Conductive connector and mobile terminal

Abstract

This application provides a conductive connector and a mobile terminal. The conductive connector includes foam and a film structure, with the film structure wrapping around the periphery of the foam. In this application, the film structure includes a metal layer and an insulating film, with the insulating film at least covering the surface of the metal layer facing away from the foam. Furthermore, the relative permittivity of the insulating film is greater than 1. Using the conductive connector design provided in this application, since the insulating film covers the surface of the metal layer facing away from the foam, when applied between two electrical connection surfaces, direct contact between the metal layer and the electrical connection surface can be effectively avoided. Instead, a coupling capacitance is generated between the metal layer and the electrical connection surface, thereby achieving a coupled electrical connection between the electrical connection surfaces, which is beneficial for improving the reliability of the electrical connection between the electrical connection surfaces.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to a conductive connector and a mobile terminal. Background Technology

[0002] As mobile terminals become smaller and thinner, higher demands are placed on the miniaturization of antenna grounding solutions. Currently, antenna grounding is mostly achieved through the electrical connection between the display screen's grounding layer and the ground plane. Therefore, while achieving the electrical connection between the display screen's grounding layer and the ground plane, issues such as stress and passive intermodulation must also be considered to reduce the risk of display screen printing while meeting the communication requirements of mobile terminals. Summary of the Invention

[0003] This application provides a conductive connector and a mobile terminal, which can achieve a miniaturized design of the mobile terminal while meeting the communication and display requirements of the mobile terminal.

[0004] Firstly, this application provides a conductive connector comprising foam and a film structure, the film structure being wrapped around the periphery of the foam. In this application, the film structure includes a metal layer and an insulating film, the insulating film at least covering the surface of the metal layer facing away from the foam, and the relative permittivity of the insulating film is greater than 1. Using the conductive connector design provided in this application, since the insulating film covers the surface of the metal layer facing away from the foam, when applied between two electrical connection surfaces, direct contact between the metal layer and the electrical connection surface can be effectively avoided. Instead, a coupling capacitance is generated between the metal layer and the electrical connection surface, thereby achieving a coupled electrical connection between the electrical connection surfaces, which is beneficial for improving the reliability of the electrical connection between the electrical connection surfaces.

[0005] In one possible implementation of this application, along the stacking direction from the metal layer to the insulating film, the projection of the metal layer falls within the outline of the projection of the insulating film. This effectively prevents the edges of the metal layer from being exposed outside the insulating film. Therefore, when this conductive connector is applied between two electrical connection surfaces, the risk of direct contact between the metal layer and the electrical connection surface can be effectively reduced, thereby ensuring the reliability of the coupling electrical connection between the two electrical connection surfaces.

[0006] Furthermore, the distance d1 between the edge of the metal layer's projection and the edge of the insulating film's projection satisfies the following condition with respect to the dimension D1 of the insulating layer in the first direction: 1% × D1 ≤ D1 - d1 ≤ 10% × D1, where the first direction is the direction containing the minimum distance d1. Thus, in the aforementioned stacking direction, the projection of the metal layer is contained within the outline edge of the insulating film's projection, ensuring the insulation of the outer surface of the conductive connector.

[0007] In one possible implementation of this application, the film structure further includes a substrate layer, which is an insulating material layer. Additionally, a metal layer is located between the substrate layer and the insulating film. This improves the structural reliability of the conductive connector.

[0008] In this application, along the stacking direction from the metal layer to the substrate layer, the projection of the metal layer falls within the outline of the projection of the substrate layer, and the insulating film covers the edge of the metal layer. That is, the metal layer is encased by the insulating film and the substrate layer to reduce the exposed portion of the metal layer, thereby ensuring the insulation of the outer surface of the conductive connector. Thus, when this conductive connector is applied between two electrical connection surfaces, the risk of direct contact between the metal layer and the electrical connection surface can be further reduced, thereby ensuring the reliability of the coupling electrical connection between the two electrical connection surfaces.

[0009] Furthermore, the minimum distance d2 between the edge of the metal layer's projection and the edge of the substrate layer's projection satisfies the following condition with respect to the dimension D2 of the substrate layer's projection in the second direction: 1% × D2 ≤ D2 - d2 ≤ 10% × D2, where the second direction is the direction containing the minimum distance d2. This allows the insulating film and substrate layer to completely enclose the metal layer, reducing the risk of metal layer exposure. Therefore, when this conductive connector is applied between two electrical connection surfaces, the risk of direct contact between the metal layer and the electrical connection surface can be further reduced, thereby ensuring the reliability of the coupling electrical connection between the two electrical connection surfaces.

[0010] In one possible implementation of this application, the thickness h1 of the insulating film satisfies: 0.2 μm ≤ h1 ≤ 5 μm. This avoids the risk of metal layer exposure due to insufficient insulating film thickness; and also avoids the difficulty in generating sufficient coupling capacitance between the metal layer and the electrical connection surface due to excessive insulating film thickness. Therefore, selecting the insulating film thickness within the above range can avoid direct contact between the metal layer and the electrical connection surface while forming a larger coupling capacitance, thereby satisfying the requirements for coupling electrical connection between the two electrical connection surfaces.

[0011] In addition, the relative permittivity ε of the insulating film satisfies: ε ≥ 1.5. This ensures a large coupling capacitance between the metal layer of the conductive connector and the electrical connection surface, thereby meeting the coupling electrical connection requirements between the electrical connection surfaces.

[0012] Since the conductive connector provided in this application is applied between two electrical connection surfaces, the surface of the insulating film is in contact with the electrical connection surface. To ensure the tightness of the adhesion between the surface of the insulating film and the electrical connection surface, the surface roughness of the insulating film can be less than 1 μm. This allows for the coupling of a coupling capacitor that meets the usage requirements between the metal layer and the conductive connection surface.

[0013] In this application, the thickness h2 of the metal layer satisfies: 0.2μm ≤ h2 ≤ 10μm. This avoids stress damage to the metal layer caused by the insulating film due to an excessively thin metal layer, thus ensuring the coupling effect between the metal layer and the electrical connection surface. Furthermore, it avoids an excessively thick metal layer, thereby facilitating the design of thin conductive connectors.

[0014] In one possible implementation of this application, at the operating height of the conductive connector, the equivalent capacitance C1 per unit area of ​​the conductive connector satisfies: C1 ≥ 1 pF / mm 2 This allows for a larger coupling capacitance between the conductive connector and the electrical connection surface within the actual application area, thus meeting the requirements for coupled electrical connection.

[0015] In this application, the working height h3 of the conductive connector satisfies: 0.1mm ≤ h3 ≤ 0.5mm. This facilitates the thinner design of the conductive connector, which expands the range of applicable scenarios for the conductive connector.

[0016] Furthermore, at the aforementioned working height, the stress P of the conductive connector along the working height direction satisfies: P < 30 kPa. Therefore, the pressure exerted by the conductive connector on the electrical connection surface is relatively low, thus preventing damage to sensitive components.

[0017] This application does not limit the specific material of the insulating film, as long as it can effectively provide insulation and dielectric isolation. For example, the insulating film may include a metal oxide layer and a ceramic oxide layer, with the ceramic oxide layer covering the side of the metal oxide layer facing away from the metal layer; in this case, the insulating film may be a high-dielectric film. Alternatively, the insulating film may be made of at least one of polyimide, polyethylene terephthalate, polytetrafluoroethylene, or polyvinylidene fluoride; in this case, the insulating film may be an organic polymer film.

[0018] Secondly, this application also provides a mobile terminal, which includes a display screen, a floor, and a conductive connector as described in the first aspect. The display screen includes a ground layer, and the ground layer and the floor are electrically coupled through the conductive connector. In the mobile terminal provided by this application, the ground layer of the display screen and the floor are electrically coupled through the conductive connector. Since the insulating film is located on the outermost side of the conductive connector, serving as the outer surface of the conductive connector in contact with the ground layer and the floor, and the relative permittivity of the insulating film is greater than 1, a large coupling capacitance can be generated between the ground layer and the floor to achieve the electrical coupling between them. This helps to solve problems such as passive modulation and radiated stray emissions. Furthermore, even with a small thickness, the electrical coupling requirements between the ground layer and the floor can be met. Additionally, using the conductive connector design provided in this application, as long as the conductive connector can be clamped between the ground layer and the floor, the requirements for contact reliability between the conductive connector and the display screen and the floor are low, thus reducing the pressure requirements between the conductive connector and the display screen and the floor, effectively reducing the risk of screen printing defects. Therefore, the mobile terminal design scheme provided in this application can meet the communication and display requirements of the mobile terminal while facilitating the miniaturization of the mobile terminal.

[0019] Thirdly, this application also provides a method for preparing a conductive connector, the method comprising:

[0020] A metal layer is formed on the outside of the foam;

[0021] An insulating film is formed on the surface of the metal layer, wherein the relative permittivity of the insulating film is greater than 1.

[0022] The conductive connector prepared by the method provided in this application can effectively avoid direct contact between the metal layer and the electrical connection surface when the conductive connector is applied between two electrical connection surfaces because the insulating film covers the metal layer. Instead, a coupling capacitance is generated between the metal layer and the electrical connection surface, thereby realizing the coupling electrical connection between the electrical connection surfaces, which is beneficial to improving the reliability of the electrical connection between the electrical connection surfaces.

[0023] In one possible implementation of this application, forming a metal layer on the outside of the foam may include forming an aluminum-silicon alloy thin film on the outside of the foam by aluminum-silicon co-sputtering. This is beneficial for improving the bending reliability of the metal layer and allows for finer grains on the surface of the metal layer, which is beneficial for improving the structural reliability of the metal layer, thereby improving the product yield of the conductive connector.

[0024] Furthermore, in the aforementioned aluminum-silicon alloy thin film, the mass doping ratio of silicon is less than 25%. This improves the fluidity of the aluminum-silicon alloy during sputtering, thereby increasing the yield strength. This is beneficial for reducing the bending radius of the aluminum-silicon alloy thin film, thus improving the reliability of the bending structure of the aluminum-silicon alloy thin film.

[0025] In one possible implementation of this application, an insulating film is formed on the surface of the metal layer, including:

[0026] Oxygen is introduced and metallic aluminum is sputtered to form an aluminum oxide layer on the surface of an aluminum-silicon alloy thin film;

[0027] A ceramic oxide layer is formed by sputtering on the surface of alumina.

[0028] The insulating film formed in this way is a composite film layer consisting of an alumina layer and a ceramic oxide layer. The ceramic oxide layer can serve as an outer protective film for the alumina, which helps to improve the overall wear resistance of the insulating layer.

[0029] In another possible implementation of this application, an insulating film is formed on the surface of the metal layer, including:

[0030] An organic polymer solution is coated onto the surface of the metal layer;

[0031] The organic polymer material solution is cured at high temperature to form an insulating film.

[0032] The insulating film formed in this way is an organic polymer material layer. The process of preparing the insulating film using this method is relatively easy to control, which is conducive to improving the product yield of conductive connectors.

[0033] In this application, the absolute viscosity of the above-mentioned organic polymer material solution can be greater than or equal to 2000 mPa·s to ensure the structural reliability of the insulating film obtained by high-temperature curing.

[0034] In addition, high-temperature curing of the organic polymer solution includes placing the organic polymer solution in an environment at a temperature of 160°C to 180°C for t hours, where t satisfies: 0.1 ≤ t ≤ 1. This ensures that the structure of the cured insulating film is more reliable.

[0035] In this application, forming an insulating film on the surface of a metal layer includes such that the minimum distance d1 between the edge of the projection of the metal layer and the edge of the projection of the insulating film satisfies the following condition with respect to the dimension D1 of the projection of the insulating film in a first direction: 1%×D1≤D1-d1≤10%×D1, where the first direction is the direction in which the minimum distance d1 is located.

[0036] This helps to increase the coverage of the insulating film over the metal layer, thereby reducing the risk of metal layer exposure.

[0037] In another possible implementation of this application, the above method may further include:

[0038] A substrate layer is formed on the outside of the foam, and the substrate layer is an insulating material layer;

[0039] A metal layer is formed on the surface of the substrate layer.

[0040] This helps improve the structural reliability of conductive connectors. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the structure of a mobile terminal in an embodiment of this application;

[0042] Figure 2a A schematic diagram illustrating one implementation of a conductive connection between the grounding layer of the display screen and the ground in a mobile terminal provided in this application embodiment;

[0043] Figure 2b A schematic diagram of the surface structure of the display screen facing the floor;

[0044] Figure 3 A simplified structural diagram of a display screen whose grounding layer is electrically connected to the floor via conductive foam, as provided in an embodiment of this application.

[0045] Figure 4 This is a schematic diagram of a conductive connector provided in an embodiment of this application;

[0046] Figure 5 for Figure 4 A three-dimensional structural schematic diagram of the conductive connector shown;

[0047] Figure 6 A simplified structural diagram illustrating the electrical connection between a display screen and a floor via a conductive connector, as provided in an embodiment of this application.

[0048] Figure 7 A cross-sectional view of one structure of the membrane structure provided in the embodiments of this application;

[0049] Figure 8 A cross-sectional view of one structure of the membrane structure provided in the embodiments of this application;

[0050] Figures 9a to 9g This is a schematic diagram illustrating the manufacturing process of a conductive connector provided in an embodiment of this application;

[0051] Figures 10a to 10b This is a schematic diagram of another manufacturing process for the conductive connector provided in the embodiments of this application.

[0052] Figure label:

[0053] 100 - Cover plate; 200 - Display / module; 201 - Grounding layer; 300 - PCB; 400 - Mid-frame; 500 - Back cover; 600 - Bezel; 700 - Floor;

[0054] 800-radiator;

[0055] 10-Conductive foam; 1-Foam; 2-Metal layer; 21-Aluminum-silicon alloy film; 22-Aluminum metal layer; 20-Film structure; 3-Insulating film;

[0056] 31-Alumina layer; 32-Strontium barium titanate layer; 4-Substrate layer; 30-Mask plate; 301-Clearing area; 40-Organic polymer material solution. Detailed Implementation

[0057] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings. However, the exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein. The same reference numerals in the figures denote the same or similar structures, and therefore repeated descriptions of them will be omitted. The terms expressing position and direction described in the embodiments of this application are illustrative based on the accompanying drawings, but changes can be made as needed, and all such changes are included within the scope of protection of this application. The accompanying drawings of the embodiments of this application are only for illustrating relative positional relationships and do not represent actual scale.

[0058] It should be noted that specific details are set forth in the following description to facilitate understanding of this application. However, the embodiments of this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the embodiments of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0059] The following explains the terminology that may appear in the embodiments of this application.

[0060] Radiator: In an antenna, this is the device used to receive / transmit electromagnetic wave radiation. In some cases, the term "antenna" is narrowly defined as a radiator, which converts guided wave energy from the transmitter into radio waves, or converts radio waves into guided wave energy, for radiating and receiving radio waves. The modulated high-frequency current energy (or guided wave energy) generated by the transmitter is transmitted to the transmitting radiator via a feed line, where it is converted into electromagnetic wave energy of a specific polarization and radiated in the desired direction. The receiving radiator converts the electromagnetic wave energy of a specific polarization from a specific direction in space back into modulated high-frequency current energy, which is then transmitted to the receiver input via a feed line.

[0061] Ground / Plug: This can broadly refer to at least a portion of any grounding layer, ground plane, or grounding metal layer within a mobile terminal (such as a mobile phone), or at least a portion of any combination of the aforementioned grounding layers, ground planes, or grounding components. "Ground / Plug" can be used for grounding components within the mobile terminal. In one embodiment, "Ground / Plug" may include any one or more of the following: a grounding layer of the mobile terminal's circuit board, a ground plane formed by the mobile terminal's frame, a grounding metal layer formed by a metal film beneath the display screen, a conductive grounding layer of the battery, and conductive or metallic components electrically connected to the aforementioned grounding layer, ground plane, or metal layer. In one embodiment, the circuit board may be a printed circuit board (PCB), such as an 8-layer, 10-layer, or 12-14-layer board with 8, 10, 12, 13, or 14 layers of conductive material, or components separated and electrically insulated by dielectric or insulating layers such as glass fiber or polymers.

[0062] Any of the aforementioned grounding layers, ground planes, or grounding metal layers are made of conductive materials. In one embodiment, the conductive material may be any of the following: copper, aluminum, stainless steel, brass and their alloys, copper foil on an insulating substrate, aluminum foil on an insulating substrate, gold foil on an insulating substrate, silver-plated copper, silver-plated copper foil on an insulating substrate, silver foil on an insulating substrate and tin-plated copper, cloth impregnated with graphite powder, graphite-coated substrates, copper-plated substrates, brass-plated substrates, and aluminum-plated substrates. Those skilled in the art will understand that grounding layers, ground planes, or grounding metal layers may also be made of other conductive materials.

[0063] Capacitance: can be understood as lumped capacitance and / or distributed capacitance. Lumped capacitance includes capacitive components, such as capacitor elements; distributed capacitance (or distributed capacitance) includes the equivalent capacitance formed by two conductive components separated by a certain gap.

[0064] Coupling: In this application, it can be understood as indirect coupling, and "coupled connection" can be understood as indirect coupling connection. "Indirect coupling" can be understood as two conductors conducting electricity through a gap / non-contact manner. In one embodiment, indirect coupling can also be called capacitive coupling, for example, signal transmission is achieved by forming an equivalent capacitance through coupling between the gaps between two conductive parts.

[0065] To facilitate understanding of the mobile terminal provided in the embodiments of this application, its application scenarios will be introduced first below.

[0066] Figure 1 An exemplary embodiment of a mobile terminal provided in this application is illustrated, with a mobile phone as the example. Figure 1As shown, in one embodiment, the mobile terminal includes a cover 100, a display / module 200, a printed circuit board (PCB) 300, a middle frame 400, and a rear cover 500. It should be understood that in some embodiments, the cover 100 may be a glass cover, or it may be replaced with a cover made of other materials, such as an ultra-thin glass cover, a polyethylene terephthalate (PET) cover, etc. In one embodiment, the cover 100, display 200, middle frame 400, and rear cover 500 can all be considered as part of the housing.

[0067] The cover plate 100 can be set close to the display screen 200, and can be mainly used to protect the display screen 200 from dust.

[0068] In one embodiment, the display screen 200 may include a liquid crystal display (LCD), a light emitting diode (LED) display panel, or an organic light-emitting diode (OLED) display panel, etc., and this application does not limit it.

[0069] The 400mm mid-frame primarily serves to support the entire machine. Figure 1 The diagram shows PCB 300 positioned between the middle frame 400 and the rear shell 500. It should be understood that in one embodiment, PCB 300 may also be positioned between the middle frame 400 and the display screen 200; this application does not impose any limitations on this. PCB 300 may be made of flame-retardant material (FR-4) dielectric substrate, Rogers dielectric substrate, or a hybrid dielectric substrate of Rogers and FR-4, etc. Here, FR-4 is a designation for a flame-retardant material grade, and Rogers dielectric substrate is a high-frequency board. Electronic components, such as radio frequency chips, are mounted on PCB 300.

[0070] In one embodiment, a metal layer may be disposed on the PCB 300. This metal layer can be used to ground electronic components carried on the PCB 300, or to ground other components such as bracket antennas, frame antennas, etc. This metal layer may be referred to as a ground plane, grounding plate, or grounding layer. In one embodiment, this metal layer can be formed by etching metal onto the surface of any layer of the dielectric substrate in the PCB 300. In one embodiment, the grounding metal layer may be disposed on the side of the PCB 300 near the middle frame 400. In one embodiment, the edge of the printed circuit board PCB 300 can be considered as the edge of its grounding layer. In one embodiment, the metal middle frame 400 can also be used for grounding the aforementioned components. The mobile terminal may also have other ground planes / grounding plates, as previously described, which will not be repeated here.

[0071] The mobile terminal may also include a battery (not shown in the figure). The battery may be disposed between the middle frame 400 and the rear cover 500, or between the middle frame 400 and the display screen 200, and this application does not limit this. In some embodiments, the PCB 300 is divided into a motherboard and a daughterboard, and the battery may be disposed between the motherboard and the daughterboard. The motherboard may be disposed between the middle frame 400 and the upper edge of the battery, and the daughterboard may be disposed between the middle frame 400 and the lower edge of the battery.

[0072] The mobile terminal may also include a frame 600, which may be formed of a conductive material such as metal. The frame 600 may be disposed between the display screen 200 and the back cover 500 and extend circumferentially around the periphery of the mobile terminal. The frame 600 may have four sides surrounding the display screen 200 to help secure the display screen 200. In one implementation, the frame 600 made of metal can be directly used as the metal frame of the mobile terminal, forming a metal frame appearance suitable for industrial design (ID). In another implementation, the outer surface of the frame 600 may also be made of a non-metallic material, such as a plastic frame, forming a non-metallic frame appearance suitable for non-metallic ID.

[0073] The mid-frame 400 may include a border 600. The mid-frame 400, including the border 600, is a single unit that supports the electronic components within the device. The cover plate 100 and the rear shell 500 respectively cover the upper and lower edges of the border 600 to form the outer shell or housing of the mobile terminal. Alternatively, the border 600 may not be considered part of the mid-frame 400. In one embodiment, the border 600 may be connected to the mid-frame 400 and integrally formed. In another embodiment, the border 600 may include inwardly extending protrusions to connect with the mid-frame 400, for example, via spring clips, screws, welding, etc. In one embodiment, the cover plate 100, rear shell 500, border 600, and mid-frame 400 may be collectively referred to as the outer shell or housing of the mobile terminal. It should be understood that "outer shell or housing" can be used to refer to part or all of any one of the cover plate 100, rear shell 500, side frame 600 or middle frame 400, or to part or all of any combination of the cover plate 100, rear shell 500, side frame 600 or middle frame 400.

[0074] The back cover 500 can be made of metal; it can also be made of non-conductive material, such as glass or plastic; or it can be made of both conductive and non-conductive materials.

[0075] In one embodiment, the frame 600 can at least partially function as a radiator to receive / transmit radio frequency signals. This portion of the frame acting as the radiator may have gaps between itself and other parts of the middle frame 400, or between itself and the middle frame 400, thereby ensuring a good radiation environment for the radiator. In one embodiment, an aperture may be provided near this portion of the frame acting as the radiator. In one embodiment, the aperture may include an aperture disposed inside the mobile terminal, for example, an aperture not visible from the exterior of the mobile terminal. In one embodiment, the internal aperture may be formed by any one or multiple of the middle frame 400, battery, PCB 300, back cover 500, display screen 200, and other internal conductive components; for example, the internal aperture may be formed by a structural component of the middle frame 400. In one embodiment, the aperture may also include a gap / slit / opening on the frame 600. In one embodiment, the gap / slit / opening on the frame 600 may be a slit formed on the frame 600, at which the frame 600 is divided into two parts without a direct connection. In one embodiment, the aperture may further include a slit / gap / aperture provided on the back cover 500 or the display screen 200. In one embodiment, the back cover 500 includes a conductive material, and the aperture provided in the conductive material may communicate with a slit or gap in the frame to form a continuous aperture on the surface of the mobile terminal.

[0076] In one embodiment, the radiator of the mobile terminal may also be disposed within the frame 600. The frame 600 comprises a non-conductive material, and the radiator of the antenna may be located within the mobile terminal and disposed along the frame 600, or the radiator may be at least partially embedded within the non-conductive material of the frame. In one embodiment, the radiator is disposed close to the non-conductive material of the frame 600 to minimize the volume occupied by the radiator and to be closer to the outside of the mobile terminal, thereby achieving better signal transmission performance. It should be noted that "disposed close to the frame 600" means that the radiator can be disposed tightly against the frame 600 or close to the frame 600, for example, there may be a small gap between the radiator and the frame 600.

[0077] In one embodiment, the radiator of the mobile terminal may also be disposed within the housing, such as a bracket antenna. A gap may exist between the radiator disposed within the housing and other conductive components inside the housing, thereby ensuring a good radiation environment for the radiator. In one embodiment, an aperture may be disposed near the radiator. In one embodiment, the aperture may include an aperture disposed inside the mobile terminal, for example, an aperture not visible from the exterior of the mobile terminal. In one embodiment, the internal aperture may be formed by any one or multiple of the frame 600, mid-frame 400, battery, PCB 300, back cover 500, display screen 200, and other internal conductive components; for example, the internal aperture may be formed by a structural component of the mid-frame 400. In one embodiment, the aperture may also include a slot / slit / opening on the frame 600. In one embodiment, the slot / slit / opening on the frame 600 may be a slit formed on the frame, dividing the frame 600 into two parts without direct connection at the slit. In one embodiment, the aperture may also include a slot / slit / opening on the back cover 500 or the display screen 200. In one embodiment, the back cover 500 includes a conductive material, and the apertures formed in the conductive material can communicate with the slots or gaps in the frame to form continuous apertures on the surface of the mobile terminal. In one embodiment, the apertures on the back cover 500 or the display screen can also be used to house other devices, such as cameras, and / or sensors, and / or microphones, and / or speakers, etc.

[0078] In one embodiment, the antenna can be based on a flexible printed circuit (FPC), a laser-direct-structuring (LDS) antenna, or a microstrip disk antenna (MDA), among other forms. In another embodiment, the antenna can be a transparent or semi-transparent structure embedded within the screen of the mobile terminal, making it a transparent antenna element embedded within the screen of the mobile terminal.

[0079] Figure 1 The images only schematically illustrate some of the components included in the mobile terminal; the actual shape, size, and construction of these components are not subject to change. Figure 1 limited.

[0080] In this application, the mobile terminal may include, but is not limited to, mobile phones, tablets, laptops, e-book readers, cameras, wearable devices, or home electronic devices. For ease of understanding, mobile phones are used as examples in the various embodiments of this application.

[0081] As explained above, antennas are crucial for enabling the communication functions of mobile terminals. In practical applications, to meet communication requirements, some antennas require grounding, meaning the radiating element of the antenna is electrically connected to the ground to conduct the current from the radiating element to the ground. Typically, this conductive connection between the radiating element and the ground is achieved through the conductive connection between the display screen and the ground. For example... Figure 2a As shown, Figure 2a This is a schematic diagram illustrating one implementation of a conductive connection between the grounding layer of the display screen and the ground plane in a mobile terminal provided in this application embodiment. For ease of illustration, this... Figure 2a The display screen is omitted.

[0082] Additionally, refer to Figure 2b , Figure 2b The diagram shows the surface structure of the display screen facing the floor. As can be seen from the above description, the surface of the display screen facing the floor 700 has a grounding layer 201. The grounding layer 201 can be a thin metal film. Therefore, the conductive connection between the display screen 200 and the floor 700 is actually the conductive connection between the grounding layer 201 and the floor 700.

[0083] like Figure 2a As shown, the radiator 800 of the antenna is disposed on the frame of the mobile terminal. The radiator 800 is disposed close to the ground layer 201 of the display screen 200, so that the radiator 800 can achieve conductive connection with the ground floor 700 through coupling with the ground layer 201.

[0084] Figure 2a This is merely an illustrative example of the placement of the antenna radiator 800; that is, the radiator 800 can be placed not only on the moving frame but also in other locations. However, it can be electrically connected to the ground plane 700 through the grounding layer 201 of the display screen 200.

[0085] As can be seen from the above introduction, in mobile terminals, the Floor 700 can, but is not limited to, [functions]. Figure 1 The PCB300, the middle frame 400, or the back cover 500 shown are one or more combinations thereof.

[0086] You can continue to refer to Figure 2a and Figure 2b In this embodiment, the ground layer 201 of the display screen 200 is electrically connected to the floor 700 via conductive foam 10. It is worth mentioning that... Figure 2a The text only shows some possible locations of the conductive foam 10 used to electrically connect the grounding layer 201 of the display screen 200 to the floor 700 in the mobile terminal. In practical applications, it can be set not only near the top area of ​​the mobile terminal, but also in other areas, such as near the bottom area.

[0087] Reference Figure 3 , Figure 3 This is a simplified structural diagram of a display screen and a floor electrically connected via conductive foam, as provided in an embodiment of this application. The conductive foam 10 includes foam 1 and a metal layer 2 wrapped around the surface of foam 1. When the conductive foam 10 is placed between the display screen 200 and the floor 700, the elastic force accumulated by the compressed foam 1 can be used to achieve a reliable connection between the metal layer 2 and the ground layer 201 of the display screen 200 and the floor 700.

[0088] Additionally, since the display screen 200 is typically fixedly connected to the frame around its perimeter, then... Figure 2a In the illustrated scheme, the conductive foam 10 is positioned close to the frame 600 to provide a stable clamping force to the conductive foam 10 by utilizing the connection between the display screen 100 and the frame.

[0089] It is understandable that the above Figure 3 The conductive connection between the grounding layer 201 of the display screen 200 and the floor 700 requires high pressure; excessive pressure poses a risk of screen erosion. For example... Figure 2a and Figure 2b As shown, since the radiator 800 of the antenna is positioned close to the grounding layer 201 of the display screen 200, so that the radiator 800 can achieve conductive connection with the grounding layer 700 through coupling with the grounding layer 201, if the pressure between the grounding layer 201 and the grounding layer 700 is insufficient, problems such as passive intermodulation (PIM), self-interference, and radiated spurious emission (RSE) are likely to occur, thereby affecting the communication performance of the mobile terminal's antenna.

[0090] In view of this, this application provides a conductive connector that requires minimal pressure while meeting electrical connection requirements, thereby reducing the risk of display screen printing defects and mitigating the impact of passive modulation and radiated spurious emissions on the communication performance of mobile terminals. To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0091] Reference Figure 4 , Figure 4 This is a schematic diagram of a conductive connector provided in an embodiment of this application. The conductive connector includes a foam 1 and a membrane structure 20, wherein the membrane structure 20 wraps around the periphery of the foam 1. It can be understood that, since the foam 1 has a certain degree of compressibility, when the membrane structure 20 wraps the foam 1, the foam 1 can be compressed to a certain extent, thereby making the foam 1 and the membrane structure 20 fit tightly together.

[0092] You can continue to refer to Figure 4 The membrane structure includes a metal layer 2 and an insulating film 3, with the insulating film 3 located on the side of the metal layer 2 facing away from the foam 1.

[0093] Additionally, refer to Figure 5 , Figure 5 for Figure 4 The diagram shows a three-dimensional structural schematic of the conductive connector. In this application, the insulating film 3 covers at least the surface of the metal layer 2 that is away from the foam 1. That is, the insulating film 3 is located on the outermost side of the entire conductive connector, serving as the outer surface of the conductive connector for contact with other structures.

[0094] In this application, the relative permittivity of the insulating film 3 may be greater than 1. For example, in one possible embodiment, the relative permittivity ε of the insulating film 3 satisfies: ε≥1.5, and can be 1.8, 1.9 or 3, etc., for example.

[0095] In practical applications, the relative permittivity of the insulating film 3 can be selected according to the antenna's operating frequency band. For example, when the antenna's operating frequency band is any band from 700MHz to 5GHz, the relative permittivity ε of the insulating film 3 can satisfy: 1.5≤ε≤3. This ensures that the coupling capacitance of the conductive connector can meet the antenna's grounding requirements.

[0096] When this conductive connector is applied between any two electrical connection surfaces, such as Figure 6 As shown, for example, when applied to the electrical connection between the ground layer of the display screen 200 and the ground floor 700, the insulating film 3 contacts the ground layer of the display screen 200 and the ground floor 700. Since the relative permittivity of the insulating film 3 is relatively large, it can generate a large coupling capacitance between the metal layer 2 and the ground layer of the display screen 200 and the ground floor 700. This satisfies the requirements for the coupling electrical connection between the ground layer of the display screen 200 and the ground floor 700, while also helping to solve the passive modulation problem, thereby improving the communication performance of the mobile terminal.

[0097] Furthermore, due to the design scheme of the conductive connector provided in this application, it is only necessary to ensure that the conductive connector can be clamped between the ground layer of the display screen 200 and the ground plane 700. This reduces the requirements for the contact reliability between the conductive connector and the display screen 200 and the ground plane 700, thus lowering the pressure requirements between them and reducing the risk of screen printing defects. Moreover, this scheme has lower requirements for the placement of the conductive connector; it can be placed near the bezel or in other locations, making its placement more flexible and facilitating the expansion of its application scenarios.

[0098] As explained above, to ensure effective coupling between conductive connectors and electrical connection surfaces, contact between the metal layer and the electrical connection surface should be avoided. Therefore, referring to... Figure 7 , Figure 7 This is a cross-sectional view of one possible film structure provided in an embodiment of this application. In this embodiment, along the stacking direction from the metal layer 2 to the insulating film 3, that is... Figure 7 In the third direction, the projection of the metal layer 2 falls within the outline of the projection of the insulating film 3. This effectively prevents the edges of the metal layer 2 from being exposed outside the insulating film 3. Therefore, when this conductive connector is applied between two electrical connection surfaces, the risk of direct contact between the metal layer 2 and the electrical connection surface can be effectively reduced, thereby ensuring the reliability of the coupling electrical connection between the two electrical connection surfaces.

[0099] In addition, continue to refer to Figure 7 The minimum distance d1 between the edge of the projection of the metal layer 2 and the edge of the projection of the insulating film 3 satisfies the following relationship with the dimension D1 of the insulating layer 3 in the first direction: 1% × D1 ≤ D1 - d1 ≤ 10% × D1, where the first direction is the direction in which the minimum distance d1 is located. Thus, in the aforementioned stacking direction, the projection of the metal layer 2 is contained within the outline edge of the projection of the insulating film 3, which ensures the insulation of the outer surface of the conductive connector.

[0100] In practical design, the arrangement of the membrane structure 20 can be adjusted according to specific application requirements. For example, it can be referred to... Figure 8 , Figure 8 This is a cross-sectional view of one embodiment of the membrane structure provided in this application. In this embodiment, the membrane structure 20 further includes a substrate layer 4, which is an insulating material layer, and a metal layer 2 is located between the substrate layer 4 and the insulating film 3. This allows the substrate layer 4 and the insulating film 3 to enclose the metal layer 2, which helps to improve the structural reliability of the conductive connector.

[0101] It is understood that in this embodiment of the application, the use of the substrate layer 4 and the insulating film 3 to jointly encapsulate the metal layer 2 is beneficial to simplifying the preparation process of the film structure 20, thereby improving the feasibility of preparing the film structure 20 and thus improving the product yield of the film structure 20.

[0102] In addition, such as Figure 8 As shown, along the stacking direction from metal layer 2 to substrate layer 4, which can also be represented by a third direction, the projection of metal layer 2 falls within the outline of the projection of substrate layer 4. In one possible embodiment, the minimum distance d2 between each edge of the projection of metal layer 2 and the edge of the projection of substrate layer 4 satisfies the following relationship with the dimension D2 of the projection of substrate layer 4 in a second direction: 1% × D2 ≤ D2 - d2 ≤ 10% × D2, where the second direction is the direction where the minimum distance d2 is located, and the second direction may be the same as or different from the first direction. This ensures that the projection of metal layer 2 is contained within the outline edge of the projection of substrate layer 4. This allows the insulating film 3 to cover the edge of metal layer 2, thereby completely enclosing metal layer 2 between the insulating film 3 and substrate layer 4, preventing metal layer 2 from being exposed. This helps reduce the risk of metal layer 2 contacting the electrical connection surface, thus effectively avoiding passive modulation problems.

[0103] It is worth mentioning that this application does not limit the first direction mentioned above, which can be any direction within the surface of the substrate layer 4, so that the size of the metal layer 2 in each direction within the surface of the substrate layer 4 is smaller than that of the substrate layer 4, thereby ensuring that the metal layer 2 can be completely wrapped between the insulating film 3 and the substrate layer 4.

[0104] In one possible embodiment of this application, the thickness h1 of the insulating film 3 satisfies: 0.2μm ≤ h1 ≤ 5μm, and can be 0.5μm, 1μm, 2μm, or 3.5μm, etc. This avoids the risk of metal layer 2 being exposed due to insufficient thickness of the insulating film 3; and also avoids the coupling effect between metal layer 2 and electrical connection surface being affected by excessive thickness of the insulating film 3. Therefore, selecting the thickness of the insulating film 3 within the above range can reduce the risk of passive modulation while forming a larger coupling capacitance.

[0105] Furthermore, as described above, when using the conductive connector provided in this application to achieve electrical connection between two electrical connection surfaces, the requirements for contact reliability between the conductive connector and the electrical connection surface are relatively low. Therefore, in order to reduce the influence of air on the dielectric constant between the metal layer 2 and the electrical connection surface, in one possible embodiment of this application, the surface roughness of the insulating film 3 can be less than 1 μm, for example, 0.8 μm, 0.7 μm, or 0.5 μm. This improves the adhesion tightness between the insulating film 3 and the electrical connection surface, thereby ensuring the effectiveness of adjusting the dielectric constant between the metal layer 2 and the electrical connection surface using the insulating film 3. This is beneficial for improving the consistency of the coupling capacitance in mass-produced conductive connectors, and consequently, for improving the consistency of the communication performance of mobile terminals using this conductive connector.

[0106] In this application, surface roughness refers to the difference between the minute peaks and valleys of a machined surface. It can be measured using a roughness measuring instrument.

[0107] It is worth mentioning that, using the conductive connector design scheme provided in the above embodiments of this application, in one possible embodiment, at the working height of the conductive connector, the equivalent coupling capacitance C1 per unit area of ​​the conductive connector can satisfy: C1≥1pF / mm 2 For example, C1 ≥ 2pF / mm 2 This allows for a larger coupling capacitance between the conductive connector and the electrical connection surface within the actual application area, thus meeting the requirements for coupled electrical connection.

[0108] In practical applications, the working height h3 of the conductive connector provided in this application can satisfy: 0.1mm ≤ h3 ≤ 0.5mm. For example, 0.2mm ≤ h3 ≤ 0.3mm. This facilitates the thin design of the conductive connector, which helps to expand the range of applicable scenarios for the conductive connector.

[0109] As can be seen from the above introduction, the design scheme of the conductive connector provided in this application can achieve a large equivalent coupling capacitance C of the conductive connector even with a small board area. For example, when the board area occupied by the conductive connector on the electrical connection surface is 2mm×8mm, the equivalent coupling capacitance C of the conductive connector is >30pF, which can meet the requirements of stable coupling electrical connection between the two electrical connection surfaces, thereby meeting the grounding requirements of the antenna.

[0110] Furthermore, this application does not limit the type of antenna, such as a cellular antenna, a global positioning system (GPS) antenna, or a Wi-Fi antenna, etc., and its operating frequency band can be, for example, the 0 to sub6 GHz band, such as the LB band, the MHB band, or the sub6 GHz band.

[0111] You can continue to refer to Figure 8 In this embodiment, the thickness h2 of the metal layer 2 can satisfy: 0.2μm ≤ h2 ≤ 10μm, and can be 0.5μm, 1μm, 2μm, 3.5μm, 5μm, 7μm, or 8.5μm, etc. This is because if the metal layer 2 is too thin, for example less than 0.2μm, it is easy to cause stress damage to the insulating film 3 to which the metal layer 2 is attached, which affects the coupling effect between the metal layer 2 and the electrical connection surface. In addition, if the thickness of the metal layer 2 is large, for example greater than 10μm, it will make the overall thickness of the conductive connector large, thus failing to meet the requirements of thin design. Therefore, selecting the thickness of the metal layer 2 within the above range can ensure the coupling effect between the metal layer 2 and the electrical connection surface while also achieving a thin design of the conductive connector, thereby helping to meet the thin design requirements of mobile terminals.

[0112] It is understandable that the choice of materials is also a key factor affecting structural reliability and dielectric constant. In one possible embodiment of this application, the substrate layer 4 may be a polymer material layer, the material of which may include, but is not limited to, at least one of polyimide (PI), polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), or polyvinylidene fluoride (PVDF), in order to improve the rigidity of the entire film structure 20, thereby contributing to the improvement of the reliability of the film structure 20.

[0113] In addition, in this application, the insulating film 3 may also be a polymer material layer, and its material may include, but is not limited to, at least one of PI, PET, PTFE, or PVDF. The insulating film 3 and the substrate layer 4 may be made of the same or different materials; this application does not limit their materials.

[0114] In some other possible embodiments of this application, the insulating film 3 may also be a composite film layer comprising a metal oxide layer and a ceramic oxide layer. The metal oxide layer may be, but is not limited to, an alumina layer. In other embodiments of this application, the metal oxide may also be replaced with silicon dioxide, etc.

[0115] The ceramic oxide layer may include, but is not limited to, at least one of barium strontium titanate, barium titanate, or strontium titanate. Due to the high hardness of the ceramic oxide layer, in this embodiment, the ceramic oxide layer can cover the surface of the metal oxide layer facing away from the metal layer 2, so that the ceramic oxide layer acts as a protective layer for the metal oxide layer, thereby improving the wear resistance of the insulating film 3.

[0116] It is worth mentioning that, since the material properties of ceramic oxides are similar to those of metal oxides, they can ensure the adhesion of ceramic oxides to the surface of the metal oxide layer, thereby improving the structural reliability of the insulating film 3, which is beneficial to improving the stability of the dielectric constant of the insulating film 3.

[0117] After understanding the structure of the conductive connector provided in this application, the following will provide an exemplary description of the preparation method of the conductive connector and the performance of the prepared conductive connector in conjunction with specific embodiments.

[0118] This application also provides a method for preparing a conductive connector to obtain the above-mentioned... Figures 4 to 8 The conductive connector shown in the figure, the method includes the following steps:

[0119] Step 1: Form a metal layer 2 on the outside of foam 1; form an insulating film 3 on the surface of the metal layer 2, wherein the relative permittivity of the insulating film 3 is greater than 1.

[0120] In one embodiment, forming a metal layer 2 on the outside of foam 1 includes forming an aluminum-silicon alloy film on the outside of foam 1 by aluminum-silicon co-sputtering.

[0121] In one embodiment, the mass doping ratio of silicon in the aluminum-silicon alloy thin film is less than 25%.

[0122] In one embodiment, an insulating film 3 is formed on the surface of the metal layer 2, specifically by introducing oxygen and sputtering metallic aluminum to form an aluminum oxide layer on the surface of the aluminum-silicon alloy film; and a ceramic oxide layer is sputtered on the aluminum oxide surface.

[0123] In one embodiment, an insulating film 3 is formed on the surface of the metal layer 2, specifically by coating the surface of the metal layer 2 with an organic polymer solution; and curing the organic polymer solution at high temperature to form the insulating film 3.

[0124] In one embodiment, the absolute viscosity of the above-mentioned organic polymer material solution is greater than or equal to 2000 mPa·s.

[0125] In one embodiment, the above-mentioned high-temperature curing of the organic polymer solution includes placing the organic polymer solution in an environment with a temperature of 160°C to 180°C for t hours, wherein t satisfies: 0.1 ≤ t ≤ 1.

[0126] In one embodiment, the method of forming an insulating film 3 on the surface of the metal layer 2 ensures that the minimum distance d1 between the edge of the projection of the metal layer 2 and the edge of the projection of the insulating film 3 satisfies the following condition with respect to the dimension D1 of the projection of the insulating film 3 in a first direction: 1% × D1 ≤ D1 - d1 ≤ 10% × D1, where the first direction is the direction in which the minimum distance d1 is located. This ensures the coverage of the metal layer 2 by the insulating film 3, thereby reducing the risk of the metal layer 2 being exposed.

[0127] The above preparation method may further include the following steps:

[0128] Step 2: A substrate layer is formed on the outside of foam 1. The substrate layer is an insulating material layer. The aforementioned metal layer 2 is formed on the surface of the substrate layer.

[0129] In one embodiment, forming the metal layer 2 on the surface of the substrate layer can make the projection of the metal layer 2 fall within the outline of the projection of the substrate layer in the stacking direction from the metal layer 2 to the substrate layer; and the insulating film 3 covers the edge of the metal layer 2.

[0130] In one embodiment, forming the metal layer 2 on the surface of the substrate layer can satisfy the following condition with respect to the minimum distance d2 between the edge of the projection of the metal layer 2 and the edge of the projection of the substrate layer, and the dimension D2 of the projection of the substrate layer in the second direction: 1%×D2≤D2-d2≤10%×D2, where the second direction is the direction in which the minimum distance d2 is located.

[0131] In one possible embodiment, the insulating film 3 of the conductive connector can be formed by magnetron sputtering. Specifically, this application also provides a method for preparing a conductive connector, which includes the following steps:

[0132] Step 1: Form a metal layer 2 on the surface of the substrate layer 4. In one embodiment, a mask 30 may be placed on the surface of the substrate layer 4, as shown in the figure. Figure 9a , Figure 9a The relative positional relationship between the photomask 30 and the substrate layer 4 is shown. Then, by aluminum-silicon co-sputtering, an aluminum-silicon metal alloy thin film 21 is formed on the surface of the substrate layer 4 using the cutout area 301 of the photomask 30, thereby obtaining... Figure 9b The structure shown, Figure 9b A cross-sectional view used to show the structure of an aluminum-silicon metal alloy thin film 21 formed on the surface of the substrate layer 4.

[0133] Understandably, in order to ensure the conductivity of metal layer 2, such as Figure 9b As shown, in the actual process of forming the metal layer 2, a metal aluminum layer 22 of a certain thickness can be formed on the surface of the substrate layer 4 first, and then aluminum-silicon co-sputtering is performed to form an aluminum-silicon metal alloy thin film 21 on the surface of the metal aluminum layer 22.

[0134] It is worth mentioning that in step one above, the thickness of the aluminum-silicon metal alloy thin film 21 formed can be 1μm to 10μm, so as to ensure the coupling effect that the metal layer 2 can achieve while reducing the impact on the thickness of the formed conductive connector.

[0135] Furthermore, in the actual preparation process, the mass doping ratio of silicon in the aluminum-silicon alloy thin film 21 can be less than 25%, for example less than 15%, such as less than 10%, 5%, or 2%. This improves the flowability of the aluminum-silicon alloy on the surface of the substrate layer 4 during sputtering, thereby increasing the yield strength and allowing the bending radius of the aluminum-silicon alloy thin film 21 to be less than 0.1 mm, which is beneficial to improving the bending structure reliability of the aluminum-silicon alloy thin film 21. In addition, the aluminum-silicon alloy thin film 21 formed by this method has fewer surface defects, resulting in finer grains on the surface of the metal layer 2, which is beneficial to improving the structural reliability of the metal layer 2, thereby improving the product yield of the conductive connector.

[0136] Step 2: Form an insulating film 3 on the surface of the metal layer 2. In this step, oxygen can be introduced and metallic aluminum can be sputtered to form an aluminum oxide layer 31 on the surface of the aluminum-silicon alloy thin film 21, thereby obtaining the desired result. Figure 9c The structure shown, Figure 9c A cross-sectional view used to show the structure in which an aluminum oxide layer 31 is formed on the surface of metal layer 2.

[0137] Considering that the alumina layer 31 is relatively soft and not wear-resistant, a barium strontium titanate layer 32 can be sputtered onto the surface of the alumina layer 31 to obtain, for example, Figure 9d The structure shown, Figure 9d A cross-sectional view used to illustrate the structure after the composite insulating film is formed. Thus, a composite insulating film comprising an alumina layer 31 and a barium strontium titanate layer 32 is formed on the surface of the aluminum-silicon alloy thin film 21, so that the barium strontium titanate layer 32 serves as an outer protective film for the alumina 31, thereby improving the overall wear resistance of the insulating film.

[0138] It is worth mentioning that in step two above, the thickness of the formed alumina layer 31 can be 50nm to 100nm, for example, 65nm, 73nm, 85nm, or 90nm. Additionally, the thickness of the barium strontium titanate layer 32 can be 0.6μm to 1μm, for example, 0.7μm, 0.8μm, or 0.95μm. This allows the overall thickness of the formed composite insulating film to be within 0.2μm to 2μm.

[0139] In addition, since the alumina layer 31 has good adhesion to the aluminum-silicon alloy film 21, and the alumina layer 31 and the barium strontium titanate layer 32 have similar material properties, there is a large adhesion between the barium strontium titanate layer 32 and the alumina 31, thus ensuring the structural reliability of the obtained composite insulating film.

[0140] As can be understood from the above introduction, the above-mentioned composite insulating film can also be formed by other metal oxide layers and ceramic oxide layers. The specific preparation process and the performance of the resulting film are similar to those in the above embodiments, and will not be described in detail here.

[0141] It is understandable that in step one above, multiple metal layers 2 can be formed on the surface of the substrate layer 4 through a single masking process. Furthermore, during the formation of the alumina layer 31, an insulating film 3 can still be formed on the surfaces of the multiple metal layers 2 using a single masking process. This results in a multi-layered, interconnected structure, which improves the production efficiency of the film structure and consequently, the production efficiency of the conductive connector.

[0142] In addition, in the actual preparation process, the above-mentioned interconnected film layer structures can be cut by die-cutting process to obtain multiple independent film layer structures.

[0143] It is worth mentioning that, in the above-mentioned die-cutting process, cutting can be performed along the extension direction of the surface of the substrate layer 4, for example, in the length and / or width direction, at a position where the size of the insulating film 3 exceeds the size of the metal layer 2 by 1% to 10%. Alternatively, along the stacking direction from the metal layer 2 to the substrate layer 4, cutting can be performed at a position where the minimum distance d2 between the edge of the projection of the metal layer 2 and the edge of the projection of the substrate layer 4 satisfies the condition 1% × D2 ≤ D2 - d2 ≤ 10% × D2 between the projection of the substrate layer 4 in the second direction. Alternatively, along the stacking direction from the metal layer 2 to the insulating film 3, cutting can be performed at a position where the minimum distance d1 between the edge of the projection of the metal layer 2 and the edge of the projection of the insulating film 3 satisfies the condition 1% × D1 ≤ D1 - d1 ≤ 10% × D1 between the projection of the insulating film 3 in the first direction. This forms a shape as described above. Figure 9e The film structure 20 shown is beneficial for increasing the coverage of the insulating film 3 over the metal layer 2.

[0144] Step 3: Wrap the foam 1 with the film structure 20 obtained in Step 2 to obtain a conductive connector. In one embodiment, refer to... Figure 9f Foam 1 is placed on one side surface of membrane structure 20; then, both ends of membrane structure 20 are bent to the same side to wrap foam 1, thereby obtaining... Figure 9g The conductive connector shown.

[0145] As can be understood from the above description of the structure of the conductive connector provided in this application, in some possible embodiments of this application, the conductive connector may not have a substrate layer 4, and the metal layer 2 may be formed on other supporting film layers or structures. After the metal layer 2 and the insulating film 3 are formed, the other supporting film layers or structures can be removed to obtain the film structure 20.

[0146] Furthermore, the method for preparing the conductive connector provided in this application is not limited to the order of the above steps. For example, in one possible embodiment, a metal layer 2 may be formed on the outside of the foam 1, and then an insulating film 3 may be formed on the surface of the metal layer 2. In another possible embodiment, a substrate layer 4 may be formed on the outside of the foam 1, and then a metal layer 2 may be formed on the surface of the substrate layer 4, and an insulating film 3 may be formed on the surface of the metal layer 2.

[0147] To illustrate the performance of the conductive connectors prepared using the preparation method provided in the above embodiments of this application, Table 1 below shows the following specifications: Figure 9g The conductive connector shown Figure 3 The performance of the foams shown, ultra-soft foams (e.g., foams with a maximum compression ratio of over 80%), and metal springs in electrical connections between two electrical contact surfaces was compared.

[0148] Table 1

[0149]

[0150] The above comparison shows that, with the same board area, the conductive connector prepared using the above method generates a pressure P along the working height direction that satisfies the condition: P < 30 kPa. This results in lower pressure on the electrical connection surface, thus preventing damage to sensitive components such as the display screen. Furthermore, the unit area coupling capacitance C1 of this conductive connector is ≥ 2 pF / mm². 2 Within an area of ​​2mm × 8mm, its coupling capacitance C > 30pF, thus meeting the antenna grounding requirements and improving the communication performance of the mobile terminal. Furthermore, this conductive connector exhibits good wear resistance, which helps extend its service life.

[0151] Furthermore, the dielectric constant ε of the insulating film of the conductive connector prepared by the above method satisfies 1.5 ≤ ε ≤ 3. This effectively solves the passive modulation problem, thereby reducing self-interference and RSE risks, and improving the communication performance of mobile terminals.

[0152] In another possible embodiment of this application, the insulating film 3 can also be formed by coating. Unlike the above-described method of preparing conductive connectors by magnetron sputtering, in this embodiment, as... Figure 10a As shown, a mask 30 can be placed on a substrate layer 4 on which the metal layer 2 is formed, with the cutout area 301 of the mask 30 facing the metal layer 2 to expose the metal layer 2. Then, refer to... Figure 10bA solution of at least one aqueous or oily organic polymer material 40, such as PI, PET, PTFE or PVDF, is coated on the surface of a mask plate 30 and cured at high temperature for a set time to obtain a high dielectric coupling film 3.

[0153] In this embodiment, the method of forming the metal layer 2 is not limited; it can also be formed by coating, for example.

[0154] It is worth mentioning that, in one possible embodiment of this application, the absolute viscosity of the above-mentioned organic polymer material solution 40 can be greater than or equal to 2000 millipas per second (mPa·s), for example, 4000 mPa·s, in order to ensure the structural reliability of the insulating film 3 obtained by high-temperature curing.

[0155] Furthermore, the aforementioned high-temperature curing process can be carried out in a high-temperature curing oven. The high-temperature curing temperature can be, for example, 160℃~200℃, and the curing time can be t hours, where t can, for example, satisfy 0.1≤t≤1. For instance, the curing time can be half an hour. It is understood that the aforementioned high-temperature curing temperature and time can be specifically adjusted according to actual production needs to ensure that the structure of the cured insulating film 3 is more reliable.

[0156] Since the subsequent steps after the formation of insulating film 3 are similar to the preparation method provided in the above embodiments, they will not be described in detail here.

[0157] Comparative analysis shows that the conductive connectors with insulating film 3 formed by coating have similar performance to the conductive connectors prepared by magnetron sputtering. In other words, they both have advantages such as low pressure, large coupling capacitance, high wear resistance, and the ability to solve passive modulation problems.

[0158] It is understood that the method for preparing the conductive connector provided in this application is not limited to this. In other embodiments of this application, any possible method can be used to prepare the conductive connector. They will not be listed one by one here, but they should all be understood to fall within the protection scope of this application.

[0159] The above embodiments are merely exemplary descriptions of possible arrangements of the conductive connectors provided in this application. In the various embodiments of this application, unless otherwise specified or logically conflicting, the terms and / or descriptions between different embodiments are consistent and can be referenced to each other. The technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0160] Furthermore, in the above embodiments, the description is based on the example of the ground layer of the display screen and the ground plane being the two electrical connection surfaces that are electrically connected by the conductive connector. In other possible embodiments of this application, the conductive connector can also be used for coupling electrical connections between other electrical connection surfaces, and their specific applications are similar, so they will not be listed one by one here.

[0161] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An electrically conductive connector, characterized by It includes foam and a membrane structure, wherein the membrane structure wraps around the periphery of the foam, wherein: The membrane structure includes a metal layer and an insulating film, wherein the insulating film at least covers the surface of the metal layer opposite to the foam. The relative permittivity of the insulating film is greater than 1.

2. The electrically conductive connector of claim 1, wherein, Along the stacking direction from the metal layer to the insulating film, the projection of the metal layer falls within the outline of the projection of the insulating film.

3. The electrically conductive connector of claim 2, wherein, The minimum distance d1 between the edge of the projection of the metal layer and the edge of the projection of the insulating film satisfies the following relationship with the dimension D1 of the projection of the insulating film in the first direction: 1%×D1≤D1-d1≤10%×D1, where the first direction is the direction in which the minimum distance d1 is located.

4. An electrically conductive connector as claimed in any one of claims 1 to 3, wherein The film structure further includes a substrate layer, which is an insulating material layer; the metal layer is located between the substrate layer and the insulating film.

5. The conductive connector of claim 4, wherein, Along the stacking direction from the metal layer to the substrate layer, the projection of the metal layer falls within the outline of the projection of the substrate layer; the insulating film covers the edge of the metal layer.

6. The conductive connector of claim 5, wherein, The minimum distance d2 between the edge of the projection of the metal layer and the edge of the projection of the substrate layer satisfies the following relationship with the dimension D2 of the projection of the substrate layer in the second direction: 1%×D2≤D2-d2≤10%×D2, where the second direction is the direction in which the minimum distance d2 is located.

7. An electrically conductive connector as claimed in any one of claims 1 to 6, wherein The thickness h1 of the insulating film satisfies: 0.2μm≤h1≤5μm; and / or the thickness h2 of the metal layer satisfies: 0.2μm≤h2≤10μm.

8. An electrically conductive connector as claimed in any one of claims 1 to 7, wherein The relative permittivity ε of the insulating film satisfies: ε≥1.

5.

9. An electrically conductive connector as claimed in any one of claims 1 to 8, wherein, The surface roughness of the insulating film is less than 1 μm.

10. The conductive connector according to any one of claims 1 to 9, characterized in that, At the operating height of the conductive connector, the equivalent capacitance C1 per unit area of ​​the conductive connector satisfies: C1 ≥ 1 pF / mm 2 .

11. The conductive connector of claim 10, wherein, The working height h3 satisfies: 0.1mm≤h3≤0.5mm.

12. An electrically conductive connector as claimed in claim 10 or 11, wherein, At the specified working height, along the direction of the working height, the stress P of the conductive connector satisfies: P < 30 kPa.

13. An electrically conductive connector as claimed in any one of claims 1 to 12, wherein, The insulating film includes a metal oxide layer and a ceramic oxide layer, wherein the ceramic oxide layer covers the side of the metal oxide layer opposite to the metal layer; Alternatively, the insulating film may be made of at least one of polyimide, polyethylene terephthalate, polytetrafluoroethylene, or polyvinylidene fluoride.

14. A mobile terminal, characterized by The device includes a display screen, a floor, and a conductive connector as described in any one of claims 1 to 13, wherein the display screen includes a ground layer, and the ground layer is electrically coupled to the floor via the conductive connector.

15. A method of making an electrically conductive connection, characterized by, The method includes: A metal layer is formed on the outside of the foam; An insulating film is formed on the surface of the metal layer, wherein the relative permittivity of the insulating film is greater than 1.

16. The method of claim 15, wherein the conductive connector is prepared by, The formation of a metal layer on the outside of the foam includes: An aluminum-silicon alloy film is formed on the outside of the foam by aluminum-silicon co-sputtering.

17. The method of claim 16, wherein the conductive connector is prepared by, The process of forming an insulating film on the surface of the metal layer includes: Oxygen is introduced and metallic aluminum is sputtered to form an aluminum oxide layer on the surface of the aluminum-silicon alloy film; A ceramic oxide layer is formed by sputtering on the surface of the alumina.

18. The method for preparing the conductive connector as described in claim 15, characterized in that, The process of forming an insulating film on the surface of the metal layer includes: An organic polymer material solution is coated on the surface of the metal layer; The organic polymer material solution is cured at high temperature to form the insulating film.

19. A method of making an electrically conductive connection as claimed in any one of claims 15 to 18, wherein, The formation of an insulating film on the surface of the metal layer includes such that the minimum distance d1 between the edge of the projection of the metal layer and the edge of the projection of the insulating film satisfies the following condition with respect to the dimension D1 of the projection of the insulating film in a first direction: 1%×D1≤D1-d1≤10%×D1, where the first direction is the direction in which the minimum distance d1 is located.

20. A method of making an electrically conductive connection as claimed in any one of claims 15 to 19, wherein, The method further includes: A substrate layer is formed on the outside of the foam, and the substrate layer is an insulating material layer; The metal layer is formed on the surface of the substrate layer.

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