阅读说明：本技术 一体化柔性微纳电感及其制备方法 (Integrated flexible micro-nano inductor and preparation method thereof ) 是由 王军强 张文武 张岩 曹小文 向明亮 许巍 霍军涛 于 2021-09-23 设计创作，主要内容包括：本发明公开了一种一体化柔性微纳电感及其制备方法,涉及基于激光刻蚀方法的非晶纳米晶微纳电感器件的制备。制备方法包括：制备非晶纳米晶合金；基于高精度高功率激光刻蚀加工方法,按照应用场景、形状及尺寸的需求,对所述非晶纳米晶合金进行与磁芯结构直接结合的一体化激光精细刻蚀加工,制备得到微纳尺度的一体化柔性电感器件。(The invention discloses an integrated flexible micro-nano inductor and a preparation method thereof, and relates to the preparation of an amorphous nanocrystalline micro-nano inductor device based on a laser etching method. The preparation method comprises the following steps: preparing amorphous nanocrystalline alloy; based on a high-precision high-power laser etching processing method, according to the requirements of application scenes, shapes and sizes, integrated laser fine etching processing of the amorphous nanocrystalline alloy directly combined with a magnetic core structure is carried out, and the micro-nano integrated flexible inductance device is prepared.)

1. A preparation method of an integrated flexible micro-nano inductor is characterized by comprising the following steps:

preparing amorphous nanocrystalline alloy;

based on a high-precision high-power laser etching processing method, according to the requirements of application scenes, shapes and sizes, integrated laser fine etching processing of the amorphous nanocrystalline alloy directly combined with a magnetic core structure is carried out, and the micro-nano integrated flexible inductance device is prepared.

2. The method according to claim 1, wherein the amorphous nanocrystalline alloy comprises a bulk, ribbon, wire, or powder.

3. The preparation method according to claim 1, comprising the steps of:

1) preparing an amorphous nanocrystalline alloy and magnetic core structure, and outputting a blank to be processed;

2) according to the geometric information of the inductance device, a CAM code of laser processing is generated;

3) controlling laser to perform fine processing forming on the blank workpiece;

4) packaging;

5) and (5) checking the machine type.

4. The manufacturing method according to claim 1, wherein the high-precision high-power laser etching processing method comprises:

the single pulse energy is 80 muJ at the maximum,

a laser with a wavelength of 515fs, a laser with a wavelength of 532ps,

the pulse is a pulse of 400fs and,

pulse laser peak power 3.82 x 10¹³W/cm²，

The laser line width is more than 2 mu m.

5. The preparation method according to claim 1 or 4, wherein the micro-nano integrated flexible inductor is in a strip shape, the microstructure of the strip is an amorphous or nanocrystalline structure, the thickness of the strip is 15-40 μm, and the width of the strip is 1-170 mm.

6. The integrated flexible inductance device with the micro-nano scale prepared by the preparation method according to any one of claims 1 to 5.

Technical Field

The invention relates to the technical field of inductor preparation, in particular to an integrated flexible micro-nano inductor and a preparation method thereof.

Background

The third generation semiconductor material is developed rapidly, the 5G/5G + mobile phone, base station, satellite communication field and electric vehicle industry are developed rapidly, electronic components such as inductors with low loss, high frequency and high power density are developed and prepared according to the requirements of the manufacture of high-performance integrated circuits, flexible circuit boards and flexible devices and the working environment, and meanwhile, higher requirements are provided for the size, shape, integration, flexibility and integral formability of the devices.

Amorphous alloys are metastable materials of disordered structure that are obtained by rapid solidification of a metal melt. The amorphous ferromagnetic soft magnetic alloy has high saturation magnetic induction intensity, and has soft magnetic performance of very high magnetic conductivity and low coercive force due to the absence of magnetocrystalline anisotropy caused by a crystal structure; in addition, the amorphous alloy has the advantages of high yield strength, high hardness, ultrahigh elastic limit, good flexibility and strong corrosion resistance. The nanocrystalline soft magnetic alloy has more excellent soft magnetic performance (high magnetic conductivity and low coercive force, and extremely low iron loss) and higher saturation magnetic induction intensity due to the soft magnetic coupling effect of amorphous and nanocrystalline grains.

At present, for the preparation and processing of traditional inductors and other tiny devices, the most similar implementation schemes of the invention mainly comprise the following schemes: the method comprises the steps of preparing a magnetic powder core micro device based on powder press forming, preparing a film, preparing based on modes such as chemical etching and the like, processing based on materials such as silicon steel and the like, electron beam and plasma beam etching methods, physical cutting methods such as knife engraving and the like, and processing methods such as wire cutting and the like.

Preparing a magnetic powder core micro device based on powder press molding: the preparation of the high-power density output magnetic powder core requires the compression molding of high-sphericity micro powder with high saturation magnetic induction intensity by cold pressing, hot pressing and other modes. The preparation process comprises the steps of magnetic powder preparation, magnetic powder surface passivation treatment, binder insulation coating, granulation, compression molding, coil implantation, solidification, heat treatment, processing, packaging and the like, and the cost of micro-processing and time is higher; the performance of the device is easy to be unstable due to multi-step production and processing process flows; in addition, the device prepared by the process does not have the performances of high strength, high elasticity and the like.

Preparing an inductor by using a thin film: the preparation methods of magnetron sputtering, spraying and the like have great difficulty for preparing devices with complex shapes, the control condition of uniformity is rigorous, and the processing precision and stripping at the later stage have difficulty.

Preparation based on chemical etching and other modes: chemical etching is difficult to realize the preparation of tiny magnetic devices with high complexity, and the etching effect on the surface of the tiny magnetic devices is easy to change the magnetic performance of the magnetic devices.

Processing based on silicon steel and other materials: the silicon steel material has high saturation magnetic induction intensity, and is beneficial to time high-power density output, but the silicon steel strip with micro-nano scale is difficult to obtain; the soft magnetic performance of the silicon steel material is lower than that of a high-performance amorphous nanocrystalline soft magnetic material, and the soft magnetic performance of the silicon steel material is further reduced through machining processes such as cutting, grinding and the like, so that the loss is increased; the silicon steel material with micro-nano size can also cause the reduction of soft magnetic performance because the grain size is reduced; the out-of-plane crystal phase orientation is also complicated, and the soft magnetic performance of the device in practical application is easily reduced; in addition, the device prepared by the method has the performance of high strength, high elasticity and the like.

The electron beam and plasma beam etching method comprises the following steps: the electron beam and plasma beam etching processing needs to be carried out in a vacuum environment, batch preparation is not easy to realize, the processing time is long, and the preparation and processing process cost and the time cost are very high.

Mechanical cutting method such as knife carving: the processing precision is low, and the micro-nano size device is difficult to prepare; the processing time is long, and the mass operation is difficult to realize; processing of amorphous nanocrystalline materials of high strength and hardness is more difficult.

The processing methods such as wire cutting and the like comprise: the processing time is longer, and the time cost is high; it is easy to cause local atomic structural rearrangement of the material, resulting in reduction of magnetic properties.

Disclosure of Invention

Aiming at the defects in the field, the invention provides a preparation method of an integrated flexible micro-nano inductor, and relates to the preparation of an amorphous nanocrystalline micro-nano inductor based on a laser etching method.

A preparation method of an integrated flexible micro-nano inductor comprises the following steps:

preparing amorphous nanocrystalline alloy;

based on a high-precision high-power laser etching processing method, according to the requirements of application scenes, shapes and sizes, integrated laser fine etching processing of the amorphous nanocrystalline alloy directly combined with a magnetic core structure is carried out, and the micro-nano integrated flexible inductance device is prepared.

The amorphous nanocrystalline alloy comprises blocks, strips, filaments, powder and the like.

The invention solves the technical problem that the amorphous nanocrystalline soft magnetic material with high power density output characteristic is difficult to obtain the preparation of the flexible variable micro-nano scale inductance device by the traditional processing means.

The material used by the invention has good soft magnetic performance with high saturation magnetic induction and low loss, and the laser etching processing is carried out in situ, so that the high-precision processing at the micro-nano level can be realized, the difficult problems of devices with micro size, complex structure and appearance can be solved, and the miniaturization of the devices under the high-power-density output high-frequency working environment can be realized.

The preparation of the flexible inductance device is based on a laser etching method, can realize assembly line high-batch processing operation, has less process flow and short period, can save a large amount of time and processing cost, has high efficiency, and can improve the consistency and stability of the device.

The application substrate combined with the inductance device can realize good integrated forming/integration, and has good integration and high integration degree with a circuit board and an integrated circuit.

In a preferred embodiment, the method for preparing the integrated flexible micro-nano inductor specifically comprises the following steps:

1) preparing an amorphous nanocrystalline alloy and magnetic core structure, and outputting a blank to be processed;

2) according to the geometric information of the inductance device, a CAM code of laser processing is generated;

3) controlling laser to perform fine processing forming on the blank workpiece;

4) packaging;

5) and (5) checking the machine type.

In a preferred embodiment, the high-precision high-power laser etching processing method includes:

the single pulse energy is 80 muJ at the maximum,

a laser with a wavelength of 515fs, a laser with a wavelength of 532ps,

the pulse is a pulse of 400fs and,

pulse laser peak power 3.82 x 10¹³W/cm²，

The laser line width is more than 2 mu m.

In a preferred example, the micro-nano scale integrated flexible inductor is in a strip shape, the microstructure of the strip is an amorphous or nanocrystalline structure, the thickness of the strip is 15-40 μm, and the width of the strip is 1-170 mm.

The invention also provides a micro-nano scale integrated flexible inductance device prepared by the preparation method.

The amorphous nanocrystalline magnetically soft alloy has good mechanical strength and elastic performance, and is beneficial to realizing the preparation of flexible electronic devices such as flexible inductors and the like; the amorphous nanocrystalline magnetically soft alloy has high saturation magnetic induction intensity, can be used for preparing electronic devices with high power density output, and is beneficial to the miniaturization of the devices and the realization of high integration level in application environments.

The solidified amorphous and nanocrystalline alloy can be prepared into the shapes of blocks, strips, wires, powder and the like, has simple preparation process, stable magnetic performance and high uniformity of the alloy, and can be produced in batches; based on the laser etching mode, the method has the advantages of high precision, high resolution and short processing period, is favorable for realizing batch production, and can reduce the preparation cost and time cost.

Amorphous and nanocrystalline alloys are processed based on a laser etching mode, so that in-situ integrated molding can be realized; the processing precision is high, the resolution ratio is high, and the preparation of a micro device with a high complex appearance can be realized.

Bulk silicon steel materials with high saturation magnetic induction are easy to obtain, but are difficult to prepare in strip, wire and powder forms, the processing cost is high, and micro-nano-scale devices are difficult to obtain even based on the same laser etching technology. In addition, the grain size of the oriented silicon steel is usually millimeter level, the grain size of the non-oriented silicon steel is generally larger than 50 μm, and the soft magnetic performance is deteriorated due to the reduction of the grain size in the preparation of the silicon steel material with micro-nano size. Therefore, materials such as silicon steel with soft magnetic performance based on large crystal grain size control are not suitable for preparing micro devices with micro-nano sizes.

Based on methods such as electron beam and plasma beam etching, materials need to be etched in a vacuum environment, the processing time is long, the method is difficult to be suitable for batch preparation and production, and the laser etching technology is difficult to replace in processing and time cost.

At present, magnetic powder particles with good sphericity, excellent soft magnetic performance and high saturation magnetic induction intensity are basically larger than 10 microns, and micro-nano scale is difficult to realize during the process of pressing and forming magnetic powder cores.

The preparation and processing of high-precision micro-nano devices are difficult to realize by chemical etching and knife etching.

The processing time is long in a linear cutting mode and the like, the time cost is high, and the method is suitable for processing a single device; moreover, the local atomic structure of the material is easily rearranged during the processing process, which results in the reduction of the magnetic performance.

In conclusion, the scheme of the invention is difficult to replace by other schemes.

Compared with the prior art, the invention has the main advantages that:

1. the amorphous nanocrystalline soft magnetic material on the magnetic core structure is integrally and precisely processed, and the miniaturized manufacture of high-energy density inductors on complex three-dimensional structures is realized.

2. The strip material is processed by a pulse width laser of 400fs, precise etching forming can be realized, and the peak power density of the pulse laser is 3.82 multiplied by 10¹³W/cm²So as to avoid the change of the texture caused by the influence of heat on the stripThe original properties of the material are maintained.

3. According to the method, the amorphous nanocrystalline soft magnetic material with high mechanical strength and high elasticity can be etched into electronic devices such as ultra-high performance flexible inductors and the like.

4. The amorphous nanocrystalline magnetically soft alloy has high saturation magnetic induction intensity and high power density output characteristic, and the prepared micro-nano device can realize miniaturization and high integration level in environments such as large-scale integrated circuits.

5. The solidified amorphous and nanocrystalline alloy can be prepared into the shapes of blocks, strips, wires, powder and the like, and has simple preparation process, stable magnetic performance and high uniformity.

6. Based on the laser etching mode, the method has the advantages of high precision and short processing period, is favorable for realizing batch production, and can reduce the preparation cost and time cost.

7. The laser etching method has high processing precision and high resolution, utilizes instantaneous local sublimation processing, does not change the intrinsic magnetic characteristics of the material while forming in a 3D complex manner, and is easy to obtain a micro device with a complex shape and ultrahigh turn density.

Drawings

FIG. 1 is a schematic diagram of a process for preparing an amorphous nanocrystalline alloy laser etching micro-nano inductance device;

fig. 2 is an inductance value diagram of the micro inductor with different line widths according to the embodiment.

Detailed Description

The invention is further described with reference to the following drawings and specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The following examples are conducted under conditions not specified, usually according to conventional conditions, or according to conditions recommended by the manufacturer.

Interpretation of terms:

(1) an inductor, also called an inductor, refers to an element that can convert electrical energy into magnetic energy and store the magnetic energy, and the inductor blocks the change of current. The inductor may be classified into an iron core coil, a ferrite coil, a copper core coil, and an air core coil, which are made by winding a conductive material around a magnetic core. The inductor device provided by the invention is obtained by in-situ laser etching of amorphous nanocrystalline magnetically soft alloy.

(2) The magnetic powder core is generally formed by coating a high-resistivity substance on the surface of metal-based magnetic powder and then pressing the metal-based magnetic powder core in a powder metallurgy mode according to the shape requirement. The preparation method enables the magnetic powder core to have a unique structure of insulation among magnetic particles, can effectively block the eddy current effect among the magnetic particles under a high-frequency working condition, not only solves the problems of low resistivity and high loss of the soft magnetic material, but also retains the good intrinsic soft magnetic characteristics of the metal soft magnetic material, such as high magnetic conductivity and high saturation magnetization.

(3) The saturation magnetization refers to the maximum magnetization that can be achieved when a magnetic material is magnetized in an external magnetic field, and is called saturation magnetization. Conditions are provided for realizing miniaturization of electronic components. The saturation magnetization directly influences the power output capability of the device/magnetic core body, is the core performance of the power device, and provides conditions for realizing the miniaturization of electronic components. For the magnetic powder core material, under the condition of the same main body magnetic powder, the higher the proportion of the main body soft magnetic powder participating in magnetization is, the higher the saturation magnetic induction intensity is.

(4) Permeability, which is a physical quantity characterizing the magnetism of a magnetic medium, is the ability of a magnetic core to be magnetized in a spatial magnetic field, and is equal to the ratio of the magnetic induction (B) to the magnetic field strength (H) in the magnetic medium, i.e., μ ═ B/H. The high permeability material can realize saturation magnetization only by a weak external magnetic field. The compressed density of the magnetic powder core, the kind and addition ratio of substances other than the bulk powder affect the effect of soft magnetic coupling between the magnetic powder particles. The magnetic permeability affects the magnetization efficiency of the power device/magnetic powder core.

(5) The coercive force means that the magnetic induction intensity B of the magnetic material does not return to zero when the external magnetic field returns to zero after saturation magnetization. It is necessary to add a magnetic field of a certain magnitude in the opposite direction of the original magnetization field to return the magnetic induction to zero, and the magnetic field is called coercive force. The same magnetic permeability parameter, the pressing density of the magnetic powder core, the types and the adding proportion of substances except the main powder influence the soft magnetic coupling effect among the magnetic powder particles, and the coercive force of the device/the magnetic powder core is improved by adding and increasing the non-magnetic substances and excessively small pressing density, so that the hysteresis loss is increased.

(6) The integration level, in order to meet the requirements of miniaturization and complication of integrated circuits/microcircuits in the fields of electric vehicles, 5G communication, chips and the like at present and in the future, adopts a certain process to interconnect elements such as transistors, resistors, capacitors, inductors and the like required in a circuit and wiring, improves the integration level of various elements and components, and forms a miniature structure with the required circuit function.

(7) The flexible electronic material has flexibility, flexibility and extensibility, has high conformality, transparency and portability, and has wide application prospect in the fields of information, energy, medical treatment, national defense and the like. In order to meet the requirements of complicated shapes, miniaturization and the like of integrated circuits/microcircuits and the like, electronic devices with flexibility have a very large research and development space.

(8) The basic principle of laser etching is to focus a high-quality low-power laser beam (generally, ultraviolet laser or fiber laser) into a very small spot and form a very high power density at the focus, so that the material is vaporized and evaporated instantly to form a hole, a slit or a groove. The processing technology comprises laser micro-nano cutting, scribing, etching, drilling and the like. The laser etching has the characteristics of excellent processing performances of non-contact processing, high flexibility, high processing speed, no noise, small heat affected zone, capability of focusing to a very small light spot at a laser wavelength level and the like of the laser, obtains good size precision and processing quality of drilling, scribing, etching and cutting, and is widely applied to processing of electronic semiconductor materials.

The preparation process of the amorphous nanocrystalline alloy laser etching micro-nano inductance device is shown in figure 1 and comprises the following steps:

preparing amorphous nanocrystalline alloy, including blocks, strips, wires and powder;

based on a high-precision high-power laser etching processing method, according to the requirements of application scenes, shapes and sizes, integrated laser fine etching processing of the amorphous nanocrystalline alloy directly combined with a magnetic core structure is carried out, and the micro-nano integrated flexible inductance device is prepared.

In this embodiment, taking a strip as an example, the specific parameter conditions of the high-precision high-power laser etching processing method are as follows:

the single pulse energy is 80 muJ at the maximum,

a laser with a wavelength of 515fs, a laser with a wavelength of 532ps,

the pulse is a pulse of 400fs and,

pulse laser peak power 3.82 x 10¹³W/cm²

The laser line width is more than 2 mu m.

The obtained micro-nano integrated flexible inductance device is in a strip shape, the microstructure of the strip is an amorphous structure, namely a nanocrystalline structure, the thickness of the strip is 15-40 mu m, and the width of the strip is 1-170 mm.

Specifically, the peak power used in this embodiment is 3.82 × 10¹³W/cm²The femtosecond pulse laser carries out laser etching on the surface of the strip, and micro-nano inductors with different diameters and turns are obtained. During the laser etching process, the laser frequency is kept in a low frequency range of several hundred hertz. The strip is an Fe-Si-B-Nb-Cu amorphous strip with the thickness of 18 mu m. And the micro inductors with the line widths of 0.3 mm, 0.15 mm and 0.1mm and the turns of 5mm, 10 mm and 15 mm are prepared by laser etching the amorphous strips. The inductance value of the micro inductor in this example was measured using an agilent 4294A precision impedance analyzer, and the result is shown in fig. 2.

A comparison of the miniature inductors of the present embodiment with some prior art inductance values is shown in table 1.

TABLE 1

Species of	Inductance value (nH)	Literature
			Embedded silicon inductor (PIiS)	430	*1
Electrochemical deposition micro-inductor for silicon substrate	440	*2
			Integrated toroidal inductor (5.6 mm)	500	*3
Hollow inductor embedded in PCB	220	*4
			MEMS micro-inductor (2.9 mm) on silicon substrate2)	204	*4
Miniature inductor example of the invention (15 turns; diameter 1.5mm)	1390

*1.DOI:10.1109/TPEL.2016.2588501

*2.DOI:10.1109/TMAG.2008.2001584

*3.DOI:10.1109/TMAG.2006.879571

*4.DOI:10.1016/j.jmmm.2020.167661

Furthermore, it should be understood that various changes and modifications can be made by one skilled in the art after reading the above description of the present invention, and equivalents also fall within the scope of the invention as defined by the appended claims.