 5G ceramic dielectric filters, thereby improving the processing efficiency and accuracy of 5G ceramic dielectric filters.

[0028] The pulse energy adjustment and control system 6 includes a half-wave plate 8 and a polarizing beam splitter 9; the laser pulse shaping system 7 includes a spatial light modulator 10 and a lens group 11; the laser rotating drilling system 12 includes a two-dimensional galvanometer 13, a rotating prism 14 and a focusing lens group 17; the motion platform 16 is used to place or install and fix the 5G ceramic dielectric filter 15; the two-dimensional galvanometer 13 can be configured as a two-dimensional reflector group.

[0029] A first reflecting mirror 2 is disposed between the femtosecond laser 1 and the beam isolation device 3, and a second reflecting mirror 4 is disposed between the beam isolation device 3 and the beam expander group 5. The incident and outgoing light rays of the first reflecting mirror 1 are perpendicular, and the incident and outgoing light rays of the second reflecting mirror 4 are perpendicular. The arrangement of the first reflecting mirror 1 and the second reflecting mirror 4 can reduce the overall length of the drilling device by changing the direction of the beam, which is beneficial to the optimized design and subsequent promotion of the drilling device.

[0030] The ultrafast laser can be configured as a femtosecond laser 1; the ultrafast laser emitted by the femtosecond laser 1 can be a femtosecond infrared laser, a femtosecond green laser, or a femtosecond ultraviolet laser, and the output beam is a linearly polarized light with a pulse width on the order of femtoseconds and a Gaussian beam.

[0031] The beam isolation device 3 can be a beam isolator with an isolation degree greater than 30dB, used to isolate the influence of the laser beam reflected in the drilling optical path on the stability of the laser output energy.

[0032] The pulse energy adjustment and control system 6 is used to adjust the energy of the focused spot. When the linearly polarized light output by the femtosecond laser 1 passes through the half-wave plate 8, the polarization direction of the linear polarization will be changed. The polarization beam splitter 9 can split the linearly polarized light into two beams, S-beam and P-beam, with mutually perpendicular vibration directions. The P-beam continues to propagate along the original propagation direction, while the S-beam exits from the other side of the polarization beam splitter 9. The energy of the focused spot can be adjusted by rotating the half-wave plate 8.

[0033] The laser pulse shaping system 7 is used to shape the Gaussian spot emitted by the femtosecond laser 1 into a flat-top spot; wherein, the spatial light modulator 10 is used to shape the Gaussian beam incident on the spatial light modulator 10 into a flat-top beam 19 through phase modulation; the flat-top beam 19 passes through a lens group 11 composed of two relay lenses, and after the lens group 11 performs Fourier transform and transmission on the flat-top beam 19, it is introduced into the laser rotating drilling system 12;

[0034] The laser rotary drilling system 12 is used to change the angle between the focused beam and the 5G ceramic medium drilling material. By changing the angle, a high aspect ratio non-tapered hole can be obtained, thus achieving a high-quality drilling effect. Rotary drilling can be achieved by controlling the position and angle of the beam through the rotating prism 14 synchronously scanning the two-dimensional reflector group.

[0035] The motion platform 16 is a high-precision positioning motion platform with a positioning accuracy within 2 micrometers. The motion platform 16 can move in space in three directions: x, y, and z. It is used to adjust the relative position of the 5G ceramic dielectric filter and the laser focus. While performing rotary drilling, the focus moves up and down on the workpiece to ensure that the laser focus is on the surface of the 5G ceramic dielectric filter during each rotary drilling, thereby accurately controlling the processing dimensional accuracy and drilling consistency.

[0036] The ceramic dielectric material in the 5G ceramic dielectric filter 15 can be set as alumina (Al2O3), aluminum nitride (AlN), or zirconium oxide, etc.

[0037] The drilling method based on the femtosecond laser drilling device for 5G ceramic dielectric filters in this embodiment includes:

[0038] The femtosecond laser 1 emits ultrashort pulse lasers. After passing through the emission direction of the femtosecond laser 1, the ultrashort pulse laser is sequentially connected to the beam isolation device 3, the pulse energy adjustment and control system 6, and the laser pulse shaping system 7. The position and angle of the beam are controlled by the rotating prism synchronously scanning the two-dimensional reflector group in the laser rotating drilling system 12, achieving laser rotating drilling. Specifically, the beam expander group 5 can be manually or electrically adjusted to obtain a collimated beam 18 by adjusting its magnification and far-field divergence angle. The collimated beam 18 sequentially enters the pulse energy adjustment and control system 6. By manually or electrically controlling the rotation angle of the half-wave plate, the polarization beam splitter 9 splits the linearly polarized light of the collimated beam 18 into two beams, S-beam and P-beam, with mutually perpendicular vibration directions. The P-beam continues to propagate along its original propagation direction and enters the laser pulse shaping system 7. The spatial light modulator 10 and the lens group 11 shape the Gaussian spot emitted by the ultrafast laser 1 into a flat-top beam 19. The flat-top beam 19 is then guided into the laser... The optical rotary drilling system 12 uses a beam angle and motion control system composed of the two-dimensional galvanometer 13 to generate beam deflection. Finally, the beam is focused by the rotating prism 14 and the focusing lens group 17 and reaches the surface of the 5G ceramic dielectric filter 15. The size of the hole can be controlled by controlling the rotation scanning angle of the two-dimensional galvanometer. The flat-top beam 19 forms micro-holes on the surface of the 5G ceramic dielectric filter 15 through ablation. The movement of the xy axis in the motion platform 16 can complete the positioning of the drilling position of the 5G ceramic dielectric filter, and the movement of the z axis can realize the relative movement of the laser focus and the position of the 5G ceramic dielectric filter. In this way, taperless drilling that requires focus movement can be achieved.

[0039] Femtosecond lasers are lasers with extremely short pulses, high peak power, short duration, low material processing threshold, and focused spot size only at the micrometer level. They can instantly turn materials into plasma and evaporate them without melting them. In this extremely short time, heat cannot be transferred between electrons and the crystal lattice within the material, thus avoiding thermal effects. Due to the extremely high peak power density, it is possible to control the processing dimensional accuracy, shape accuracy, and consistency very precisely. The use of femtosecond lasers to process 5G ceramic dielectric filters has a very promising application prospect in industrial production.

[0040] Example 2:

[0041] This embodiment provides a femtosecond laser drilling method for 5G ceramic dielectric filters, employing the femtosecond laser drilling device for 5G ceramic dielectric filters as described in Embodiment 1. Specifically, the femtosecond laser emitted by the femtosecond laser is first focused by a pulse energy adjustment and control system to adjust the energy of the focused spot, then the Gaussian spot emitted by the femtosecond laser is shaped into a flat-top spot by a laser pulse shaping system, and finally the angle between the focused beam and the 5G ceramic dielectric filter is adjusted by a laser rotation drilling system before drilling.

[0042] When the linearly polarized light output from the femtosecond laser passes through a half-wave plate, the polarization direction of the linearly polarized light is changed. The polarization beam splitter splits the linearly polarized light into two beams, S-beam and P-beam, with their vibration directions perpendicular to each other. The P-beam continues to propagate along its original direction, while the S-beam exits from the other side of the polarization beam splitter. The energy of the focused spot is adjusted by rotating the half-wave plate 8.

[0043] The above description is merely a preferred embodiment of this practice and is not intended to limit the scope of this practice. Various modifications and variations can be made to this practice by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this practice should be included within the protection scope of this practice.

Claims

1. A femtosecond laser drilling device for 5G ceramic dielectric filters, characterized in that, The system includes a femtosecond laser, and a pulse energy adjustment and control system, a laser pulse shaping system, and a laser rotating drilling system disposed along the beam path of the femtosecond laser. A beam isolation device and a beam expander assembly are disposed between the femtosecond laser and the pulse energy adjustment and control system, with the beam isolation device close to the femtosecond laser. The laser rotating drilling system includes a two-dimensional galvanometer, and the size of the hole can be controlled by controlling the rotation scanning angle of the galvanometer. A motion platform is disposed in the direction of the emitted light beam of the laser rotating drilling system. The xy-axis movement of the motion platform can locate the drilling position of the 5G ceramic dielectric filter, and the z-axis movement of the motion platform can realize the relative movement between the laser focus and the position of the 5G ceramic dielectric filter. The flat-top beam output by the laser pulse shaping system forms micro-holes on the surface of the 5G ceramic dielectric filter through ablation. The pulse energy adjustment and control system includes a half-wave plate and a polarizing beam splitter. The laser pulse shaping system includes a spatial light modulator and a lens assembly. The laser rotating drilling system also includes a rotating prism and a focusing lens assembly.

2. The femtosecond laser drilling device for a 5G ceramic dielectric filter as described in claim 1, characterized in that, A first reflecting mirror is disposed between the femtosecond laser and the beam isolation device, and a second reflecting mirror is disposed between the beam isolation device and the beam expander group; the incident light and the outgoing light of the first reflecting mirror are perpendicular, and the incident light and the outgoing light of the second reflecting mirror are perpendicular.

3. A femtosecond laser drilling method for 5G ceramic dielectric filters, characterized in that, The 5G ceramic dielectric filter femtosecond laser drilling device as described in any one of claims 1-2 was adopted.

4. The femtosecond laser drilling method for a 5G ceramic dielectric filter as described in claim 3, characterized in that, The femtosecond laser emitted by the femtosecond laser first undergoes energy adjustment of the focused spot through a pulse energy adjustment and control system. Then, the Gaussian spot emitted by the femtosecond laser is shaped into a flat-top spot through a laser pulse shaping system. Finally, the angle between the focused beam and the 5G ceramic dielectric filter is adjusted by a laser rotation drilling system before drilling.

5. The femtosecond laser drilling method for a 5G ceramic dielectric filter as described in claim 3, characterized in that, When the linearly polarized light output from the femtosecond laser passes through a half-wave plate, the polarization direction of the linearly polarized light is changed. A polarizing beam splitter splits the linearly polarized light into two beams, S-beam and P-beam, with their vibration directions perpendicular to each other. The P-beam continues to propagate along its original direction, while the S-beam exits from the other side of the polarizing beam splitter. The energy of the focused spot is adjusted by rotating the half-wave plate.

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