Liquid metal resistor with wide resistance value range and preparation method thereof

Abstract

The invention provides a liquid metal resistor with a wide resistance value range and a preparation method thereof, the liquid metal resistor is prepared by adopting an ultrasonic jet printing technology, the preparation method specifically comprises the following steps: S1, taking liquid metal as a raw material, and carrying out atomization treatment to obtain liquid metal droplets; and S2, the air pressure of an ultrasonic spray head and the distance between the ultrasonic spray head and a substrate are adjusted, a printing network is constructed, the liquid metal liquid drops prepared in the step S1 serve as raw materials, and the liquid metal resistor is obtained through printing on the substrate. Compared with the prior art, the limitation of a traditional resistor in the aspects of resistance value adjusting range, precision and flexible circuit adaptability is solved.

Description

Technical Field

[0001] The present invention relates to the intersection of electronic technology and material science, and in particular to the innovation of resistor device manufacturing technology. Specifically, it relates to a liquid metal resistor with a wide resistance range and a preparation method thereof. Background Art

[0002] In the field of electronic technology, resistors, as one of the basic electronic components, play an important role in regulating current, dividing voltage, limiting current, etc. With the continuous miniaturization, lightness and intelligence of electronic products, higher requirements are placed on the performance of resistors, especially in terms of resistance adjustment range, accuracy and adaptability.

[0003] Traditional resistors are mostly made of solid materials, such as carbon film resistors, metal film resistors, etc. Although these resistors have stable resistance values ​​and good temperature stability, they have certain limitations in the resistance adjustment range, making it difficult to achieve a wide range of resistance adjustment. At the same time, the accuracy of traditional resistors is also limited by factors such as materials and processes, making it difficult to meet the needs of high-precision circuits.

[0004] In addition, with the rapid development of flexible electronic technology, higher requirements are placed on the flexibility of resistors. Due to the limitations of materials and structures, traditional solid-state resistors are difficult to adapt to the bending and deformation of flexible circuits, which easily leads to performance degradation or breakage. Therefore, developing a resistor with a wide resistance range, high precision and adaptability to flexible circuits has become a hot topic in current technical research.

[0005] With the rapid development of electronic technology, higher requirements are placed on the miniaturization, lightweight and flexibility of electronic components. Traditional resistors based on solid materials have limitations in resistance adjustment, integration and adaptability, and it is difficult to meet the special needs of flexible circuits. Liquid metal has become a research hotspot in the field of flexible electronics due to its excellent conductivity, plasticity and processability at low temperatures. However, how to efficiently and accurately control the resistance of liquid metal to form resistors in order to achieve wide-range, high-performance resistor preparation is the key to current technological breakthroughs. Summary of the invention

[0006] The present invention provides a liquid metal resistor with a wide resistance range and a preparation method thereof, aiming to solve the limitations of traditional resistors in terms of resistance adjustment range, precision and adaptability to flexible circuits. The method combines ultrasonic printing technology, external air pressure regulation and atomization time control, realizes high-precision preparation of a wide range of resistance values ​​from low to high, and is particularly suitable for flexible circuits, providing a new technical means for the development of flexible electronic products.

[0007] The first object of the present invention is to provide a method for preparing a liquid metal resistor with a wide resistance range, the preparation method specifically comprising the following steps:

[0008] S1, using liquid metal as raw material, obtaining liquid metal droplets through atomization treatment;

[0009] S2, adjusting the air pressure of the ultrasonic nozzle, the distance between the ultrasonic nozzle and the substrate, and constructing a printing network, using the liquid metal droplets obtained in step S1 as a raw material, and printing on the substrate to obtain a liquid metal resistor.

[0010] In some embodiments, in step S1, the parameters of the atomization treatment are as follows: the frequency of the generator is 1-200 kHz, the power is 1-100 W; the flow rate of the injection pump is 0.01-20 ml / s; and the time of the atomization treatment is 0.001-5 h.

[0011] Compared with the prior art, the present invention adopts a specific frequency and amplitude to uniformly atomize the liquid metal into tiny particles. This step ensures the uniformity and consistency of the particles, and provides a basis for the precise control of the resistance value; at the same time, the atomization time of the liquid metal is controlled by a precise time setting device. The extension or shortening of the atomization time will directly affect the size, distribution and fusion state of the particles, thereby achieving fine-tuning of the resistance value. Specifically: the extension of the atomization time will lead to an increase in the particle size and a diffusion of the distribution, while the shortening of the atomization time will lead to a decrease in the particle size and a concentration of the distribution. Fine-tuning of the resistance value is achieved by precisely controlling the atomization time.

[0012] In some embodiments, in step S2, the air pressure is 0.001-1.0 MPa.

[0013] Compared with the prior art, the present invention regulates the fusion degree of atomized particles by precisely adjusting the applied air pressure. The increase or decrease of air pressure will directly affect the contact and fusion state between particles, thereby achieving a preliminary adjustment of the resistance value. Specifically, when the air pressure increases, the fusion degree between particles increases and the resistance value decreases; when the air pressure decreases, the fusion degree between particles decreases and the resistance value increases.

[0014] In some embodiments, in step S2, the diameter of the liquid metal droplet used as the raw material is 10-15 μm and the width is 2-80 μm.

[0015] In some embodiments, the distance between the ultrasonic nozzle and the substrate is 0.1-30 cm.

[0016] In some embodiments, the construction of the printing network includes setting a printing path and a network density, the printing path is a single layer or a multi-layer superposition, and the network density includes a density distribution of particles.

[0017] Compared with the existing technology, a three-dimensional network structure of liquid metal particles is constructed by multi-layer superposition or specific path printing. This structure not only enhances the mechanical stability of the resistor, but also achieves a large adjustment of the resistance value by adjusting the network density and complexity; an increase in network density will lead to a decrease in resistance value, while a decrease in network density will lead to an increase in resistance value.

[0018] In some embodiments, the liquid metal is a gallium-based liquid metal, and the gallium-based liquid metal includes a gallium main body, and the gallium main body is selected from one of pure gallium, gallium-indium alloy, and gallium-indium-tin alloy.

[0019] In some embodiments, the gallium-based liquid metal also includes a balance component, and the balance component is selected from one or more of iron-based monometallic materials, cobalt-based monometallic materials, nickel-based monometallic materials, copper-based monometallic materials, silver-based monometallic materials, multinary magnetic metals, multinary non-magnetic metals, and solid non-metallic materials.

[0020] In some embodiments, the substrate is selected from one of a rigid substrate, a flexible substrate, and an elastic substrate.

[0021] In some embodiments, the hard substrate is selected from one of wood, PCB, FR4, polytetrafluoroethylene, and silicon wafer.

[0022] In some embodiments, the flexible substrate is selected from one of a cloth-based material, a paper-based material, a PI film, a plastic film, a PET film, and PVA.

[0023] In some embodiments, the elastic substrate is selected from one of PDMS, silicone, Ecoflex, SBS elastomer, POE elastomer, aliphatic aromatic random copolyester, rubber, resin, hydrogel, polyurethane, styrene block copolymer, PVC, polyimide, polyethylene terephthalate plastic, polyethylene octene co-elastomer, and thermoplastic elastomer.

[0024] The second object of the present invention is to provide a liquid metal resistor with a wide resistance range, which is prepared by the above preparation method, and the resistance of the liquid metal resistor with a wide resistance range is 10 6 ~10 -2 Ω.

[0025] Compared with the prior art, the present invention has the following advantages:

[0026] The prepared liquid metal resistor has excellent flexibility and mechanical strength, and can be directly deposited on a flexible substrate without the need for additional connectors or welding processes. This feature simplifies circuit construction, reduces production costs and environmental impact, and improves circuit reliability and service life. The raw materials are easily available, the preparation cost is low, it is green and environmentally friendly, and the utilization rate is high, which makes it easy to promote the large-scale preparation of liquid metal circuits. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a process schematic diagram of the preparation method of the present invention;

[0028] Figure 2 The actual pictures of the liquid metal resistors prepared in Examples 1 to 4 of the present invention;

[0029] Figure 3 A graph showing the tensile stability test results of the liquid metal resistor prepared in Example 1 of the present invention;

[0030] Figure 4 It is the principle diagram of applying air pressure of the present invention. DETAILED DESCRIPTION

[0031] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below. It should be noted that the following embodiments are only used to illustrate the implementation method and typical parameters of the present invention, and are not used to limit the parameter range described in the present invention. Reasonable changes derived therefrom are still within the scope of protection of the claims of the present invention.

[0032] It should be noted that the endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed in this article.

[0033] Unless otherwise defined, all terms, symbols and other scientific terms used herein are intended to have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. In some cases, terms with conventionally understood meanings are defined herein for the purpose of clarification or ease of reference, and such definitions herein should not be construed as indicating significant differences from conventional understandings in the art. The technical methods described or cited herein are generally well understood by those skilled in the art and are adopted by conventional methods. Unless otherwise stated, the use of commercially available kits, reagents and instruments is carried out in accordance with the protocols and parameters given by the manufacturer.

[0034] It is worth mentioning that, in the present invention, the relationship between resistance (R) and ultrasonic frequency (f), power (P), liquid inlet speed (v), atomization time (t) and substrate height (h) can be expressed by the following formula:

[0035] R=R0·[1+k1·(ff0) α +k2·(PP0) β]·[1+k3·(v0v) γ ]·[1+k4·(t0t)δ]·[1+k5·(hh0)∈]

[0036] In this formula:

[0037] R0 is the intrinsic resistivity of the material, which represents the resistance without any external influence.

[0038] f0, P0, v0, t0, h0 are reference or standard values ​​used to normalize the various parameters. These values ​​can be selected based on experimental conditions or material properties.

[0039] k1, k2, k3, k4, k5 are coefficients related to specific experimental conditions and material properties. They describe the degree of influence of each parameter on the resistance when it changes relative to the reference value.

[0040] α, β, γ, δ, ∈ are exponents that describe how the effect of each parameter on the resistance changes as the parameter value changes. The values ​​of these exponents can be positive or negative, depending on how the parameter affects the resistance.

[0041] The structure of this formula allows us to consider the effect of each parameter on the resistance separately, and these effects are measured by comparing it to a reference value. The effect of each parameter is represented by a multiplier (i.e. the expression in brackets), and when this multiplier is equal to 1, it means that the parameter value is equal to the reference value, at which time the parameter has no effect on the resistance. When the parameter value deviates from the reference value, the multiplier will change, resulting in a change in resistance.

[0042] The following combination Figure 1 The technical effects of the present invention are described with specific embodiments.

[0043] Example 1

[0044] This embodiment provides a liquid metal resistor with a resistance value of 10 kΩ ± 5%, which is prepared by the following preparation method using ultrasonic printing technology:

[0045] S1. Gallium-indium alloy (EGaIn) is used as liquid metal material. The liquid metal material is placed in an ultrasonic printing device. The liquid metal is uniformly atomized into tiny particles through ultrasonic vibration. The diameter of the liquid metal particles is controlled between 40-80μm and the width is between 20-40μm to ensure the uniformity and consistency of the particles. The parameters of the atomization treatment are as follows: the frequency of the generator is 120kHz and the power is 15W; the flow rate of the injection pump is 0.01ml / s; the atomization treatment time is 0.003h; at the same time, during the atomization process, the external air pressure value is 0.01MPa, and the degree of fusion of the atomized particles is regulated by accurately adjusting the air pressure value.

[0046] S2. Set the height between the ultrasonic nozzle and the substrate to 5 cm, adopt a multi-layer superposition method, and construct a printing network by adjusting the number of printing layers and the distribution density of particles in each layer. Use the liquid metal droplets obtained in step S1 as raw material to print on the substrate to obtain a liquid metal resistor with a resistance value of 10kΩ±5%.

[0047] Example 2

[0048] This embodiment provides a liquid metal resistor with a resistance value of 1 kΩ±5%, which is prepared by the following preparation method using ultrasonic printing technology:

[0049] S1. Gallium-indium alloy (EGaIn) is used as liquid metal material. The liquid metal material is placed in an ultrasonic printing device. The liquid metal is uniformly atomized into tiny particles through ultrasonic vibration. The diameter of the liquid metal particles is controlled between 40-80μm and the width is between 20-40μm to ensure the uniformity and consistency of the particles. The parameters of the atomization treatment are as follows: the frequency of the generator is 120kHz and the power is 15W; the flow rate of the injection pump is 0.01ml / s; the atomization treatment time is 0.003h; at the same time, during the atomization process, the external air pressure value is 0.01MPa, and the degree of fusion of the atomized particles is regulated by accurately adjusting the air pressure value.

[0050] S2. Set the height between the ultrasonic nozzle and the substrate to 3 cm, adopt a multi-layer superposition method, and construct a printing network by adjusting the number of printing layers and the distribution density of particles in each layer. Use the liquid metal droplets obtained in step S1 as raw material to print on the substrate to obtain a liquid metal resistor with a resistance value of 1kΩ±5%.

[0051] Example 3

[0052] This embodiment provides a liquid metal resistor with a resistance value of 100Ω±5%, which is prepared by the following preparation method using ultrasonic printing technology:

[0053] S1. Gallium-indium alloy (EGaIn) is used as liquid metal material. The liquid metal material is placed in an ultrasonic printing device. The liquid metal is uniformly atomized into tiny particles through ultrasonic vibration. The diameter of the liquid metal particles is controlled between 40-80μm and the width is between 20-40μm to ensure the uniformity and consistency of the particles. The parameters of the atomization treatment are as follows: the frequency of the generator is 120kHz and the power is 15W; the flow rate of the injection pump is 0.01ml / s; the atomization treatment time is 0.002h; at the same time, during the atomization process, the external air pressure value is 0.08MPa, and the degree of fusion of the atomized particles is regulated by accurately adjusting the air pressure value.

[0054] S2. Set the height between the ultrasonic nozzle and the substrate to 3 cm, adopt a multi-layer superposition method, and construct a printing network by adjusting the number of printing layers and the distribution density of particles in each layer. Use the liquid metal droplets obtained in step S1 as raw material to print on the substrate to obtain a liquid metal resistor with a resistance value of 100Ω±5%.

[0055] Example 4

[0056] This embodiment provides a liquid metal resistor with a resistance value of 1Ω±5%, which is prepared by the following preparation method using ultrasonic printing technology:

[0057] S1. Gallium-indium alloy (EGaIn) is used as liquid metal material. The liquid metal material is placed in an ultrasonic printing device. The liquid metal is uniformly atomized into tiny particles through the vibration of ultrasonic waves. The diameter of the liquid metal particles is controlled between 40-80μm and the width is between 20-40μm to ensure the uniformity and consistency of the particles. The parameters of the atomization treatment are as follows: the frequency of the generator is 120kHz and the power is 15W; the flow rate of the injection pump is 0.01ml / s; the atomization treatment time is 0.002h; at the same time, during the atomization process, the external air pressure value is 0.1MPa, and the degree of fusion of the atomized particles is regulated by accurately adjusting the air pressure value.

[0058] S2. Set the height between the ultrasonic nozzle and the substrate to 3 cm, adopt a multi-layer superposition method, and construct a printing network by adjusting the number of printing layers and the distribution density of particles in each layer. Use the liquid metal droplets obtained in step S1 as raw material to print on the substrate to obtain a liquid metal resistor with a resistance value of 1Ω±5%.

[0059] The actual pictures of the liquid metal resistors prepared in Examples 1-4 are as follows: Figure 2 shown.

[0060] The inventors further conducted a tensile stability test on the liquid metal resistor with a resistance value of 10 kΩ ± 5% obtained in Example 1. The test results are as follows: Figure 3 As shown, from Figure 3 It can be seen that the prepared liquid metal resistor has high tensile stability.

[0061] Example 5

[0062] This embodiment provides a liquid metal resistor, which is different from Embodiment 1 only in that, during the preparation process of this embodiment, no external gas pressure is applied during the atomization process. It is found through testing that the resistance value of the liquid metal resistor prepared in this embodiment can also reach 10kΩ±5%, but correspondingly, the preparation time is increased to 0.005h.

[0063] Its principle is as follows Figure 4As shown in the figure, when the air pressure increases, the degree of fusion between particles increases and the resistance value decreases; when the air pressure decreases, the degree of fusion between particles decreases and the resistance value increases. From the above results, it can be seen that the present invention combines ultrasonic printing technology, distance control from the substrate, external air pressure control and printing time control to achieve high-precision preparation of a wide range of resistance values ​​from low to high.

[0064] Example 6

[0065] This embodiment provides a liquid metal resistor, which is different from Embodiment 1 only in that, during the preparation process of this embodiment, during the atomization treatment, the atomization time is 0.004h. After testing, it can be found that the resistance value of the liquid metal resistor prepared in this embodiment is 6kΩ.

[0066] It can be seen from the results of Example 1 and Example 6 that the atomization time of the liquid metal is controlled by a precise time setting device. The extension or shortening of the atomization time will directly affect the size, distribution and fusion state of the particles, thereby achieving fine-tuning of the resistance value.

[0067] Example 7

[0068] This embodiment provides a liquid metal resistor, which is different from Embodiment 1 only in that the liquid metal resistor of this embodiment is a single-layer printing method. After testing, it can be found that the resistance value of the liquid metal resistor prepared in this embodiment is 400 kΩ.

[0069] It can be seen from the results of comparative example 7 and example 1 that the flexibility of ultrasonic printing is utilized to construct a three-dimensional network structure of liquid metal particles through multi-layer superposition or specific path printing. This structure not only enhances the mechanical stability of the resistor, but also achieves a substantial adjustment of the resistance value by adjusting the network density and complexity.

[0070] Although the disclosure is disclosed as above, the protection scope of the disclosure is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the disclosure, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. A method for preparing a liquid metal resistor with a wide resistance range, characterized in that: The liquid metal resistor is prepared by ultrasonic printing technology, and the preparation method specifically comprises the following steps: S1, using liquid metal as raw material, obtaining liquid metal droplets through atomization treatment; S2, adjusting the air pressure of the ultrasonic nozzle, the distance between the ultrasonic nozzle and the substrate, and constructing a printing network, using the liquid metal droplets obtained in step S1 as a raw material, and printing on the substrate to obtain a liquid metal resistor.

2. The preparation method according to claim 1, characterized in that In step S1, the parameters of the atomization treatment are as follows: the frequency of the generator is 1-200 kHz, the power is 1-100 W; the flow rate of the injection pump is 0.01-20 ml / s; and the time of the atomization treatment is 0.1-5 h.

3. The preparation method according to claim 1, characterized in that: In step S2, the air pressure is 0.001-1.0 MPa.

4. The preparation method according to claim 1, characterized in that: In the step S2, the diameter of the liquid metal droplet as the raw material is 10-15 μm and the width is 2-80 μm.

5. The preparation method according to claim 1, characterized in that: In the step S2, the distance between the ultrasonic nozzle and the substrate is 0.1-30 cm.

6. The preparation method according to claim 1, characterized in that: In the step S2, the construction of the printing network includes setting a printing path and a network density, the printing path is a single layer or a multi-layer superposition, and the network density includes a density distribution of particles.

7. The preparation method according to claim 1, characterized in that: In the step S2, the substrate is selected from one of a hard substrate, a flexible substrate and an elastic substrate.

8. The preparation method according to claim 7, characterized in that: The hard substrate is selected from one of wood, PCB, FR4, polytetrafluoroethylene, and silicon wafer; And / or, the flexible substrate is selected from one of a cloth-based material, a paper-based material, a PI film, a plastic film, a PET film, and PVA; And / or, the elastic substrate is selected from one of PDMS, silicone, Ecoflex, SBS elastomer, POE elastomer, aliphatic aromatic random copolyester, rubber, resin, hydrogel, polyurethane, styrene block copolymer, PVC, polyimide, polyterephthalate plastic, polyethylene octene co-elastomer, and thermoplastic elastomer.

9. The preparation method according to claim 1, characterized in that: The liquid metal is a gallium-based liquid metal, the gallium-based liquid metal includes a gallium main body, and the gallium main body is selected from one of pure gallium, gallium-indium alloy, and gallium-indium-tin alloy; And / or, the gallium-based liquid metal also includes a balance component, and the balance component is selected from one or more of iron-based monometallic materials, cobalt-based monometallic materials, nickel-based monometallic materials, copper-based monometallic materials, silver-based monometallic materials, multi-component magnetic metals, multi-component non-magnetic metals and solid non-metallic materials.

10. A liquid metal resistor with a wide resistance range, prepared by the preparation method according to any one of claims 1 to 9, characterized in that: The resistance of the liquid metal resistor with a wide resistance range is 10 6 ~10 -2 Ω.

Images