JP2005219070A - Connecting method, connecting structure, connecting device, method of producing droplet discharge head, droplet discharge head and droplet discharge device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connecting method, a connecting structure and a connecting device where the quality in connecting can be improved, to provide a droplet discharge head having high reliability, to provide a method for producing a droplet discharge head, and to provide a droplet discharge device. <P>SOLUTION: The connecting device 400 is provided with: a diffraction apparatus 402 arranged in such a manner that a laser beam is almost vertically made incident; a galvanometer mirror 403 arranged so as to be confronted with the diffraction apparatus 402; and a condenser lens 404 arranged in the reflective orientation of a laser beam in the galvanometer mirror 403. The region on which a connected part in the connecting structure 405 shall be formed is scanned by a laser beam with a prescribed intensity distribution, and energy having an ununiform distribution at each portion of the connected part is applied, thus a metal 120 for connection interposed between a lead electrode 90 and external wiring 111 is melted, so as to connect an electrode part 310 and an external wiring cable 110. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a bonding method, a bonding structure, a bonding apparatus, a method for manufacturing a droplet discharge head, a droplet discharge head, and a droplet discharge apparatus.

  Conventionally, when connecting a terminal group having a plurality of terminals drawn out from individual electrodes of a piezoelectric element in an ink jet recording head to an external wiring cable made of a flexible printed cable (FPC) or the like, the external wiring cable In a state where the plurality of terminals included in the plurality of terminals and the plurality of terminals drawn out from the piezoelectric element are respectively in a corresponding arrangement, they are joined by soldering using a heating means such as a heater that is in contact with the external wiring cable side. It was. However, when such a method is used, there is a problem that deformation or cracking is likely to occur in a substrate or the like provided with a piezoelectric element due to heating during bonding.

  Therefore, in recent years, for the purpose of preventing the above-described deformation and cracking, laser light is irradiated from the external wiring cable side and held between the terminal provided in the external wiring cable and the terminal drawn out from the piezoelectric element. A joining method has been developed in which solders are electrically melted by heating and melting them (see, for example, Patent Document 1). In this bonding method, a method of irradiating a laser beam for each region to be connected, or a method of irradiating continuously by moving the laser beam is adopted.

However, in the above-described method of irradiating laser light to each region to be connected, it is necessary to relatively move the member to be connected and the laser light source, and to repeatedly turn on and off the laser light. There is a problem that the productivity is inferior and, as a result, the cost of the product becomes high.
Further, in the method of continuously irradiating by moving the laser beam, the laser beam is moved at a constant speed so that the irradiation energy to each part is uniform. However, even if the laser beam is irradiated so that the irradiation energy to each part is sufficiently uniform, the bonding state at each part varies, and it is difficult to sufficiently improve the bonding reliability.

JP 2003-630006 A (page 6, right column, lines 29-37)

  An object of the present invention is to provide a bonding method, a bonding structure, and a bonding apparatus capable of improving bonding quality, and a highly reliable droplet discharge head, a method for manufacturing a droplet discharge head, and a droplet discharge To provide an apparatus.

Such an object is achieved by the present invention described below.
The bonding method of the present invention includes a first terminal group including a plurality of first terminals arranged in parallel to each other, and a plurality of second terminals arranged corresponding to each of the first terminals. A joining method for joining the second terminal group provided,
It is a method of joining the first terminal group and the second terminal group by scanning a laser beam at least along the arrangement direction of the terminals,
The laser light exhibits a predetermined intensity distribution along the scanning direction, and the length of the predetermined intensity distribution in the scanning direction is at least equal to or less than the length in the arrangement direction of the terminal group,
The energy distribution of the laser beam given by the scanning is non-uniform at each part in the arrangement direction,
The plurality of first terminals and the plurality of second terminals corresponding to the plurality of first terminals are electrically connected to each other by the laser light. It is characterized by joining.
Thereby, the joining method which can improve the quality of joining can be provided. In particular, it is possible to provide a bonding method that can improve the reliability of bonding while reducing the number of scans to reduce the cost of bonding.

In the joining method of the present invention, it is preferable that the predetermined intensity distribution is asymmetric with respect to the scanning direction.
Thereby, it is possible to prevent and suppress a rapid temperature rise in the terminal group irradiated with the laser beam, and to suppress bumping of the connecting metal, for example. As a result, it is possible to more effectively prevent a bonding failure or a short circuit from occurring in the bonding.

In the bonding method of the present invention, it is preferable that the laser light is reflected by a reflecting means having a function of changing the reflection direction of the incident laser light with time.
Thereby, the laser beam can be easily scanned along the arrangement direction of the terminals.
In the bonding method according to the aspect of the invention, it is preferable that the reflection unit changes the reflection direction of the laser light by rotating or rotating a reflector that reflects the laser light.
Thereby, the laser beam which exhibits desired energy distribution can be irradiated comparatively easily.

In the joining method of the present invention, the reflecting means is preferably a galvanometer mirror.
Thereby, the predetermined energy distribution given by the laser beam can be formed more easily, and even if the energy distribution to be given is changed, the changed energy distribution can be easily dealt with.
In the joining method of the present invention, the reflecting means is preferably a polygon mirror.
Thereby, while being able to form the predetermined energy distribution which a laser beam gives more easily, the continuous processing of a some board | substrate can be performed suitably and the efficiency of a joining process can be improved.

In the bonding method of the present invention, it is preferable that the laser light is diffracted in a desired direction by a diffraction unit having a function of diffracting the incident laser light.
Thereby, the predetermined intensity distribution (energy distribution) can be easily formed.
In the bonding method of the present invention, it is preferable that the laser beam is refracted in a desired direction by a refracting unit having a function of refracting the incident laser beam.
As a result, the predetermined intensity distribution (energy distribution) can be easily formed, and other condensing means are not required, and the bonding cost can be further reduced.

In the bonding method of the present invention, it is preferable that the intensity of the laser beam incident on the reflecting means is changed over time.
Thereby, the predetermined energy distribution given by the laser beam can be easily formed.
In the bonding method of the present invention, it is preferable to control the irradiation time of the laser beam irradiation site to be different at each site in the scanning direction.
Thereby, a predetermined energy distribution can be formed with a smaller number of scans.

In the bonding method of the present invention, the intensity of the laser beam applied to the portion corresponding to the first terminal arranged near the end in the arrangement direction of the first terminal group is the first terminal. It is preferable that the intensity of the laser beam applied to a portion corresponding to the first terminal arranged near the center of the group in the arrangement direction is larger than the intensity of the laser beam.
As a result, it is possible to further reduce variation in energy received by each terminal constituting the terminal group (finally received energy) and variation in temperature of each terminal constituting the terminal group. As a result, the first terminal group can be reduced. And the reliability of the joint between the second terminal group can be further increased.

In the bonding method according to the aspect of the invention, it is preferable that the laser light has a distribution in which the irradiation intensity continuously changes in the scanning direction.
Thereby, even when the accuracy of alignment between the irradiated laser beam and the terminal group to be joined (first terminal group, second terminal group) is relatively low, the joining reliability is sufficient. Can be expensive.

In the bonding method of the present invention, it is preferable that the laser beam is a semiconductor laser.
Thereby, it is possible to easily and reliably control the emission conditions of the emitted laser light. Further, it is possible to easily and reliably control the energy distribution given by the laser light (energy distribution given to each part of the scanning region), the irradiation pattern, and the like.

In the bonding method of the present invention, it is preferable that the temperature of the first terminal group and / or the second terminal group is measured and the intensity of the laser beam is controlled according to the measured temperature.
Thereby, the dispersion | variation in the temperature of each terminal which comprises a terminal group at the time of joining can be made smaller, As a result, the reliability of joining of a 1st terminal group and a 2nd terminal group is further improved. Can do.

In the bonding method of the present invention, the wavelength of the laser light is preferably 800 to 900 nm.
Thereby, the utilization efficiency of the energy given by the laser can be made particularly excellent, and the temperature at each part of the terminal group can be controlled more reliably.
In the bonding method of the present invention, it is preferable that the laser light is irradiated in a state where a brazing material is disposed between the first terminal and the second terminal.
As a result, the first terminal group and the second terminal group can be joined with a relatively low energy amount, and the joining reliability of the formed joint portion can be made sufficiently high. .

In the bonding method of the present invention, when the melting point of the brazing material is T [° C.], the temperature of the first terminal group and the second terminal group when irradiating the laser beam is (T + 50) It is preferable that it is below ℃.
Thereby, generation | occurrence | production of the bad influence by high temperature can fully be prevented, and the joining reliability of the junction part formed can be made high.

In the joining method of the present invention, it is preferable to directly join the first terminal and the second terminal without using a brazing material.
Thereby, the influence of the thickness of the brazing material and the variation thereof can be eliminated, and the variation in the distance between the first terminal and the second terminal at the time of joining is represented by a terminal group (first terminal group, second terminal group). The entire terminal group) can be made smaller. As a result, it is possible to further improve the bonding reliability of the formed bonding structure.

In the joining method of the present invention, it is preferable that in the first terminal group, the plurality of first terminals are arranged at substantially equal intervals.
Thereby, the heat conduction in the vicinity of the first terminal group and the resulting temperature profile can be predicted easily and appropriately, and the temperature at each part of the terminal group can be controlled more reliably. In addition, alignment between the first terminal group and the second terminal group can be performed easily and reliably.

The joining structure of the present invention is characterized in that the first terminal group and the second terminal group are joined by the joining method of the present invention.
Thereby, it is possible to provide a bonded body with high bonding reliability while reducing the bonding cost.
The joining device of the present invention includes a first terminal group including a plurality of first terminals arranged in parallel to each other, and a plurality of second terminals arranged corresponding to each of the first terminals. A joining device for joining the second terminal group provided,
Laser light emitting means for emitting laser light;
Scanning means for scanning at least the terminal group along the arrangement direction of the terminals with the laser light emitted from the laser light emitting means;
The laser light exhibits a predetermined intensity distribution along the scanning direction, and the length of the predetermined intensity distribution in the scanning direction is at least equal to or less than the length in the arrangement direction of the terminal group,
The energy distribution of the laser beam given by the scanning is non-uniform at each part in the arrangement direction,
The plurality of first terminals and the plurality of second terminals corresponding to the plurality of first terminals are electrically connected to each other by the laser light. It is characterized by joining.
Thereby, it is possible to provide a bonding apparatus that can improve the reliability of bonding while reducing the cost of bonding.

In the bonding apparatus of the present invention, a lens unit is provided on the optical path of the laser beam,
It is preferable that the first terminal group and the second terminal group are joined by the laser light emitted from the lens unit.
Thereby, the effect that the laser beam of predetermined intensity distribution (energy distribution) can be obtained easily is acquired.

In the bonding apparatus according to the aspect of the invention, it is preferable that the scanning unit is a galvanometer mirror.
Thereby, the predetermined energy distribution given by the laser beam can be formed more easily, and even if the energy distribution to be given is changed, the changed energy distribution can be easily dealt with.
In the joining apparatus of the present invention, it is preferable that the scanning means is a polygon mirror.
Accordingly, a predetermined energy distribution of the laser beam can be formed more easily, and a plurality of substrates can be continuously processed, and the efficiency of the bonding process can be improved.

In the bonding apparatus of the present invention, it is preferable to include irradiation intensity varying means for changing the intensity of the laser light with time.
Thereby, the predetermined energy distribution of the laser beam can be easily formed.
The method for manufacturing a droplet discharge head according to the present invention is characterized in that the droplet discharge head is manufactured using the bonding method according to the present invention.
As a result, it is possible to provide a droplet discharge head that has excellent bonding quality and high reliability.

The method for manufacturing a droplet discharge head according to the present invention is characterized in that a droplet discharge device is manufactured using the bonding apparatus according to the present invention.
As a result, it is possible to provide a droplet discharge head that has excellent bonding quality and high reliability.
The droplet discharge head of the present invention is manufactured using the manufacturing method of the present invention.
As a result, it is possible to provide a droplet discharge head that has excellent bonding quality and high reliability.
A droplet discharge apparatus according to the present invention includes the droplet discharge head according to the present invention.
As a result, it is possible to provide a droplet discharge device with excellent bonding quality and high reliability.

Hereinafter, preferred embodiments of a bonding method, a bonding structure, a bonding apparatus, a method for manufacturing a droplet discharge head, a droplet discharge head, and a droplet discharge apparatus according to the present invention will be described.
First, prior to the description of the bonding method, the bonding structure and the bonding apparatus of the present invention, an ink jet recording head as an example of the apparatus having the bonding structure of the present invention, an apparatus manufactured using the method, the bonding apparatus of the present invention. (Droplet discharge head) will be described.

  1 is an exploded perspective view showing an ink jet recording head (droplet discharge head) to which the present invention is applied, FIG. 2 is a plan view showing the ink jet recording head of FIG. 1, and FIG. FIG. 3 is a cross-sectional view of the pressure generation chamber in the ink jet recording head of FIG. 1, FIG. 3A is a cross-sectional view in the longitudinal direction of the pressure generation chamber, and FIG. 3B is a line A- in FIG. It is sectional drawing which follows A '.

As shown in FIG. 1, the ink jet recording head (droplet discharge head) 1000 includes a flow path forming substrate 10, a nozzle plate 20, a lower electrode film 60, a piezoelectric layer 70, an upper electrode film 80, A reservoir forming substrate 30 and a compliance substrate 40 are provided.
In this embodiment, the flow path forming substrate (substrate) 10 is composed of a silicon single crystal substrate having a plane orientation (110). As the flow path forming substrate 10, one having a thickness of about 150 to 300 μm is usually used, preferably about 180 to 280 μm, more preferably about 220 μm. Thereby, arrangement density can be made high, maintaining the rigidity of partition 11 between the below-mentioned pressure generating chambers which adjoin.

One surface (main surface) of the flow path forming substrate 10 is an opening surface, and an elastic film 50 formed integrally with the flow path forming substrate 10 is provided on the other surface side. The elastic film 50 is formed by subjecting silicon to thermal oxidation, and is made of silicon dioxide. The thickness of the elastic film 50 is not particularly limited, but is preferably about 1 to 2 μm.
On the other hand, pressure generating chambers 12 partitioned by a plurality of partition walls 11 are arranged side by side in the width direction on the opening surface side of the flow path forming substrate 10. A communication portion 13 is formed which forms a part of the reservoir 100 that communicates and serves as a common ink chamber for each pressure generation chamber 12. The communication portion 13 includes one end portion in the longitudinal direction of each pressure generation chamber 12 and each ink. Communication is made via a supply path 14. The pressure generating chamber 12, the communication portion 13, and the ink supply path 14 are formed by performing anisotropic etching on a silicon single crystal substrate.

  Here, in the anisotropic etching, when the silicon single crystal substrate is immersed in an alkaline solution such as KOH, the first (111) plane perpendicular to the (110) plane is gradually eroded and the first (111) ) Plane and a second (111) plane that forms an angle of about 70 degrees with the (110) plane and appears at an angle of about 35 degrees, compared with the etching rate of the (110) plane (111 This is performed utilizing the property that the etching rate of the surface is about 1/180. By this anisotropic etching, a parallelogram shape formed by two first (111) planes and two second (111) planes oblique to the first (111) plane Precision processing can be performed based on depth processing, and the pressure generating chambers 12 can be arranged with high density.

  In the present embodiment, the long side of each pressure generating chamber 12 is formed by the first (111) plane and the short side is formed by the second (111) plane. The pressure generation chamber 12 is formed by etching until it substantially passes through the flow path forming substrate 10 and reaches the elastic film 50. Here, the amount of the elastic film 50 that is affected by the alkaline solution for etching the silicon single crystal substrate is extremely small. In addition, each ink supply path 14 communicating with one end of each pressure generation chamber 12 is formed shallower than the pressure generation chamber 12, and the flow path resistance of the ink flowing into the pressure generation chamber 12 is kept constant. That is, the ink supply path 14 is formed by etching the silicon single crystal substrate halfway in the thickness direction (half etching). Half-etching can be performed by adjusting the etching time.

Further, on the opening surface side of the flow path forming substrate 10 (surface opposite to the surface on which the elastic film 50 is provided), in the vicinity of the end of each pressure generating chamber 12 on the side opposite to the ink supply path 14. A nozzle plate 20 having a nozzle opening 21 communicating therewith is fixed through an adhesive, a heat welding film, or the like. The nozzle plate 20 has a thickness of, for example, 0.1 to 1 mm, a linear expansion coefficient of 300 ° C. or less, and, for example, 2.5 to 4.5 × 10 ⁻⁶ / ° C. (Stainless steel) or the like. The nozzle plate 20 entirely covers one surface of the flow path forming substrate 10 on one surface, and also serves as a reinforcing plate that protects the silicon single crystal substrate from impact and external force. Further, the nozzle plate 20 may be formed of a material having substantially the same thermal expansion coefficient as that of the flow path forming substrate 10. In this case, since the deformation by heat of the flow path forming substrate 10 and the nozzle plate 20 is substantially the same, it can be easily joined using a thermosetting adhesive or the like.

  Here, the size of the pressure generating chamber 12 that applies ink droplet discharge pressure to the ink and the size of the nozzle opening 21 that discharges the ink droplet are optimized according to the amount of ink droplet to be discharged, the discharge speed, the discharge frequency, and the like. Is done. For example, when 360 ink droplets are recorded per inch, it is preferable that the nozzle opening 21 is accurately formed with a diameter of several μm to several tens of μm (more specifically, about 20 μm).

  On the other hand, on the surface of the elastic film 50 opposite to the surface facing the flow path forming substrate 10, a lower electrode film 60 having a thickness of, for example, about 0.2 μm and a piezoelectric film having a thickness of, for example, about 1 μm. The body layer 70 and an upper electrode film 80 having a thickness of, for example, about 0.1 μm are stacked by film formation and lithography to form the piezoelectric element 300. Here, the piezoelectric element 300 refers to a portion including the lower electrode film 60, the piezoelectric layer 70, and the upper electrode film 80. In general, one electrode of the piezoelectric element 300 is used as a common electrode, and the other electrode and the piezoelectric layer 70 are patterned for each pressure generating chamber 12. In addition, here, a portion that is configured by any one of the patterned electrodes and the piezoelectric layer 70 and in which piezoelectric distortion is generated by applying a voltage to both electrodes is referred to as a piezoelectric active portion. In the present embodiment, the lower electrode film 60 is used as a common electrode of the piezoelectric element 300 and the upper electrode film 80 is used as an individual electrode of the piezoelectric element 300. However, there is no problem even if this is reversed for convenience of a drive circuit and wiring. In either case, a piezoelectric active part is formed for each pressure generating chamber. Further, here, the piezoelectric element 300 and the vibration plate that is displaced by driving the piezoelectric element 300 are collectively referred to as a piezoelectric actuator. In the example described above, the elastic film 50 and the lower electrode film 60 act as a diaphragm, but the lower electrode film may also serve as the elastic film.

  A reservoir forming substrate 30 having a reservoir portion 31 constituting at least a part of the reservoir 100 is joined to the surface of the flow path forming substrate 10 on which the piezoelectric element 300 is provided. In this embodiment, the reservoir portion 31 is formed across the reservoir forming substrate 30 in the thickness direction and across the width direction of the pressure generating chamber 12, and as described above, the communication portion of the flow path forming substrate 10 is formed. The reservoir 100 is connected to the pressure generation chamber 12 and serves as a common ink chamber for the pressure generation chambers 12.

  The reservoir forming substrate 30 is preferably made of substantially the same material as the coefficient of thermal expansion of the flow path forming substrate 10, for example, glass, ceramic material, etc. In this embodiment, it is the same as the flow path forming substrate 10. It is composed of a silicon single crystal substrate of material. Thereby, like the case of the above-mentioned nozzle plate 20, even if it is the adhesion | attachment at high temperature using a thermosetting adhesive agent, both can be adhere | attached reliably. Therefore, the manufacturing process can be simplified.

The reservoir forming substrate 30 is bonded to the lower electrode film 60 in the illustrated configuration, but may be bonded to the elastic film 50 or directly bonded to the flow path forming substrate 10. It may be.
Furthermore, a compliance substrate 40 including a sealing film 41 and a fixing plate 42 is bonded to the reservoir forming substrate 30. Here, the sealing film 41 is made of a material having low rigidity and flexibility (for example, a polyphenylene sulfide (PPS) film having a thickness of about 6 μm). Is sealed. The fixing plate 42 is made of a hard material such as metal (for example, stainless steel (SUS) having a thickness of about 30 μm). Since the region of the fixing plate 42 facing the reservoir 100 is an opening 43 that is completely removed in the thickness direction, one surface of the reservoir 100 is sealed only with a flexible sealing film 41. A region corresponding to the opening 43 of the sealing film 41 is a flexible portion 25 that can be deformed by a change in internal pressure.

  An ink introduction port 44 for supplying ink to the reservoir 100 is formed on the compliance substrate 40 on the outer side of the central portion of the reservoir 100 in the longitudinal direction. Further, the reservoir forming substrate 30 is provided with an ink introduction path 36 that allows the ink introduction port 44 and the side wall of the reservoir 100 to communicate with each other. In the present embodiment, ink is supplied to the reservoir 100 by one ink introduction port 44 and the ink introduction path 36, but the present invention is not limited to this. For example, according to a desired ink supply amount, A plurality of ink introduction ports and ink introduction paths may be provided, or the ink flow path may be enlarged by increasing the opening area of the ink introduction port.

  Normally, when ink is supplied from the ink introduction port 44 to the reservoir 100, a pressure change occurs in the reservoir 100 due to, for example, the flow of ink when the piezoelectric element 300 is driven or ambient heat. However, as described above, since one surface of the reservoir 100 is sealed only by the sealing film 41 to form the flexible portion 25, the flexible portion 25 is bent and deformed to absorb the pressure change. Therefore, the inside of the reservoir 100 is always maintained at a substantially constant pressure. The other portions are held at a sufficient strength by the fixing plate 42. Further, in this embodiment, since the number of substrates constituting the reservoir 100 and the like can be reduced, material costs, assembly costs, and the like can be reduced.

On the other hand, in a region facing the piezoelectric element 300 of the reservoir forming substrate 30, a piezoelectric element holding portion 32 capable of sealing the space is provided in a state where a space that does not hinder the movement of the piezoelectric element 300 is secured. The element 300 is sealed in the piezoelectric element holding portion 32.
As described above, the reservoir forming substrate 30 constitutes the reservoir 100 and also serves as a cap member for blocking the piezoelectric element 300 from the external environment. The piezoelectric element 300 is deteriorated, broken, or damaged by the external environment such as moisture. Etc. can be prevented. Here, the inside of the piezoelectric element holding part 32 is only sealed, but for example, the space in the piezoelectric element holding part 32 is evacuated, or the piezoelectric element is kept in a nitrogen or argon atmosphere or the like. The inside of the holding unit 32 can be held at low humidity, and deterioration, failure, breakage, and the like of the piezoelectric element 300 can be further reliably prevented.

  In addition, a lead-out wiring extends from the piezoelectric element 300 sealed by the piezoelectric element holding portion 32 in this way, and is connected to an external wiring cable 110 such as a flexible printed cable (FPC) in the vicinity of the end portion. For example, in the present embodiment, a lead electrode (first terminal) 90 that is a lead-out wiring extends from the upper electrode film 80 of the piezoelectric element 300 to the vicinity of the end of the flow path forming substrate 10. Since the lead electrodes 90 are provided corresponding to the respective piezoelectric elements 300, a plurality of lead electrodes 90 are provided on the flow path forming substrate 10, and the plurality of lead electrodes 90 are arranged in parallel to each other to form an electrode portion (first terminal group). ) 310 is formed. On the other hand, the external wiring cable 110 has an external wiring (wiring pattern) 111 having a plurality of ends and a coating film 112 covering the external wiring 111. The external wiring 111 has a terminal (second terminal) 1111 connected to each lead electrode 90 in the vicinity of the plurality of ends. The plurality of terminals 1111 are arranged in parallel with each other so as to correspond to each of the lead electrodes 90 constituting the electrode portion 310 to form a terminal group (second terminal group) 113. And each lead electrode 90 which comprises the electrode part 310 mentioned above is electrically connected to each terminal 1111 corresponding to each. That is, in this embodiment, the vicinity of the end of the lead electrode 90 is a connection terminal (first terminal) for driving the piezoelectric element 300, and a terminal (second terminal) 1111 is connected to this connection terminal. Has been.

  Moreover, the coating film 112 is normally comprised with the material excellent in the transmittance | permeability of laser beams, such as a polyimide (PI). As a result, when using a bonding apparatus and bonding method as described later, the energy of the laser beam can be used more efficiently for bonding the lead electrode 90 and the terminal 1111, and the bonding reliability is excellent. The bonded structure 405 can be reliably formed in a shorter time.

  The connection (bonding) between the lead electrode 90 and the terminal 1111 as described above can be performed by a bonding method and a bonding apparatus as described later. More specifically, the bonding is performed through the connection metal 120 melted by the laser beam. The connecting metal 120 may be any material that can withstand a high current applied when the piezoelectric element 300 is driven at a high speed, and the material is not particularly limited, but is mainly a brazing material. Is preferred. The brazing filler metal melts at a relatively low temperature, is excellent in conductivity, and is easily available. As the brazing material, for example, Pb-containing solder such as Pb—Sn solder, Sn—Ag—Cu solder, Sn—Zn solder, Sn—Cu solder, Sn—Bi solder, etc. Pb-free lead (Pb-free solder), silver brazing, copper brazing, phosphor copper brazing, brass brazing, aluminum brazing, nickel brazing, etc. Of these, solders such as Pb-containing solder and lead-free solder (Pb-free solder) are preferable. Lead-free solder (Pb-free solder) is particularly advantageous from the viewpoint of both joint strength and environmental impact. Further, since the durable current is large compared to the joining using the connecting metal 120 as described above and the joining using the anisotropic conductive adhesive (ACF), it can withstand a large current due to high-speed driving. In addition, since the connecting metal 120 as described above is disposed between the lead electrode 90 and the terminal 1111, the lead electrode 90 and the terminal 1111 can be connected with a relatively low energy amount in a joining method as described later. Can be bonded, and the bonding reliability of the formed bonding structure (bonding portion) 405 can be made particularly high.

Next, a bonding method, a bonding structure, a bonding apparatus, a droplet discharge head manufacturing method, and a droplet discharge head according to a first embodiment of the present invention will be described.
FIG. 4 is a diagram illustrating a schematic configuration of the bonding apparatus and the bonding structure according to the present embodiment, and FIG. 5 illustrates laser light (reflection) that irradiates a plurality of stacked structures in which the bonding apparatus according to the present embodiment is arranged in parallel. FIG. 5A is a diagram showing a laser beam having a predetermined intensity distribution to be irradiated, and FIG. 5B is a diagram showing a change in the intensity of the laser beam during scanning. FIG. 5C is a diagram showing the distribution of the amount of thermal energy given to the laminated structure (terminal group) by the scanning of the laser beam. FIG. 6 is a process cross-sectional view illustrating a bonding method and a manufacturing method of a droplet discharge head according to the present embodiment. 5A and 5B, the vertical axis and the horizontal axis indicate the intensity of the laser beam and the position in the longitudinal direction of the terminal row, respectively. The vertical axis and horizontal axis in FIG. The axes indicate the energy of the laser beam applied to each part and the position in the longitudinal direction of the terminal row, respectively.

  As shown in FIG. 4, the bonding apparatus 400 includes a laser light generator (laser light emitting means) 401 as a laser light source that irradiates laser light as parallel light, and the laser light (laser light as parallel light). A diffractive device (diffractive means) 402 arranged so as to be incident substantially perpendicularly, and a galvanometer mirror (scanning means, reflecting means) 403 arranged opposite to the surface opposite to the laser light incident surface of the diffractive device 402. And a condensing lens 404 arranged in the reflection direction (reflection direction) of the laser light of the galvanometer mirror 403.

  The laser light generation device 401 is a semiconductor laser irradiation device (semiconductor laser irradiation means) provided with a laser diode such as gallium arsenide, for example, and the wavelength of the irradiated laser light is 800 to 900 nm. When the laser beam emitted from the laser beam generator 401 is a semiconductor laser, it is possible to easily and reliably control the emission conditions of the laser beam emitted toward the diffraction device 402. In addition, it is possible to easily and reliably control the energy distribution (distribution of energy given to each part of the scanning region), the irradiation pattern, and the like given by the reflected laser light described later. In addition, when the wavelength of the laser beam emitted from the laser beam generator 401 is 800 to 900 nm, the laser energy utilization efficiency can be made particularly excellent, and the electrode portion (first terminal group). The temperature in each part of 310 and the terminal group (2nd terminal group) 113 can be controlled more reliably. Note that the laser light emitted by the laser light generating device 401 is not limited to the above, and for example, an infrared light region laser, a gas laser, a metal vapor laser, or the like may be used. As the laser light generator 401, any of those capable of arbitrarily changing the intensity of the laser light to be irradiated (which can be changed with time) and those which emit laser light having a substantially constant intensity are available. Can be used. As the laser light generator 401, an apparatus capable of arbitrarily changing the intensity of the laser light to be irradiated (equipped with an irradiation intensity variable means) has a relatively complicated energy distribution given by the reflected laser light described later. Even so, such an energy distribution can be formed relatively easily. In addition, the laser beam generator 401 that emits a laser beam having a substantially constant intensity is advantageous in terms of cost.

  The diffractive device 402 includes, for example, a diffractive optical element, diffracts the laser light incident from the laser light generating device 401, and converts the diffracted laser light (diffracted laser light) into an incident surface. The light is emitted from the opposite side of the surface. A diffractive optical element is a substrate-like object having a grating structure (diffraction grating) composed of periodically formed fine holes, partition walls, and protrusions, and is generated when light is irradiated to the grating structure. Utilizing diffraction, the traveling direction of the incident light is changed. Specifically, the diffracted light generated from the gaps of the respective grating structures are caused to interfere with each other, and strong diffracted light is generated in a predetermined direction in which the interference is strengthened. Since the direction and intensity in which the diffracted light is generated depends on the period of the grating, the transmittance (reflectance), etc., light having a wavefront in a desired direction can be obtained from the incident light by appropriately designing them. For example, it is possible to irradiate the incident light by splitting it in several directions. The diffractive device 402 is also optimally designed so that the incident laser beam is emitted in a desired direction in order to obtain a predetermined intensity distribution of the laser beam to be described later.

  The galvanometer mirror 403 includes a piezo-type galvanometer (not shown) having a platform capable of tilting (turning) in two axial directions controlled with high precision, and a scanning mirror (reflector) 407 attached to the platform. It has. As such a galvanometer, a type of driving a platform using a plurality of piezoelectric transducers can be used.

Piezo-type galvanometers that change the reflection direction (reflection direction) using the piezoelectric effect have the advantages of higher resolution and better response than motor-driven galvanometers. In addition, the biaxial control type is advantageous for performing more complicated and highly accurate processing (joining) than the single axis control type.
Here, the galvanometer mirror 403 is connected to a control device (not shown) for controlling the tilting of the galvanometer, and the laser light generator 401 and the condenser lens 404 are also connected to the control device. The control device is connected to an external computer (not shown) and operates in accordance with instructions from the computer.

  The reflection azimuth (reflection direction) of the scanning mirror 407 in the galvanometer mirror 403 can be continuously changed by changing the tilt angle of the platform by an input signal from the control device instructed by the computer. For this reason, the galvanometer mirror 403 can reflect the laser beam (diffracted laser beam) emitted from the diffractive device 402 and scan the laser beam (reflected laser beam), and further, a desired direction (each part). The reflection time (irradiation time) of the laser beam (reflected laser beam) can be adjusted by controlling the inclination angle change speed of the platform. Therefore, the galvanometer mirror 403 changes the reflection time of the laser beam in accordance with the reflection direction (reflection direction) when scanning the laser beam (reflection laser beam), and scans the laser beam (reflection laser beam) on the scanning line. The energy amount distribution in can be arbitrarily adjusted.

A condensing lens 404 is arranged on the optical path of the laser beam branched in a desired direction reflected by the galvanometer mirror 403. By providing such a condensing lens 404, a laser beam having a predetermined intensity distribution (energy distribution) can be easily formed by forming a plurality of beam spots (condensing points) from the laser light branched in a desired direction. Can get to.
The condensing lens 404 is a biconvex lens, condenses the laser beam branched in a desired direction scanned by the galvano mirror 403, and forms a plurality of beam spots at the focal point, thereby obtaining a predetermined intensity distribution ( A laser beam (reflected laser beam) having an energy distribution is applied to a region where a junction is to be formed.

It should be noted that the peripheral portion of the condensing lens 404 is formed by, for example, a cylindrical lens so that astigmatism or the like does not occur when converging laser light incident in an oblique direction. May be.
With the configuration described above, in the joining device 400, the diffraction device 402, the galvanometer mirror 403, and the condenser lens 404 cooperate to scan the region where the joining portion is to be formed with laser light having a predetermined intensity distribution.

The joining structure 405 is formed by joining the lead electrode 90 and the corresponding terminal 1111 using such a joining apparatus 400. A joining method using the joining apparatus 400 and a manufacturing method of a droplet discharge head will be described in detail later.
The joint structure 405 has a configuration in which the lead electrode 90 and the corresponding terminal 1111 are joined via the connection metal 120. Thereby, the reliability of joining in the joining structure 405 is particularly excellent.

  The joining method of the present invention and the manufacturing method of the droplet discharge head will be described in detail later, but joining of the electrode portion 310 and the terminal group 113 (joining of the plurality of lead electrodes 90 and the corresponding terminals 1111) is performed. In the state where the connecting metal 120 and the terminal 1111 are laminated in this order on the lead electrode 90 to form a laminated structure 406, the electrode unit 310 and the terminal group 113 are bonded to each other with a predetermined intensity distribution using the bonding apparatus 400. Scanning with laser light is performed by applying energy that exhibits non-uniform distribution at each part to the electrode portion 310 and the terminal group 113.

  At this time, a plurality of stacked structures 406 exist. In the present embodiment, the plurality of stacked structures 406 are parallel to each other, and the interval between adjacent stacked structures 406 (distance between adjacent first terminals in the first terminal group, adjacent in the second terminal group). The distance between the second terminals) is approximately equal. Thereby, the heat conduction in the vicinity of the electrode part 310 and the terminal group 113 and the resulting temperature profile can be easily and reliably applied, and the temperature at each part of the joining region can be controlled more reliably. . Further, the alignment between the electrode portion 310 and the terminal group 113 can be easily and reliably performed. Although the specific magnitude | size of the space | interval of the adjacent laminated structure 406 is not specifically limited, It is preferable that it is about 100 micrometers.

By scanning the laminated structure 406 with laser light (reflected laser light), the connecting metal 120 interposed between the lead electrode 90 and the terminal 1111 is melted, and the lead electrode 90 and the terminal 1111 are joined to each other. Is obtained.
Here, as shown in FIG. 5A, the predetermined intensity distribution of the laser light (reflected laser light) applied to the stacked structure 406 extends along the arrangement direction of the multiple stacked structures 406. The length of the predetermined intensity distribution in the extending direction (scanning direction) is equal to or shorter than the length in the arrangement direction of the plurality of stacked structures 406 (the plurality of lead electrodes (first terminals in the electrode portion (first terminal group) 310). Terminal)) or less in the arrangement direction of 90). For this reason, laser beams having a predetermined intensity distribution are not simultaneously irradiated to all the laminated structures 406. Thereby, the laser beam can be suitably scanned, and in particular, the bonding reliability of the bonding structure 405 to be formed can be made sufficiently high while reducing the number of scans.

  The predetermined intensity distribution described above is asymmetric with respect to the scanning direction of the laser light. For example, the intensity gradually increases on the front side in the scanning direction, but rapidly decreases on the rear side. By scanning with a laser beam exhibiting such an intensity distribution, the thermal energy received by a laminated structure 406 is small at first, but gradually increases as scanning progresses. Thereby, for example, a rapid temperature rise in the laminated structure 406 can be effectively prevented, and bumping of the connecting metal 120 can be prevented. Further, since the intensity of the laser beam is rapidly decreased on the rear side in the scanning direction, the temperature of the formed bonding structure 405 is high for a longer time than necessary after the bonding structure 405 is formed. Can be prevented. For this reason, it is possible to effectively prevent the occurrence of inconveniences such as a bonding failure or short circuit between the lead electrode 90 and the terminal 1111.

  In addition, the intensity of the reflected laser light itself changes during the scanning process (with the progress of scanning). Specifically, as shown in FIG. 5B, the intensity of the laser light applied to the laminated structure 406 disposed in the vicinity of the ends of the electrode portion 310 and the terminal group 113 is such that the electrode portion 310 and the terminal group 113 are irradiated. It changes so that it may become larger than the intensity | strength of the laser beam irradiated to the laminated structure 406 distribute | arranged to the center part vicinity. Such a change in the intensity of the laser beam is realized by using a laser beam generator 401 that can arbitrarily change the intensity of the laser beam to be irradiated. In addition, since the intensity of the reflected laser light changes as described above in the scanning process, the distribution of thermal energy received by the plurality of stacked structures 406 is also non-uniform. Specifically, as shown in FIG. 5C, a laminated structure 406 disposed near the ends of the electrode portion 310 and the terminal group 113 (near the end portion in the arrangement direction of the lead electrode 90 and the terminal 1111) receives. The thermal energy is larger than the thermal energy received by the laminated structure 406 disposed in the vicinity of the central portion of the electrode portion 310 and the terminal group 113. Here, “thermal energy” refers to energy directly received by the irradiated laser light, and ignores the influence of heat transfer between the laminated structures 406.

  Then, by scanning with laser light with a non-uniform amount of heat energy to be applied, it is possible to further reduce variations in the thermal energy received by each stacked structure 406 as a whole in the bonding process and variations in the temperature of each stacked structure 406. As a result, it is possible to further improve the reliability of bonding of the respective bonding structures 405 to be formed. This is considered to be due to the following reasons. That is, generally, when heat is generated by laser light irradiation, the generated heat is diffused to the surroundings by heat transfer. In particular, when laser light is irradiated onto a region having a predetermined width (length), heat diffuses toward the center of the region and the direction outside the region near the end of the region. For this reason, when each part of a region having a predetermined width (length) is irradiated with a laser beam having a uniform energy amount, the amount of heat received in the vicinity of the center of the region is larger than that in the vicinity of the end. . As a result, temperature variation occurs in each part of the region. Therefore, when each part of the electrode part 310 and the terminal group 113 (each part in the arrangement direction of the lead electrode 90 and the terminal 1111) is irradiated with a laser beam that gives a uniform energy amount, the amount of heat received by each stacked structure 406 varies. As a result, it is difficult to obtain sufficient bonding reliability in each bonding structure 405 formed. On the other hand, when a laser beam whose energy amount is not uniform is irradiated at each part, the amount of heat received by each stacked structure 406 can be made uniform, and the bonding structure 405 excellent in bonding reliability can be formed.

In this embodiment, the distribution of the amount of thermal energy given to the plurality of stacked structures 406 by the laser light (reflected laser light) irradiated by the bonding apparatus 400 is a continuous distribution in the scanning direction of the laser light. Thereby, even when the alignment accuracy between the laser beam and the bonding structure 405 to be bonded is relatively low, the bonding reliability can be sufficiently high.
The energy distribution as described above can be realized by appropriately selecting the types, configurations, and the like of the diffraction device 402, the galvanometer mirror 403, and the condenser lens 404. In addition, the intensity and energy of the laser light (reflected laser light) irradiated by the bonding apparatus 400 are appropriately selected according to the material, size, and the like of each component constituting the stacked structure 406.

Next, the bonding method and the manufacturing method of the droplet discharge head according to the present embodiment will be described in more detail with reference to FIG.
First, the lead electrode 90 provided on the flow path forming substrate 10 and the terminal 1111 are brought into close contact with each other through the connection metal 120 (FIG. 6A).
At this time, in this embodiment, in order to ensure that the lead electrode 90 and the terminal 1111 are in close contact with each other, for example, a pressing plate 130 made of a material that can transmit laser light is disposed on the upper portion of the terminal 1111. The contact is made by pressing 130 with a predetermined pressure. This predetermined pressure may be generated, for example, by applying a constant static load with a spring or the like, or may be generated by applying a variable load with an actuator or the like. Further, as the pressing plate 130, for example, a plate made of a quartz glass plate or an acrylic plate can be used. The pressing plate 130 may be subjected to various surface treatments such as film formation and liquid repellent treatment. Thereby, it is possible to effectively prevent the coating film 112 and the connecting metal 120 from adhering to the pressing plate 130 when the bonding structure 405 is formed. As a result, it is possible to effectively prevent damage to the formed joint structure 405 and the like when the pressing plate 130 is removed.

The connection metal 120 may be disposed so as to be sandwiched between the lead electrode 90 and the terminal 1111. For example, the connection metal 120 may be previously coated on the surface of the external wiring 111 by various plating methods. Good. Thereby, the alignment of the connecting metal 120 can be omitted or simplified.
Next, a laser having a predetermined intensity distribution as shown in FIG. 5A from the side on which the coating film 112 of the external wiring cable 110 is coated (via the pressing plate 130) by the joining device 400 described above. By scanning with light, the connecting metal 120 interposed between the terminal 1111 and the lead electrode 90 is melted and the lead electrode 90 and the terminal 1111 are joined (FIG. 6B).

  Here, it is preferable that the laser beam irradiated by the bonding apparatus 400 has an appropriate intensity. If the intensity of the laser beam irradiated by the bonding apparatus 400 is too high, the flow path forming substrate 10 may be deformed or cracked by heat. Therefore, when the melting point of the connecting metal 120 is T [° C.], the laminated laser 406 is irradiated with laser light (reflected laser light) so that the laminated structure 406 is (T + 50) ° C. or lower. It is preferable that it is strong. For example, when a solder having a melting point of about 300 ° C. is used as the connection metal 120, it is preferable to irradiate the laser light under such a condition that the temperature of the laminated structure 406 is about 300 to 350 ° C. As a result, deformation and cracking of the flow path forming substrate 10 can be prevented, and extreme heat energy transfer in the flow path forming substrate 10 can be prevented, and the reliability of bonding between the lead electrode 90 and the corresponding terminal 1111 can be prevented. The property can be made particularly excellent.

Further, the lead electrode 90 and the terminal 1111 can be joined to each other with a relatively low energy amount by irradiating the laser light with the connecting metal 120 disposed between the lead electrode 90 and the terminal 1111. In addition, the bonding reliability of the formed bonding structure (bonding portion) 405 can be made particularly high.
The method of adjusting the intensity of the laser beam is not particularly limited, but a temperature measurement unit such as a pyrometer (radiation thermometer) that measures the temperature between the electrode unit 310 and the terminal group 113 is provided, and the measurement result of this temperature measurement unit Accordingly, it is preferable to control the intensity of the laser beam emitted by the laser beam generator 401. Thereby, regardless of the temperature change of the flow path forming substrate 10, appropriate temperature control between each lead electrode 90 and the corresponding terminal 1111 can be easily performed. Further, the temperature variation between the stacked structures 406 (between the bonded structures 405) at the time of bonding can be further reduced, and as a result, the bonding reliability of the bonded structures 405 can be further improved. In particular, in the case of a semiconductor laser, such laser light output control can be performed, for example, in units of 1 msec, so that more appropriate temperature control can be easily performed. Thereby, even if the temperature change of the flow path forming substrate 10 occurs, each lead electrode 90 and the corresponding terminal 1111 can be bonded at a substantially constant temperature, and the bonding state between the lead electrode 90 and the corresponding terminal 1111. Variation of the above can be effectively suppressed, and the bonding reliability of each bonding structure 405 can be further enhanced.

Moreover, since each laminated structure 406 is arranged at equal intervals, the heat conduction in the vicinity of each electrode part 310 and the terminal group 113 and the resulting temperature profile can be controlled easily and reliably. The temperature control in joining the part 310 and the terminal group 113 can be performed more appropriately.
In the above-described bonding apparatus 400, the laser light generator 401 can arbitrarily change the intensity of the laser light to be irradiated (equipped with an irradiation intensity variable unit). However, the laser light generator 401 has a certain intensity. What irradiates the laser beam may be used. At this time, the galvano mirror 403 changes the reflection time of the laser beam in accordance with the reflection direction (reflection direction), and arbitrarily adjusts the energy amount distribution on the scanning line of the scanned laser beam (reflection laser beam). Thereby, the structure of the laser beam generator 401 can be simplified, and the cost of the bonding apparatus 400 can be reduced.

  The above-described joining apparatus 400 includes the galvanometer mirror 403. In the galvanometer mirror, the reflection azimuth (reflection direction) of the scanning mirror 407 and a desired azimuth (direction) are changed by changing a program executed by an external computer. The reflection time (irradiation time) of the laser beam can be easily changed, and as a result, even if the desired energy distribution given by the laser beam is changed, the changed energy distribution can be easily dealt with.

The scanning of the laser light by the galvanometer mirror 403 is normally performed in a reciprocating manner along the arrangement direction of the plurality of stacked structures 406. For example, the laser light irradiated to each stacked structure 406 by adjusting the scanning speed The above scanning may be performed in one step while maintaining the same intensity.
As described above, according to the method and the bonding apparatus of the present embodiment, the connection interposed between the terminal 1111 and the lead electrode 90 by scanning with the laser light (reflected laser light) having a predetermined intensity distribution. Since the working metal 120 is heated and melted to join the lead electrode 90 and the terminal 1111, the movement of thermal energy between the plurality of laminated structures 406 (that is, the movement of thermal energy in the first terminal group and the second terminal group) ) Can be applied to a plurality of stacked structures 406 (terminal groups). As a result, variations in thermal energy received by each stacked structure 406 and variations in temperature between the stacked structures 406 can be further reduced. As a result, the reliability of bonding between the lead electrode 90 and the corresponding terminal 1111 can be improved. It can be made particularly excellent.

  In the present embodiment, the lead electrode 90 and the terminal 1111 are joined on the flow path forming substrate 10. However, the present invention is not limited to this. For example, the reservoir forming substrate 30 may be bonded from the lead electrode 90 by wire bonding or the like. A wiring is provided up to the top, and a part of the wiring on the reservoir forming substrate 30 is used as a connection terminal (first terminal) of the wiring for driving the piezoelectric element 300 so that the wiring and the terminal 1111 are electrically connected. May be.

  In the above description, the lead electrode (first terminal) 90 and the terminal (second terminal) 1111 are described as being joined via the connection metal (brazing material) 120. The lead electrode (first terminal) 90 and the terminal (second terminal) 1111 without the metal 120 (including the lead electrode 90 or a layer formed by plating or the like near the surface of the terminal 1111). And may be directly joined. This eliminates the influence of the thickness of the connecting metal 120 and its variation, and the variation in the distance between the lead electrode (first terminal) 90 and the terminal (second terminal) 1111 during bonding. The terminal group 113 (electrode part 310) can be made smaller throughout. As a result, it is possible to further improve the bonding reliability of the formed bonding structure. In particular, in the present invention, since the energy of the irradiated laser beam can be efficiently used, the target portion (joint portion) can be selectively selected while sufficiently suppressing a temperature rise other than the portion to be the joint portion. The temperature of the part to be) can be raised. Therefore, the connecting metal (brazing material) 120 is not arranged between the lead electrode (first terminal) 90 to be joined and the terminal (second terminal) 1111, and the lead electrode (first terminal) Even if the terminal 90 and the terminal (second terminal) 1111 are made of a relatively high melting point material (for example, Cu), the bonding reliability of the formed bonding structure is particularly excellent. can do. On the other hand, in the conventional method, it is extremely difficult to form a bonding structure with excellent bonding reliability while sufficiently preventing the occurrence of adverse effects due to heat when no bonding metal is used.

  Next, a bonding method, a bonding structure, a bonding apparatus, a droplet discharge head manufacturing method, and a droplet discharge head according to a second embodiment of the present invention will be described. Below, it demonstrates centering around difference with the said 1st Embodiment, The description is abbreviate | omitted about the same matter. Since this embodiment is substantially different from the first embodiment only in the configuration of the reflection means (scanning means), the configuration of the reflection means will be described below.

FIG. 7 is a diagram illustrating a schematic configuration of the bonding apparatus according to the present embodiment.
In FIG. 7, a bonding apparatus 700 includes a laser light generation apparatus 401 that emits laser light, a diffraction apparatus 402 that is arranged so that the laser light is incident substantially perpendicularly, and a laser light incident surface of the diffraction apparatus 402. A polygon mirror 701 disposed opposite to the opposite surface and a condensing lens 404 disposed in the reflection direction of the laser light of the polygon mirror 701 are provided.

  The polygon mirror 701 includes a prismatic prism body 702 having a right prism shape and a side mirror (reflector) 703 that covers the entire surface of each side surface of the prism body 702. The prism body 702 rotates around the central axis by a rotational force transmitted by a motor (not shown) arranged outside. This motor is connected to a control device (not shown) for controlling the rotational speed of the motor, and a laser beam generator 401 and a condenser lens 404 are also connected to the control device. The control device is connected to an external computer (not shown) and operates in accordance with instructions from the computer.

  The reflection direction of the laser light reflected by each side mirror 703 can be continuously changed by rotating the prism body 702 by a motor controlled by the control device. For this reason, the polygon mirror 701 can scan with laser light (reflected laser light). In addition, the reflection time (irradiation time) of the laser beam to a desired direction (each part) can also be adjusted by changing the rotational speed of the prism body 702 or the like. Therefore, the polygon mirror 701 changes the energy distribution on the scanning line of the scanned laser beam by changing the reflection time of the laser beam in accordance with the reflection direction when scanning the laser beam, as shown in FIG. Can be adjusted as follows. Then, by the functions of the laser beam generator 401, the diffraction device 402, the polygon mirror 701, the condenser lens 404, and the like, as in the first embodiment, the lead electrode (first terminal) 90 and the terminal (second terminal) Terminal) 1111 can be suitably bonded.

  Further, if one joint structure 405 is formed for each side mirror 703 by adjusting the rotation speed of the prism body 702 and the replacement timing of the joint structure 405 by the control device, a plurality of polygon mirrors 701 are provided. Thus, the continuous bonding process (formation of a plurality of bonding structures 405) of the laminated structure 406 can be suitably performed, and the efficiency of the bonding process can be improved.

  Further, a bonding method, a bonding structure, a bonding apparatus, a droplet discharge head manufacturing method, and a droplet discharge head according to a third embodiment of the present invention will be described. Below, it demonstrates centering around difference with the said embodiment, and abbreviate | omits the description about the same matter. In the present embodiment, instead of the diffracting means, a refracting means having a function of refracting incident laser light is used, and a point that does not require a condenser lens is different from the first embodiment. The configuration of the refracting means will be described.

FIG. 8 is a diagram illustrating a schematic configuration of the bonding apparatus according to the present embodiment.
In FIG. 8, a bonding apparatus 800 includes a laser light generating apparatus 401 that irradiates laser light, a refraction apparatus (refracting means) 801 that is arranged so that the laser light is incident substantially perpendicularly, and the refraction apparatus 801 is refracted. And a galvanometer mirror 403 that reflects the laser beam that is directed toward the bonding structure 405.

  The refracting device 801 includes, for example, a plurality of cylindrical lenses arranged in parallel with each other along the vertical direction with respect to the emitted laser light, and the laser light incident from the laser light generating device 401 is transmitted to each cylinder. Laser light (refracted laser light) refracted by the lens and exhibiting a predetermined intensity distribution having a plurality of beam spots (condensing points) is irradiated from the surface (exiting surface) opposite to the incident surface.

  A cylindrical lens is usually a lens that is a transparent body surrounded by two cylindrical surfaces or a cylindrical surface and a plane, and has a function of converging a light beam in a specific direction among light beams transmitted through the transparent body. The direction parallel to the cylindrical axis of the cylindrical lens is called the axis (Axis) of the lens. Usually, there is no degree in the direction parallel to the axis, and the strongest degree is given in the direction perpendicular to the axis. Therefore, the light beam entering the axial direction is not refracted, but is refracted when entering the other direction, and the light beam entering the direction perpendicular to the axis is refracted most strongly, but the light beam is refracted only in a certain direction. The light beam forms an image in a linear shape instead of a single point. However, in the cylindrical lens according to the present embodiment, since the degree of weakness is also given in the direction parallel to the axis, the light beam entering the axial direction is also refracted, and as a result, the cross section of the light beam has an elliptical shape.

In the refracting device 801, a plurality of cylindrical lenses are arranged at appropriate intervals, and a plurality of laser light beam spots (condensing points) are formed by the plurality of cylindrical lenses, whereby the refracting device 801 has a predetermined intensity. Laser light (refracted laser light) exhibiting a distribution is irradiated toward the galvanometer mirror 403.
The galvanometer mirror 403 reflects the laser beam having a predetermined intensity distribution irradiated from the refracting device 801 and irradiates the junction structure 405. The irradiated laser beam is refracted so as to form a beam spot by the cylindrical lens. Therefore, the condensing lens 404 is unnecessary. Thereby, the structure of the joining apparatus 800 can be simplified and the manufacturing cost of the joining apparatus 800 can be reduced.

With the configuration described above, in the bonding apparatus 800, the laser light generating apparatus 401, the refracting apparatus 801, and the galvanometer mirror 403 cooperate to scan a region where a bonded portion is to be formed with laser light having a predetermined intensity distribution.
Further, the refracting means of the present embodiment is not limited to the refracting device 801 including the plurality of cylindrical lenses described above, and may be a refracting device including a plurality of spherical lenses or aspherical lenses instead of the plurality of cylindrical lenses. Also by these, laser light (refracted laser light) exhibiting a predetermined intensity distribution having a plurality of beam spots (condensing points) can be irradiated.

In addition, an optical system may be formed by appropriately combining a plurality of types of refractive lenses such as a cylindrical lens, a spherical lens, and an aspherical lens in a refracting device, thereby making the shape of a beam spot (condensing point) easy. It can be set to any shape.
In addition, the ink jet recording head (droplet discharge head) of each of the embodiments described above constitutes a part of a recording head unit including an ink flow path communicating with an ink cartridge or the like, and forms an ink jet recording apparatus (droplet). Mounted on the discharge device). Hereinafter, an example of an ink jet recording apparatus as a droplet discharge apparatus of the present invention will be described.

FIG. 9 is a schematic view showing an example of the ink jet recording apparatus (droplet discharge apparatus).
An ink jet recording apparatus (droplet discharge apparatus) 2000 includes recording head units 1A and 1B having the above-described ink jet recording head (droplet discharge head) 1000.
As shown in FIG. 9, the recording head units 1A and 1B having the ink jet recording head 1000 are detachably provided with cartridges 2A and 2B constituting ink supply means, and the recording head units 1A and 1B are mounted. The carriage 3 is provided on a carriage shaft 5 attached to the apparatus main body 4 so as to be movable in the axial direction. For example, the recording head units 1A and 1B eject a black ink composition and a color ink composition, respectively.

  Then, the driving force of the driving motor 6 is transmitted to the carriage 3 through a plurality of gears and a timing belt 7 (not shown), so that the carriage 3 on which the recording head units 1A and 1B are mounted is moved along the carriage shaft 5. The On the other hand, the apparatus body 4 is provided with a platen 8 along the carriage shaft 5, and a recording sheet S, which is a recording medium such as paper fed by a paper feed roller (not shown), is conveyed on the platen 8. It is like that.

The bonding method, bonding structure, bonding apparatus, droplet discharge head manufacturing method, droplet discharge head, and droplet discharge apparatus according to the present invention have been described based on the illustrated embodiments, but the present invention is not limited thereto. Is not to be done.
For example, the structure of an ink jet recording head (droplet discharge head) to which the present invention is applied is not limited to the above-described structure, and as shown in FIG. 10, for driving a piezoelectric element 300 on a reservoir forming substrate 30, For example, a drive circuit 150 such as a circuit board or a semiconductor integrated circuit (IC) is mounted, and the drive circuit 150 and a lead electrode 90 drawn from each piezoelectric element 300 are extended by, for example, wire bonding or the like. The structure connected via 151 may be sufficient. In the configuration shown in FIG. 10, a connection wiring 152 for supplying a signal to the drive circuit 150 extends from the vicinity of the drive circuit 150 to the vicinity of the end of the reservoir formation substrate 30 on the reservoir formation substrate 30 to be connected. The wiring 152 is connected to the drive circuit 150 via a wiring 153 extended by wire bonding or the like.

  In this structure, the external wiring cable 110 is connected to the end portion of the connection wiring 152 through the connection metal 120 in the same manner as the ink jet recording head 1000 described above. That is, here, the end portion of the connection wiring 152 connected to the terminal of the drive circuit 150 serves as a connection terminal (first terminal) of the wiring for driving the piezoelectric element 300. Such connection between the end of the connection wiring 152 and the external wiring cable 110 can also be reliably connected to each other by applying the present invention.

  As described above, the drive circuit 150 is mounted on the reservoir forming substrate 30 and the connection wiring 152 and the external wiring cable 110 are bonded on the reservoir forming substrate 30. The external wiring cable 110 can be satisfactorily connected to the connection wiring 152 while preventing the formation substrate 10 from being deformed or cracked.

The installation location of the drive circuit 150 and the connection location with the external wiring cable 110 are not particularly limited. For example, the drive circuit 150 is provided on the flow path formation substrate 10 and the drive circuit 150 is provided on the flow path formation substrate 10. Connection wiring connected to the terminals may be provided, and the connection wiring and the external wiring cable 110 may be connected on the flow path forming substrate 10.
Furthermore, without using the lead wire 90, for example, the piezoelectric layer 70 and the upper electrode film 80 of the piezoelectric element 300 are extended to the outside of the piezoelectric element holding portion 32, and an external wiring cable is connected to the extended upper electrode film 80. 110 may be directly connected.

In the first embodiment described above, a piezo-type and 2-axis control type galvanometer is used. However, for example, a motor-driven type and a single-axis control type may be used as the galvanometer. . Even if such a galvanometer is used, the same effect as described above can be obtained.
In the above-described embodiment, the lead electrode (first terminal) 90 and the terminal (second terminal) 1111 are described as being joined via the connection metal 120, but the connection metal is interposed. Alternatively, the lead electrode (first terminal) 90 and the terminal (second terminal) 1111 may be directly joined. Further, an anisotropic conductive adhesive (ACF) or the like may be used instead of the connection metal.

  In the above-described embodiment, the biconvex lens is used as the condenser lens 404. However, the type of the condenser lens 404 is not particularly limited. For example, as the condenser lens 404, a plano-convex lens or the like may be used. Further, the lens is not limited to having the light collecting function as described above, and may have any function. A lens group composed of a plurality of lenses may be applied. Moreover, the lens part as described above may not be provided.

In the above-described embodiment, the laser beam is scanned by the reflection unit. However, the reflection unit as described above is not necessarily used as long as the laser beam can be scanned.
Further, in the above-described embodiment, the configuration in which the diffracting unit and the reflecting unit are used in combination and the configuration in which the refracting unit and the reflecting unit are used in combination have been described. For example, the diffracting unit, the reflecting unit, and the refracting unit are combined. It may be used. Further, the arrangement of the diffraction means, the reflection means, the refraction means, and the like on the optical path of the laser light emitted from the laser light generator is not limited to that described above. For example, the diffracting means and the refracting means may be arranged on the optical path of the laser light reflected by the reflecting means.

The present invention is not limited to the thin film type ink jet recording head manufactured by the film formation and lithography method as described above, but also a thick film type ink jet type formed by a method such as attaching a green sheet. It can also be applied to a recording head.
Furthermore, the present invention is not limited to the ink jet recording head (droplet discharge head) and the ink jet recording apparatus (droplet discharge apparatus) as described above, and can be applied to various semiconductor mounting and the like. Alternatively, the present invention can be applied to an organic EL element (electroluminescence) display device whose display is controlled by voltage, a TFD (Thin Film Diode) liquid crystal display device, a PDP (Plasma Display Panel), or the like.

For example, in a TFD liquid crystal display device, a scanning line and a data line provided on each of the opposing surfaces of the TFD substrate and the opposing substrate disposed opposite to each other with a liquid crystal layer enclosing a TN (Twist Nematic) type liquid crystal interposed therebetween. The present invention may be applied to the joining of the electrode part formed by converging the electrode and the flexible connector, and in the PDP, the front surface disposed opposite to the cell structure enclosing xenon (Xe) or the like The bonding method of the present invention is used for bonding electrode portions formed by converging wires connected to conductive electrodes and address electrodes made of ITO or the like disposed on opposite surfaces of glass and rear glass and external wires. A bonding structure and a bonding apparatus may be applied.
Moreover, in embodiment mentioned above, although the member provided with the 1st terminal group was demonstrated as what is a member different from the member provided with the 2nd terminal group, the 1st terminal group and the 2nd terminal group are It may be provided on the same member.

1 is an exploded perspective view showing an ink jet recording head (droplet discharge head) to which the present invention is applied. FIG. 2 is a plan view showing the ink jet recording head of FIG. 1. FIG. 3 is a cross-sectional view of the pressure generation chamber in the ink jet recording head of FIG. 1, FIG. 3A is a cross-sectional view in the longitudinal direction of the pressure generation chamber, and FIG. 3B is a line A- in FIG. It is sectional drawing which follows A '. It is a figure showing a schematic structure of a joining device and joining structure concerning a 1st embodiment of the present invention. It is a figure which shows the scanning pattern of the laser beam (reflection laser beam) irradiated to the several laminated structure in which the joining apparatus which concerns on 1st Embodiment of this invention was arranged in parallel, Fig.5 (a) is the predetermined irradiated FIG. 5B is a diagram showing a change in the intensity of the laser beam in the scan (a change with time in the intensity of the laser beam accompanying the scan), and FIG. ) Is a diagram showing the distribution of the amount of thermal energy given to the laminated structure (terminal group) by scanning with laser light. It is process sectional drawing which shows the joining method which concerns on 1st Embodiment of this invention, and the manufacturing method of a droplet discharge head. It is a figure which shows schematic structure of the joining apparatus which concerns on 2nd Embodiment of this invention. It is a figure which shows schematic structure of the joining apparatus which concerns on 3rd Embodiment of this invention. 1 is a schematic diagram illustrating an example of an ink jet recording apparatus (droplet discharge apparatus) to which the present invention is applied. FIG. 10 is a view showing another ink jet recording head (droplet discharge head) to which the present invention is applied, FIG. 10A is a plan view, and FIG. 10B is a cross-sectional view.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1A, 1B ... Head unit 2A, 2B ... Cartridge 3 ... Carriage 4 ... Apparatus main body 5 ... Carriage shaft 6 ... Drive motor 7 ... Timing belt 8 ... Platen 10 ... Flow path formation board 11 ... Partition 12 ... Pressure generating chamber 13 ... Communication Part 14: Ink supply path 20 ... Nozzle plate 21 ... Nozzle opening 25 ... Flexible part 30 ... Reservoir forming substrate 31 ... Reservoir part 32 ... Piezoelectric element holding part 36 ... Ink introduction path 40 ... Compliance substrate 41 ... Sealing film 42 ... Fixing plate 44 ... Ink introduction port 50 ... Elastic film 60 ... Lower electrode film 70 ... Piezoelectric layer 80 ... Upper electrode film 90 ... Lead electrode (first terminal) 100 ... Reservoir 110 ... External wiring cable 111 ... External wiring 1111 ... Terminal (second terminal) 112... Coating film 113... Terminal group (second terminal group) 12 DESCRIPTION OF SYMBOLS 0 ... Metal for connection 130 ... Pressing plate 150 ... Drive circuit 151 ... Wiring 152 ... Connection wiring 153 ... Wiring 300 ... Piezoelectric element 310 ... Electrode part (1st terminal group) 400, 700, 800 ... Joining device 401 ... Laser beam Generating device (laser beam emitting means) 402 ... Diffraction device (diffracting means) 403 ... Galvano mirror (reflecting means, scanning means) 404 ... Condensing lens 405 ... Junction structure 406 ... Laminated structure 407 ... Scanning mirror (reflector) 701 ... Polygon mirror (reflecting means, scanning means) 702 ... prism body 703 ... side mirror (reflector) 801 ... refracting means (refracting apparatus) 1000 ... ink jet recording head (droplet discharge head) 2000 ... ink jet recording apparatus (droplet) Discharge device) S ... Recording sheet

Claims (29)

A first terminal group having a plurality of first terminals arranged in parallel to each other, and a second terminal group having a plurality of second terminals arranged corresponding to each of the first terminals A joining method for joining
It is a method of joining the first terminal group and the second terminal group by scanning a laser beam at least along the arrangement direction of the terminals,
The laser light exhibits a predetermined intensity distribution along the scanning direction, and the length of the predetermined intensity distribution in the scanning direction is at least equal to or less than the length in the arrangement direction of the terminal group,
The energy distribution of the laser beam given by the scanning is non-uniform at each part in the arrangement direction,
The plurality of first terminals and the plurality of second terminals corresponding to the plurality of first terminals are electrically connected to each other by the laser light. Joining method characterized by joining.   The joining method according to claim 1, wherein the predetermined intensity distribution is asymmetric with respect to the scanning direction.   The bonding method according to claim 1, wherein the laser beam is reflected by a reflecting unit having a function of changing the reflection direction of the incident laser beam with time.   The joining method according to claim 3, wherein the reflecting means changes a reflection direction of the laser light by rotating or rotating a reflector that reflects the laser light.   The joining method according to claim 3 or 4, wherein the reflecting means is a galvanometer mirror.   The joining method according to claim 3, wherein the reflecting means is a polygon mirror.   The bonding method according to claim 1, wherein the laser beam is diffracted in a desired direction by a diffraction unit having a function of diffracting the incident laser beam.   The bonding method according to claim 1, wherein the laser beam is refracted in a desired direction by a refracting unit having a function of refracting the incident laser beam.   The bonding method according to claim 1, wherein the intensity of the laser light incident on the reflecting means is changed over time.   The bonding method according to claim 1, wherein the irradiation time of the laser beam irradiation site is controlled to be different at each site in the scanning direction.   The intensity of the laser beam applied to the portion corresponding to the first terminal arranged near the end of the first terminal group in the arrangement direction is the center of the first terminal group in the arrangement direction. The bonding method according to claim 1, wherein the intensity of the laser beam applied to a portion corresponding to the first terminal disposed in the vicinity of the portion is larger than the intensity of the laser beam.   The bonding method according to claim 1, wherein the laser light has a distribution in which irradiation intensity continuously changes in the scanning direction.   The bonding method according to claim 1, wherein the laser beam is a semiconductor laser.   The junction according to any one of claims 1 to 13, wherein the temperature of the first terminal group and / or the second terminal group is measured, and the intensity of the laser beam is controlled according to the measured temperature. Method.   The bonding method according to claim 1, wherein the laser beam has a wavelength of 800 to 900 nm.   The bonding method according to claim 1, wherein the laser light is irradiated with a brazing material disposed between the first terminal and the second terminal.   The temperature of the first terminal group and the second terminal group when the laser beam is irradiated when the melting point of the brazing material is T [° C.] is (T + 50) ° C. or less. The joining method described in 1.   The joining method according to claim 1, wherein the first terminal and the second terminal are directly joined without using a brazing material.   The joining method according to claim 1, wherein in the first terminal group, the plurality of first terminals are arranged at substantially equal intervals.   A joining structure in which the first terminal group and the second terminal group are joined by the joining method according to claim 1. A first terminal group having a plurality of first terminals arranged in parallel to each other, and a second terminal group having a plurality of second terminals arranged corresponding to each of the first terminals A joining device for joining
Laser light emitting means for emitting laser light;
Scanning means for scanning at least the terminal group along the arrangement direction of the terminals with the laser light emitted from the laser light emitting means;
The laser light exhibits a predetermined intensity distribution along the scanning direction, and the length of the predetermined intensity distribution in the scanning direction is at least equal to or less than the length in the arrangement direction of the terminal group,
The energy distribution of the laser beam given by the scanning is non-uniform at each part in the arrangement direction,
The plurality of first terminals and the plurality of second terminals corresponding to the plurality of first terminals are electrically connected to each other by the laser light. A joining apparatus characterized by joining. A lens part on the optical path of the laser beam;
The joining apparatus according to claim 21, wherein the first terminal group and the second terminal group are joined by the laser light emitted from the lens unit.   The joining apparatus according to claim 21 or 22, wherein the scanning means is a galvanometer mirror.   The joining apparatus according to claim 21, wherein the scanning unit is a polygon mirror.   The bonding apparatus according to any one of claims 21 to 24, further comprising irradiation intensity varying means for changing the intensity of the laser light with time.   A method for manufacturing a droplet discharge head, wherein the droplet discharge head is manufactured using the bonding method according to claim 1.   26. A method of manufacturing a droplet discharge head, wherein a droplet discharge device is manufactured using the bonding apparatus according to claim 21.   A droplet discharge head manufactured using the manufacturing method according to claim 26 or 27.   A droplet discharge device comprising the droplet discharge head according to claim 28.

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