阅读说明：本技术 超声波接合头、超声波接合装置及超声波接合方法 (Ultrasonic bonding head, ultrasonic bonding apparatus, and ultrasonic bonding method ) 是由 须永诚寿郎 宫腰敏畅 大友龙矩 于 2019-06-28 设计创作，主要内容包括：本发明提供实现装置的小型化并可进行良好的超声波接合的超声波接合头、超声波接合装置及超声波接合方法。超声波接合头(40)具有：振子单元(50),在长边轴的前端侧形成有被推到应接合的接合预定部分的按压部(52a)；保持部(60),以沿着长边轴振子单元的前端成为自由端的方式,沿着振子单元的长边轴以悬臂梁状保持基端侧；加压轴(80),以振子单元沿着与长边轴大致垂直的垂直轴移动的方式与保持部(62)连结,传递将按压部(52a)压附到接合预定部的力。在保持部(60)具备在处于从保持部保持振子单元的主保持位置沿着长边轴(X)朝向振子单元的自由端的中途的反作用力分散位置上与振子单元抵接的抑制部(90)。(The invention provides an ultrasonic bonding head, an ultrasonic bonding apparatus and an ultrasonic bonding method, which can realize miniaturization of the apparatus and perform good ultrasonic bonding. The ultrasonic bonding head (40) comprises: a vibrator unit (50) having a pressing portion (52a) formed on the distal end side of the long shaft and pushed to a joining portion to be joined; a holding section (60) for holding the proximal end side in a cantilever shape along the long-side axis of the vibrator unit so that the distal end of the vibrator unit becomes a free end along the long-side axis; and a pressing shaft (80) which is connected to the holding portion (62) so that the transducer unit can move along a vertical axis substantially perpendicular to the longitudinal axis, and which transmits a force for pressing the pressing portion (52a) to the portion to be joined. The holding section (60) is provided with a restraining section (90) which abuts the vibrator unit at a reaction force dispersing position located midway from a main holding position where the holding section holds the vibrator unit along the long axis (X) toward the free end of the vibrator unit.)

1. An ultrasonic bonding head is characterized in that,

comprising:

a vibrator unit having a pressing portion formed on a distal end side of the long shaft so as to be pushed to a joining portion to be joined;

a holding portion that holds a base end side along the long axis of the transducer unit in a cantilever shape so that a tip of the transducer unit becomes a free end along the long axis;

a pressing shaft coupled to the holding portion so that the vibrator unit moves along a vertical axis substantially perpendicular to the longitudinal axis, the pressing shaft transmitting a force for pressing the pressing portion to the portion to be joined,

the holding portion includes a suppression portion that abuts against the vibrator unit at a reaction force distribution position that is midway from a main holding position where the holding portion holds the vibrator unit toward a free end of the vibrator unit along the long axis.

2. The ultrasonic bonding head of claim 1,

the suppression portion is attached to the holding portion such that the suppression portion abuts against the vibrator unit at a position of a vibration node closest to a free end of the vibrator unit.

3. The ultrasonic bonding head according to claim 1 or 2,

the position where the suppressing portion abuts against the vibrator unit and the position where the pressing portion abuts against the scheduled joining portion are different along the long axis and are located on opposite sides of the long axis from each other.

4. The ultrasonic bonding head according to claim 1 or 2,

the pressure shaft is coupled to the holding portion such that an axial center of the pressure shaft is substantially parallel to the vertical axis and is positioned between the main holding position and the reaction force distribution position.

5. The ultrasonic bonding head according to claim 1 or 2,

the vibrator unit is provided with a vibration source in such a manner that the pressing portion ultrasonically vibrates in a direction parallel to the longitudinal axis.

6. The ultrasonic bonding head according to claim 1 or 2,

the surface of the suppression portion in contact with the vibrator unit is subjected to low-friction treatment for improving relative movement along the long-side axis.

7. The ultrasonic bonding head according to claim 1 or 2,

the holding portion further includes an auxiliary holding portion that holds a cover covering the vibration source of the vibrator unit at a sub-holding position different from the main holding position along the long axis.

8. An ultrasonic bonding head is characterized in that,

comprising:

a vibrator unit having a pressing portion formed on a distal end side of the long shaft so as to be pushed to a joining portion to be joined;

a holding portion that holds a base end side along the long axis of the transducer unit in a cantilever shape so that a tip of the transducer unit becomes a free end along the long axis;

a pressing shaft coupled to the holding portion so that the vibrator unit moves along a vertical axis substantially perpendicular to the longitudinal axis, the pressing shaft transmitting a force for pressing the pressing portion to the portion to be joined,

when a position where the holding portion mainly holds the vibrator unit is set as a main holding position and a position where the suppressing portion provided in the holding portion abuts against the vibrator unit is set as a reaction force dispersing position,

the main holding position and the reaction force dispersing position are arranged in this order from the tip end of the transducer unit toward the base end along the longitudinal axis of the transducer unit.

9. An ultrasonic bonding apparatus, characterized in that,

the ultrasonic bonding head according to any one of claims 1 to 8.

10. An ultrasonic bonding method is characterized in that,

the ultrasonic bonding of the bonding predetermined portion is carried out by using the ultrasonic bonding head according to any one of claims 1 to 8.

11. An ultrasonic bonding method is characterized in that,

comprising:

a step of holding a base end side along a long-side axis of a vibrator unit in a cantilever shape so that a tip of the vibrator unit becomes a free end along the long-side axis;

a step of pushing a pressing portion provided at a distal end of the transducer unit to a portion to be bonded, and causing the pressing portion to perform ultrasonic vibration in the longitudinal axis direction,

when a position where the holding portion mainly holds the vibrator unit is set as a main holding position and a position where the suppressing portion provided in the holding portion abuts against the vibrator unit is set as a reaction force dispersing position,

the vibrator unit has two or more vibration nodes along the long axis,

the primary holding position and the reaction force dispersion position are located at mutually different positions of the vibration node.

Technical Field

The invention relates to an ultrasonic bonding head, an ultrasonic bonding apparatus and an ultrasonic bonding method.

Background

For example, an ultrasonic bonding apparatus shown in patent document 1 is known. In this ultrasonic bonding apparatus, both sides of the ultrasonic horn in the longitudinal direction are held, and a pressing portion provided at the center portion of the horn is pressed against a bonding scheduled portion to perform ultrasonic bonding.

In the conventional ultrasonic bonding apparatus, in order to increase the ultrasonic vibration of the pressing portion, the length of the ultrasonic horn needs to be increased, which causes a problem that the entire apparatus becomes large. Further, since the holding portions of the ultrasonic horn are located on both sides, there is a possibility that the holding portions may obstruct the ultrasonic vibration.

In addition, ultrasonic bonding of wiring of a glass substrate serving as a display screen substrate and a Flexible Printed Circuit (FPC) or the like has been studied, but in a conventional ultrasonic bonding device, the device is too large to hold both sides of an ultrasonic horn, and thus is not practical.

Disclosure of Invention

The present invention has been made in view of such circumstances, and an object thereof is to provide an ultrasonic bonding head, an ultrasonic bonding apparatus, and an ultrasonic bonding method that can achieve a reduction in size of the apparatus and perform satisfactory ultrasonic bonding.

In order to achieve the above object, an ultrasonic bonding head according to a first aspect of the present invention includes:

a vibrator unit having a pressing portion formed on a distal end side of the long shaft so as to be pushed to a joining portion to be joined;

a holding portion that holds a base end side in a cantilever shape along the long axis of the transducer unit such that a tip of the transducer unit becomes a free end along the long axis;

a pressing shaft coupled to the holding portion so that the vibrator unit moves along a vertical axis substantially perpendicular to the longitudinal axis, the pressing shaft transmitting a force for pressing the pressing portion to the portion to be joined,

the holding portion includes a restraining portion that abuts against the vibrator unit at a reaction force dispersing position that is midway from a main holding position where the holding portion holds the vibrator unit toward a free end of the vibrator unit along the long axis.

In the ultrasonic bonding head according to the present invention, since the holding portion holds the proximal end side along the longitudinal axis in a cantilever shape with respect to the transducer unit including the ultrasonic horn (horn), the ultrasonic vibration in the pressing portion can be increased, and the device can be downsized compared to the case where the transducer unit is held from both sides.

In the ultrasonic bonding head according to the present invention, the holding portion includes a suppression portion that comes into contact with the transducer unit at a position where the reaction force is dispersed midway along the longitudinal axis toward the free end of the transducer unit. Therefore, a part of the reaction force of the pressing force with which the pressing portion provided at the free end of the vibrator unit is pressed to the joining scheduled portion can be received by the suppression portion, and the bending deformation of the vibrator unit is suppressed. As a result, the pressing force of the pressing shaft can be increased, the pressure of the pressing portion against the portion to be joined can be increased, and good ultrasonic joining can be performed. Further, the width of the joining portion can be increased, and ultrasonic joining of the flat plate-like members can be facilitated.

Preferably, the suppression portion is attached to the holding portion such that the suppression portion abuts the transducer unit at a position of a vibration node closest to the free end of the transducer unit. With this configuration, the reaction force of the pressing force received by the suppression section is increased, and the bending deformation of the transducer unit is effectively suppressed. As a result, the pressing force of the pressing shaft can be increased, the pressure of the pressing portion against the portion to be joined is increased, and the reliability of the ultrasonic joining is improved. Further, the width of the joining portion can be increased, and ultrasonic joining of the flat plate-like members is facilitated.

Further, the suppression unit is brought into contact with the transducer unit at the position of the vibration node (the position where the amplitude of vibration becomes minimum), and thus the suppression unit rarely blocks the ultrasonic vibration in the transducer unit.

Preferably, the position where the suppressing portion abuts against the transducer unit and the position where the pressing portion abuts against the portion to be joined are different along the longitudinal axis and are located on opposite sides of the longitudinal axis. The suppression section is in contact with the transducer unit within a range that requires a minimum limit so as to suppress bending of the transducer unit upon receiving a reaction force from the pressing section, thereby further reducing the possibility that the suppression section will block ultrasonic vibration in the transducer unit.

Preferably, the holding portion holds the entire circumference of the transducer unit at the main holding position, but the suppressing portion preferably contacts only a part of the entire circumference of the transducer unit with a small area.

Preferably, the pressing shaft is coupled to the holding portion such that an axial center of the pressing shaft is substantially parallel to the vertical axis and is positioned between the main holding position and the reaction force dispersing position. With this configuration, the pressing force from the pressing shaft can be efficiently transmitted to the pressing portion, the pressing force applied from the pressing portion to the portion to be joined can be increased, and the reliability of ultrasonic joining can be improved.

Preferably, the vibrator unit has a vibration source attached thereto such that the pressing portion ultrasonically vibrates in a direction parallel to the longitudinal axis. By the pressing portion ultrasonically vibrating in the direction parallel to the longitudinal axis, ultrasonic bonding of fine metal patterns to each other along the direction parallel to the longitudinal axis is facilitated.

Preferably, the surface of the suppression portion that abuts the transducer unit is subjected to a low-friction treatment that enhances relative movement along the longitudinal axis. With this configuration, the suppression section further reduces the possibility of the suppression section blocking the ultrasonic vibration in the transducer unit.

The holding portion may further include an auxiliary holding portion for holding a cover covering the vibration source of the vibrator unit at an auxiliary holding position different from the main holding position along the long axis.

An ultrasonic bonding head according to a second aspect of the present invention includes:

a vibrator unit having a pressing portion formed on a distal end side of the long shaft so as to be pushed to a joining portion to be joined;

a holding portion that holds a base end side in a cantilever shape along the long axis of the transducer unit so that a tip of the transducer unit becomes a free end along the long axis; a pressing shaft coupled to the holding portion so that the vibrator unit moves along a vertical axis substantially perpendicular to the longitudinal axis, the pressing shaft transmitting a force for pressing the pressing portion to the portion to be joined,

the position where the holding part mainly holds the vibrator unit is set as a main holding position,

when the position where the suppressing portion provided in the holding portion abuts against the transducer unit is set as the reaction force dispersing position,

the main holding position and the reaction force dispersing position are arranged in this order from the tip end of the transducer unit toward the base end along the longitudinal axis of the transducer unit.

In the ultrasonic bonding head according to the second aspect of the present invention, since the holding portion holds the proximal end side of the transducer unit including the ultrasonic horn in a cantilever shape along the long axis, the ultrasonic vibration in the pressing portion can be increased, and the device can be made smaller than a case where the transducer units are held from both sides.

In the ultrasonic bonding head according to the present invention, the holding portion mainly holds the transducer unit at the main holding position, and the suppressing portion that comes into contact with the transducer unit at the holding portion at the reaction force dispersing position. Therefore, a part of the reaction force of the pressing force, which is provided at the free end of the vibrator unit and is pressed against the joining scheduled portion, can be received by the suppression portion, suppressing the bending deformation of the vibrator unit. As a result, the pressing force of the pressing shaft can be increased, and the pressure of the pressing portion against the portion to be bonded can be increased, thereby enabling favorable ultrasonic bonding. Further, the width of the joining portion can be increased, and ultrasonic joining of the flat plate-like members can be facilitated.

An ultrasonic bonding apparatus according to the present invention includes any one of the ultrasonic heads described above.

The ultrasonic bonding apparatus according to the present invention does not necessarily need to have a stage, but may have a general stage or may further have a special stage provided with a first planar member and a second planar member to be bonded.

The platform may also have:

a lower side surface provided with the first planar member;

a high-level side surface located at a high position with respect to the low-level side surface by a prescribed step height, the second planar member being provided;

a step wall surface located at a boundary of the low-level side surface and the high-level side surface.

In order to perform ultrasonic joining of the first planar member and the second planar member, first, the first planar member is provided on the lower-level side surface in such a manner that an end portion of the first planar member is positioned on the step wall surface. Next, the second planar member is provided on the high-level side surface in such a manner as to form a laminated portion in which at least a part of the second planar member is laminated over the first planar member. After that, the pressing portion of the ultrasonic horn is pushed up to the laminated portion at a position corresponding to the step wall surface, and the ultrasonic bonding is completed.

When the surface of the stage has a step wall surface, the step wall surface facilitates positioning of the first planar member and the second planar member, and ultrasonic bonding of the wiring patterns can be performed. Therefore, even when the pitch between the wirings is narrow to about several tens μm or less, for example, short-circuit failure or the like does not occur, and the planar members are easily electrically connected to each other.

Further, recently, as a display screen of a smartphone or the like, a display screen as large as the outer size of the device is required, and therefore, the bonding length between the wiring patterns also has to be shortened, which causes a problem in connection reliability. According to the device of the present invention, solid-state bonding of metals to each other can be performed by ultrasonic bonding, and the reliability of connection is also improved.

In addition, in the case where the surface of the stage has a step wall surface, the wiring patterns can be reliably ultrasonically bonded to each other even if the width of the laminated portion of the first planar member and the second planar member is as large as, for example, 60mm or more.

The platform may also have:

a first fixing unit that detachably fixes the first planar member to the lower-level side surface such that an end of the first planar member is positioned in contact with the step wall surface;

and a second fixing unit that detachably fixes the second planar member to the high-position side surface such that at least a part of the second planar member is stacked on the first planar member.

The first fixing means is not particularly limited, but for example, a plurality of first suction holes formed in the lower surface of the stage. The first flat member can be detachably fixed to the lower-position side surface by introducing negative pressure into the plurality of first suction holes. Similarly, the second fixing means is not particularly limited, and for example, a plurality of outer second suction holes formed in the high-level side surface of the stage are exemplified. The second flat member can be detachably fixed to the high-position side surface by introducing negative pressure into the plurality of second suction holes.

The step height may be equal to or less than the thickness of the first planar member. With this configuration, even if there is a manufacturing error of the stage, the upper surface of the first planar member does not become lower than the high-position side surface, and the upper surface of the first planar member is flush with the high-position side surface or slightly protrudes upward. Therefore, in the case where the second planar member is provided on the high-order side surface, the first planar member and the second planar member are surely in contact at their laminated portions (repeated portions). Therefore, ultrasonic bonding can be reliably performed, and the reliability of the connection portion is further improved.

An ultrasonic bonding method according to a first aspect of the present invention is characterized in that ultrasonic bonding is performed on a portion to be bonded by using any one of the ultrasonic bonding heads described above.

An ultrasonic bonding method according to a second aspect of the present invention includes:

holding a base end side in a cantilever shape along the long axis of the transducer unit so as to be a free end along a tip end of the long axis transducer unit;

a step of pushing a pressing portion provided at a distal end of the transducer unit to a portion to be bonded, and causing the pressing portion to perform ultrasonic vibration in the longitudinal axis direction,

the position where the holding part mainly holds the vibrator unit is set as a main holding position,

when the position where the suppressing portion provided in the holding portion abuts against the transducer unit is set as the reaction force dispersing position,

two or more vibration nodes are present in the vibrator unit along the long side axis,

the primary holding position and the reaction force dispersion position are located at mutually different positions of the vibration node.

In the ultrasonic joining method according to the first and second aspects of the present invention, since the holding portion holds the proximal end side of the transducer unit including the ultrasonic horn in a cantilever shape along the longitudinal axis, the ultrasonic vibration in the pressing portion can be increased, and the device can be downsized compared to the case where the transducer unit is held from both sides.

In the ultrasonic bonding method of the present invention, the holding portion includes a suppression portion that comes into contact with the transducer unit at the reaction force dispersing position. Therefore, a part of the reaction force of the pressing force, which is provided at the free end of the vibrator unit and is pressed against the joining scheduled portion, can be received by the suppression portion, and the bending deformation of the vibrator unit can be suppressed. As a result, the pressing force of the pressing shaft can be increased, the pressure of the pressing portion against the portion to be welded can be increased, and good ultrasonic welding can be performed. Further, the width of the joining portion can be increased, and ultrasonic joining of the flat plate-like members can be facilitated.

In particular, by positioning the main holding position and the reaction force dispersing position at different positions of the vibration nodes from each other, the fear that the ultrasonic vibration in the transducer unit is blocked by the holding of the holding portion at the main holding position is reduced, and the fear that the suppressing portion blocks the ultrasonic vibration in the transducer unit is reduced.

Drawings

Fig. 1A is a schematic perspective view of an ultrasonic bonding head according to an embodiment of the present invention.

Fig. 1B is a schematic diagram showing a relationship between a front view of the ultrasonic bonding head shown in fig. 1A and a vibration node.

Fig. 1C is a rear view of the ultrasonic bonding head shown in fig. 1B.

Fig. 1D is a plan view of the ultrasonic bonding head shown in fig. 1B.

Fig. 1E is a bottom view of the ultrasonic bonding head shown in fig. 1B.

Fig. 1F is a left side view of the ultrasonic bonding head shown in fig. 1B.

Fig. 1G is a right side view of the ultrasonic bonding head shown in fig. 1B.

Fig. 1H is a front view of the ultrasonic transducer unit shown in fig. 1A.

Fig. 1I is a rear view of the ultrasonic transducer unit shown in fig. 1H.

Fig. 1J is a plan view of the ultrasonic transducer unit shown in fig. 1H.

Fig. 1K is a bottom view of the ultrasonic transducer unit shown in fig. 1H.

Fig. 1L is a left side view of the ultrasonic transducer unit shown in fig. 1H.

Fig. 1M is a right side view of the ultrasonic transducer unit shown in fig. 1H.

Fig. 2A is an overall configuration diagram of an ultrasonic bonding apparatus including the ultrasonic bonding head shown in fig. 1A.

Fig. 2B is a schematic view showing one step of an ultrasonic bonding method using the ultrasonic bonding apparatus shown in fig. 2A.

Fig. 3 is a schematic diagram showing the subsequent steps of fig. 2.

Fig. 4 is a schematic diagram showing a subsequent stage of fig. 3.

Fig. 5A is a schematic view showing a subsequent stage of fig. 4.

Fig. 5B is a schematic diagram showing the subsequent steps of fig. 5A.

Fig. 6 is a schematic view showing a modification of the ultrasonic bonding head shown in fig. 1B.

Description of the symbols

2 … ultrasonic bonding device

4 … electronic control base plate (first plane component)

4a … Wiring Pattern

6 … Flexible Board (second plane component)

6a … Wiring Pattern

8 … substrate assembly

10 … platform

10a … low side surface

10a1 … engaged position

10a2 … standby position

10b … high side surface

10c … step wall

11 … Standby adsorption hole

12 … first adsorption hole

14 … second adsorption hole

20 … delivery head

30 … camera

40 … ultrasonic bonding head

50 … ultrasonic transducer unit

52 … ultrasonic horn

52a … pressing part

54 … intensifier

56 … vibration source cover

58 … Cable

60 … holding part

62 … upper holding part

63 … pressure transfer block

64 … lower holding part

70 … auxiliary holding part

72 … Upper holding part

73 … mounting flange

74 … lower holding part

80 … pressure shaft

82 … fixed disk

90 … restraining pin (restraining part)

92 ….

Detailed Description

The present invention will be described below based on embodiments shown in the drawings.

First embodiment

The ultrasonic bonding head 40 will be described with reference to fig. 1A to 1M. The ultrasonic bonding head 40 of the present embodiment includes an ultrasonic transducer unit 50, a holding portion 60 for holding the ultrasonic transducer unit 50, and a pressurizing shaft 80 coupled to the holding portion 60 and moving the holding portion 60 and the ultrasonic transducer unit 50 in the Z-axis direction.

As shown in fig. 1H to 1M, the transducer unit 50 includes an ultrasonic horn 52, a booster (booster)54, and a vibration source cover 56, which are connected in this order along the X axis. The vibration source not shown is housed inside the vibration source cover 56. The vibration source is not particularly limited, but for example, a piezoelectric element is exemplified.

The vibration source is positioned and fixed inside the vibration source cover 56, but is not directly fixed to an auxiliary holding portion 70 (see fig. 1A) described below. The vibration source vibrates by electric power, and the electric cable 58 projects from the rear end of the vibration cover 56 in the X axis direction because electric power is supplied to the vibration source.

As shown in fig. 1A, a booster 54 is fixedly coupled to the front side (the distal end direction of the ultrasonic horn 52) of the vibration source housed in the vibration source cover 56 in the X axis direction. As the booster 54, a general booster for an ultrasonic bonding apparatus is used, and extends in the X-axis direction. The vibration source and the booster 54 are coupled by, for example, screw coupling.

An ultrasonic horn 52 is fixedly connected to the distal end of the booster 54 in the X-axis direction. The booster 54 and the ultrasonic horn 52 are coupled by the same means as the coupling of the vibration source and the booster 54. In the present embodiment, the intensifier 54 has a cylindrical shaft shape with an outer diameter that varies along the axial direction.

The ultrasonic horn 52 has a special rectangular prism shape elongated in the axial direction, and a pressing portion 52a protruding in the Z-axis direction and linearly extending in the Y-axis direction is formed at the tip in the X-axis direction and at the lower end in the Z-axis direction. The width of the pressing portion 52a in the Y-axis direction is determined by the width of the portion to be welded to be ultrasonically welded in the Y-axis direction, and the like. The width X2 in the X axis direction of the pressing portion 52a shown in fig. 5A is determined by the width in the X axis direction of the portion to be joined and the like, as described below, and is not particularly limited, but is 0.2 to 2.0mm in the present embodiment.

As shown in fig. 1B, the vibration source housed in the vibration source cover 56 is configured to vibrate in the X-axis direction, and the vibration is amplified by the booster 54, transmitted to the ultrasonic horn 52, and increased in amplitude at the pressing portion 52 a. The transducer unit 50 including the ultrasonic horn 52, the booster 54, and the vibration source has a central axis (longitudinal axis) X0 thereof, vibrates along the longitudinal axis X0 (parallel to the X axis), and has a portion where the amplitude V of the vibration (standing wave) is large (antinode of the vibration) and a portion where the amplitude V is minimum (0) (vibration node). In the present embodiment, as shown in the drawing, the vibration nodes are at least two along the long axis X0.

The transducer unit 50 is held at the main holding position P3 by the holding portion 60 so that the distal end (the pressing portion 52a side) along the longitudinal axis X0 becomes a free end (one end that can freely move). The main holding position P3 is located at a position halfway through the booster 54 in the present embodiment, and is located closer to the vibration node on the vibration source side than the distal end of the ultrasonic horn 52.

The auxiliary holder 70 is coupled to the rear end by a bolt or the like along the longitudinal axis X0 of the holder 60, and the auxiliary holder 70 holds the vibration source cover 56 at the auxiliary holding position P4. The secondary holding position P4 is preferably at the position of the vibration node located closest to the vibration source, but need not necessarily be at the position of the vibration node. This is because the auxiliary holding portion 70 holds the vibration cover 56 at the auxiliary holding position P4, but does not hold the vibration source itself.

In the present embodiment, the lower portion of the distal end of the ultrasonic horn 52 serves as a pressing portion 52 a. The pressing portion 52a is attached to the transducer unit 50 with a vibration source so as to be located at a leading end position P1 of an antinode of vibration in which the amplitude V of vibration by ultrasonic vibration is increased to the maximum in a direction parallel to X0.

In the present embodiment, the holding unit 60 includes a restraining pin (restraining unit) 90 that abuts (only contacts and is not fixed to) the transducer unit 50 at a reaction force distribution position (fulcrum) P2 that is midway along the long axis X0 toward the free end (tip position P1/action point) of the transducer unit 50 from a main holding position (load point of applied pressure) P3 where the booster 54 that holds the transducer unit 50 by the holding unit 60 is located.

The axis Z0 of the pressure shaft 80 is substantially parallel to the vertical axis Z, and the pressure shaft 80 is connected to the holding section 60 via the fixed disk 82 so as to be positioned between the main holding position P3 and the reaction force distribution position P2. The pressing shaft 80 is coupled to the holding portion 60 so that the transducer unit 50 moves along the Z-axis, which is a vertical axis substantially perpendicular to the longitudinal axis X0, and transmits a force for pressing the pressing portion 52a to the portion to be engaged (not shown in fig. 1B).

In the present embodiment, the mounting of the pin 90 to the holding portion 60 is suppressed so that the contact portion 92 of the pin 90 contacts the ultrasonic horn 52 of the transducer unit 50 at the reaction force distribution position P2 of the vibration node closest to the free end of the transducer unit 50. The position P2 at which the restraining pin 90 abuts against the vibrator unit 50 and the position P1 at which the pressing portion 52a abuts against the portion to be joined are different along the longitudinal axis X0 and are located on opposite sides of the longitudinal axis X0 along the Z axis.

In the present embodiment, the surface of the contact portion 92 of the suppression pin 90 that contacts the ultrasonic horn 52 of the transducer unit is subjected to a low friction treatment that enhances the relative movement of the horn 52 and the contact portion 92 along the longitudinal axis X0. The low friction treatment is not particularly limited, but it is conceivable that the contact portion 92 is formed of a low friction member such as a fluororesin. Further, a low friction member such as paraffin or wax may be applied or formed on the surface of the contact portion 92, or a method of attaching a fluorine resin tape may be used.

The size of the contact portion 92 of the restraining pin 90 is not particularly limited, but is preferably a size sufficient to receive the reaction force from the front end position P1 applied to the reaction force distribution position P2, and is preferably as small as possible to reduce the frictional force. The width of the contact portion 92 in the Y-axis direction is equal to or smaller than the width of the ultrasonic horn 52 in the Y-axis direction, and is preferably smaller from the viewpoint of not inhibiting the vibration of the horn. The width of the contact portion 92 in the X-axis direction is equal to or smaller than the length of the ultrasonic horn 52 in the X-axis direction, and is preferably smaller from the viewpoint of not inhibiting the vibration of the horn. The outer diameter of the restraining pin 90 may be smaller than the outer diameter of the abutment portion 92, but is preferably so large as to receive the reaction force.

As shown in fig. 1A, the holding portion 60 includes an upper holding portion 62 and a lower holding portion 63, which are coupled to each other by a bolt or the like at a main holding position P3 shown in fig. 1B, thereby holding the booster 54 of the vibrator unit 50 around the entire circumference thereof. Further, the upper holding portion 62 and the lower holding portion 64 of the holding portion 60 are in contact with the booster 54 with a predetermined width in the X-axis direction, but a cover is formed on the outer periphery of the booster 54, and the outer periphery of the cover is held by the holding portion 60, so that the holding portion 60 holds the booster 54 substantially at the main holding position P3.

A pressure transmission block 63 extending along the X axis in the direction of the distal end of the ultrasonic horn 52 and covering the upper Z axis of the ultrasonic horn 52 is integrally formed in the upper holding portion 62. The pressure transmission block 63 is not in contact with the ultrasonic horn 52 except for the suppression pin 90. The fixed plate 82 is fixed to the upper surface of the pressure transmission block 63, and the pressurizing shaft 80 is fixed to the holding portion 60 via the fixed plate 82.

The mounting flange 73 formed integrally with the upper holding portion 72 of the auxiliary holding portion 70 is fixed to the upper holding portion 62 of the holding portion 60 by bolts or the like, and the upper holding portion 72 and the lower holding portion 74 are combined to hold the outer periphery of the vibration source cover 56 at the sub-holding position P4 shown in fig. 1B.

In the ultrasonic bonding head 40 according to the present embodiment, since the holding portion 60 holds the proximal end side of the transducer unit 50 including the ultrasonic horn 52 in a cantilever shape along the longitudinal axis X0, the ultrasonic vibration in the pressing portion 52a can be increased, and the device including the head 40 can be downsized compared to the case of holding the transducer unit 50 from both sides.

In the ultrasonic bonding head 40 of the present embodiment, the holding portion 60 includes the suppression pin 90 that abuts against the transducer unit 50 at the reaction force dispersion position P2 located midway along the longitudinal axis X0 toward the free end of the transducer unit 50. Therefore, the bending deformation of the vibrator unit 50 can be suppressed by suppressing the pin 90 from receiving a part of the reaction force of the pressing force with which the pressing portion 52a provided at the free end of the vibrator unit 50 is press-attached to the joining scheduled portion. As a result, the pressing force of the pressing shaft 80 can be increased, the pressure on the portion to be joined in the pressing portion 52a can be increased, and good ultrasonic joining can be performed. Further, the width of the joining portion in the Y-axis direction can be increased, and ultrasonic joining of the flat plate-like members can be facilitated.

Further, the mounting of the suppression pin 90 to the holding portion 60 is suppressed so that the suppression pin 90 abuts on the transducer unit 50 at a position P2 of the vibration node closest to the free end of the transducer unit 50. With this configuration, the reaction force of the pressing force received by the suppression pin 90 increases, and the bending deformation of the transducer unit 50 can be effectively suppressed. As a result, the pressing force of the pressing shaft 80 can be increased, the pressing force of the pressing portion 52a against the portion to be joined can be increased, and the reliability of ultrasonic joining can be improved. Further, the width of the joining portion in the Y-axis direction can be increased, and ultrasonic joining of the flat plate-like members can be facilitated.

Further, at the position P2 of the vibration node (position where the amplitude of vibration is smallest), the suppression pin 90 is in contact with the transducer unit 50, and thus the suppression pin 90 rarely interferes with the ultrasonic vibration in the transducer unit 50.

Further, a position P2 at which the suppression pin 90 abuts against the transducer unit 50 and a position P1 at which the pressing portion 52a abuts against the portion to be joined are different along the longitudinal axis X0 and are located on opposite sides of the longitudinal axis X0 along the Z axis. The suppression pin 90 contacts the transducer unit 50 within a range that requires a minimum amount so as to receive the reaction force from the pressing portion 52a and suppress the bending of the transducer unit 50, thereby further reducing the possibility that the contact portion 92 of the suppression pin 90 blocks the ultrasonic vibration in the transducer unit 50.

The axial center Z0 of the pressure shaft 80 is coupled to the holding portion 60 so that the pressure shaft 80 is substantially parallel to the Z axis and is positioned between the main holding position P3 and the reaction force distribution position P2. With this configuration, the pressing force from the pressing shaft 80 is efficiently transmitted to the pressing portion 52a, the pressing force applied from the pressing portion 52a to the portion to be joined can be increased, and the reliability of ultrasonic joining can be improved.

The transducer unit 50 is attached with a vibration source to the transducer unit 50 such that the pressing portion 52a ultrasonically vibrates in a direction parallel to the longitudinal axis X0. By the pressing portion 52a ultrasonically vibrating in the direction parallel to the longitudinal axis X0, ultrasonic bonding of fine metal patterns to each other is facilitated in the direction parallel to the longitudinal axis X0.

The ultrasonic bonding head 40 according to the present embodiment does not necessarily need a stage, but may have a general stage or may further have a special stage on which a first planar member and a second planar member to be bonded are provided, as in the third embodiment described below.

The ultrasonic bonding method according to the present embodiment ultrasonically bonds the portion to be bonded using the ultrasonic bonding head 40 described above. Specifically, the ultrasonic bonding method of the present embodiment includes a step of holding the proximal end side in a cantilever shape along the longitudinal axis X0 of the transducer unit 50 such that the distal end of the transducer unit 50 becomes a free end along the longitudinal axis X0. Next, the pressing portion 52a provided at the distal end of the transducer unit 50 is pushed to the portion to be bonded, and the pressing portion 52a is ultrasonically vibrated in the longitudinal axis X0 direction.

When the position at which the holding unit 60 mainly holds the transducer unit 50 is set as the main holding position P3 and the position at which the suppression pin 90 provided in the holding unit 60 contacts the transducer unit 50 is set as the reaction force dispersion position P2, two or more vibration nodes exist in the transducer unit 50 along the long-side axis X0, and the main holding position P3 and the reaction force dispersion position P2 are positioned at different vibration nodes from each other.

In the ultrasonic bonding method according to the present embodiment, since the holding portion 60 holds the proximal end side of the transducer unit 50 including the ultrasonic horn 52 in a cantilever shape along the longitudinal axis X0, the ultrasonic vibration in the pressing portion 52a can be increased, and the device can be downsized compared with the case of holding the transducer unit 50 from both sides か.

In addition, the main holding position P3 and the reaction force dispersing position P2 are positioned at mutually different vibration node positions, whereby the fear of blocking the ultrasonic vibration in the transducer unit 50 due to the holding of the holding portion 60 at the main holding position P3 is reduced, and the fear of blocking the ultrasonic vibration in the transducer unit 50 by the pin 90 is suppressed to be reduced.

Second embodiment

The ultrasonic bonding head according to the second embodiment is the same as the ultrasonic bonding head 40 according to the first embodiment except that the main holding position P3 and the reaction force dispersion position P2 shown in fig. 1B are opposite to each other along the X axis as shown in fig. 6. That is, the main holding position P3 and the reaction force dispersion position P2 are arranged in this order from the distal end of the transducer unit 50 toward the base end along the longitudinal axis X0 of the transducer unit 50.

In the main holding position P3, the holding portion 60 holds the transducer unit 50, and in the reaction force dispersing position P2, the pin 90 is suppressed from coming into contact with a part of the outer periphery of the transducer unit 50. The position where the suppression pin 90 abuts may be the ultrasonic horn 52 or the booster 54. The holding portion 60 may hold the ultrasonic horn 52 or the booster 54.

In the ultrasonic bonding head 50 according to the second embodiment, since the holding portion 60 holds the proximal end side of the transducer unit 50 including the ultrasonic horn 52 in a cantilever shape along the longitudinal axis X0, the ultrasonic vibration in the pressing portion 52a can be increased, and the device can be made smaller than the case of holding the transducer unit 50 from both sides.

Third embodiment

In the third embodiment, a method of manufacturing the substrate bonded body 8 shown in fig. 5B by performing the ultrasonic bonding method shown in fig. 2B to 5B using the ultrasonic bonding apparatus 2 shown in fig. 2A having the acoustic wave bonding head 40 according to one embodiment of the present invention shown in fig. 1A to 1G incorporated with the transducer unit 50 shown in fig. 1H to 1M will be described.

As shown in fig. 5B, the substrate assembly 8 includes the electronic control substrate 4 as a first planar member and the flexible substrate 6 as a second planar member. The electronic control board 4 may be a liquid crystal display panel, an organic EL display panel, or another display panel, and may include a glass substrate, for example.

The flexible substrate 6 is a substrate for supplying some signals and electric power to the electronic control substrate 4, and the wiring pattern 4a of the electronic control substrate 4 and the wiring pattern 6a of the flexible substrate 6 are electrically connected pattern by pattern.

In the substrate assembly 8 shown in fig. 5B, after the wiring pattern 4a and the wiring pattern 6a are ultrasonically bonded, the flexible substrate 6 is bent from the end portion of the electronic control substrate 4 on the wiring pattern 4a side toward the back side, and is housed in, for example, the inside of the housing of the smartphone. With this configuration, the entire surface close to the outer dimension of the housing can be used as the display screen of the electronic control board 4.

From such a viewpoint, it is required that the overlap width X1 (see fig. 5A) of the wiring patterns 4a and 6a in the X-axis direction be as small as possible, for example, 0.5mm or less, preferably 0.2mm or less. In addition, the wiring pitch in the Y-axis direction of the wiring patterns 4a and 6a is, for example, several tens μm or less, and preferably as small as about 20 μm or less, together with the high degree of miniaturization of the screen display. In the figure, the thickness of the substrate 6 is drawn to be approximately the same as that of the substrate 4, but in reality, the thickness of the substrate 6 is smaller than that of the substrate 4, but may be the same or the opposite.

In the present embodiment, the ultrasonic bonding apparatus 2 shown in fig. 2A is used in order to electrically connect the wiring pattern 4a of the electronic control substrate 4 and the wiring pattern 6a of the flexible substrate 6 for each pattern.

As shown in fig. 2A, the ultrasonic bonding apparatus 2 of the present embodiment includes a stage 10 on which an electronic control board 4 and a flexible board 6 to be bonded are provided, and an ultrasonic bonding head 40 including an ultrasonic transducer unit 50 having a pressing portion 52A to be pushed to a laminated portion of the electronic control board 4 and the flexible board 6. The ultrasonic bonding head 40 is the same head 40 as the first embodiment, but another ultrasonic bonding head may be used.

The transfer head 20 is disposed above the stage 10 in the Z-axis direction so as to be movable relative to the stage 10 in the X-axis, Y-axis, and Z-axis directions. Further, at the upper portion of the stage 10 in the Z-axis direction, the camera 30 is disposed so as to be movable relative to the stage 10 at least in the X-axis and Y-axis directions so that the position in the Z-axis direction is offset from the transfer head 20. Similarly to the transfer head 20, the camera 30 may be disposed to be movable in the Z-axis direction relative to the stage 10.

The ultrasonic bonding head 40 is disposed so as to be movable in the X-axis, Y-axis, and Z-axis directions relative to the stage 10 at a position not to collide with the transfer head 20 and the camera 30. The relative movement is free, and means that one may move with respect to the other, that the other may move with respect to the one, or that the one and the other may move with each other, and that the relative positions of the one and the other may change.

The relative movement mechanisms of the stage 10, the ultrasonic bonding head 40, the suction head 20, and the camera 30 are controlled by a control unit not shown. The control unit may also serve as a control device of the apparatus 2, and may perform image processing of an image obtained by the camera 30 and negative pressure control of the suction holes 11, 12, and 14 described below. The control unit may be a dedicated control circuit or may be constituted by a general-purpose computer having a control program.

In the drawing, the X axis, the Y axis, and the Z axis are substantially perpendicular to each other, the Z axis coincides with the height direction of the device 2, the X axis coincides with the longitudinal direction of the electronic control board 4 or the flexible board 6, and the Y axis coincides with the width direction of the electronic control board 4 or the flexible board 6. The X axis and the Y axis are substantially parallel to the display surface of the electronic control board 4.

At least a low-side surface 10a on which the electronic control board 4 is provided, a high-side surface 10b located at a high position with respect to the low-side surface 10a by a predetermined step height Z1, and a step wall surface 10c located at a boundary between the low-side surface 10a and the high-side surface 10b are formed on the Z-axis upper surface of the stage 10. The low-side surface 10a and the high-side surface 10b are respectively substantially parallel to the X-Y axis plane, and the step wall surface 10c is substantially parallel to the Z-Y axis plane.

A bonding position 10a1 where the electronic control substrate 4 is disposed, and a standby position 10a2 separated from the bonding position 10a1 in the X-axis direction (or the Y-axis direction) and preset with the flexible substrate 6 are formed on the lower side surface 10 a. The plurality of first suction holes 12 formed in the interior of the platform 10 are opened at the lower side surface 10a at the engagement position 10a 1. The standby suction holes 11 formed in the stage 10 are opened in the lower side surface 10a located at the standby position 10a 2.

The electronic control board 4 placed at the bonding position 10a1 can be detachably attached to the lower surface 10a at the bonding position 10a1 by applying a negative pressure to the first suction holes 12. At the bonding position 10a1, the electronic control board 4 is arranged such that the portion to be connected of the wiring pattern 4a formed on the board 4 is directed upward in the Z-axis direction, and the end portion of the board 4 on the side of the portion to be connected of the wiring pattern 4a is brought into contact with the step wall surface 10 c. As means for disposing the electronic control board 4 at the above-described predetermined position of the lower surface 10a at the bonding position 10a1, for example, the suction head 20 shown in fig. 2A may be used, or a suction head different from this may be used.

Further, the flexible substrate 6 placed at the standby position 10a2 can be detachably attached to the lower surface 10a by suction at the standby position 10a2 by applying a negative pressure to the standby suction hole 11. In the standby position 10a2, the flexible substrate 6 is disposed such that the portion to be connected of the wiring pattern 6a formed on the substrate 6 faces downward in the Z-axis direction, and the end portion of the substrate 6 on the side to be connected of the wiring pattern 6a faces the opposite side in the X-axis direction of the electronic control substrate 4. As means for disposing the flexible substrate 6 at the predetermined position on the lower surface 10a at the standby position 10a2, for example, the suction head 20 shown in fig. 2A is used.

In the present embodiment, the step height Z1 of the step wall surface 10c is equal to or less than the thickness t0 of the electronic control board 4, and the difference (t 0-Z1) is preferably 0 to 20 μm, and more preferably 10 to 20 μm.

In the vicinity of the step wall surface 10c, a plurality of second suction holes 14 formed inside the stage 10 open at the high-level side surface 10b of the stage 10. By applying a negative pressure to the second suction hole 14, as shown in fig. 4, the flexible substrate 6 placed on the high-position side surface 10b can be detachably sucked and pre-fixed to the high-position side surface 10b in the vicinity of the step wall surface 10 c. As a means for disposing the flexible substrate 6 on the high-level side surface 10a in the vicinity of the step wall surface 10c, for example, the suction head 20 is used.

Next, an ultrasonic bonding method using the ultrasonic bonding apparatus 2 shown in fig. 2A will be described. As shown in fig. 2B, first, the negative pressure in the standby suction hole 11 opened in the lower surface 10a of the standby position 10a2 is released, and the suction head 20 lifts the flexible substrate 6 located at the standby position 10a2 upward in the Z-axis direction. The suction head 20 has a mechanism for sucking and holding the substrate 6 on the head lower surface by a suction force, for example.

Thereafter, as shown in fig. 3, the suction head 20 is moved in the X-axis direction together with the substrate 6 with respect to the stage 10. Further, the stage 10 may be moved in the X-axis direction. The suction head 20 is relatively moved in the X-axis direction with respect to the stage 10 so that the substrate 6 held by the suction head 20 is positioned on the high-level side surface 10b near the step wall surface 10 c. The movement control is performed by a control unit.

Further, the camera 30 is caused to enter between the wiring pattern 4a and the wiring pattern 6a so that the portion to be connected of the wiring pattern 6a of the substrate 6 and the portion to be connected of the wiring pattern 4a of the substrate 4 are accurately positioned, the positional relationship between these is imaged, and the control unit performs image processing of these. Based on the image processing result, the control unit relatively moves the suction head 20 with respect to the stage 10 in the X-axis and Y-axis directions so that the portions to be connected to the wiring pattern 6a of the substrate 6 and the portions to be connected to the wiring pattern 4a of the substrate 4 are accurately positioned. Further, the control unit may control the moving mechanism to rotate the suction head 20 around the axis of the suction head with respect to the stage 10, as necessary.

Next, the camera 30 moves in the X-axis direction from between the substrate 6 and the stage 10, and is retracted to a position where the movement of the suction head 20 in the Z-axis direction is not hindered. Thereafter, as shown in fig. 4, the suction head 20 approaches the high-position side surface 10b of the stage 10, releases the suction holding of the substrate 6, and places the substrate 6 on the high-position side surface 10 b. At the same time, negative pressure is applied to the second suction holes 14, and the substrate 6 is sucked and held on the high-level side surface 10 b. In this state, the lower surface of the end portion of the substrate 6 in the X-axis direction and the upper surface of the end portion of the substrate 4 in the X-axis direction overlap each other, and a laminated portion is formed at a position corresponding to the step wall surface 10 c. In the laminated portion, the portion to be bonded of the wiring pattern 4a and the portion to be bonded of the wiring pattern 6a are opposed to each other.

Next, as shown in fig. 5A, the stage 10 is moved relative to the suction head 20 and the camera 30 in the X-axis direction, and the pressing portion 52a of the ultrasonic transducer unit 50 is positioned directly above the Z-axis direction of the laminated portion of the wiring patterns 6a and 4 a. Further, the X-axis relative movement of the stage 10 and the ultrasonic transducer unit 50 is controlled in advance so that the pressing portion 52a of the ultrasonic transducer unit 50 is positioned on the lower side surface 10a within a predetermined range X3 in the X-axis direction with respect to the step wall surface 10c of the stage 10.

That is, the movement mechanism is controlled by the control unit so that the pressing portion 52a of the ultrasonic transducer unit 50 presses the laminated portion located on the lower side surface 10a within a predetermined range x3 from the step wall surface 10 c. The predetermined range X3 is preferably larger than 0 and smaller than the X-axis direction length X1 of the laminated portion. That is, the pressing portion 52a is controlled not to press the surface of the substrate 6 located above the high-side surface 10 b.

The length X1 in the X-axis direction of the laminated portion is required to be equal to the overlapping length of the portions to be connected of the wiring patterns 4a and 6a, and is, for example, as small as 0.5mm or less, preferably 0.2mm or less. The length X2 in the X-axis direction of the pressing portion 52a pressing the overlapping portion (laminated portion) of the substrates 4 and 6 is preferably equal to or greater than the length X1 in the X-axis direction of the laminated portion, and the difference in length (X2-X1) is preferably 0 or greater and 0.5mm, and more preferably 0.01 to 0.08 mm.

Next, as shown in fig. 5A to 5B, the ultrasonic transducer unit 50 is moved downward in the Z-axis direction relative to the stage 10, the pressing portion 52a of the ultrasonic transducer unit 50 is pressed against the laminated portion of the substrates 4 and 6, and a pressing force in the Z-axis direction and ultrasonic vibration in the X-axis direction are applied to the laminated portion. As a result, the metals of the wiring patterns 4a and 6a of the laminated portion, which are long in the X-axis direction and arranged at a predetermined pitch in the Y-axis direction, are solid-state bonded to each other by ultrasonic waves.

The metal constituting the wiring patterns 4a and 6a is not particularly limited as long as it is a metal (including an alloy) capable of ultrasonic bonding, and silver, gold, aluminum, an alloy containing these as main components, or the like are exemplified. Further, an oxidation preventing film containing titanium or the like as a main component may be formed on the surface of these metals (particularly, the surface of aluminum).

In the method of manufacturing the substrate assembly 8 according to the present embodiment (including the ultrasonic bonding method), since the step wall surface 10c is provided on the surface of the stage 10, the electronic control board 4 and the flexible board 6 can be easily positioned by the step wall surface 10c, and the wiring patterns 4a and 6a can be ultrasonically bonded to each other. Therefore, even when the pitch interval between the wirings in the Y-axis direction is narrow to about several tens μm or less, for example, short-circuit failure or the like does not occur, and the electronic control board 4 and the flexible board 6 are easily electrically connected to each other. It is preferable that the direction of the ultrasonic vibration is not the lamination direction (Z-axis direction) of the laminated portion but a direction along the longitudinal direction of the bonded wiring patterns 4a and 6 a.

Further, recently, as in a display screen of a smartphone or the like, a display screen as large as the outer size of the housing of the device is required, and therefore, the bonding length x1 between the wiring patterns 4a and 6a also has to be shortened, which causes a problem in connection reliability. According to the method of the present embodiment, solid-state bonding of metals to each other can be performed by ultrasonic bonding, and the reliability of connection is also improved.

In the method of manufacturing the substrate assembly according to the present embodiment, since the step wall surface 10c is provided on the surface of the stage 10, the wiring patterns can be reliably ultrasonically bonded to each other even when the width in the Y-axis direction of the laminated portion of the electronic control board 4 and the flexible substrate 6 is, for example, 60mm or more.

In the present embodiment, the moving mechanism is controlled by the control unit so that the pressing portion 52a of the ultrasonic transducer unit 50 presses the laminated portion located on the lower side surface 10a within a predetermined range from the step wall surface 10 c. The pressing portion 52a of the ultrasonic transducer unit 50 preferably presses only the laminated portion without pressing the flexible substrate 6 located on the high-side surface 10b, and preferably performs ultrasonic bonding. With this configuration, disconnection of the wiring patterns and the like do not occur, and the reliability of ultrasonic bonding between the wiring patterns 4a and 6a is further improved.

Other modifications

The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention.

For example, the electronic control board 4 may be a flexible board having flexibility, in addition to a rigid board including a glass board.

In the above-described embodiment, the flexible substrate 6 is used as the second planar member, but the second planar member is not particularly limited.

In the present invention, the joining target portion is not limited to the joining target portion between the substrates, but may be applied to ultrasonic joining of a joining target portion other than the substrates. As bonding other than the substrate, the present invention can be applied to bonding of semiconductor elements such as cmos sensors, CCD sensors, and LEDs. The ultrasonic bonding head and the ultrasonic bonding apparatus of the present invention are particularly effective when used for bonding substrates to each other. This is because, when substrates are bonded to each other, it is necessary to increase the width of the region to be bonded, and the device is conventionally easily large-sized.

In the above-described embodiment, the stage 10 having the step wall surface 10c is used as the stage, but a general stage having no step wall surface may be used. In addition, the ultrasonic bonding head according to the present invention may not necessarily have a stage.

In the above-described embodiment, the holder 60 holds the booster 54, but may hold the vibration node portion of the ultrasonic horn 52. The suppression pin 60 may be in contact with the booster 54, not in contact with the ultrasonic horn 52. The transducer unit may be a combination of the ultrasonic horn 52, the booster 54, and the vibration source, or may be a transducer unit without the booster 54.