JP2002252253A - Method and apparatus for jointing component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for jointing a component and its jointing apparatus by which a product failure caused when a component is jointed by effecting an ultrasonic vibration can be decreased compared with the past. SOLUTION: When jointing a semiconductor chip 150 and a circuit substrate 20 through a bump 11 together, a major vibration direction 97 of the ultrasonic vibration is obtained from a controlling device 110 on the basis of at least one factor among a number of the bump, a location of the bump, a material of the bump, and a height of the bump, and a piezoelectric element 91 is directed in the major vibration direction and is subjected to the ultrasonic vibration. Thereby, friction effected to each bump is almost uniformed, a deterioration of joint strength caused from a mispositioning of semiconductor chip and a reduction of contact area of bump can be prevented, and the occurrence of product failure can be more reduced compared with the past.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flip chip in which an electronic component such as a so-called bare chip cut from a semiconductor wafer is directly mounted on a circuit board via a bump, for example, and subjected to ultrasonic vibration to join the flip chip. The present invention relates to a component joining method and device applicable to mounting and the like.

[0002]

2. Description of the Related Art In recent years, as electronic devices have become smaller and lighter and electronic components used in the devices have been operated at higher frequencies, flip-chip mounting in which electronic components are directly mounted on a circuit board and joined has been used. I have. Above all, when a micro device such as a SAW filter or a crystal oscillator is mounted on a package substrate, by applying ultrasonic vibration to the micro device, the package is formed via a bump formed on the micro device or the package substrate. An ultrasonic bonding flip-chip mounting method for bonding the above-described micro device on a substrate is often used.

[0003] FIG. 16 shows a head 2 and a recognizing device 6 as main components of a component bonding device 30 for bonding the microdevice on the package substrate.
And a stage 8 are shown. The head 2 holds the electronic component 1 corresponding to the micro device, and after positioning the electronic component 1 at a bonding position on the circuit board 9, places the held electronic component 1 on the circuit board 9. This is a device for joining the electronic components 1 while pressing the electronic components 1 with ultrasonic waves. Therefore, the head 2 has an ultrasonic vibration generator 3 for generating the ultrasonic vibration, and the electronic component 1
A nozzle 4 having a holding portion 4a for sucking and holding the nozzle, and being attached to the ultrasonic vibration generating portion 3, and a rotating device 5 for rotating the ultrasonic vibration generating portion 3 and the nozzle 4 in the circumferential direction of the nozzle 4. Have. The head 2 is moved, for example, in the X direction by a moving device (not shown).

[0006] The circuit board 9 is mounted on the stage 8, and the stage 8 has a structure movable in, for example, the Y direction. The recognition device 6 includes an imaging camera that recognizes the attitude of the electronic component 1 held by the holding unit 4a, and imaging information is displayed on the display unit 7. The head 2 and the stage 8 move in the X and Y directions based on the imaging information so that the electronic component 1 held by the holding unit 4a is joined to the joining position on the circuit board 9.

[0005] A conventional electronic component joining method using the component joining apparatus 30 having the above-described configuration will be described. Head 2
Moves to the component holding position, and the electronic component 1 is sucked and held by the holding unit 4a. Next, the electronic device 1 held by the holding unit 4a is recognized by the recognition device 6, and the position and angle of the held electronic component 1 are detected. In this way, the position of the electronic component 1 is corrected by operating the head 2 and the rotating device 5 based on the recognition result. Then, the electronic component 1 is mounted on the bonding position on the circuit board 9 and further pressed. At this time, the ultrasonic vibration generating unit 3 is operated to apply ultrasonic vibration to the electronic component 1 via the nozzle 4 and the holding unit 4a. By the action of the pressing operation and the ultrasonic vibration, the bump 11 shown in FIG. 17 joined to the electronic component 1 and the electrode portion 10 on the circuit board 9 are joined by the metal diffusion phenomenon of both.

[0006]

By the way, before applying the ultrasonic vibration, the ultrasonic vibration is applied to the electronic component 1 at the mounting position at the time when the bump 11 is brought into contact with the electrode portion 10. Accordingly, the electronic component 1 may be moved to a position shifted from the mounting position and joined. This is caused when the arrangement of the bumps 11 is not symmetrical with respect to the vibration direction of the ultrasonic vibration, and the balance of the frictional force at each bump 11 is lost when the bonding proceeds. For example, as shown in FIG. 20, this case corresponds to a case where the above ultrasonic vibration is applied to the electronic component 1 having three bumps 11 along the direction of the arrow 14. When the displacement of the electronic component 1 is large, the product after bonding may be defective.

[0007] On the other hand, there are cases where measures are taken to find the joining conditions that maintain the joining strength as much as possible and prevent the displacement of the joining position. Not always available. Generally, by suppressing the amplitude of the ultrasonic vibration, the displacement of the joining position is reduced, but this causes a decrease in the joining strength. That is, it can be said that increasing the joining strength and suppressing the displacement of the joining position are in a contradictory relationship.

Before bonding, the circular bump 11
When they are joined by applying ultrasonic vibration, they usually deform into an elliptical shape. Therefore, when the electronic component 1 is mounted on the circuit board 9 and the bumps 11 are located on the periphery of the electrode portion 10 of the circuit board 9 as shown in FIG. As a result, as shown in FIG. 19, the bump 1 bonded to the end of the electrode portion 10 of the circuit board 9
1 may reach the wiring pattern adjacent to the electrode portion 10 and cause an electrical short, resulting in a defective product. Even when the short circuit does not occur, the bump 11 is deformed by the
In some cases, the bonding strength may be reduced due to a reduction in the bonding area of the bumps 11 and the product may be defective. In these cases as well, while maintaining the bonding strength as much as possible, a bonding condition that prevents the deformation of the bump 11 may be sought, and countermeasures may be taken. However, the bonding condition that suppresses the defect to zero is not always obtained.

As described above, in the conventional electronic component bonding method, there is a problem that the bonding position of the electronic component is shifted, a short circuit is caused by the deformation of the bump, and the bonding strength is reduced, resulting in a defective product. In addition, there is a problem that it takes a long time to find bonding conditions for preventing the occurrence of product defects, and there is also a problem that, depending on the obtained conditions, bonding strength is reduced and product defects occur. The present invention has been made in order to solve such a problem, and when performing component bonding by applying ultrasonic vibration, a component bonding method capable of reducing the occurrence of product defects as compared with the related art, and An object of the present invention is to provide a component joining apparatus that executes the component joining method.

[0010]

According to a first aspect of the present invention, there is provided a component bonding method for bonding an electrode of an electronic component and an electrode portion of a circuit forming body via a bump. The method is characterized in that the bonding is performed after changing the vibration direction of the ultrasonic vibration to be applied in the direction to prevent the displacement of the bump.

Further, the vibration direction is obtained based on at least one of the number of the bumps, the position of the bumps, the material of the bumps, and the height of the bumps. The bonding may be performed while relatively ultrasonically vibrating the circuit forming body along the vibration direction.

When the vibration direction is determined based on the arrangement position of the bumps, the vibration direction may be determined as a direction along an axis of symmetry that makes the arrangement of the bumps substantially symmetric.

Further, the vibration direction may be a direction in which the bumps are joined by the ultrasonic vibration in the region of the electrode or the electrode portion.

Further, a component bonding apparatus according to a second aspect of the present invention includes a bump bonding apparatus for bonding an electrode of an electronic component and an electrode portion of a circuit forming body via a bump, and a bump bonding apparatus for performing the bonding operation by the bump bonding apparatus. An ultrasonic vibration generator that relatively ultrasonically vibrates the electronic component and the circuit forming body along the vibration direction, and the number of the bumps, the arrangement position of the bumps, the material of the bumps, and the height of the bumps And a control device for determining the vibration direction based on at least one of the elements, and causing the ultrasonic vibration generator to generate ultrasonic vibration along the determined vibration direction.

[0015] In the second aspect, when the bump bonding apparatus has a configuration in which the ultrasonic vibration generating device is attached to a nozzle having a holding member having the same size as the electronic component attached to a tip end thereof, The joining device further includes a rotating device that rotates the ultrasonic vibration generating device in a circumferential direction of the nozzle, and the control device controls the rotation by the rotating device to control the ultrasonic vibration generating device. The ultrasonic vibration generator is arranged along the vibration direction to generate ultrasonic vibrations along the vibration direction, and the ultrasonic vibration generator can hold the electronic component against rotation by the rotating device. It is also possible to have a mounting change mechanism for changing the mounting of the nozzle to an appropriate posture.

Further, in the second aspect, it is possible to further comprise an imaging device for imaging the holding member, and a monitor for visually displaying the imaging information.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A description will be given below of a component joining method according to an embodiment of the present invention and a component joining apparatus for executing the component joining method with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals.
In this specification, the term "circuit-forming body" refers to a circuit board such as a resin board, a paper-phenol board, a ceramic board, a glass epoxy (glass epoxy) board, a film board, a circuit board such as a single-layer board or a multilayer board, or a component. , A housing, a frame or the like, on which a circuit is formed. still,
In the present embodiment, a circuit board is taken as an example. In this embodiment, a semiconductor chip cut from a semiconductor wafer is taken as an example of an electronic component. Further, in the present embodiment, bumps made of gold are formed on the electrodes of the semiconductor chip. However, the electronic component and the member on which the bump is formed are not limited to the above-described case.

As shown in FIG. 1, the component bonding apparatus 101 of the above embodiment is roughly divided into a component supply apparatus 102, a bonding stage 103 as an example that functions as a circuit formed body holding apparatus, a component reversing apparatus 104, Bump bonding device 105, circuit board transfer device 106, imaging device 1
24, and a control device 110. In the component supply apparatus 102, a bump 112 is formed on an electrode of an integrated circuit formed on a semiconductor wafer, and a wafer 112 scribed for each integrated circuit is placed in a magazine lifter 111.
Supplied from The component supply apparatus 102 is an apparatus that performs so-called stretching of the wafer 112, divides the wafer 112 into individual semiconductor chips on which the integrated circuit portions are formed, and supplies the semiconductor chips 150 cut from the wafer 112 by the division. It is. In the present embodiment, FIG.
The bumps 11 are formed on the electrodes 13 of the semiconductor chip 150 as shown in FIG. In this embodiment, the diameter dimension I of the bump 11 is about 100 μm,
Base portion 11 on electrode 13 of semiconductor chip 150
a is about 30 to 35 μm, and the total height I is
I is about 70-75 μm. As will be described later, the bump 11 is pressed by the electrode portion 21 of the circuit board 20, but the crushed bump after pressing (hereinafter, the crushed bump 1) is pressed.
1 is given a shape as shown in FIG. 10 and the height IV of the bump 12 is substantially equal to the height III of the base portion 11a.

The states of the wafer 112 and the individual semiconductor chips 150 supplied to the component supply device 102 are as follows:
An image is captured by the wafer recognition device 113 installed above the component supply device 102, and the captured image information is supplied to the control device 110. Note that, as described above, in the present embodiment, the above-described semiconductor chip is taken as an example of the electronic component. Therefore, the component supply device 102 having such a form is provided. Naturally, the form of the component supply device is also changed.

The circuit board transport device 106 is a device for loading and unloading the circuit board 20 from and to the component joining device 101. The bonding stage 103 is a stage for mounting the circuit board 20 carried in by the circuit board transfer device 106 and performing bump bonding.
As shown in FIG. 1, a Y-axis robot 107 having a so-called ball screw structure and having a motor 114 as a drive unit slides in the Y direction. Also, the bonding stage 10
In order to mount the circuit board 20 on the bonding stage 103 in accordance with the size of the circuit board 20 supplied from the circuit board transport device 106, the peripheral portion of the circuit board 20 along the Y direction is It has a board setting part 115 that is held and movable in the X direction, and a board setting part 116 that holds a peripheral portion of the circuit board 20 along the X direction and is movable in the Y direction. Further, a suction passage for sucking and holding the circuit board 20 is formed in the bonding stage 103, and the suction passage communicates with the suction device 117. In addition, the circuit board 20 is about 15
A heating device 118 for heating to 0 ° C. is provided.

In the wafer 112, the circuit forming portion having the bumps 11 naturally faces upward. Then, each of the divided semiconductor chips 150 is
After being pushed up in the thickness direction of the semiconductor chip 150 by the push-up device 120 provided in the component supply device 102,
The parts are held one by one by the component reversing device 104. The component reversing device 104 holds the semiconductor chip 150 from the component supply device 102 and holds the electrode 13 of the semiconductor chip 150.
This is an apparatus for inverting the held semiconductor chip 150 such that the bump 11 formed on the semiconductor substrate 150 faces the circuit board 20 mounted on the bonding stage 103.

The bump bonding apparatus 105 receives the semiconductor chip 150 from the component reversing apparatus 104, conveys the semiconductor chip 150 to the bonding stage 103, and then holds the semiconductor chip 150 at a predetermined position on the circuit board 20 mounted on the bonding stage 103. Pressing the semiconductor chip 150 in the Z direction and applying ultrasonic vibration to the bump 1
1 is a device for joining the circuit board 1 to the electrode section 21 of the circuit board 20.
As shown in FIGS. 2 and 12, the joining device 105 includes a component holding device 96 that holds the semiconductor chip 150 and a voice coil motor (VCM) 121 that presses the semiconductor chip 150 onto the circuit board 20 via the bump 11. And an ultrasonic vibration generator 9 having a piezoelectric element 91 for ultrasonically vibrating the semiconductor chip 150 in the main vibration direction in the present embodiment when the voice coil motor 121 performs a pressing operation.
And one of the characteristic components in the present embodiment, and based on the control of the control device 110, the following nozzle 93
In the circumferential direction of the piezoelectric element 9 (sometimes referred to as the θ direction).
And a rotation device 122 for rotating the rotation device 1. The piezoelectric element 91 is connected to the control device 110 via the oscillator 133.

As shown in FIG. 12, in the present embodiment, the component holding device 96 has the same shape and the same size as the semiconductor chip 150 to be held.
And a nozzle 93 having a suction passage 94 formed along the axial direction for holding the semiconductor chip 150 by suction in the present embodiment. And a suction device 119 that communicates with the passage 94 and is operationally controlled by the control device 110. In addition, the method of holding the semiconductor chip 150 is not limited to the above-described suction operation, and may be configured to mechanically hold the semiconductor chip 150, for example.

The reason why the holding member 95 has the same shape and the same size as the semiconductor chip 150 to be held is as follows. That is, when the holding member 95 is smaller than the semiconductor chip 150 to be held, ultrasonic vibration is not transmitted to the entire semiconductor chip 150, so that a problem that the bonding strength is deteriorated may occur. Conversely, when the holding member 95 is large with respect to the semiconductor chip 150 to be held, the semiconductor chip 150 and the semiconductor chip contact surface of the holding member 95 are rubbed by ultrasonic vibration. In some cases, the semiconductor chip 150 may be worn and a depression having the same shape as the semiconductor chip 150 may be formed on the semiconductor chip contact surface. Therefore, when the semiconductor chip 150 is displaced on the semiconductor chip contact surface, the semiconductor chip 15
This is because a local load may act on the semiconductor chip 150 to damage the semiconductor chip 150. Therefore, it is preferable that the holding member 95 has the same shape and the same size as the semiconductor chip 150 to be held.

In the present embodiment, the voice coil motor joins the bumps 11 and the electrode portions 21 of the circuit board 20 with each other.
The semiconductor chip 150 is moved in a direction in which the bumps 11 and the electrode portions 21 approach each other (Z direction in the present embodiment) so that the bumps 11 are opposed to each other, and the bumps 11 and the electrode portions 21 are pressed.

The ultrasonic vibration generator 9 generates frictional heat between the bumps 11 and the electrode portions 21 on the circuit board 20 side to reduce the heating temperature of the bonding stage 3 and to reduce the temperature of the bumps 11. This is an apparatus for generating ultrasonic vibration for vibrating the bump 11 in order to strengthen the bonding of the bumps. The ultrasonic vibration generating device 9 is shown in FIG.
As shown in FIG. 2, a piezoelectric element 91 having a plurality of layers and an ultrasonic horn 92 to which the piezoelectric element 91 is connected at one end are provided. When a voltage is applied to these piezoelectric elements 91,
Ultrasonic vibration is generated along a main vibration direction 97 corresponding to the laminating direction of the piezoelectric elements 91. The generated main vibration direction 9
The vibration to 7 is amplified by the ultrasonic horn 92. At the other end of the ultrasonic horn 92, a nozzle 93 provided at the tip with the holding member 95 for holding the semiconductor chip 150 is attached, and by the vibration of the piezoelectric element 91,
The nozzle 93, that is, the semiconductor chip 150 held by the holding member 95 vibrates ultrasonically in the main vibration direction 97.
The piezoelectric element 91 vibrates in the main vibration direction 97,
In the process of transmitting the generated vibration to the semiconductor chip 150, vibrations in various directions actually occur. Therefore,
In the semiconductor chip 150, the main vibration direction is the main vibration direction 97, but it actually vibrates in various directions.

In the component bonding apparatus 101, after the bumps 11 of the semiconductor chip 150 are pressed against the circuit board 20 heated to about 150 ° C. by the bonding stage 103, The bump 11 is ultrasonically vibrated to generate frictional heat between the bump 11 and the electrode portion 21 to perform the bonding.

Next, the rotating device 122 will be described. As described with reference to FIG. 20, when the arrangement of the bumps 11 is not symmetric with respect to the vibration direction of the ultrasonic vibration,
When the bonding progresses, the balance of the frictional force at each bump 11 is lost, so that the electronic component 1 may move to a position shifted from the mounting position and be bonded. Further, as described with reference to FIG. 19, depending on the direction of the ultrasonic vibration to be applied, the bump 11 reaches the wiring pattern adjacent to the electrode portion 10 and causes an electrical short. In some cases, the joint strength may be reduced due to the decrease in the joint area of No. 11.

In this embodiment, in order to solve such a problem, the semiconductor chip 1 which is an example of an electronic component is used.
With respect to 50, the main vibration direction 97 of the ultrasonic vibration applied when performing the joining is changed to a direction for preventing the displacement of the bump 11. More specifically, the main vibration direction 97 is determined according to the number of bumps 11, the arrangement position of the bumps 11, the material of the bumps 11,
And the height of the bump 11 is determined based on at least one element. In the present embodiment, the determined main vibration direction 9 is determined.
The above-described bonding is performed while ultrasonically oscillating the semiconductor chip 150 along 7. This is one semiconductor chip 150
This is because the number, arrangement position, and height of the bumps 11 described above may cause a loss of the balance of the frictional force of each bump 11 at the time of joining by applying ultrasonic vibration. Further, for example, in an LED (light emitting diode), the materials of the two electrode portions may be different, for example, such as aluminum and gold. Therefore, due to the difference in the material of the bump 11 made of, for example, gold and the electrode portion, the time required for the completion of the joining and the joining strength differ between the bumps 11. As described above, the material of the bumps 11 is also a factor that breaks the balance of the frictional force.

Therefore, for example, a power module IC,
GMR attached to the tip of the hard disk head
(Giant Magneto Resistive: Giant Magneto-Resistive Effect) In a case where there is a bias in the arrangement position of the bumps 11 as in the case of a head, and when the main vibration direction 97 is obtained based on the arrangement position of the bump 11, the main vibration direction 97 , The direction along the axis of symmetry that makes the arrangement of the bumps 11 substantially symmetrical. More specifically, for example, as shown in FIG. 5, when the bump 11 exists at each vertex of a quadrangle, the symmetry axes are denoted by reference numerals 971-1 to 971-
Four axes, denoted by 4, are possible. Therefore, the main vibration direction 97 is a direction along any one of these symmetry axes 971-1 to 971-4. Also, for example, as shown in FIG. 6, when the bumps 11 are present at the apexes of a triangle, if the ultrasonic vibration is performed in the direction indicated by reference numeral 973, the number of bumps is large in the state where the bonding is in progress. The joining strength on the upper side of the drawing is higher than that on the lower side.
When further ultrasonic vibration is applied in this state, the semiconductor chip 150 and the holding member 95 slide on the upper side where the bonding strength is strong, whereas the bump 11 in contact with the circuit board 20 vibrates on the lower side. Become. As a result, the semiconductor chip 150 may be displaced in the rotation direction with one of the upper two bumps 11 as a fulcrum. On the other hand, when the ultrasonic vibration is applied in the 45-degree direction indicated by reference numeral 972, each of the bumps 11 vibrates while maintaining the bonding strength balance while the bonding is in progress.
No displacement of the semiconductor chip 150 occurs. Therefore, as the symmetry axis, the one indicated by reference numeral 972 can be considered.
The main vibration direction 97 is a direction along the axis of symmetry 972.

When the electrical short-circuit or the decrease in the bonding strength due to the reduction of the bonding area of the bump 11 is caused, the main vibration direction 97 is set to the direction of the electrode 13 or the electrode portion 21.
Is the direction in which the bumps 11 are joined by the ultrasonic vibration in the region of FIG. Specifically, for example, as shown in FIG. 7, when the bump 11 is located at the periphery of the electrode portion 21, the deformation of the bump 11 due to the ultrasonic vibration does not protrude from the region of the electrode portion 21. The direction indicated by the arrow 973 is the main vibration direction 97.

The control device 110 includes position information of the bumps 11 on the semiconductor chip 150 relating to the bonding operation,
The control device 110 stores bonding information necessary for the bonding operation, such as information on the position and size of the electrode portion 21 on the circuit board 20 to which the semiconductor chip 150 is bonded, and information on the arrangement of the bumps 11 with respect to the electrode portion 21. Can automatically determine the main vibration direction 97 based on the bonding information. Alternatively, the main vibration direction 97 is controlled by the control device 11.
It is also possible for an operator to input 0, and it is also possible to configure the system to supply the information via a communication line.

In the situation where the main vibration direction 97 is determined as described above, the rotating device 122 is connected to the piezoelectric element holding member 1221 for holding the piezoelectric element 91 and extends in the Z-axis direction as shown in FIGS. The piezoelectric element holding member 1221 is rotated in the circumferential direction (θ direction) 1222 of the nozzle 93 that is present, and the operation is controlled by the control device 110. A transmission mechanism 1224 for transmitting the power of the portion 1223 to the piezoelectric element holding member 1221.

With such a configuration, the control device 11 is controlled so that the lamination direction of the piezoelectric elements 91 is along the main vibration direction 97.
0, the drive unit 1223 operates, and the transmission mechanism 1
The piezoelectric element holding member 1221 rotates in the circumferential direction (θ direction) 1222 via 224. Therefore, the piezoelectric element 91 held by the piezoelectric element holding member 1221 and the ultrasonic horn 92 attached to one end of the piezoelectric element 91
Also rotates in the circumferential direction 1222. As described above, in the present embodiment, the laminating direction of the piezoelectric elements 91 can be aligned with the main vibration direction 97 by the rotating device 122 and the control device 110. Therefore, the electronic component 1 does not move and be bonded to a position shifted from the mounting position, and the electrical short circuit and the reduction in bonding strength due to a reduction in the bonding area of the bump 11 do not occur. Can be reduced as compared with the related art.

On the other hand, the rotation of the piezoelectric element 91 causes the nozzle 93 attached to the other end of the ultrasonic horn 92 and the holding member 95 fixed to the nozzle 93.
Also rotates in the circumferential direction 1222. In the present embodiment, as described above, the holding member 95 holds the semiconductor chip 15 to be held.
As shown in FIG. 13, when the holding member 95 rotates in the circumferential direction 1222 so that the holding member 95 attempts to hold the semiconductor chip 150 from the component reversing device 104 because the holding member 95 rotates in the circumferential direction 1222. As described above, the holding member 95 and the semiconductor chip 150 may be misaligned. Therefore, in the present embodiment, as shown in FIG. 4, the holding member 95 can hold the semiconductor chip 150 independently of the ultrasonic horn 92 of the piezoelectric element 91 held by the piezoelectric element holding member 1221. The ultrasonic horn 92 is provided with a mounting change mechanism 98 that allows the direction of the holding member 95, that is, the mounting of the nozzle 93 to be changed.

In the present embodiment, as shown in the drawing, the mounting change mechanism 98 is provided in a nozzle mounting hole 921 provided in the ultrasonic horn 92 and through which the nozzle 93 is inserted.
Is formed by a fastening mechanism having a fixing screw 922 for pressing the pressure. The structure of the attachment changing mechanism 98 is not limited to the above-described embodiment, but may be a known fastening structure. Therefore, after rotating the piezoelectric element holding member 1221 in the circumferential direction 1222 by the rotating device 122 so that the lamination direction of the piezoelectric elements 91 is along the main vibration direction 97, the fixing screw 922 is loosened. The nozzle 93, that is, the holding member 95, can be freely rotated in the circumferential direction 1222 with respect to the ultrasonic horn 92 held by the piezoelectric element holding member 1221 via the piezoelectric element 91. Therefore, the direction of the holding member 95 can be changed according to the direction of the semiconductor chip 150 held by the holding member 95. In the bump bonding apparatus 105, the nozzle 93 is mounted in a structure that can freely rotate in the circumferential direction 1222.

In the above description, the piezoelectric element holding member 122 is set in a state where the nozzle 93 is attached to the ultrasonic horn 92 in advance.
1, the piezoelectric element 91 and the ultrasonic horn 92 were rotated in the circumferential direction 1222. However, when the nozzle 93 was not mounted on the ultrasonic horn 92, the piezoelectric element holding member 1221 was rotated.
After the piezoelectric element 91 and the ultrasonic horn 92 are rotated in the circumferential direction 1222 through the above, the ultrasonic horn 92 is moved from the component reversing device 104 to the ultrasonic horn 92 so that the holding member 95 is in a posture capable of holding the semiconductor chip 150. Alternatively, the nozzle 93 may be mounted, and the mounting may be completed with the fixing screw 922 of the mounting change mechanism 98. In the following description of the operation of the joining method, a method of attaching the nozzle 93 later will be described.

The bump bonding apparatus 1 configured as described above
In step 05, the X-axis robot 108 is moved in the X-axis direction. The X-axis robot 108 has a so-called ball screw structure as shown in FIG.
Has a motor 123 as a drive unit whose operation is controlled by the control unit. Therefore, when bonding the semiconductor chip 150 held by the bump bonding apparatus 105 to the circuit board 20 held on the bonding stage 103, the X-axis robot 108 controls the position in the X-axis direction, The position of the bonding stage 103 in the Y-axis direction is controlled by the Y-axis robot 107, and the bumps 1 formed on the electrodes 13 of the semiconductor chip 150 are formed.
1 and the electrode portion 21 of the circuit board 20 can be arranged facing each other.

The imaging device 124 includes the holding member 95
In order to recognize the amount of rotation in the circumferential direction 1222 in the above, the semiconductor chip 1 held by the holding member 95
In order to recognize the displacement of the holding member 95, the holding member 95 is imaged and recognized from underneath.
1 and the image recognition unit 124 included in the control device 110
2 and a monitor 1243 for displaying a captured image. Further, a moving device for moving the imaging camera 1241 to a position where the holding member 95 can image can be provided. As described above, after rotating the piezoelectric element holding member 1221 in the circumferential direction 1222 by the rotating device 122, the orientation of the holding member 95 is changed according to the orientation of the semiconductor chip 150 held by the component reversing device 104. Although it is necessary to change the rotation, the rotation of the holding member 95 in the circumferential direction 1222 for changing the direction is monitored by recognizing the posture of the holding member 95 by the imaging device 124 and displaying the posture on the monitor 1243. It can be done while checking the video. Therefore, the monitor 124
Reference numeral 3 denotes a position where the operator can visually check the ultrasonic horn 92 while attaching the nozzle 93 to the ultrasonic horn 92.

The control device 110 controls the operation of each of the devices described above, for example, the component supply device 102 and the bonding stage 103. When the control device 110 is classified according to its function, the control device 110 includes a main processing unit 1101, a memory unit 1102, a motor control unit 1103, a load control unit 1104, and the image recognition unit 1242 as shown in FIG. The memory unit 1102 stores various information including the above-described bonding information. The motor control unit 1103 controls the motor 12 of the X-axis robot 108.
3. Y-axis robot 107 for bonding stage 103
, The operation control of the motor 114, the voice coil motor 121 of the bump bonding device 105, and the driving unit 1223 of the rotating device 122. Therefore, the rotating device 1
In the rotation of the piezoelectric element 91 in the circumferential direction 1222 in the main vibration direction 97 by the motor 22, the main vibration direction 97 is obtained by the main processing unit 1101, and the motor control unit 1103
The operation of the driving unit 1223 of the rotating device 122 is controlled by the control of. The load control unit 1104 controls the pressing force generated by controlling the current supplied to the voice coil motor 121. In the present embodiment, one control device 110 is provided in the whole of the component bonding device 101 and controls, for example, a bump bonding operation. However, it is needless to say that a control device is individually provided for each device. Can also.

Next, the semiconductor chip 150 and the circuit board 2 are connected by the component bonding apparatus 101 having the above configuration.
The method of joining with 0 will be described below with reference to FIG. The joining method is executed based on operation control of the control device 110. First, the steps (“S” in the figure)
1), the control device 110, as described above,
The main vibration direction 97 is obtained based on the bonding information on the semiconductor chip 150 and the circuit board 20 to be bonded. Then, the rotating device 122 of the bump bonding device 105 is arranged such that the lamination direction of the piezoelectric element 91 and the ultrasonic horn 92 are along the obtained main vibration direction 97.
The operation of the drive unit 1223 is controlled to rotate the piezoelectric element 91 and the ultrasonic horn 92 in the circumferential direction 1222 via the piezoelectric element holding member 1221. Here, the nozzle 93 is not mounted on the ultrasonic horn 92 in the rotation operation.

In the next step 2, the parts reversing device 104
The nozzle 93 is attached to the ultrasonic horn 92 so that the holding member 95 matches the component holding angle which is an angle at which the semiconductor chip 150 can be held from the above.
8 to the ultrasonic horn 92 with the fixing screw 922 of the nozzle 9
3 is fixed. In the operation of attaching the nozzle 93 to the ultrasonic horn 92, the imaging camera 12 of the imaging device 124
41 is moved to the position where the image of the holding member 95 can be picked up, and while the orientation of the holding member 95 is visually checked on the monitor 1243, the holding member 95 is set so as to have the component holding angle. Fixing the nozzle 93 to the ultrasonic horn 92 at 922 is preferable from the viewpoint of workability.

In the next step 3, a series of operations for mounting the semiconductor chip 150 at the bonding position on the circuit board 20 held on the bonding stage 103 is started. In the next step 4, after holding the semiconductor chip 150 from the component supply device 102 by the component reversing device 104,
It is turned upside down and transported to the component holding position. on the other hand,
The bump joining device 105 is also moved to the above-mentioned component holding position by the X-axis robot 108. In the next step 5, the operation of the driving unit 1223 of the rotating device 122 of the bump bonding device 105 is controlled again to control the operation of the piezoelectric element holding member 122.
1, the piezoelectric element 91 and the ultrasonic horn 92 are rotated in the circumferential direction 1222. As described above, the rotation operation has already been executed in step 1, but the piezoelectric element 91 and the ultrasonic horn 92 have returned to the origin by a series of operations, or in the continuous operation, the angle was set to the angle in the previous mounting. Since it has been left, it is also executed in step 5.

In the next step 6, the inverted semiconductor chip 150 is placed in the bump bonding apparatus 1 at the component holding position.
05 is held from the component reversing device 104 by the holding member 95. At this time, the holding member 95
Of the semiconductor chip 150 held by the component reversing device 104, the holding member 95 and the semiconductor chip 1 are oriented as shown in FIG.
There is no misalignment with 50.

In the next step 7, the X-axis robot 1
At 08, the bump bonding apparatus 105 is moved to above the imaging camera 1241 of the imaging apparatus 124, and at step 8, the imaging camera 1241 images the holding posture of the semiconductor chip 150 held by the holding member 95. In the next step 9, the held semiconductor chip 150
The minute position correction of the semiconductor chip 150 is executed based on the imaging information of the holding posture so that the semiconductor chip 150 can be accurately attached to the bonding position. That is, the piezoelectric device holding member 1221 and the ultrasonic horn 9 are
The rotation amount in the circumferential direction 1222 of the holding member 95 at the tip end of the nozzle 93 through the nozzle 2 is controlled, and the X-axis robot 108 and the Y-axis robot 107 are controlled.
Is moved in the X and Y directions.

In step 10, the semiconductor chip 150 held by the holding member 95 is mounted on the circuit board 20 held by the bonding stage 103 at a bonding position by the bump bonding apparatus 105. In the next step 11, the piezoelectric element 91 is operated to apply ultrasonic vibration to the semiconductor chip 150 held by the holding member 95 while being pressed by the voice coil motor 121, and Semiconductor chip 150
To the circuit board 20.

As described above, the vibration direction of the ultrasonic vibration applied to the semiconductor chip 150 at the time of bonding is the angle in the main vibration direction 97 set in step 1 and the angle for correction set in step 9 Are added to the angle direction. Usually, since the angle for correction is minute, the vibration direction of the ultrasonic wave acting on the semiconductor chip 150 at the time of bonding can be regarded as being equal to the main vibration direction 97. As described above, in the present embodiment, the semiconductor chip 15
The semiconductor chip 150 is mounted on the circuit board by applying ultrasonic vibration in an appropriate direction that does not cause the displacement of the bumps 11 without changing the angle at which the semiconductor chip 150 is held and the positional relationship between the holding member 95 and the semiconductor chip 150. 20. Therefore, the semiconductor chip 150 does not cause displacement and the joining strength does not decrease.

In the above embodiment, the semiconductor chip 150 on which the bumps 11 are formed is moved toward the circuit board 20 in the Z direction and pressed, but the present invention is not limited to this. That is, as shown in FIG.
May be formed on the electrode portion 21 of the circuit board 20. For example, as shown in FIG. 15, a bonding stage on which the circuit board 20 is mounted with the bump bonding apparatus 205 fixed during bump bonding. 203 may be moved to the bump bonding apparatus 205. As the driving device for the movement, for example, the voice coil motor 221 as described above is used, and as described above, the voice coil motor 2
The amount of movement may be controlled by the current value supplied to 21. In short, the bump 11 and the electrode unit 21 may be relatively moved during the bump bonding. In FIG. 15, reference numeral 207 indicates a Y-axis robot, and reference numeral 208 indicates an X-axis robot.

In the above-described embodiment, the ultrasonic vibration is applied to the semiconductor chip 150 via the nozzle 93.
The present invention is not limited to this, and the circuit board 20 may be ultrasonically vibrated by the ultrasonic vibration generator 209 as shown in FIG. In short, the bump 11 and the circuit board 20
May be relatively vibrated.

In the above embodiment, the holding member 95
Although the semiconductor chip 150 has the same shape and the same area as the semiconductor chip 150, the semiconductor chip 150 may be formed in a size larger than the semiconductor chip 150. By using such a holding member, even when the holding member and the semiconductor chip 150 have different postures in the circumferential direction 1222, an operation for matching the postures can be omitted.

[0051]

As described above in detail, according to the component joining method of the first aspect and the component joining apparatus of the second aspect of the present invention,
After having a bump bonding device, an ultrasonic vibration generating device, and a control device, after changing the vibration direction of the ultrasonic vibration acting when bonding the electronic component and the circuit forming body to the direction for preventing the displacement of the bump. By performing the above-described bonding, it is possible to prevent the electronic components from being displaced by the action of ultrasonic vibration or to reduce the bonding strength due to a reduction in the contact area of the bumps, and it is always optimal for any bonding object. Bonding can be performed in the ultrasonic vibration direction, and the occurrence of product defects can be reduced as compared with the related art.

The above-mentioned vibration direction can be obtained based on the number, arrangement position, etc. of the bumps. When the above-mentioned vibration direction is obtained based on the arrangement position of the bumps, the direction along the axis of symmetry, which makes the arrangement of the bumps substantially symmetric, is determined. By setting the vibration direction as described above, and setting the vibration direction as a direction in which a bump can be bonded in the region of the electrode of the electrode of the electronic component or the electrode of the circuit forming body, the bump arrangement and the pattern of the electrode unit are changed. The joining can be always performed in the optimum ultrasonic vibration direction even for different joining objects. Therefore, it is possible to prevent the displacement of the electronic component and the decrease in the bonding strength of the bump, and to eliminate the difference in the bonding quality and the defective rate caused by the difference between the bonding target of the electronic component and the circuit board, thereby preventing the occurrence of product failure. It can be reduced compared to the conventional case.

In the second aspect, when the bump bonding apparatus has a configuration in which the ultrasonic vibration generator is mounted on a nozzle having a holding member having the same size as the electronic component mounted on a tip thereof, The bump bonding apparatus,
An attachment changing mechanism may be provided. Therefore, after the ultrasonic vibration generator is rotated by the rotation device provided in the bump bonding apparatus, the nozzle is changed by the attachment changing mechanism with respect to the ultrasonic vibration generator in order to change the posture of the holding member. Can be changed, and the posture of the holding member and the electronic component can be matched. Therefore, the ultrasonic vibration can be reliably transmitted from the holding member to the electronic component, and the electronic component can be reliably joined. Further, since the same holding member can be used even when the arrangement direction of the ultrasonic vibration generator changes, the ultrasonic wave application direction can be changed without increasing the types of the holding members.

Further, by providing the image pickup apparatus, the change of the mounting posture of the nozzle can be executed based on the image pickup information, so that the work time can be shortened and facilitated, and the workability can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an entire component joining apparatus according to an embodiment of the present invention.

FIG. 2 is an enlarged perspective view of a bump bonding apparatus provided in the component bonding apparatus shown in FIG.

FIG. 3 is a block diagram for explaining a control system of a control device provided in the component joining apparatus shown in FIG.

FIG. 4 is a perspective view for explaining a state in which a nozzle is attached to an ultrasonic horn in the bump bonding apparatus.

FIG. 5 is a diagram for explaining a main vibration direction of ultrasonic vibration generated by an ultrasonic vibration generator provided in the bump bonding apparatus.

FIG. 6 is a diagram for explaining a main vibration direction of ultrasonic vibration generated by an ultrasonic vibration generator provided in the bump bonding apparatus.

FIG. 7 is a diagram for explaining a main vibration direction of ultrasonic vibration generated by an ultrasonic vibration generator provided in the bump bonding apparatus.

8 is a flowchart of a component joining operation performed by the component joining apparatus shown in FIG.

FIG. 9 is a view showing bumps formed on a semiconductor chip handled by the component bonding apparatus shown in FIG. 1;

FIG. 10 is a diagram showing a state in which the bumps shown in FIG. 9 are joined to electrode portions of a circuit board.

11 is an enlarged perspective view of a bonding stage provided in the component bonding apparatus shown in FIG.

FIG. 12 is an enlarged view of a piezoelectric element, an ultrasonic horn, a nozzle, and a holding member in the bump bonding apparatus.

FIG. 13 is a diagram showing a displacement between a holding member and a semiconductor chip in the bump bonding apparatus.

14 is a view showing a modification of the structure shown in FIG. 9 and showing a state in which bumps are formed on a circuit board.

FIG. 15 is a view showing a modification of the component bonding apparatus shown in FIG. 1 and showing a structure in which the circuit board side can be moved in the Z direction and further subjected to ultrasonic vibration.

FIG. 16 is a perspective view showing a main part of a conventional component joining apparatus.

FIG. 17 is a perspective view showing an electronic component with bumps.

FIG. 18 is a diagram showing a positional relationship between an electrode portion of a circuit board and a bump.

FIG. 19 is a diagram showing a state in which the bump has contacted a wiring pattern due to deformation of the bump due to ultrasonic vibration.

FIG. 20 is a diagram showing a state where ultrasonic vibration is applied in an inappropriate direction.

[Explanation of symbols]

9 ... ultrasonic vibration generator, 11 ... bump, 13 ... electrode,
Reference numeral 20: circuit board, 21: electrode part, 93: nozzle, 95 ...
Holding member, 97: main vibration direction, 98: mounting change mechanism, 1
01: Component bonding apparatus, 105: Bump bonding apparatus, 110
... Control device, 122 ... Rotating device, 124 ... Imaging device, 1
50: semiconductor chip, 971, 972: symmetry axis, 122
2. Circumferential direction.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Makoto Akita 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F term (reference) 5E313 AA03 AA11 AA21 CD01 CD06 DD21 EE02 EE03 EE11 EE23 EE24 EE33 EE38 5E319 AA03 AB05 AC02 AC03 AC04 CC11 GG15 5F044 LL01 LL04 PP16

Claims (7)

[Claims] An electrode (13) for an electronic component (150);
The electrode part (21) of the circuit forming body (20) is bumped (1).
In the method for joining components via 1), the joining direction is changed after changing the vibration direction (97) of the ultrasonic vibration acting upon the joining in a direction for preventing the displacement of the bumps. A component joining method characterized by the above-mentioned. 2. The vibration direction is obtained based on at least one of a number of the bumps, an arrangement position of the bumps, a material of the bumps, and a height of the bumps. 2. The component joining method according to claim 1, wherein the joining is performed while relatively ultrasonically vibrating the circuit forming body along the vibration direction. 3. When the vibration direction is determined based on the arrangement position of the bump, the vibration direction is determined as a direction along an axis of symmetry (971, 972) that makes the arrangement of the bump substantially symmetric. 2. The component joining method according to 2. 4. The component bonding method according to claim 1, wherein the vibration direction is a direction in which the bumps are bonded by the ultrasonic vibration in a region of the electrode or the electrode portion. 5. An electrode (13) of an electronic component (150),
The electrode part (21) of the circuit forming body (20) is bumped (1).
1) a bump bonding apparatus (105) for bonding via an ultrasonic vibration generating apparatus that relatively ultrasonically vibrates the electronic component and the circuit forming body along a vibration direction during a bonding operation by the bump bonding apparatus ( 9) and determining the vibration direction based on at least one of the number of the bumps, the arrangement position of the bumps, the material of the bumps, and the height of the bumps, and determining the vibration direction along the determined vibration direction. A control device (110) for generating an ultrasonic vibration in the ultrasonic vibration generating device. 6. The above-mentioned bump bonding apparatus has a configuration in which the ultrasonic vibration generator is attached to a nozzle (93) having a holding member (95) having the same size as the electronic component attached to a tip thereof. The bump bonding apparatus further includes a rotating device (122) for rotating the ultrasonic vibration generating device in a circumferential direction (1222) of the nozzle, and the control device controls the rotation by the rotating device. The ultrasonic vibration generator is arranged along the vibration direction to generate ultrasonic vibrations along the vibration direction in the ultrasonic vibration generator, and the ultrasonic vibration generator is rotated by the rotating device. The component joining apparatus according to claim 5, further comprising an attachment changing mechanism (98) for changing the attachment of the nozzle to a posture capable of holding the electronic component. 7. An imaging device (12) for imaging the holding member.
4) and a monitor (124) for visually displaying the imaging information.
The component joining apparatus according to claim 6, further comprising: (3).