JPH08213398A - Method and device for leveling bump of semiconductor element - Google Patents

Abstract

PURPOSE: To remarkably reduce the time required for performing a bump leveling process so as to shorten the work time of the production of a semiconductor element by leveling the bumps of the element while the element is attracted to and carried by means of a nozzle after the bumps are formed on the electrodes of the element by using gold wires. CONSTITUTION: A capillary 12 driven in the X-, Y-, and Z-directions by means of a capillary driving section 12a forms bumps 3 in a semiconductor element 2 on a bump forming stage 9 by using gold wires. After the bumps are formed, a nozzle 1 attracts the element 2 by suction from the stage 9 and carries the element 2 to a tray 8a. While the element 2 is carried, the bumps 3 are leveled. Namely, the nozzle 1 approaches the element 2 by maintaining the plane 1c of its attracting surface 1b in parallel with the element 2 and makes the height of the bumps 3 uniform by deforming the front end sections of the bumps 3 by bringing the plane 1c into contact with the front ends of the bumps 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bump leveling method for a semiconductor element for leveling the tips of bumps formed on electrodes of the semiconductor element for flip chip mounting of the semiconductor element on a substrate with high density and high reliability. And the device.

[0002]

2. Description of the Related Art A conventional example of a bump leveling method for a semiconductor device in which bumps are formed of gold wires using a wire bonding method will be described with reference to FIGS.

FIG. 10 shows the steps of a conventional bump leveling method for leveling bumps formed of gold wires using the wire bonding method. First, in order to form bumps, the first step # 1 of carrying an IC. In, the semiconductor element is carried into a bump forming apparatus for forming bumps with gold wires,
In the bump forming step # 2, a gold wire is used by a wire bonding method to form the bump 3 by the gold wire on the element electrode of the semiconductor element.

Next, in order to perform bump leveling, in the second step # 13 of carrying the IC, as shown in FIGS. 7 and 8, the semiconductor element 2 bumped using a gold wire by the wire bonding method is mounted. The nozzle 20 adsorbs and conveys to the next process. In this case, the nozzle 20 is the semiconductor element 2
The semiconductor element 2 is adsorbed at a position where it does not contact the bump 3 at all. Reference numeral 10 is an adsorption hole.

In the IC reversing step # 14, the semiconductor element 2 bumped with a gold wire by the wire bonding method is reversed and replaced so that the bumped surface faces down.

In the IC adsorption / conveyance step # 15, the semiconductor element 2 inverted in the previous step is adsorbed by the nozzle 20 and conveyed to another leveling device.

In the leveling step # 16, as shown in FIG. 9, the nozzle 20 attracts the semiconductor element 2 and presses it against the leveling stage 7, whereby the tip of the bump 3 is deformed and the height of the bump 3 is made uniform. Then, the bumps 3 of the semiconductor element 2 are leveled. In this case, the nozzle 20
Is a leveling stage for the semiconductor element 2 while maintaining a parallel state with respect to the leveling stage 7 of the semiconductor element 2 attracted and held by the nozzle 20 by a movement section (not shown) and a control section that controls the movement by this movement section. 7, and is pressed against the leveling stage 7 with a predetermined pressure. The magnitude of pressing is adjusted based on the number of bumps and the like.

[0008]

However, in the structure of the conventional example described above, the bump forming step # 2 and the leveling step # 1 are performed.
6, there is an IC reversing step # 14 in which the bumped semiconductor element 2 is reversed and replaced, and an IC adsorption / conveying step # 15 for moving the bumped semiconductor element 2 to another facility for leveling. Since the leveling itself requires a considerable amount of time, there is a problem that these steps are an obstacle to shortening the manufacturing tact time.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and provide a bump leveling method for semiconductor devices and an apparatus therefor, which reduces the number of steps, shortens the tact time, and is easy to operate.

[0010]

In order to solve the above-mentioned problems, a bump leveling method for a semiconductor device according to a first aspect of the present invention forms a bump on a device electrode of the semiconductor device by a wire bonding method, When the semiconductor element formed with the suction means is sucked and carried out by the suction means, the outer circumference of the suction surface of the suction means that comes into contact with the semiconductor element fits all the device electrodes of the semiconductor element within the outer circumference of the suction surface. And a portion of the suction surface facing the bump is formed in a plane parallel to the semiconductor element, and the parallel state of the plane to the semiconductor element is maintained when the semiconductor element is suctioned by the suction means. At the same time, the suction means is brought close to the semiconductor element, and the plane is brought into contact with the tips of the bumps in the parallel state to deform the tips of the bumps. Wherein the equalizing the height of the flop.

In order to solve the above problems, the semiconductor element bump leveling method according to the second aspect of the present invention is the semiconductor element bump leveling method according to the first aspect of the present invention, wherein a spacer having a predetermined height is provided on the suction surface of the suction means. In addition, when the suction means sucks the semiconductor element, the spacer keeps the flat surface of the suction surface of the suction means parallel to the semiconductor element, and the flat surface and the semiconductor element The feature is that the heights of the leveled bumps are made uniform by keeping the distance constant.

In order to solve the above-mentioned problems, in the bump leveling device for a semiconductor device according to the third aspect of the present invention, all the device electrodes of the semiconductor device are located on the outer periphery of the suction face in contact with the semiconductor device. Adsorption means formed so as to fit within the outer circumference, a plane parallel to the semiconductor element formed at a portion of the adsorption surface facing the bump on the element electrode of the semiconductor element, and the adsorption means attaches the semiconductor element. When sucking, the suction means is brought close to the semiconductor element while maintaining the parallel state of the plane with respect to the semiconductor element, and the plane is brought into contact with the tip of the bump in the parallel state, and the tip of the bump is contacted. And a suction means control section for controlling the suction means movement section.

In order to solve the above problems, a semiconductor element bump leveling device according to a fourth aspect of the present invention is the semiconductor element bump leveling device according to the third aspect of the present invention, wherein the suction surface of the suction means adsorbs the suction means. A spacer having a predetermined height is added to maintain the plane of the surface parallel to the semiconductor element and to keep the distance between the plane and the semiconductor element constant so that the heights of the leveled bumps are equalized. It is characterized by

Further, in the bump leveling device for semiconductor elements according to the fourth aspect of the present invention, in order to solve the above problems, it is preferable that the spacer is a pin provided on the suction surface of the suction means.

Further, in the bump leveling device for a semiconductor device according to the fourth aspect of the present invention, in order to solve the above problems, it is preferable that the spacer is a step provided on the suction surface of the suction means.

[0016]

According to the bump leveling method for a semiconductor element of the first invention of the present application and the bump leveling apparatus for a semiconductor element of the third aspect of the present invention, bumps are formed on the element electrodes of the semiconductor element by the wire bonding method, and the bumps are formed. When carrying out the carried semiconductor device by suction with the suction means, the outer circumference of the suction surface of the suction means that comes into contact with the semiconductor element is set so that all the device electrodes of the semiconductor element fit within the outer circumference of the suction surface. While forming, the portion of the suction surface facing the bump is formed in a plane parallel to the semiconductor element, and while the semiconductor element is sucked by the suction means, while maintaining the parallel state of the plane to the semiconductor element. The suction means is brought close to the semiconductor element, and the plane is brought into contact with the tips of the bumps in the parallel state to deform the tips of the bumps. Since equalizing the height of the lamp is performed in the prior art, reversal of the semiconductor element after bump formation,
There is no need for leveling in a separate leveling facility,
It is possible to significantly reduce the process and shorten the tact time.

The bump leveling method for a semiconductor device according to the second aspect of the present invention and the bump leveling device for a semiconductor element according to the fourth aspect of the present invention are designed so that the bump surface after the leveling is made uniform and the bump surface of the suction means and the semiconductor. Since there are spacers, pins, and steps on the suction surface of the suction means that keep the distance between elements constant, the height of bumps after leveling is unconditionally uniform without troublesome control, and the operation is easy. In addition, high reliability can be obtained when the semiconductor device is flip-chip mounted on the substrate.

[0018]

EXAMPLE A first example of a bump leveling apparatus using the bump leveling method for a semiconductor device of the present invention will be described.

FIG. 1 is a perspective view showing the external appearance of this embodiment when used in a bump forming apparatus using the wire bonding method.

In FIG. 1 using this embodiment, the nozzle 1 for adsorbing a semiconductor element has the following structure. That is,
As shown in FIG. 3, the outer periphery of the suction surface 1b of the nozzle 1 which is in contact with the semiconductor element 2 is formed so that all the device electrodes 11 of the semiconductor element 2 fit within the outer circumference of the suction surface 1b. Further, a portion of the suction surface 1b facing the bump 3 on the element electrode 11 of the semiconductor element 2 is formed on a plane 1c parallel to the semiconductor element 2. Then, the nozzle 1 is moved in the XYZ directions by the nozzle moving unit 1a, and the movement is controlled by a nozzle control unit (not shown). 10 is a semiconductor element 2 by sucking air
Is a suction hole for sucking.

In this embodiment, bumps are leveled in the step shown in FIG. 2 in FIG.

First, in order to form bumps, I of FIG.
In the C loading step # 1, the tray 8 filled with the semiconductor elements diced from the wafer is stored in the storage box 17 and placed on the tray supply unit 15. The tray 8
Is supplied from the tray supply unit 15 and carried into a predetermined position by the carrying-in means 13. The nozzle 1 for adsorbing / conveying the semiconductor element is moved to the tray 8 at the predetermined position by the nozzle moving unit 1a to adsorb the semiconductor element, and the adsorbed semiconductor element is bumped up to a predetermined position on the bump forming stage 9 for bump formation. The bumps are sequentially conveyed in accordance with the bump forming operation of the bump forming step # 2.

In the bump forming step # 2, the bump forming stage 9 is moved in the XY directions by the stage moving section 9a, and in combination with this movement, the capillary driving section 1 is moved.
The capillary 12 driven in the XYZ directions on 2a forms bumps on the semiconductor element on the bump formation stage 9 using a gold wire.

Then, in order to perform bump leveling, I
In the C transport / leveling process # 3, the nozzle 1 is moved to the position shown in FIG.
The semiconductor element 2 having the bumps 3 formed thereon as shown in FIG.
1 from the bump forming stage 9 by suction.
Transport to a. When the tray 8a is full, the unloading means 1
The tray 4 is stored in the tray storage box 17 of the tray unloading section 16.

In this embodiment, the bumps 3 are transferred during this carrying operation.
Leveling. That is, the nozzle 1 is the semiconductor element 2
While maintaining the parallel state of the flat surface 1c of the suction surface 1b with respect to the semiconductor element 2, the flat surface 1c is brought into contact with the tips of the bumps 3 in the parallel state to deform the tip portions of the bumps 3, The heights of the bumps 3 are made uniform. In this case, the force for deforming the tip portion of the bump 3 is the suction force of the nozzle 1 and the pressing force for moving the nozzle 1 in the Z direction, but these controls are performed by a nozzle control unit (not shown). . Then, the pressing control for moving the nozzle 1 in the Z direction and the plane 1c of the nozzle 1 with respect to the semiconductor element 2 are performed.
In order to bring the nozzle 1 closer to the semiconductor element 2 while maintaining the parallel state, the above-described technique in the conventional bump leveling can be used. Then, the magnitude of the pressing force and the magnitude of the suction force may be adjusted based on the configuration of the semiconductor element, the number of bumps to be leveled, and the like.

Comparing the flowchart of the present invention of FIG. 2 with the flowchart of the conventional example of FIG. 10, step #
Although 1 and # 2 are the same, in the present invention, the four steps of steps # 13, # 14, # 15, and # 16 of the conventional example are simplified to one step of step # 3.

Next, a second embodiment of a bump leveling device using the bump leveling method for semiconductor devices of the present invention will be described.

In FIG. 4, when the height of the bumps 3 formed on the element electrodes 11 of the semiconductor element 2 is made uniform by the suction force of the semiconductor element 2 sucked by the nozzle 1 and the force of lowering the nozzle 1. In order to make the height of the bumps 3 uniform to a predetermined height, a spacer 4 having a predetermined height is provided on the suction surface 1b of the nozzle 1. By doing so, the height of the bumps 3 can be made equal to the predetermined height of the spacers 4 regardless of the suction force of the nozzles 1 and the force of lowering the nozzles 1, and the operation becomes easy. In addition, when the semiconductor element 2 is flip-chip mounted on the substrate in the next step, highly reliable mounting becomes possible.

Even if the spacer 4 is a pin 5 as shown in FIG. 5, a notch 6 as shown in FIG. 6 is formed.
Even if it is, the same result is obtained. These selections may be determined according to the surface configuration of the semiconductor element 2.

[0030]

According to the bump leveling method and apparatus for semiconductor elements of the present invention, bumps are formed on the element electrodes of the semiconductor elements by using gold wires, and then these semiconductor elements are adsorbed and conveyed by nozzles. Since the bump leveling is performed by the method, it is possible to significantly reduce the steps and shorten the production takt time as compared with the conventional technology.

Further, by using the spacers which make the heights of the bumps uniform, the bump leveling operation can be simplified and highly reliable mounting can be performed when the semiconductor element is flip-chip mounted. Has the effect.

[Brief description of drawings]

FIG. 1 is a perspective view of a bump leveling apparatus for semiconductor devices using a bump leveling method for semiconductor devices according to the present invention.

FIG. 2 is a flowchart showing an operation of a bump leveling method for a semiconductor device of the present invention.

FIG. 3 is a side view showing a main part of a first embodiment of a bump leveling device for semiconductor devices using the bump leveling method for semiconductor devices of the present invention.

FIG. 4 is a side view showing an example of a main part of a second embodiment of a bump leveling device for semiconductor devices using the bump leveling method for semiconductor devices of the present invention.

FIG. 5 is a side view showing another example of the essential parts of the second embodiment of the bump leveling apparatus for semiconductor devices using the bump leveling method for semiconductor devices of the present invention.

FIG. 6 is a side view showing another example of the main part of the second embodiment of the bump leveling apparatus for semiconductor devices using the bump leveling method for semiconductor devices of the present invention.

FIG. 7 is a diagram showing an operation of a bump leveling method for a semiconductor device of a conventional example.

FIG. 8 is a diagram showing an operation of a bump leveling method for a semiconductor device of a conventional example.

FIG. 9 is a diagram showing an operation of a bump leveling method for a semiconductor device of a conventional example.

FIG. 10 is a flowchart showing an operation of a bump leveling method for a semiconductor device of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Nozzle (adsorption means) 1a Nozzle moving part (adsorption means moving part) 1c Plane 2 Semiconductor element 3 Bump 4 Spacer 5 Pin 6 Notch (step) 8 Tray 8a Tray 9 Bump forming stage 9a Stage moving part 10 Adsorption hole 11 Element Electrode 12 Capillary 12a Capillary drive unit 13 Carrying-in means 14 Carrying-out means 15 Tray supply section 16 Tray carry-out section 17 Tray storage box

Claims (6)

[Claims] 1. A suction means for contacting the semiconductor element when the bump is formed on the element electrode of the semiconductor element by a wire bonding method and the semiconductor element having the bump is adsorbed by the suction means and carried out. The outer periphery of the suction surface is formed so that all the device electrodes of the semiconductor element fit within the outer periphery of the suction surface, and the portion of the suction surface facing the bump is formed in a plane parallel to the semiconductor element. Then, when the semiconductor element is sucked by the suction means, the suction means is brought close to the semiconductor element while maintaining the parallel state of the plane to the semiconductor element, and the plane is brought into contact with the tip of the bump in the parallel state. A bump leveling method for a semiconductor device, characterized in that the tips of the bumps are deformed to make the heights of the bumps uniform. 2. The bump leveling method according to claim 1, wherein a spacer having a predetermined height is added to the suction surface of the suction means, and when the suction means sucks a semiconductor element, the spacer causes the suction means to move. Maintaining a flat surface of the suction surface of the semiconductor element in parallel with the semiconductor element, and maintaining a constant distance between the flat surface and the semiconductor element so that the height of each leveled bump is uniform. Bump leveling method for semiconductor devices. 3. In a device for leveling bumps of a semiconductor device having bumps formed on the device electrodes by a wire bonding method, all the device electrodes of the semiconductor device are provided on the outer periphery of a suction surface in contact with the semiconductor device. A suction means formed so as to fit within the outer periphery of the suction surface, a plane parallel to the semiconductor element formed on a portion of the suction surface facing the bump on the element electrode of the semiconductor element, and the suction means. When adsorbing the semiconductor element, the adsorption means is brought close to the semiconductor element while maintaining the parallel state of the plane with respect to the semiconductor element, and the plane is brought into contact with the tip of the bump in the parallel state, And a suction means control section for controlling the suction means movement section for deforming the tip of the bump to make the height of each bump uniform. A bumper leveling device for semiconductor devices. 4. The bump leveling device for a semiconductor element according to claim 3, wherein a flat surface of the suction surface of the suction means is maintained parallel to the semiconductor element on the suction surface of the suction means. A bump leveling device for a semiconductor device, characterized in that a spacer having a predetermined height is added to maintain a constant distance from the semiconductor device and to make the height of each leveled bump uniform. 5. The bump leveling device for a semiconductor element according to claim 4, wherein the spacer is a pin provided on the suction surface of the suction means. 6. The bump leveling device for a semiconductor device according to claim 4, wherein the spacer is a step provided on the suction surface of the suction means.