JP2787057B2 - Die bonding equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an upper mechanism for holding and fixing a chip element such as a bare chip semiconductor element and other surface mounting circuit elements by die bonding to a case or another wiring board. The present invention also relates to a die bonding apparatus provided with a heating stage having a mechanism for holding and fixing a case or another wiring board for die-bonding a chip element, which is disposed therebelow.

[0002]

2. Description of the Related Art As shown in FIG. 4, a generally used die bonding apparatus is provided with an upper mechanism 12 to which a tool called a die collet 1 for adsorbing and fixing a chip element is attached and a lower part thereof. Heating stage 13
It is composed of

The upper mechanism 12 has a function of sliding the die collet 1 and preheating the chip element via the die collet 1, and a heating stage 13 places the case 4 or another wiring board on the hot plate 14. It is structured to be supported and fixed.

FIG. 5 is a longitudinal sectional view showing a state in which the chip element 3 is die-bonded to the case 4 by the die bonding apparatus of FIG.

[0005] The die bonding procedure includes gold tin solder,
When using a brazing material such as tin-lead solder, first, the inner bottom surface of the case 4 disposed on the hot plate 14 of the heating stage 13 is melt-coated with the brazing material 11 and then the chip element 3 is adsorbed. Die collet 1 is dropped and case 4
After being brought into contact with the molten brazing material 11 on the inner bottom surface of the case, the die collet 1 is slid back and forth by the upper mechanism 12 to bring the chip element 3 into close contact with the inner bottom surface of the case 4.
The die collet 1 is removed from the chip element 3, and the case 4 is lowered from above the hot plate 14 of the heating stage 13 to remove the brazing material 1.
1 is slowly cooled and cured.

In the case of die bonding using a thermosetting adhesive, the hot plate 14 is heated by bringing the chip element 3 into close contact with the die collet 1 on the bottom surface of the case 4 to which the adhesive has been applied in advance. To cure the adhesive.

As another die bonding apparatus, there is a die bonding apparatus (Japanese Patent Application No. 2-9226) which has been filed by the present inventors and which is also used for alignment as shown in FIGS.
No. 7). This device is for die-bonding a chip element mounted on a small flexible wiring board having a shape used in a high-frequency region to a case or another wiring board. In the device using a die collet shown in FIG. This device has solved the disadvantage that the chip element cannot be fixed by suction using the die collet due to the obstruction of the flexible wiring board.

The procedure for die bonding using the brazing material 11 such as gold-tin solder or tin-lead solder by the present apparatus is as follows. First, the heating plate 1 of the heating stage
The inner bottom surface of the case 4 supported and fixed to the case 4 is melt-coated with the brazing material 11, and then the flexible wiring board 15 on which the chip element 3 is mounted is accommodated in the case 4. The flexible wiring board 15 is supported and fixed by pins 17 extended from micromanipulators 16 arranged on the left and right, and flexible wiring is performed by an X-axis and Y-axis movable mechanism 18 and a rotating mechanism 19 of a heating stage to which the hot plate 14 is attached. External lead 20 of plate 15 and electrode terminal 21 of case 4
Is aligned with Further, the chip element 3 mounted via the flexible wiring board 15 is pressed by the pins 17 so that the chip element 3 and the inner bottom surface of the case 4 are brought into close contact with each other. Thereafter, the case 4 is lowered from above the hot plate 14 and the brazing material 11 is gradually cooled and hardened.

[0009]

When a high-frequency chip element is die-bonded in a case and a wire is connected between an electrode of the chip element and an electrode terminal of the case, the wire length must be reduced in order to reduce the inductance component of the wire. It is necessary to keep it as short as possible. For this purpose, die bonding must be performed by bringing the inner wall of the case having the electrode terminals close to the chip element. However, in the conventional die bonding apparatus as shown in FIG. 4, since the sliding stroke of the die collet 1 is as large as about 0.3 to 1 mm, a large sliding space is required, and the distance between the chip element and the inner wall of the case is reduced. There is a disadvantage that it cannot be made smaller.

Further, in order to die-bond a chip element mounted on a small flexible wiring board having a shape used in a high-frequency region to a case or another wiring board, FIGS. 7 is a die bonding device that is also used for alignment (Japanese Patent Application No. 2-922).
No. 67), the operation for die-bonding the chip element 3 mounted on the flexible wiring board 15 to the inner bottom surface of the case 4 is only a static load by the pins 17 extended from the micromanipulator 16, so that the chip There is a case where a gap is formed in the brazing material 11 at the interface between the element 3 and the case 4, and there is a disadvantage that the bonding is not securely performed and the reliability of die bonding is impaired. Even when an adhesive is used, voids are similarly generated, and there is a disadvantage that highly reliable die bonding cannot be performed.

The present invention has been made in view of the above-mentioned problems, and has as its object to reduce the sliding stroke between the chip element and the inner bottom surface of the case. It is an object of the present invention to provide a die bonding apparatus suitable for die-bonding a chip element mounted on a small-sized flexible wiring board used in a region to a case or another wiring board with high accuracy and reliability.

[0012]

In a die bonding apparatus according to the present invention, a heating stage includes an ultrasonic oscillation source, a diaphragm for supporting and fixing a case or a wiring board on an upper surface, and an ultrasonic oscillation source for horizontally moving the diaphragm. And a vibration horn that horizontally vibrates the case or the wiring board by the ultrasonic vibration generated by the ultrasonic oscillation source, and heat that is disposed below the vibration plate and heats the case or the wiring board through the vibration plate Plate, a Z-axis movable mechanism for vertically moving the hot plate, a rotary mechanism for rotating and linearly moving the ultrasonic oscillation source and the Z-axis movable mechanism in a horizontal plane, and an X-axis and Y-axis movable mechanism, respectively. And

[0013]

According to the present invention, a vibration plate, a vibration plate, and a heating stage for supporting and fixing and heating a case or another wiring board are not provided in an upper mechanism for supporting and fixing the chip device. Is provided with an ultrasonic vibration mechanism for vibrating the liquid crystal in the horizontal direction.

With such a structure, the heating stage can be moved with respect to the bottom surface of the chip element sucked and fixed by the die collet of the upper mechanism or the chip element mounted on the flexible wiring board supported and fixed by the micromanipulator. Since the chip element mounting surface of the case or other wiring board supported and fixed to the diaphragm vibrates ultrasonically in the horizontal direction, the molten brazing material or adhesive is evenly dispersed on the bottom of the chip element, and the brazing material or adhesive is Highly reliable die bonding with no bubbles or voids inside is possible.

In this structure, ultrasonic waves are used as a method for bringing the chip element into close contact, and the sliding stroke can be reduced to about several tens of μm, so that the chip element can be brought closer to the inner wall of the case. Even when die-bonding chip elements mounted on a flexible wiring board, die bonding can be performed with high precision without adverse effects such as misalignment between the external leads of the aligned flexible wiring board and the electrode terminals of the case. can do.

[0016]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a front view of a die bonding apparatus according to a first embodiment of the present invention, and FIG. 2 is an enlarged sectional view thereof. The die bonding apparatus of the present embodiment is an example of a case in which a chip element is suction-fixed by a die collet to perform die bonding.

The upper mechanism 2 to which the die collet 1 is attached has a function of bringing the chip element into contact with the inner bottom surface of the case 4 and applying pressure from above. The heating stage arranged below the ultrasonic oscillation source 8, the small-sized vibrating plate 5 for supporting and fixing the case 4 or the wiring board on the upper surface, and connecting the vibrating plate 5 to the ultrasonic generating source 8 horizontally. And the ultrasonic oscillation source 8
A vibrating horn 7 for vibrating the case 4 or the wiring board in the horizontal direction by the ultrasonic vibration generated in the above, and a heating plate 6 disposed below the vibrating plate 5 and heating the case 4 or the wiring board via the vibrating plate 5. The Z-axis movable mechanism 6 'for moving the hot plate 6 in the vertical direction (Z-axis direction), the ultrasonic oscillation source 8 and the Z-axis movable mechanism 6' are rotated in a horizontal plane (XY plane).
Rotating mechanism 9 for linear movement and X-axis and Y-axis movable mechanism 10
It is composed of Since the vibration plate 5 has a structure in which the volume is reduced by dividing the heating plate 6, the case 4 can be efficiently vibrated with relatively small ultrasonic power.

Next, the operation of the present embodiment will be described for the case where a brazing material 11 such as gold-tin solder or tin-lead solder is used.

First, the case 4 is placed on the vibration plate 5, and the hot plate 6 is moved in the Z-axis direction by the Z-axis movable mechanism 6 ′ to come into contact with the vibration plate 5, and the vibration plate 5 is heated by the hot plate 6. Above, the inner bottom surface of the case 4 is melt-coated with the brazing material 11. Next, the rotation mechanism 9 and the X-axis Y-axis movable mechanism 10
Thus, the chip element 3 adsorbed to the die collet 1 and the case 4 are aligned. Subsequently, the die collet 1 is lowered to bring the chip element 3 into contact with the molten brazing material 11 on the inner bottom surface of the case 4, and at the same time, the ultrasonic oscillation source 8 is driven to vibrate the diaphragm 5, whereby the chip element 3 and the case are vibrated. 4. Make close contact with the inner bottom surface of 4. Thereafter, the die collet 1 is removed from the chip element 3, the case 4 is lowered from above the diaphragm 5, and the brazing material 11 is gradually cooled and hardened.

As described above, the die collet 1 of the upper mechanism 2
The inner bottom surface of the case 4 supported and fixed by the diaphragm 5 is horizontally ultrasonically vibrated with respect to the bottom surface of the chip element 3 sucked and fixed by the above, so that the molten brazing material 11 is uniformly dispersed on the bottom surface of the chip element 3. In addition, highly reliable die bonding can be performed without leaving bubbles and voids in the brazing material 11.

As a result, the sliding stroke can be made much smaller than that of the conventional die bonding apparatus. Therefore, the die element 3 and the inner wall of the case can be brought close to each other without causing the die collet 1 to contact the inner wall of the case 4 and with high accuracy. Die bonding can be performed.

FIG. 3 is a longitudinal sectional view of a die bonding apparatus according to a second embodiment of the present invention. The present embodiment is an example of a case in which a chip element mounted on a flexible wiring board is die-bonded.

The upper mechanism for supporting and fixing the flexible wiring board on which the chip elements are mounted has the same structure as that of FIG. 6, and the stage disposed below has the same structure as that of the first embodiment.

The bonding procedure when using a brazing material such as gold tin solder or tin lead solder is as follows. First, the brazing material 11 is melt-coated on the inner bottom surface of the case 4 supported and fixed to the diaphragm 5, and then the flexible wiring board 15 on which the chip element 3 is mounted is accommodated in the case 4. Subsequently, the flexible wiring board 15 is supported and fixed by a pin 17 extended from the micromanipulator 16, and is moved by an X-axis / Y-axis movable mechanism 10 and a rotation mechanism 9.
The external leads 20 of the flexible wiring board 15 and the electrode terminals 21 of the case 4 are aligned, and
Weights the chip element 3 mounted on the flexible wiring board 15, and drives the ultrasonic oscillation source 8 to vibrate the vibration plate 5, thereby causing the chip element 3 and the case 4 to vibrate.
Make tight contact with the inner bottom. Thereafter, the die collet 1 is removed from the chip element 3, the case 4 is lowered from above the diaphragm 5, and the brazing material 11 is gradually cooled and hardened.

In the conventional die bonding apparatus for both positioning and alignment shown in FIG. 6, the close contact between the chip element 3 and the inner bottom surface of the case 4 is performed only by the weight of the pins 17, but in the die bonding apparatus of this embodiment, Since the ultrasonic vibration is applied to the case 4 in a direction parallel to the inner bottom surface thereof, the molten brazing material 11 is uniformly dispersed on the bottom surface of the chip element 3 as described in the first embodiment. -Highly reliable and highly accurate die bonding can be performed without leaving voids.

When the adhesive is used, the first embodiment,
In both of the second embodiments, after the adhesive is applied to the inner bottom surface of the case 4 in advance, the chip element 3 and the electrode terminals 21 of the case 4 are aligned, and they are brought into close contact with each other while applying ultrasonic vibration. The plate 6 may be raised and brought into contact with the diaphragm 5, and the adhesive may be cured by heating.

[0028]

As described above, the present invention is applied to a case or another heating board for supporting and fixing a case or another wiring board disposed below an upper mechanism for supporting and fixing a chip element, and to a case or another heating stage. Providing a diaphragm for supporting and fixing the wiring board and an ultrasonic vibration mechanism (ultrasonic oscillation source and ultrasonic horn) for horizontally ultrasonically vibrating the diaphragm has the following effects. (1) A case or other wiring supported and fixed to a heating stage with respect to the bottom surface of a chip element that is sucked and fixed by a die collet of an upper mechanism or a chip element that is mounted on a flexible wiring board that is supported and fixed by a micromanipulator. Since the chip element mounting surface of the plate vibrates in parallel with ultrasonic waves, the molten brazing material or adhesive is evenly distributed on the bottom of the chip element, and highly reliable die bonding without bubbles or voids in the brazing material or adhesive is achieved. It becomes possible. (2) With this, the chip element sliding stroke for bringing the chip element into close contact can be extremely reduced as compared with the conventional die bonding apparatus using a die collet. Die bonding can be performed close to the inner wall of the case, so that the wire length connecting the chip elements can be shortened. That is, the inductance component due to the wire can be reduced, which is extremely effective in improving the high frequency characteristics. (3) Even when the chip element mounted on the flexible wiring board is die-bonded, the sliding stroke of the chip element can be made extremely small, so that the aligned external leads of the flexible wiring board and the electrode terminals of the case are positioned. It is possible to perform highly accurate and highly reliable die bonding without causing a problem such as displacement.

[Brief description of the drawings]

FIG. 1 is a front view of a die bonding apparatus according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view illustrating details of the device of FIG. 1 in the case where a chip element 3 is die-bonded to a case 4.

FIG. 3 is a longitudinal sectional view illustrating details of a case where a die bonding is performed to a case 4 in a die bonding apparatus according to a second embodiment of the present invention.

FIG. 4 is a side view showing a conventional example of a die bonding apparatus.

FIG. 5 is a longitudinal sectional view for explaining details of the case where the chip element 3 is die-bonded to the case 4 by the conventional die bonding apparatus of FIG.

FIG. 6 is a perspective view showing an example of the structure of a flexible wiring board positioning apparatus and a die bonding apparatus which the present inventors filed earlier.

FIG. 7 is a cross-sectional view illustrating a die bonding method using a positioning apparatus and a die bonding apparatus for a flexible wiring board, which was previously filed by the present inventors.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Die collet 2 Upper mechanism 3 Chip element 4 Case 5 Vibration plate 6 Hot plate 6 'Z-axis movable mechanism 7 Ultrasonic horn 8 Ultrasonic oscillation source 9 Rotation mechanism 10 X-axis Y-axis movable mechanism 11 Brazing material 12 Upper mechanism 13 Heating Stage 14 Heat plate 15 Flexible wiring board 16 Micromanipulator 17 Pin 18 X-axis Y-axis movable mechanism 19 Rotation mechanism 20 External lead of flexible wiring board 15 21 Electrode terminal of case 4

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-143435 (JP, A) JP-A-3-8347 (JP, A) JP-A-64-47034 (JP, A) JP-A-62-1987 26830 (JP, A) JP-A-62-78841 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01L 21/52, 21/58

Claims (1)

(57) [Claims] An upper mechanism for holding and fixing a chip element for die bonding a chip element such as a bare chip semiconductor element or another surface mounting circuit element to a case or another wiring board, and disposed below the upper mechanism. And a heating stage having a mechanism for holding and fixing a case or another wiring board for die bonding the chip element, wherein the heating stage comprises an ultrasonic oscillation source, the case or the wiring. A vibration plate for supporting and fixing the plate on the upper surface, and a vibration for horizontally connecting the vibration plate to the ultrasonic oscillation source, and vibrating the case or the wiring board in a horizontal direction by ultrasonic vibration generated by the ultrasonic oscillation source. A horn, a heating plate disposed below the diaphragm, and heating the case or the wiring board via the diaphragm, A Z-axis movable mechanism for moving the
A die bonding apparatus comprising: a rotation mechanism for rotating and linearly moving the ultrasonic oscillation source and the Z-axis movable mechanism in a horizontal plane, respectively, and an X-axis and Y-axis movable mechanism.