Manufacturing method of electrode patch

Abstract

The invention provides a manufacturing method of an electrode patch, which comprises the following steps of: S1, providing a flexible circuit board which is provided with at least one conducting strip and at least one pair of conducting pads which are arranged on the same side; s2, providing at least one temperature sensing unit arranged corresponding to the conductive pad pair, the temperature sensing unit comprising a bare chip having a bottom conductive layer and a top conductive layer, and a lead, the bottom surface conductive layer of the bare chip is conductively adhered to one of the pair of conductive bonding pads, and the top surface conductive layer of the bare chip is electrically connected with the other one of the pair of conductive bonding pads through a lead; s3, sealing the temperature sensing unit and the conductive bonding pad by using a sealant; and S4, providing a high-molecular material with a high dielectric constant, and attaching the high-molecular material to the conductive sheet in a vapor deposition manner to form a high-molecular dielectric layer. According to the electrode patch, the polymer dielectric layer is used as a dielectric element, and the bare chip is used as the temperature sensing unit, so that the height of the temperature sensing unit packaged by a sealant can be reduced.

Description

Technical Field

[0001] The present application relates to a method for manufacturing an electrode patch for electric field therapy of tumors. Background Art

[0002] Medium frequency alternating electric field therapy has been proven to be an effective method for tumor treatment. In the entire treatment system, the medium frequency alternating voltage is generated by the electric field generator, transmitted to the adapter via a cable, and then transmitted to the electrode patch. The electrode patch is closely attached to the patient's skin surface, coupling to form a therapeutic electric field. The therapeutic electric field is applied alternately in at least two perpendicular directions to interfere with the mitotic process of tumor cells. In the process of electric field transmission, due to the existence of induction heating, the alternating electromagnetic field generates eddy current electricity, which intensifies the molecular motion and then generates losses in tissues with different conductivity. The losses are transmitted outward in the form of heat, and the lower the conductivity of the tissue, the greater the heat generated. The electrode patch used for the tumor electric field needs to be close to the skin, which aggravates the temperature rise effect on the skin surface with lower conductivity. The temperature of the skin should not be exposed to above 41°C for a long time, so it is necessary to monitor the temperature of the skin surface in real time.

[0003] Existing electrode patches usually use thermistors as temperature sensors and ceramic sheets as dielectric sheets. Because the ceramic dielectric sheet has a certain thickness, the temperature sensor is located in the central perforation of the dielectric sheet and the temperature sensor is encapsulated by injecting sealant into the perforation. However, as polymer film materials are used as dielectric elements in electrode patches, their thickness is greatly reduced compared to traditional ceramic dielectric sheets, and the difficulty of the corresponding thermistor installation process has also been greatly increased.

[0004] It is desirable to provide an improved method for manufacturing an electrode patch. Summary of the invention

[0005] The present application provides a method for manufacturing a thin electrode patch.

[0006] Specifically, the present application is implemented through the following technical solutions: a method for manufacturing an electrode patch, comprising the following steps: S1: providing a flexible circuit board, the flexible circuit board having at least one conductive sheet and at least one pair of conductive pads arranged on the same side; S2: providing at least one temperature sensing unit arranged corresponding to the pair of conductive pads, the temperature sensing unit comprising a bare chip having a bottom conductive layer and a top conductive layer and a lead, the bottom conductive layer of the bare chip is conductively adhered to one of the pair of conductive pads and the top conductive layer is electrically connected to the other of the pair of conductive pads through the lead; S3: using a sealant to seal the temperature sensing unit and the conductive pad; S4: providing a polymer material with a high dielectric constant and attaching the polymer material to the conductive sheet by vapor deposition to form a polymer dielectric layer covering the conductive sheet.

[0007] According to an embodiment of the present invention, in step S1, the step after step S1 further includes the step of providing at least one reinforcing plate, wherein the reinforcing plate is adhered to the back side of the flexible circuit board in a manner corresponding to the paired conductive pads.

[0008] According to an embodiment of the present invention, the conductive pad is located in the area surrounded by the conductive disk or on the periphery of the conductive disk.

[0009] According to an embodiment of the present invention, the method further includes step S5: providing an alloy material and depositing the alloy material on the polymer dielectric layer by vapor deposition to form an alloy layer.

[0010] According to an embodiment of the present invention, the vapor deposition method for forming the polymer dielectric layer or the alloy layer is selected from one or more combinations of evaporation, sputtering and ion plating.

[0011] According to an embodiment of the present invention, the projection area of ​​the bare chip is smaller than the area of ​​the conductive pad.

[0012] According to an embodiment of the present invention, the total height of the temperature sensing unit after being sealed by the sealant does not exceed 650 μm.

[0013] According to an embodiment of the present invention, between step S2 and step S3, the method further includes providing at least one annular support plate, and fixing the annular support plate on the flexible circuit board in a manner of surrounding the outer periphery of the corresponding temperature sensing unit.

[0014] According to an embodiment of the present invention, step S3 specifically includes filling sealant into the annular support plate to seal the temperature sensing unit and the conductive pad.

[0015] According to an embodiment of the present invention, the annular support plate is made of epoxy glass cloth laminate and is fixed on the flexible circuit board by bonding or by welding.

[0016] According to an embodiment of the present invention, step S3 further includes the step of: filling a sealant at the interface between the outer periphery of the bottom of the annular support plate and the flexible circuit board.

[0017] The electrode patch of the present application adopts a polymer dielectric layer as a dielectric element and directly uses a bare chip as a temperature sensing unit, which can reduce the height of the temperature sensing unit after sealant packaging, and has no requirements on the thickness of the polymer dielectric layer.

[0018] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a three-dimensional diagram of an electrode patch according to the first embodiment of the present application;

[0020] Figure 2 for Figure 1 A plan view of a flexible circuit board with an electrode patch;

[0021] Figure 3 for Figure 1 A side view of the electrode patch in FIG.

[0022] Figure 4 for Figure 3 An enlarged view of the area within the rectangular frame in FIG.

[0023] Figure 5 A comparison chart of the temperature rise rate of a temperature sensor using a traditional packaging process and a temperature sensing unit packaged using a new process in this application;

[0024] Figure 6 for Figure 3 A three-dimensional assembly diagram of a temperature sensing unit of an electrode patch and a pair of conductive pads;

[0025] Figure 7 is a stereogram of a modified embodiment of the electrode patch in the first embodiment of the present application;

[0026] Figure 8 for Figure 7 A plan view of a flexible circuit board with an electrode patch;

[0027] Fig. 9 is a three-dimensional diagram of an electrode patch according to a second embodiment of the present application;

[0028] Fig.10 for Fig. 9 A plan view of a flexible circuit board with an electrode patch;

[0029] Fig.11 for Fig.10 A side view of the electrode patch in FIG.

[0030] Fig.12 for Fig.11 An enlarged view of the area within the rectangular frame in FIG.

[0031] Fig.13 Schematic diagram of a tumor electric field therapy system according to the present application. DETAILED DESCRIPTION

[0032] Here, exemplary embodiments will be described in detail, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are only examples of devices, systems, equipment and methods consistent with some aspects of the present application.

[0033] like Fig.13 The tumor electric field treatment system 10 shown includes an electric field generator 3 , an adapter 4 electrically connected to the electric field generator 3 , and a plurality of electrode patches 1 electrically connected to the adapter 4 .

[0034] refer to Figures 1 to 3 As shown, the electrode patch 1 of the present application is used in a tumor electric field therapy system 10, and can be applied to the surface of the patient's tumor site for electric field therapy. The electrode patch 1 in the first embodiment of the present application includes a flexible circuit board 11, a polymer dielectric layer 12, a temperature sensing unit 13, a sealant 14 and a reinforcing plate 15. The flexible circuit board 11 is located at the bottom layer as a supporting layer and has a large area. The polymer dielectric layer 12 covers the front of the flexible circuit board 11. The temperature sensing unit 13 is also arranged on the front of the flexible circuit board 11 and avoids the polymer dielectric layer 12. The sealant 14 is used to encapsulate the temperature sensing unit 13, and the reinforcing plate 15 is installed on the back of the flexible circuit board 11 corresponding to the position of the temperature sensing unit 13, which is used to strengthen the rigidity of the flexible circuit board 11 and provide support for the temperature sensing unit 13.

[0035] The flexible circuit board 11 has the characteristics of light weight, thin thickness, bendability, high flexibility, etc. The substrate 111 of the flexible circuit board 11 is made of polyimide or polyester film material, and its shape is not limited. The thickness of the substrate 111 is not more than 300μm. The flexible circuit board 11 also includes a plurality of welding pieces 112 (similar to gold fingers), a conductive piece 113, a pair of conductive pads 114 and a plurality of conductive traces 115 arranged on the front of the substrate 111. The welding piece 112 is directly electrically connected to the electric field generating device 3 or is electrically connected to the electric field generator 3 through the adapter 3 to receive the electric signal for treatment and the DC signal for temperature detection from the electric field generator 3 respectively. The conductive trace 115 is arranged corresponding to the welding piece 112 and is respectively connected to the corresponding conductive piece 113 and the conductive pad 114. The polymer dielectric layer 12 covers the conductive piece 113 and forms a capacitive coupling with the attached body surface. The temperature sensing unit 13 is arranged corresponding to the conductive pad 114 to detect the temperature of the attached body surface.

[0036] The plurality of soldering pads 112 include a first soldering pad 1121 and two second soldering pads 1122. The plurality of conductive traces 115 corresponding to the plurality of soldering pads 112 include a first conductive trace 1151 and two second conductive traces 1152. The first conductive traces 1151 are respectively electrically connected to the first soldering pad 1121 and the conductive sheet 113. The second conductive traces 1152 are respectively electrically connected to the second soldering pads 1122 and the corresponding conductive pads 114. The second soldering pads 1122, the conductive sheet 113, the first soldering pads 1121 and the conductive pads 114 are all located on the same side of the flexible circuit board 11. The first conductive trace 1151 and the second conductive trace 1152 are arranged in layers in the substrate 111 of the flexible circuit board 11 (not shown) and are not distributed in the same layer. The first conductive trace 1151 is arranged in a layer of the substrate 111 close to the patient's skin, and the second conductive trace 1152 is arranged in a layer away from the patient's skin, and the first welding piece 1121 and the conductive piece 113, and the second welding piece 1122 and the conductive pad 114 are electrically connected through vias. The first welding piece 1121 receives an alternating electric signal from an electric field generating device (not shown) and transmits it to the conductive piece 113 through the first conductive trace 1151; the second welding piece 1122 receives a direct current from the electric field generating device (not shown) and transmits it to the conductive pad 114 through the corresponding second conductive trace 1152, thereby providing an electric signal to the temperature sensing unit 13 electrically connected to the conductive pad 114.

[0037] In this embodiment, the two conductive pads 114 are located in the area surrounded by the conductive sheet 113. Figure 2 An open area 1131 is formed at the center of the substrate 111 (shaded area in the figure), and two conductive pads 114 are located in the open area 1131 and are spaced apart from the conductive sheet 113. The soldering sheet 112, the conductive sheet 113 and the conductive pads 114 can be made of the same metal material and have the same thickness, and the thickness is not greater than 50 μm; they can also be disposed on the substrate 111 by etching or bonding.

[0038] refer to Figure 3 to Figure 4As shown, the function of the polymer dielectric layer 12 is similar to that of the existing ceramic dielectric sheet, and is used as a dielectric element to generate capacitive coupling to apply an alternating electric field to the patient. The polymer dielectric layer 12 at least covers the conductive sheet 113 of the flexible circuit board 11 and avoids the open area 1131. The polymer dielectric layer 12 is made of a polymer material with non-fixed crystal orientation, high flexibility and high toughness, and has a high dielectric constant and low dielectric loss. The dielectric constant of the polymer dielectric layer 12 is not less than 20, and the dielectric strength is not less than 40V / μm to avoid breakdown under normal applied voltage. The polymer dielectric layer 12 can be a ternary copolymer based on a relaxor ferroelectric, such as a vinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene copolymer or a vinylidene fluoride-trifluoroethylene-chlorofluoroethylene copolymer, or a piperazine-biuret copolymer polyamide film. The polymer dielectric layer 12 can be formed on the surface of the conductive sheet 113 by vapor deposition such as evaporation, sputtering and ion plating, or by printing, spraying or casting. In this embodiment, the polymer dielectric layer 12 is formed on the surface of the conductive sheet 113 by vacuum sputtering. The thickness of the polymer dielectric layer 12 does not exceed 300 μm.

[0039] The temperature sensing unit 13 includes a bare chip 131 and a lead 132 which are arranged corresponding to the conductive pad 114. The bare chip 131 is a square-shaped thermistor chip and has a bottom conductive layer 1311 and a top conductive layer 1312. The lead 132 is connected to the top conductive layer 1312 and is led out. A pair of conductive pads 114 includes a first conductive pad 1141 and a second conductive pad 1142. The bottom conductive layer 1311 of the bare chip 131 is bonded and fixed to the first conductive pad 1141 and electrically connected. The top conductive layer 1312 is bonded to the lead 132 and electrically connected to the second conductive pad 1142 through the lead 132. Then, the temperature sensing unit 13 is encapsulated as a whole on the surface of the flexible circuit board 11 by the sealant 14. The sealant 14 can use a curing agent with a low expansion coefficient, low water absorption rate and low fluidity, which can prevent it from flowing to the conductive sheet 113 or the polymer dielectric layer 12 when sealing the temperature sensor unit 13 and the corresponding conductive pad 114, causing the surface of the conductive sheet 113 away from the flexible circuit board 11 to be uneven, resulting in uneven distribution of the polymer dielectric layer 12 and affecting the application of the electric field. The sealant 14 can use a curing sealant with low fluidity and biosafety, which can be cured and formed by high temperature or light of a specific wavelength. After forming, it has excellent shock resistance and electrical corrosion resistance. The material is preferably modified epoxy resin. The reinforcement plate 15 is provided to facilitate the surface mounting process of the temperature sensor unit 13, preferably polyimide, with a thickness of no more than 100 μm, and a projected area of ​​no less than the projected area of ​​the temperature sensor unit 13, but in other embodiments, the reinforcement plate 15 can be replaced by appropriately increasing the thickness of the substrate 111 of the flexible circuit board 11.

[0040] The temperature sensing unit 13 is a bare chip 131 without an external packaging shell. Since the external packaging shell can reduce the overall height, in this embodiment, the total height of the temperature sensing unit 13 after the packaging sealant 14 is no more than 650μm, which can be adapted to the electrode patch 1 that uses polymer film materials as dielectric elements and has an extremely thin overall thickness. In addition, the bare chip 131 without external packaging can be closer to the temperature measurement area and the temperature measurement is more accurate. Figure 5 As shown, compared with the temperature sensor packaged by the traditional packaging process, the temperature sensing unit 13 in the electrode patch of the present application greatly reduces the height of the packaged product and shortens the contact distance between the temperature sensing unit 13 and the human body. In addition, due to the high thermal conductivity of the sealant 14 used, the temperature detection can be faster, the temperature data can be fed back in time, the safety of the system is improved, the voltage adjustment range is shortened, the fluctuation amplitude of the therapeutic electric field voltage applied by the tumor electric field is reduced, and the average electric field strength is improved.

[0041] refer to Figure 6 As shown, the projection area of ​​the bare chip 131 is slightly smaller than the area of ​​the first conductive pad 1141 bonded thereto, so that the bare chip 131 can be supported at the bottom by the first conductive pad 1141 to prevent the bare chip 131 from being damaged due to the bending of the electrode patch 1. The conductive silver paste (not shown) is used as an adhesive between the bare chip 131 and the first conductive pad 1141 and is evenly applied to the bottom and surroundings of the bare chip 131, and the height of the conductive silver paste (not shown) around the bare chip 131 does not exceed 1 / 2 of the height of the bare chip 131. The conductive silver paste (not shown) has excellent conductivity and can achieve fixed connection and electrical connection between the bare chip 131 and the first conductive pad 1141.

[0042] The diameter of the lead 132 is not greater than 0.05 mm. The setting process of the lead 132 is as follows: the lead 132 is formed into a sphere at one end by electronic sparking, and then the sphere is bonded to the top conductive layer 1312 of the bare chip 131 by one or both of ultrasonic and hot pressing methods. After the bonding is completed, the equipment wire clamp (not shown) rises rapidly to the highest degree of the preset arc, so that the lead 132 moves at high speed to the second conductive pad 1142 for pressure point welding, and then the tail wire is pulled off to complete the welding. The fixing order of the lead 132 can be from the top conductive layer 1312 of the bare chip 131 to the second conductive pad 1142, or vice versa. The position of the lead 132 on the top conductive layer 1312 of the bare chip 131 can be set arbitrarily. In this embodiment, the lead 132 is placed on the side close to the second conductive pad 1142 at the center of the top conductive layer 1312 of the bare chip 131, in order to better reduce the wire bonding height. The lead wire 132 may be formed by combining a plurality of conductive wires, and the position where the lead wire 132 is welded to the second conductive pad 1142 may also be arbitrary.

[0043] After the lead 132 is fixed, the temperature sensing unit 13 is sealed and cured at high temperature. The bare chip 131, the lead 132 and the two conductive pads 114 are wrapped with a curing sealant 14 with a low expansion coefficient and low water absorption. Since the sealant 14 has low fluidity, it can form a solid with excellent pressure resistance, waterproof ability and corrosion resistance after high-temperature curing to protect the internal sealed components. The sealant 14 is preferably a modified epoxy resin material, which has the characteristics of fast low-temperature curing, strong corrosion resistance, strong pressure resistance, and high thermal conductivity. It has excellent material reliability at 100°C, can provide good adhesion, and has biological safety, and can be used in medical products.

[0044] After the sealant 14 is cured, the temperature sensing unit 13 is encapsulated on the flexible circuit board 11. The overall height of the sealant 14 and the temperature sensing unit 13 is no more than 650 μm, and the maximum height difference between the sealant 14 and the polymer dielectric layer 12 is only 350 μm, that is, the maximum height of the encapsulated temperature sensing unit 13 protruding from the polymer dielectric layer 12 is only 350 μm, thereby realizing temperature detection under ultra-thin materials and avoiding the need to rely on the height of ceramic dielectric elements to cure the package in traditional processes. The process is convenient and fast, which is conducive to the stability and mass production of product performance.

[0045] It is understandable that the position of the temperature sensing unit 13 of the electrode patch 1 on the flexible circuit board 11 can be set arbitrarily, that is, the relative position of the conductive sheet 113 and the conductive pad 114 can be flexibly set according to needs. Figure 7 and Figure 8 As shown, as a simple transformation of the electrode patch 1, unlike the electrode patch 1, the temperature sensing unit (not shown) of the electrode patch 1' is arranged on the periphery of the conductive sheet 113', that is, the conductive pad 114' of the flexible circuit board 11' is arranged on the periphery of the conductive sheet 113', and accordingly, the second conductive trace 1152' connected to the conductive pad 114' can be arranged on the same layer close to the front side of the substrate 111' as the first conductive trace 1151', and the open area 1131 is no longer arranged at the center of the conductive sheet 113', and the polymer dielectric layer 12' can cover the conductive sheet 113' in its entirety, and other structures remain unchanged, and reference can be made to the previous content, which will not be repeated here.

[0046] The present application also provides a method for manufacturing an electrode patch 1, comprising the following steps:

[0047] S1: providing a flexible circuit board 11, wherein the flexible circuit board 11 has at least one conductive sheet 113 and at least one pair of conductive pads 114 arranged on the same side;

[0048] S2: providing at least one temperature sensing unit 13 corresponding to the conductive pad 114, the temperature sensing unit 13 comprising a bare chip 131 having a bottom conductive layer 1311 and a top conductive layer 1312 and a lead 132, the bare chip 131 is conductively adhered to one of the conductive pads 114 through the bottom conductive layer 1311 and the top conductive layer 1312 is electrically connected to the other one of the conductive pads 114 through the lead 132;

[0049] S3: Use a sealant 14 to seal the temperature sensing unit 13 and the pair of conductive pads 114;

[0050] S4: providing a polymer material with a high dielectric constant and attaching the polymer material to the conductive sheet 113 by vapor deposition to form a polymer dielectric layer 12 covering the conductive sheet 113 .

[0051] In step S1, the flexible circuit board 11 also has a plurality of welding pieces 112 electrically connected to external wires (not shown) and a plurality of conductive traces 115 respectively connecting the welding pieces 112 and the conductive pieces 113 and the welding pieces 112 and the conductive pads 114. The conductive pads 114 can be arranged in the open area 1131 surrounded by the conductive pieces 113, or can be arranged on the periphery of the conductive pieces 113. The flexible circuit board 11 is made of polyimide, and the thickness of the flexible circuit board 11 does not exceed 300 μm.

[0052] After step S1 , at least one reinforcing plate 15 may be provided and adhered to the back surface of the flexible circuit board 11 in a manner corresponding to the corresponding conductive pads 114 .

[0053] In step S2, the bottom conductive layer 1311 of the bare chip 131 is conductively adhered to the corresponding conductive pad 114 through a conductive silver paste (not shown); one end of the lead 132 is bonded to the top conductive layer 1312 of the bare chip 131, and the other end is welded to another corresponding conductive pad 114. The diameter of the lead 132 is less than or equal to 0.05 mm. The bare chip 131 is a thermistor chip. The total height of the bare chip 131 after being sealed by the sealant 14 does not exceed 650 μm.

[0054] In step S4, the material of the polymer dielectric layer 12 is a polymer with a dielectric constant of not less than 20 and a dielectric strength of not less than 40V / μm to avoid breakdown under normal applied voltage. The polymer is a polymer with relaxor ferroelectric behavior, which can be a vinyl fluoride polymer, such as P(VDF-TrFE-CTFE), P(VDF-TrFE-CFE) or P(VDF-TrFE-CFE-CTFE), and can be a polyamide composite material, such as piperazine-biuret Biuret copolymer polyamide. The thickness of the polymer dielectric layer 12 does not exceed 300μm. The vapor deposition method for forming the polymer dielectric layer 12 can be selected from evaporation, sputtering or ion plating.

[0055] After step S4, step S5 may also be included: providing an alloy material and depositing the alloy material on the polymer dielectric layer 12 by vapor deposition to form an alloy layer (not shown). The alloy material may be one or more of zinc-aluminum alloy, zinc-copper alloy, silver, or graphite, and the thickness of the alloy layer is not more than 50 μm. The electrode patch 1 is also provided with a biosafety protection layer (not shown) in contact with the human body, such as a conductive gel, and the polymer dielectric layer 12 and the biosafety protection layer (not shown) cannot be directly bonded, so the alloy layer (not shown) is covered on the polymer dielectric layer 12, and then the alloy layer (not shown) and the biosafety protection layer (not shown) are bonded through an adhesive layer (not shown) to achieve the setting of the biosafety protection layer (not shown). The vapor deposition method for forming the alloy layer (not shown) can be selected from evaporation, sputtering or ion plating, and the same vapor deposition method as that for forming the polymer dielectric layer 12 can be selected, or a vapor deposition method different from that for forming the polymer dielectric layer 12 can be selected.

[0056] The temperature sensing unit 13 on the flexible circuit board 11, 11' of the electrode patch 1, 1' of the present application directly adopts the thermistor bare chip 131 without an external encapsulation shell. The overall height of the encapsulated temperature sensing unit 13 and the sealant 14 is relatively low, thereby realizing the temperature detection under the electrode patch 1 having a polymer dielectric layer 12 in the form of a thin film, and avoiding the need to use the height of ceramic dielectric elements to solidify the encapsulated temperature sensing unit 13 in the traditional process. The process is convenient and fast, and is conducive to the stability and mass production of product performance.

[0057] refer to Figures 9 to 12As shown, the present application also provides a second embodiment of the electrode patch 2. The electrode patch 2 in the second embodiment is similar to the electrode patch 1 in the first embodiment. The electrode patch 2 includes a flexible circuit board 21, a polymer dielectric layer 22, a temperature sensing unit 23, a sealant 24 and a reinforcing plate 25. The flexible circuit board 21 includes a substrate 211, a welding piece 212 disposed on the front of the substrate 211, a conductive sheet 213 and a conductive pad 214, and conductive traces 215 arranged in layers in the substrate 211. The conductive pad 214 is located in an open area 2131 at the center of the conductive sheet 213. The temperature sensing unit 23 is electrically connected to the conductive pad 214. The polymer dielectric layer 22 covers the conductive sheet 213. The soldering piece 212 includes a first soldering piece 2121 and two second soldering pieces 2122. The conductive trace 215 corresponding to the soldering piece 112 includes a first conductive trace 2151 and two second conductive traces 2152. The first conductive trace 1151 electrically connects the first soldering piece 2121 and the conductive piece 213. The second conductive trace 2152 electrically connects the second soldering piece 2122 and the corresponding conductive pad 214. The reinforcing plate 25 is installed on the back of the flexible circuit board 21 at the position corresponding to the temperature sensing unit 23, and is used to strengthen the rigidity of the flexible circuit board 21 to support the temperature sensing unit 23.

[0058] Among them, unlike the temperature sensing unit 13 in the first embodiment which only has a bare chip 131, the temperature sensing unit 23 is a package, including a thermistor (not shown) and a package shell (not numbered). Except for the temperature sensing unit 23, the other structures mentioned above are exactly the same as the electrode patch 1 in the first embodiment. Please refer to the relevant content of the electrode patch 1 in the first embodiment, which will not be repeated here. It can be understood that the position of the temperature sensing unit 23 can also be set arbitrarily, and the conductive pad 214 can be set on the periphery of the conductive sheet 123, similar to Figure 8 shown.

[0059] The overall height of the temperature sensing unit 23 in this embodiment is higher than that of the temperature sensing unit 13 in the first embodiment. In order to facilitate the sealing glue 24 to encapsulate the temperature sensing unit 23, the electrode patch 2 in this embodiment further includes an annular support plate 26. The annular support plate 26 is located in the open area 2131 and surrounds the temperature sensing unit 23. The sealant 24 encapsulates the temperature sensing unit 23 in the annular support plate 26, and the annular support plate 26 can prevent the sealant 24 from overflowing onto the conductive sheet 213.

[0060] The temperature sensing unit 23 uses a thermistor with a negative temperature coefficient, and has a ground terminal (not shown) and a signal terminal (not shown), which are respectively welded and connected to a corresponding pair of conductive pads 214. The annular support plate 26 is in a circular ring shape, and the annular support plate 26 is a hard material with a certain rigidity and thickness, preferably an epoxy glass cloth laminate, which is processed into a hollow ring shape that runs through the top and bottom and is fixed to the front of the flexible circuit board 21 by bonding, or is welded to the front of the flexible circuit board 21 by setting a pad below it. The annular support plate 26 is arranged around the outer periphery of the temperature sensing unit 23, and together with the flexible circuit board 21, it forms a receiving cavity 261 for accommodating the temperature sensing unit 23, which is convenient for the temperature sensing unit 23 to be potted with the sealant 24, wherein the top of the annular support plate 26 is not lower than the top surface of the temperature sensing unit 23. The annular support plate 26 is spaced from the conductive sheet 213 and the polymer dielectric layer 22 to prevent the sealant 24 from adhering to the conductive sheet 213 when the sealant 24 is glued to the bottom of the outer periphery of the annular support plate 26.

[0061] The sealant 24 uses a curing agent with fluidity and biosafety, which can be cured and formed by high temperature or light of a specific wavelength. After forming, it has excellent shock resistance and electrical corrosion resistance. Preferably, it is a single-component epoxy resin or polyurethane acrylate. The sealant 24 is filled into the accommodating cavity 261 and fully wraps the temperature sensing unit 23. The height of the filled sealant 24 can be slightly higher than the top surface of the annular support plate 26, but it cannot overflow to the surface of the conductive sheet 213. After the filling is completed, the temperature sensing unit 23 can be sealed by curing and forming.

[0062] The present application also provides a method for manufacturing an electrode patch 2, comprising the following steps:

[0063] S1: providing a flexible circuit board 21, wherein the flexible circuit board 21 has at least one conductive sheet 213 and at least one pair of conductive pads 214 arranged on the same side;

[0064] S2: providing at least one temperature sensing unit 23 corresponding to a pair of conductive pads 214, and setting the temperature sensing unit 23 on the flexible circuit board 21 by welding with the corresponding pair of conductive pads 214;

[0065] S3: providing an annular support plate 26, and fixing the annular support plate 26 on the flexible circuit board 21 in a manner of being arranged around the outer periphery of the corresponding temperature sensing unit 23;

[0066] S4: Use the sealant 24 to seal the temperature sensing unit 23 until the sealant 24 completely wraps the temperature sensing unit 23 located in the annular support plate 26 and then solidifies the sealant 24;

[0067] S5: providing a polymer material with a high dielectric constant and attaching the polymer material to the conductive sheet 213 by sputtering to form a polymer dielectric layer 22 covering the conductive sheet 213 .

[0068] In step S1, the flexible circuit board 21 also has a plurality of welding pieces 212 electrically connected to external wires (not shown) and a plurality of conductive traces 215 respectively connecting the welding pieces 212 and the conductive pieces 213 and the welding pieces 212 and the conductive pads 214. The conductive pads 214 can be arranged in the area surrounded by the conductive pieces 213 or at the periphery of the conductive pieces 213. The flexible circuit board 21 is made of polyimide, and the thickness of the flexible circuit board 21 does not exceed 300 μm.

[0069] After step S1 , at least one reinforcing plate 25 may be provided and adhered to the back surface of the flexible circuit board 21 in a manner corresponding to the corresponding pair of conductive pads 214 .

[0070] In step S3 , the annular support plate 26 is made of epoxy glass cloth laminate and is fixed to the flexible circuit board 21 by bonding or welding.

[0071] In step S4, the process also includes filling a sealant 24 at the interface between the outer periphery of the bottom of the annular support plate 26 and the flexible circuit board 21. The sealant 24 is a curing adhesive, which can be cured by high temperature or light.

[0072] In step S5, the material of the polymer dielectric layer 22 is a polymer with a dielectric constant of not less than 20 and a dielectric strength of not less than 40V / μm to avoid breakdown under normal applied voltage. The polymer is a polymer with relaxor ferroelectric behavior, which can be a vinyl fluoride polymer, such as P(VDF-TrFE-CTFE), P(VDF-TrFE-CFE) or P(VDF-TrFE-CFE-CTFE), or a polyamide composite material, such as piperazine-biuret copolymer polyamide. The thickness of the polymer dielectric layer 22 does not exceed 300μm.

[0073] After step S5, step S6 may also be included: providing an alloy material and depositing the alloy material on the polymer dielectric layer 22 by vapor deposition to form an alloy layer (not shown). The alloy material may be one or more of zinc-aluminum alloy, zinc-copper alloy, silver, or graphite, and the thickness of the alloy layer is not greater than 50 μm. The electrode patch 2 is also provided with a biosafety protection layer (not shown) in contact with the human body, such as a conductive gel, and the polymer dielectric layer 22 and the biosafety protection layer (not shown) cannot be directly bonded, so the alloy layer (not shown) is covered on the polymer dielectric layer 3, and then the alloy layer (not shown) and the biosafety protection layer (not shown) are bonded through an adhesive layer (not shown) to achieve the setting of the biosafety protection layer (not shown).

[0074] The electrode patch 2 of the present application forms a receiving cavity 261 surrounding the temperature sensing unit 23 by setting an annular support plate 26 on the flexible circuit board 21, which facilitates the temperature sensing unit 23 to be sealed with glue, with low cost, stable process and simple manufacturing. Similarly, there is no requirement for the thickness of the polymer dielectric layer 22 on the flexible circuit board 21, which can meet the temperature measurement requirements of the ultra-thin electrode patch 2. It is understandable that the temperature sensing unit 23 in this embodiment can also adopt the temperature sensing unit 13 with only a bare chip in the first embodiment.

[0075] The above is only a preferred implementation mode of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A method for manufacturing an electrode patch, characterized in that: The following steps are involved: S1: providing a flexible circuit board, wherein the flexible circuit board has at least one conductive sheet and at least one pair of conductive pads arranged on the same side; S2: providing at least one temperature sensing unit corresponding to the pair of conductive pads, the temperature sensing unit comprising a bare chip having a bottom conductive layer and a top conductive layer and leads, the bottom conductive layer of the bare chip being conductively adhered to one of the pair of conductive pads and the top conductive layer being electrically connected to the other of the pair of conductive pads through the leads; S3: Using a sealant to seal the temperature sensing unit and the conductive pad; S4: providing a polymer material with a high dielectric constant and attaching the polymer material to the conductive sheet by vapor deposition to form a polymer dielectric layer covering the conductive sheet.

2. The method for manufacturing an electrode patch according to claim 1, characterized in that: The method further includes the step of providing at least one reinforcing plate after step S1, wherein the reinforcing plate is adhered to the back side of the flexible circuit board in a manner corresponding to the pairs of conductive pads.

3. The method for manufacturing an electrode patch according to claim 1, characterized in that: The conductive disk is located in the area surrounded by the conductive disk or on the periphery of the conductive disk.

4. The method for manufacturing an electrode patch according to claim 1, characterized in that: The method further comprises step S5: providing an alloy material and depositing the alloy material on the polymer dielectric layer by vapor deposition to form an alloy layer.

5. The method for manufacturing an electrode patch according to claim 4, characterized in that: The vapor deposition method for forming the polymer dielectric layer or the alloy layer is selected from one or more combinations of evaporation, sputtering and ion plating.

6. The method for manufacturing an electrode patch according to claim 1, characterized in that: The projection area of ​​the bare chip is smaller than the area of ​​the conductive pad.

7. The method for manufacturing an electrode patch according to claim 1, characterized in that: The total height of the temperature sensing unit after being sealed by the sealant does not exceed 650 μm.

8. The method for manufacturing an electrode patch according to claim 1, characterized in that: Between step S2 and step S3, the method further includes providing at least one annular support plate and fixing the annular support plate on the flexible circuit board in a manner of surrounding the outer periphery of the corresponding temperature sensing unit.

9. The method for manufacturing an electrode patch according to claim 8, characterized in that: Step S3 specifically includes filling sealant into the annular support plate to seal the temperature sensing unit and the conductive pad.

10. The method for manufacturing an electrode patch according to claim 8, characterized in that: The annular support plate is made of epoxy glass cloth laminate and is fixed to the flexible circuit board by bonding or welding.

11. The method for manufacturing an electrode patch according to claim 8, characterized in that: Step S3 also includes the step of: filling the sealant at the interface between the outer periphery of the bottom of the annular support plate and the flexible circuit board.

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