JPH05317775A - Automatic application device for heated cementing material - Google Patents

Abstract

PURPOSE:To generate automatically a rough pattern of a heated cementing material by providing a nozzle mechanism for feeding a mixture of a heat cementing material and a non-plastic modified material to a cementing section and a control means for controlling the mixing ratio of the heat cementing material and the non-plastic modified material. CONSTITUTION:A first tank 20 and a second tank 40 for storing liquid solder and ceramic grains are disposed respectively for the purpose of mixing a non- plastic modified material, for example, ceramic grains, with a heat cementing material, for example, liquid solder in an automatic heat cementing material application device. A nozzle mechanism 80 for mixing liquid solder with ceramic grains and fed to a cementing interface between one component of electrical equipment, for example, a hybrid IC base and another component, for example, a sheet sink 1 is provided. Also a computer 10 as a control means for controlling changeably the mixing ratio of liquid solder and ceramic grains at the cementing interface is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is a hybrid I
The present invention relates to an automatic heat-bonding agent application device capable of automatically generating a coarse / dense pattern of the heat-bonding agent on a bonding surface between a C substrate and a heat sink.

[0002]

2. Description of the Related Art Conventionally, in a case where a heat sink is joined to a hybrid IC substrate, solder is applied to the joining surface with a uniform thickness to carry out the joining. Even when an IC chip, for example, a heating element such as a power transistor is mounted on this hybrid IC substrate, it is joined by solder. As this solder, for example, Au-
When using a solder made of Si alloy, heating at a high temperature of about 400 ° C. is necessary. For this reason, it is unavoidable that the characteristics of the semiconductor device deteriorate, particularly in an example in which a large number of IC chips are mounted, such as a thick film hybrid IC substrate. Further, solder is also used for joining the IC chip and the lead wire. The above solder is applied by an automatic solder applying device.

[0003]

However, when the solder is applied to each of the joint surfaces with a uniform thickness by the automatic solder applicator, the peripheral joint strength is apt to be affected by mechanical external force. It was inadequate compared to that. Furthermore, residual stress tends to occur inside the solidified solder. For these reasons, the hybrid IC substrate is likely to warp. Then, in the central portion where the external force is concentrated, inconveniences such as cracking and peeling of the IC chip and the like are likely to occur. In particular, there is a problem that cracks occur inside the solidified solder and cracks easily occur at each joint interface. on the other hand,
In the case of a hybrid IC substrate and a heat sink obtained by bonding different kinds of materials having different thermal expansion coefficients, when they are used in a high temperature atmosphere, their joint surfaces are apt to be misaligned and easily damaged, resulting in good thermal conductivity. There was also a problem that it was difficult to obtain.

[0004]

DISCLOSURE OF THE INVENTION The inventors of the present application have been able to apply the above-described problem by applying solder densely and densely on the bonding surface between the hybrid IC substrate and the IC chip, heat sink, etc., without applying the solder to a uniform thickness. We obtained the finding that

[0005]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an automatic heating bonding agent coating device capable of automatically generating a coarse / dense pattern of solder on a bonding surface between a hybrid IC substrate and a heat sink or the like.

[0006]

The automatic heating bonding agent applying apparatus of the present invention is an automatic heating bonding agent applying apparatus for applying a heating bonding agent mixed with a non-plastically deformed material to a bonding portion. A first tank for storing the heated bonding agent, a second tank for storing the non-plastic deformation product, the heating bonding agent sent from the first tank, and the non-plastic deformation product sent from the second tank. A nozzle mechanism for mixing and supplying the mixture to the joint portion, and a control means for controlling the mixing ratio of the heated joint agent and the non-plastically deformed material.

[0007]

In the automatic heating bonding agent application device according to the present invention, a heating bonding agent, for example, liquid solder, a non-plastic deformable material,
For example, in order to mix the ceramic particles, a liquid solder and a first tank and a second tank for storing the ceramic particles are provided, respectively. A nozzle mechanism is provided which mixes the liquid solder and the ceramic particles and supplies the liquid solder and ceramic particles to the interface between one component of the electronic device, for example, a hybrid IC substrate, and another component, for example, the sheet sink. .. Further, control means for controlling the mixing ratio of the liquid solder and the ceramic particles to be changeable at the interface of the joining is provided. For example, the liquid solder or the like applied to the joint surface between the hybrid IC substrate and the heat sink is formed so that the distribution immediately below the mounting position of the power transistor is dense (the ceramic powder is less or less than the liquid solder), The distribution other than directly under the power transistor is formed sparsely (there is more ceramic powder than liquid solder, or only ceramic grains). Therefore, in the joint portion between the components of the electronic device, the dense and dense pattern of the heated bonding agent is automatically generated according to the data regarding the heat generation of the electronic device which is input in advance.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an automatic heating bonding agent coating device according to the present invention will be described below with reference to FIGS.

As shown in FIG. 1, this automatic heating bonding agent application apparatus has a solder tank 20 for storing solder, for example, Pb-63% Sn (eutectic solder), and this solder tank 20.
Solder heater 30 that heats the solder inside, ceramics tank 40 that stores ceramics particles, for example, alumina particles having a particle size of 50 μm, and solenoid valves 21, 41 attached to soldering tank 20 and ceramics tank 40 , A mixer 60 for mixing the liquid solder in the solder bath 20 and the ceramic powder in the ceramic 40 bath, a mixing heater 70 for heating this mixture, and a heat sink for this heating bonding agent. Nozzle 80 for coating on one surface (bonding surface with hybrid IC),
X to move the nozzle 80 to a predetermined position in the XY direction
-Y drive mechanism 90, conveyor 100 that conveys heat sink 1 to the right, and position sensors 110 and 111 that detect the position of heat sink 1 above this conveyor 100.
And a computer 10 for controlling the mixing ratio of liquid solder and ceramic particles on the surface of the heat sink 1.
And are composed of. In the solder bath 20, if solder particles of 50 μm or more are used,
In the mixer 60, it is possible to mix and melt the ceramic particles at the same time, which facilitates mixing. Further, hard metal such as hard sphere or tungsten sphere may be used instead of the ceramic particles as the non-plastically deformable material. At this time,
The wettability with solder is improved.

The computer 10 includes a processing device main body,
It is composed of a keyboard, a monitor, an FBS (flatbed scanner), a magnetic disk device, a mouse and the like. The input unit is composed of a monitor, an FBS, a magnetic disk device, a keyboard, a mouse and the like. The processing device main body includes a well-known CPU, ROM, RAM,
It is composed of an I / O unit and the like.

The I / O unit of the processor of the computer 10 includes a temperature sensor for the solder bath 20 and a solder heater 3.
0, drive circuit 50, mixing heater 70, XY drive mechanism 9
0 and position sensors 110 and 111 are connected respectively. Further, solenoid valves 21 and 41 are connected to the drive circuit 50, respectively.

In the automatic heating bonding agent coating device having the above-mentioned structure, the power transistor of the computer, the FBS, the magnetic disk device, the keyboard or the mouse is used as data relating to the heat generation of the electronic device, for example, the semiconductor device. The quantity / type / maximum heat generation / mounting position, hybrid IC board pattern / material / thickness, heat sink material / shape, solder type / viscosity, ceramic grain type / grain size, etc. are entered. Then, based on the data of these heating elements and the like, the processing apparatus main body determines the mixing ratio of the liquid solder and the ceramic particles forming the heating bonding agent. Further, the application position of this heated bonding agent is determined. Then, the determined heating bonding agent is applied to the determined position on the bonding surface between the hybrid IC substrate and the heat sink 1, for example. As a result, the heating bonding agent applied to the bonding surface between the hybrid IC substrate and the heat sink 1 is formed so that the distribution just below the mounting position of the heating element is dense (the ceramic powder is small or absent with respect to the solder). The distribution other than directly under the heating element is formed sparsely (there is more ceramic powder than solder, or only ceramic particles).

The program of this automatic heating bonding agent coating device will be described below with reference to FIGS. 1 and 2. When the computer 10 is turned on, this program is executed by the CPU.
Is what is executed in. Before the power is turned on, solder is put in the solder bath 20 and ceramic particles are put in the ceramic bath 40. In addition, solenoid valve 2
1, 41 and the nozzle 80 are closed. First, a memory such as a RAM is initialized by performing a clearing process or the like (S1). Next, the FBS of the computer 10, the magnetic disk device,
From a monitor, keyboard or mouse, use the data on the number of power transistors
Type, maximum heat generation, mounting position on hybrid IC board, material / thickness / pattern of hybrid IC board, heat sink 1 material / shape, solder type / viscosity, ceramic grain type / grain size, etc. Done (S
2). For example, by inserting a drawing of an electronic circuit or the like into the FBS, data regarding heat generation of the electronic device is input.

Next, based on the input data, the CPU of the computer 10 determines the mixing ratio of the liquid solder and the ceramic particles constituting the heating bonding agent and the coating position of this heating bonding agent on the surface of the heat sink 1. Determine (S
3). According to this mixing ratio, the CPU determines whether the solder heater 3
0 to send a heating signal to the drive circuit 50 and the solenoid valve 21,
Each valve opening signal of 41 is transmitted, a heating signal is transmitted to the mixing heater 70, and a mixing rotation signal is transmitted to the mixer 60 (S4). As a result, the solder is heated to a predetermined temperature. The drive circuit 50 sends a signal to open the solenoid valves 21 and 41, respectively. The solenoid valves 21 and 41 are opened at a predetermined opening. The heated liquid solder and ceramic particles are mixed in the mixer 60. In the mixer 60, the liquid solder and the ceramic particles are heated to a predetermined temperature and uniformly mixed and rotated.

Next, it is judged whether the temperature of the heated liquid solder in the solder bath 20 is proper (S5). If it is proper, the process proceeds to step S7. When it is not proper, that is, when the amount of solder increases or decreases and the temperature of the solder is higher or lower than the predetermined temperature, the level of the heating signal of the solder heater 30 is increased or decreased (S6). Similarly, it is determined whether the temperatures of the liquid solder and the ceramic powder heating bonding agent in the mixer 60 are appropriate (S7). If it is proper, the process proceeds to step S9. If it is not appropriate, the level of the heating signal of the mixing heater 70 is increased or decreased (S8). As a result, the heated bonding agent is kept at a predetermined temperature even if the liquid solder and the ceramic powder increase or decrease.

Next, it is determined whether or not the position sensor 110 has found the heat sink 1 conveyed rightward by the conveyor 100 (S9). If not found, the process returns to step S5. If found, the initial position signal of the nozzle 80 determined from the application position of the heated bonding agent determined in step S3 is transmitted to the XY drive mechanism 90 (S1).
0). As a result, the nozzle 80 moves to a predetermined position above the heat sink 1 (on the side where the hybrid substrate is joined),
The tip of the nozzle 80 approaches the vicinity of the surface of the heat sink 1. Then, the nozzle 80 is opened, and the heating bonding agent is applied from this nozzle 80 to a predetermined point on the surface of the heat sink 1. From this predetermined point, the conveyor 100 is moved while being coated with the hot bonding agent.

Next, it is judged whether or not the opening degrees of the solenoid valves 21, 41 are adjusted (S11). When not adjusting, it progresses to step S13. Solenoid valve 2 when adjusting
The opening change signals of 1, 41 are transmitted to the drive circuit 50 (S12). As a result, the drive circuit 50 adjusts at least the opening degree of the solenoid valve 21 or the solenoid valve 41. Then, the mixing ratio of the liquid solder of the heating bonding agent applied from the nozzle 80 and the ceramic powder changes.

Next, it is determined whether or not to move the XY drive mechanism (S13). If it is not moved, the process proceeds to step S15. When moving, XY drive mechanism 9
A movement signal is transmitted to 0 (S14). As a result, X
The -Y drive mechanism 90 moves the nozzle 80 above the surface of the heat sink 1 based on the movement signal. And
The nozzle 80 moves while applying a heating bonding agent on the surface of the heat sink 1.

Then, it is determined whether or not to end based on the signal from the position sensor 111 (S15). When finished, the process proceeds to step S16. If not completed, the process returns to step S11. As a result, a coarse and dense pattern is automatically formed on the heat sink 1 based on the data relating to the heat generation of the semiconductor device. For example, the heating bonding agent applied to the bonding surface between the hybrid IC substrate and the heat sink 1 has a dense distribution (there is no ceramic powder for liquid solder) immediately below the mounting position of the power transistor. The distribution other than immediately below is formed sparsely (more ceramic powder than liquid solder).

Next, the nozzle close signal is transmitted to the XY drive mechanism 90 (S16). As a result, the nozzle 80 is closed by the XY drive mechanism 90. Then, the nozzle 80 floats above the heat sink 1. Finally, the process returns to step S1.

By giving such a sparse / dense distribution to the joint surface between the hybrid IC substrate and the heat sink 1, the residual stress after the joint is reduced, the laminated body composed of the hybrid IC substrate and the heat sink 1 is warped, and the joints thereof are joined. The phenomenon of peeling at the interface can be suppressed. In particular, in the peripheral portion of the laminated body, plastic deformation due to an external force is facilitated, so that stress relaxation and residual stress reduction can be performed more effectively. Further, if such a laminate is used at a high temperature, the portion where the solder is densely applied is at the joint interface and the contact area is large, so the thermal conductivity is good and product defects can be reduced. it can. Furthermore, if the density distribution of the solder is continuously changed from the central portion toward the peripheral portion, the effect of the present invention is further enhanced. In addition, similarly, the automatic heating bonding agent coating device can be applied to the bonding portion between the hybrid IC substrate and the power transistor or the like.

As described above, in the joining portion of the components of the electronic device, the automatic heating bonding agent applying device automatically generates the coarse and dense pattern of the heating bonding agent in accordance with the data about the heat generation of the electronic device which is input in advance. It is possible. By automating the rough and dense pattern, it is possible to inexpensively manufacture an electronic device that does not cause warping or bending of the circuit board of the electronic device or deformation such as peeling or cracking of the heating bonding agent.

[0023]

The automatic heating bonding agent coating device of the present invention is capable of automatically generating a coarse and dense pattern of the heating bonding agent when the heating bonding agent is applied at the joint between the components of the electronic equipment. is there. By automating the rough and dense pattern, it is possible to inexpensively manufacture an electronic device that does not cause warping or bending of the circuit board of the electronic device or deformation such as peeling or cracking of the heating bonding agent.

[Brief description of drawings]

FIG. 1 is a block diagram showing an automatic heating bonding agent coating device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing an operation procedure of the automatic heating bonding agent coating device according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 heat sink 10 computer (control means) 20 solder bath (first bath) 40 ceramics bath (second bath) 60 mixer (nozzle mechanism) 70 XY drive mechanism (nozzle mechanism) 80 nozzle (nozzle mechanism)

Claims (1)

[Claims] 1. An automatic heating bonding agent application device for applying a heating bonding agent mixed with a non-plastic deformation material to a bonding portion, the first tank storing the heating bonding agent, and the non-plastic deformation material. A second tank for storing, a heating mechanism sent from the first tank, and a nozzle mechanism for mixing the non-plastic deformation product sent from the second tank and supplying the mixture to the joint part, and the heating joint. An automatic heating bonding agent coating device comprising: a control unit for controlling a mixing ratio of the adhesive and the non-plastic deformation product.