JPS61215021A - Manufacture of mutilayer printed circuit board and its manufacturing device - Google Patents

Abstract

PURPOSE:To obtain a multilayer printed circuit board with stabilized high-quality, by a method wherein a temperature rise and heating of a hot press are performed by a separate heat source after the same has been heated through steam, which is cooled through the steam after that and cooled further by making use of the steam and cooling water jointly. CONSTITUTION:A tube course wherein steam and water flow commonly is formed within a pair of a top and bottom hot platens 2, 3, which are provided with a built-in electric heater controlled by an adjusting device. A plurality of sheets of inner layer bases unified through an insulating adhesive layer are heated and pressurized between the hot platens 2, 3, laminated and stuck according to an established pressure pattern and temperature pattern after they have been carried in on the hot platen 3. The temperature is risen up to a preset one t1 deg.C through steam heating while an opening of a steam inlet valve 10 is being controlled after that, and at the time of cooling after holding for a fixed period of time at a preset temperature t2 deg.C through electric heater heating, the steam is streamed for the fixed period of time based on a preset value and then cooling is perform by making use of the steam and cooling water jointly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method for manufacturing a multilayer printed wiring board and an apparatus for manufacturing the same, and more particularly to a method for multilayer molding suitable for lamination bonding of printed wiring boards, and an apparatus and apparatus for the same. .
1.1 [Background of the Invention] As a conventional cooling method in the lamination bonding process of multilayer printed wiring boards, for example, as shown in Japanese Patent Laid-Open No. 56-58299, the cooling water supply valve is fully opened during cooling, and the cooling water is A known method is to intermittently open and close a supply solenoid valve to intermittently supply cooling water for cooling a hot press, thereby slowing down the temperature drop rate. This method was effective in reducing the amount of dimensional expansion and contraction of multilayer printed wiring boards.However, since this method does not quantitatively control the cooling rate, it is possible to cool at an arbitrary cooling rate. It is not possible. That is, the temperature drop rate increases while the cooling water is flowing, and the temperature decrease rate decreases while the cooling water is not flowing, making it difficult to obtain a constant temperature drop rate. There is also the problem that the rate of temperature drop changes depending on changes in the temperature of the cooling water. This cooling rate is due to the warpage of the multilayer printed wiring board,
This has a subtle effect on the amount of torsion, amount of dimensional expansion and contraction, and internal residual stress, so if the cooling rate changes for each multilayer printed board to be bonded, the amount of warpage, amount of twist, amount of dimensional expansion and contraction, and internal residual stress will also change, which is a problem for quality control. That was a problem.

In addition, using only cooling water as a cooling medium is suitable for hot presses where the heating medium is steam and the heating temperature is, for example, about 170°C maximum, but using other heating media, such as an electric heater, is suitable. Heating temperature up to 300'C
Regarding hot presses that reduce heat to a certain degree, large amounts of water were generated in the pipes and the pipe paths inside the heating plate during the early stage of cooling, which was a safety problem.

[Purpose of the invention]

An object of the present invention is to provide a multilayer molding method for a multilayer printed wiring board and an apparatus for manufacturing the same, which solves the problems in quality control of multilayer printed wiring boards and the safety problems of the equipment in the conventional methods. be.

[Summary of the invention]

In the present invention, after heating the hot press with steam, the temperature is further heated using another heating source, and then...

The present invention is characterized by a method for manufacturing a multilayer printed wiring board that is cooled by steam and then cooled by using steam and cooling water in combination.

The present invention also provides a means for heating the hot press with steam, another heating means for further heating the hot press, a means for cooling the hot press with cooling water, and a means for heating the hot press with steam while detecting the temperature of the hot platen of the hot press. The present invention is characterized by an apparatus for manufacturing a multilayer printed wiring board, which includes means for controlling the heating plate to be heated by the above-mentioned heating means, then cooled by steam, and then cooled by using both steam and cooling water.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the heating and cooling mechanism, and represents the piping routes for steam, water and air, and the arrangement of valves. FIG. 2 shows the steam control mechanism. FIG. 3 shows the cooling water control mechanism. Figure 4 shows a model of the set temperature pattern for laminating and bonding a hot press containing multilayer printed wiring boards while controlling the temperature, and the corresponding control of the heating and cooling mechanism (opening/closing of each valve, electric heater, etc.). The on/off time chart is shown below.

In FIG. 1, numeral 1 is a hot press, and numeral 2.3 is a pair of upper and lower heating plates (generally there are a plurality of sets, but one set is shown as an example). A pipe path is formed in the hot platen 2.3 through which steam and water commonly flow. Further, an electric heater controlled by a regulator (not shown) is built into the heating plate. The plurality of inner-layer substrates integrated via an insulating adhesive layer are carried onto the heating platen 3, and then pushed up by the action of a hydraulic device (not shown) to create a set pressure cover turn and temperature pattern. According to the above, heat and pressure are applied between the hot platens 2 and 6, and the layers are laminated and bonded.

Next, the opening/closing control of each valve will be explained with reference to FIG. 1 as well. 37 is a dry air source (for example, 5 KJI/
cllG air supply source), and the dry air passes through the stop valve 38 and the filter 69° to the pressure reducing valve 4.
After the pressure is reduced to, for example, 3.5'r/iG at 0, it is supplied to each electromagnetic valve 16, 17, 1B, 19, 20 and 21. 41 is a pressure gauge. 22 is a silencer.

Each solenoid valve is on/off controlled by sequence control, and when the solenoid valve 16 is on, the diaphragm valve (hereinafter referred to as steam population valve 10) is connected to the diaphragm valve (hereinafter referred to as steam population valve 10) through the electropneumatic positioner 26 when the solenoid valve 16 is on, and when the solenoid valve 17 is on, the electric power is When the solenoid valve 18 is on, the diaphragm valve (hereinafter referred to as the cooling water valve 12) is connected to the diaphragm valve (hereinafter referred to as the cooling water valve 12) through the empty positioner 24.
3), when the solenoid valve 19 is on, the diaphragm valve (hereinafter referred to as the blow outlet valve 14), and when the solenoid valve 20 is on, the diaphragm valve (hereinafter referred to as the drain outlet valve 15).
Supply dry air to each. Here, the diaphragm valve refers to a flow control valve operated by air pressure. An electro-pneumatic positioner is a mechanism that is attached to a diaphragm valve and uses a signal current from an indicating controller (described later) to operate a built-in pneumatic pilot pulp to adjust the supplied dry air pressure and supply it to the diaphragm valve. can be,
This is a device that controls the movement of the diaphragm valve and the flow rate of dry air.

Next, the paths through which steam and cooling water flow will be explained with reference to FIG. For example, 9V4f/dG, 175
Steam at 0.degree. C. enters from the steam inlet shown, passes through the stop valve 25, the strainer 26 and the steam manifold valve 10, and flows into the header 4. The steam then flows into each hot platen 2.5 so as to be evenly distributed. In the example shown in FIG. 1, one stream of steam flows from the header 4 through the stop valve 6 and through the pipe path inside the heating platen 2 to exchange heat, and
flows into header 5 through. The other stream of steam flows from the header 4 through the stop valve 7 through the pipe path in the hot platen 3 for heat exchange, and then flows through the stop valve 9 into the header 5. When the temperature of the hot platen is lower than the steam temperature, the steam becomes condensed water due to heat exchange. The steam collected in the header 5 flows out, passes through the strainer 1° 32, and passes through the blow throttle valve 13, the blow outlet valve 14, or the drain outlet valve 15, which are opened under sequence control.

The steam passing through the blow throttle valve 1'5 flows through the throttle valve 33 towards the blow outlet shown. Also, the blow outlet valve 14
The steam thus passed flows through the stop valve 34 towards the blow outlet shown. Further, the steam that has passed through the drain outlet valve 15 passes through a steam trap 66, becomes condensed water, and flows through the stop valve 55 toward the illustrated drain outlet.

For example, 4 Ky f/r, tl O120cC cooling water &'! The cooling water enters from the illustrated cooling water inlet and flows into the header 5 through the stop valve 30, the strainer 61, and the cooling water artificial valve 12. And the cooling water is for each heating plate 2,
Cool them by evenly distributing them into the filter.

In the example shown in FIG. 1, the steam flows through the hot platen 2.3 in a path completely opposite to the flow of steam described above, undergoes heat conversion, and then flows into the header 4. The cooling water collected in the header 4 flows out to the strainer 29, the cooling water outlet valve 11 and the stop valve 2.
8 and flows toward the cooling water outlet shown in Figure 1.

The reason why the steam is allowed to flow from the header 4 to the header 5 is to quickly discharge condensed water generated as a result of heat exchange by the action of gravity. The reason why the cooling water flows from the header 5 toward the header 41C is to sufficiently fill the pipe path with cooling water and to perform heat exchange evenly from the inner surface of the pipe.

Next, the steam control mechanism will be explained with reference to FIG.

101 has the set temperature pattern input in advance.
6゜103 is a personal converter that commands the set temperature pattern during operation. Potentiometer 07 for high temperature.
and a potentiometer converter for steam heating of the potentiometer 108 for low temperatures, which generates a constant signal current.

The automatic operation of the personal computer 01 and the operation using the potentiometer converter 106 for steam heating are selected by a changeover switch.

106 is a thermocouple that detects the temperature of the heating plate 2. Note that the temperature of the heating platen 3 may be detected instead of the heating platen 2. 102
is a steam indicating controller that compares the temperature commanded from the personal computer 01 or the steam heating potentiometer 10 with the temperature detected by the thermocouple 106, and sends a signal current to the electropneumatic positioner 26 by PiD control. be. 104 is a potentiometer converter for steam cooling of the potentiometer 09 for steam cooling temperature setting, and sends a constant signal current to the electropneumatic positioner 25 during steam cooling. The electropneumatic positioner 25 is based on the signal current of the steam indicating controller 102 or the potentiometer converter 104 for steam cooling.
The movement of the steam valve 10 shown in FIG. 1 is controlled.

Next, the cooling water control mechanism will be explained with reference to FIG. A thermocouple 113 detects the temperature of the heating plate 3. In addition, the temperature of heating plate 2 is in the range V of heating plate 6.

The degree may also be detected. 110 compares the temperature commanded from the personal converter 101 and the temperature detected by the thermocouple 113, P1. This is a cooling water indicating controller that sends a signal current to the electro-pneumatic positioner 24 under D control. 111
is a potentiometer converter next to the potentiometer 114 for setting the amount of cooling water 1, and sends a constant signal current to the electropneumatic positioner 24 when the hot platen is cooled by the cooling water.

The electro-pneumatic positioner 24 is a cooling water indicating controller 110 or a cooling water potentiometer exchanger.

Based on the signal current 111, the movement of the cooling water artificial valve 12 shown in FIG. 1 is controlled.

Next, Figure 4 shows a model of the set temperature pattern when laminating and bonding multilayer printed wiring boards while controlling the temperature using a hot press, and a corresponding control method for the heating and cooling mechanism (opening/closing each valve, turning on/off the electric heater). ) will be explained. FIG. 4 (at shows a model of a set temperature pattern with temperature on the vertical axis and time on the horizontal axis.

Furthermore, sections are provided over time, and heating and cooling methods in each section j are shown.

FIG. 4 1al corresponds to the time course of FIG. 4 1al,
It shows the opening/closing of each valve and the on/off control of the electric heater as time passes and the interval changes. 1. First, the steam population valve 10 and the drain outlet valve 15 are fully opened and initial blowing is performed for 10 seconds, and the residual water in the hot plate is pushed away by steam f, and then the opening degree of the steam population valve 10 is controlled. Steam heating is performed while the steam temperature is set at t. After raising the temperature to c, a constant temperature is maintained. While performing steam heating, the blow outlet valve 14 is closed at 30°C.
A new steam heating plate that opens fully for 2 seconds once every second 2.3
At the same time as the blow outlet valve 14 opens, the drain outlet valve 15 is closed for 2.5 seconds, and the steam or condensed water that comes out after heat exchange in the hot platen is removed by keeping the boat fully open until then. Change it to water and flush it away.

Generally, the hot platen 2.3 is held at a steam set temperature t,'c, and then a plurality of inner layer substrates integrated via an insulating adhesive layer are hot-pressed into the hot platen 2.3.

3, and laminated adhesion is started by applying heat and pressure. Thereafter, the temperature of the heating platen is kept constant, during which time the viscosity of the insulating adhesive layer decreases once, and before gelation begins, the pressure is increased to completely fill the spaces between the plurality of inner layer substrates and bond them together. Insulating adhesive layer, then.

As the polymerization reaction progresses, the material hardens and shrinks, but the temperature is raised in order to make the polymerization reaction occur faster and more fully.

Generally, the steam used in this mechanism is 9Ktf/dG17
Since the temperature is approximately 5 cc, other heating medium is required for materials that require heating at a temperature higher than that, and in this embodiment, an electric heater is used to raise the temperature to the electric heater set temperature t2. During this time, it is heated from 172'C to 180°C using both steam and an electric heater. Thermocouple 106 is 1
When 800C is detected, the steam valve 10 and the drain,
12 Close outlet valve 15. However, the blow outlet valve 14 is fully opened for only 2 seconds once every 60 seconds in order to release the pressure in the pipe path inside the heating plate.

Next, after heating the electric heater to maintain it at the electric heater set temperature t2゜c for a certain period of time, the electric heater is turned off.
Before cooling, close the blow valve 14 for 10 seconds.

Fully open and blow. Next, the steam manifold valve 10 is opened based on the value set by the potentiometer 109 that sets the steam cooling temperature, and steam is allowed to flow for a certain period of time. Note that the blow throttle valve 31f1 is fully open during steam cooling, so the throttle valve 33 shown in FIG. 1 is suitable.

By proper adjustment, cooling rates of the order of 2°C per minute can be obtained. Also, during steam cooling, the blow outlet valve 14 closes once every 60 seconds.
The drain outlet valve 15 is fully opened for 2 seconds at the same time as the blow outlet valve 14 is opened, and the drain outlet valve 15 is closed for 2.5 seconds at 1-1 at the same time.
Open fully except during steam cooling.

Next, when the thermocouple 106 detects 172°C, 1
Steam and cooling water are used together for cooling until the temperature drops to 00°C. First, the cooling water population valve 12° and the cooling water outlet valve 11
is open for 60 seconds to cool, while the other valves are closed. The opening degree of the cooling water population valve 12 is determined by the cooling water indication controller 11 based on the command from the personal computer 101.
0, it is controlled -1 via the electropneumatic positioner 24. And next, steam population valve 10 and de.

The drain outlet valve 15 is opened for 10 seconds, and by reducing the cooling rate, a temperature lowering rate that cannot be obtained by cooling only with cooling water is obtained. During this time, other valves are closed. This operation is repeated until a temperature of 100°C is detected and 1 is reached.
After detecting C, cool it with only cooling water and connect 5゜thermocouple 1.
16 detects 60° C., the control ends, and the cooling water population valve 12 and the cooling water outlet valve 11 are fully opened to continue cooling until the end time of lamination adhesion. Lamination adhesion end time, -.

When the pressure of the hot press reaches 2.6, the pressure of the hot press is released, and the
A gap opens and the lamination adhesion is completed.

According to this example, by using steam and cooling water together during cooling under a precise temperature control system, the temperature increase rate and temperature decrease rate can be increased from 2°C to 8°C per minute from room temperature to about 250cc. Up to C.

It can be set arbitrarily and controlled with high precision between the two. In addition, with regard to variations in the surface and temperature of the heating plate during heating and cooling, the heating and cooling times were 30°C compared to the conventional method.
°Cvc can be significantly reduced to 50 °C (20) 0C during cooling. So it's wooden.

The multilayer printed wiring board, which is laminated and bonded at the same time, is stable and has less board deformation such as warpage and twisting, dimensional expansion and contraction, and residual stress inside the board compared to conventional boards.

You can get quality. i.

Steam cooling is also used as a cooling method in high temperature ranges.

Risk of water hammer etc. due to application.

Able to perform hard and safe work.

〔Effect of the invention〕

As described above, according to the present invention, the cooling medium is used as a cooling medium under a precise 1° temperature control system.

It is stable because steam and cooling water are used together.

It is said that high-quality multilayer printed wiring boards can be obtained.

effective.

[Brief explanation of drawings]

Fig. 1 is a piping diagram showing the heating and cooling mechanism, Fig. 2 is a block diagram showing the steam control mechanism, Fig. 3 is a block diagram showing the cooling water control mechanism, and Fig. 4 is a model of the set temperature pattern. Figure 4 (b+ is a time chart showing the control transition of the corresponding heating/cooling mechanism. 1... Hot press, 2.6... Hot plate, 10...
vapor. Large mouth valve, 11... Cooling water outlet valve, 12... Cooling water population valve, 16... Blow throttle valve, 14... Blow outlet. Valve, 15...Drain outlet valve, 25.24...Electro-pneumatic valve II + positioner, 101...Personal computer. 102...Steam indicating controller, 106.104...Po. Temperature converter, 106.113...Thermocouple, . 107.108.109...Potency meter, 11
0...Cooling water indicator controller, 111...Potency. 1 converter, 114...potentiometer, 16 ・

Claims (1)

[Claims] 1. In a method for manufacturing a multilayer printed wiring board by heating and pressurizing a plurality of inner layer substrates in a hot press, after the hot press is heated with steam, the temperature is further increased by another heating source. A method for manufacturing a multilayer printed wiring board, which comprises heating the board, then cooling it with steam, and then cooling it by using a combination of steam and cooling water. 2. In an apparatus for manufacturing a multilayer printed wiring board by heating and pressurizing a plurality of inner layer base materials in a hot press, a means for heating the hot press with steam, another heating means for further heating the hot press to an elevated temperature; A means for cooling a hot press with cooling water, heating with steam by the other heating means after heating with steam while detecting the temperature of a hot plate of the hot press, and then cooling with steam, and then using steam and cooling water together. A manufacturing apparatus for a multilayer printed wiring board, comprising means for controlling the heating platen so as to cool the heating platen.