KR100334025B1 - Method for fabricating multi-layer ceramics package - Google Patents

Abstract

The present invention utilizes aqueous solvents and / or organic solvents, enhances fill workability and tensile strength, enhances the electrical conductivity of metallized wiring, and utilizes specialized reduced atmosphere firing to achieve high precision dimensions, high density, high electrical conductivity, The present invention relates to a multilayer ceramic package having high dielectric properties, and to which the present invention relates, a sintering aid made of alumina (Al ₂ O ₃ ), SiO ₂ , MgO, CaO compound, Al ₂ O ₃ , SiO ₂ , MgO, CaO Plasticizers, wetting agents, peptising agents, antifoaming agents, etc. can be selectively added and mixed with sintering aids composed of, TiO ₂ , Cr ₂ CO ₃ compounds or sintering aids of Talc, CaCO ₃ , Cr ₂ CO ₃ , TiO ₂ compounds Alumina slurry is produced, and the resulting alumina slurry is vacuum degassed, tape casted, via hole formed, pattern printed, laminated, and calcined under reduced atmosphere to form an alumina sintered body, followed by selective plating of metal materials. As, it is possible to manufacture the multi-layer ceramic package with a high density, high thermal conductivity, low thermal expansion coefficient, a low insulation resistance, a low resistivity, the characteristics of high bonding strength.

Description

METHOD FOR FABRICATING MULTI-LAYER CERAMICS PACKAGE}

The present invention relates to a multilayer ceramic package, and more particularly, to a method of manufacturing a multilayer ceramic package suitable for use in high integrated circuits.

In recent years, electronic-related devices such as computers and peripherals, electronic and communication devices, etc. are rapidly increasing in functionality, miniaturization, and light weight. This phenomenon is caused by the breakthrough of semiconductor devices, that is, IC and LSI.

On the other hand, wiring boards are used for interconnecting devices to semiconductors, for interacting with input / output devices, and the like, and the signals transmitted and received between them are extremely high enough to satisfy high-performance performance. Therefore, the wiring length in the wiring board needs to be short in order to satisfy the high speed of the signal.

However, due to technical limitations, the reduction of the planar area in the wiring board is approaching the limit. At present, miniaturization, high integration, and high functionalization of semiconductor devices such as LSI require higher density wiring in the wiring board. It is true.

To this end, conventionally, glass fiber reinforced epoxy resin and copper metallized printed boards are mainly used as wiring boards, but multilayer ceramic wiring boards in which tungsten or molybdenum metallization is applied to alumina ceramics are recently used due to limitations in wiring area. In particular, multilayer ceramic packages are required for hybrid integrated circuit boards, multilayer circuit boards for electronic circuits, stacking capacitors, and piezoelectric elements that require a thin sheet of about 0.03-1 mm. While high integration and miniaturization are easy, they require stringent characteristics, that is, high density molded sheet manufacturing technology.

In other words, the high density molding sheet manufacturing technology produces a slurry by mixing alumina powder with a binder, a plasticizer, and a solvent, and a slurry produced under a doctor-blade which is controlled at regular intervals on a moving transport film. It is a method of manufacturing a green sheet of constant thickness by passing it.

At this time, the required characteristics of the green sheet should be: (1) no secondary agglomerate, small particle orientation and uniform orientation, (2) high packing density, and (3) thickness direction in the sheet surface should be uniform. (4) free from cracking and good surface roughness, (5) good lamination bonding such as heating and pressing, and should not be separated during sintering, (6) scribing, hole punching Mechanical strength to the extent that elongation and deformation do not occur in the back, (7) when screen printing on the green sheet, the W-paste does not bleed, does not expand, and (8) disintegrates in small amounts during the sintering process. Lost carbides should not be produced and (9) not degraded, changed, etc. in a particular environment.

In particular, in the case of the alumina wiring board, the preform containing the metallized wiring is fired and solidified. At this time, several tens of percent shrinkage occurs and is accompanied by approximately 30% shrinkage in area. Therefore, firing at the same time as the metallization wiring is required to reduce the firing atmosphere in order to prevent oxidation of the metallized metal, and the organic binder used in forming the green sheet is lost in the firing of the reducing atmosphere. At this time, since the ceramics and the metallization are in a state in which the powder of the preform is fixed with the binder, the filling state is different depending on the particle size and the mixed state of the powder. Therefore, there is a need for a technique for controlling many factors such as sintering reaction of powder during firing, bonding of ceramics and metallization, bonding of mutual shrinkage, and the like.

Therefore, there is a need for a method for improving the characteristics such as high-precision dimensional control and metallized bond strength, and an optimization technique capable of realizing insulation and anti-aging of metallization wired at minute intervals while realizing mass production in the field. However, at present, it is still in a small quantity production and laboratory level.

Accordingly, the present invention is to solve the above problems of the prior art, using an aqueous solvent, by varying the paste viscosity for via holes and for printing to improve the filling workability, improve the tensile strength, It is an object of the present invention to provide a method for manufacturing a multilayer ceramic package that can enhance electrical conductivity.

Another object of the present invention is to use an organic solvent, and to manufacture a multilayer ceramic package which can improve filling workability, improve tensile strength, and improve electrical conductivity of metallized wiring by varying paste viscosity for via hole and printing. To provide a way.

Another object of the present invention is to provide a method for producing a multilayer ceramic package having high precision, high density, high conductivity, and high dielectric properties by using specialized reducing atmosphere firing.

The present invention according to one embodiment for achieving the above object is used in a highly integrated circuit, and in the method for producing a multilayer ceramic package having a structure in which at least two layers are laminated and bonded, the alumina (Al ₂ O ₃₎ powder A first step of adding and mixing an aqueous solvent, a plasticizer, a wetting agent, and a peptizing agent to a sintering aid composed of SiO ₂ , MgO, and CaO compounds to form a primary mixture; A second process of adding and mixing a predetermined amount of a binder and an antifoaming agent to the produced primary mixture to generate an alumina slurry; A third process of vacuum degassing for a predetermined time so that the produced alumina slurry has a desired viscosity; A fourth process of sheeting the vacuum degassed alumina slurry by tape casting to produce an alumina green sheet; A fifth process of forming a via hole and an alignment mark via hole in each of the green sheets to correspond to a shape of a target ceramic package; A sixth step of forming an electrode pattern on each of the green sheets through pattern printing using a conductor paste; A seventh process of generating a multilayer ceramic structure by stacking n green sheets generated through the fifth and sixth processes using respective alignment mark via holes; An eighth step of generating a multilayer ceramic sintered body by simultaneously firing the produced multilayer ceramic structure in a kiln with a reducing atmosphere of nitrogen and hydrogen gas; And a ninth process of selectively plating a portion of the multilayer ceramic sintered body with a metal material, thereby completing the multilayer ceramic package.

According to another aspect of the present invention, a method of manufacturing a multilayer ceramic package having a structure in which at least two layers are laminated and bonded to a high-integrated circuit, comprising: Talc, CaCO ₃ , Cr ₂ O ₃ A first step of adding and mixing an organic solvent to a sintering aid comprising a TiO ₂ compound to produce a primary mixture; A second process of adding and mixing alumina (Al ₂ O ₃ ), a solvent slurry, an organic solvent, an aqueous solvent, a plasticizer, a binder, and a humectant to the produced primary mixture to form an alumina slurry; A third process of vacuum degassing for a predetermined time so that the produced alumina slurry has a desired viscosity; A fourth process of sheeting the vacuum degassed alumina slurry by tape casting to produce an alumina green sheet; A fifth process of forming a via hole and an alignment mark via hole in each of the green sheets to correspond to a shape of a target ceramic package; A sixth step of forming an electrode pattern on each of the green sheets through pattern printing using a conductor paste; A seventh process of generating a multilayer ceramic structure by stacking n green sheets generated through the fifth and sixth processes using respective alignment mark via holes; An eighth step of generating a multilayer ceramic sintered body by simultaneously firing the produced multilayer ceramic structure in a kiln with a reducing atmosphere of nitrogen and hydrogen gas; And a ninth process of selectively plating a portion of the multilayer ceramic sintered body with a metal material, thereby completing the multilayer ceramic package.

According to another aspect of the present invention, there is provided a method of manufacturing a multilayer ceramic package having a structure in which at least two layers are laminated and bonded to a high-integrated circuit, comprising: Talc, CaCO ₃ , Cr ₂ O ₃ , a first process of adding and mixing a mixed organic solvent containing a plurality of organic solvents to a sintering aid composed of a TiO ₂ compound to form a primary mixture; A second process of adding and mixing alumina (Al ₂ O ₃ ) and a plasticizer to the resulting primary mixture to produce a secondary mixture as a secondary mixture; A third process of adding and mixing a binder to the produced secondary mixture to generate an alumina slurry; A fourth process of vacuum degassing for a predetermined time so that the produced alumina slurry has a desired viscosity; A fifth process of sheeting the vacuum degassed alumina slurry by tape casting to produce an alumina green sheet; A sixth step of forming a via hole and an alignment mark via hole in each of the green sheets to correspond to a shape of a target ceramic package; A seventh step of forming an electrode pattern on each of the green sheets through pattern printing using a conductor paste; An eighth process of stacking n green sheets generated through the sixth and seventh processes using each alignment mark via hole to generate a multilayer ceramic structure; A ninth step of generating a multilayer ceramic sintered body by simultaneously firing the produced multilayer ceramic structure in a kiln with a reducing atmosphere of nitrogen and hydrogen gas; And selectively plating a part of the produced multilayer ceramic sintered body with a metal material, thereby providing a method of manufacturing a multilayer ceramic package, the tenth process of completing a multilayer ceramic package.

1 is a flowchart illustrating a process of manufacturing a multilayer ceramic package according to a preferred embodiment of the present invention;

2 is a graph showing changes in braid height, feed rate, slurry viscosity and green sheet thickness,

3 is a graph showing the relationship between the shrinkage of the molding density, length, and width direction,

4 is a graph showing the relationship between slurry viscosity and sheet thickness;

5A and 5B are graphs showing a comparison of cross-sectional shapes when a conductor paste is printed on a green sheet,

6A and 6B are graphs showing the cross-sectional shape comparisons before and after heat pressurizing the conductor paste;

7a and 7b is a graph showing the shrinkage change of the green sheet in the printing drying process,

8A, 8B and 8C are cross-sectional views of a lamination bonding process of a four-layer structure,

9A and 9B are graphs showing the relationship between the plastic shrinkage rate at the time of hot press bonding;

10 is a graph showing the change in the pressing force and the sheet thickness change during hot press bonding;

11 is a graph showing a change in sintered density and shrinkage rate according to firing temperature;

12a to 12e are photographic views showing the microstructure of the electron microscope according to the firing temperature,

FIG. 13 is a graph showing the region of suitable firing conditions in the production furnace of W-metalization alumina ceramics,

14 is a graph showing the relationship between W-metallization bond strength and firing conditions;

15 is a graph showing the relationship between alumina content and metallization bond strength in ceramics,

16 is a structural diagram of a continuous production furnace,

17A, 17B and 17C are graphs showing temperature-time curves and firing schedules during firing,

18 is a graph showing the water vapor concentration of the reducing atmosphere gas through the humidifier,

19A and 19B are graphs showing the relationship between the plastic shrinkage rate and the sintered density fired in an arbitrary atmosphere with mixing conditions and sheet thickness as factors;

20A and 20B are graphs showing the relationship between sheet orientation and plastic shrinkage rate based on mixing conditions and sheet thickness;

21 is a graph showing the relationship between water vapor concentration and plastic shrinkage rate,

22A and 22B are graphs showing changes in organic binder content and plastic shrinkage in four-layer structure lamination,

23 is a graph showing the relationship between the gas supply amount and the plastic shrinkage rate in a kiln on a mass production scale.

The above and other objects and various advantages of the present invention will become more apparent from the preferred embodiments of the present invention described below with reference to the accompanying drawings by those skilled in the art.

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

1 is a flowchart illustrating a process of manufacturing a multilayer ceramic package according to a preferred embodiment of the present invention.

Referring to FIG. 1, in the present invention, an organic solvent and a dispersant are added and mixed with an aqueous solvent and an alcoholic solvent to a sintering aid composed of SiO ₂ , MgO, and CaO compounds in an alumina (Al ₂ O ₃ ) powder according to one embodiment. Performing a primary mixing process for a predetermined time to obtain a primary mixture, or according to another embodiment, an aqueous system in an sintering aid composed of SiO ₂ , MgO, CaO, TiO ₂ , Cr ₂ O ₃ compounds in Al ₂ O ₃ powder Mixing of Solvent and Alcohol-Based Solvent A primary mixing step of adding and mixing an organic solvent and a dispersant is performed for a predetermined time to obtain a primary mixture (step 102). In addition, according to another embodiment of the present invention by performing a first mixing step of adding and mixing a mixed organic solvent, a plasticizer and a binder to a sintering aid consisting of Talc, CaCO ₃ , Cr ₂ O ₃ , TiO ₂ compounds for a predetermined time It is also possible to obtain a primary mixture.

Subsequently, a secondary mixture process in which BL-1z or an acrylic resin emulsion, a plasticizer and alcohols (methanol) is additionally mixed and mixed with the primary mixture is performed for a predetermined time to obtain a secondary mixture (step 104).

Next, a vacuum defoaming process is performed on the secondary mixture obtained through the secondary mixing to prepare an alumina slurry (step 106). Since the evaporation of the aqueous solvent occurs severely during such vacuum degassing, it is necessary to precisely control the viscosity of the slip. Since the slip viscosity is substantially increased according to the vacuum degassing time, it is very important to find a time that is shortest and well degassed.

Accordingly, the inventors of the present invention, through many experiments, calculated the proper defoaming time and slurry viscosity. That is, in the mixture according to an embodiment of the present invention, a slurry viscosity of about 12,000-13,000 cps was found to be suitable, and it was found that about 12 minutes is preferable as an appropriate degassing time. In the mixture according to the example, a slurry viscosity of about 15,000-20,000 cps was found to be suitable, and about 12 minutes was preferable as an appropriate defoaming time. In addition, in the mixture according to another embodiment of the present invention, the slurry viscosity of about 12,000-13,000 cps was found to be suitable, as in the above-described embodiment, and as a suitable defoaming time for this, about 12 minutes. It was found that is preferable.

Subsequently, the alumina slurry obtained through the vacuum defoaming process is sheeted by a tape casting process to prepare an alumina green sheet (step 108). At this time, the factors affecting the casting thickness may include a doctor braid height, a conveying speed, a slurry viscosity, the thickness of the green sheet is proportional to the doctor braid height, and inversely proportional to the conveying speed of the carrier film. Therefore, it is necessary to perform a tape casting process with sufficient consideration of these factors, and the inventors of the present invention have established optimization conditions through many experiments, and the optimization conditions obtained through the experiments will be described later in detail. Will be described.

Next, a via hole punching process is performed to form an alignment mark via hole, which is necessary for alignment between the package and the via hole for electrically connecting the wirings of the stacked packages for multilayer ceramic packaging (step 110). The electrode layer is formed by printing a conductor paste such as W or Mo on the green sheet on which the via hole is formed through a pattern printing process using a dry layer, followed by drying (Step 112). At this time, the conductive paste filled in the via hole and the conductive paste pattern printed are preferably different in viscosity, in order to smoothly fill the via holes.

Subsequently, the green sheets manufactured through the above-described processes are aligned and stacked in several layers using an alignment mark via hole, and then a lamination process is performed to form a structure of a multi-layer ceramic package composed of N layers of green sheets. Form (step 114). At this time, lamination conditions such as temperature, pressure and time are very important. That is, since the green sheet is molded with an acrylic resin emulsion binder and there is thermoplasticity, bonding between the sheets is achieved by heating and pressing. Since the bonding strength at this time needs to withstand post-processing, it is preferable to maintain the binder amount and the adhesive strength appropriately, which will be described in detail through the following examples.

In addition, debinder firing, main firing and cooling treatment are carried out by simultaneous firing in a reducing atmosphere using a tennel type electric furnace, for example, H ₂ -N ₂ gas, that is, simultaneous green sheet, conductor electrode and metallization. By firing, a multilayer ceramic sintered body is produced (step 116). At this time, the relationship between the plastic shrinkage rate during heating and pressurization, the change in the pressing force and the thickness of the sheet, the relationship between the change in the plastic density and the shrinkage rate according to the firing temperature, and the relationship between the alumina content in the ceramic and the strength of the metallization bond are performed. Factors, the description of these relationship factors will be described in detail in the following examples.

Finally, the multilayer ceramic sintered body is selectively plated with a metal material such as gold nickel, for example, to complete the multilayer ceramic package (step 118).

Therefore, in the multilayer ceramic package manufactured according to the present invention, the workability of filling is improved by varying the viscosity of the conductor paste for the via hole and the conductor paste for the wiring, and the tensile strength is improved by improving the bonding property with the ceramics, The electrical conductivity of metallized wiring can be enhanced.

In addition, by firing the multilayer ceramic sintered body through reduction firing having an optimum temperature range and atmosphere, a multilayer ceramic package having high precision, high density, high conductivity, high dielectric properties, and the like can be manufactured.

Example 1

In the present embodiment, as shown in Table 1 below, 92.4% Al ₂ O ₃ , 5.6% SiO ₂ , 1.5% MgO, and 0.5% CaO were used as base compositions, and alumina (Al ₂ O ₃ ) had an average particle diameter. The ALM44 from Sumitomo, Japan, which is 2.5 μm, Talc is made in China with an average particle diameter of 6-7 μm and a particle size distribution of 0.2-20 μm, and clay has an average particle diameter of 1-2 μm and a particle size distribution. Clay of 0.2-15 μm was used.

TABLE 1

material Weight ratio (%) Raw material cost Alumina 90 talc 6 clay 4 Oxide composition Al ₂ O ₃ 92.4 SiO ₂ 5.4 MgO 1.7 CaO 0.5

That is, alumina and a sintering aid, talc and clay were put into a ball mill, and water, a peptizing agent, a plasticizer, and a wetting agent were added to the ball mill and mixed firstly for 24 hours to make a uniform particle size. Alumina balls Ø20mm-240kg and Ø30mm-360kg were used. The weight ratio (A / A + B) of the weight (A) of the alumina plus sintering aid and the ball weight (B) is preferably about 0.26.

At this time, the aqueous additives used in the primary mixing and the conditions of the manufacturing process are shown in Table 2 below.

TABLE 2

material function Addition amount (g) ratio(%) H ₂ O Solvent 465.0 16.3 MgO Grain growth inhibitors 3.8 0.1 Polyethylene Glycol # 2000 Plasticizer 120.0 4.2 Butyl benzyl phthalate Plasticizer 88.0 3.1 Nonionic Oxyl Phenoxyl Ethanol Humectant 5.0 1.8 Aryl sulfonic acid Discourse 70.0 2.5 Alumina Raw material 1,900.0 66.6 Acrylic resin emulsion Binder 200.0 7.1 Wax emulsion Antifoam 2.0 0.07

Ball mill capacity: 600g

Ball mill filling amount: 600kg

Ball mill rotation speed: 31 RPM

Grinding and Mixing Time: 24 hours

Binder input time: 24 hours after milling

Binder Mixing Time: 4 Hours

The present inventors tested the change of the agglomerated particle diameter with mixing time, and as a result, it was found that the agglomerated particle diameter was reduced with the mixing time to become the primary particle diameter. That is, it was found that the aggregated particle diameter was 8.4 µm for 3 hours of pulverized mixing, decreased to 6 µm for 10 hours, and 3.6 µm for 24 hours of mixing. Therefore, in the present Example, the mixing time was set to 24 hours.

Next, an acrylic resin emulsion binder was added to the primary mixture and mixed in a ball mill for 4 hours, and then a wax-based antifoaming agent was added and mixed for 10 minutes to obtain a secondary mixture, and a vacuum defoaming process was performed on the secondary mixture. The alumina slurry was prepared, and since the evaporation of the aqueous solvent occurred severely during the vacuum degassing, accurate viscosity viscosity control was needed, that is, the slip viscosity increased according to the vacuum degassing time, so it was necessary to find the shortest and the best time for degassing. Experimental results show that it is 10 to 15 minutes, more preferably 12 minutes, which is approximately 12,000-15,000 cps.

Here, the surface roughness and density change according to the flux composition ratio (MgO: CaO = 13.8: 1, 6.4: 1, 3.76: 1) appear as the surface roughness (Ra) decreases as the amount of MgO added increases. It is related to the grain growth inhibitory effect of MgO.

In addition, the surface roughness value was almost constant according to the change of the firing temperature (for example, 1560 ° C, 1580 ° C, 1600 ° C), and at a composition ratio of MgO: CaO = 13.8: 1, 6.4: 1, the firing temperature was As the density increased, the composition ratio of MgO: CaO = 3.76: 1 was almost unchanged.

As a result, it can be seen that the variables of the surface roughness values are closely related to the solvent composition, which affects the surface roughness values because they are segregated as a glass phase or a second crystal phase at the Al ₂ O ₃ surface and grain boundaries during sintering. It's crazy.

In addition, it was found that the flux composition ratio (MgO: CaO = 13.8: 1, 6.4: 1, 3.76: 1) influences the sintering shrinkage rate, and therefore, the composition ratio of MgO: CaO = 3.76: 1 has the sintering shrinkage anisotropy. It can be seen that it is the best control, and the plastic shrinkage rate depends on the particle size in terms of particle size and particle size distribution of the main body, but even if the average particle size is the same, the plastic shrinkage rate is changed, the sintering shrinkage rate (Sℓ, Sw) This is especially a feature that requires careful attention and care.

On the other hand, the alumina substrate requires accurate dimensions, and the factors influencing the casting thickness include a doctor braid height, a feed rate, and a slurry viscosity. The thickness change of the green sheet by these factors is shown in detail in FIG. 2. It is. That is, after adjusting the slurry viscosity to 12,000-20,000 cps and setting the moving speed of the carrier film to 300 mm / min, the relationship between the doctor braid height and the green sheet was investigated. As can be seen from FIG. It can be seen that the thickness is proportional to the height of the doctor braid.

In addition, as a result of examining the relationship between the moving speed of the carrier film and the thickness of the green sheet, the thickness of the green sheet is inversely proportional to the moving speed of the carrier film. -It can be seen that a large thickness change occurs between 300mm / min.

3 is a graph showing changes in plastic shrinkage when the sheets having different molding densities are sintered in the longitudinal direction Sl, the width direction Sw, and the thickness direction St, respectively. Here, a longitudinal direction has shown the same direction as the moving direction of a conveyance film (carrier film), and has shown the orthogonal direction to the width direction.

Referring to Figure 3, even in the sheet manufactured under the same conditions, if the molding density is different, the shrinkage rate is changed, it can be seen that this shrinkage rate change has different anisotropy.

This phenomenon occurs because the alumina particles and the binder are oriented during molding, not spherical, and the shrinkage rate is affected by the particle size of the raw material and the shape of the particles, and is directly dependent on the molding density. Therefore, the relationship between the mold density and the shrinkage ratio is large in the difference between the shrinkage ratios Sl and Sw in the surface direction and the shrinkage ratio in the thickness direction. There will be no.

As a result, it can be clearly seen from FIG. 3 that the plastic shrinkage in the longitudinal direction Sl, the width direction Sw, and the thickness direction St increases as the molding density increases.

4 is a graph showing the relationship between the viscosity of the slurry and the thickness of the green sheet, it can be seen that the thickness becomes thinner as the viscosity increases, and the slurry viscosity is fixed at 6.8 × 10 ³ to 8.2 by fixing the height of the doctor braid to 1.3 mm. When changing to x10 ³ cps, it can be seen that the thickness of the pre-green sheet is reduced from 0.82 to 0.75 mm, and the thickness of the sintered sheet after firing is reduced from 0.67 to 0.62 mm.

Therefore, it can be seen that a change in slurry viscosity changes the thickness of the green sheet, so that each process requires a particularly strict management and control for adjusting the slurry viscosity.

On the other hand, the optimization condition of tape casting is a process of making a flexible sheet by volatilizing an aqueous solvent. The drying principle is drying while moving in the form of a belt conveyor. The heating part is divided into four parts so that the temperature and air flow amount can be adjusted for each part. It is.

At this time, if the temperature is rapidly increased or the blowing and exhaust are strong, the evaporation speed of the solvent is increased, which causes problems in the molding sheet. Therefore, the condition that the surface evaporation rate and the internal diffusion rate of the solvent coincide with the temperature gradually increases. Do not cause cracks and other defects. Considering these points, the results of the tape casting optimization are shown in Table 3 below.

TABLE 3

Section＼ condition Temperature Minutes Wind speed (0 -10) exhaust One Room temperature 20 0 closeness 2 Room temperature 60 One closeness 3 40 ℃ 40 2 Natural circulation 4 60 ℃ 10 2 Natural circulation 5 80 ℃ 10 4 Forced circulation 6 100 ℃ 10 6 Forced circulation 7 120 ℃ 5 6 Forced circulation 8 Room temperature 30 3 Forced circulation

Next, a pattern printing process is performed after forming a via hole for electrically aligning the wirings of the packages stacked for the multilayer ceramic package through via hole punching, and an alignment mark via hole necessary for the alignment between the packages. .

FIG. 5 is a graph showing the cross-sectional shape of the conductive paste when printed on the green sheet, in which 5a is a case where the W paste is printed on the green sheet, and 5b is a Ag-Pd paste on the alumina substrate after firing. Each case is shown, and the printing paste and printing conditions here are as follows.

Screen material: stainless steel mesh

Reticle diameter, resist thickness: Ø30㎛, 80㎛

Numerical aperture: 250 / in ²

Printing press: PRESCO

Printing paste, Viscosity: W paste, 90,000 cps / EMC-Ag-Pd paste (EX8703) 250,000 cps

Heating and pressurization condition after printing: Bronze (Cu + Sn) plate, 46㎏ / ㎝ ² , 150 ℃ 10 minutes

In the printing of the green sheet, the paste solvent is absorbed by the capillary phenomenon in the sponge-like green sheet, and the solidification of the printing paste proceeds rapidly, resulting in a severe inclination of the cross section, which is caused by the paste falling off the screen. to be. In addition, the solidification proceeds in the substrate after firing without absorbing the solvent, and the printed surface remaining on both the screen and the printed surface is also deformed, resulting in an acid shape (mountain shape) due to the surface tension.

That is, printing of tungsten paste on ceramics after firing is substantially impossible due to the high bleeding phenomenon and low viscosity. However, in the printing method on the green sheet according to the present invention, an appropriate tooth cross section can be obtained even in fine wiring width, and fine printing is possible because it has a solvent absorption characteristic due to the air permeability by the fine pores in the green sheet.

6 is a graph showing the cross-sectional shape of the printed paste before and after heat pressing of the conductor paste, wherein 6a shows the printed cross-sectional shape before the heating press and 6b shows the printed cross-sectional shape after the heat pressing, and the green sheet after printing is made of a bronze plate 150 It shows the cross-sectional shape after heating and pressurizing at 46 ° C., 46 kg / cm ² for 10 minutes, and the thickness of the tungsten metallization layer was reduced to 1/2, which was observed to be embedded in the green sheet. It is important.

In addition, the particle arrangement of the green sheet and the bonding state of the binder have a great influence on the mechanical properties of the sheet. That is, since the deformation amount of the green sheet is increased to the high stress side and the binder content is increased to the low stress side, the ceramic particle diameter and the dispersibility of the binder have a great influence on the processing amount.

Therefore, in view of this point, the present invention is set to an optimum condition of an alumina average particle diameter of 4 µm, a binder of 5.3%, wet ball mill mixing, first mixing 24 hours, and secondary mixing 30 minutes.

7A and 7B are graphs showing a change in shrinkage rate of a green sheet in a printing drying process. The shrinkage change was measured by repeating printing and drying a green sheet of 0.6 mmt seven times. That is, cavity molding on the green sheet → printing the 1-layer metallization pattern → drying (110 ℃ 15 minutes) → 1-layer alumina paste printing → drying (110 ℃ 15 minutes) → 1-layer alumina paste printing → drying (110 ℃ 15 min) → 2-layer metallization pattern printing → drying (110 ℃ 15 minutes) → 2-layer alumina paste printing → drying (110 ℃ 15 minutes) → 2-layer alumina paste printing → drying (110 ℃ 15 minutes) → 3-layer Metallization pattern printing → drying (110 ℃ 15 minutes) was repeated seven times the drying step to measure the shrinkage rate, where the metallization pattern has an area ratio of the surface to be printed 10%, alumina insulating layer printing has a 90% area. Printing was carried out, and the density of the green sheet was 2.43 g / cm 3 and 2.35 g / cm ² , and the mixing conditions were wet mixed for 25 hours for the former and 20 hours for the latter, and the shrinkage ratio measurement was about 0.001 mm. Measured under a microscope.

As a result, the shrinkage rate of the sheet with short mixing time and low molding density was about 2 times higher than that of the standard sheet (25 hour wet mixed sheet), and the binder was dissolved in the printing paste and dried after the sheet expanded. The rearrangement of the ceramic particles in the sheet occurs, and it was found that drying and shrinkage tended to increase as the printed layer increased from the beginning.

Meanwhile, the green sheets are aligned by using an alignment mark via hole and stacked in multiple layers (ie, multilayer substrates), and then a laminate process forms a structure of a multilayer ceramic package including N layers of green sheets. Lamination conditions (ie, temperature, pressure, time, etc.) are very important factors.

In other words, the green sheet is formed of an acrylic resin-based emulsion binder, and the thermoplastic sheet is bonded to the sheet when heated and pressurized. At this time, the adhesive strength needs to withstand post-processing so that the amount of the binder and the adhesive strength must be properly adjusted. .

To this end, the inventors of the present invention measured the adhesive strength after the green sheet was heated and pressurized for 15 minutes in an atmosphere of 150 ℃, 45 kg / mm ^{2 to} prepare a tensile test piece. As a result of the measurement, the optimum binder content was 12%, and the adhesive strength at this time was 16-18 kg / mm ² , and it was found that no binding was carried out at more than 12%, 15%, and 20%. The large bubble phase appeared in front, and the gas layer was analyzed to interfere with adhesion.

Here, the adhesive strength is 7kg / cm ² at 5.3% binder content, there is no problem in practical use enough to withstand hole punching, and the creep of the green sheet and the dimensional stability during the process is excellent This content was made into the standard.

In addition, the green sheet was N ₂ 8.0m ³ / h, H ₂ 2.5m ³ / h, H ₂ O 0.042 g / ℓ atmosphere firing at 1600 ℃ for 1 hour to investigate the adaptive plastic shrinkage rate of each binder content binder, The plastic shrinkage was 15.5-15.7% in the content of 5.3-15%, whereas the plastic shrinkage was significantly increased in the binder content of 15% or more. As a result, the amount of the binder was limited to 15%.

FIG. 8 is a cross-sectional view illustrating a process of stacking a green sheet in a four-layer structure as an example, wherein 8a is a cross section of an alignment structure for lamination, and 8b is a cross section of an aligned state through a via hole for alignment marks. 8c shows the cross section after heat pressurizing for 10 minutes at 150 degreeC and 46 kg / cm <^2> atmospheric conditions, respectively.

9A and 9B are graphs showing the relationship between the plastic shrinkage rate at the time of heating and pressurization. Four sheets of 0.48mmt green sheet (thickness error 0.007mm) and one sheet having a thickness difference of 0.03mm are attached. After hot press bonding, it is a graph showing the results of measuring the plastic shrinkage rate by separating each of the 14 positions. Here, the thick portion represents the portion having a small plastic shrinkage rate because the pressing force is larger than the thin portion at the time of hot press bonding.

Typically, thicker green sheets result in smaller plastic shrinkage (the same tendency under no-pressure conditions), with the result that the plastic shrinkage of the thickest part (1.934 mmt) is 13.85% during four-layer heat pressurization of the green sheet, The plastic shrinkage rate of the thinnest part (1.905 mmt) is 14.23%, and it can be seen that the plastic shrinkage rate decreases as the thickness of the heat press lamination increases, and the plastic shrinkage rate increases as the layer thickness decreases.

10 is a graph showing the change in pressing force and the thickness of the raw sheet during hot press bonding. As the pressing force increases, the thickness of the green sheet tends to be thinner, and the thickness is constant at 80 kg / cm ² or more. Could know. In other words, this means that the molding density of the green sheet is the highest density as the pressing force limit value. That is, that a, 20㎏ / ㎝ ² under pressure, under reduced thickness and 0.037mm, 50㎏ / ㎝ ² pressure, and having a reduced thickness 0.044mm, under 80㎏ / ㎝ ² pressure 0.047mm As can be seen from Figure 10 There was no change in the above. Therefore, the thickness reduction at 45 kg / cm ² showed the most suitable pressing force at 0.042.

11 is a graph showing a change in the firing density and shrinkage rate according to the firing temperature, and the firing temperature was changed at intervals of 20 ° C. from 1550 ° C. to 1630 ° C., and the alumina substrate was calcined in a nitrogen or hydrogen atmosphere, and the firing atmosphere Was selected according to the properties of the raw materials and the properties of the products. Sintering of a basic alumina sheet is normally performed by heating up to the temperature required for sintering, decomposing | disassembling and removing organic substances, such as a binder, at the temperature of 300 degreeC-500 degreeC. At this time, since the alumina containing the sintering aid (solvent aid) belongs to the liquid phase reaction, the characteristics of the sintered compact are very important because densification is determined by the firing density.

That is, FIG. 11 shows the relationship between the change in the length shrinkage ratio (Sl) and the area shrinkage ratio (Sw) according to the firing temperature and the firing density within the same molding density, and the firing density varies greatly with the firing temperature. It can be seen that a stable firing density can be obtained at 1550 ° C. or higher, and the shrinkage anisotropy is controlled to a relatively good value although the length and width shrinkage ratios have slightly anisotropy depending on the firing temperature.

12 is a photograph showing an electron microscopic structure according to the firing temperature, 12a shows that some pores are observed due to the non-growth of the sintered state at the firing temperature 1550 ℃, Figure 12b is a sintered state at the firing temperature 1570 ℃ It is good and shows the state that the particles grew compared to 1550 ° C. and the glass phases were partially agglomerated with silicates. In addition, as shown in 12c and 12d, when fired at the firing temperatures of 1590 ℃ and 1610 ℃, it is shown that the glass phase with the grain growth is more observed, as shown in 12e, a large growth at the firing temperature 1630 ℃ Particles are visible, and the alumina particles on the surface are almost covered with glass, indicating that they are under-fired.

That is, the mineral phase change of alumina ceramics according to the firing temperature is the α-Alumina, Talc, Clay crystals of α-Alumina, MgO · SiO ₂ , Mg ₂ Al ₂₄ Si ₅ O ₁₈ at 1400 ℃ Α-Alumina, MgO · SiO ₂ , 3Al ₂ O ₃ · SiO ₂ , and were detected as α-Alumina at 1610 ° C.

FIG. 13 is a graph showing suitable firing condition regions in a production furnace of tungsten metallized alumina ceramics, showing the sintering state and metallization state of the ceramics by varying the firing temperature and atmospheric wetness of the production furnace. That is, after firing the sample which laminated | stacked the green sheet which printed 32.15 * 11.73 * 0.5mmt and four layers of tungsten metallization wiring, the dimension 27.5x10.0mm + 1% is a result of making it defect.

As can be seen from FIG. 13, on the high temperature side, the dimension becomes larger due to the expansion of pores in the ceramics, and a defect occurs on the low temperature side, and the dimensional defect due to the micro grains occurs on the low temperature side, and on the lower side of the wetness, the binder decreases due to the increase of residual carbon. Ceramic defects occur, and metallization loss occurs in the higher degree of wetting. Therefore, the effective range as metallization is a low wettability first, and the peel strength of metallization is 2.0 kg / mm which is practically effective.

Further, as is clear from the graph, it can be seen that the water temperature range of the optimum wet humidifier at the time of firing at 1590 ° C is approximately 33 ° C-50 ° C, most preferably 40 ° C.

14 is a graph showing the relationship between the tungsten metallization bond strength and the firing conditions. The amount and defect boundary of the metallization is shifted to the left as the firing temperature increases, and the water temperature of the wet humidifier is lowered.

That is, the glassy diffusion in the tungsten layer ceramics is likely to occur in the wet atmosphere firing, and the loss of tungsten oxide occurs. On the high temperature side, this phenomenon is accelerated and the strength of the ceramic-tungsten is weakened, and the metallization sintering is insufficient on the low temperature side. Due to the high glass penetration, the plating adhesion becomes insufficient, and this phenomenon leads to a decrease in the strength of the interface, which leads to product defects. Therefore, since the increase in glass in the metallization increases the electrical resistance of the wiring, the firing conditions must be controlled in a narrow range.

15 is a graph showing the relationship between the alumina content in the ceramic and the metallization bond strength. In 1520 ° C., the bond strength decreases with the increase in the alumina content, and becomes almost zero at 97%. It shows a peak value at 93% and shows that the overall bond strength is improved compared to 1520 ° C. Here, the presence of the peak value is a result of excessively invading the low-alumina content ceramics from the sintered ceramic metallization into the glassy metallization, but the same result is obtained even in all simultaneous firing.

Therefore, it is assumed that there is a peak at an alumina content of 90% or less when the calcination temperature is low, and therefore, a peak exists above the 93% content at a temperature higher than 1600 ° C.

Therefore, the glass phase in the ceramic may be considered to leak if the lack of penetration of metallization is a cause of strength increase and decrease, and the metallization is porous and airtight when the penetration of metallization is insufficient.

Therefore, although the mutual bonding by the glass phase component is dominant, the influence of the alumina particle diameter is also large, and it is also very important that proper grain control is performed under the optimum firing conditions according to the alumina content.

FIG. 16 shows a schematic structure of the production furnace, wherein the filling indentation device 161, the preheating table 162, the main gas inlet 163, the electric furnace body 164, the auxiliary gas inlet 165 and cooling The ceramic structure including the base 166 and laminated at the time of firing is preheated through the preheating zone 162 during the preheating section (sections 0-4 of FIG. 17A), and the main firing section (sections 4-10.6 of FIG. 17A). Is fired in the electric furnace body 164 during the cooling, and is cooled through the cooling table 166 during the cooling section (section 10.7-15.5 in FIG. 17A).

As shown in FIG. 17C, the rate of temperature increase, which greatly affects the loss and firing process of the organic binder in the co-firing, is set at two conditions of 500 ° C./h and 200 ° C./h close to mass production conditions, and is shown in FIG. 17B. As shown, run at 190 ° C./h.

At this time, the temperature of 500 ℃ / h is impossible due to the lack of capacity of the production furnace, so once the temperature inside the production furnace raised to a predetermined temperature and put the sample at the entrance of the production furnace at 500 ℃ / h speed than the low temperature side, 190 ℃ / h, 200 ° C / h was put into the sample and the temperature was raised by the program of the production furnace, the cooling was 100 ° C / h-500 ° C / h in the production furnace.

In addition, the loss of the binder was maintained at 800 ° C. for 1 hour, and the sintering stability was maintained at the highest temperature for 1 hour. The gas flow rate was set to 1000-1100 L / h of nitrogen gas and 200 to 300 L / h of hydrogen gas in the production furnace, and the mixed gas was wetted. The water temperature is set to 40 ℃ by the humidifier water temperature, and the wet gas supply pipe is wound around the heating element and maintained at 60-80 ℃, and after 200-250 ℃ heating, it is prevented from entering condensation. It was.

At this time, when the temperature was lowered, the humidifier heating power was turned off at the same time as the temperature was lowered, and the dry mixed gas was transferred at around 450 ° C., and the flow rate of hydrogen and nitrogen mixed gas was 0.038 g / at the humidifier water temperature of 40 ° C. L (water weight / mixed gas capacity).

Here, the temperature profile of the production furnace is heated to 533 ° C./h up to 800 ° C. and maintained for 1 hour, heated to 150 ° C./h up to 1600 ° C. for 1 hour, and then cooled by furnace. The gas flow rate is 700 L / h nitrogen and 160 L / h hydrogen, and the flow rate is changed by keeping the hydrogen content constant at 18%. The gas pressure in the production furnace changes back and forth on the basis of pressurization of 0.06 atm rather than atmospheric pressure. I was. At this time, the amount of water vapor in the gas is 0.042 g / h.

18 is a graph showing the water vapor concentration of the reducing atmosphere gas through the humidifier, using hydrogen and nitrogen gas to create a reducing atmosphere, mixed in the piping of the furnace and supplied in the furnace, under the humidifier tank to maintain a constant water temperature The mixed gas is bubbled through to supply the wet mixed gas into the furnace.

Referring to FIG. 18, it is shown that when the humidifier temperature is 40 ° C., the concentration of water vapor in the mixed gas is 0.038 g / L, and attention must be paid to the concentration of water vapor through the humidifier since tungsten metallization is lost at 50 ° C. or higher.

19A and 19B are graphs showing the relationship between the plastic shrinkage rate and the sintered density which were fired in a H ₂ + N ₂ + H ₂ O atmosphere at 1600 ° C. with mixing conditions and sheet thickness as factors.

First, one sheet of 0.5 mmt green sheet and two sheets of 17 x 35 mm are laminated and calcined at 1600 DEG C in a reducing atmosphere, and the average value is obtained by measuring the shrinkage rate and sintered density after casting in the casting direction (S L).

Referring to FIGS. 19A and 19B, as the mixing time (dry + wet time) increases, the forming density becomes the maximum point, but the plastic shrinkage rate of the sheet laminated two sheets moves in a direction smaller than one sheet, and the sinter density is angular. It is a state which becomes high under mixing conditions. This is an unexplained part unless shrinkage (Sw, St direction) other than the casting direction becomes large.

That is, in the case of wet 20 hour mixing, the sintered density of one sheet is 3.42 g / cm 3 and the casting shrinkage rate is 15.23%, the sintered density of the two laminated sheets is 3.43 g / cm 3, and the casting direction plastic shrinkage rate is At 16.25%, it can be seen that the sintered density is about the same but the plastic shrinkage rate is about 1% higher for the two-sheet laminated sheet.

In addition, in the case of wet 30 hour mixing, the sintered density of one sheet was 3.42 g / cm 3, which is the same as the 20 hour wet mixing, but the casting direction plastic shrinkage was 13.6%, which is about 1.63% less than the 20 hour wet mixing. It can be seen that the sintered density of the two sheets is 3.46 g / cm 3 and the casting shrinkage rate is 15.84%, which is slightly higher than the one sheet sheet compared to 20 hours of mixing, but the casting shrinkage rate is increased by 2.24%. It can be seen.

20A and 20B are graphs showing the relationship between the sheet orientation and the plastic shrinkage rate based on the mixing conditions and the sheet thickness, and the relationship between the casting direction shrinkage rate SL and the width direction shrinkage rate Sw is exactly Sℓ ≒ Sw, It is shown that there is a relationship S l <St with the shrinkage rate St in the direction. In general, the control of Sl and Sw is very important in electronic components, and it is necessary to clearly identify the cause of the change in shrinkage orientation.

Referring to FIG. 20A, the plastic shrinkage rate of one sheet is directly proportional to Sℓ and Sw, and when wet mixed for 20 hours, Sw = 14.3% when Sℓ = 15%, and when wet mixed for 20 hours regardless of Sℓ and St. When S = 15%, St = 19%, and 30 hours wet mixing, there was no correlation between St = 18.8%, and the plastic shrinkage in the thickness direction was large as S <<St.

Referring to FIG. 20B, the plastic shrinkage rate of the two-sheet laminated sheet is directly proportional to Sl and Sw as in the above-mentioned one sheet sheet, and Sw = 16.5% when Sl = 16.3% during 20 hours wet mixing, and Sl and St are Regardless, there was no correlation between St = 18.8% when Sℓ = 15.2% when wet mixing for 20 hours, and St = 18.4% when wet mixing for 30 hours, and Sℓ <St. .

FIG. 21 is a graph showing the relationship between water vapor concentration and plastic shrinkage rate. The effect of water vapor concentration in the firing atmosphere was investigated. Specifically, the product was calcined after stabilizing for 8 hours in a continuous large-scale tunnel furnace. As a green graph, the results were also measured and expressed as one sheet.

Here, the shrinkage ratio is expressed as a variation range of three times the average value and the standard deviation, and the variation of the four-sheet stacking sheet becomes 2-4 times compared to the shrinkage variation range of the one-sheet sheet. The variation range of the sheet tends to decrease. Moreover, although shrinkage rate fluctuated according to the magnitude | size of a sheet, it was confirmed that there is no big change in the magnitude | size of the fluctuation | variation. Therefore, increasing the steam concentration tends to decrease the shrinkage range, but as known as the tungsten redox curve at the H ₂ / H ₂ O ratio, the water vapor concentration at the actual level is within the range of sublimation loss by oxidizing tungsten. . At this time, it is necessary to control the water vapor concentration to a level at which the reaction rate is not harmful, that is, 0.099 g / l or less.

Subsequently, by laminating one and four layers of green sheets, the size of the sample was changed to measure a change in shrinkage rate according to the water vapor concentration. As shown in FIG. 21, the water vapor concentration in the firing atmosphere was in the range of 0.02 to 0.10 g / L. As a result of adjusting and adjusting the plastic shrinkage rate, it was found that the optimum conditions for the water vapor concentration were between 0.040 and 0.045 g / L for the first and fourth layer sheets. In other words, at the water vapor concentration of 0.10 g / l or more, tungsten metallization is lost and disappeared, and as the number of sheets laminated or the sample size is large, the plastic shrinkage rate tends to increase.

Therefore, when the water vapor concentration is 0.040-0.045 g / L, which is the optimum condition, the plastic shrinkage rate of the single layer sheet (27.0 x 8.5 mm, 0.5 t) is 16.05%, and the four layer sheet (27.0 x 8.5 mm, 0.5 t x 4). The plastic shrinkage of the layer) was 14.75%, and the plastic shrinkage was 14.17% when the size of the four-layer sheet was increased to 32.3 × 11.7 mm.

22A and 22B are graphs showing changes in the organic binder content and the plastic shrinkage rate in the four-layer laminated structure. In the reduction atmosphere firing, the increase in the oxygen concentration is promoted by the loss of the binder. Was measured.

First, as a sample, a sheet having a size of 32.15 × 11.73mm and a thickness of 0.5t was laminated in one and four layers, and the firing conditions were N ₂ 8 m ³ / h and H ₂ 2.5 m ³ / h H ₂ O (H ₂ O / Gas amount) was fired in a large turnnel continuous furnace at 0.042 g / l.

As a result, there was a difference in the plastic shrinkage rate by the binder content (3-6%) in the one-layer sheet, but the variation in the shrinkage rate was very small, and the same result was observed in the four-layer sheet, compared to the one-layer sheet in the four-layer sheet. The fluctuation range was large and the range of fluctuation increased with the amount of binder.

Thus, it has been found that reducing the binder has the effect of reducing the variation in plastic shrinkage rate of the sheet, which in turn means that the decrease in the binder decreases the amount of binder loss, thereby reducing the plastic shrinkage rate.

FIG. 23 is a graph showing the relationship between the gas supply amount and the plastic shrinkage ratio in a mass production kiln.

As is well known, the state of the atmosphere in the kiln is very important of the various factors directly or indirectly involved in the manufacture of the sheet. Therefore, the atmosphere in the kiln needs to meet very demanding control conditions. That is, since the manufacturing process with a large variation in the plastic shrinkage rate of the sheet is greatly influenced by the gas supply conditions in the kiln, in this embodiment, the relationship between the gas supply amount and the plastic shrinkage rate was investigated.

At this time, the experiment was carried out in a large turnnel, the firing conditions, 1600 ℃, the main gas supply conditions were changed up and down and the auxiliary gas amount was reduced, the sheet size of 6.35 × 9.53 mm, 0.5t × 3 layers And 6.40x19.25mm and the sheet | seat of 0.5tx4 layer were baked.

Analysis of FIG. 23 obtained as an experimental result shows that the shrinkage rate is small, the fluctuation range is small under the condition that the gas supply amount is small, and the variation in the plastic shrinkage rate is increased when the auxiliary gas amount is decreased. In the change of shrinkage rate by the gas flow rate, the main gas N ₂ 8.0m ³ / h, H ₂ 2.5m ³ / h, auxiliary gas N ₂ 4.0m ³ / h to the main gas N ₂ 9.0m ³ / h The plastic shrinkage is kept constant, and the shrinkage is 15.3%-15.2% in the three-layer sheet (6.35 x 9.53 mm, 0.5t x 3 layers), and in the four-layer sheet (6.40 x 19.25 mm, 0.5t x 4 layers). It is almost 14.0%-13.9%, but there is little change when the gas volume increases further.

Therefore, as can be seen from the above experimental results, N ₂ 8.0m ³ / h, H ₂ 2.5m ³ / h-N ₂ 9.0m ³ / h, H ₂ 2.5m which is a constant interval with little change in plastic shrinkage rate The range of ³ / h is suitable for atmospheric firing by the main gas supply amount.

In addition, as the gas pressure in the kiln increases, the plastic shrinkage rate decreases. As a result of analyzing the plastic shrinkage rate by changing the gas pressure in the kiln to 0.03 atm, 0.06 atm, and 0.09 atm, the firing shrinkage rate at 0.06 atm is most stable. 14.0%, and the plastic shrinkage rate is largely changed from 13.5 to 14.1% at 0.03 atm, and under 0.09 atm, the decomposition gas in the sheet is suppressed by pressure, and the entire kiln is stable due to the encapsulation effect of the binder, so that the shrinkage rate and fluctuation range are Becomes smaller.

Thus, as can be seen from the above experimental results, it is necessary to maintain a condition that promotes the disappearance of the binder in the sheet by always supplying a fresh gas to the sheet surface.

Finally, a multilayer ceramic package is completed by selectively plating a metal material such as gold nickel on the multilayer ceramic sintered body manufactured through the processes as described above.

Therefore, according to the present embodiment, a multilayer ceramic package having excellent filling workability, improved tensile strength, improved electrical conductivity of metallized wiring, high precision dimensions, high density, high electric conductivity, high dielectric properties, and the like is provided. It can manufacture.

[Experiment 2]

In the present embodiment, as a basic composition, Al ₂ O ₃ 92.0%, SiO ₂ 24.0%, MgO 1.3%, CaO 0.45%, TiO ₂ 0.70%, Cr ₂ O ₃ 1.55%, and alumina is ALCOA (USA) A -14 (average particle diameter 4 µm, specific surface area 36 m ² / g), A-15-H (average particle diameter 2.8-3.2 µm, specific surface area 3-4 m ² / g), and talc is the central particle diameter PS 325 mesh having a 16.4 ± 4.0 μm (particle size distribution 5-20 μm), limestone (CaCO ₃ ) was a white lime powder 325 mesh having a central particle diameter of 16.4 ± 4.0 μm (particle size distribution 4-24 μm), Cr ₂ O ₃ used a primary reagent having a purity of 99% or higher, and TiO ₂ used a JIS K8073 reagent grade 1 (purity of 98.5% or higher and an average particle diameter of 0.15 to 0.25 µm), respectively.

In addition, the alumina ball Ø30mm-120kg (material HD alumina) and Ø20mm-80kg (material HD alumina) were used for a 200ℓ ball mill, and the weight ratio of the weight (A) and the ball weight (B) of alumina + sintering aid ( A / A + B) is preferably about 0.245, and the solvent mixing specifications are shown in Table 4 below.

TABLE 4

Combination order material usage Weight (kg) ratio(%) Stage 1 Talc 44.40 68.52 CaCO ₃ 5.40 8.33 Cr ₂ O ₃ 10.20 15.74 TiO ₂ 4.80 7.41 Total solids 64.80 100.00 Methanol 52.50 81.02 Tier 2 Methanol 59.00 91.05

First, Talc, CaCO ₃ , Cr ₂ O ₃ , TiO ₂ in a ball mill in a basis weight based on the solvent combination ratio of the material is added, and then ball milling at RPM: 30 for 66 hours. After ball milling, methanol material as an organic solvent was added to the ball mill according to the combination ratio of Table 3 above, followed by two-step ball milling at RPM: 30 for 1 hour to prepare a slurry of a solvent batch as a sintering aid of the alumina combination. Transfer to hopper.

Subsequently, in order to add alumina and a sintering agent solvent slip and to prepare an aqueous slurry, pure water, a peptizing agent, a plasticizer, and a humectant are added and mixed in four stages so as to have a uniform particle size.

Here, the equipment for producing the mixed slurry used alumina balls Ø60mm-300kg (HD) and Ø30mm-700kg (HD), slurry tank in a 1000L ball mill, where the weight of the alumina + sintering aid (A) and the ball The weight ratio (A / A + B) of the weight (B) is preferably about 0.377, and the combination ratio of the mixed slurry in one step is shown in Table 5 below.

TABLE 5

material usage Weight (kg) ratio(%) Alumina (A-14) 270.00 33.08 Alumina (A-15-H) 270.00 33.08 Flux-Ⅴ solids 64.80 7.94 Flux-Ⅴ methanol 111.50 13.66 Dibutol glycolate (DBG): plasticizer 22.00 2.70 Polyethylene Glycol (PEG): Plasticizer 3.35 0.41 Methanol: Organic Solvent 70.00 8.58 Pure Water: Aqueous Solvent 4.67 0.57 sum 816.32 100.02

That is, the materials having the above composition ratio in a 1000L ball mill was milled for 4 hours at RPM: 12 and mixed in one step.

Subsequently, 69.00 kg (56.10%) of a binder (BL-1z) and 54.00 kg (43.90%) of an organic solvent (methanol) were added thereto, followed by mixing in two stages for 20 hours at RPM: 12, followed by plasticizer (Dibuthyl Phthalate: DBP). ) 5.40kg (8.94%) and 55.00kg (91.06%) of organic solvent (methanol) are added thereto, followed by mixing in two stages at RPM: 10 for 1 hour.

Finally, 100.00 kg of the waste green sheet is added and mixed for 15 hours to prepare a slurry.

Next, by performing a vacuum degassing process under a condition of 22 ± 2 ℃ through a vacuum degassing process, a slurry having a viscosity of about 15,000-20,000 cps is prepared, wherein the viscosity adjustment time is most preferably 6-12 hours.

Subsequent processes, namely, tape casting, hole punching and shape processing according to the shape of the ceramic package, electrode pattern printing, lamination and lamination, reducing atmosphere firing, metal material plating, and the like are performed in Example 1 described above. Are substantially the same as those of Therefore, in order to avoid unnecessary duplication description, detailed description here is abbreviate | omitted.

Therefore, according to the present embodiment, the same result as in the above-described embodiment 1, that is, the filling workability is excellent, the tensile strength is improved, the electrical conductivity of the metallized wiring is enhanced, the high precision dimension, high density, high electric conductivity , A multilayer ceramic package having high dielectric properties and the like can be produced.

Example 3

In this example, 51.20 kg of Talc (center particle size 16 ± 4.0 μm, particle size distribution 5-20 μm), CaCO ₃ (center particle size 16 ± 4.0 μm, particle size distribution 4-24 μm) 8.90 kg, Cr ₂ O as the basic composition ₃ (purity 99% or more) 35.00 kg, TiO (average particle size 0.15-0.25 μm) 12.00 kg, dispersant 10.00 kg, a mixture of a mixed organic solvent was prepared, a high-density alumina ball with a diameter of 30 mm, 700 kg and 60 mm, 130 kg The prepared mixture material was charged into a loaded 1000 L ball mill and mixed firstly for 24 hours.

Here, the mixed organic solvent is, for example, 200.00 kg of toluene or xylene aromatic, 56.50 kg of alcohol ethanol, 13.50 kg of butanol, 0.81 kg of isopropyl alcohol, methyl ethyl ketone (Methyl Ethyl Keton: MEK) (Or MIBK) 130.00 kg, but the mixing weight ratio between the aromatic solvent, the alcohol solvent and the ketone solvent is preferably in the range of 2.0: 0.7: 1.3-4.0: 1.4: 2.6.

Next, 300.00 kg of alumina having an average particle diameter of 4 µm (particle size distribution 2-44 µm), 300.00 kg of alumina having an average particle diameter of 2.8-3.2 µm (particle size distribution 0.6-5 µm), and 5.50 kg of polyethylene glycol (PEG # 300) as a plasticizer. And 45.30 kg of dibutyl glycorate were added thereto, followed by secondary mixing for 4 hours.

Again, 146.50 kg of alumina with an average particle diameter of 4 μm, 146.50 kg of alumina with an average particle diameter of 2.8-3.2 μm, and 114.10 kg were added with a binder ratio of BL-1z and BM-Sz in a 90:10 ratio for 20 hours. Tertiary mixing produces a slurry.

Subsequently, the vacuum defoaming process is performed for about 12 minutes, thereby preparing a slurry having a viscosity of about 12,000-13,000 cps.

Each of the following processes, namely, tape casting, hole punching and shape machining according to the shape of the ceramic package, electrode pattern printing, lamination and lamination, reducing atmosphere firing, metal material plating, and the like, are described in Embodiments 1 and Substantially the same as those in 2. Therefore, in order to avoid unnecessary duplication description, detailed description here is abbreviate | omitted.

Therefore, according to the present embodiment, the same result as in the above-described embodiment 1, that is, the filling workability is excellent, the tensile strength is improved, the electrical conductivity of the metallized wiring is enhanced, the high precision dimension, high density, high electric conductivity , A multilayer ceramic package having high dielectric properties and the like can be produced.

As described above, according to the present invention, the sintering aid of alumina (Al ₂ O ₃ ), SiO ₂ , MgO, CaO compound, Al ₂ O ₃ , SiO ₂ , MgO, CaO, TiO ₂ , Cr ₂ CO ₃ A sintering aid or a sintering aid composed of Talc, CaCO ₃ , Cr ₂ CO ₃ , TiO ₂ compounds, and optionally adding and mixing a plasticizer, a wetting agent, a peptizing agent, an antifoaming agent, and the like to produce an alumina slurry. The slurry is vacuum degassed, tape casted, via-hole formed, pattern printed, laminated and calcined in a reducing atmosphere to form an alumina sintered body, followed by selective plating of a metal material, thereby providing high density, high thermal conductivity, low thermal expansion rate, low insulation resistance, low specific resistance, and high resistance. It is possible to manufacture a multilayer ceramic package having the properties of adhesive strength.

Claims (55)

In the method of manufacturing a multilayer ceramics package used in a high-integrated circuit, and having a structure in which at least two layers are laminated and bonded, A first process of adding and mixing an aqueous solvent, a plasticizer, a humectant, and a peptizing agent to a sintering aid composed of SiO ₂ , MgO, and CaO compounds in an alumina (Al ₂ O ₃₎ powder to form a primary mixture; A second process of adding and mixing a predetermined amount of a binder and an antifoaming agent to the produced primary mixture to generate an alumina slurry; A third process of vacuum degassing for a predetermined time so that the produced alumina slurry has a desired viscosity; A fourth process of sheeting the vacuum degassed alumina slurry by tape casting to produce an alumina green sheet; A fifth process of forming a via hole and an alignment mark via hole in each of the green sheets to correspond to a shape of a target ceramic package; A sixth step of forming an electrode pattern on each of the green sheets through pattern printing using a conductor paste; A seventh process of generating a multilayer ceramic structure by stacking n green sheets generated through the fifth and sixth processes using respective alignment mark via holes; An eighth step of producing a multilayer ceramic sintered body by co-firing the produced multilayer ceramic structure in a baking furnace made of a reducing atmosphere of nitrogen and hydrogen gas; And A method of manufacturing a multilayer ceramic package according to a ninth process of completing a multilayer ceramic package by selectively plating a portion of the multilayer ceramic sintered body with a metal material. The method of claim 1, wherein the alumina powder has an average particle diameter of 2.5 μm. The multilayer according to claim 2, wherein the Talc has an average particle diameter of 6-7 µm and a particle size distribution of 0.2-20 µm, and the clay has an average particle diameter of 1-2 µm and a particle size distribution of 0.2-15 µm. Method for manufacturing ceramics package. The method of claim 1, wherein the weight ratio (A / A + B) of the weight of the sintering aid (A) and the weight of the alumina ball (B) charged to the mixing alumina ball mill is 0.26. 5. The method of claim 4, wherein the alumina ball mill is a 600 L ball mill, and the alumina balls to be loaded are 20 mm in diameter of 240 kg and 30 mm in diameter of 360 kg. The method of claim 1, wherein the plasticizer is polyethylene or butyl benzyl phthalate. The method of claim 1, wherein the binder is an acrylic resin emulsion, and the antifoaming agent is a wax emulsion. 8. The method of claim 1 or 7, wherein the second process is: Adding a predetermined amount of the binder to the produced primary mixture and mixing for a predetermined time: and And adding a defoaming agent of a predetermined capacity to the primary mixture in which the binder is mixed, and then mixing the binder for a predetermined time to produce the alumina slurry. The method of claim 1, wherein the viscosity of the alumina slurry is in the range of 12,000-15,000 cps. 10. The method of claim 9, wherein the vacuum defoaming time is 10-15 minutes, more preferably 12 minutes. The method of claim 1, wherein the thickness of each of the green sheets produced is determined in proportion to the height of the doctor braid for tape casting and inversely proportional to the moving speed of the carrier film. The method for producing a multilayer ceramic package according to claim 1, wherein the shrinkage ratio due to hot press bonding in the reducing atmosphere firing is in the range of 13.8-14.3%. The method for producing a multilayer ceramic package according to claim 1, wherein the water vapor concentration in the reducing atmosphere firing is in the range of 0.040-0.045 g / l. The method of claim 1, wherein the reducing atmosphere firing, nitrogen and hydrogen 8.0, 2.5 m 3 / h-9.0, 2.5 m 3 / h range and the temperature of 1500 to 1600 ℃ manufacturing of a multi-layer ceramic package, characterized in that Way. The method of claim 1, wherein when the reducing atmosphere firing temperature is in the range of 1530-1600 ° C, the humidifier water temperature flowing into the firing furnace has a range of 25-40 ° C. The method of claim 1, wherein the eighth process is a process of performing de-binder firing at a temperature of 800 ° C., nitrogen 1,000-1100 L / h, hydrogen 200-300 L / h, humidifier water temperature 40 ° C. The method of manufacturing a multilayer ceramic package further comprising. The method according to claim 1, wherein in the manufacturing method, the mixing direction of one sheet of green sheet is 15.23-13.6%, the sintered density is 3.42 g / cm3, and the casting direction of two sheets of green sheet is mixed when wet 20-30 hours are mixed. A method of manufacturing a multilayer ceramic package, characterized in that the plastic shrinkage is 16.25-15.84% and the sintered density is 3.43-3.46 g / cm 3. A method for manufacturing a multilayer ceramic package having a structure in which at least two layers are laminated and bonded to a high integrated circuit, A first process of adding and mixing an organic solvent to a sintering aid composed of Talc, CaCO ₃ , Cr ₂ O ₃ , and TiO ₂ compounds to form a primary mixture; A second process of adding and mixing alumina (Al ₂ O ₃ ), a solvent slurry, an organic solvent, an aqueous solvent, a plasticizer, a binder, and a humectant to the produced primary mixture to form an alumina slurry; A third process of vacuum degassing for a predetermined time so that the produced alumina slurry has a desired viscosity; A fourth process of sheeting the vacuum degassed alumina slurry by tape casting to produce an alumina green sheet; A fifth process of forming a via hole and an alignment mark via hole in each of the green sheets to correspond to a shape of a target ceramic package; A sixth step of forming an electrode pattern on each of the green sheets through pattern printing using a conductor paste; A seventh process of generating a multilayer ceramic structure by stacking n green sheets generated through the fifth and sixth processes using respective alignment mark via holes; An eighth step of generating a multilayer ceramic sintered body by simultaneously firing the produced multilayer ceramic structure in a kiln with a reducing atmosphere of nitrogen and hydrogen gas; And A method of manufacturing a multilayer ceramic package according to a ninth process of completing a multilayer ceramic package by selectively plating a portion of the multilayer ceramic sintered body with a metal material. 19. The method of claim 18, wherein the first process is: An eleventh step of mixing the sintering aid into an alumina ball mill loaded with alumina balls having a diameter of 80 mm and a diameter of 30 mm of 120 kg and mixing them for a predetermined time; And And a twelfth step of adding and mixing the organic solvent to the obtained mixture to produce the primary mixture. 20. The method of claim 19, wherein the weight ratio (A / A + B) of the weight of the sintering aid (A) and the weight of the alumina ball (B) charged to the alumina ball mill is 0.245. 19. The method of claim 18, wherein the Talc has a central particle diameter of 16 ± 4.0 ㎛, particle size distribution of 5-20 ㎛, CaCO ₃ has an average particle diameter of 16 ± 4.0 ㎛, particle size distribution of 4-24 ㎛, TiO ₂ The average particle diameter is 0.15-0.25㎛ characterized in that the multilayer ceramic package manufacturing method. 19. The method of claim 18, wherein the second process is: A twenty-first process of adding a predetermined amount of the alumina (Al ₂ O ₃ ) powder, a solvent slurry, a plasticizer, an organic solvent, and an aqueous solvent to the produced primary mixture and mixing the mixture for a predetermined time; A twenty-second process of adding a predetermined amount of the binder and the organic solvent to the mixture and mixing the mixture for a predetermined time; and And a twenty-third step of adding the plasticizer and the organic solvent to the mixture in a predetermined amount and mixing the mixture for a predetermined time to produce the alumina slurry. The alumina powder according to claim 18 or 22, wherein the alumina powder comprises alumina having an average particle diameter of 4 µm and a particle size distribution of 2-44 µm, and an alumina having an average particle diameter of 2.8-3.2 µm and a particle size distribution of 0.6-5 µm. Method for producing a multilayer ceramic package, characterized in that. The method of claim 22, wherein the twenty-first process comprises adding additives into an alumina ball mill loaded with alumina balls having a diameter of 30 mm of 700 kg and a diameter of 60 mm of 300 kg and mixing them for a predetermined time. 25. The method of claim 24, wherein the weight ratio (A / A + B) of the weight of the primary mixture + additive (A) and the weight of the alumina ball (B) charged to the alumina ball mill is 0.377. . 23. The method of claim 22, wherein the plasticizer used in the twenty-first step is dibutyl glycolate (DBP) and polyethylene glycol (PEG). The method for manufacturing a multilayer ceramic package according to claim 22, wherein said binder is BL-1z. 23. The method of claim 22, wherein the plasticizer used in the twenty-third step is dibutyl glycolate (DBP). 19. The method of claim 18, wherein the viscosity of the alumina slurry is in the range of 12,000-15,000 cps. 30. The method of claim 29, wherein the vacuum defoaming time is 10-15 minutes, more preferably 12 minutes. 19. The method of claim 18, wherein the thickness of each green sheet produced is determined in proportion to the height of the doctor braid for tape casting and inversely proportional to the moving speed of the carrier film. 19. The method of manufacturing a multilayer ceramic package according to claim 18, wherein the shrinkage ratio due to hot press bonding in the reducing atmosphere firing is in the range of 13.8-14.3%. The method for producing a multilayer ceramic package according to claim 18, wherein the water vapor concentration in the reducing atmosphere firing is in the range of 0.040-0.045. 19. The method of claim 18, wherein the reducing atmosphere firing, nitrogen and hydrogen 8.0, 2.5 m 3 / h-9.0, 2.5 m 3 / h range and the temperature of 1500 to 1600 ℃ manufacturing of a multi-layer ceramic package, characterized in that Way. 19. The method of claim 18, wherein when the reducing atmosphere firing temperature is in the range of 1530-1600 ° C, the humidifier water temperature flowing into the firing furnace has a range of 25-40 ° C. 19. The method of claim 18, wherein the eighth process is a process of performing debinder firing at a temperature of 800 ° C, nitrogen 1,000-1100 L / h, hydrogen 200-300 L / h, humidifier water temperature 40 ° C. The method of manufacturing a multilayer ceramic package further comprising. 19. The method according to claim 18, wherein, in a wet 20-30 hour mixing, the casting direction of one green sheet has a casting shrinkage of 15.23-13.6%, a sintered density of 3.42 g / cm 3, and the casting direction of two green sheets. A method of manufacturing a multilayer ceramic package, characterized in that the plastic shrinkage is 16.25-15.84% and the sintered density is 3.43-3.46 g / cm 3. A method for manufacturing a multilayer ceramic package having a structure in which at least two layers are laminated and bonded to a high integrated circuit, A first step of adding and mixing a mixed organic solvent containing a plurality of organic solvents to a sintering aid composed of Talc, CaCO ₃ , Cr ₂ O ₃ , and TiO ₂ compounds to form a primary mixture; A second process of adding and mixing alumina (Al ₂ O ₃ ) and a plasticizer to the resulting primary mixture to produce a secondary mixture as a secondary mixture; A third process of adding and mixing a binder to the produced secondary mixture to generate an alumina slurry; A fourth process of vacuum degassing for a predetermined time so that the produced alumina slurry has a desired viscosity; A fifth process of sheeting the vacuum degassed alumina slurry by tape casting to produce an alumina green sheet; A sixth step of forming a via hole and an alignment mark via hole in each of the green sheets to correspond to a shape of a target ceramic package; A seventh step of forming an electrode pattern on each of the green sheets through pattern printing using a conductor paste; An eighth process of stacking n green sheets generated through the sixth and seventh processes using each alignment mark via hole to generate a multilayer ceramic structure; A ninth step of generating a multilayer ceramic sintered body by simultaneously firing the produced multilayer ceramic structure in a kiln with a reducing atmosphere of nitrogen and hydrogen gas; And A method of manufacturing a multilayer ceramic package according to a tenth step of completing a multilayer ceramic package by selectively plating a portion of the produced multilayer ceramic sintered body with a metal material. 39. The method of claim 38, wherein the Talc has a central particle size of 16 ± 4.0 ㎛, particle size distribution of 5-20 ㎛, CaCO ₃ has an average particle diameter of 16 ± 4.0 ㎛, particle size distribution of 4-24 ㎛, TiO ₂ The average particle diameter is 0.15-0.25㎛ characterized in that the multilayer ceramic package manufacturing method. The method of claim 38, wherein the mixed organic solvent comprises an aromatic solvent, an alcohol solvent and a ketone solvent. 41. The method of claim 40, wherein the mixed weight ratio of the aromatic solvent, alcohol solvent, and ketone solvent has a range of 2.0: 0.7: 1.3-4.0: 1.4: 2.6. 42. The method of claim 40 or 41, wherein the aromatic solvent is toluene or xylene, the alcohol solvent is ethyl alcohol, isopropyl alcohol and butyl alcohol, and the ketone solvent is methyl ethyl ketone (MEK) or MIBK. Method for producing a multilayer ceramic package, characterized in that. The method according to claim 38, wherein the primary mixture is produced by mixing the sintering aid and the mixed organic solvent in an alumina ball mill loaded with an alumina ball having a diameter of 30 mm of 7000 kg and a diameter of 60 mm of 300 kg. Method for manufacturing multilayer ceramics package. 39. The alumina of claim 38, wherein the alumina comprises alumina having an average particle diameter of 4 µm and a particle size distribution of 2-44 µm and an alumina having an average particle diameter of 2.8-3.2 µm and a particle size distribution of 0.6-5 µm. Method for manufacturing multilayer ceramics package. 39. The method of claim 38, wherein said plasticizer is polyethylene glycol (PEG) and dibutel glycolate (DBP). The method for manufacturing a multilayer ceramic package according to claim 38, wherein the binder is BL-1z and BM-Sz. The method of claim 38, wherein the viscosity of the alumina slurry is in the range of 12,000-13,000 cps. 48. The method of claim 47, wherein the vacuum defoaming time is 10-15 minutes, more preferably 12 minutes. 39. The method of claim 38, wherein the thickness of each green sheet produced is determined in proportion to the height of the doctor braid following the tape casting and inversely proportional to the moving speed of the carrier film. The method for manufacturing a multilayer ceramic package according to claim 38, wherein the shrinkage ratio due to hot press bonding in the reducing atmosphere firing is in the range of 13.8-14.3%. The method for producing a multilayer ceramic package according to claim 38, wherein the water vapor concentration in the reducing atmosphere firing is in the range of 0.040-0.045 g / l. 39. The method of claim 38, wherein the reducing atmosphere firing, nitrogen and hydrogen 8.0, 2.5 m 3 / h-9.0, 2.5 m 3 / h range and the temperature of 1550-1600 ℃ manufacturing of a multilayer ceramic package, characterized in that Way. 39. The method of claim 38, wherein when the reducing atmosphere firing temperature is in the range of 1530-1600 ° C, the humidifier water temperature flowing into the firing furnace has a range of 25-40 ° C. 39. The method of claim 38, wherein the eighth process is a process of performing de-binder firing at a temperature of 800 ° C., nitrogen 1,000-1100 L / h, hydrogen 200-300 L / h, humidifier water temperature 40 ° C. Multi-layer ceramics package manufacturing method comprising a. 39. The method according to claim 38, wherein in the manufacturing method, when the wet 20-30 hours are mixed, the casting direction of one green sheet has a plastic shrinkage rate of 15.23-13.6%, a sintered density of 3.42 g / cm 3, and the casting direction of two green sheets. A method of manufacturing a multilayer ceramic package, characterized in that the plastic shrinkage is 16.25-15.84% and the sintered density is 3.43-3.46 g / cm 3.