Laminated resistor and manufacturing method thereof
Through laser ablation and printing electrode paste, the problem of existing NTC thermistors being difficult to miniaturize in smaller size applications is solved, and the manufacturing of smaller size and lower cost thermistors is achieved, which simplifies the production process and improves product performance.
Patent Information
- Application Number
- CN202411742211.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-29
- Publication Date
- 2025-03-11
AI Technical Summary
It is difficult to achieve miniaturization when used in smaller sizes of 0402, 0201 or 01005 because the accuracy of the end device is difficult to meet the design requirements and process is limited.
Laser ablation technology is used to open holes on the substrate and fill the electrode slurry. The end electrode and bottom electrode are formed by lamination pressing and cutting, and the traditional stain and sintering process is omitted, and the dense ceramic structure and L-shaped external electrode are formed directly through sintering and electroplating.
The manufacturing of smaller size NTC thermistors is realized, saving costs and production processes, simplifying processes, suitable for the production of smaller size products, and improving production efficiency and product performance.
Smart Images
Figure CN119601324A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to electronic components, and in particular to a multilayer resistor and a manufacturing method thereof. Background Art
[0002] With the explosion of demand for consumer electronics and automotive electronics, the application scenarios of temperature detection and temperature compensation have increased, and the demand for high-precision, high-reliability chip NTC thermistors has surged. The development trend of NTC thermistors is towards miniaturization and thinning. Currently, the mass-produced chip NTC thermistors in the industry are 0603 / 0402 sizes based on the stacking solution, and there are no 0201 or even smaller NTC thermistors.
[0003] The current solutions for chip NTC thermistors are as follows: Figure 1 As shown, it includes an inner lead electrode 1, a non-lead inner electrode 2, an end electrode 4, a bottom electrode 5 and a ceramic body 3; the internal structure is formed by printing and laminating, and after firing the ceramic, the end electrodes 4 are formed by dipping or dipping at both ends, followed by electroplating. This method is currently widely used in sizes above 0603, but it is difficult to achieve in smaller sizes such as 0402, 0201 or 01005, because the accuracy of the equipment used for dipping is difficult to meet the design requirements, and the product fixing process during dipping is also relatively limited, thus hindering the miniaturization of thermistors.
[0004] It should be noted that the information disclosed in the above background technology section is only used for understanding the background of the present application, and therefore may include information that does not constitute prior art known to ordinary technicians in the field. Summary of the invention
[0005] The main purpose of the present invention is to overcome the defects existing in the above-mentioned background technology and provide a multilayer resistor and a manufacturing method thereof.
[0006] To achieve the above object, the present invention adopts the following technical solutions:
[0007] A method for manufacturing a multilayer resistor comprises the following steps:
[0008] S1. Film layer: multiple film layers are made as substrates;
[0009] S2. Opening holes: Opening holes at positions corresponding to electrodes on the substrate by laser ablation to form holes for filling electrode slurry;
[0010] S3. Printing electrode slurry: printing electrode slurry on the substrate with holes, printing into an electrode pattern, and filling the holes;
[0011] S4. Lamination pressing: stacking multiple film layers together and applying pressure to make them tightly bonded to form a multi-layer structured rectangular resistor block prototype; wherein the electrode pattern in the middle of the film layer and the electrode pattern at the bottom of the film layer are bonded together through the electrode slurry in the holes;
[0012] S5. Cutting: vertically cutting the stacked rectangular resistor block along the hole position, so that the junction area between the electrode pattern in the middle of the film layer and the electrode pattern at the bottom of the film layer is exposed to form an end electrode, and the electrode pattern at the bottom of the film layer after cutting forms a bottom electrode connected to the end electrode;
[0013] S6. Sintering: Sintering the cut semi-finished product to form a dense ceramic structure;
[0014] S7. Electroplating: Electroplating the sintered porcelain body to obtain a finished product.
[0015] Further:
[0016] In step S1, a single square film layer with a thickness of 10 μm-100 μm is formed by a dry tape casting process.
[0017] The slurry used in the dry tape casting process is obtained by using a chemical coprecipitation method or a ball milling method to obtain a uniformly mixed composite oxide containing transition metals, and then a solvent and a plasticizer are added to the powder to prepare a slurry.
[0018] In step S3, the components of the electrode slurry include one or more of palladium, platinum, gold, copper, nickel, and silver.
[0019] In step S6, the cut semi-finished product is sintered at a high temperature of 1000-1300°C.
[0020] In step S7, nickel or copper is plated first, then tin is plated, and then cleaning and drying are performed to complete the electroplating.
[0021] The overlapping length between the lead-out internal electrode and the non-lead-out internal electrode formed by the electrode pattern in the middle of the film layer accounts for 1 / 3 to 2 / 3 of the length of the non-lead-out internal electrode.
[0022] The thickness of the terminal electrode at its narrowest point is between 5 μm and 20 μm, and the minimum interlayer spacing between the lead-out inner electrode and the non-lead-out inner electrode is 1.0 to 5.0 times the thickness of the terminal electrode at its narrowest point.
[0023] The multilayer resistor is an NTC thermistor.
[0024] A multilayer resistor comprises a ceramic substrate formed by stacking a plurality of film layers, the substrate being provided with an inner electrode, an end electrode and a bottom electrode, the inner electrode and the bottom electrode being both electrode patterns formed by printing, grooves extending perpendicular to the stacking direction being formed on the two end surfaces of the substrate respectively, the end electrode being formed by curing an electrode slurry filled in the groove, the end electrode being connected to the bottom electrode, and forming an L-shaped external electrode structure on the outer surface of the substrate.
[0025] The present invention has the following beneficial effects:
[0026] The present invention proposes a multilayer resistor and a manufacturing method thereof, which eliminates the dipping or impregnation process of the traditional NTC thermistor, and performs laser ablation on the electrode layer, performs openings on the substrate of the electrode layer, and then prints the electrode slurry, and fills the openings with the electrode slurry. The interlayer partial area is connected and conducted by lamination and pressurization. The cutting is performed at the opening position, so that a complete electrode appears on the cut surface. Then, sintering is performed to form an internal resistor structure while also forming an "L"-shaped external electrode, and then electroplating is performed to meet the mounting requirements. The present invention can effectively meet the market demand for smaller size and lower cost thermistors.
[0027] Compared with the conventional chip NTC thermistor, which forms the end surface electrode by dipping or dipping, the present invention has the following advantages:
[0028] First, it saves costs. Since this solution is an "L"-shaped terminal electrode, compared with the fully enclosed terminal electrode, the electrode slurry consumption is less, which saves more costs.
[0029] Second, the manufacturing process of the middle end of the product is simplified. The present invention omits the two major processes of dipping and burning the end of the traditional solution by adding a hole-opening process, thereby simplifying the product manufacturing process and accelerating the product manufacturing cycle.
[0030] Third, it is conducive to the production of small-sized products. Since the present invention does not require terminal dipping, the formation of terminal electrodes comes from a more precise opening printing process, thus avoiding the high-precision requirements of terminal dipping machines for 0402, 0201 (metric) or even smaller-sized terminal dipping.
[0031] Other beneficial effects of the embodiments of the present invention will be further described below. BRIEF DESCRIPTION OF THE DRAWINGS
[0032] Figure 1 It is a main cross-sectional structural diagram of an existing chip NTC thermistor.
[0033] Figure 2a It is a front cross-sectional structural diagram of a multilayer resistor according to an embodiment of the present invention.
[0034] Figure 2bIt is a left side view of the multilayer resistor according to an embodiment of the present invention.
[0035] Figure 2c FIG. 1 is a bottom view of a multilayer resistor according to an embodiment of the present invention.
[0036] Figure 3 It is a top view of the openings and electrode patterns in the layer where the lead-out internal electrodes are located and the layer where the non-lead-out internal electrodes are located according to an embodiment of the present invention.
[0037] Figure 4 FIG. 4 is a flow chart of a method for manufacturing a multilayer resistor according to an embodiment of the present invention. DETAILED DESCRIPTION
[0038] The following is a detailed description of the embodiments of the present invention. It should be emphasized that the following description is only exemplary and is not intended to limit the scope and application of the present invention.
[0039] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element. In addition, connection can be used for fixing as well as for coupling or communication.
[0040] It should be understood that the orientation or position relationship indicated by terms such as "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.
[0041] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.
[0042] See also Figures 2a to 4 The present invention provides a method for manufacturing a multilayer resistor, comprising the following steps:
[0043] S1. Film layer: multiple film layers are made as substrates;
[0044] S2. Opening holes: Opening holes at positions corresponding to electrodes on the substrate by laser ablation to form holes 6 for filling electrode slurry;
[0045] S3. Printing electrode paste: printing electrode paste on the substrate with holes, printing into electrode pattern 7, and filling the holes 6;
[0046] S4. Lamination pressing: stacking multiple film layers together and applying pressure to make them tightly bonded to form a prototype of a multilayer rectangular resistor block; wherein the electrode pattern in the middle of the film layer and the electrode pattern at the bottom of the film layer are bonded together through the electrode slurry of the hole 6;
[0047] S5. Cutting: vertically cut the stacked rectangular resistor block along the hole position, so that the junction area between the electrode pattern in the middle of the film layer and the electrode pattern at the bottom of the film layer is exposed to form an end electrode 4, and the electrode pattern at the bottom of the film layer after cutting forms a bottom electrode 5 connected to the end electrode 4; Figure 2a As shown, the electrode patterns in the stack form an internal resistor structure (such as the lead-out internal electrode 1 and the non-lead-out internal electrode 2), while the end electrode 4 and the bottom electrode 5 also form an "L"-shaped external electrode together;
[0048] S6. Sintering: Sintering the cut semi-finished product to form a dense ceramic body 3;
[0049] S7. Electroplating: Electroplating the sintered porcelain body to obtain a finished product.
[0050] In some embodiments, in step S1, a single square film layer with a thickness of 10 μm-100 μm is formed by a dry tape casting process.
[0051] In some embodiments, the slurry used in the dry tape casting process is obtained by using a chemical co-precipitation method or a ball milling method to obtain a uniformly mixed composite oxide containing transition metals, and then a solvent and a plasticizer are added to the powder to prepare a slurry.
[0052] In some embodiments, in step S3, the components of the electrode slurry include one or more of palladium, platinum, gold, copper, nickel, and silver.
[0053] In some embodiments, in step S6, the cut semi-finished product is sintered at a high temperature of 1000-1300°C.
[0054] In some embodiments, in step S7, nickel or copper is plated first, then tin is plated, and then cleaning and drying are performed to complete the electroplating.
[0055] In some embodiments, the overlapping length between the lead-out internal electrode 1 and the non-lead-out internal electrode 2 formed by the electrode pattern in the middle of the film layer accounts for 1 / 3 to 2 / 3 of the length of the non-lead-out internal electrode.
[0056] In some embodiments, the thickness of the terminal electrode at its narrowest point is between 5 μm and 20 μm, and the minimum interlayer spacing between the lead-out internal electrode 1 and the non-lead-out internal electrode 2 is 1.0 to 5.0 times the thickness of the terminal electrode at its narrowest point.
[0057] In some embodiments, the multilayer resistor is an NTC thermistor.
[0058] See also Figures 2a to 4 The embodiment of the present invention also provides a multilayer resistor, including a ceramic substrate made of multiple film layers, the substrate is provided with an internal electrode, an end electrode 4 and a bottom electrode 5, the internal electrode and the bottom electrode 5 are both printed electrode patterns, and grooves extending perpendicular to the stacking direction are formed on the two end surfaces of the substrate respectively (in the aforementioned manufacturing method embodiment, the grooves are formed after cutting along the holes 6), the end electrode 4 is formed by curing the electrode slurry filled in the groove, the end electrode 4 is connected to the bottom electrode 5, and an L-shaped external electrode structure is formed on the outer surface of the substrate. Figure 2a As shown, in some embodiments, the internal electrode includes an extraction internal electrode 1 and a non-extraction internal electrode 2 , and the terminal electrode 4 is also connected to the extraction internal electrode 1 .
[0059] The present invention provides a new type of multilayer resistor and a method for manufacturing the same, which can meet the market demand for smaller size and lower cost thermistors. By using laser ablation technology to open holes in the substrate and fill them with electrode slurry, connection and conduction of some areas between layers are achieved, simplifying the dipping or impregnation process of traditional NTC thermistors. The method of the present invention not only saves costs because it reduces the amount of electrode slurry used, but also simplifies the product manufacturing process, omitting the two major processes of dipping and burning, and speeding up the product manufacturing cycle. In addition, the scheme is conducive to the production of small-sized products because it avoids the limitation of high-precision requirements for dipping machines, making it possible to produce smaller-sized NTC thermistors. Finally, through the sintering and electroplating steps, a finished product with an "L"-shaped external electrode can be formed to meet the needs of mounting.
[0060] The specific embodiments of the present invention are further described below.
[0061] Embodiment 1
[0062] See also Figure 4 The specific manufacturing method of the first embodiment includes:
[0063] The first step: batching, using chemical coprecipitation or ball milling to obtain a uniformly mixed composite oxide containing transition metals such as Mn. Then, solvents, plasticizers, etc. are added to the powder to prepare a slurry with a certain viscosity.
[0064] The second step: tape casting, through the dry tape casting process, a single square film layer with a thickness of 10μm-100μm is made as a substrate.
[0065] Step 3: Drill holes according to Figure 3 The opening area and range shown are used to open holes at the locations where the electrode filling paste needs to be printed, so as to form holes 6.
[0066] Step 4: Printing, follow Figure 3 As shown, the electrode patterns are printed respectively, and the electrode paste fills the previously opened holes 6. The main components of the electrode paste can be metal materials such as palladium, platinum, gold, copper, nickel, and silver.
[0067] Step 5: Lamination: Multiple film layers and electrode patterns are laminated according to the required resistance value specifications and the rules in Figure 2, and a certain pressure is applied to press the film layers and electrode patterns together to form a block. The electrode pattern in the middle of the film layer is bonded to the electrode pattern at the bottom of the film layer through the electrode paste in the hole.
[0068] Step 6: Cut and cut the above blocks into Figure 3 The hole 6 is cut at the position shown, and the electrode pattern 7 in the middle of the film layer and the electrode pattern at the bottom of the film layer are exposed in the joint area at the hole 6 to form an end electrode 4. The electrode pattern at the bottom of the film layer after cutting forms a bottom electrode 5 connected to the end electrode 4. Figure 3 In the figure, the left side shows cutting at the hole 6 forming the terminal electrode 4 (top view), and the terminal electrode 4 is connected to the electrode pattern 7 for forming the lead-out internal electrode, and the right side shows cutting at the hole 6 forming the terminal electrode 4 (top view), and the terminal electrode 4 is not connected to the electrode pattern for forming the non-lead-out internal electrode 2.
[0069] Step 7: Sintering: sinter the cut semi-finished products at a high temperature of 1000-1300℃ to form dense ceramics.
[0070] Step 8: Electroplating: Electroplating the sintered ceramic body. Using common electroplating technology, first nickel or copper plating, then tin plating, and then cleaning and drying to obtain the finished NTC thermistor.
[0071] In summary, the present invention proposes a multilayer resistor and a manufacturing method thereof, which can realize a miniaturized, low-cost NTC thermistor. The method includes the steps of film making, laser opening, printing electrode slurry, lamination pressing, vertical cutting, sintering and electroplating. Through laser ablation technology, holes are opened on the substrate and filled with electrode slurry to achieve interlayer connection, omitting the traditional end-dipping process, simplifying the production process and reducing costs. After cutting, the end electrode and the bottom electrode are formed, sintered to form a dense ceramic structure, and finally electroplated to complete the finished product. This method is suitable for the manufacture of smaller resistors and improves production efficiency and product performance.
[0072] The above content is a further detailed description of the present invention in combination with specific / preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, without departing from the concept of the present invention, it can also make several substitutions or modifications to these described embodiments, and these substitutions or modifications should be regarded as belonging to the protection scope of the present invention. In the description of this specification, the description of the reference terms "an embodiment", "some embodiments", "preferred embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in combination with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily target the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In the absence of mutual contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples. Although the embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions and modifications can be made herein without departing from the scope of protection of the patent application.
Claims
1. A method for manufacturing a multilayer resistor, characterized in that: The following steps are involved: S1. Film layer: multiple film layers are made as substrates; S2. Opening holes: Opening holes at positions corresponding to electrodes on the substrate by laser ablation to form holes for filling electrode slurry; S3. Printing electrode slurry: printing electrode slurry on the substrate with holes, printing into an electrode pattern, and filling the holes; S4. Lamination pressing: stacking multiple film layers together and applying pressure to make them tightly bonded to form a multi-layer structured rectangular resistor block prototype; wherein the electrode pattern in the middle of the film layer and the electrode pattern at the bottom of the film layer are bonded together through the electrode slurry in the holes; S5. Cutting: vertically cutting the stacked rectangular resistor block along the hole position, so that the junction area between the electrode pattern in the middle of the film layer and the electrode pattern at the bottom of the film layer is exposed to form an end electrode, and the electrode pattern at the bottom of the film layer after cutting forms a bottom electrode connected to the end electrode; S6. Sintering: Sintering the cut semi-finished product to form a dense ceramic structure; S7. Electroplating: Electroplating the sintered porcelain body to obtain a finished product.
2. The method for manufacturing a multilayer resistor according to claim 1, wherein: In step S1, a single square film layer with a thickness of 10 μm-100 μm is formed by a dry tape casting process.
3. The method for manufacturing a multilayer resistor according to claim 2, wherein: The slurry used in the dry tape casting process is obtained by using a chemical coprecipitation method or a ball milling method to obtain a uniformly mixed composite oxide containing transition metals, and then a solvent and a plasticizer are added to the powder to prepare a slurry.
4. The method for manufacturing a multilayer resistor according to any one of claims 1 to 3, wherein: In step S3, the components of the electrode slurry include one or more of palladium, platinum, gold, copper, nickel, and silver.
5. The method for manufacturing a multilayer resistor according to any one of claims 1 to 4, characterized in that: In step S6, the cut semi-finished product is sintered at a high temperature of 1000-1300°C.
6. The method for manufacturing a multilayer resistor according to any one of claims 1 to 5, wherein: In step S7, nickel or copper is plated first, then tin is plated, and then cleaning and drying are performed to complete the electroplating.
7. The method for manufacturing a multilayer resistor according to any one of claims 1 to 6, wherein: The overlapping length between the lead-out internal electrode and the non-lead-out internal electrode formed by the electrode pattern in the middle of the film layer accounts for 1 / 3 to 2 / 3 of the length of the non-lead-out internal electrode.
8. The method for manufacturing a multilayer resistor according to any one of claims 1 to 7, wherein: The thickness of the terminal electrode at its narrowest point is between 5 μm and 20 μm, and the minimum interlayer spacing between the lead-out inner electrode and the non-lead-out inner electrode is 1.0 to 5.0 times the thickness of the terminal electrode at its narrowest point.
9. The method for manufacturing a multilayer resistor according to any one of claims 1 to 8, wherein: The multilayer resistor is an NTC thermistor.
10. A multilayer resistor, characterized in that: The invention comprises a ceramic substrate formed by stacking a plurality of film layers, wherein the substrate is provided with an inner electrode, an end electrode and a bottom electrode, wherein the inner electrode and the bottom electrode are both electrode patterns formed by printing, and grooves extending perpendicular to the stacking direction are respectively formed on the two end surfaces of the substrate, and the end electrode is formed by curing the electrode slurry filled in the groove, and the end electrode is connected to the bottom electrode, forming an L-shaped external electrode structure on the outer surface of the substrate.