JPH04263436A - Diebonding device - Google Patents

Abstract

PURPOSE:To precisely diebond a chip element mounted on a small-sized flexible wiring board used in a high-frequency region onto a case or the other wiring board while shortening the sliding stroke on the chip element and the bottom surface in the case within the title diebonding device. CONSTITUTION:The heating stage arranged beneath an upper mechanism 2 is composed of a vibration board 5, a hot plate 6, a Z-axial movable mechanism 6', an ultrasonic horn 7, an ultrasonic oscillator 8, a rotating mechanism 9 and X and Y axial movable mechanism 10. The vibration board 5 whereon a case 4 is support-fixed is horizontally connected to the ultrasonic oscillator 8 by the ultrasonic horn 7 so as to be vibrated in the horizontal direction by the ultrasonic horn 7 due to the ultrasonic vibration generated a by the ultrasonic oscillator 8. On the other hand, the hot plate 6 shifted by the Z-axial movable mechanism 6' comes into contact with the vibration board 5 so as to heat the vibration board 5.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention provides an upper mechanism for holding and fixing chip elements such as bare chip semiconductor elements and other surface-mounted circuit elements for die bonding to a case or other wiring board. The present invention relates to a die bonding apparatus including a heating stage disposed below the heating stage and having a mechanism for holding and fixing a case for die bonding chip elements or another wiring board.

0002

2. Description of the Related Art A commonly used die bonding apparatus, as shown in FIG. 4, includes an upper mechanism 12 to which a tool called a die collet 1 is attached, which fixes a chip element by suction, and an upper mechanism 12 disposed below the upper mechanism 12. It is composed of a heating stage 13.

The upper mechanism 12 has the function of sliding the die collet 1 and preheating the chip element via the die collet 1, and the heating stage 13 has the function of sliding the die collet 1 and preheating the chip element through the die collet 1. Also, the heating stage 13 has the function of sliding the die collet 1 and preheating the chip element through the die collet 1. It has a structure that supports and fixes it.

FIG. 5 is a longitudinal cross-sectional view showing how the chip element 3 is die-bonded to the case 4 using the die-bonding apparatus shown in FIG.

[0005] The die bonding procedure includes gold-tin solder,
When using a brazing material such as tin-lead solder, the brazing material 11 is first melted and coated on the inner bottom surface of the case 4 placed on the hot plate 14 of the heating stage 13, and then the chip element 3 is adsorbed. Lower the die collet 1 and press case 4.
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, and then,
Remove the die collet 1 from the chip element 3, lower the case 4 from above the heating plate 14 of the heating stage 13, and remove the brazing material 1.
1 is cured by slow cooling.

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

As another die bonding device, a die bonding device for positioning as shown in FIGS. 6 and 7 previously filed by the present inventors (Japanese Patent Application No. 2-9226
No. 7). This device is for die bonding a chip element mounted on a small flexible wiring board used in a high frequency region to a case or another wiring board. This device eliminates the drawback of not being able to suction and fix chip elements using a die collet due to the obstruction of the flexible wiring board.

The procedure for die bonding using a brazing material 11 such as gold-tin solder or tin-lead solder using this apparatus is as follows. First, heat plate 1 of the heating stage
A brazing material 11 is fused and coated on the inner bottom surface of the case 4 supported and fixed to the case 4, and then the flexible wiring board 15 on which the chip element 3 is mounted is housed 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 the flexible wiring is fixed by the X-axis and Y-axis movable mechanism 18 and rotation mechanism 19 of the heating stage to which the heating plate 14 is attached. External lead 20 of plate 15 and electrode terminal 21 of case 4
Perform alignment with Further, the chip element 3 mounted via the flexible wiring board 15 is pressurized by the pin 17, and the chip element 3 and the inner bottom surface of the case 4 are brought into close contact. Thereafter, the case 4 is lowered from above the hot plate 14, and the brazing filler metal 11 is slowly cooled and hardened.

[0009]

[Problems to be Solved by the Invention] When die-bonding a high-frequency chip element into a case and connecting wires between the electrodes of the chip element and the electrode terminals of the case, it is necessary to increase the length of the wire in order to reduce the inductance component of the wire. It is necessary to keep it as short as possible. For this purpose, the inner wall of the case where the electrode terminals are located must be brought close to the chip element for die bonding. However, in the conventional die bonding apparatus as shown in FIG. 4, the sliding stroke of the die collet 1 is large, approximately 0.3 to 1 mm, so a wide sliding space is required, and the gap between the chip element and the inner wall of the case is large. The disadvantage is that the distance cannot be reduced.

In addition, in order to die bond a chip element mounted on a small-sized flexible wiring board used in a high frequency region to a case or another wiring board, the present inventors have applied the method of FIG. 6 and FIG. A die bonding device for positioning as shown in 7 (Japanese Patent Application No. 2-922)
No. 67), the only 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 static loading using the pin 17 extended from the micromanipulator 16. A void may be formed in the brazing material 11 at the interface between the element 3 and the case 4, and there is a drawback that the reliability of die bonding is impaired because the bonding is not ensured. Even when an adhesive is used, voids are similarly generated, and highly reliable die bonding cannot be performed.

The present invention has been made in view of the above problems, and its purpose is to reduce the sliding stroke between the chip element and the inner bottom surface of the case, thereby making it possible to perform die bonding in a narrow area. It is an object of the present invention to provide a die bonding device suitable for highly precisely and reliably die bonding a chip element mounted on a small-sized flexible wiring board used in a region to a case or other wiring board.

0012

[Means for Solving the Problems] The die bonding apparatus of the present invention includes a heating stage that includes an ultrasonic oscillation source, a diaphragm that supports and fixes a case or a wiring board on its upper surface, and a diaphragm that horizontally holds the diaphragm as an ultrasonic oscillation source. A vibration horn that is connected to the ultrasonic oscillation source and vibrates the case or wiring board horizontally using the ultrasonic vibrations generated by the ultrasonic oscillation source, and a vibration horn that is placed below the diaphragm and heats the case or wiring board through the diaphragm. A Z-axis movable mechanism that moves the plate and the hot plate in the vertical direction, and a rotation mechanism and an X-axis and Y-axis movable mechanism that rotate and linearly move the ultrasonic oscillation source and the Z-axis movable mechanism in a horizontal plane, respectively. shall be.

[0013]

[Operation] In the present invention, the upper mechanism for supporting and fixing the chip element is not provided with a mechanism for sliding the chip element, and the heating stage that supports and fixes the case or other wiring board and heats it is equipped with a diaphragm and a diaphragm. The structure is equipped with an ultrasonic vibration mechanism that vibrates horizontally.

[0014] With this structure, the heat of the heating stage can be applied to the bottom surface of a chip element that is suctioned and fixed by the die collet of the upper mechanism or that is mounted on a flexible wiring board that is supported and fixed by a micromanipulator. Since the chip element mounting surface of the case or other wiring board supported and fixed on the diaphragm is vibrated horizontally by ultrasonic waves, the molten brazing filler metal or adhesive is uniformly distributed on the bottom surface of the chip element, causing the brazing filler metal or adhesive to Air bubbles inside
Highly reliable die bonding without voids is possible.

[0015] In this structure, ultrasonic waves are used as a method for bringing the chip element into close contact with each other, and since the sliding stroke can be reduced to about several tens of micrometers, the chip element and the inner wall of the case can be brought close to each other. Even when die bonding chip elements mounted on a flexible wiring board, die bonding can be performed with high precision without causing negative effects such as misalignment of the aligned external leads of the flexible wiring board and the electrode terminals of the case. can do.

[0016]

Embodiments 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 this embodiment is an example in which die bonding is performed by sucking and fixing a chip element using a die collet.

The upper mechanism 2 to which the die collet 1 is attached has the 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 at the bottom includes an ultrasonic oscillation source 8, a small-volume diaphragm 5 that supports and fixes the case 4 or the wiring board on the upper surface, and the diaphragm 5 is horizontally connected to the ultrasonic oscillation source 8. and ultrasonic oscillation source 8
a vibration horn 7 that vibrates the case 4 or the wiring board in the horizontal direction using ultrasonic vibrations generated by the vibration horn 7; , a Z-axis movable mechanism 6' that moves the hot plate 6 in the vertical direction (Z-axis direction), and a rotation of the ultrasonic oscillation source 8 and Z-axis movable mechanism 6' in a horizontal plane (XY plane),
Rotation mechanism 9 for linear movement and X-axis and Y-axis movable mechanism 10
It is made up of. In this way, since the diaphragm 5 has a structure in which the heat plate 6 is divided to reduce the volume, the case 4 can be efficiently vibrated with a relatively small ultrasonic power.

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

First, the case 4 was placed on the diaphragm 5, and the heating plate 6 was moved in the Z-axis direction by the Z-axis moving mechanism 6' to contact the diaphragm 5, and the diaphragm 5 was heated by the heating 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 and Y-axis movable mechanism 10
The chip element 3 adsorbed on the die collet 1 and the case 4 are aligned with each other. Subsequently, the die collet 1 is lowered to bring the chip element 3 into contact with the melted brazing filler metal 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, thereby separating the chip element 3 and the case. Bring it into close contact with the inner bottom surface of No. 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 slowly cooled and hardened.

In this way, the die collet 1 of the upper mechanism 2
By horizontally ultrasonically vibrating the inner bottom surface of the case 4 supported and fixed on the diaphragm 5 against the bottom surface of the chip element 3 which is suctioned and fixed by the , highly reliable die bonding can be performed without leaving any bubbles or voids in the brazing filler metal 11.

[0022] This allows the sliding stroke to be extremely smaller than that of conventional die bonding equipment, so that the die collet 1 does not come into contact with the inner wall of the case 4, and the chip element 3 and the inner wall of the case 4 are brought closer to each other with high precision. Can be die bonded.

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

The upper mechanism for supporting and fixing the flexible wiring board on which chip elements are mounted has the same structure as that shown in FIG. 6, and the stage disposed below has the same structure as in 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 inner bottom surface of the case 4 supported and fixed to the diaphragm 5 is melt-coated with a brazing material 11, and then the flexible wiring board 15 on which the chip element 3 is mounted is housed in the case 4. Subsequently, the flexible wiring board 15 is supported and fixed by pins 17 extended from the micromanipulator 16, and the external leads 20 of the flexible wiring board 15 and the electrode terminals 21 of the case 4 are connected by the X-axis and Y-axis movable mechanism 10 and the rotation mechanism 9. Furthermore, the chip element 3 mounted on the flexible wiring board 15 using the pin 17 is aligned.
At the same time, the ultrasonic oscillation source 8 is driven to vibrate the diaphragm 5, thereby bringing the chip element 3 and the inner bottom surface of the case 4 into close contact with each other. 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 slowly cooled and hardened.

In the conventional die bonding apparatus shown in FIG. 6, which also serves as positioning, the chip element 3 and the inner bottom surface of the case 4 are brought into close contact only by the weight of the pins 17, but in the die bonding apparatus of this embodiment, Since ultrasonic vibrations are applied to the case 4 in a direction parallel to its inner bottom surface, the molten brazing filler metal 11 is uniformly dispersed on the bottom surface of the chip element 3, as described in the first embodiment, and air bubbles are created in the brazing filler metal 11.・Highly reliable and highly accurate die bonding is possible without leaving any voids.

[0027] In the case of using an adhesive, the first embodiment,
In both of the second embodiments, after applying adhesive to the inner bottom surface of the case 4, the chip element 3 and the electrode terminals 21 of the case 4 are aligned, brought into close contact while applying ultrasonic vibration, and then heated. The plate 6 may be raised to contact the diaphragm 5, and the adhesive may be cured by heating.

[0028]

Effects of the Invention As described above, the present invention provides a heating stage for supporting and fixing and heating a case or other wiring board disposed below an upper mechanism for supporting and fixing a chip element. By providing a diaphragm that supports and fixes the wiring board and an ultrasonic vibration mechanism (an ultrasonic oscillation source and an ultrasonic horn) that causes the diaphragm to vibrate ultrasonically in the horizontal direction, the following effects are achieved. (1) A case or other wiring that is supported and fixed on a heating stage is attached to the bottom surface of a chip element that is suctioned and fixed by the die collet of the upper mechanism, or a chip element that is mounted on a flexible wiring board that is supported and fixed by a micromanipulator. Because the chip element mounting surface of the plate vibrates in parallel with ultrasonic waves, the molten brazing filler metal or adhesive is evenly distributed on the bottom surface of the chip element, resulting in highly reliable die bonding with no bubbles or voids in the brazing filler metal or adhesive. It becomes possible. (2) This allows the chip element sliding stroke for making the chip elements to be in close contact to be extremely smaller than that of the conventional die bonding device using a die collet. Die bonding can be performed by bringing the chips close to the inner wall of the case, and therefore the length of wires for connecting chip elements can be shortened. That is, the inductance component due to the wire can be reduced, which is extremely effective in improving high frequency characteristics. (3) Furthermore, even when die bonding a chip element mounted on a flexible wiring board, 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 aligned. Highly accurate and highly reliable die bonding can be performed without causing problems such as misalignment.

[Brief explanation of the drawing]

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

2 is a longitudinal sectional view illustrating details of the apparatus of FIG. 1 when die bonding a chip element 3 to a case 4; FIG.

FIG. 3 is a longitudinal sectional view illustrating details of die bonding to the case 4 of 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 device.

5 is a longitudinal sectional view illustrating details of die bonding the chip element 3 to the case 4 using the conventional die bonding apparatus shown in FIG. 4. FIG.

FIG. 6 is a perspective view showing a structural example of a flexible wiring board positioning device and die bonding device, which was previously filed by the present inventors.

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

[Explanation of symbols]

1 Die collet 2 Upper mechanism 3 Chip element 4 Case 5 Vibration plate 6 Heat plate 6' Z-axis movable mechanism 7 Ultrasonic horn 8 Ultrasonic oscillation source 9 Rotating mechanism 10 X-axis and 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 and Y-axis movable mechanism 19 Rotation mechanism 20 External lead 21 of flexible wiring board 15
Case 4 electrode terminal

Claims (1)

[Claims] 1. In order to die-bond a chip element such as a bare chip semiconductor element or other surface mount circuit element to a case or other wiring board, an upper mechanism for holding and fixing the chip element, and an upper mechanism arranged at the lower part thereof. A die bonding apparatus comprising a case for die bonding chip elements or a heating stage having a mechanism for holding and fixing another wiring board, wherein the heating stage includes an ultrasonic oscillation source and a case or wiring board for die bonding the chip element. A vibration plate that supports and fixes a plate on an upper surface, and a vibration that horizontally connects the vibration plate to the ultrasonic oscillation source and vibrates the case or wiring board in the horizontal direction by the ultrasonic vibration generated by the ultrasonic oscillation source. a horn, a hot plate that is arranged below the diaphragm and heats the case or wiring board via the diaphragm, a Z-axis moving mechanism that moves the hot plate in a vertical direction, and an ultrasonic oscillation source. and a die bonding apparatus comprising a rotation mechanism and an X-axis and Y-axis movable mechanism that respectively rotate and linearly move the Z-axis movable mechanism within a horizontal plane.