Stable chip resistor and preparation method thereof

Abstract

According to the stable chip resistor and the preparation method thereof provided by the invention, a plurality of protective layer structures are adopted, the stability and reliability of the resistor are ensured, the structure and performance of the resistor are optimized, the overall process flow is beneficial to improving the durability and adaptability of a product, especially the performance in severe application environments such as automotive electronics, and the production cost is reduced. A progressive increase structure formed by two times of printing enables the manufacturing process to be more controllable, the consistency and quality of products can be improved, and the defect rate in production is reduced; according to the stable chip resistor, the first protection layer is arranged in a crossing mode to completely cover the resistance layer, the influence of the external environment on the resistance layer is effectively isolated, resistance fluctuation caused by temperature and humidity changes is reduced, the second protection layer is of an incremental structure formed through two times of printing, the thickness of the protection layer is increased, and the stability of the stable chip resistor is improved. And the overall impact resistance and wear resistance of the resistor are improved, the performance stability of the resistor is enhanced, and the service life of the resistor is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of resistors, and in particular to a stable chip resistor and a preparation method thereof. Background Art

[0002] Chip resistors are mainly used in the automotive industry. In the domestic market, existing resistor products are difficult to meet performance test standards and need to be improved in quality. In particular, the instability of the resistance value of existing chip resistors may cause abnormal current and voltage, generate excessive heat, affect other related electronic components, and seriously affect driving safety. In addition, frequent changes in resistance value will shorten the service life of the entire electronic component and increase the cost of maintenance and replacement. In view of this, the stability requirements for chip resistors are becoming more and more stringent. Summary of the invention

[0003] In view of this, the object of the present invention is to provide a stable chip resistor and a preparation method thereof to solve the above-mentioned problems.

[0004] The present invention adopts the following scheme:

[0005] The present application provides a stable chip resistor, comprising a substrate, a pair of back electrodes, a pair of front electrodes, a resistance layer, a protective layer and side electrodes; the resistance layer covers between the front electrodes, the protective layer covers on the resistance layer, and the side electrodes are respectively arranged on opposite sides of the substrate for electrode connection between the front electrode and the back electrode on the corresponding side; the protective layer comprises a first protective layer and a second protective layer; the first protective layer is placed between the two front electrodes to completely cover the resistance layer, the second protective layer covers on the first protective layer, and the second protective layer is printed twice to form at least two protective layer structures with increasing sizes.

[0006] As a further improvement, the thickness of each protective layer is relatively uniform to reduce the slope between the protective layer and the front electrode.

[0007] As a further improvement, the first protective layer is made of glass material, and the second protective layer is made of at least two layers of epoxy resin material.

[0008] As a further improvement, the protective layer of the glass material has a thickness of 15um; the protective layer of the first layer of epoxy resin material has a thickness of less than 15um, and the protective layer of the second layer of epoxy resin material has a thickness of more than 15um.

[0009] As a further improvement, a third protective layer is formed correspondingly on the uncovered front electrode, and the third protective layer is made of resin silver material.

[0010] As a further improvement, the uncovered area is smaller than the covered area to increase the overlapping area between the resistance layer and the front electrode.

[0011] As a further improvement, the third protection layer is arranged to intersect with the side electrode.

[0012] As a further improvement, the resistor layer is cut by ultraviolet laser to form a laser cutting groove that is inwardly contracted relative to the fold line, thereby performing laser resistance adjustment.

[0013] As a further improvement, one protective layer structure is printed by a 250-mesh screen, and another protective layer structure is printed by a 325-mesh screen.

[0014] As a further improvement, the size of the first protective layer is increased to 0.65 mm*1.17 mm.

[0015] The present application further provides a method for preparing a stable chip resistor, comprising the following steps:

[0016] S1: providing a substrate, forming back electrodes separated from each other on the lower surface of the substrate, and forming front electrodes separated from each other on the upper surface of the substrate;

[0017] S2: forming a resistance layer connected to the front electrode;

[0018] S3: forming a first protective layer on the resistance layer, which is arranged between the front electrodes to completely cover the resistance layer;

[0019] S4: forming at least two second protective layers of the protective layer structure with increasing sizes on the first protective layer by printing twice;

[0020] S5: forming a third protective layer corresponding to the uncovered front electrode;

[0021] S6: Sputtering is performed along the side to form a side electrode connecting the front electrode and the back electrode on the corresponding side.

[0022] As a further improvement, in step S2, it further includes:

[0023] The resistor layer is cut by ultraviolet laser to form a laser cutting groove that is inwardly contracted relative to the fold line, thereby performing laser resistance adjustment.

[0024] As a further improvement, the parameters of the purple laser are: wavelength 400nm, resistance 1MΩ, power 4W, speed 80mm / s, pulse 220p / mm, so as to cut a crack-free L-shaped laser cutting groove.

[0025] As a further improvement, in step S4, it further includes:

[0026] One protective layer structure is printed by a 250-mesh screen, and another protective layer structure is printed by a 325-mesh screen.

[0027] As a further improvement, the thickness of each protective layer is relatively uniform to reduce the slope between the protective layer and the front electrode.

[0028] As a further improvement, in step S5, it further includes:

[0029] Resin silver material is used as the third protective layer, and the third protective layer is subjected to hydrophobic treatment.

[0030] As a further improvement, the semi-finished product of the printed resin silver material is transported to the drying furnace along a preset distance, with a transmission speed of 250 mm / min, a leveling time of 4.4 min, and a sintering temperature of 220°C.

[0031] By adopting the above technical solution, the present invention can achieve the following technical effects:

[0032] 1. The stable chip resistor of the present application completely covers the resistor layer by spanning the first protective layer, effectively isolating the influence of the external environment on the resistor layer and reducing the resistance fluctuation caused by temperature and humidity changes. In particular, the incremental structure of the second protective layer formed by two printings not only increases the thickness of the protective layer, but also improves the overall impact resistance and wear resistance of the resistor, and also enhances the performance stability of the resistor and extends its service life.

[0033] 2. Through the preparation method of stable chip resistors, a multiple protective layer structure is adopted to ensure the stability and reliability of the resistor, aiming to optimize the structure and performance of the resistor, from the processing of the substrate to the formation of the resistor layer, to the printing of multiple protective layers and the sputtering of side electrodes. The overall process helps to improve the durability and adaptability of the product, especially in harsh application environments such as automotive electronics. The incremental structure formed by two printings makes the manufacturing process more controllable, which helps to improve the consistency and quality of the product and reduce the defect rate in production. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic structural diagram of a stable chip resistor according to an embodiment of the present invention;

[0035] Figure 2 yes Figure 1 A schematic diagram of the structure of the protective layer in FIG.

[0036] Figure 3 is a schematic diagram of a tangent line of a stable chip resistor according to an embodiment of the present invention under ultraviolet laser parameters;

[0037] Figure 4Schematic diagram of the grinding of the third protective layer of the stable chip resistor according to an embodiment of the present invention after hydrophobic treatment;

[0038] Figure 5 Schematic diagram of the hydrophobicity of the resistor layer after the hydrophobic treatment of the third protective layer of the stable chip resistor according to an embodiment of the present invention;

[0039] Figure 6 It is a structural block diagram of a method for preparing a stable chip resistor according to an embodiment of the present invention;

[0040] Figure 7 It is a flow chart of a method for preparing a stable chip resistor according to an embodiment of the present invention.

[0041] Icon: 1-substrate; 2-back electrode; 3-front electrode; 4-resistance layer; 5-first protective layer; 6-second protective layer; 7-third protective layer. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention.

[0043] Example

[0044] Combination Figures 1 to 5 This embodiment provides a stable chip resistor, including a substrate 1, a pair of back electrodes 2, a pair of front electrodes 3, a resistor layer 4, a protective layer and side electrodes (not shown).

[0045] The resistance layer 4 is covered between the front electrodes 3, the protection layer is covered on the resistance layer 4, and the side electrodes are respectively arranged on opposite sides of the substrate 1 for connecting the front electrodes 3 and the back electrodes 2 on the corresponding sides.

[0046] The protective layer includes a first protective layer 5 and a second protective layer 6. The first protective layer 5 is placed between the two front electrodes 3 to completely cover the resistance layer 4. The second protective layer 6 covers the first protective layer 5. The second protective layer 6 is printed twice to form at least two protective layer structures with increasing sizes.

[0047] The stable chip resistor mentioned above completely covers the resistance layer 4 by the first protective layer 5, effectively isolating the resistance layer 4 from the influence of the external environment and reducing the resistance fluctuation caused by temperature and humidity changes. In particular, the second protective layer 6 has an incremental structure formed by two printings, which not only increases the thickness of the protective layer, but also improves the overall impact resistance and wear resistance of the resistor, and also enhances the performance stability of the resistor and prolongs its service life.

[0048] In this embodiment, the thickness of each protective layer is relatively uniform, so as to reduce the slope between the protective layer and the front electrode 3, so that the step slope of the contact point between the protective layer and the front electrode is reduced after printing, thereby reducing the current concentration effect in this area and reducing the loss of electrical performance. In addition, reducing the slope helps the protective layer to be more evenly distributed during the printing process, avoiding printing defects caused by uneven thickness, thereby improving the overall quality.

[0049] Preferably, the first protective layer 5 is made of glass material, and the second protective layer 6 is made of at least two layers of epoxy resin material. Thus, the first protective layer 5 of glass material and the second protective layer 6 of epoxy resin material provide a multi-layer protective structure, which effectively prevents water vapor penetration and improves the stability and reliability of the resistor in a humid environment. The first protective layer 5 of glass material is not only moisture-proof, but also provides excellent mechanical protection, which can resist external impact and pressure, so that the resistor remains intact and stable under harsh conditions. The second protective layer 6 of epoxy resin material has good electrical insulation, which avoids the risk of failure of the resistor due to leakage or short circuit, ensures the stability of electrical performance, and the double-layer protective structure enables the resistor to resist the erosion of environmental factors for a long time, reduces the performance degradation caused by changes in the external environment, and thus greatly extends the service life of the product.

[0050] Furthermore, the protective layer of glass material has a thickness of 15um. The protective layer of the first epoxy resin material has a thickness less than 15um, and the protective layer of the second epoxy resin material has a thickness greater than 15um. Incrementally increasing the film size of the second protective layer 6 can further effectively solve the problem of incomplete graphics during printing.

[0051] In this embodiment, a third protective layer 7 is formed correspondingly on the uncovered front electrode 3, and the third protective layer 7 is composed of a resin silver material. The uncovered area is smaller than the covered area to increase the overlapping area between the resistor layer 4 and the front electrode 3. The third protective layer 7 is arranged to intersect with the side electrode to ensure a smooth transition between the electrode surface and the external electrical connection, reduce the poor contact problem caused by the height difference, and thus improve the electrical connection reliability of the resistor. The resin silver material has good electrical conductivity and protective properties. Applying it to the third protective layer 7 not only provides additional physical protection for the electrode, further resists the water vapor erosion of the electrode by the external environment, but also maintains the electrical conductivity of the electrode, effectively preventing the resistance change or failure caused by corrosion.

[0052] In this embodiment, the resistor layer 4 is cut by a violet laser to form a laser cutting groove that is retracted relative to the fold line, thereby performing laser resistance adjustment. On the one hand, the wavelength of violet light is shorter than that of red light. The shorter the wavelength, the higher the photon energy, and the stronger the focusing ability and the higher the energy density, so that the violet light can act on the material more accurately during cutting, reduce the scattering and diffusion of energy, thereby reducing the thermal impact on the surrounding materials, and further reducing the cracks generated at the tangent edge. On the other hand, the high energy density and precise focusing characteristics of violet light result in a smaller heat-affected zone during the cutting process. A smaller heat-affected zone means that the degree of thermal expansion and cooling contraction of the material is relatively small, reducing the generation of cracks caused by thermal stress. In addition, the high frequency characteristics of violet light enable it to complete the cutting process more quickly when interacting with the material, reducing the continuous heating time of the material during the cutting process, thereby reducing the generation of cracks.

[0053] In this embodiment, one protective layer structure is printed by a screen with a mesh number of 250, and another protective layer structure is printed by a screen with a mesh number of 325. Thus, two protective layer structures of different sizes and thicknesses are printed by screens with different mesh numbers. At the same time, the netting effect between the two is reduced.

[0054] In this embodiment, the size of the first protective layer 5 is increased to 0.65 mm*1.17 mm. In the prior art, the size of the first protective layer 5 is 0.55 mm*0.55 mm. Thus, the increase in the size of the first protective layer 5 allows the resistor layer 4 to be completely covered and extended to cover the front electrode 3, while allowing the resistor layer 4 and the protective layer to cover more of the electrode.

[0055] Second, combining Figure 6 and Figure 7 This embodiment further provides a method for preparing a stable chip resistor, comprising the following steps:

[0056] S1: providing a substrate 1, forming back electrodes 2 separated from each other on the lower surface of the substrate 1, and forming front electrodes 3 separated from each other on the upper surface of the substrate 1;

[0057] S2: forming a resistor layer 4 connected to the front electrode 3;

[0058] S3: forming a first protective layer 5 on the resistor layer 4 so as to straddle between the front electrodes 3 and completely cover the resistor layer 4;

[0059] S4: Forming at least two second protective layers 6 of the protective layer structure with increasing sizes on the first protective layer 5 by printing twice;

[0060] S5: forming a third protective layer 7 corresponding to the uncovered front electrode 3;

[0061] S6: Sputtering is performed along the side surface to form a side electrode connecting the front electrode 3 and the back electrode 2 on the corresponding side.

[0062] The use of multiple protective layer structures ensures the stability and reliability of the resistor, aiming to optimize the structure and performance of the resistor. From the processing of the substrate 1 to the formation of the resistor layer 4, to the printing of the multi-layer protective layer and the sputtering of the side electrodes, the overall process helps to improve the durability and adaptability of the product, especially in harsh application environments such as automotive electronics. The incremental structure formed by the two printings makes the manufacturing process more controllable, which helps to improve the consistency and quality of the product and reduce the defect rate in production.

[0063] In step S2, it also includes:

[0064] The resistor layer 4 is cut by ultraviolet laser to form a laser cutting groove that is inwardly contracted relative to the fold line, thereby performing laser resistance trimming.

[0065] Furthermore, the parameters of the violet laser are: wavelength 400nm, resistance 1MΩ, power 4W, speed 80mm / s, pulse 220p / mm, so as to cut a crack-free L-shaped laser cutting groove. Figure 3 As shown, by changing the color and wavelength of the laser light during cutting, the final inspection shows that there is no crack on the edge of the cut line.

[0066] In step S4, it also includes:

[0067] One protective layer structure is printed by a 250-mesh screen, and another protective layer structure is printed by a 325-mesh screen.

[0068] Preferably, the thickness of each protective layer is relatively uniform, so as to reduce the slope between the protective layer and the front electrode 3 .

[0069] In step S5, it also includes:

[0070] Resin silver material is used as the third protective layer 7, and the third protective layer 7 is subjected to hydrophobic treatment. Among them, the hydrophobic treatment can make the surface of the resin layer less likely to absorb moisture, effectively prevent the intrusion of water vapor, reduce the resistance value change and performance degradation caused by water vapor, and improve the stability and reliability of the resistor working in a humid environment. In a complex and changeable use environment, the chip resistor that has been hydrophobicized can better resist the influence of adverse external factors, reduce the probability of failure, and ensure normal operation and service life.

[0071] Furthermore, the semi-finished product of the printed resin silver material is transported to the drying furnace along a preset distance, with a transmission speed of 250 mm / min, a leveling time of 4.4 min, and a sintering temperature of 220°C. After this process, Figure 4 As shown in Figure 1, the polished appearance of the third protective layer is obviously free of bubbles. Figure 5 As shown, the resistor is particularly hydrophobic.

[0072] The above are only preferred implementations of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention.

Claims

1. A method for preparing a stable chip resistor, characterized in that: The steps include: S1: providing a substrate, forming back electrodes separated from each other on the lower surface of the substrate, and forming front electrodes separated from each other on the upper surface of the substrate; S2: forming a resistance layer connected to the front electrode; S3: forming a first protective layer on the resistance layer, which is arranged between the front electrodes to completely cover the resistance layer; S4: forming at least two second protective layers of the protective layer structure with increasing sizes on the first protective layer by printing twice; S5: forming a third protective layer corresponding to the uncovered front electrode; S6: Sputtering is performed along the side to form a side electrode connecting the front electrode and the back electrode on the corresponding side.

2. The method for preparing a stable chip resistor according to claim 1, characterized in that: In step S2, it also includes: The resistor layer is cut by ultraviolet laser to form a laser cutting groove that is inwardly contracted relative to the fold line, thereby performing laser resistance adjustment.

3. The method for preparing a stable chip resistor according to claim 2, characterized in that: The parameters of the violet laser are: wavelength 400nm, resistance 1MΩ, power 4W, speed 80mm / s, pulse 220p / mm, so as to cut a crack-free L-shaped laser cutting groove.

4. The method for preparing a stable chip resistor according to claim 1, characterized in that: In step S4, it also includes: One protective layer structure is printed by a 250-mesh screen, and another protective layer structure is printed by a 325-mesh screen.

5. The method for preparing a stable chip resistor according to claim 4, characterized in that: The thickness of each protective layer is relatively uniform, so as to reduce the slope between the protective layer and the front electrode.

6. The method for preparing a stable chip resistor according to claim 1, characterized in that: In step S5, it also includes: Resin silver material is used as the third protective layer, and the third protective layer is subjected to hydrophobic treatment.

7. The method for preparing a stable chip resistor according to claim 6, characterized in that: The semi-finished product of printed resin silver material is transported to the drying furnace along a preset distance, with a transmission speed of 250 mm / min, a leveling time of 4.4 min, and a sintering temperature of 220°C.

8. The method for preparing a stable chip resistor according to claim 6, characterized in that: The third protection layer is arranged to intersect with the side electrode.

9. The method for preparing a stable chip resistor according to claim 1, characterized in that: The first protective layer is composed of glass material, and the second protective layer is composed of at least two layers of epoxy resin material; wherein the protective layer of the glass material has a thickness of 15um; the protective layer of the first layer of epoxy resin material has a thickness less than 15um, and the protective layer of the second layer of epoxy resin material has a thickness greater than 15um.

10. A stable chip resistor, characterized in that: Produced based on the preparation method according to any one of claims 1 to 9.

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