KR100476027B1 - Method for manufacturing ceramic stacking device with built-in capacitor - Google Patents

Abstract

The present invention relates to a method of manufacturing a ceramic laminated device having a built-in capacitor, and to performing a photolithography process to produce a ceramic laminated device with a built-in capacitor having a small standard deviation by implementing a precise electrode pattern, when applying a high-frequency module module The effect is to improve the reliability of the.

Description

Method for manufacturing ceramic stacking device with built-in capacitor}

The present invention relates to a method for manufacturing a ceramic laminated device having a built-in capacitor, and more particularly, by performing a photolithography process to manufacture a ceramic laminated device with a built-in capacitor having a small standard deviation by implementing a precise electrode pattern, a high frequency module The present invention relates to a method for manufacturing a ceramic laminated element having a built-in capacitor for improving the reliability of the module when the application of the present invention.

In general, low temperature calcined multilayer ceramic circuit boards have the advantage of being able to use low melting point conductive metals such as silver, gold, and copper.

In addition, low-temperature calcined multilayer ceramic circuit boards are made of glass-ceramic composites fired at temperatures below 1000 ° C as the main raw material and have a low coefficient of thermal expansion, which is similar to that of silicon (Si) or gallium arsenide (GaAs) devices. Therefore, it can be used as a package substrate of an integrated circuit.

In particular, built-in ceramic capacitors are made of low-temperature fired ceramic circuit boards and applied to high frequency modules.

In order to manufacture such a built-in ceramic capacitor for a high frequency module, first, a green sheet must be made.

The green sheet is made by mixing a powder of a glass-ceramic composite with an organic binder, a solvent, a dispersant, and the like to produce a slurry, and passing the slurry through a tape caster to form and dry it.

Thereafter, the conductive paste prepared by mixing a conductive metal powder such as silver and gold, an organic binder, a solvent and a glass powder, and the like is screen printed on the green sheet.

Here, the screen printing method is a method of printing a desired circuit pattern on an upper surface of a substrate such as a green sheet or alumina by allowing the paste to pass through the screen mask on which the circuit pattern is formed and to exit only the pattern portion.

Then, the conductive paste is printed alternately on each green sheet, and then the respective green sheets are laminated and fired to form a ceramic package substrate incorporating a circuit pattern.

Of course, each green sheet is perforated so that the respective green sheets stacked by vias filled with conductive paste are electrically connected.

Meanwhile, circuit patterning was performed on the upper portion of the green sheet by screen printing, lamination and firing to prepare an embedded low temperature co-firing capacitor.

Capacitor manufacturing method using such a green sheet can be largely divided into two. First, there is a method of using the green sheet itself as a dielectric layer, and second, there is a method of forming a dielectric layer using a dielectric paste on the green sheet.

First, the method of using the green sheet itself as a dielectric layer is mainly to use the low dielectric constant of the low-temperature fired ceramic. The two electrodes printed with the conductive paste on the green sheet are alternately printed with a plurality of capacitors to have a desired capacity. I can make it.

In addition, the method of printing a dielectric paste on the green sheet may produce a high capacity capacitor that is difficult to obtain only by using a low temperature calcined ceramic substrate.

In the method of manufacturing a capacitor using such a dielectric paste, first, the lower electrode is printed on the green sheet with the conductive paste, and after drying, the dielectric paste is printed on the lower electrode.

At this time, the printing thickness or the number of times of the dielectric is adjusted to obtain the desired capacity.

After drying, the upper electrode is printed to form a capacitor structure, and when laminated and fired, the capacitor is completed.

Such conventional ceramic embedded capacitors utilize screen printing, and the pattern formed by the screen printing reduces the accuracy of printing due to the influence of the wires constituting the screen mask and the flow of paste after printing, and thus the desired pattern. It was difficult to implement the shape of the problem.

In addition, there is a limit in the resolution of the conductive wires and the spaces between the wires, and in the case of the capacitors, there is a problem in that there is a characteristic deviation in the substrate or between the substrates depending on the degree of alignment and pattern precision during screen printing. .

Accordingly, the present invention has been made to solve the problems described above, by performing a photolithography process to produce a ceramic laminated device with a built-in capacitor having a small standard deviation by implementing a precise electrode pattern, when applying a high-frequency module module SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a ceramic laminated device having a built-in capacitor that improves the reliability of the same.

A preferred aspect for achieving the above object of the present invention is to penetrate the green sheet and spaced apart from each other, punching a plurality of vias of the first group and the second group into the green sheet, and Filling a paste into each via to form a plurality of green sheets; Wrapping the plurality of vias and printing a photosensitive conductive paste on top of each of the plurality of green sheets; Among the plurality of green sheets, a photolithography process of exposing and developing the photosensitive conductive paste of some green sheets with a mask having a first electrode pattern is performed to remove portions other than the electrode patterns to cover each of the vias of the first group. A third step of forming separate first electrodes on the green sheets, respectively; A photolithography process of exposing and developing the photosensitive conductive paste of each of the remaining green sheets with a mask on which a second electrode pattern is formed to remove portions other than the electrode pattern to cover each of the vias of the second group, and to separate them. Forming a plurality of second electrodes on the green sheet, respectively; The green sheet having the second electrode is alternately stacked on the green sheet on which the first electrode is formed, wherein vias of the first group are electrically connected to vias of the first group, and vias of the second group are second group. A fifth step of electrically connecting and stacking the vias; Provided is a method of manufacturing a ceramic multilayer device having a built-in capacitor configured as a sixth step of firing the laminated green sheet.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

1A to 1D are diagrams illustrating a manufacturing process of a built-in ceramic capacitor according to the present invention. First, a plurality of vias 11 formed through a green sheet 10 and spaced apart from each other are formed of a first group and a second group. Is punched into the green sheet 10, and a conductive paste is filled into each via 11 to form a plurality of green sheets (FIG. 1A).

Here, the first group and the second group vias of the respective green sheets are one of a pair of vias adjacent to each other, one belonging to the first group, and the other belonging to the second group (see FIG. 2). , The first group via is '11a' and the second group via is '11b'.)

Therefore, the plurality of vias consist of pairs of vias that are adjacent to each other.

Thereafter, the plurality of vias 11 are wrapped and a photosensitive conductive paste 12 is printed on each of the plurality of green sheets 10 (FIG. 1B).

At this time, the photosensitive conductive paste 12 is kept at room temperature for a time that the paste can be planarized to improve thickness uniformity, and then dried in an oven at about 80 ° C. for 10 to 20 minutes.

Subsequently, a photolithography process of exposing and developing the photosensitive conductive paste of some green sheets of the plurality of green sheets with a mask on which a first electrode pattern is formed, and removing the portions other than the electrode pattern to separate the first electrodes. 12a, 12b, 12c, and 12d are formed on the green sheets, respectively (FIGS. 1C and 1D).

 The first electrodes 12a, 12b, 12c, and 12d surround each of the first group of vias described above.

Then, in the same manner as shown in FIGS. 1C and 1D, a photolithography process of exposing and developing a photosensitive conductive paste of each of the remaining green sheets with a mask having a second electrode pattern is performed to remove portions other than the electrode pattern. The second electrode is formed to surround each of the second group of vias, and second electrodes are formed on the green sheet.

When such a process is performed, a green sheet on which first electrodes are formed is manufactured, and a green sheet on which second electrodes are formed is manufactured.

The first electrodes surround the first group of vias and are separated, and the second electrodes surround the second group of vias, and are separated.

FIG. 2 is a diagram illustrating a state in which embedded ceramic capacitors according to the present invention are stacked, and the green sheet having the second electrode 22 formed on the green sheets 31 and 33 having the first electrode 21 formed thereon (FIG. 32 and 34 are alternately stacked, with the first group of vias 11a electrically connected to the first group of vias 11a, and the second group of vias 11b being the second group of vias 11b. ) To be electrically connected and stacked.

Thereafter, when the laminated green sheets 31, 32, 33, and 34 are fired at a temperature of 850 to 900 ° C, manufacturing of the embedded ceramic capacitor is completed.

That is, since the first electrodes are connected to the vias of the first group and the second electrodes are connected to the vias of the second group, electrical short between the first electrode and the second electrode does not occur.

3A and 3B illustrate a state in which a first electrode and a second electrode are formed in a conductive paste pattern formed on an upper portion of the green sheet according to the present invention, and FIG. 3A illustrates a state in which the first electrode pattern is formed in the green sheet. 3B shows a state in which the second electrode pattern is formed on the green sheet.

Therefore, the first electrode and the second electrode pattern are respectively formed in a shape opposite to each other, and when the above-described green sheets are stacked, the green sheets are stacked by placing the shapes of the first electrode and the second electrode pattern to be opposite to each other.

FIG. 4 is a view illustrating a state in which alignment vias are formed on an upper portion of the green sheet according to the present invention. In order to precisely align the mask with the mask during the photoetching of the conductive paste of the green sheet 10, the green sheet ( When punching a plurality of vias 10, an alignment via 15 is formed at the edge of the green sheet.

The alignment vias are aligned with the alignment marks 18 of the mask 17 aligned on the green sheet 10, as shown in FIG. 5, and then subjected to an exposure process. An electrode pattern can be formed.

The above-described green sheet has a non-aqueous property in which the binder component is not dissolved in water, and uses a glass-ceramic composite capable of low temperature co-firing, that is, firing at 850 to 900 ° C. The electrode is formed using a photosensitive conductive paste containing any one of low melting point metals selected from Ag, AgPt, Au, and Cu.

In the embedded ceramic capacitor of the present invention, as shown in Table 1, the characteristic value of the capacitors each of the electrodes does not have a standard deviation (percentage of the standard deviation with respect to the average value of the capacitances) of more than 2.5%. It can be seen that the standard deviation is much less than the capacitor produced by the conventional method having a. Here, the unit of measured capacitance is pF.

Capacitor number First layer capacitor 2nd layer capacitor 3rd layer capacitor Capacitance Standard Deviation Capacitance Standard Deviation Capacitance Standard Deviation One 0.670 1.92 1.203 1.30 1.872 2.34 2 0.784 1.51 1.416 1.94 2.227 1.71 3 0.889 1.25 1.607 1.30 2.537 1.57 4 1.134 1.22 2.030 2.39 3.196 1.38 5 1.467 1.35 2.657 1.08 4.264 1.13 6 1.823 1.80 3.363 1.40 5.359 1.33 7 2.125 0.85 3.995 1.29 6.401 1.57 8 2.724 1.01 5.080 1.06 8.180 1.20 9 3.273 1.65 6.155 1.31 9.950 1.28 10 3.554 0.98 6.730 1.86 10.777 1.40 11 3.869 0.93 7.326 0.84 11.850 2.14 12 4.174 1.16 7.955 1.23 12.848 2.00 13 5.771 0.97 11.137 1.09 18.083 1.72 14 7.176 0.72 14.077 0.99 22.680 1.23 15 3.383 1.20 6.158 0.53 9.734 1.68 16 4.155 0.74 7.647 0.65 12.064 1.44 17 5.119 0.56 9.548 1.02 15.005 1.03 18 6.158 0.88 11.488 0.94 18.120 0.83

As described in detail above, the present invention has the effect of improving the reliability of the module when the high frequency module is applied by manufacturing a ceramic multilayer device having a low standard deviation capacitor embedded therein by performing a photolithography process to implement a precise electrode pattern. .

Although the invention has been described in detail only with respect to specific examples, it will be apparent to those skilled in the art that various modifications and variations are possible within the spirit of the invention, and such modifications and variations belong to the appended claims.

1A to 1D are manufacturing process diagrams of the embedded ceramic capacitor according to the present invention.

2 is a view showing a state in which the built-in ceramic capacitor according to the invention stacked.

3A and 3B illustrate a state in which a first electrode and a second electrode are formed in a conductive paste pattern formed on the green sheet according to the present invention.

4 is a view illustrating a state in which alignment vias are formed on an upper portion of the green sheet according to the present invention.

5 is a view showing a state in which the mask is aligned on the top of the green sheet by matching the alignment mark of the mask and the alignment via of the green sheet according to the present invention.

<Description of the symbols for the main parts of the drawings>

10,31,32,33,34 Green Sheet 11: Via

11a: the first group via 11b: the second group via

12 photosensitive conductive paste

12a, 12b, 12c, 12d, 21: first electrode 15, alignment via

17: mask 18: alignment mark

22: second electrode

Claims (6)

A first step of penetrating the green sheet and spaced apart from each other, punching a plurality of vias of the first group and the second group into the green sheet, and filling the vias with conductive paste to form a plurality of green sheets. Wow; Wrapping the plurality of vias and printing a photosensitive conductive paste on top of each of the plurality of green sheets; Among the plurality of green sheets, a photolithography process of exposing and developing the photosensitive conductive paste of some green sheets with a mask having a first electrode pattern is performed to remove portions other than the electrode patterns to cover each of the vias of the first group. A third step of forming separate first electrodes on the green sheets, respectively; A photolithography process of exposing and developing the photosensitive conductive paste of each of the remaining green sheets with a mask on which a second electrode pattern is formed to remove portions other than the electrode pattern to cover each of the vias of the second group, and to separate them. Forming a plurality of second electrodes on the green sheet, respectively; The green sheet on which the second electrode is formed is alternately stacked on the green sheet on which the first electrode is formed, wherein the vias of the first group are electrically connected to the vias of the first group, and the vias of the second group are A fifth step of electrically connecting and stacking the vias of the second group; And a sixth step of firing the stacked green sheets stacked through the fifth step. The method of claim 1, Between the second and third steps, Flattening the photosensitive conductive paste printed at room temperature to uniform thickness of the photosensitive conductive paste at room temperature, and drying in an oven at 80 ℃ for 10 minutes to 20 minutes characterized in that the ceramic laminate having a built-in capacitor Method of manufacturing the device. The method of claim 1, The sixth step of firing, Method for producing a ceramic laminated device having a built-in capacitor, characterized in that carried out at a temperature of 850 ~ 900 ℃. The method of claim 1, Wherein the green sheet is a non-aqueous binder in which the binder component is not dissolved in water, the manufacturing method of the embedded ceramic capacitor, characterized in that the glass-ceramic composite. The method of claim 1, The photosensitive conductive paste is a method of manufacturing a built-in ceramic capacitor, characterized in that the low melting point of any one metal selected from Ag, AgPt, Au and Cu. The method of claim 1, In the first step, when the plurality of vias are punched into the green sheet, in the process of photographic etching the photosensitive conductive paste of the green sheet in the third step and the fourth step, the alignment mark of the mask and the precision are precise. Punching the alignment via to the edge (Edge) of each green sheet for alignment, characterized in that the manufacturing method of the embedded ceramic capacitor.