JPH085052B2 - Method for manufacturing ceramic laminate - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is, for example, an IC laminator.
The present invention relates to a method for laminating a ceramics laminated body formed by laminating and pressing a plurality of green tapes such as a top package.

[0002]

2. Description of the Related Art Conventionally, IC laminate packages are
Multiple grees created by doctor blade method, etc.
Each of the tapes is formed into a predetermined shape, metallized wiring is provided on the surface of the tapes if necessary, and the green tapes are laminated and hot pressed, and then baked in a humidified hydrogen gas. It is created by the procedure.

By the way, when a green sheet is laminated and pressure-bonded when a ceramic laminate of this type is formed, conventionally, a plurality of green sheets are laminated by air or an oil press. The pressure is applied to the joint to bond the joint.

[0004]

However, when the green sheets are laminated and pressure-bonded by pressing as described above, if the shape of the laminated body becomes complicated, pressure must be applied using a jig corresponding to the shape. There was a problem that the laminated body was deformed when pressure was applied, and the workability was poor. Further, when crimping a laminated body having a complicated shape, it is necessary to create and use a jig having high dimensional accuracy, and many jigs corresponding to individual shapes are required. Further, since the press is flat, only a small amount can be joined at one time, which is not suitable for mass production.

According to the present invention, when the above-mentioned laminated body is pressed and joined, it can be joined by a simple operation without using a jig, and a large amount of different shapes can be joined at the same time. The present invention was made for the purpose of providing a method for laminating a laminate, and the object was achieved by the following method.

[0006]

[Means for Solving the Problems] That is, the method of the present invention for solving the above-mentioned problems is such that, when a plurality of green tapes containing ceramics as a main component and formed in a predetermined shape are laminated and joined by pressing, After stacking a plurality of green tapes and temporarily adhering them with a solvent, protect the surroundings in an airtight manner and press-bond the joints in a liquid of a predetermined pressure in the temperature range of 40 ° C to 80 ° C. The gist is a method of manufacturing a characteristic ceramics laminate.

Here, as is known in the art, the green tape is a ceramic raw material powder such as alumina, forsterite, cordierite, etc. in which a thermoplastic resin, a plasticizer and the like are dissolved in an organic solvent. Is dispersed and the solution is made to flow on a flat plate to a uniform thickness to evaporate the solvent, for example, a doctor blade method or the like. The green tape thus formed is formed into a predetermined shape, and if necessary, a metal paste containing powder of tungsten, molybdenum or the like as a main component is metallized by screen printing.

Next, in the present invention, a plurality of green tapes formed as described above are laminated and then pressure-bonded in a liquid of water or oil of a predetermined pressure. Temporarily bond the joints with a solvent to prevent misalignment. In addition, it is necessary to protect the laminated body when it is put into the liquid. For this purpose, the laminated body is put in a bag made of a thin film such as polyethylene and vacuumed or sealed by a resin film or the like. It is possible to cover it. When a resin film is used for this protective film, it is necessary to peel off the protective film after pressure-bonding the laminated body, so it is desirable to use a resin film that can be easily peeled off.

[0009] In yet a laminated green tape as described above, the thermoplastic resin to the in the green tape bonding between 40 ° C. to 80 ° C. the heat softened flow, Ru Kotogaa such layers are easily integrated. Therefore, pressurizing liquid above the temperature
It is heated to a range of degrees.

[0010]

As described above, in the present invention, the laminated green
When the press-bonding is carried out, it is carried out in a liquid having a predetermined pressure. Therefore, it is not necessary to individually prepare a jig for breathing as in the conventional case, and simply protect it in a hermetically sealed manner with a bag made of polyethylene or the like.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the method of the present invention is applied to the production of a laminated package for an IC will be described with reference to the drawings. FIG. 1 is a flow chart showing the manufacturing process of the laminate package of this embodiment.

As shown in the figure, first, in step P1, raw materials are mixed. For this, for example, Si as an additive
A binder such as polyvinyl butyral is added to 90% or more alumina ceramic powder to which O ₂ , MgO, CaO or the like is added, and the mixture is added to an organic solvent such as toluene or methanol by using a ball mill or the like. Mixing to form a slurry is performed.

When the raw materials are prepared, the next step P2
Then, a green tape having a thickness of, for example, 600 .mu. Is prepared from the blended raw materials by a doctor blade method or the like, and the green tape is punched into a predetermined shape in the next step P3. .

The grease formed into a predetermined shape in step P3
In step P4, a metal paste mainly containing tungsten or the like is printed on the tape by a screen printing method using a predetermined mask, and metallized wiring is provided.

In the subsequent step P5, the layers (bottom layer A, die attach layer B, bonding pad layer C, and bonding pad layer C shown in FIG. 2) constituting the laminate package formed in the above steps P3 and P4, respectively, are formed. -Align the layer D) and provisionally bond with solvent.

Laminated body 10 of green tape temporarily adhered
In step P6, as shown in FIG. 2, it is placed in a thin film bag 12 made of polyethylene or the like having a thickness of about 100 μm and vacuum packed. And this vacuum-packed laminated body 1
0 is the pressurizing device 1 as shown in FIG.
The pressure is adjusted to a predetermined pressure (for example, 100 Kg / cm ² ) by means of No. 4 and left in the underwater press tank 16 using water as a pressure medium for 2 minutes for pressure bonding.

Thereafter, in step P8, the pressure-bonded laminated body 10 is taken out from the bag 12 vacuum-packed in step P6, cut into a predetermined size and fired in the next step P9. At this time, before firing, metallization printing is applied to the side surface, if necessary.

When the ceramic laminated body is thus fired, the process proceeds to step P10, where the metallized portion of the tungsten exposed in the atmosphere is plated with nickel to prevent oxidation, and in the next step P11 terminals and leads are formed. The wire is brazed with Ag / Cu eutectic silver solder or the like. Thereafter, in step P12, the above-mentioned parts are plated with gold to complete the laminate package.

The laminated package thus prepared is used in the cavity portion in which the IC is mounted, that is, in FIG.
The space formed by the bonding pad layer C and the frame layer D on the die attach layer B shown in FIG. 2 was evacuated, and an airtightness test was conducted by supplying helium gas from the outside. ^-2
[Cc. ] The following standards were fully cleared. (Zero defects in 2000).

As described above, in this embodiment, the laminated green tape laminate 10 is formed into the underwater press tank 16
Pressure is applied inside and pressure is applied. Therefore, as in the prior art, the lamination and pressure bonding of the green tape can be easily performed without using a jig, and since it is only necessary to put it in water, if a large press tank is used, a large amount of mass can be obtained. It becomes possible to press-bond the laminate at the same time.

Although the water temperature of the underwater press tank is not mentioned in the above description, pressure bonding can be performed at room temperature, but the process can be further improved by heating at about 40 ° C. to 80 ° C., for example. It can be processed quickly. Although water was used for the press tank, oil can also be used. Differences in effects depending on the presence or absence of heating during bonding are shown in FIGS. 4 and 5. In all of these figures, the pressure at the time of adhesion is 40 kg / cm ² , the pressurizing time is 1 minute, and the room temperature to
FIG. 4 shows the results of observing 20 samples at various temperatures of 100 ° C., FIG. 4 shows the leak occurrence rate between layers of the green tape, and FIG. 5 shows the bubble occurrence rate of the green tape laminate.

From FIGS. 4 and 5, the temperature at the time of bonding is 40 ° C.
If it does not meet the requirements, the adhesiveness will be poor and leakage will occur.
When the temperature exceeds 0 ° C, the residual solvent in the green tape or the solvent for temporary adhesion is gasified to cause a vacancy phenomenon in the laminate, whereas if the bonding is performed in the range of 40 ° C to 80 ° C, such a defect may occur. It turns out that it does not occur.

As described in detail above, the method for producing a ceramics laminate of the present invention is characterized in that when the laminated green tapes are bonded by pressure, they are pressure-bonded in a liquid of a predetermined pressure. There is. In other words, there is no need to press with a jig as in the past, but simply by covering the surface in an airtight manner and putting it in the liquid, the laminated green tape can be easily pressure-bonded. It becomes.

Therefore, needless to say, a jig formed in a predetermined shape is unnecessary, and pressure bonding can be performed simultaneously regardless of the shape of the laminated body, which facilitates mass production. Further, in the case of the conventional press working, it is necessary to strictly control the parallelism and the like of the working plate, but since the present invention is pressurization in a liquid, the management of the device becomes simple. Further, when the laminated body is heated during pressurization, it can be easily executed by raising the liquid temperature.

[Brief description of drawings]

FIG. 1 is a flow chart showing an example of an embodiment in which the method of the present invention is applied to the manufacture of a laminated package of ICs, and the manufacturing process thereof.

FIG. 2 is a cross-sectional view of a vacuum-packed green tape laminate manufactured during the above process.

FIG. 3 is an explanatory diagram illustrating a pressing method for a laminated body.

FIG. 4 is a graph showing a relationship between a temperature and a leak occurrence rate during pressure bonding.

FIG. 5 is a graph showing the relationship between temperature and bubble generation rate during pressure bonding.

[Explanation of symbols]

 10 Laminated body 12 Bag 14 Pressurizing device 16 Underwater press tank

Claims (1)

[Claims] 1. When laminating a plurality of green tapes, each of which has a ceramics as a main component and formed into a predetermined shape, and press-bonding the plurality of green tapes, the plurality of green tapes are laminated and temporarily adhered with a solvent, and then the surroundings. Airtightly protect the joint at 40 ° C-8
A method for producing a ceramics laminate, which comprises pressure bonding in a liquid having a predetermined pressure within a temperature range of 0 ° C.