A three-layer LCP antenna structure

Abstract

The utility model discloses a three -layer LCP antenna structure, including shielding layer, cover layer, copper plating layer, LCP double -sided copper -clad plate, adhesive layer and LCP single -sided copper -clad plate, the adhesive layer is low dielectric constant adhesive, LCP double -sided copper -clad plate includes first LCP base material layer and sets up the first copper layer of first LCP base material layer's upper surface, sets up the second copper layer of first LCP base material layer lower surface, and the first copper layer is used to form first circuit layer, and the second copper layer is used to form second circuit layer, and LCP single -layer copper -clad plate includes second LCP base material layer and sets up the third copper layer of second LCP base material layer lower surface, and the third copper layer is used to form third circuit layer, and three -layer circuit is formed through copper plating layer, LCP double -sided copper -clad plate and LCP single -sided copper -clad plate, the utility model discloses the LCP of three -layer circuit replaces traditional cable, utilizes the excellent high -frequency characteristic and low loss feature of LCP material, and promotes the signal transmission performance of antenna.

Description

Technical Field

[0001] This utility model relates to the technical field of antenna structures, and in particular to a three-layer LCP antenna structure. Background Technology

[0002] With the rapid development of 5G communication and millimeter-wave technology, high-end electronic products such as 5G smartphones, high-performance wireless communication modules, and millimeter-wave devices place higher demands on antenna performance. These antennas not only need excellent high-frequency signal transmission capabilities and good signal integrity, but also face strict limitations on size and weight. Traditional antennas, often made of cables or ordinary substrates, suffer from significant dielectric loss and poor signal integrity during high-frequency signal transmission, making them unsuitable for the needs of high-end electronic products.

[0003] Liquid crystal polymers (LCPs) possess advantages such as low dielectric loss, low water absorption, and good high-frequency performance, making them promising candidates for high-frequency antennas. However, existing multilayer LCP antenna structures still have shortcomings in interlayer connections, circuit layout, aperture design, and EMI shielding, resulting in significant signal loss and poor transmission performance, failing to fully meet the needs of high-end electronic products. Therefore, there is an urgent need to design a novel multilayer LCP antenna structure to reduce signal loss and improve signal transmission performance.

[0004] In view of this, this utility model is developed by deeply conceiving and actively researching and improving the numerous shortcomings and inconveniences caused by the imperfections in the existing antenna structure design. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a three-layer LCP antenna structure that can improve antenna signal transmission performance and reduce signal loss.

[0006] To achieve the above objectives, the solution of this utility model is: A three-layer LCP antenna structure is characterized by comprising, from top to bottom, a first EMI shielding layer, a first cover layer, a first electroplated copper layer, an LCP double-sided copper clad laminate, a first adhesive layer, an LCP single-sided copper clad laminate, a second electroplated copper layer, a second cover layer, and a second EMI shielding layer. The first adhesive layer is a low dielectric constant adhesive. The LCP double-sided copper clad laminate includes a first LCP substrate layer and a first copper layer disposed on the upper surface of the first LCP substrate layer and a second copper layer disposed on the lower surface of the first LCP substrate layer. The first copper layer is used to form a first circuit layer, and the second copper layer is used to form a second circuit layer. The LCP single-sided copper clad laminate includes a second LCP substrate layer and a third copper layer disposed on the lower surface of the second LCP substrate layer. The third copper layer is used to form a third circuit layer. The three-layer circuit is formed by the first electroplated copper layer, the LCP double-sided copper clad laminate, the LCP single-sided copper clad laminate, and the second electroplated copper layer.

[0007] Furthermore, the first cover layer and the second cover layer include a PI substrate and an adhesive. One side of the PI substrate is connected to the EMI shielding layer. The adhesive of the first cover layer connects the PI substrate and the first electroplated copper layer. The adhesive of the second cover layer connects the PI substrate and the second electroplated copper layer.

[0008] Furthermore, the thicknesses of the first EMI shielding layer and the second EMI shielding layer are 46 μm, the thicknesses of the first cover layer and the second cover layer are 27.5 μm, the sum of the thicknesses of the first electroplated copper layer and the first copper layer of the LCP double-sided copper clad laminate is 22 μm, the thickness of the second electroplated copper layer and the third copper layer of the LCP single-sided copper clad laminate is 22 μm, the thicknesses of the first LCP substrate layer and the second LCP substrate layer are 100 μm, the thickness of the second copper layer of the LCP double-sided copper clad laminate is 12 μm, and the thickness of the first adhesive layer is 25 μm.

[0009] Furthermore, the PI substrates of the first and second cover layers are 12.5 μm thick, and the adhesives of the first and second cover layers are 15 μm thick.

[0010] Furthermore, the three-layer LCP antenna structure is characterized by including through holes and blind holes. The diameter of the through holes is 0.15 mm, and the blind holes include an upper blind hole and a lower blind hole. The diameter of the upper blind hole is 0.15 mm, the diameter of the lower blind hole is 0.125 mm, and the aspect ratio of the blind holes is 0.993.

[0011] Furthermore, the impedance of the described three-layer LCP antenna structure is 50±2.5Ω.

[0012] Furthermore, the first EMI shielding layer and the second EMI shielding layer are metallized layers with electromagnetic interference shielding function.

[0013] With the above structure, the three-layer LCP antenna structure of this utility model uses LCP material as the core substrate, and utilizes its characteristics of low dielectric loss, low water absorption and good high-frequency performance to effectively improve the high-frequency signal transmission capability and signal integrity; by rationally designing the structure of each layer and combining it with low dielectric constant adhesive, signal loss is further reduced; the setting of the EMI shielding layer improves the antenna's anti-electromagnetic interference capability; it is suitable for high-end electronic products such as 5G smartphones, high-performance wireless communication modules, and millimeter-wave devices.

[0014] This invention uses a three-layer LCP to replace traditional cables, utilizing the excellent high-frequency characteristics and low-loss properties of LCP material to improve the antenna's signal transmission performance. The reasonable material stacking structure and aperture and impedance design enhance the antenna's stability and anti-interference ability, effectively solving the problems of high dielectric loss and poor signal integrity in traditional antennas during high-frequency signal transmission. It has the advantages of effectively reducing signal loss and improving high-frequency signal transmission capability and signal integrity. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the layer structure of this utility model.

[0016] Figure 2 This is a schematic diagram of the appearance of one embodiment of the present utility model. Detailed Implementation

[0017] To further explain the technical solution of this utility model, the following detailed description is provided through specific embodiments.

[0018] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0019] like Figure 1 and Figure 2As shown, this utility model discloses a three-layer LCP antenna structure, which includes, from top to bottom, a first EMI shielding layer 1, a first cover layer 2, a first electroplated copper layer 3, an LCP double-sided copper clad laminate 4, a first adhesive layer 5, an LCP single-sided copper clad laminate 6, a second electroplated copper layer 7, a second cover layer 8, and a second EMI shielding layer 9. The first adhesive layer 5 is a low dielectric constant adhesive with a dielectric constant ≤ 2.8. For example, Panasonic's R-BM17 low dielectric constant adhesive can be used. The LCP double-sided copper clad laminate 4 includes a first EMI shielding layer 1, a first cover layer 2, a first electroplated copper layer 3, a first electroplated copper layer 4, a first EMI shielding layer 5, a first cover layer 6, a second EMI shielding layer 7, a second cover layer 8, and a second EMI shielding layer 9. The first adhesive layer 5 is a low dielectric constant adhesive with a dielectric constant ≤ 2.8. For example, Panasonic's R-BM17 low dielectric constant adhesive can be used. The LCP double-sided copper clad laminate 4 includes a first EMI shielding layer 1, a first cover layer 2, a first electroplated copper layer 3, a first electroplated copper layer 4, a second cover layer 5, a second EMI shielding layer 6, a first EMI shielding layer 7, a second EMI shielding layer 8, and a second EMI shielding layer 9. The first LCP substrate layer 41 includes a first copper layer 42 disposed on the upper surface of the first LCP substrate layer 41 and a second copper layer 43 disposed on the lower surface of the first LCP substrate layer 41. The first copper layer 42 is used to form a first circuit layer, and the second copper layer 43 is used to form a second circuit layer. The LCP single-layer copper clad laminate 6 includes a second LCP substrate layer 61 and a third copper layer 62 disposed on the lower surface of the second LCP substrate layer 61. The third copper layer 62 is used to form a third circuit layer. A three-layer circuit is formed by the first electroplated copper layer 3, the LCP double-sided copper clad laminate 4, the LCP single-sided copper clad laminate 6 and the second electroplated copper layer 7.

[0020] This invention proposes an antenna design scheme incorporating a multi-layer composite structure. The three-layer circuit layout shortens the signal transmission path. LCP material is used as the core substrate, leveraging its low dielectric loss, low water absorption, and excellent high-frequency performance to effectively improve high-frequency signal transmission capability and signal integrity. The stacking of LCP double-sided copper-clad laminate 4 and LCP single-layer copper-clad laminate 6 forms a stepped impedance transition structure, solving the impedance matching problem between different copper layers. The LCP double-sided copper-clad laminate 4 and LCP single-layer copper-clad laminate 6 are bonded together using a low-dielectric-constant adhesive. This low-dielectric-constant adhesive is specifically designed for high-frequency signal transmission and highly integrated electronic devices, improving performance by reducing signal delay and energy loss. The low dielectric constant effectively reduces interlayer dielectric loss, enhancing high-frequency signal transmission. Signal continuity is achieved between the three layers through electroplated vias and blind vias. A first EMI shielding layer 1 and a second EMI shielding layer 9 are distributed on the upper and lower surfaces of the structure, effectively isolating external electromagnetic interference.

[0021] The first EMI shielding layer 1 and the second EMI shielding layer 9 are metallized layers with electromagnetic interference shielding function. Specifically, they can be achieved by forming a copper-nickel alloy plating layer using a vacuum sputtering process. The first EMI shielding layer 1 and the second EMI shielding layer 9 can effectively isolate external electromagnetic interference.

[0022] The first cover layer 2 and the second cover layer 8 include PI substrates 21 and 81 and adhesives 22 and 82. One side of the PI substrates 21 and 81 is connected to the EMI shielding layers 1 and 9. The adhesive 22 of the first cover layer 2 connects the PI substrate 21 and the first electroplated copper layer 3, and the adhesive 82 of the second cover layer 8 connects the PI substrate 81 and the second electroplated copper layer 7. The PI substrates 21 and 81 provide mechanical support for the cover layers and maintain the stability of high-frequency signal transmission. The first cover layer 2 and the second cover layer 8 are in direct contact with the first EMI shielding layer 1 and the second EMI shielding layer 9 through the PI substrates 21 and 81, using the PI substrates to maintain structural stability. At the same time, the adhesives 22 and 82 tightly bond the first electroplated copper layer 3 and the second electroplated copper layer 7 to the PI substrates 21 and 81. After curing, the adhesives 22 and 82 form a uniform bonding interface, avoiding signal reflection or loss caused by interlayer gaps. In this embodiment, the thicknesses of the first EMI shielding layer 1 and the second EMI shielding layer 9 are 46 μm, respectively. The first EMI shielding layer 1 and the second EMI shielding layer 9 can reflect, absorb or attenuate electromagnetic interference signals, reduce the impact of external electromagnetic interference on the internal signal transmission of the antenna, and at the same time reduce the interference of the antenna's own signal to the outside world, ensuring that the antenna can still transmit signals stably in complex electromagnetic environments. The thicknesses of the first cover layer 2 and the second cover layer 8 are 27.5 μm each. The combined thickness of the first electroplated copper layer 7 and the first copper layer 42 of the LCP double-sided copper clad laminate 4 is 22 μm. The combined thickness of the second electroplated copper layer 7 and the third copper layer 62 of the LCP single-sided copper clad laminate 6 is 22 μm. This copper layer thickness design ensures conductivity while also controlling the antenna's weight. The thicknesses of the first LCP substrate layer 41 and the second LCP substrate layer 61 are 100 μm each, providing stable substrate support for the antenna. The second copper layer 43 of the LCP double-sided copper clad laminate 4 is 12 μm thick. The thickness of the first adhesive layer 5 is 25 μm. The thicknesses of the PI substrates 21 and 81 of the first cover layer 2 and the second cover layer 8 are 12.5 μm each. The material has good insulation and high temperature resistance, which can achieve interlayer insulation, protect the internal structure of the antenna, prevent the external environment from damaging the internal structure of the antenna, and extend the service life of the antenna; the adhesives 22 and 83 of the first cover layer 2 and the second cover layer 8 are 15um thick. The adhesives 22 and 83 are used to achieve tight bonding between the upper and lower layers of materials, ensuring the integrity of the antenna structure.

[0023] The antenna has an overall thickness of 428µm, which meets the size requirements for antennas in high-end electronic products.

[0024] The three-layer LCP antenna structure described in this utility model has through holes and blind holes. The diameter of the through holes is 0.15 mm, and the blind holes include an upper blind hole and a lower blind hole. The diameter of the upper blind hole is 0.15 mm, and the diameter of the lower blind hole is 0.125 mm. The aspect ratio of the blind holes is 0.993. The design of the diameter of the through holes and blind holes, as well as the aspect ratio of the blind holes, can realize reliable electrical connection between different layers of the antenna and ensure stable signal transmission.

[0025] The antenna structure impedance is 50±2.5Ω, which can reduce signal reflection and improve signal transmission efficiency.

[0026] The above embodiments and figures are not intended to limit the product form and style of this utility model. Any appropriate changes or modifications made by those skilled in the art should be considered as not departing from the patent scope of this utility model.

Claims

1. A three-layer LCP antenna structure, characterized in that: The system comprises, from top to bottom, a first EMI shielding layer, a first cover layer, a first electroplated copper layer, an LCP double-sided copper clad laminate, a first adhesive layer, an LCP single-sided copper clad laminate, a second electroplated copper layer, a second cover layer, and a second EMI shielding layer. The first adhesive layer is a low dielectric constant adhesive. The LCP double-sided copper clad laminate includes a first LCP substrate layer and a first copper layer disposed on the upper surface of the first LCP substrate layer and a second copper layer disposed on the lower surface of the first LCP substrate layer. The first copper layer is used to form a first circuit layer, and the second copper layer is used to form a second circuit layer. The LCP single-sided copper clad laminate includes a second LCP substrate layer and a third copper layer disposed on the lower surface of the second LCP substrate layer. The third copper layer is used to form a third circuit layer. A three-layer circuit is formed by the first electroplated copper layer, the LCP double-sided copper clad laminate, the LCP single-sided copper clad laminate, and the second electroplated copper layer.

2. The three-layer LCP antenna structure as described in claim 1, characterized in that: The first cover layer and the second cover layer have the same structure, each including a PI substrate and an adhesive. One side of the PI substrate is connected to the EMI shielding layer. The adhesive of the first cover layer connects the PI substrate and the first electroplated copper layer. The adhesive of the second cover layer connects the PI substrate and the second electroplated copper layer.

3. The three-layer LCP antenna structure as described in claim 1, characterized in that: The thicknesses of the first EMI shielding layer and the second EMI shielding layer are 46 μm, the thicknesses of the first cover layer and the second cover layer are 27.5 μm, the sum of the thicknesses of the first electroplated copper layer and the first copper layer of the LCP double-sided copper clad laminate is 22 μm, the thickness of the second electroplated copper layer and the third copper layer of the LCP single-sided copper clad laminate is 22 μm, the thicknesses of the first LCP substrate layer and the second LCP substrate layer are 100 μm, the thickness of the second copper layer of the LCP double-sided copper clad laminate is 12 μm, and the thickness of the first adhesive layer is 25 μm.

4. The three-layer LCP antenna structure as described in claim 2, characterized in that: The PI substrates of the first and second cover layers are 12.5 μm thick, and the adhesives of the first and second cover layers are 15 μm thick.

5. A three-layer LCP antenna structure as described in any one of claims 1 to 4, characterized in that: It includes through holes and blind holes. The diameter of the through holes is 0.15 mm. The blind holes include upper blind holes and lower blind holes. The diameter of the upper blind hole is 0.15 mm and the diameter of the lower blind hole is 0.125 mm. The aspect ratio of the blind holes is 0.

993.

6. The three-layer LCP antenna structure as described in claim 1, characterized in that: The impedance of the antenna structure is 50±2.5Ω.

7. The three-layer LCP antenna structure as described in claim 1, characterized in that: The first EMI shielding layer and the second EMI shielding layer are metallized layers with electromagnetic interference shielding function.

Images