Double-sided thin film inductor and manufacturing method thereof

Abstract

The present invention discloses a double-sided thin film inductor and a manufacturing method thereof. Inductance circuits are manufactured on both the front and back sides of an insulating substrate, and the front inductance circuit and the back inductance circuit are connected through conductive through holes that penetrate the front and back sides of the insulating substrate. In this way, the manufacturing of the front inductance circuit and the back inductance circuit of the insulating substrate can be completed simultaneously by using a yellow light process (the upper and lower inductance circuits are completed simultaneously), which greatly improves the manufacturing efficiency. Compared with the manufacturing of the inductance circuit in the prior art, the manufacturing efficiency is doubled. The structure in which the upper and lower layers of the inductance circuit sandwich the insulating substrate in the middle expands the application range of the inductance circuit. The inductance circuits on both sides of the substrate can improve the inductance value more than the conventional manufacturing of the inductance circuit on only one side of the insulating substrate. The conductive through holes are filled in the insulating substrate by optical fiber laser and printing. Due to the large available aperture area and easy manufacturing, the yield rate can be greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of inductors, and in particular to a double-sided thin film inductor and a manufacturing method thereof. Background Art

[0002] With the rapid development of information technology, people's dependence on technology is increasing day by day, and the field of radio frequency communications is also undergoing earth-shaking changes. Due to its wide range of applications, it has brought very ideal market prospects and has always been favored by people. As a very common passive device, thin film inductors are common in modules in circuits, especially in circuit modules such as radio frequency matching circuits and amplifiers. How to solve the problems of quality factor and self-resonance frequency of magnetic core inductors while ensuring that the inductance value meets the needs of actual circuits requires the design of a new type of inductor product to meet this market demand. Existing ordinary thin film inductors generally adopt a laminated method, and their structure and manufacturing process still have the following disadvantages:

[0003] First, the manufacturing process of traditional thin-film inductors is one layer at a time, with the lower layer of circuits connecting to the upper layer of circuits, and the manufacturing process is lengthy and inefficient.

[0004] Second, the via layer of the upper and lower layers must be produced using a yellow light process, which can easily lead to poor conduction or open circuits due to the gap between the upper and lower layers, or unclean development causing residues on the electrodes, thus affecting the yield. Summary of the invention

[0005] In order to solve the above technical problems, the present invention proposes a double-sided thin film inductor and a method for manufacturing the same. In addition to improving the efficiency of traditional thin film inductors, the structure in which the upper and lower layers of circuits sandwich an insulating substrate in the middle expands the scope of circuit application. The circuits on both sides of the substrate can increase the inductance value more than the traditional circuits on only one side of the substrate.

[0006] The technical solution of the present invention is achieved in this way:

[0007] A double-sided thin film inductor, comprising a square block-shaped insulating substrate, the insulating substrate having a front side and a back side, a front side electrode extending along the X-axis direction is formed on the front side close to the left and right sides of the insulating substrate, a front side inductor circuit is formed in the middle of the front side of the insulating substrate, and the front side inductor circuit is electrically connected to the front side electrode;

[0008] A back electrode extending along the X-axis direction is formed on the back surface near the left and right sides of the insulating substrate, and a back inductor circuit is formed in the middle of the back surface of the insulating substrate, and the back inductor circuit is electrically connected to the back electrode;

[0009] The front inductor circuit and the back inductor circuit are connected via at least one conductive through hole connecting the front and back sides of the insulating substrate;

[0010] The front inductor circuit and the back inductor circuit are covered with an insulating protective layer;

[0011] Side electrodes are respectively formed on two side elevations extending along the X-axis direction on the insulating substrate, the side electrodes extend toward the back side of the insulating substrate and overlap the edge of the back electrode, and the side electrodes extend toward the front side of the insulating substrate and overlap the edge of the front electrode;

[0012] The side electrode is plated with a copper layer, the copper layer is plated with a nickel layer, the nickel layer extends to cover the front electrode and the back electrode, a tin layer is formed on the nickel layer to completely cover the nickel layer, and the tin layer is connected to the end face of the insulating protective layer.

[0013] Furthermore, a marking layer is printed on the insulating protection layer on the front side of the insulating substrate.

[0014] Furthermore, the conductive through hole includes a through hole connecting the front side and the back side of the insulating substrate, and the through hole is filled with printed silver paste.

[0015] Furthermore, the front inductor circuit, the back inductor circuit, the front electrode and the back electrode each include a sputtered metal layer and a rack-plated metal layer rack-plated on the sputtered metal layer.

[0016] Furthermore, the insulating protective layer is a photosensitive resin slurry layer.

[0017] Furthermore, the front inductor circuit and the back inductor circuit are both arranged in a planar spiral shape.

[0018] A method for manufacturing a double-sided thin film inductor comprises the following steps:

[0019] a. Cut out a large insulating substrate according to the design, and cut out frame lines extending along the X-axis direction and frame lines extending along the Y-axis direction on the front and back sides of the insulating substrate, respectively, so as to divide the front and back sides of the insulating substrate into square grids;

[0020] b. pre-dividing the square grid on the insulating substrate into a plurality of inductor units according to a regular arrangement, and cutting a through hole connecting the front and back sides of the insulating substrate in each inductor unit;

[0021] c. printing silver paste on the insulating substrate to fill the through holes to form conductive through holes;

[0022] d. sputtering metal material on the front and back sides of the insulating substrate by vacuum sputtering to form a sputtered metal layer;

[0023] e. Covering the front and back sides of the insulating substrate processed in steps a to d with a photosensitive film;

[0024] f. A photomask having a certain circuit pattern is arranged on an insulating substrate, and the circuit pattern is left on the photosensitive film on the front and back sides of the insulating substrate by exposure using a parallel light source exposure machine. The circuit pattern is composed of a plurality of unit patterns corresponding to a plurality of inductor units, and each unit pattern includes a front inductor pattern corresponding to a preset front inductor circuit located in the middle of the front side, and a front electrode pattern corresponding to a preset front electrode extending along the X-axis direction located on the left and right sides of the front inductor pattern, and the front inductor pattern is connected to the preset front electrode pattern; and also includes a back inductor pattern corresponding to a preset back inductor circuit located in the middle of the back side, and a back electrode pattern corresponding to a preset back electrode extending along the X-axis direction located on the left and right sides of the back inductor pattern, and the back inductor pattern is connected to the back electrode pattern; the front inductor pattern and the back inductor pattern are both connected to the conductive through hole;

[0025] g. Remove the unnecessary photosensitive film by developing to expose the sputtered metal layer corresponding to the circuit patterns on the front and back sides of the insulating substrate;

[0026] h. using a rack plating technique to rack plate a rack-plated metal layer (26) on the sputtered metal layer, and then using a film removal technique to remove the photosensitive film in the area outside the circuit pattern;

[0027] i. Using chemical etching to etch away the sputtered metal layer outside the circuit pattern to form a front inductor circuit and a front electrode, a back inductor circuit and a back electrode;

[0028] j. Using laser technology to scribe the insulating substrate processed in steps a to i, cutting out a plurality of fold lines extending along the X-axis direction and fold lines extending along the Y-axis direction, wherein the fold lines intersect and are perpendicular to the fold lines, and the insulating substrate is divided into a plurality of square grids corresponding to a plurality of inductor units;

[0029] k. Printing a layer of photosensitive ink as an insulating protective layer on the front and back sides of the insulating substrate processed in steps a to j;

[0030] 1. Expose the front electrode and the back electrode by exposure and development, leaving the area covering the front inductor circuit and the back inductor circuit;

[0031] m. Printing a marking layer on one side of the insulating protective layer treated in steps a to l, and drying and sintering the layer;

[0032] n. Folding the insulating substrate processed in steps a to m into a plurality of strip-shaped semi-finished products in sequence along the folding lines of the insulating substrate; and then sputtering the side surfaces of each of the strip-shaped semi-finished products formed by the folding of the strips using a vacuum sputtering machine to form side electrodes, which are overlapped on the front electrode and the back electrode;

[0033] o, folding the strip semi-finished product processed in steps a to n into a plurality of block-shaped semi-finished products in sequence along the folding lines of the strip semi-finished product; and then plating a layer of metal copper on the side electrodes of each block-shaped semi-finished product by roller plating to form a copper-plated layer; the copper-plated layer is placed on the front electrode and the back electrode;

[0034] p. Plate a layer of metal nickel on the copper-plated layer, the front electrode and the back electrode by roller plating to form a nickel-plated layer, which can completely cover the copper-plated layer, the front electrode and the back electrode;

[0035] q. A layer of metallic tin is plated on the outside of the nickel-plated layer by roller plating to form a tin-plated layer, which can completely cover the nickel-plated layer.

[0036] Furthermore, in the above step b, the through holes are formed by fiber laser, in the above step c, the holes are filled by printing and vacuum suction, in the above step j, the insulating protection layer is printed by screen printing and exposure, and in the above step l, the identification layer is printed by screen printing.

[0037] Furthermore, the sputtering target material of the sputtered metal layer in the above step d is metal titanium and metal copper; the material of the plated metal layer in the above step h is pure copper; the material of the photosensitive ink in the above step j is photosensitive resin slurry; the material of the marking layer described in the above step l is resin slurry.

[0038] The beneficial effects of the present invention are:

[0039] Compared with the thin film inductor in the prior art, the double-sided thin film inductor and the manufacturing method produced by the present invention have the following advantages: ① By using optical fiber laser to punch holes on the insulating substrate, a path connecting the front and back sides of the insulating substrate is formed; ② There are corresponding inductance circuits on the front and back sides of the insulating substrate, which can improve the inductance value; ③ The inductance circuit is formed by hanging plating to ensure the accuracy of the inductance value; ④ After the inductance circuit is completed, a laser machine is used to scribe the particle lines to ensure the accuracy of the particles; in short, the double-sided thin film inductor produced by the present invention can be widely used in the production of various circuits. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a schematic structural diagram of an insulating substrate after being processed in steps a and b of the present invention;

[0041] Figure 2 This is a schematic diagram of the structure of the insulating substrate after being processed in step c of the present invention;

[0042] Figure 3 This is a schematic structural diagram of the insulating substrate after being processed in step d of the present invention;

[0043] Figure 4 This is a schematic structural diagram of the insulating substrate after being processed in step e of the present invention;

[0044] Figure 5 is a schematic structural diagram of an insulating substrate after being processed in step f of the present invention;

[0045] Figure 6 is a schematic structural diagram of an insulating substrate after being processed in step g of the present invention;

[0046] Figure 7 is a schematic structural diagram of the insulating substrate after being processed in step h of the present invention;

[0047] Figure 8 is a schematic structural diagram of the insulating substrate after being processed in step i of the present invention;

[0048] Fig. 9 is a schematic structural diagram of an insulating substrate after being processed in step j of the present invention;

[0049] Fig.10 is a schematic structural diagram of an insulating substrate after being processed in steps k and l of the present invention;

[0050] Fig.11 This is a schematic structural diagram of the front side of the insulating substrate after being processed in step m of the present invention;

[0051] Fig.12 This is a schematic diagram of the structure of the strip-shaped semi-finished product obtained after the step n of the present invention;

[0052] Fig.13 This is a schematic diagram of the structure of the block-shaped semi-finished product obtained after the step o of the present invention;

[0053] Fig.14 The schematic diagram of the structure of the double-sided thin film inductor obtained after the processing of steps p and q of the present invention;

[0054] Fig.15 It is a schematic diagram of the cross-sectional structure of the double-sided thin film inductor of the present invention. DETAILED DESCRIPTION

[0055] In order to more clearly understand the technical content of the present invention, the following embodiments are given in detail, the purpose of which is only to better understand the content of the present invention but not to limit the protection scope of the present invention.

[0056] like Fig.15 As shown, a double-sided thin film inductor comprises a square block-shaped insulating substrate 1, wherein the insulating substrate has a front side and a back side, and a front electrode 2 extending along the X-axis direction is formed on the front side close to the left and right sides of the insulating substrate, and a front inductor circuit 3 is formed in the middle of the front side of the insulating substrate, and the front inductor circuit is electrically connected to the front electrode;

[0057] A back electrode 4 extending along the X-axis direction is formed on the back surface near the left and right sides of the insulating substrate, and a back inductor circuit 5 is formed in the middle of the back surface of the insulating substrate, and the back inductor circuit is electrically connected to the back electrode;

[0058] The front inductor circuit and the back inductor circuit are connected via at least one conductive through hole 6 connecting the front and back sides of the insulating substrate.

[0059] The front inductor circuit and the back inductor circuit are covered with an insulating protection layer 7 .

[0060] Side electrodes 8 are respectively formed on two side elevations extending along the X-axis direction of the insulating substrate. The side electrodes extend toward the back side of the insulating substrate and overlap the edge of the back electrode. The side electrodes extend toward the front side of the insulating substrate and overlap the edge of the front electrode.

[0061] The side electrode is plated with a copper layer 9, and the copper layer is plated with a nickel layer 10. The nickel layer extends to cover the front electrode and the back electrode. A tin layer 11 is formed on the nickel layer to completely cover the nickel layer, and the tin layer is connected to the end face of the insulating protective layer.

[0062] In the above structure, inductor circuits are made on both the front and back sides of the insulating substrate, and the front inductor circuit and the back inductor circuit are connected through conductive through holes that penetrate the front and back sides of the insulating substrate. In this way, the yellow light process can simultaneously complete the production of the front inductor circuit and the back inductor circuit of the insulating substrate (the upper and lower inductor circuits are completed at the same time), which greatly improves the production efficiency. Compared with the production of inductor circuits in the prior art, the production efficiency is doubled, and the structure in which the upper and lower layers of inductor circuits sandwich the insulating substrate in the middle expands the application range of the inductor circuit. The inductor circuits on both sides of the substrate can improve the inductance value more than the traditional production of inductor circuits on only one side of the insulating substrate. The conductive through holes are filled in the insulating substrate by optical fiber laser and printing. Due to the large available aperture area and easy production, the yield can be greatly improved.

[0063] Further, the insulating protective layer on the front side of the insulating substrate is printed with a logo layer 12. In this way, the product logo layer is printed on the front side of the insulating substrate, which is easy to identify.

[0064] Furthermore, the conductive through hole includes a through hole 23 connecting the front and back sides of the insulating substrate, and the through hole is filled with silver paste 24 printed therein.

[0065] Furthermore, the front inductor circuit, the back inductor circuit, the front electrode and the back electrode all include a sputtered metal layer 25 and a rack-plated metal layer 26 rack-plated on the sputtered metal layer. In this way, a layer of metal is firstly sputtered to form a sputtered metal layer, and then a layer of metal is plated on the sputtered metal layer by rack plating to form a rack-plated metal layer (inductor circuit), which can ensure the stability of the inductance value.

[0066] Furthermore, the insulating protective layer is a photosensitive resin slurry layer.

[0067] Furthermore, the front inductor circuit and the back inductor circuit are both arranged in a planar spiral shape.

[0068] A method for manufacturing a double-sided thin film inductor comprises the following steps:

[0069] a. See Figure 1 According to the design, a large insulating substrate 1 is cut out, and a frame line 21 extending along the X-axis direction and a frame line 22 extending along the Y-axis direction are cut out on the front and back sides of the insulating substrate, respectively, so that the front and back sides of the insulating substrate are divided into square grids; preferably, the above-mentioned frame lines 21, 22 can be formed by optical fiber laser.

[0070] b. See Figure 1 , the square grid on the insulating substrate is pre-divided into a number of inductor units according to a regular arrangement, and a through hole 23 connecting the front and back sides of the insulating substrate is cut in each inductor unit; preferably, the through hole 23 can be cut by optical fiber laser, so that the usable aperture area is large and the production is easy.

[0071] c. See Figure 2 , printing silver paste 24 on the insulating substrate to fill the through hole to form a conductive through hole 6; preferably, the silver paste can be printed into the through hole on the insulating substrate by printing and filling the hole. Since the available aperture area is large and the manufacturing is easy, the yield can be greatly improved. In specific implementation, the silver paste material can be selected from resin silver, so that the resin silver fills the through hole, and the resin silver on the outer area of ​​the silver hole is ground clean by grinding technology.

[0072] d. See Figure 3 After the front and back sides of the insulating substrate are cleaned, a vacuum sputtering method is used to sputter metal material on the front and back sides of the insulating substrate to form a sputtered metal layer 25; preferably, the sputtered metal material is metal titanium and copper, that is, the sputtering target material of the sputtered metal layer is metal titanium and metal copper.

[0073] e. See Figure 4 , a layer of photosensitive film is covered on the front and back sides of the insulating substrate after being processed in steps a to d; that is, a layer of photoresist is coated on the front and back sides of the insulating substrate, preferably, a photosensitive resin can be used.

[0074] f. See Figure 5 , a photomask having a certain circuit pattern is arranged on an insulating substrate, and the circuit pattern is left on the photosensitive film on the front and back sides of the insulating substrate by exposure using a parallel light source exposure machine, wherein the circuit pattern is composed of a plurality of unit patterns corresponding to a plurality of inductor units, each unit pattern including a front inductor pattern corresponding to a preset front inductor circuit located in the middle of the front side, a front electrode pattern corresponding to a preset front electrode extending along the X-axis direction located on the left and right sides of the front inductor pattern, and the front inductor pattern is connected to the preset front electrode pattern; and also including a back inductor pattern corresponding to a preset back inductor circuit located in the middle of the back side, a back electrode pattern corresponding to a preset back electrode extending along the X-axis direction located on the left and right sides of the back inductor pattern, and the back inductor pattern is connected to the back electrode pattern; the front inductor pattern and the back inductor pattern are both connected to the conductive through hole;

[0075] g. See Figure 6 , removing unnecessary photosensitive films by development to expose the sputtered metal layers corresponding to the circuit patterns on the front and back sides of the insulating substrate; in specific implementation, the insulating substrate treated in steps a to f can be rinsed in a developing solvent to expose the sputtered metal layers corresponding to the circuit patterns on the front and back sides of the insulating substrate.

[0076] h. See Figure 7 , a rack-plated metal layer 26 is plated on the sputtered metal layer by using the rack plating technology, and then the photosensitive film in the area outside the circuit pattern is removed by using the film removal technology; the circuit is plated by the rack plating method to ensure the stability of the inductance value. Preferably, the material of the rack-plated metal layer is pure copper.

[0077] i. See Figure 8 , using chemical etching method, the sputtered metal layer in the area outside the circuit pattern is etched away to form the front inductor circuit 3 and the front electrode 2, the back inductor circuit 5 and the back electrode 4; that is, the positive inductor circuit and the back inductor circuit are connected in series to form an inductance value.

[0078] j. See Fig. 9, laser technology is used to scribe the insulating substrate after the processing in steps a to l, and a plurality of fold lines 27 extending along the X-axis direction and fold grain lines 28 extending along the Y-axis direction are cut out. The fold lines and the fold grain lines are perpendicular to each other, and the insulating substrate is divided into a plurality of square grids corresponding to a plurality of inductor units; the fold lines in the X direction and the fold grain lines in the Y direction can ensure that the inductor is separated into grains in the subsequent process; and after the inductor circuit is completed, a laser machine is used to scribe the grain lines to ensure the accuracy of the grains.

[0079] k. See Fig.10 , printing a layer of photosensitive ink on the front and back of the insulating substrate treated in steps a to i as an insulating protective layer 7; that is, printing a layer of photosensitive ink on the treated rack-plated metal layer, and setting an I-shaped exposure area in each square grid area corresponding to the photosensitive film according to the design requirements; the material of the photosensitive ink is a photosensitive resin slurry;

[0080] 1. See Fig.10 , through exposure and development, the front electrode and the back electrode are exposed, leaving the area covering the front inductor circuit and the back inductor circuit; that is, the excess photosensitive ink is developed away by the development method, leaving the area covering the front inductor circuit and the back inductor circuit.

[0081] M. See Fig.11 A marking layer 12 is printed on the insulating protective layer after the treatment in steps a to k, and then dried and sintered. The material of the marking layer is resin slurry.

[0082] n. See Fig.12 , folding the insulating substrate processed in steps a to m into a plurality of strip-shaped semi-finished products in sequence along the folding lines of the insulating substrate; and then using a vacuum sputtering machine to sputter the side surface of each of the strip-shaped semi-finished products formed by the folding strips to form a side electrode 8, which is overlapped on the front electrode and the back electrode;

[0083] o. See Fig.13 , folding the strip semi-finished product processed in steps a to n into a plurality of block semi-finished products in sequence along the folding line of the strip semi-finished product; and then coating the side electrodes of each block semi-finished product with a layer of metal copper by roller plating to form a copper plating layer 9; the copper plating layer is placed on the front electrode and the back electrode;

[0084] p. See Fig.14 , a layer of metal nickel is plated on the copper-plated layer, the front electrode and the back electrode by roller plating to form a nickel-plated layer 10, and the nickel-plated layer can completely cover the copper-plated layer, the front electrode and the back electrode;

[0085] q. See Fig.14A layer of metallic tin is plated on the outside of the nickel-plated layer by roller plating to form a tin-plated layer 11, which can completely cover the nickel-plated layer.

[0086] The above embodiments are to describe the preferred embodiments of the present invention in detail with reference to the accompanying drawings. Those skilled in the art may make various modifications or changes to the above embodiments without departing from the essence of the present invention, which shall fall within the protection scope of the present invention.

Claims

1. A double-sided thin film inductor, characterized in that: The invention comprises a square block-shaped insulating substrate (1), wherein the insulating substrate has a front side and a back side, and a front electrode (2) extending along the X-axis direction is formed on the front side close to the left and right sides of the insulating substrate, and a front inductor circuit (3) is formed in the middle of the front side of the insulating substrate, and the front inductor circuit is electrically connected to the front electrode; A back electrode (4) extending along the X-axis direction is formed on the back surface close to the left and right sides of the insulating substrate, and a back inductor circuit (5) is formed in the middle of the back surface of the insulating substrate, and the back inductor circuit is electrically connected to the back electrode; The front inductor circuit and the back inductor circuit are connected via at least one conductive through hole (6) connecting the front and back sides of the insulating substrate; The front inductor circuit and the back inductor circuit are covered with an insulating protective layer (7); Side electrodes (8) are respectively formed on two side elevations extending along the X-axis direction on the insulating substrate, the side electrodes extend toward the back side of the insulating substrate and overlap the edge of the back electrode, and the side electrodes extend toward the front side of the insulating substrate and overlap the edge of the front electrode; The side electrode is plated with a copper layer (9), the copper layer is plated with a nickel layer (10), the nickel layer extends to cover the front electrode and the back electrode, a tin layer (11) is formed on the nickel layer to completely cover the nickel layer, and the tin layer is connected to the end face of the insulating protective layer, the front inductor circuit, the back inductor circuit, the front electrode and the back electrode all include a sputtered metal layer (25) and a rack-plated metal layer (26) plated on the sputtered metal layer, a through hole connecting the front and back is opened on the insulating substrate, silver paste (24) is printed on the insulating substrate and filled with the through hole to form a conductive through hole (6), and then the front inductor circuit and the back inductor circuit are simultaneously manufactured through a yellow light process.

2. The double-sided thin film inductor according to claim 1, characterized in that: A marking layer (12) is printed on the insulating protection layer on the front side of the insulating substrate.

3. The double-sided thin film inductor according to claim 1, characterized in that: The conductive through hole comprises a through hole (23) connecting the front side and the back side of the insulating substrate, and the through hole is filled with silver paste (24) printed inside.

4. The double-sided thin film inductor according to claim 1, characterized in that: The insulating protective layer is a photosensitive resin slurry layer.

5. The double-sided thin film inductor according to claim 1, characterized in that: The front inductor circuit and the back inductor circuit are both arranged in a planar spiral shape.

6. A method for manufacturing a double-sided thin film inductor, characterized in that: The steps include: a. cutting out a large insulating substrate (1) according to the design, and cutting out a frame line (21) extending along the X-axis direction and a frame line (22) extending along the Y-axis direction on the front and back sides of the insulating substrate, respectively, so as to divide the front and back sides of the insulating substrate into square grids; b. pre-dividing the square grid on the insulating substrate into a plurality of inductor units according to a regular arrangement, and cutting a through hole (23) in each inductor unit that connects the front and back sides of the insulating substrate; c. printing silver paste (24) on the insulating substrate to fill the through hole, thereby forming a conductive through hole (6); d. sputtering a metal material on the front and back sides of the insulating substrate by a vacuum sputtering method to form a sputtered metal layer (25); e. Covering the front and back sides of the insulating substrate processed in steps a to d with a photosensitive film; f. A photomask having a certain circuit pattern is arranged on an insulating substrate, and the circuit pattern is left on the photosensitive film on the front and back sides of the insulating substrate by exposure using a parallel light source exposure machine. The circuit pattern is composed of a plurality of unit patterns corresponding to a plurality of inductor units, and each unit pattern includes a front inductor pattern corresponding to a preset front inductor circuit located in the middle of the front side, and a front electrode pattern corresponding to a preset front electrode extending along the X-axis direction located on the left and right sides of the front inductor pattern, and the front inductor pattern is connected to the preset front electrode pattern; and also includes a back inductor pattern corresponding to a preset back inductor circuit located in the middle of the back side, and a back electrode pattern corresponding to a preset back electrode extending along the X-axis direction located on the left and right sides of the back inductor pattern, and the back inductor pattern is connected to the back electrode pattern; the front inductor pattern and the back inductor pattern are both connected to the conductive through-hole, and the front inductor circuit and the back inductor circuit are simultaneously manufactured by a yellow light process; g. Remove the unnecessary photosensitive film by developing to expose the sputtered metal layer corresponding to the circuit patterns on the front and back sides of the insulating substrate; h. using a rack plating technique to rack plate a rack-plated metal layer (26) on the sputtered metal layer, and then using a film removal technique to remove the photosensitive film in the area outside the circuit pattern; i. Using a chemical etching method, the sputtered metal layer in the area outside the circuit pattern is etched away to form a front inductor circuit (3) and a front electrode (2), a back inductor circuit (5) and a back electrode (4); j. Using laser technology to scribe the insulating substrate processed in steps a to i, cutting out a plurality of fold lines (27) extending along the X-axis direction and fold lines (28) extending along the Y-axis direction, wherein the fold lines intersect and are perpendicular to the fold lines, and the insulating substrate is divided into a plurality of square grids corresponding to a plurality of inductor units; k. Printing a layer of photosensitive ink on the front and back sides of the insulating substrate processed in steps a to j as an insulating protective layer (7); 1. Expose the front electrode and the back electrode by exposure and development, leaving the area covering the front inductor circuit and the back inductor circuit; m. Printing a marking layer (12) on one side of the insulating protective layer treated in steps a to l, and drying and sintering the layer; n. folding the insulating substrate processed in steps a to m into a plurality of strip-shaped semi-finished products in sequence along the folding lines of the insulating substrate; and then sputtering the side surfaces of each of the strip-shaped semi-finished products formed by folding the strips using a vacuum sputtering machine to form side electrodes (8), which are overlapped on the front electrode and the back electrode; o, folding the strip semi-finished product processed in steps a to n into a plurality of block-shaped semi-finished products in sequence along the folding lines of the strip semi-finished product; and then coating the side electrodes of each block-shaped semi-finished product with a layer of metal copper by roller plating to form a copper-plated layer (9); the copper-plated layer is placed on the front electrode and the back electrode; p. using a roll plating method to plate a layer of metal nickel on the copper-plated layer, the front electrode and the back electrode to form a nickel-plated layer (10), wherein the nickel-plated layer can completely cover the copper-plated layer, the front electrode and the back electrode; q. A layer of metallic tin is plated on the outside of the nickel-plated layer by roller plating to form a tin-plated layer (11), and the tin-plated layer can completely cover the nickel-plated layer.

7. The method for manufacturing a double-sided thin film inductor according to claim 6, characterized in that: In the above step b, the through holes are made by fiber laser, in the above step c, the holes are filled by printing and vacuum suction, in the above step j, the insulating protection layer is printed by screen printing and exposure, and in the above step l, the identification layer is printed by screen printing.

8. The method for manufacturing a double-sided thin film inductor according to claim 6, characterized in that: The sputtering target material of the sputtered metal layer in the above step d is metal titanium and metal copper; the material of the plated metal layer in the above step h is pure copper; the material of the photosensitive ink in the above step j is photosensitive resin slurry; the material of the marking layer described in the above step l is resin slurry.

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