JPH07105598B2 - Multilayer substrate stacking method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Outline] The present invention relates to a method for laminating a multi-layered substrate formed by laminating a plurality of green sheets, for the purpose of improving the efficiency and reliability of the substrate laminating process. The temperature of the hot plates arranged in a sandwiched manner is set to a temperature for rapid heating that is higher than the standard lamination temperature, and the pressing force of the hot plates is set to a heat transfer pressure that is lower than the standard lamination pressure. Then, the hot plate is once separated from the mold to lower its temperature to the standard stacking temperature, and the pressing force of the hot plate is set to the standard stacking pressure to carry out the second stacking process. Is carried out.

[Industrial application field]

The present invention relates to a method for laminating a multi-layer substrate formed by laminating a plurality of green sheets.

[Prior Art] FIG. 2 is a schematic perspective view showing a structure of a multilayer substrate (hereinafter referred to as a work), FIG. 3 is a schematic view showing an example of a work stacking process, and FIG. 4 is heat in a work stacking process. It is a graph which shows the effect | action of a board.

As shown in FIG. 2, this work 10 composed of a plurality of green sheets 1 has a structure in which the green sheets 1 are sequentially laminated and the green sheets 1 are adhered to each other by heating while pressing the green sheets 1 in the direction of the arrow. Completed as an independent work 10. FIG. 3 is a schematic view showing an example of the stacking process of the works. 8 is a mold including an upper mold 8a and a lower mold 8b, and 5 is a pair of molds arranged to sandwich the mold 8 from above and below. A hot plate, 15 is a temperature control device for controlling the temperature of the hot plate 5, and 20 is a pressing force control device for controlling the pressing force of the hot plate 5.

The manufacturing process of the work 10 will be described below (see FIG. 3).

． First, a plurality of green sheets 1 are housed in a stacked manner between the upper die 8a and the lower die 8b of the die 8.

． The mold 8 is moved up and down (arrow F-
Press from the F'direction). When the mold 8 is pressed, the green sheet 1 housed in the mold 8
Are in pressure contact with each other. The pressing force at this time is controlled by the pressing force control device 20.

． The temperature of the hot plate 5 is raised with the mold 8 being pressed from both sides, and the mold 8 is heated. By continuing the heating for a predetermined time, these green sheets 1 are joined to each other to form an independent work 10. The temperature of the hot plate 5 at this time is controlled by the temperature controller 15.

FIG. 4 is a graph showing the action of the heating plate 5 in the work stacking process. In the conventional stacking process, the pressing force of the heating plate 5 and the stacking temperature are always constant throughout the process (pressing force is They were controlled so as to keep the standard laminating pressure P≈500 kg / cm ² and the laminating temperature T−180 ° C., respectively. In the figure, K is the time required for the laminating process (hereinafter referred to as laminating required time), P is the standard laminating pressure, T is the standard laminating temperature, A is the laminating start point, and B is the laminating start point.
Is the standard lamination temperature reaching point of the hot plate, C is the heating end point of the hot plate,
D is the end point of the lamination process, α is the temperature profile of the hot plate, β
Shows the pressure profile of the hot plate, respectively.

[Problems to be Solved by the Invention]

In this conventional method, as shown in FIG. 4, since the temperature of the hot plate 5 is controlled while the mold 8 and the hot plate 5 are in contact with each other, the thermal mass is large, and therefore the work 10 Phenomenon in which the temperature of the workpiece 10 is difficult to maintain and the temperature of the workpiece 10 goes into a runaway state (a phenomenon in which the temperature fluctuates abnormally)
Was frequently occurring. In particular, when the temperature of the work 10 rises too much, the binder contained in the green sheets evaporates and disappears, so that the adhesive force between the green sheets 1 is reduced and peeling is facilitated, and the green sheets themselves are fragile. Become.

The present invention has been made to solve this problem, and divides the laminating step into the primary and secondary steps, and performs the laminating by changing the heating conditions and pressurizing conditions of the work 10 in the primary step and the secondary step, respectively. It is configured.

[Means for Solving the Problems]

As shown in FIG. 1, the method for laminating a multi-layer substrate according to the present invention is such that the temperature of the hot plate 5 arranged so as to sandwich the work 10 from the outside of the die 8 is higher than the standard laminating temperature T for rapid heating. ₁ is set and the pressure of the hot plate 5 is set to a heat transfer pressure P ₁ lower than the standard laminating pressure P to carry out the first laminating step, and the temperature of the work 10 reaches a predetermined temperature. At this time, the hot plate 5 is once separated from the mold 8 to lower the temperature to the standard laminating temperature T, and the pressing force of the hot plate 5 is set to the standard laminating pressure P to carry out the second laminating step. The work 10 is laminated by carrying out the work.

[Action]

According to the present invention, the temperature of the hot plate 5 is set to a temperature higher than the standard stacking temperature T, that is, the temperature T ₁ for rapid heating, and the first stacking step is first carried out. Since the temperature of the hot plate 5 is set to the standard laminating temperature T again from the mold 8 and the second laminating process is performed, the work
Since the temperature runaway phenomenon in which the temperature of 10 abnormally rises does not occur, the quality of the work is stabilized and the stacking process of the works is significantly improved.

〔Example〕

 The present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a diagram showing an embodiment of a method for laminating a multi-layer substrate according to the present invention, in which the same parts as those in FIGS. 2, 3 and 4 are designated by the same reference numerals.

As shown in FIG. 1, in the method for laminating a multi-layer substrate according to the present invention, the temperature of the hot plate 5 arranged so as to sandwich the work 10 from the outside of the die 8 is higher than the standard laminating temperature T for rapid heating. T ₁ (≈2T) is set, and the pressure applied to the hot plate 5, that is, the force in the arrow F direction and the arrow F ′ direction shown in FIG. 3 is lower than the standard lamination pressure P, the heat transfer pressure P ₁ ( When the temperature of the work 10 reaches a predetermined temperature, that is, a temperature slightly lower than the standard temperature, as shown by the thermal profile γ of the work 10, when the first stacking process is performed under the setting of 50 kg / cm ² or less). Then, the hot plate 5 is once separated from the mold 8 to lower the hot plate temperature to the standard laminating temperature T, and the pressing force of the hot plate 5 is reset to the standard laminating pressure P to carry out the second laminating step. It has a two-stage laminated structure for carrying out. In the figure, B ₁ is the standard lamination temperature point of the hot plate, C ₁ heating end point of the heating plate in the primary step, D ₁
Is the standard lamination temperature reaching point of the hot plate in the secondary process, D ₂ is the heating end point of the hot plate in the secondary process, D ₃ is the end point of the secondary process, α ₁ is the temperature profile of the hot plate, β ₁ is the pressure profile of the hot plate, and K ₁ is the time required for lamination.

In this method, the temperature of the hot plate 5 is set to the rapid heating temperature T ₁ higher than the standard stacking temperature T and the first stacking is performed. Therefore, the time until the workpiece 10 reaches the predetermined stacking temperature is set. It is efficient because it is short. In addition, in this stacking method, once the temperature of the work 10 reaches a predetermined stacking temperature, the hot plate 5 is temporarily cooled.
Is separated from the mold 8 and when the temperature of the hot plate 5 drops to the standard laminating temperature T, the hot plate 5 is brought into contact with the mold 8 again to heat the work 10. The temperature never rises too much.

Further, according to this stacking method, the heat transfer pressure of the heat plate 5 is smaller than the standard stacking pressure P until the work 10 reaches a predetermined temperature (this heat transfer pressure only transfers the heat of the heat plate 5 to each green sheet 1). Since it is configured to press with P ₁ , there is no risk that the internal structure of the work 10 before lamination will change due to this pressure. In addition,
In this laminating method, the work 10 is pressed with the standard laminating pressure P in the secondary laminating step of joining the green sheets 1, so that the reliability regarding the adhesive strength between the green sheets 1 is sufficiently ensured. .

In this stacking method, since the first stacking step is performed at the rapid heating temperature T ₁ higher than the standard stacking temperature T, the time until the green sheet 1 reaches the predetermined temperature can be shortened. The required lamination time K ₁ is shorter than the conventional required lamination time K (see FIG. 4).

〔The invention's effect〕

As is clear from the above description, the lamination method according to the present invention has no temperature runaway of the green sheet during lamination, so that the work quality is remarkably stable, and the time until the green sheet reaches the predetermined temperature is high. Due to the short length, the lamination process is significantly efficient.

[Brief description of drawings]

FIG. 1 is a graph showing an embodiment of the work stacking method according to the present invention, FIG. 2 is a schematic perspective view showing the structure of the work, FIG. 3 is a schematic view showing an example of the work stacking process, and FIG. [Fig. 4] is a graph showing an action of a hot plate in a work stacking process. In the figure, 1 is a green sheet, 5 is a hot plate, 8 is a mold, 8a is an upper mold, 8b is a lower mold, 10 is a work (multilayer substrate), 15
Is a temperature control device, 20 is a pressing force control device, P is a standard laminating pressure, P ₁ is a heat transfer pressure, T is a standard laminating temperature, T ₁ is a rapid heating temperature, K and K ₁ are laminating process required time, Are shown respectively.

Claims (1)

[Claims] 1. A method for laminating a multi-layer substrate (10), which comprises laminating a plurality of green sheets (1), wherein the multi-layer substrate (10) is arranged so as to be sandwiched from the outside of a mold (8). The temperature of the heated hot plate (5) is set to a temperature for rapid heating (T ₁ ) higher than the standard stacking temperature (T), and the pressing force of the hot plate (5) is lower than the standard stacking pressure (P). The heat transfer pressure (P ₁ ) is set and the first laminating step is carried out. Then, the hot plate (5) is once separated from the mold (8) and the temperature reaches the standard laminating temperature (T). A method for laminating a multi-layer substrate, which comprises lowering the pressure of the hot plate (5) to the standard laminating pressure (P) and performing the second laminating step.