Amorphous wire sensor and method of manufacturing the same

Abstract

The application discloses an amorphous wire sensor and a preparation method thereof. The micro amorphous wire sensor comprises a substrate, a bottom coil, an amorphous wire, an arch coil, a metal pad, an amorphous wire signal lead and a coil signal lead which are connected to the substrate. The bottom coil is connected to the substrate, and the metal pad is arranged on the bottom coil. The amorphous wire extends along the bottom coil, and the end of the amorphous wire is wrapped by the metal pad on the bottom coil to realize electrical connection. The two ends of the arch coil are curved and inclined and extend to the bottom coil. The support layer formed by the curing of the support material is arranged between the arch coil and the bottom coil. The arch coil and the amorphous wire are isolated by the support layer. The amorphous wire signal lead is electrically connected to the metal pad, and the coil signal lead is electrically connected to the arch coil. The application can reduce the volume of the sensor, improve the production efficiency of the sensor and achieve the purpose of mass production of the micro amorphous wire sensor under the premise of ensuring the consistency of the device.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of magnetic sensing, in particular to an amorphous wire sensor and a preparation method thereof. BACKGROUND

[0002] The emergence of giant magneto-impedance (GMI) effect promotes the development of high-precision weak magnetic detection technology. The magnetic sensor based on the GMI effect is widely used in the fields of ocean, aerospace, target survey, medical instruments and military industry. Compared with amorphous thin film, amorphous thin strip and other soft magnetic materials, the amorphous micro-wire has a more significant GMI effect. The GMI sensor with amorphous micro-wire as the magnetic sensitive material has attracted widespread attention in the field of weak magnetic detection due to its high sensitivity, non-contact and almost no hysteresis. In the traditional technology, the amorphous micro-wire as a special-shaped structure of soft magnetic material is usually electrically connected by welding process, and an inductor coil is wound around the amorphous micro-wire to complete the preparation of the magnetic sensor. However, this processing method has the disadvantages of large device size, poor coil consistency and large floating resistance of the welding port. SUMMARY

[0003] Therefore, it is necessary to provide an amorphous wire sensor and a preparation method thereof, which can reduce the size of the sensor, improve the production efficiency of the sensor and achieve the purpose of mass production of the micro amorphous wire sensor under the premise of ensuring the consistency of the device.

[0004] An embodiment of the present application provides a preparation method of an amorphous wire sensor.

[0005] A preparation method of an amorphous wire sensor, comprising the following steps:

[0006] A first metal seed layer, a bottom coil and a first metal sub-pad are prepared on the surface of a substrate in a stacked manner, and an amorphous wire is fixed on the bottom coil and two ends of the amorphous wire are located on the first metal sub-pad, respectively;

[0007] Photoresist is spin-coated to cover the amorphous wire and the bottom coil, and after drying, exposure and development, part of the amorphous wire fixed on the first metal sub-pad is exposed, and the outer glass of the exposed amorphous wire is removed;

[0008] After the photoresist remaining on the amorphous wire and the bottom coil is removed, a support material containing non-photosensitive polyimide is spin-coated on the surface of the substrate, dried to obtain a covering layer, photoresist is spin-coated on the surface of the covering layer, and after drying, exposure and development, a patterned second groove with a curved inner wall is obtained, the patterned second groove separates the covering layer to form a support layer located on the bottom coil and wrapping the amorphous wire and a wrapping layer located on the substrate and wrapping the bottom coil.

[0009] removing the photoresist remained on the support layer and the wrapping layer, baking the support layer and the wrapping layer in an oxygen-free environment to make them imidize;

[0010] sequentially preparing a second metal seed layer, a second metal sub-pad and a plurality of arch-shaped coils laminated and connected on the surface of the support layer and the wrapping layer, the end of the amorphous wire being wrapped between the first metal sub-pad and the second metal sub-pad, the arch-shaped coils extending in a curved shape along the surface of the support layer and covering the amorphous wire.

[0011] In some embodiments, when the first metal seed layer, the bottom coil and the first metal sub-pad are sequentially prepared on the surface of the substrate, the following steps are included:

[0012] preparing the first metal seed layer on the surface of the substrate;

[0013] spinning photoresist on the surface of the first metal seed layer, and obtaining a patterned first groove after drying, exposing and developing;

[0014] preparing the bottom coil and the first metal sub-pad by electroplating in the patterned first groove;

[0015] after removing the remained photoresist, etching to remove the exposed first metal seed layer.

[0016] In some embodiments, the preparation method further satisfies at least one of the following conditions:

[0017] (1) before preparing the first metal seed layer on the substrate, the following step is further included: cleaning the substrate with acetone, isopropyl alcohol and pure water in sequence and then drying;

[0018] (2) the material for preparing the first metal seed layer is Cr and / or Cu;

[0019] (3) the preparation method of the first metal seed layer includes a magnetron sputtering process, wherein the magnetron sputtering power is 600W~700W, and the sputtering rate is 4.22 Å / s~6.59Å / s;

[0020] (4) the thickness of the first metal seed layer is 600Å~2000Å;

[0021] (5) when preparing the bottom coil and the first metal sub-pad by electroplating in the patterned first groove, the electroplating solution is CuSO4 solution, the electroplating current is 0.243A~0.3A, and the electroplating time is 480s~660s.

[0022] In some embodiments, the preparation method further satisfies at least one of the following conditions:

[0023] (1) removing the outer glass of the exposed amorphous wire using HF solution, wherein the concentration of the HF solution is 3% to 5%, and the corrosion time of the HF solution is 30 min to 35 min;

[0024] (2) spin-coating a support material containing non-photosensitive polyimide with a thickness of 40 μm to 60 μm;

[0025] (3) baking the support layer in an oxygen-free environment at a baking temperature gradually increasing from 60°C to 350°C for 9 h to 15 h;

[0026] (4) the thickness of the second metal seed layer is 600 Å to 2000 Å.

[0027] In some embodiments, when the second metal seed layer, the second metal sub-pad and the plurality of arch-shaped coils are sequentially prepared on the surface of the support layer and the wrapping layer in a stacked manner, the method comprises the following steps:

[0028] preparing the second metal seed layer on the surface of the support layer and the wrapping layer, spin-coating photoresist on the second metal seed layer, and baking, exposing and developing the photoresist on the support layer and the part of the photoresist in the adjacent second groove of the support layer to expose part of the second metal seed layer;

[0029] electroplating the second metal sub-pad on the exposed end of the second metal seed layer, wrapping the end of the amorphous wire between the first metal sub-pad and the second metal sub-pad, and preparing the arch-shaped coils on the non-end exposed second metal seed layer;

[0030] removing the photoresist and etching to remove the exposed second metal seed layer.

[0031] In some embodiments, the preparation method further satisfies at least one of the following conditions:

[0032] (1) the second metal seed layer is prepared on the surface of the imidized support layer by a magnetron sputtering process, wherein the magnetron sputtering power is 600 W to 700 W, and the sputtering rate is 4.22 Å / s to 6.59 Å / s;

[0033] (2) when the second metal sub-pad and the arch-shaped coils are electroplated on the exposed end of the second metal seed layer, the electroplating solution is CuSO4 solution, the electroplating current is 0.243 A to 0.3 A, and the electroplating time is 480 s to 660 s.

[0034] In some embodiments, the preparation method further satisfies at least one of the following conditions:

[0035] (1) the thickness of the spin-coated photoresist is 8-12 μm;

[0036] (2) the baking temperature of the photoresist is 100-120 °C, and the baking time is 180-300 s;

[0037] (3) the photoresist is exposed by hard contact exposure, and the exposure dose is 300-600 mj;

[0038] (4) the developing solution for the photoresist is an alkaline solution containing TMAH, and the developing time is 3-6 min.

[0039] (5) when removing the photoresist remaining on the amorphous wire and the bottom coil and the photoresist remaining on the surface of the first metal seed layer, the remaining photoresist is soaked in acetone, and then is cleaned with isopropyl alcohol and pure water in sequence, wherein the soaking time in acetone is 10-20 min; when removing the photoresist remaining on the support layer, the remaining photoresist is soaked in propylene glycol monomethyl ether acetate solution and then is cleaned with pure water.

[0040] An embodiment of the present application provides an amorphous wire sensor.

[0041] An amorphous wire sensor comprises a substrate, a bottom coil, an amorphous wire, an arch-shaped coil, a metal pad, an amorphous wire signal lead and a coil signal lead connected to the substrate; wherein the bottom coil is connected to the substrate, the metal pad is arranged on the bottom coil, the amorphous wire extends along the bottom coil, and the amorphous wire end is electrically connected by being wrapped by the metal pad on the bottom coil, the arch-shaped coil is curved and covers the amorphous wire, the two ends of the arch-shaped coil are curved and inclined and extend to the bottom coil, the two ends of the arch-shaped coil are respectively connected to the bottom coil, the arch-shaped coil and the bottom coil have a support layer formed by curing a support material, the arch-shaped coil and the amorphous wire are isolated by part of the support layer, the height of the support layer from the bottom coil is greater than the diameter of the amorphous wire, the amorphous wire signal lead is electrically connected to the metal pad, and the coil signal lead is electrically connected to the arch-shaped coil.

[0042] In some embodiments, the amorphous wire sensor further comprises a wrapping layer connected to the substrate and wrapping and covering part of the bottom coil, part of the amorphous wire and part of the arch-shaped coil, wherein the metal pad wrapping the amorphous wire end, the top surface of the arch-shaped coil, the amorphous wire signal lead and the coil signal lead are exposed to the wrapping layer.

[0043] In some embodiments, the wrapping layer is formed of a support material containing non-photosensitive polyimide.

[0044] In some embodiments, the top surface of the arch-shaped coil is parallel to the substrate, and two side portions of the top surface are respectively curved in an arc shape, and the top surface width of the arch-shaped coil is greater than the diameter of the amorphous wire.

[0045] And / or, the height of the support layer from the bottom layer coil is 40-60 mu m.

[0046] In some embodiments, the line of the bottom layer coil and the extension direction of the amorphous wire have an included angle in the horizontal plane ranging from 45-60 degrees.

[0047] And / or, the bottom layer coil extends in a strip shape on the substrate as a whole.

[0048] And / or, the substrate is a glass substrate.

[0049] The amorphous wire sensor overcomes the shortcomings of low production efficiency, poor device consistency, large volume and the like of the traditional amorphous wire GMI magnetic sensor, realizes the electrical connection of the amorphous wire and the preparation of the three-dimensional arch-shaped coil based on the MEMS technology, uses the support material containing non-photosensitive polyimide to form a support layer to enhance the stability of the coil, optimizes the structure and preparation process of the three-dimensional coil, reduces the production cost and process complexity, reduces the volume of the amorphous wire sensor under the premise of ensuring the consistency of the device, improves the production efficiency of the sensor, and achieves the purpose of mass production of the micro amorphous wire sensor.

[0050] The preparation method of the amorphous wire sensor of the application realizes the combination of the wire material and the wafer by using the MEMS process, simplifies the preparation process of the three-dimensional arch-shaped coil by using the support material containing non-photosensitive polyimide under the premise of ensuring the performance and consistency, improves the stability of the arch-shaped coil, completes the integration of the arch-shaped coil and the amorphous wire, and realizes the batch manufacturing of the miniaturized amorphous wire sensor. BRIEF DESCRIPTION OF DRAWINGS

[0051] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0052] In order to more completely understand the present application and its beneficial effects, the following will be described with reference to the drawings. In the following description, the same reference numerals represent the same parts.

[0053] Figure 1 The schematic diagram of step S1 in the preparation method of embodiment 1 of the present application is shown.

[0054] Figure 2 Schematic diagram of step S2 in the preparation method described in Embodiment 1 of the present application;

[0055] Figure 3 Schematic diagram of step S3 in the preparation method described in Embodiment 1 of the present application;

[0056] Figure 4 Schematic diagram of step S4 in the preparation method described in Embodiment 1 of the present application;

[0057] Figure 5 Schematic diagram of step S5 in the preparation method described in Embodiment 1 of the present application;

[0058] Figure 6 Schematic diagram of step S6 in the preparation method described in Embodiment 1 of the present application;

[0059] Figure 7 Schematic diagram of step S10 in the preparation method described in Embodiment 1 of the present application;

[0060] Figure 8 Schematic diagram of step S10 in the preparation method described in Embodiment 1 of the present application;

[0061] Figure 9 Schematic diagram of step S11 in the preparation method described in Embodiment 1 of the present application;

[0062] Figure 10 Schematic diagram of step S13 in the preparation method described in Embodiment 1 of the present application;

[0063] Figure 11 Schematic diagram of step S14 in the preparation method described in Embodiment 1 of the present application;

[0064] Figure 12 Schematic diagram of step S15 in the preparation method described in Embodiment 1 of the present application;

[0065] Figure 13 Schematic diagram of step S16 in the preparation method described in Embodiment 1 of the present application;

[0066] Figure 14 Schematic diagram of the amorphous wire sensor structure prepared by the preparation method described in Embodiment 1 of the present application;

[0067] Figure 15 Actual picture of the amorphous wire sensor prepared by the preparation method described in Embodiment 1 of the present application.

[0068] Explanation of reference signs

[0069] 10. Amorphous wire sensor; 100, substrate; 200, bottom coil; 300, amorphous wire; 400, arched coil; 500, metal pad; 600, amorphous wire signal lead; 700, coil signal lead; 801, first metal seed layer; 802, second metal seed layer; 901, 902, 903, photoresist; 1001, patterned first groove; 1002, patterned second groove; 1100, support layer; 1200, wrapping layer. DETAILED DESCRIPTION

[0070] In order to make the above objectives, features and advantages of the present application more apparent, specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. It will be apparent, however, to one skilled in the art that the present application can be practiced without some or all of these details. In other instances, well known process steps have not been described in detail in order to avoid unnecessarily obscuring the present application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0071] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0072] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting", "fixing" and the like should be understood broadly, for example, can be fixed connection, can also be detachable connection, or integral; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium; can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0073] In the present application, unless otherwise explicitly specified and limited, a first feature is "on" or "under" a second feature can mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature "over", "above" and "on top of" the second feature can mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature. The first feature "under", "below" and "underneath" the second feature can mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is horizontally lower than the second feature.

[0074] In the description of the present application, the meaning of "one or more" is more than one, the meaning of "two or more" is more than two, greater than, less than, more than, etc. are understood as not including the number, above, below, within, etc. are understood as including the number. If it is described that the first, second is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or the sequence of indicated technical features.

[0075] In this paper, "optionally", "optional", "optional" means optional, that is, optional from "yes" or "no" two parallel schemes. If there are multiple "optional" in a technical solution, unless otherwise specified, and there is no contradiction or mutual restriction, each "optional" is independent of each other. In this application, "optionally contains", "optionally contains" and the like, means "contains or does not contain". "Optional component X" means that component X exists or does not exist, or means that it contains or does not contain component X.

[0076] In this application, the numerical interval (i.e. the numerical range) is involved, unless otherwise specified, the distribution of the optional values in the numerical interval is considered to be continuous, and includes the two numerical endpoints (i.e. the minimum value and the maximum value) of the numerical interval, and every value between the two numerical endpoints. If there is no special instruction, when the numerical interval only points to the integer in the numerical interval, including the two endpoint integers of the numerical range and every integer between the two endpoints, it is equivalent to directly listing every integer. When multiple numerical ranges are provided to describe characteristics or properties, these numerical ranges can be combined. In other words, unless otherwise indicated, the numerical range disclosed in this application should be understood to include any and all sub-ranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, a percentage, a ratio, etc. The "numerical interval" allows the percentage interval, the ratio interval, the ratio interval, etc. Quantitative interval is allowed to be broad.

[0077] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application. The use herein of the terms "and / or" includes a set of one or more associated listed items.

[0078] The embodiment of the present application provides a kind of amorphous wire sensor 10, to solve the problem of device size, coil consistency is poor, welding port resistance float is large etc. when amorphous microfilament as a special-shaped structure soft magnetic material is generally realized electrical connection by welding process in traditional technology. The amorphous wire sensor 10 will be described below in conjunction with the drawings.

[0079] The amorphous wire sensor 10 provided by the embodiment of the present application is exemplified, please refer to Figure 14 As shown, Figure 14 The structure schematic diagram of the amorphous wire sensor 10 provided by the embodiment of the present application. In order to more clearly illustrate the structure of the amorphous wire sensor 10, the amorphous wire sensor 10 will be introduced below in conjunction with the drawings.

[0080] Exemplarily, please refer to Figure 14 As shown, an amorphous wire sensor 10 includes substrate 100 and bottom coil 200 connected on substrate 100, amorphous wire 300, arch coil 400, metal pad 500, amorphous wire signal lead 600 and coil signal lead 700. Wherein, bottom coil 200 is connected to substrate 100, and metal pad 500 is arranged on bottom coil 200. Amorphous wire 300 extends along bottom coil 200, and the end of amorphous wire 300 is wrapped by metal pad 500 on bottom coil 200 to realize electrical connection. Arch coil 400 is curved and covers amorphous wire 300, and the two ends of arch coil 400 are bent and inclined and extend to bottom coil 200. Arch coil 400 and bottom coil 200 have support layer 1100 formed by curing of support material, and arch coil 400 and amorphous wire 300 are isolated by part of support layer 1100. Amorphous wire signal lead 600 is electrically connected with metal pad 500. Coil signal lead 700 is electrically connected with arch coil 400.

[0081] In some embodiments, the amorphous wire sensor 10 further includes wrapping layer 1200. The wrapping layer 1200 is connected to the substrate 100 and wraps part of the bottom coil 200, part of the amorphous wire 300 and part of the arch coil 400. Wherein, the metal pad 500 wrapping the end of the amorphous wire 300, the top surface of the arch coil 400, the amorphous wire signal lead 600 and the coil signal lead 700 are exposed to the wrapping layer.

[0082] In some embodiments, the wrapping layer 1200 is formed of a support material containing a non-photosensitive polyimide.

[0083] In some embodiments, the top surface of the arched coil 400 is parallel to the substrate 100, and two side portions of the top surface are respectively curved in an arc shape, and the width of the top surface of the arched coil 400 is greater than the diameter of the amorphous wire 300.

[0084] In some embodiments, the height of the support layer 1100 from the bottom layer coil 200 is 40 μm to 60 μm. The height of 40 μm to 60 μm of the support layer 1100 can achieve full coverage of the amorphous wire 300, and the arched coil 400 and the amorphous wire 300 can also be isolated by the partial support layer 1100.

[0085] In some embodiments, the line of the bottom layer coil 200 and the extension direction of the amorphous wire 300 have an included angle in the horizontal plane, and the included angle ranges from 45° to 60°.

[0086] In some embodiments, the bottom layer coil 200 extends in a strip shape on the substrate 100 as a whole.

[0087] In some embodiments, the substrate 100 is a glass substrate.

[0088] An embodiment of the present application provides a preparation method of an amorphous wire sensor 10.

[0089] It should be noted that, in the present text, unless otherwise specified, each reaction step can be performed in the order described herein or can not be performed in the order described herein. For example, each reaction step can include other steps, and the order of the reaction steps can also be appropriately changed. This can be determined by a person skilled in the art according to common knowledge and experience. Preferably, the reaction method in the present text is performed in sequence.

[0090] A preparation method of an amorphous wire sensor 10 includes the following steps:

[0091] A first metal seed layer 801, a bottom layer coil 200 and a first metal sub-pad are prepared on the surface of a substrate 100, and an amorphous wire 300 is fixed on the bottom layer coil 200, and two ends of the amorphous wire 300 are respectively located on the first metal sub-pad.

[0092] A photoresist is spin-coated to cover the amorphous wire 300 and the bottom layer coil 200, and after drying, exposure and development, part of the amorphous wire 300 fixed on the first metal sub-pad is exposed, and the outer glass of the exposed amorphous wire 300 is removed.

[0093] After removing the residual photoresist on the amorphous wire 300 and the underlying coil 200, a supporting material containing non-photosensitive polyimide is spin-coated on the surface of the substrate 100, and after drying, a covering layer 1300 is obtained. A photoresist 902 is spin-coated on the surface of the covering layer 1300, and after drying, exposure, and development, a patterned second groove 1002 with a curved inner wall is obtained. The patterned second groove 1002 divides the covering layer 1300 to form a supporting layer 1100 located on the underlying coil 200 and wrapping the amorphous wire 300, and a wrapping layer 1200 located on the substrate 100 and wrapping the underlying coil 200.

[0094] The residual photoresist 902 on the supporting layer 1100 and the wrapping layer 1200 is removed, and the supporting layer 1100 and the wrapping layer 1200 are baked in an oxygen-free environment to be imidized.

[0095] On the surfaces of the imidized supporting layer 1100 and the wrapping layer 1200, a second metal seed layer 802, a second metal sub-pad, and a plurality of arched coils 400 are sequentially prepared in a stacked and connected manner. The end of the amorphous wire 300 is wrapped between the first metal sub-pad and the second metal sub-pad, and the arched coils 400 extend in a curved shape along the surface of the supporting layer 1200 and cover the amorphous wire 300.

[0096] It should be noted that the patterned second groove 1002 includes a plurality of second grooves. Two adjacent second grooves distributed along the direction perpendicular to the amorphous wire 300 are used to prepare one arched coil 400. That is, the two side portions of the arched coil 400 respectively extend in a curved shape along the inner wall of the second groove, and the middle portion of the arched coil 400 extends along the surface of the supporting layer 1100 between the adjacent second grooves, so that the arched coil 400 is generally in an approximate "ji" shape structure.

[0097] In this application, through wet etching, the supporting layer 1200 formed by a supporting material such as non-photosensitive polyimide presents a certain inclination degree towards the side wall of the patterned second groove 1002, so as to ensure the uniformity of the subsequent photoresist covering on the three-dimensional structure surfaces of the supporting layer 1100 and the wrapping layer 1200. The preparation of the three-dimensional arched coil 400 can be completed without high aspect ratio columns. The imidized non-photosensitive polyimide has better physical properties than the traditional AZ-based photoresist or SU-8-based photoresist, which improves the mechanical stability of the amorphous wire sensor 10. Some supporting materials such as non-photosensitive polyimide are imidized as the supporting layer 1100 instead of the sacrificial layer. Compared with the three-dimensional coil without the supporting layer 1100 in the traditional technology, the risk of coil rupture caused by deformation stress during the photoresist removal process in the traditional technology is avoided.

[0098] In some embodiments, when the first metal seed layer 801, the underlying coil 200, and the first metal sub-pad are sequentially prepared on the surface of the substrate 100, the following steps are included:

[0099] A first metal seed layer 801 is prepared on the surface of the substrate 100.

[0100] A photoresist 901 is spin-coated on the surface of the first metal seed layer 801, and after baking, exposure and development, a patterned first groove 1001 is obtained.

[0101] A bottom coil 200 and a first metal sub-pad are prepared by electroplating in the patterned first groove 1001.

[0102] After removing the residual photoresist 901, the exposed first metal seed layer 801 is etched and removed.

[0103] In some embodiments, the preparation method satisfies at least one of the following conditions:

[0104] (1) Before the first metal seed layer 801 is prepared on the substrate 100, the substrate 100 is cleaned with acetone, isopropyl alcohol and pure water in sequence and then dried;

[0105] (2) The material for preparing the first metal seed layer 801 is Cr and / or Cu;

[0106] (3) The preparation method of the first metal seed layer 801 includes a magnetron sputtering process, wherein the magnetron sputtering power is 600W-700W, and the sputtering rate is 4.22 Å / s-6.59 Å / s;

[0107] (4) The thickness of the first metal seed layer 801 is 600 Å-2000 Å;

[0108] (5) When the bottom coil 200 and the first metal sub-pad are prepared by electroplating in the patterned first groove 1001, the electroplating solution is a CuSO4 solution, the electroplating current is 0.243A-0.3A, and the electroplating time is 480s-660s.

[0109] In some embodiments, the preparation method satisfies at least one of the following conditions:

[0110] (1) The outer layer glass of the exposed amorphous wire 300 is removed using an HF solution, wherein the concentration of the HF solution is 3%-5%, and the HF solution etching time is 30min-35min;

[0111] (2) The thickness of the support material containing non-photosensitive polyimide is 40μm-60μm;

[0112] (3) When the support layer 1100 is baked at high temperature in an oxygen-free environment, the baking temperature is increased from 60℃ to 350℃ in a gradient, and the baking time is 9h-15h;

[0113] (4) The thickness of the second metal seed layer 802 is 600A~2000A.

[0114] In some embodiments, the support material containing the non-photosensitive polyimide can be all non-photosensitive polyimide, that is, the proportion of non-photosensitive polyimide in the support material is 100%.

[0115] In some embodiments, when the second metal seed layer 802, the second metal sub-pad and the plurality of arch-shaped coils 400 are sequentially prepared on the surface of the imidized support layer 1100 and the wrapping layer 1200 in a stacked and connected manner, the following steps are included:

[0116] The second metal seed layer 802 is prepared on the surface of the imidized support layer 1100 and the wrapping layer 1200, and the photoresist 903 is spin-coated on the second metal seed layer 802. The support layer 1100 and the portion of the photoresist at the second groove adjacent to the support layer 1100 are subjected to drying, exposure and development to expose a portion of the second metal seed layer 802;

[0117] The second metal sub-pad is prepared by electroplating on the end-exposed second metal seed layer 802, and the end of the amorphous wire 300 is wrapped between the first metal sub-pad and the second metal sub-pad. The arch-shaped coil 400 is prepared on the non-end-exposed second metal seed layer 802;

[0118] After the photoresist 903 is removed and the exposed second metal seed layer 802 is etched, a plurality of arch-shaped coils 400 covering the amorphous wire 300 can be obtained.

[0119] In some embodiments, the above preparation method satisfies at least one of the following conditions:

[0120] (1) The thickness of the photoresist 901, 902 and 903 is 8μm~12μm;

[0121] (2) The baking temperature for drying the photoresist 901, 902 and 903 is 100℃~120℃, and the baking time is 180s~300s;

[0122] (3) The exposure dose is 300mj~600mj when the photoresist 901, 902 and 903 is exposed by hard contact exposure;

[0123] (4) The developing solution for developing the photoresist 901, 902 and 903 is an alkaline solution containing TMAH, and the developing time is 3min~6min.

[0124] (5) When removing the photoresist remaining on the amorphous wire 300 and the bottom layer coil 200 and the photoresist remaining on the surface of the first metal seed layer 801, the remaining photoresist is soaked in acetone, and then isopropanol and pure water are used for cleaning in sequence, wherein the soaking time of acetone is 10 min to 20 min; when removing the photoresist remaining on the support layer 1100, the remaining photoresist is soaked in propylene glycol monomethyl ether acetate (PMA) solution and then cleaned with pure water.

[0125] For example, one specific example of the present application provides a preparation method of an amorphous wire sensor 10. The preparation method of the amorphous wire sensor 10 comprises the following steps:

[0126] Step S1, preparing a first metal seed layer 801 on the surface of a substrate 100, as shown in Figure 2 .

[0127] Step S2, spin-coating a photoresist 901 on the surface of the first metal seed layer 801, and obtaining a patterned first groove 1001 after drying, exposure and development, as shown in Figure 3 .

[0128] Step S3, electroplating to prepare a bottom layer coil 200 and a first metal sub-pad in the patterned first groove 1001, as shown in Figure 4 .

[0129] Step S4, removing the photoresist 901 remaining on the surface of the first metal seed layer 801, and etching the exposed first metal seed layer 801 to remove the exposed first metal seed layer 801, as shown in Figure 5 .

[0130] Step S5, fixing the amorphous wire 300 on the bottom layer coil 200, and arranging the two ends of the amorphous wire 300 on the first metal sub-pads, as shown in Figure 6 .

[0131] Step S6, spin-coating a photoresist to cover the amorphous wire 300 and the bottom layer coil 200, and exposing part of the amorphous wire 300 fixed on the first metal sub-pad after drying, exposure and development.

[0132] Step S7, removing the outer glass layer of the exposed amorphous wire 300.

[0133] Step S8, removing the remaining photoresist.

[0134] Step S9, spin-coating a support material containing non-photosensitive polyimide, and drying to obtain a cover layer 1300, as shown in Figure 7As shown in FIG. 10, the surface of the cover layer 1300 is spin-coated with photoresist 902, and after baking, exposure and development, a patterned second groove 1002 with a curved inner wall is obtained. The patterned second groove 1002 separates the cover layer 1300 into a support layer 1100 located on the bottom coil 200 and wrapping the amorphous wire 300, and a wrapping layer 1200 located on the substrate 100 and wrapping the bottom coil 200. See FIG. 11. Figure 8 As shown in FIG. 12.

[0135] Step S10, remove the photoresist 902 remaining on the support layer 1100 and the wrapping layer 1200. See FIG. 13. Figure 9 As shown in FIG. 14.

[0136] Step S11, bake the support layer 1100 and the wrapping layer 1200 at high temperature in an oxygen-free environment to imidize them.

[0137] Step S12, prepare a second metal seed layer 802 on the surface of the imidized support layer 1100 and the wrapping layer 1200. See FIG. 15. Figure 10 As shown in FIG. 16.

[0138] Step S13, spin-coat photoresist 903 on the second metal seed layer 802, and bake, expose and develop the photoresist on the support layer 1100 and the part of the photoresist at the second groove adjacent to the support layer 1100 to expose part of the second metal seed layer. See FIG. 17. Figure 11 As shown in FIG. 18.

[0139] Step S14, electroplate a second metal sub-pad and a plurality of arch-shaped coils 400 on the exposed second metal seed layer 802 at the end, and wrap the end of the amorphous wire 300 between the first metal sub-pad and the second metal sub-pad, and prepare arch-shaped coils 400 on the non-exposed second metal seed layer. See FIG. 19. Figure 12 As shown in FIG. 20.

[0140] Step S15, remove the photoresist 903 to expose the second metal seed layer 802, and use etching liquid to remove the exposed second metal seed layer 802. See FIG. 21. Figure 13 As shown in FIG. 22.

[0141] Step S16, slice bonding.

[0142] In the preparation method of the present application, the support layer 1100 formed by the support material containing non-photosensitive polyimide is used to support the three-dimensional arched coil 400. Compared with the traditional photoresist, the support material containing non-photosensitive polyimide has a higher viscosity. In the development process, the support material containing non-photosensitive polyimide with a relatively thick or excessively high viscosity can slow down the diffusion speed of the developing solution, so that the support layer 1100 is more likely to form an inclined surface in the development process. By controlling the development time of the support material containing non-photosensitive polyimide, the side wall of the support layer 1100 can form an inclined surface, which is used to prepare the arched coil 400. In the subsequent step of spin-coating the photoresist, the photoresist can be uniformly distributed on the inclined surface. The preparation of the three-dimensional arched coil 400 can be completed by one-time electroplating. The preparation process is simple and convenient. The support layer 1100 after imidization has excellent mechanical properties, which can be used as the support of the arched coil 400, and can significantly improve the stability of the three-dimensional coil. Compared with the three-dimensional micro coil prepared based on the traditional MEMS process, the arched coil 400 prepared by the present application does not need to form a high-aspect-ratio column structure through long-time electroplating. The present application is a column-free structure, which can reduce the process cost and complexity, and improve the production efficiency and quality of the device.

[0143] In some embodiments, the preparation method described above further satisfies at least one of the following conditions:

[0144] In some embodiments, before the first metal seed layer 801 is prepared on the substrate 100 in step S1, the substrate 100 is sequentially cleaned with acetone, isopropyl alcohol and pure water, and then dried.

[0145] In some embodiments, in step S1, the preparation material of the first metal seed layer 801 is Cr and / or Cu.

[0146] In some embodiments, in step S1, the preparation method of the first metal seed layer 801 includes a magnetron sputtering process, wherein the magnetron sputtering power is 600W-700W, and the sputtering rate is 4.22 Å / s-6.59 Å / s.

[0147] In some embodiments, in step S1, the thickness of the first metal seed layer 801 is 600 Å-2000 Å.

[0148] In some embodiments, in step S2, the thickness of the photoresist 901 spin-coated on the surface of the first metal seed layer 801 is 8 μm-12 μm.

[0149] In some embodiments, in step S2, the baking temperature during drying is 100°C-120°C, and the baking time is 180s-300s.

[0150] In some embodiments, in step S2, a hard contact exposure is used for exposure, and the exposure dose is 300mj-600mj.

[0151] In some embodiments, in step S2, the developing solution is a TMAH-based alkaline solution, and the developing time is 3min-6min.

[0152] In some embodiments, in step S3, when the bottom coil 200 and the first metal sub-pad are prepared by electroplating in the patterned first groove 1001, the electroplating solution is a CuSO4 solution, the electroplating current is 0.243A-0.3A, and the electroplating time is 480s-660s.

[0153] In some embodiments, in step S4, acetone is used to remove the residual photoresist, and the acetone soaking time is 10min-20min.

[0154] In some embodiments, in step S6, the thickness of the spin-coated photoresist is 8μm-12μm.

[0155] In some embodiments, in step S6, the baking temperature during baking is 100℃-120℃, and the baking time is 180s-300s.

[0156] In some embodiments, in step S6, a hard contact exposure is used for exposure, and the exposure dose is 300mj-600mj.

[0157] In some embodiments, in step S6, the developing solution is a TMAH-based alkaline solution, and the developing time is 3min-6min.

[0158] In some embodiments, in step S7, an HF solution is used to remove the outer glass of the exposed amorphous wire 300, and the concentration of the HF solution is 3%-5%, and the HF solution etching time is 30min-35min.

[0159] In some embodiments, in step S8, acetone is used to remove the residual photoresist, and isopropanol and pure water are used for cleaning, and the acetone soaking time is 10min-20min.

[0160] In some embodiments, in step S9, the thickness of the support material containing non-photosensitive polyimide is 40μm-60μm.

[0161] In some embodiments, in step S9, the thickness of the photoresist 902 spin-coated on the surface of the support layer 1100 is 8μm-12μm.

[0162] In some embodiments, in step S9, the baking temperature during baking is 100-120°C, and the baking time is 180-300s.

[0163] In some embodiments, in step S9, the exposure is performed by hard contact exposure, and the exposure dose is 300-600mj.

[0164] In some embodiments, in step S9, the developing solution is a TMAH-based alkaline solution, and the developing time is 3-6min.

[0165] In some embodiments, in step S10, propylene glycol monomethyl ether acetate (PMA) solution is used to remove the residual photoresist on the support layer 1100.

[0166] In some embodiments, in step S11, the baking temperature of the support layer 1100 is increased from 60°C to 350°C in an oxygen-free environment, and the baking time is 9-15h.

[0167] In some embodiments, in step S12, a second metal seed layer 802 is prepared on the surface of the support layer 1100 by magnetron sputtering, wherein the magnetron sputtering power is 600-700W, and the sputtering rate is 4.22-6.59Å / s.

[0168] In some embodiments, in step S12, the thickness of the second metal seed layer 802 is 600-2000Å.

[0169] In some embodiments, in step S13, the thickness of the photoresist 903 spin-coated on the second metal seed layer 802 is 8-12μm.

[0170] In some embodiments, in step S13, the baking temperature during baking is 100-120°C, and the baking time is 180-300s.

[0171] In some embodiments, in step S13, the exposure is performed by hard contact exposure, and the exposure dose is 300-600mj.

[0172] In some embodiments, in step S13, the developing solution is a TMAH-based alkaline solution, and the developing time is 3-6min.

[0173] In some embodiments, in step S14, the second metal sub-pads and the arc-shaped coil 400 are prepared by electroplating on the second metal seed layer 802 exposed at the end, the electroplating solution is CuSO4 solution, the electroplating current is 0.243-0.3A, and the electroplating time is 480-660s.

[0174] In some embodiments, in step S15, the photoresist 903 is removed using acetone to expose the second metal seed layer 802, and the surface of the second metal seed layer 802 is cleaned with isopropyl alcohol and pure water, wherein the acetone soaking time is 10 min to 20 min.

[0175] In some embodiments, the photoresist 901, 902, 903 in the present application can be a positive photoresist, for example, a model AZP4620 photoresist.

[0176] The preparation method of the amorphous wire sensor 10 of the present application realizes the combination of the wire material and the wafer by using the MEMS process. On the premise of ensuring performance and consistency, the preparation process of the three-dimensional micro coil can be simplified, the coil stability can be improved, the integration of the arch-shaped coil 400 and the amorphous wire 300 can be completed, and the batch manufacturing of the miniaturized amorphous wire sensor can be realized when the support layer 1100 is formed by using the support material containing non-photosensitive polyimide.

[0177] Embodiment 1

[0178] The present embodiment provides a miniaturized amorphous wire sensor with an arch-shaped coil 400.

[0179] The miniaturized amorphous wire sensor of the present embodiment is prepared by using the following preparation method.

[0180] A preparation method of a miniaturized amorphous wire sensor, comprising the following steps:

[0181] Step S1, clean the glass substrate 100 with acetone, isopropyl alcohol and pure water in sequence, and dry it for standby, as shown in Figure 1 .

[0182] Step S2, prepare a first metal seed layer 801 on the surface of the glass substrate 100 by using a magnetron sputtering process, the first metal seed layer 801 is a copper seed layer, the sputtering process parameters are: sputtering power is 600 W, sputtering rate is 6.59 Å / s, thickness of the first metal seed layer 801 is 2000 Å, as shown in Figure 2 .

[0183] Step S3, spin 10 μm AZP4620 photoresist on the surface of the first metal seed layer 801, dry it at 110℃ for 200 s, use hard contact exposure, exposure dose is 300 mj to 600 mj, develop it with an alkaline solution containing TMAH for 5 min to obtain a patterned first groove 1001, as shown in Figure 3 .

[0184] Step S4, a bottom coil 200 and a first metal sub-pad are prepared by electroplating in the patterned first groove 1001 using a CuSO4 solution, the electroplating current is 0.243 A, and the electroplating time is 500 s, as shown in FIG. 4. Figure 4 The first metal sub-pad is not shown in FIG. 3. Figure 4 The first metal sub-pad is not shown in FIG. 3.

[0185] Step S5, the residual AZP4620 photoresist 901 is removed by soaking in acetone for 10 min, and the first metal seed layer 801 is removed by etching using a copper etching solution after the metal seed layer is exposed, as shown in FIG. 5. Figure 5 The first metal seed layer is not shown in FIG. 4.

[0186] Step S6, an amorphous wire 300 with a diameter of 30 μm is fixed on the bottom coil 200, and the two ends of the amorphous wire 300 are located on the first metal sub-pads, as shown in FIG. 6. Figure 6 The amorphous wire 300 is a radial cross-sectional view thereof. Figure 6 The amorphous wire 300 is a radial cross-sectional view thereof.

[0187] Step S7, an AZP4620 photoresist with a thickness of 10 μm is spin-coated to cover the amorphous wire 300 and the bottom coil 200, and is baked at a temperature of 110 °C for 200 s, and is exposed by hard contact exposure with an exposure dose of 500 mj, and is developed by using an alkaline solution containing TMAH for 5 min, so that the amorphous wire 300 fixed on the first metal sub-pads is exposed.

[0188] Step S8, the ends of the amorphous wire 300 are etched by using an HF solution with a concentration of 4% for 30 min to remove the outer glass of the exposed amorphous wire 300.

[0189] Step S9, the residual AZP4620 photoresist is removed by soaking in acetone for 10 min, and isopropanol and pure water are used for cleaning.

[0190] Step S10, a non-photosensitive polyimide with a thickness of 50 μm is spin-coated on the glass substrate 100, and is baked to obtain a cover layer 1300, as shown in FIG. 10. An AZP4620 photoresist 902 with a thickness of 10 μm is spin-coated on the surface of the cover layer 1300, and is baked at a temperature of 110 °C for 200 s, and is exposed by hard contact exposure with an exposure dose of 500 mj, and is developed by using an alkaline solution containing TMAH for 5 min to obtain a patterned second groove 1002 with a curved inner wall, as shown in FIG. 11. Figure 7 The patterned second groove is not shown in FIG. 9. Figure 8 The patterned second groove is not shown in FIG. 9.

[0191] Step Sll, using propylene glycol monomethyl ether acetate (PMA) solution to remove the photoresist 902 remaining on the support layer 1100 and the wrapping layer 1200, see Figure 9

[0192] Step S12, baking the support layer 1100 and the wrapping layer 1200 in an oxygen-free environment at high temperature to make them imidize.

[0193] Step S13, using a magnetron sputtering process to prepare a second metal seed layer 802 on the surface of the support layer 1100 and the wrapping layer 1200, the second metal seed layer 802 is a copper seed layer, the sputtering process parameters are: sputtering power is 600 W, sputtering rate is 6.59 Å / s, and the thickness of the second metal seed layer 802 is 500 Å, see Figure 10

[0194] Step S14, spin-coating 10 μm thick AZP4620 photoresist 903 on the second metal seed layer 802, baking at 110°C for 200 s, using hard contact exposure, exposure dose is 500 mj, using an alkaline solution containing TMAH to develop for 5 min, removing part of the photoresist on the support layer 1100 and the second groove adjacent to the support layer 110 to expose part of the second metal seed layer, see Figure 11

[0195] Step S15, using CuSO4 solution to electroplate to prepare a second metal sub-pad and a plurality of arc-shaped coils 400 on the exposed second metal seed layer 802 at the end, the electroplating current is 0.3 A, the electroplating time is 480 s, the end of the amorphous wire 300 is wrapped between the first metal sub-pad and the second metal sub-pad, and the arc-shaped coil 400 is prepared on the non-exposed second metal seed layer, see Figure 12

[0196] Step S16, using acetone to soak for 10 min to remove the photoresist 903 and expose the second metal seed layer 802, and then using copper etching solution to etch and remove the exposed second metal seed layer 802, see Figure 13

[0197] Step S17, slicing and bonding according to the preset size requirements. The amorphous wire sensor 10 is prepared, see Figure 14 ​​​​​As shown, the amorphous wire 300 extends along the bottom coil 200, and the ends of the amorphous wire 300 are wrapped by the metal pads 500 on the bottom coil 200 to achieve electrical connection, the arcuate coil 400 is bent and covers the amorphous wire 300, the two ends of the arcuate coil 400 are bent and inclined and extend to be connected to the bottom coil 200, the arcuate coil 400 and the bottom coil 200 have a support layer 1100 formed by curing of a support material, and the arcuate coil 400 and the amorphous wire 300 are isolated by the support layer 1100. The physical diagram of the amorphous wire sensor 10 is shown in Figure 15 As shown.

[0198] In summary, the amorphous wire sensor 10 of the present application overcomes the shortcomings of the conventional amorphous wire 300 GMI magnetic sensor, such as low production efficiency, poor device consistency, large volume, etc., and realizes electrical connection of the amorphous wire 300 and preparation of the three-dimensional coil based on the MEMS technology using the electroplating process. The support layer 1100 formed by the support material containing the non-photosensitive polyimide enhances the stability of the coil, optimizes the structure and preparation process of the three-dimensional coil, reduces the production cost and process complexity, reduces the volume of the amorphous wire sensor under the premise of ensuring the consistency of the device, improves the production efficiency of the sensor, and achieves the purpose of mass production of the miniature amorphous wire sensor.

[0199] In the above embodiments, the description of each embodiment focuses on different aspects, and the parts not described in detail in a certain embodiment can be referred to the related description of other embodiments.

[0200] The technical features of the above-described embodiments can be combined arbitrarily, and in order to make the description concise, not all possible combinations of the technical features in the above-described embodiments are described, however, as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the present application.

[0201] The above-described embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A method for preparing an amorphous wire sensor, characterized by, The method comprises the following steps: preparing a first metal seed layer, a bottom coil and a first metal sub-pad which are connected in layers on a substrate surface, fixing an amorphous wire on the bottom coil and arranging two ends of the amorphous wire on the first metal sub-pad respectively; spinning photoresist on the amorphous wire and the bottom coil, and after drying, exposure and development, part of the amorphous wire fixed on the first metal sub-pad is exposed, and the outer glass of the exposed amorphous wire is removed; after removing the photoresist remaining on the amorphous wire and the bottom coil, spinning a support material containing non-photosensitive polyimide on the substrate surface, drying to obtain a cover layer, spinning photoresist on the surface of the cover layer, and after drying, exposure and development, a patterned second groove with a curved inner wall is obtained, which separates the cover layer into a support layer arranged on the bottom coil and wrapping the amorphous wire and a wrapping layer arranged on the substrate and wrapping the bottom coil; after removing the photoresist remaining on the support layer and the wrapping layer, baking the support layer and the wrapping layer in an oxygen-free environment to imidize them; preparing a second metal seed layer on the surface of the support layer and the wrapping layer, spinning photoresist on the second metal seed layer, drying, exposing and developing part of the photoresist on the support layer and the second groove adjacent to the support layer to expose part of the second metal seed layer, and electroplating to prepare a second metal sub-pad on the exposed second metal seed layer at the end, and arranging the end of the amorphous wire between the first metal sub-pad and the second metal sub-pad, and preparing an arcuate coil on the non-exposed second metal seed layer, which extends along the surface of the support layer in a curved shape and covers the amorphous wire, and removing the photoresist and etching to remove the exposed second metal seed layer.

2. The production method according to claim 1, characterized by, When the first metal seed layer, the bottom coil and the first metal sub-pad which are connected in layers are prepared on the substrate surface in sequence, the following steps are included: preparing the first metal seed layer on the substrate surface; spinning photoresist on the surface of the first metal seed layer, and after drying, exposure and development, a patterned first groove is obtained; electroplating to prepare the bottom coil and the first metal sub-pad in the patterned first groove; after removing the remaining photoresist, etching to remove the exposed first metal seed layer.

3. The preparation method according to claim 2, characterized in that, The preparation method also satisfies at least one of the following conditions: (1) before preparing the first metal seed layer on the substrate, the following steps are included: cleaning the substrate with acetone, isopropyl alcohol and pure water in sequence, and then drying; (2) the preparation material of the first metal seed layer is Cr and / or Cu; (3) the preparation method of the first metal seed layer includes a magnetron sputtering process, wherein the magnetron sputtering power is 600W-700W, and the sputtering rate is 4.22 Å / s-6.59 Å / s; (4) the thickness of the first metal seed layer is 600 Å-2000 Å; (5) In the process of electroplating the bottom coil and the first metal sub-pad in the patterned first groove, the electroplating solution is CuSO4 solution, the electroplating current is 0.243A-0.3A, and the electroplating time is 480s-660s.

4. The preparation method according to claim 1, characterized in that, The preparation method further satisfies at least one of the following conditions: (1) The outer layer glass of the exposed amorphous wire is removed using HF solution, wherein the concentration of the HF solution is 3%-5%, and the etching time of the HF solution is 30min-35min; (2) The thickness of the spin-on support material is 40μm-60μm; (3) In the process of high-temperature baking the support layer in an oxygen-free environment, the baking temperature is increased from 60℃ to 350℃, and the baking time is 9h-15h; (4) The thickness of the second metal seed layer is 600Å-2000Å.

5. The preparation method according to claim 1, characterized in that, The preparation method further satisfies at least one of the following conditions: (1) The second metal seed layer is prepared on the surface of the imidized support layer by a magnetron sputtering process, wherein the magnetron sputtering power is 600W-700W, and the sputtering rate is 4.22 Å / s-6.59Å / s; (2) In the process of electroplating the second metal sub-pad and the arch-shaped coil on the exposed end of the second metal seed layer, the electroplating solution is CuSO4 solution, the electroplating current is 0.243A-0.3A, and the electroplating time is 480s-660s.

6. The method of any one of claims 1, 3, 5, wherein, The preparation method further satisfies at least one of the following conditions: (1) The thickness of the spin-on photoresist is 8μm-12μm; (2) The baking temperature for drying the photoresist is 100℃-120℃, and the baking time is 180s-300s; (3) In the process of exposing the photoresist, a hard contact exposure is adopted, and the exposure dose is 300mJ-600mJ; (4) In the process of developing the photoresist, the developing solution is an alkaline solution containing TMAH, and the developing time is 3min-6min.

7. The method of any one of claims 1, 3, 5, wherein, In the process of removing the photoresist remaining on the amorphous wire and the bottom coil, the photoresist remaining on the surface of the first metal seed layer, and the photoresist remaining on the support layer, the remaining photoresist is soaked in acetone, and then cleaned with isopropyl alcohol and pure water, wherein the soaking time of the acetone is 10min-20min. In the process of removing the photoresist remaining on the support layer, the remaining photoresist is soaked in propylene glycol monomethyl ether acetate solution and then cleaned with pure water.

8. An amorphous wire sensor prepared by the production method according to any one of claims 1 to 7, characterized by, The amorphous wire sensor comprises a substrate and a bottom coil, an amorphous wire, an arch coil, a metal pad, an amorphous wire signal lead and a coil signal lead connected to the substrate; the bottom coil is connected to the substrate, the metal pad is arranged on the bottom coil, the amorphous wire extends along the bottom coil and the amorphous wire end is electrically connected by wrapping the metal pad on the bottom coil, the arch coil is curved and covers the amorphous wire, the two ends of the arch coil are curved and inclined and extend to the bottom coil, the two ends of the arch coil are respectively connected to the bottom coil, the arch coil and the bottom coil have a support layer formed by curing a support material, the arch coil and the amorphous wire are isolated by part of the support layer, the height of the support layer from the bottom coil is greater than the diameter of the amorphous wire, the amorphous wire signal lead is electrically connected to the metal pad, and the coil signal lead is electrically connected to the arch coil.

9. The amorphous wire sensor of claim 8, wherein, The amorphous wire sensor further comprises a wrapping layer connected to the substrate and wrapping part of the bottom coil, part of the amorphous wire and part of the arch coil, wherein the metal pad wrapping the amorphous wire end, the top surface of the arch coil, the amorphous wire signal lead and the coil signal lead are exposed to the wrapping layer.

10. The amorphous wire sensor of claim 9, wherein, The wrapping layer is formed by a support material containing non-photosensitive polyimide.

11. The amorphous wire sensor according to any one of claims 8 to 10, wherein The top surface of the arch coil is parallel to the substrate, and the two side portions of the top surface are respectively arc-shaped curved, the width of the top surface of the arch coil is greater than the diameter of the amorphous wire. The height of the support layer from the bottom coil is 40-60 μm.

12. The amorphous wire sensor according to any one of claims 8 to 10, wherein The line of the bottom coil and the extension direction of the amorphous wire have an included angle in the horizontal plane ranging from 45° to 60°. The bottom coil extends in a strip shape on the substrate as a whole. The substrate is a glass substrate.

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