Linear zinc oxide ceramic resistor, method for manufacturing the same, and circuit board

Abstract

The application belongs to the technical field of ceramic resistance, and particularly relates to a linear zinc oxide ceramic resistance, a preparation method thereof and a circuit board. The linear zinc oxide ceramic resistance is prepared by applying a direct current voltage in a preparation process, so that a crystal boundary barrier formed in a sintering process is destroyed, the product, the zinc oxide ceramic resistance, has good linear characteristics, and thus the linear zinc oxide ceramic resistance is prepared, thereby solving the technical problem that a process for preparing the zinc oxide linear ceramic resistance is relatively complex in the prior art.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of ceramic resistors, and particularly relates to a linear zinc oxide ceramic resistor, a preparation method thereof and a circuit board. BACKGROUND

[0002] With the rapid development of the power electronics industry, higher requirements are provided for the miniaturization and economy of equipment. There is an urgent need for a linear resistor with a small resistivity variation range and a large current density to replace the previous resistor device. Compared with traditional resistor devices, the zinc oxide linear ceramic resistor has a high heat capacity and can absorb 800 J / cm 3 of energy in an instant, has super power, a volume of about 15% of the volume of a metal resistor with the same power, strong instantaneous current flow capacity, can withstand a high temperature of 500 DEG C, has the advantages of small volume and light weight, and is suitable for the development of modern power industry.

[0003] It is generally believed at present that a doping formula is a key factor for preparing the zinc oxide linear ceramic resistor. For example, doping La2O3 and ZrO2 and the like alkaline earth metals and oxides of the third and fourth groups of saturated metals can prepare the zinc oxide linear resistor by adjusting the grain boundary phase. The zinc oxide linear resistor can also be prepared by adjusting the grain boundary phase through the sintering temperature, holding time, heating rate and cooling rate in the preparation process. However, the doping amount of the doping metals such as La2O3 and ZrO2 is difficult to control in the process of preparing the zinc oxide linear ceramic resistor by doping formula. The sintering temperature required for preparing the linear resistor is too high, generally between 1300 DEG C and 1600 DEG C, which requires a higher sintering furnace and consumes a large amount of energy. Therefore, the process for preparing the zinc oxide linear ceramic resistor in the prior art is relatively complex. SUMMARY

[0004] Therefore, the application provides a linear zinc oxide ceramic resistor, a preparation method thereof and a circuit board, to solve the technical problem that the process for preparing the zinc oxide linear ceramic resistor in the prior art is relatively complex.

[0005] The first aspect of the application provides a preparation method of a linear zinc oxide ceramic resistor, and the preparation method comprises the following steps:

[0006] In step S1, a zinc oxide ceramic formula is sequentially subjected to mixing, ball milling, drying, granulation, tabletting and glue removal to prepare a zinc oxide ceramic green body.

[0007] In step S2, a high-temperature resistant conductive paste is coated on the surfaces of the two end faces of the zinc oxide ceramic green body, and the high-temperature resistant conductive paste is solidified at high temperature to obtain a zinc oxide ceramic resistor green body.

[0008] In step S3, the zinc oxide ceramic resistor green body is heated to a sintering temperature for sintering to obtain a linear zinc oxide ceramic resistor green body.

[0009] Step S4, a direct current bias is applied in the process of cooling the linear zinc oxide ceramic resistor green body, to obtain the linear zinc oxide ceramic resistor.

[0010] Preferably, in step S1, the zinc oxide ceramic formula includes 93.42 moles of ZnO, 1.2 moles of Bi2O3, 1 mole of Sb2O3, 1.1 moles of Co2O3, 0.5 moles of MnCO3, 1.3 moles of Ni2O3, and 1.48 moles of SiO2.

[0011] Preferably, in step S2, the high-temperature resistant conductive paste is silver paste or platinum paste.

[0012] Preferably, in step S2, the high-temperature curing temperature is 450-850℃, and the time is 20-40 min. Preferably, in step S2, the high-temperature curing temperature is 850℃, and the time is 30 min.

[0013] Preferably, in step S3, the heating rate is 2-3.33 min / ℃.

[0014] The sintering temperature is 800-1300℃, and the sintering time is 1-3 h.

[0015] Preferably, in step S3, the heating rate is 3.33 min / ℃.

[0016] The sintering temperature is 1080℃, and the sintering time is 2 h.

[0017] Preferably, in step S4, the direct current bias is not less than 5V / mm.

[0018] Preferably, in step S4, the direct current bias is 5-20V / mm.

[0019] The second aspect of the application provides a linear zinc oxide ceramic resistor prepared by the above preparation method.

[0020] The third aspect of the application provides a circuit board, including a substrate and electronic components.

[0021] The electronic components are arranged on the surface of the substrate.

[0022] The electronic components include the above linear zinc oxide ceramic resistor.

[0023] Preferably, the substrate is a copper-clad plate.

[0024] In summary, the application provides a linear zinc oxide ceramic resistor, a preparation method thereof and a circuit board. The preparation method of the linear zinc oxide ceramic resistor comprises the following steps: firstly, preparing a zinc oxide ceramic green body by sequentially mixing, ball milling, drying, granulating, tabletting and degassing a zinc oxide ceramic formula; then, solidifying high-temperature-resistant conductive paste on both end surfaces of the zinc oxide ceramic green body; and finally, sintering the zinc oxide ceramic resistor green body by heating to a sintering temperature

[0025] In summary, the application provides a linear zinc oxide ceramic resistor, a preparation method thereof and a circuit board. The preparation method of the linear zinc oxide ceramic resistor comprises the following steps: firstly, preparing a zinc oxide ceramic green body by sequentially mixing, ball milling, drying, granulating, tabletting and degassing a zinc oxide ceramic formula; then, solidifying high-temperature-resistant conductive paste on both end surfaces of the zinc oxide ceramic green body; and finally, sintering the zinc oxide ceramic resistor green body by heating to a sintering temperature BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the description of the embodiments or the prior art will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0027] Figure 1 A zinc oxide ceramic resistor J-E characteristic curve diagram provided for Embodiment 2 of the present application;

[0028] Figure 2 A schematic diagram of the grain boundary barrier and internal defect structure of the zinc oxide varistor ceramic in Embodiment 2 of the present application. DETAILED DESCRIPTION

[0029] The present application provides a linear zinc oxide ceramic resistor, a preparation method thereof and a circuit board, which are used to solve the technical problem that the process of preparing a zinc oxide linear ceramic resistor in the prior art is relatively complex.

[0030] The technical solutions of the present application will be described in detail below with reference to the drawings. Obviously, the described embodiments are some embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0031] Embodiment 1

[0032] Embodiment 1 of this application provides a method for preparing a linear zinc oxide ceramic resistor. The preparation method includes the steps of preparing a zinc oxide ceramic green body, preparing a zinc oxide ceramic resistor green body, preparing a linear zinc oxide ceramic resistor green body, and preparing a linear zinc oxide ceramic resistor.

[0033] The preparation steps of the zinc oxide ceramic green body include: using a typical zinc oxide varistor ceramic resistor.

[0034] The commercial formulation is: 93.42 mol% ZnO, 1.2 mol% Bi2O3, 1 mol% Sb2O3, 1.1 mol% Co2O3, 0.5 mol% MnCO3, 1.3 mol% Ni2O3, and 1.48 mol% SiO2. After batching, mixing, ball milling, drying, granulation, pressing, and debinding, a batch of zinc oxide green samples were obtained. The green samples were selected and recorded as zinc oxide ceramic green samples.

[0035] The preparation steps of the zinc oxide ceramic resistance green body include: coating the two end faces of two samples with high-temperature conductive platinum paste and curing at 850°C for half an hour to obtain the zinc oxide ceramic resistance green body;

[0036] The preparation steps of the linear zinc oxide ceramic resistor include: placing platinum electrode sheets on both end faces of the zinc oxide ceramic resistor green body, placing it in the high-temperature cavity of the high-temperature dielectric equipment, the heating rate of the zinc oxide ceramic resistor green body during sintering is 3.33℃ / min, the maximum sintering temperature is 1080℃, the sintering time is 2 hours, a DC electric field of 5V / mm is applied during the furnace cooling process, and the green body is cooled to room temperature to obtain the linear zinc oxide ceramic resistor.

[0037] Example 2

[0038] Example 2 of this application provides a method for preparing a zinc oxide ceramic resistor. As a comparative example of the preparation method described in Example 1, the preparation method includes a zinc oxide ceramic green body preparation step, a first zinc oxide ceramic resistor green body preparation step, and a zinc oxide ceramic resistor preparation step.

[0039] The preparation steps of the zinc oxide ceramic green body include: using a typical zinc oxide varistor ceramic resistor.

[0040] The commercial formulation is: 93.42 mol% ZnO, 1.2 mol% Bi2O3, 1 mol% Sb2O3, 1.1 mol% Co2O3, 0.5 mol% MnCO3, 1.3 mol% Ni2O3, and 1.48 mol% SiO2. After batching, mixing, ball milling, drying, granulation, pressing, and debinding, a batch of zinc oxide green samples were obtained. The green samples were selected and recorded as zinc oxide ceramic green samples.

[0041] The preparation steps of the first zinc oxide ceramic resistor green body include: coating high-temperature conductive platinum paste on two end faces of two samples, and curing at 850 DEG C for half an hour to obtain the first zinc oxide ceramic resistor green body;

[0042] The preparation steps of the zinc oxide ceramic resistor include: placing platinum electrode sheets on the two end faces of the first zinc oxide ceramic resistor green body, and placing the zinc oxide ceramic resistor green body into a high-temperature cavity of a high-temperature dielectric device, the heating rate of the sintering process of the zinc oxide ceramic resistor green body is 3.33 DEG C / min, the highest sintering temperature is 1080 DEG C, the sintering time is 2 hours, and then the zinc oxide ceramic resistor green body is directly cooled to room temperature with the furnace to obtain the zinc oxide ceramic resistor.

[0043] Embodiment 3

[0044] The embodiment 3 of the present application provides a circuit board, the circuit board comprises a substrate and electronic components, the electronic components are arranged on the surface of the substrate, and the electronic components comprise the linear zinc oxide ceramic resistor prepared by the preparation method in the embodiment 1.

[0045] Since the resistance in the electronic component of the circuit board provided in the embodiment is the linear zinc oxide ceramic resistor, the circuit board has the properties of high temperature resistance, large current density and light weight, and can meet the needs of modern power equipment.

[0046] The substrate can be selected from a copper-clad plate, a ceramic substrate and the like.

[0047] Experimental example 1

[0048] The experimental example 1 of the present application is used to test the performance of the linear zinc oxide ceramic resistor provided in the embodiment 1 and the zinc oxide ceramic resistor provided in the embodiment 2, and the performance test comprises the following steps: first polishing the two end faces of the linear zinc oxide ceramic resistor provided in the embodiment 1 and the zinc oxide ceramic resistor provided in the embodiment 2 with sandpaper, then cleaning the linear zinc oxide ceramic resistor and the zinc oxide ceramic resistor in alcohol in an ultrasonic wave, drying, spraying gold electrodes on the two end faces of the linear zinc oxide ceramic resistor and the zinc oxide ceramic resistor, and testing the J-E characteristic curve.

[0049] The zinc oxide ceramic resistor provided in the embodiment 2 has a nonlinear characteristic, and a nonlinear coefficient (a = 1 / lg(U1mA / U0.1mA)) is about 46.3, while the linear zinc oxide ceramic resistor provided in the embodiment 1 does not have a nonlinear characteristic, which indicates that the positive charged depletion layer defect ions are neutralized with the negative charged interface state charges at the grain boundary after the application of the direct current electric field of 5V / mm in the cooling process, can interfere with the arrangement of the intrinsic point defects and electrons at the grain boundary, destroy the formation of the good grain boundary barrier in the sintering process, so that the product zinc oxide ceramic resistor has a good linear characteristic, thereby the linear zinc oxide ceramic resistor is prepared; and the preparation method of the linear zinc oxide ceramic resistor provided in the application breaks the limitation of the doping formula, whether Bi2O3, La2O3 and ZrO2 are contained in the zinc oxide ceramic resistor formula does not affect the preparation of the linear zinc oxide ceramic resistor, at the same time, the sintering temperature is 1080℃, which is lower than the conventional sintering temperature of 1300℃-1600℃, therefore, compared with the prior art, the preparation method of the linear zinc oxide ceramic resistor provided in the application is simple.

[0050] The above embodiments are only used to illustrate the technical solutions of the application, rather than limit them; although the application is described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions recorded in the above embodiments can be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the application.

Claims

1. A method for producing a linear zinc oxide ceramic resistor, characterized by, The preparation method comprises the steps of: S1, preparing a zinc oxide ceramic green body by sequentially mixing, ball milling, drying, granulating, tabletting and degassing a zinc oxide ceramic formula; S2, coating the high-temperature resistant conductive paste on the surface of the two end faces of the zinc oxide ceramic green body, and high-temperature curing the high-temperature resistant conductive paste to obtain a zinc oxide ceramic resistor green body, wherein the temperature of the high-temperature curing is 450-850 ℃, and the time is 20-40 min; S3, sintering the zinc oxide ceramic resistor green body by heating it to a sintering temperature to obtain a linear zinc oxide ceramic resistor green body; S4, applying a direct current bias during the cooling process of the linear zinc oxide ceramic resistor green body to obtain a linear zinc oxide ceramic resistor, wherein the direct current bias is 5-20 V / mm.

2. The method of claim 1, wherein the linear zinc oxide ceramic resistor is prepared by the steps of: In step S1, the zinc oxide ceramic formula comprises, in terms of molar parts: 93.42 molar parts of ZnO, 1.2 molar parts of Bi2O3, 1 molar part of Sb2O3, 1.1 molar parts of Co2O3, 0.5 molar parts of MnCO3, 1.3 molar parts of Ni2O3, and 1.48 molar parts of SiO2. ​ 3. The method for preparing a linear zinc oxide ceramic resistor according to claim 1, characterized in that, In step S2, the high-temperature resistant conductive paste is silver paste or platinum paste.

4. The method for preparing a linear zinc oxide ceramic resistor according to claim 1, characterized in that, In step S3, the heating rate is 2-3.33 min / ℃, the sintering temperature is 800-1300 ℃, and the sintering time is 1-3 h.

5. A linear zinc oxide ceramic resistor, characterized by, Prepared by the preparation method of any one of claims 1-4.

6. A circuit board, characterized by It comprises a substrate and electronic components; the electronic components are arranged on the surface of the substrate; the electronic components comprise the linear zinc oxide ceramic resistor prepared by the preparation method of any one of claims 1-4.

7. A circuit board according to claim 6, wherein The substrate is a copper-clad plate.

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