CN102163960B - Multilayer chip filter and preparation method thereof - Google Patents

Abstract

The invention discloses a multi-layer chip filter and a preparation method thereof. The filter is composed of two plate capacitors, three chip air-core inductors and two magnetic core inductors, and the three chip air-core inductors are arranged in sequence On the upper layer of the filter, two magnetic core inductors are respectively located at the left and right ends of the lower layer of the filter, and two plate capacitors are located in the middle of the lower layer of the filter, wherein the chip air core inductor is formed by printing with silver paste , the magnetic core inductor is formed by the ferrite material in the through-hole connecting two layers of silver conductors, and the plate capacitor is formed by the coupling of large-area silver conductors between different layers. The preparation method includes the steps of pretreatment, drilling, metal hole filling, ferrite material injection, printing, lamination, isostatic pressing, hot cutting, sintering and the like. The multi-layer chip filter is obtained by punching holes and injecting ferrite materials into the ceramic green ceramic sheet, which effectively solves the problems of delamination and fracture after different materials are mixed fired in the multi-layer chip filter, and improves the yield.

Description

A kind of multi-layer chip filter and its preparation method

technical field

The invention belongs to the technical field of manufacturing electronic components, and in particular relates to a filter and a preparation method thereof.

Background technique

At present, the traditional preparation and production of small-volume multilayer chip filters mainly include single-element form and LC structure form. In view of the shortcomings of the above two methods, the invention patent with the application number of 200810046266.4 discloses a multilayer chip filter and its preparation method. This kind of multilayer chip filter is to print the required magnetic core inductance on the whole On a layer of ferrite material, the ferrite material and other ceramic materials are stacked together for co-firing. The stacking sequence is dielectric ceramic/ferrite material/dielectric ceramic/ferrite material/…/iron Oxygen materials/dielectric ceramics. This method can theoretically realize a filter with a high-inductance magnetic core inductance, but due to the different sintering stresses of ferrite and ceramics, the co-fired substrate often has fault splitting, and the flatness is difficult to control. Therefore yield is very low, and practicability is not strong.

Contents of the invention

The object of the present invention is to solve the problems existing in the above method, and propose a multilayer chip filter and a preparation method thereof.

In order to achieve the above object, the technical solution of the present invention is: a multi-layer chip filter is composed of two plate capacitors, three chip air-core inductors and two magnetic core inductors, and the three chip air-core inductors are arranged in sequence. The upper layer of the filter, the two magnetic core inductors are respectively located at the left and right ends of the lower layer of the filter, and the two plate capacitors are located in the middle of the lower layer of the filter, wherein the chip air-core inductor is made of ceramic material The magnetic core inductance is made of two layers of silver conductors and the ferrite material in the through holes, and the plate capacitance is formed by coupling large-area silver conductors between different layers.

The present invention proposes a preparation method of a multilayer chip filter for the above-mentioned multilayer chip filter, which specifically includes the following steps:

Step 1: pretreatment, drying the used ceramic raw porcelain sheets, drying conditions: temperature 80-90°C, time 25-35 minutes;

Step 2: Drilling holes, that is, punching holes on the dried ceramic green sheets, wherein the diameter of the magnetic core inductor is less than 1mm, and the diameter range of the air-core inductor and the interlayer connecting wire is 0.1-2.0mm;

Step 3: Metal hole filling, that is, filling the through hole with metal slurry. The filled ceramic green ceramic sheet needs to be dried to solidify the metal in the hole. Drying conditions: temperature 65-75°C, time 10-15 minute;

Step 4: Ferrite material injection, inject ferrite material on the ceramic green sheet where the magnetic core inductance needs to be realized, and dry it. Drying conditions: temperature 65-75°C, time 10-15 minutes ;

Step 5: Printing, each layer of ceramic green ceramic sheet forms a circuit pattern through precision screen printing;

Step 6: Lamination, that is, the printed graphics and the ceramic green ceramic sheets forming interconnected holes are laminated together at a temperature of 25-45°C and a pressure of 5-10MPa to form a complete multi-layer substrate blank body;

Step 7: Isostatic pressing, performing isostatic pressing on the multi-layer substrate green body, that is, using the thermoplasticity of the ceramic green sheet to perform isostatic pressing, the isostatic pressing process is carried out in a vacuum environment, and the isostatic pressing conditions are: pressure 20～40MPa, temperature 35～60℃;

Step 8: hot cutting, cutting the laminated multi-layer green ceramic sheet before sintering to form individual filters;

Step 9: sintering, put the hot-cut ceramic green body into a furnace for debinding and sintering, and the sintering temperature is 850-950°C. Finally, the multilayer chip filter of the present invention is obtained.

Beneficial effects of the present invention: the magnetic core inductance of the multilayer chip filter of the present invention is composed of two layers of silver conductors and the ferrite material in the through holes thereof. Oxygen material is used to obtain a multi-layer chip filter, which effectively solves the problems of delamination and fracture after different materials are mixed and fired in the multi-layer chip filter, and greatly improves the yield.

Description of drawings

Fig. 1 is a schematic diagram of a multilayer chip filter provided by the present invention.

Fig. 2 is an equivalent circuit diagram of the multilayer chip filter provided by the present invention.

Fig. 3 is a flowchart of the preparation method of the multilayer chip filter provided by the present invention.

Detailed ways

Specific embodiments of the present invention are given below in conjunction with the accompanying drawings.

The multilayer chip filter is shown in Figure 1: it consists of two plate capacitors, three chip air-core inductors and two magnetic core inductors. Three chip air-core inductors are arranged sequentially on the upper layer of the filter, two magnetic core inductors are respectively located at the left and right ends of the lower layer of the filter, and two plate capacitors are located in the middle of the lower layer of the filter. The chip air-core inductor is made by printing silver conductors on ceramic materials, the magnetic core inductor is made of two layers of silver conductors and ferrite materials in the through holes, and the plate capacitor is made of large interlayers Area silver conductor coupling is formed.

In terms of electrical connections, the equivalent circuit of the multilayer chip filter of the present invention is shown in Figure 2: the air-core inductors L1, L2, and L3 are made by printing silver conductors on the ceramic material, wherein the air-core inductors L1 and L3 is respectively connected to the input and output electrodes of the whole filter. Core inductors L4 and L5 consist of two layers of silver conductors with ferrite material (core) in their vias. The plate capacitor is formed by the coupling of large-area silver conductors between different layers, and is connected in parallel with the magnetic core inductance, and connected to the ground electrode plate of the entire filter.

The flow chart of the preparation method of the multilayer chip filter is shown in Figure 3, which specifically includes the following steps:

Step 1: Pretreatment, that is, drying the ceramic raw porcelain sheets used in a drying furnace, drying conditions: temperature 80-90°C, time 25-35 minutes;

Step 2: Drilling holes, that is, punching holes on the dried ceramic green sheets, wherein the diameter of the magnetic core inductor is less than 1mm, and the diameter range of the air-core inductor and the interlayer connecting wire is 0.1-2.0mm;

Step 3: Metal hole filling, that is, filling the through hole with metal slurry. The filled ceramic green ceramic sheet needs to be dried to solidify the metal in the hole. Drying conditions: temperature 65-75°C, time 10-15 minute;

Step 4: Ferrite material injection, inject ferrite material on the ceramic green sheet where the magnetic core inductance needs to be realized, and dry it. Drying conditions: temperature 65-75°C, time 10-15 minutes ;

Step 5: Printing, each layer of ceramic green ceramic sheet forms a circuit pattern through precision screen printing;

Step 6: Lamination, that is, the printed graphics and the ceramic green ceramic sheets forming interconnected holes are laminated together at a temperature of 25-45°C and a pressure of 5-10MPa to form a complete multi-layer substrate Body;

Step 7: Isostatic pressing. Isostatic pressing is performed on the multi-layer substrate green body, that is, isostatic pressing is carried out by utilizing the thermoplasticity of the ceramic raw ceramic sheet. The isostatic pressing process is carried out in a vacuum environment. The isostatic pressing conditions are: pressure 20~ 40MPa, temperature 35～60℃;

Step 8: hot cutting, cutting the laminated multi-layer green ceramic sheet before sintering to form individual filters;

Step 9: sintering, put the hot-cut ceramic green body into a furnace for debinding and sintering, the sintering temperature is 850-950°C, and finally obtain the multilayer chip filter of the present invention.

The above example is only a preferred example of the present invention, and the use of the present invention is not limited to this example. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in this document. within the scope of protection of the invention.

Claims (1)

1. a method of preparing multilayer chip filter, described multilayer chip filter, by two capacity plate antennas, three chip air core inductors and two magnetic core inductance form, three chip air core inductors are sequentially arranged in the upper strata of described filter, two magnetic core inductance lay respectively at the two ends, left and right of the lower floor of described filter, two capacity plate antennas are positioned at the centre of the lower floor of described filter, wherein said chip air core inductor is made by the silver conductor printing on ceramic material, the Ferrite Material of described magnetic core inductance in two-layer silver conductor and through hole thereof forms, described capacity plate antenna is formed by the large area silver conductor coupling between different layers,

It is characterized in that, described method comprises the steps:

Step 1: preliminary treatment, adopted ceramics green ceramic chip is dried to drying condition: 80～90 ℃ of temperature, 25～35 minutes time;

Step 2: punching, on the ceramics green ceramic chip of drying, punch, wherein the diameter of magnetic core inductance is less than 1mm, and the diameter range of air core inductor and interlayer connecting line is 0.1～2.0mm;

Step 3: metal filling perforation, in through hole, fill metal paste, the ceramics green ceramic chip after filling needs drying and processing, make in hole metal-cured, drying condition: 65～75 ℃ of temperature, 10～15 minutes time;

Step 4: Ferrite Material injects needs the position of realizing magnetic core inductance to inject Ferrite Material, and it is carried out to drying and processing, drying condition: 65～75 ℃ of temperature, 10～15 minutes time on ceramics green ceramic chip;

Step 5: printing, makes every layer of ceramics green ceramic chip form circuitous pattern by precise silk screen printing;

Step 6: lamination,, the ceramics green ceramic chip of the figure printing and formation through-hole interconnection, under 25～45 ℃ of temperature, pressure 5～10MPa condition, overlap together, form a complete multilager base plate base substrate;

Step 7: wait static pressure, multilager base plate base substrate is waited to static pressure, utilize the thermoplasticity of ceramics green ceramic chip to wait static pressure, wait static pressure process to carry out in vacuum environment, the described hydrostatic pressure condition that waits is: pressure 20～40MPa, 35～60 ℃ of temperature;

Step 8: earnestly, cut with shaping filter individual to the laminated ceramic chips after lamination before sintering;

Step 9: sintering, the ceramic green is earnestly put into stove binder removal sintering, sintering temperature is 850～950 ℃.

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