JP4687450B2 - Flexible substrate mounting method, droplet discharge head manufacturing method, droplet discharge head, and droplet discharge apparatus - Google Patents

Description

The present invention is implementation of a flexible substrate, a method of manufacturing a droplet discharge head, a droplet discharge head, and a droplet discharge device.

  As one method for manufacturing a microdevice, a droplet discharge method (inkjet method) has been proposed. This droplet discharge method is a method in which a functional liquid containing a material for forming a device is formed into droplets and discharged from a droplet discharge head. Patent Document 1 below discloses an example of a technique related to a droplet discharge head (inkjet recording head). In the droplet discharge head disclosed in Patent Document 1, a drive element (piezoelectric element) provided on the lower side of the stepped portion is wire-bonded to a drive device (driver IC) provided on the upper side of the stepped portion. It is a structure connected by.

By the way, when manufacturing a microdevice based on the droplet discharge method, in order to meet the demand for further miniaturization of the microdevice, the distance between the nozzle openings provided in the droplet discharge head (nozzle pitch) Is desired to be as small (narrow) as possible. However, since a plurality of the driving elements are provided corresponding to the nozzle openings, when the nozzle pitch is reduced, the distance between the driving elements is also reduced (shortened) corresponding to the nozzle pitch.
JP 2000-296616 A

  However, if the distance between the drive elements is reduced (shortened), it is very difficult to connect each of the plurality of drive elements and the driver IC by wire bonding because a short circuit easily occurs between the wires. Workability will be significantly impaired. That is, in the current structure, for example, the pitch between the wires (wiring pitch) is 64 μm, but wire bonding mounting at such a pitch has a problem that the strength of the connection portion is weak and the yield does not increase. In addition, when the pitch between terminals is further narrowed, there is a problem that it is almost impossible to cope with wi bonding.

  Therefore, in order to eliminate the problems caused by the wire bonding connection, a short circuit is achieved by using an outer lead bonding connection using a flexible substrate (flexible substrate) in which a wiring pattern that functions as an outer lead is formed in advance. It is conceivable to make an electrical connection between the drive element (piezoelectric element) and the drive device (driver IC) without causing such inconveniences.

However, when such a flexible substrate is used, since the connection area of the flexible substrate itself to the droplet discharge head is small, it is difficult to obtain sufficient connection strength, and thus sufficient connection strength can be obtained. A technique is required.
In addition, as a method for performing adhesion and electrical connection at the same time, an anisotropic conductive material is generally used. For example, an anisotropic conductive film (ACF) has a high curing temperature of about 150 ° C. For this reason, there is a risk of destroying the drive element when it is cured.

  Further, in order to connect the driving element provided on the lower stage side of the stepped portion and the driving device provided on the upper stage side of the stepped portion, it is necessary to raise the flexible substrate from the lower stage side to the upper stage side. In order to obtain sufficient connection strength as described above, it is desirable that the rising portion is also fixed to the lower surface using, for example, an anisotropic conductive material. However, for example, when the rising portion is fixed to the lower surface using an anisotropic conductive material, the conductive particles contained in the anisotropic conductive material in the fixed portion do not contribute to electrical connection, Moisture and electrolysis cause migration and cause a short circuit between terminals.

  Further, when connecting the flexible substrate to the lower surface, for example, an anisotropic conductive paste before curing is attached to the connection portion of the flexible substrate in advance as an anisotropic conductive material, and this anisotropic conductive paste is in that state. It is conceivable to bond the connecting portion to the lower surface through the gap. However, in that case, the amount of the anisotropic conductive paste adhered to the connection portion of the flexible substrate varies, and this makes it difficult to obtain sufficient connection strength to the lower surface of the flexible substrate. . That is, in order to attach the anisotropic conductive paste to the connection portion of the flexible substrate, the anisotropic conductive paste before curing is arranged in advance on the transfer stage, the flexible substrate is brought into contact with the anisotropic conductive paste, This is because the anisotropic conductive paste is transferred to the flexible substrate by pulling up, but at this time, the entire amount disposed on the transfer stage is not necessarily transferred to the flexible substrate side.

  Furthermore, when the flexible substrate is brought into contact with the anisotropic conductive paste on the transfer stage, and the film is pulled up and transferred, the thermosetting resin in the anisotropic conductive paste pulls the yarn, and the transferred anisotropic material Bubbles may be mixed in the conductive paste. That is, normally, the flexible substrate is lifted by raising it straight up.However, when the flexible substrate is lifted in this way, the yarn becomes large when the yarn is pulled away from the transfer stage and transferred to the flexible substrate. By falling from the pulled state, air is trapped in the part where the thread has fallen and remains as fine bubbles. When the flexible substrate is finally mounted, bubbles remain in the anisotropic conductive paste used for bonding. Then, moisture permeates through the air bubbles, which may cause a decrease in adhesive strength and peeling of the flexible substrate.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to arrange a flexible substrate from the upper side to the lower side of the stepped portion and mount the flexible substrate between the upper side and the lower side. As a technique, it is to provide a technique capable of obtaining a sufficient connection strength particularly for the flexible substrate to be mounted and the lower side of the step portion.

In order to achieve the above object, a flexible substrate mounting method according to the present invention includes arranging a flexible substrate having a conductive portion from an upper stage side to a lower stage side of a stepped portion, and the conductive portion between the upper stage side and the lower stage side. A method for mounting a flexible substrate that is electrically conducted by
Adhering one end of the lower surface of the flexible substrate having the conductive portion to the lower surface of the step using an anisotropic conductive paste containing conductive particles in a thermosetting resin, Conducting the conductive portion of the flexible substrate and the terminal portion provided on the lower surface,
The thermosetting resin that is the same as the thermosetting resin in the anisotropic conductive paste at the vicinity of the one end side of the rising portion that rises along the step of the stepped portion from the one end side of the lower surface of the flexible substrate A step of adhering to the lower side surface of the stepped portion by,
The step of adhering one end side of the lower surface of the flexible substrate to the lower surface of the stepped portion is performed by applying one end side of the lower surface of the flexible substrate to the anisotropic conductive paste before curing disposed on the transfer stage in advance. And transferring the anisotropic conductive paste to the one end side, and then transferring the one end side of the flexible substrate to which the anisotropic conductive paste is transferred to the one end side. And a step of joining to the lower surface of the stepped portion via,
As the transfer stage, a surface on which a paste disposition region for disposing the anisotropic conductive paste is formed and a large number of recesses are formed in the entire region is used .
According to the flexible substrate mounting method of the present invention, a flexible substrate having a conductive portion is disposed from the upper side to the lower side of the stepped portion, and the upper portion and the lower step are electrically connected by the conductive portion. A flexible substrate mounting method,
Adhering one end of the lower surface of the flexible substrate having the conductive portion to the lower surface of the step using an anisotropic conductive paste containing conductive particles in a thermosetting resin, Conducting the conductive portion of the flexible substrate and the terminal portion provided on the lower surface,
The thermosetting resin that is the same as the thermosetting resin in the anisotropic conductive paste at the vicinity of the one end side of the rising portion that rises along the step of the stepped portion from the one end side of the lower surface of the flexible substrate And a step of fixing to the lower surface of the step portion.

According to this flexible substrate mounting method, one end of the lower surface of the flexible substrate is bonded to the lower surface using an anisotropic conductive paste, and the rising portion of the lower surface of the flexible substrate is near the one end. Since the portion is fixed to the lower surface of the step portion by the thermosetting resin, a sufficiently high connection strength can be obtained for the connection between the flexible substrate and the lower step side of the step portion.
Further, since the fixing at the rising portion is performed by the same thermosetting resin as the thermosetting resin in the anisotropic conductive paste, the conductive particles are hardly present at the rising portion. Therefore, migration due to the conductive particles present at the rising portion is suppressed, and a short circuit between the terminals is prevented.
Furthermore, since the thermosetting resin used for fixing at the rising portion is the same as the thermosetting resin in the anisotropic conductive paste, the bonding at the one end side of the lower surface of the flexible substrate and the fixing at the rising portion. Each part consists of the hardened | cured material of the same thermosetting resin. Therefore, the bonded portion and the fixed portion exhibit the same thermal behavior, and peeling of the flexible substrate due to a difference in thermal expansion coefficient is prevented.

  In the flexible substrate mounting method, the step of adhering one end of the lower surface of the flexible substrate to the lower surface of the stepped portion includes the anisotropic conductive material before curing disposed on the transfer stage in advance. One end of the lower surface of the flexible substrate is brought into contact with the paste, and then pulled up to transfer the anisotropic conductive paste to the one end, and one end of the flexible substrate to which the anisotropic conductive paste has been transferred And a step of joining the anisotropic conductive paste to the lower surface of the stepped portion via the transferred anisotropic conductive paste, and the anisotropic conductive paste is disposed as the transfer stage. It is preferable to use a surface on which a large number of recesses are formed on the entire surface.

  In this way, when one end of the lower surface of the flexible substrate is brought into contact with the anisotropic conductive paste of the transfer stage and then lifted to transfer the anisotropic conductive paste, a paste placement region of the transfer stage is formed. Since a large number of recesses are formed on the entire surface of the surface, the anisotropic conductive paste of the transfer stage easily peels from the surface on which the paste placement region is formed. The entire amount is transferred to the flexible substrate. Therefore, the problem that the connection strength with respect to the lower surface of the flexible substrate becomes sufficient due to the variation in the amount of the anisotropic conductive paste transferred to the flexible substrate is prevented.

Further, in the flexible substrate mounting method, a concave paste containing portion for containing the anisotropic conductive paste is formed on the transfer stage, and a bottom surface of the paste containing portion forms the paste arrangement region. And one side of the bottom surface is an inclined surface inclined toward the opening of the paste containing portion,
In the step of transferring the anisotropic conductive paste to one end of the flexible substrate, one end of the lower surface of the flexible substrate is brought into contact with the anisotropic conductive paste and then pulled up, It is preferable to pull up obliquely toward the one side along the surface direction of the inclined surface.

  In this way, the anisotropic conductive paste transferred to the flexible substrate at the time of pulling is pulled largely by the flexible substrate being pulled up diagonally, although the thermosetting resin pulls the yarn. It is relatively small and can be drawn diagonally. Therefore, when pulled up, the pulled yarn immediately falls to the transferred anisotropic conductive paste side. Therefore, almost no air is caught in the thread that has fallen immediately in such a small pulled state, so that air bubbles remain in the anisotropic conductive paste, resulting in a decrease in adhesive force, and the flexible substrate after mounting. Inconveniences such as peeling are prevented.

In the flexible substrate mounting structure of the present invention, the flexible substrate having the conductive portion is arranged from the upper side to the lower side of the stepped portion, and the upper portion and the lower step side are electrically connected by the conductive portion. A flexible substrate mounting structure made conductive,
One end side of the lower surface having the conductive portion of the flexible substrate is bonded to the lower surface of the step portion through an anisotropic conductive paste containing conductive particles in a thermosetting resin, thereby The conductive portion of the flexible substrate and the terminal portion provided on the lower surface are made conductive,
The thermosetting resin in the vicinity of the one end side of the rising portion rising from the one end side along the step of the step portion on the lower surface of the flexible substrate is the same as the thermosetting resin in the anisotropic conductive paste. Is fixed to the lower surface of the step portion.

According to this flexible substrate mounting structure, one end of the lower surface of the flexible substrate is bonded to the lower surface by the anisotropic conductive paste, and the rising portion of the lower surface of the flexible substrate near the one end is heated. Since it is fixed to the lower surface of the step portion by the curable resin, a sufficiently high connection strength can be obtained for the connection between the flexible substrate and the lower step side of the step portion.
Further, since the fixing at the rising portion is made of the same thermosetting resin as the thermosetting resin in the anisotropic conductive paste, almost no conductive particles are present at the rising portion. Therefore, migration due to the conductive particles present at the rising portion is suppressed, and a short circuit between the terminals is prevented.
Furthermore, since the thermosetting resin used for fixing at the rising portion is the same as the thermosetting resin in the anisotropic conductive paste, the adhesive portion and the rising portion at one end of the lower surface of the flexible substrate are used. These fixed portions are made of a cured product of the same thermosetting resin. Therefore, the bonded portion and the fixed portion exhibit the same thermal behavior, and peeling of the flexible substrate due to a difference in thermal expansion coefficient is prevented.

The method for manufacturing a droplet discharge head according to the present invention includes a drive circuit unit provided on the upper side of the stepped portion, a drive element provided on the lower side of the stepped portion and driven by the drive circuit unit, and the drive And a flexible substrate having a conductive portion that electrically connects the circuit portion and the driving element, wherein the flexible substrate is mounted by the flexible substrate mounting method. It is a feature.
The droplet discharge head of the present invention includes a drive circuit unit provided on the upper side of the stepped portion, a drive element provided on the lower side of the stepped portion and driven by the drive circuit unit, and the drive circuit In a droplet discharge head including a flexible substrate having a conductive portion that electrically connects a portion and the driving element, the flexible substrate is mounted by the mounting method described above.

  According to the manufacturing method of the droplet discharge head and the droplet discharge head, sufficiently high connection strength can be obtained as described above for the connection between the flexible substrate and the lower side of the step portion, and the rising portion Migration caused by the conductive particles present in the substrate is suppressed to prevent a short circuit between terminals, and further, peeling of the flexible substrate due to a difference in thermal expansion coefficient is prevented.

A droplet discharge apparatus according to the present invention includes the droplet discharge head described above.
According to this droplet discharge device, sufficiently high connection strength can be obtained as described above for the connection between the flexible substrate and the lower side of the step portion, and migration caused by the conductive particles present in the rising portion The liquid droplet ejection device itself is also provided with a flexible substrate since the short circuit between the terminals is prevented and the flexible substrate is prevented from being peeled off due to a difference in thermal expansion coefficient. Therefore, it is possible to prevent a connection failure or the like from occurring.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, an XYZ orthogonal coordinate system is set, and the positional relationship of each member will be described with reference to this XYZ orthogonal coordinate system. The predetermined direction in the horizontal plane is the X-axis direction, the direction orthogonal to the X-axis direction in the horizontal plane is the Y-axis direction, and the direction orthogonal to each of the X-axis direction and the Y-axis direction (that is, the vertical direction) is the Z-axis direction. To do.

<Droplet ejection head>
First, an embodiment in which the flexible substrate mounting structure of the present invention is applied to a droplet discharge head will be described with reference to FIGS. 1 is an external perspective view showing an embodiment of a droplet discharge head, FIG. 2 is a partially broken view of the perspective view of the droplet discharge head as viewed from below, and FIG. 3 is a view taken along line AA in FIG. Sectional drawing and FIG. 4 are the figures which looked at the flexible substrate from the lower surface side.
As shown in FIG. 3, the droplet discharge head 1 includes a driver IC (driving circuit unit) 200, a piezoelectric element (driving element) 300 driven by the driver IC 200, and a substrate formed with a stepped portion 250. Provided and configured to eject droplets of functional liquid.

  The liquid droplet ejection head 1 includes a nozzle substrate 16 having a nozzle opening 15 through which liquid droplets are ejected, and a flow path forming substrate 10 that is connected to the upper surface of the nozzle substrate 16 and forms a flow path through which liquid droplets flow. The diaphragm 400 connected to the upper surface of the flow path forming substrate 10 and displaced by driving the piezoelectric element (driving element) 300, and the reservoir forming substrate 20 connected to the upper surface of the diaphragm 400 and forming the reservoir 100 A flexible flexible substrate 500 provided on the upper surface side of the reservoir forming substrate 20; a driver IC (device) 200 for driving the piezoelectric element 300 provided on the lower surface 500A of the flexible substrate 500; A wiring pattern (conductive portion) 510 that is provided on the lower surface 500A of 500 and electrically connects the driver IC 200 and the piezoelectric element 300; Those configured with a. In the present embodiment, the step portion 250 is formed by the flow path forming substrate 10 and the reservoir forming substrate 20 or the like disposed thereon.

The operation of the droplet discharge head 1 is controlled by an external controller CT (see FIG. 1).
The pressure generation chamber 12 in which the functional liquid before being discharged from the nozzle opening 15 is disposed is formed by a space surrounded by the flow path forming substrate 10, the nozzle substrate 16, and the vibration plate 400. . A reservoir 100 that preliminarily holds the functional liquid before being supplied to the pressure generating chamber 12 is formed by a space surrounded by the reservoir forming substrate 20 and the flow path forming substrate 10.

  The lower surface side of the flow path forming substrate 10 is open, and the nozzle substrate 16 is adhered to the lower surface of the flow path forming substrate 10 so as to cover the opening. The lower surface of the flow path forming substrate 10 and the nozzle substrate 16 are fixed to each other through, for example, an adhesive or a heat welding film. As shown in FIG. 2, a plurality of nozzle openings 15 for discharging droplets are formed in the nozzle substrate 16 in an aligned state. That is, a plurality of nozzle openings 15 are arranged in the Y-axis direction on the nozzle substrate 16, whereby the first nozzle opening group 15 </ b> A, the second nozzle opening group 15 </ b> B, the third nozzle opening group 15 </ b> C, and the fourth nozzle opening. Groups 15D are formed respectively.

The first nozzle opening group 15A and the second nozzle opening group 15B are arranged to face each other in the X-axis direction. The third nozzle opening group 15C is provided on the + Y side of the first nozzle opening group 15A, and the fourth nozzle opening group 15D is provided on the + Y side of the second nozzle opening group 15B. Therefore, the third nozzle opening group 15C and the fourth nozzle opening group 15D are arranged so as to face each other in the X-axis direction.
In FIG. 2, each of the nozzle opening groups 15 </ b> A to 15 </ b> D is shown to be configured by six nozzle openings 15, but actually, for example, it is configured by about 720 nozzle openings 15. Has been.

  In the flow path forming substrate 10, a plurality of partition walls 11 are formed in the opening. The flow path forming substrate 10 is formed of a silicon single crystal that is a rigid body, and the plurality of partition walls 11 are formed by anisotropic etching of the silicon single crystal substrate that is a base material of the flow path forming substrate 10. ing. A plurality of pressure generating chambers 12 are formed by a space surrounded by the flow path forming substrate 10 having the plurality of partition walls 11, the nozzle substrate 16, and the diaphragm 400. A plurality of pressure generating chambers 12 are formed so as to correspond to the plurality of nozzle openings 15. That is, a plurality of pressure generation chambers 12 are provided side by side in the Y-axis direction so as to correspond to the plurality of nozzle openings 15 constituting each of the first to fourth nozzle opening groups 15A to 15D.

  A plurality of pressure generating chambers 12A corresponding to the first nozzle opening group 15A constitutes a first pressure generating chamber group 12A, and a plurality of pressure generating chambers 12 corresponding to the second nozzle opening group 15B are formed. Constitutes a second pressure generation chamber group 12B, and a plurality of pressure generation chambers 12 corresponding to the third nozzle opening group 15C constitutes a third pressure generation chamber group 12C, corresponding to the fourth nozzle opening group 15D. Thus, a fourth pressure generation chamber group 12D is configured by the plurality of pressure generation chambers 12 formed. The first pressure generation chamber group 12A and the second pressure generation chamber group 12B are arranged to face each other in the X-axis direction, and a partition wall 10K is formed between them. Similarly, a partition wall 10K is also formed between the third pressure generation chamber group 12C and the fourth pressure generation chamber group 12D, and these are arranged to face each other in the X-axis direction.

  Of the plurality of pressure generating chambers 12 forming the first pressure generating chamber group 12A, the end portion on the −X side is closed by the partition wall 10K, but the end portions on the + X side are connected to each other. As shown in FIG. 3, it is connected to the reservoir 100. The reservoir 100 is introduced from the functional liquid inlet 25 and temporarily holds the functional liquid before being supplied to the pressure generation chamber 12, and is formed to extend in the Y axis direction on the reservoir forming substrate 20. The reservoir portion 21 is formed to extend in the Y-axis direction in the flow path forming substrate 10, and is formed to include a communication portion 13 that allows the reservoir portion 21 and each of the pressure generation chambers 12 to communicate with each other. .

  That is, the reservoir 100 is a functional liquid holding chamber (ink chamber) common to the plurality of pressure generating chambers 12 constituting the first pressure generating chamber group 12A. Then, the functional liquid introduced from the functional liquid introduction port 25 flows into the reservoir 100 through the introduction path 26 and passes through the supply path 14 to each of the plurality of pressure generation chambers 12 constituting the first pressure generation chamber group 12A. It comes to be supplied. Note that the pressure generation chambers 12 constituting the second, third, and fourth pressure generation chamber groups 12B, 12C, and 12D also communicate with the reservoir 100 similar to the above.

  The diaphragm 400 disposed between the flow path forming substrate 10 and the reservoir forming substrate 20 is provided on the elastic film 50 so as to cover the upper surface of the flow path forming substrate 10 and on the upper surface of the elastic film 50. The lower electrode film 60 is included. The elastic film 50 is made of, for example, silicon dioxide having a thickness of about 1 to 2 μm, and the lower electrode film 60 is made of, for example, platinum having a thickness of about 0.2 μm. In the present embodiment, the lower electrode film 60 is a common electrode for the plurality of piezoelectric elements 300.

  The piezoelectric element 300 for displacing the diaphragm 400, that is, the driving element in the present invention includes a piezoelectric film 70 provided on the upper surface of the lower electrode film 60 and an upper electrode film provided on the upper surface of the piezoelectric film 70. 80. The piezoelectric film 70 is formed with a thickness of about 1 μm, for example, and the upper electrode film 80 is formed with a thickness of about 0.1 μm, for example. The concept of the piezoelectric element 300 may include the lower electrode film 60 in addition to the piezoelectric film 70 and the upper electrode film 80. That is, the lower electrode film 60 in the present embodiment has both the function as the piezoelectric element 300 and the function as the diaphragm 400. In this embodiment, the elastic film 50 and the lower electrode film 60 function as the diaphragm 400. However, the elastic film 50 may be omitted, and the lower electrode film 60 may also serve as the elastic film (50). .

The piezoelectric element 300 is formed such that the upper electrode film 80 extends to the lower surface (lower surface) of the step portion 250 formed on the reservoir forming substrate 20, and is exposed on the lower surface. This portion is the terminal portion 81 of the present invention. The step portions 250 are respectively formed on both sides of a concave groove 700 formed in the reservoir forming substrate 20 described later. Therefore, the lower step surface of the stepped portion 250 coincides with the bottom surface of the concave groove 700.
In addition, a plurality of piezoelectric elements 300 are provided so as to correspond to the plurality of nozzle openings 15 and the pressure generation chambers 12, respectively. That is, the piezoelectric element 300 including the piezoelectric film 70 and the upper electrode film 80 is provided for each nozzle opening 15 (for each pressure generation chamber 12). As described above, the lower electrode film 60 functions as a common electrode for the plurality of piezoelectric elements 300, and the upper electrode film 80 functions as an individual electrode for the plurality of piezoelectric elements 300.

  A plurality of these piezoelectric elements 300 are juxtaposed in the Y-axis direction in correspondence with each of the nozzle openings 15 constituting the first nozzle opening group 15A, whereby the first piezoelectric element group 300A is formed. It is configured. Similarly, a part thereof is arranged in parallel in the Y-axis direction corresponding to each of the nozzle openings 15 constituting the second nozzle opening group 15B, thereby forming the second piezoelectric element group 300B. The first piezoelectric element group 300A and the second piezoelectric element group 300B are disposed so as to face each other in the X-axis direction. Further, third and fourth piezoelectric element groups (not shown) are configured so as to correspond to the nozzle openings 15 constituting the third and fourth nozzle opening groups 15C and 15D, respectively. The fourth piezoelectric element groups are arranged so as to face each other in the X-axis direction.

  A compliance substrate 30 having a sealing film 31 and a fixing plate 32 is bonded to the reservoir forming substrate 20. The sealing film 31 is made of a material having low rigidity and flexibility (for example, a polyphenylene sulfide film having a thickness of about 6 μm), and the upper part of the reservoir portion 21 is sealed by the sealing film 31. The fixing plate 32 is made of a hard material such as metal (for example, stainless steel having a thickness of about 30 μm). A region of the fixed plate 32 corresponding to the reservoir 100 is an opening 33 that is completely removed in the thickness direction. Under such a configuration, the upper portion of the reservoir 100 is sealed only by the flexible sealing film 31. Therefore, the flexible portion 22 that can be deformed by a change in internal pressure and It has become.

A functional liquid inlet 25 for supplying the functional liquid to the reservoir 100 is formed on the compliance substrate 30 outside the reservoir 100. Normally, when a functional liquid is supplied from the functional liquid introduction port 25 to the reservoir 100, a pressure change occurs in the reservoir 100 due to, for example, the flow of the functional liquid during driving of the piezoelectric element 300 or ambient heat. However, since the upper portion of the reservoir 100 is the flexible portion 22 sealed only by the sealing film 31 as described above, the flexible portion 22 is bent and deformed to absorb the pressure change. Therefore, the inside of the reservoir 100 is basically maintained at a constant pressure. The other parts are held at a sufficient strength by the fixing plate 32.
The reservoir forming substrate 20 is provided with an introduction path 26 that allows the functional liquid inlet 25 to communicate with the side wall of the reservoir 100.

  In addition, a concave groove 700 extending in the Y-axis direction is formed in the central portion of the reservoir forming substrate 20 with respect to the X-axis direction. In the reservoir forming substrate 20 by the concave groove 700, the first sealing portion 20A for sealing the first piezoelectric element group 300A provided corresponding to the first pressure generating chamber group 12A, and the second pressure generating chamber group 12B. And a second sealing portion 20B for sealing the second piezoelectric element group 300B provided corresponding to the above. Similarly, a third sealing portion (not shown) for sealing a third piezoelectric element group (not shown) provided corresponding to the third pressure generation chamber group 12C, and a fourth pressure generation chamber group 12D. A fourth sealing portion (not shown) that seals a fourth piezoelectric element group (not shown) provided corresponding to is separated by a concave groove 700.

  And in the ditch | groove 700, a part of flow-path formation board | substrate 10 (partition 10K) is exposed. As described above, both side portions of the recessed groove 700 are the stepped portions 250, respectively, and a part of the flow path forming substrate 10 (partition wall 10K) exposed in the recessed groove 700 is The bottom surface of the concave groove 700, that is, the lower step surface (the lower step surface) of the step portion 250.

  A closed space that does not interfere with the operation of the piezoelectric element 300 is secured in a region of the reservoir forming substrate 20 facing the piezoelectric element 300, and this closed space serves as the piezoelectric element holding portion 24. The piezoelectric element holding part 24 is formed in each of the first to fourth sealing parts 20A to 20D (not shown) and covers the first to fourth piezoelectric element groups 300A to 300D (not shown). Is formed. Of the piezoelectric elements 300, at least the piezoelectric film 70 is sealed in the piezoelectric element holding portion 24.

  As described above, the reservoir forming substrate 20 also functions as a sealing member for blocking the piezoelectric element 300 from the external environment and sealing the piezoelectric element 300. That is, by sealing the piezoelectric element 300 with the reservoir forming substrate 20, it is possible to prevent deterioration or destruction of the piezoelectric element 300 due to an external environment such as moisture. Further, in the present embodiment, the piezoelectric element holding part 24 is only sealed, but for example, the piezoelectric element holding part 24 can be evacuated, or the piezoelectric element holding part 24 can be evacuated or a nitrogen or argon atmosphere or the like. The inside of the element holding portion 24 can be held at a low humidity, and the deterioration and destruction of the piezoelectric element 300 can be further reliably prevented.

  The reservoir forming substrate 20 is a rigid body, and as the material for forming the reservoir forming substrate 20, for example, a material substantially the same as the thermal expansion coefficient of the flow path forming substrate 10 such as glass or ceramic material is used. preferable. In this embodiment, a silicon single crystal substrate made of the same material as the flow path forming substrate 10 is used.

  Among the piezoelectric elements 300 sealed by the piezoelectric element holding part 24 of the first sealing part 20A, the end on the −X side of the upper electrode film 80 extends to the outside of the first sealing part 20A as described above. It extends and is exposed on the lower surface of the stepped portion 250 (on the bottom surface of the recessed groove 700) to form a terminal portion 81. In the present embodiment, a part of the lower electrode film 60 extends and is formed on the lower step surface of the stepped portion 250, that is, on the flow path forming substrate 10. Therefore, an insulating film 600 is formed between the lower electrode film 60 and the terminal portion 81 in order to prevent conduction between the lower electrode film 60 and the terminal portion 81 (upper electrode film 80). Similarly, in the piezoelectric element 300 sealed by the piezoelectric element holding part 24 of the second sealing part 20B, the + X side end part of the upper electrode film 80 also extends to the outside of the second sealing part 20B. Terminal portion 81 is formed. Further, although not shown, a part of the upper electrode film 80 of the piezoelectric element 300 that is sealed by the third and fourth sealing portions 20C and 20D (not shown) is formed by the third and fourth sealing portions. It extends to the outside of the stop portions 20 </ b> C and 20 </ b> D and is exposed on the lower surface of the step portion 250, thereby forming a terminal portion 81.

The driver IC (driving circuit unit) 200 for driving the piezoelectric element 300 is a device configured by, for example, a semiconductor integrated circuit (IC) including a circuit board and a driving circuit. In this embodiment, the lower surface 500A of the flexible substrate 500 is used. It is connected to the.
The flexible substrate 500 is made of a flexible circuit board having flexibility, and is made of an insulating film-like member made of polyimide having a thickness of about 25 μm, for example. Note that a conductive wiring pattern (conductive portion) 510 made of a conductive material such as copper is provided on the lower surface 500A of the flexible substrate 500 by a printing method or a method such as plating or etching.

  As shown in FIG. 4, a driver IC 200 is provided in a predetermined region of the lower surface 500 </ b> A of the flexible substrate 500. The driver IC 200 is connected to a part of the wiring pattern 510 by being flip chip mounted on the lower surface 500 </ b> A of the flexible substrate 500. A plurality (four) of driver ICs 200 are provided according to the first to fourth nozzle opening groups 15A to 15D. The first to fourth driver ICs 200 </ b> A to 200 </ b> D provided according to the first to fourth nozzle opening groups 15 </ b> A to 15 </ b> D are flip-chip mounted on the flexible substrate 500, respectively, and are then flexible with the resin 201. 500 is fixed.

  In addition, two openings 520 are formed in part of the flexible substrate 500. These openings 520 are formed to extend in the Y-axis direction in a region between the first driver IC 200A and the second driver IC 200B and a region between the third driver IC 200C and the fourth driver IC 200D, respectively. Cutouts 521 are formed at both ends of the opening 520 in the Y-axis direction. The cutout portion 521 allows a part of the flexible substrate 500 (the edge region) 530 facing the opening 520 to be bent (bend) inside the opening 520. The edge region 530 is a region between each of the driver ICs 200A to 200D and the opening 520, and the edge portion 530E of the edge region 530 that faces the opening 520 is formed substantially linearly along the Y-axis direction. ing. That is, in the present embodiment, the edge region 530 is a rectangular region whose longitudinal direction is the Y-axis direction, and is bent so that the edge portion 530E rotates about the Y-axis (θY direction). ing.

  In the lower surface 500 </ b> A of the flexible substrate 500, a connection terminal portion (connection portion) 512 constituting a part of the wiring pattern 510 is formed in the edge region 530 in the opening portion 520. In the first edge region 530A between the first driver IC 200A and the opening 520, a plurality of connection terminal portions 512 that are electrically connected to the first driver IC 200A via the wiring pattern 510 are formed. The plurality of connection terminal portions 512 provided in the first edge region 530A are patterned so as to be connected to each of the plurality of piezoelectric elements 300 (upper electrode film 80) constituting the first piezoelectric element group 300A. .

  That is, these connection terminal portions 512 are formed in a state where a plurality (for example, 720) are arranged in parallel in the Y-axis direction so as to correspond to the plurality of piezoelectric elements 300 constituting the first piezoelectric element group 300A, This constitutes the first connection terminal group 512A. Therefore, the driver IC 200 is electrically connected to the piezoelectric element 300 via the wiring pattern 510 including the connection terminal portion 512 by connecting the connection terminal portion 512 and the terminal portion 81 on the piezoelectric element 300 side. It has become.

  Similarly, in the second edge region 530B between the second driver IC 200B and the opening 520, a plurality (for example, in the Y-axis direction) corresponding to the plurality of piezoelectric elements 300 constituting the second piezoelectric element group 300B (for example, 720) is provided in a second connection terminal group 512B composed of connection terminal portions 512 formed in parallel. The first edge region 530A and the second edge region 530B are arranged to face each other in the X-axis direction, and the first connection terminals formed in the first and second edge regions 530A and 530B, respectively. The group 512A and the second connection terminal group 512B are also configured to be opposed to each other in the X-axis direction.

  Similarly, the third edge region 530C between the third driver IC 200C and the opening 520 has a plurality in the Y-axis direction so as to correspond to the plurality of piezoelectric elements 300 constituting the third piezoelectric element group 300C. A third connection terminal group 512C composed of connection terminal portions 512 formed in a state where (for example, 720) are arranged in parallel is provided, and a fourth edge region 530D between the fourth driver IC 200D and the opening 520 is provided in the fourth edge region 530D. A fourth connection terminal group consisting of connection terminal portions 512 formed in a state in which a plurality (for example, 720) are arranged in parallel in the Y-axis direction so as to correspond to the plurality of piezoelectric elements 300 constituting the fourth piezoelectric element group 300D. 512D is provided. The third edge region 530C and the fourth edge region 530D are arranged to face each other in the X-axis direction.

Then, as shown in FIG. 3, the edge region 530 in which the connection terminal portion 512 is formed in a state where the lower surface 500A of the flexible substrate 500 and the piezoelectric element 300 are opposed to each other and the opening 520 and the groove 700 are positioned. Since (one end side) is bent downward, the lower surface 500A on the edge region 530 side and the lower step surface of the step portion 250 (the bottom surface of the groove 700) are connected by an anisotropic conductive paste (ACP). . Thereby, the connection terminal portion 512 provided on the lower surface 500A in the edge region 530 of the flexible substrate 500 and the terminal portion 81 of the upper electrode film 80 disposed on the lower step surface of the step portion 250 (the bottom surface of the groove 700). Are electrically connected by conductive particles 561 contained in the anisotropic conductive paste 560, as shown in the sectional side view of the main part of FIG.
As for the flexible substrate 500, when the edge region 530 is bent downward and the connection terminal portion 512 side is inserted into the concave groove 700, the flexible substrate 500 may be bent as necessary.

  Here, in the flexible substrate 500, the edge region 530 (one end side) is bent downward (the bottom surface side of the concave groove 700), and the lower surface 500A on the edge region 530 side and the lower step surface of the step portion 250 (the bottom surface of the concave groove 700). ) Is connected to the flexible substrate 500, and a rising portion 501 rising from the edge region 530 side (one end side) along the stepped portion of the stepped portion 250 is formed. The rising portion 501 is provided with a thermosetting resin 562 in the vicinity 501a on the edge region 530 side (one end side).

With such a configuration, the flexible substrate 500 has a lower surface 500A in which the vicinity 501a on the edge region 530 side (one end side) of the rising portion 501 is fixed to the lower step surface of the stepped portion 250 by the thermosetting resin 562. ing. That is, the flexible substrate 500 has a back fillet formed of the thermosetting resin 562 between the rising portion 501 and the lower step surface of the step portion 250.
The thermosetting resin 562 is made of the same resin as the thermosetting resin 562 in the anisotropic conductive paste 560. That is, the anisotropic conductive paste 560 does not contain the conductive particles 561 and has the same resin component.

Therefore, in the flexible substrate 500, not only the edge region 530 side but also the vicinity 501 a of the rising portion 501 is fixed to the lower step surface of the step portion 250 by the thermosetting resin 562. It is connected to the lower surface with sufficiently high connection strength.
Further, the fixing at the rising portion 501 is made of the same thermosetting resin as the thermosetting resin 562 in the anisotropic conductive paste 560. Therefore, the conductive particles 561 are almost present in the rising portion 501. Therefore, migration due to the conductive particles 561 present in the rising portion 501 is suppressed, and a short circuit between the terminal portions 81 and 81 is prevented.

  Further, since the thermosetting resin 562 used for fixing at the rising portion 501 is the same as the thermosetting resin 562 in the anisotropic conductive paste 560, the edge region of the lower surface 500 </ b> A of the flexible substrate 500 is used. The bonded portion on the 530 side (one end side) and the fixed portion on the rising portion 501 are both formed by a cured product of the same thermosetting resin. Therefore, the bonded portion and the fixed portion exhibit the same thermal behavior, and peeling of the flexible substrate 500 due to a difference in thermal expansion coefficient is prevented.

3 and 4, the first piezoelectric element group 300A corresponds to the first edge region 530A of the flexible substrate 500 and the first connection terminal group 512A provided in the first edge region 530A. The second piezoelectric element group 300B is disposed so as to correspond to the second edge region 530B of the flexible substrate 500 and the second connection terminal group 512B provided in the second edge region 530B. Yes. Therefore, each of the terminal portions 81 (upper electrode film 80) of the plurality of piezoelectric elements 300 constituting the first piezoelectric element group 300A and the plurality of connection terminal portions 512 constituting the first connection terminal group 512A are well connected. In addition, each of the terminal portions 81 (upper electrode film 80) of the plurality of piezoelectric elements 300 constituting the second piezoelectric element group 300B and the plurality of connection terminal portions 512 constituting the second connection terminal group 512B are good. Connected to.
Similarly, the terminal portions 81 of the plurality of piezoelectric elements 300 constituting the third and fourth piezoelectric element groups 300C and 300D and the plurality of connection terminal portions 512 constituting the third and fourth connection terminal groups 512C and 512D are provided. , And the third and fourth edge regions 530C and 530D are connected in a bent state.

  Further, as shown in FIG. 3, a resin 202 is disposed between the flexible substrate 500 and the reservoir forming substrate 20, so that the driver IC 200 provided on the flexible substrate 500 is placed on the reservoir forming substrate 20, that is, It is provided on the upper side of the stepped portion 250. In this state, the flexible substrate 500 and the reservoir forming substrate 20 are fixed by a resin mold made of the resin 202. The resin 202 may also be disposed in the concave groove 700, and a connection portion between the connection terminal portion 512 and the terminal portion 81 (upper electrode film 80) of the piezoelectric element 300 may be resin-molded.

  Next, the operation of the droplet discharge head 1 having such a configuration will be described. In order to eject droplets of functional liquid (ink) from the droplet discharge head 1, the external controller CT shown in FIG. 1 drives an external functional liquid supply device (not shown) connected to the functional liquid inlet 25. . The functional liquid sent out from the external functional liquid supply device fills the internal flow path of the droplet discharge head 1 from the functional liquid introduction port 25 to the reservoir 100 until reaching the nozzle opening 15. Further, the external controller CT sends driving power and a command signal to the driver IC 200 and the like via the external signal input unit 580 provided on the flexible substrate 500. The flexible substrate 500 is provided with a wiring pattern (not shown) different from the wiring pattern 510, and a command signal or the like from the external signal input unit 580 is sent to the driver IC 200 via the wiring pattern. The driver IC 200 applies a voltage between the lower electrode film 60 and the upper electrode film 80 corresponding to the pressure generation chamber 12 via the wiring pattern 510 including the connection terminal portion 512 based on a command from the external controller CT. Is applied to displace the piezoelectric film 70. As a result, the elastic film 50 and the lower electrode film 60 are displaced, the pressure in each pressure generating chamber 12 is increased, and droplets are ejected from the nozzle openings 15.

Next, based on the manufacturing method of the droplet discharge head 1 having such a configuration, an example of the flexible substrate mounting method and the droplet discharge head manufacturing method of the present invention will be described.
When manufacturing the droplet discharge head 1, in particular, the edge region 530 (one end side) of the lower surface 500 </ b> A of the flexible substrate 500 is bonded to the lower step surface of the step portion 250 (bottom surface of the groove 700), and the connection terminal portion 512 is recessed. In order to connect to the terminal portion 81 in the groove 700, that is, the lower surface of the step portion 250, first, a transfer stage 570 as shown in FIG. 6A is prepared.

  The transfer stage 570 is formed with a concave paste containing portion 571 for containing the anisotropic conductive paste before curing, and has a rectangular opening in a plan view. A large number of dimples (recesses) 573 serving as concave portions of the present invention are formed on the bottom surface 572 of the paste containing portion 571. That is, the bottom surface 572 of the paste containing portion 571 is a surface on the transfer stage 570 that forms a paste arrangement region for arranging the anisotropic conductive paste. A large number of dimples 573 such as a bowl inner surface shape or a hemispheric inner surface shape are regularly or irregularly formed on this surface.

  These dimples 573 are formed sufficiently small, for example, about 1 to 3 times the conductive particles contained in the anisotropic conductive paste. Specifically, if the diameter of the conductive particles is 5 μm, the dimples The diameter of 573 is about 5 to 15 μm, preferably about 10 μm. The concave portion in the present invention is not limited to such a dimple shape, and for example, a plurality of grooves having a semicircular cross section or an inverted triangular shape may be arranged in parallel. Also in that case, the width of the groove is preferably about 1 to 3 times that of the conductive particles.

  In addition, one side (one side) of the bottom surface 572 of the paste containing portion 571 is an inclined surface 572 a that is inclined toward the opening of the paste containing portion 571. The inclined surface 572a is gradually inclined toward the upper side from the other bottom surface 572 portion. That is, the inclined surface 572a is a portion that continuously connects the bottom surface 572 and the opening of the paste containing portion 571, and is a portion that is formed in place of the side surface at another location.

  When the transfer stage 570 having such a structure is prepared, the anisotropic conductive paste 560 is filled into the paste containing portion 571 by a dispenser method or the like. In addition, you may apply | coat the mold release material to the inner surface of the paste accommodating part 571 as needed. Then, by squeezing the surface of the transfer stage 570 (the opening surface of the paste containing portion 571), only the anisotropic conductive paste 560 corresponding to the volume is placed in the paste containing portion 571 as shown in FIG. 6B. Contain.

  Next, the anisotropic conductive paste 560 accommodated (arranged) in the paste accommodating portion 571 of the transfer stage 570 is applied to the edge region 530 (one end of the lower surface 500A of the flexible substrate 500 as shown in FIG. 6C). Side). At this time, the front end side (edge region 530) side of the flexible substrate 500 is bent (bent) in advance, and thereby the rising portion 501 rising from the bent portion is formed in the flexible substrate 500. When the edge region 530 (one end side) of the flexible substrate 500 is brought into contact with the anisotropic conductive paste 560, the rising portion 501 side is set to the inclined surface 572a side of the paste containing portion 571.

Thereafter, as shown in FIG. 6D, the edge region 530 (one end side) is pulled up to transfer the anisotropic conductive paste 560 to the edge region 530 (one end side). In this case, as shown by an arrow in FIG. 6D, the pulling is performed obliquely along the surface direction of the inclined surface 572a of the bottom surface 572 of the paste containing portion 571.
When the edge region 530 (one end side) of the flexible substrate 500 is pulled up from the paste accommodating portion 571 of the transfer stage 570 in this way, a large number of dimples (concave portions) 573 are formed on the bottom surface 572 of the paste accommodating portion 571. The accommodated anisotropic conductive paste 560 is easily peeled off from the bottom surface 572, so that almost the entire amount of the anisotropic conductive paste 560 is transferred to the flexible substrate 500.

  That is, when the bottom surface is a continuous flat surface, the adhesive force to the anisotropic conductive paste 560 before curing is strong, and a part of the anisotropic conductive paste 560 tends to remain on the bottom surface side of the transfer stage when pulled up. End up. On the other hand, since a large number of dimples 573 are formed in the transfer stage 570 of this embodiment, the bottom surface 572 of the transfer stage 570 is discontinuous by these dimples 573, and the adhesive force to the anisotropic conductive paste 560 is weakened. Therefore, as described above, the anisotropic conductive paste 560 is easily peeled off from the bottom surface 572.

  In addition, since the edge region 530 (one end side) of the flexible substrate 500 is lifted obliquely along the surface direction of the inclined surface 572a of the bottom surface 572 of the paste containing portion 571 during the pulling, Although the thermosetting resin 562 in the transferred anisotropic conductive paste 560 slightly pulls the thread, the thread is pulled relatively small and diagonally without being pulled largely. Therefore, when pulled up, the pulled yarn immediately falls to the transferred anisotropic conductive paste 560 side. Therefore, since the air that has fallen immediately in such a small pulled state hardly entrains air, it is prevented that the adhesive force is reduced due to bubbles remaining in the anisotropic conductive paste 560. The

At this time, since the edge region 530 of the flexible substrate 500 is lifted obliquely as indicated by an arrow in FIG. 6D, the conductive particles 561 in the paste storage portion 571 are slightly shown in FIG. It moves to the side opposite to the arrow direction in 6 (d).
Note that the anisotropic conductive paste 560 transferred to the edge region 530 of the flexible substrate 500 by such an oblique pull-up has the rising portion 501 side of the flexible substrate 500 particularly on the inclined surface 572a side of the bottom surface 572 of the paste containing portion 571. Corresponding to the shape, an inclined surface 560a is formed as shown in FIG. 6 (d).

In addition to the transfer of the anisotropic conductive paste 560 to the edge region 530 (one end side) of the flexible substrate 500, as shown in FIG. That is, a predetermined amount of thermosetting resin 562 before curing is disposed from the dispenser D, for example, on the lower surface of the stepped portion 250.
Then, as shown in FIG. 7B, the edge region 530 of the flexible substrate 500 to which the anisotropic conductive paste 560 has been previously transferred is inserted into the concave groove 700, and the upper surface side of the flexible substrate 500 is appropriately placed. The edge region 530 is bonded onto the lower surface of the stepped portion 250 via the anisotropic conductive paste 560 by pressing with a pressing block (not shown) or the like.

At this time, the flexible substrate 500 is arranged so that the rising portion 501 side is the stepped portion 250 side, that is, the thermosetting resin 562 side, and is bonded via the anisotropic conductive paste 560. To do. Then, since the thermosetting resin 562 is arranged on the lower surface of the stepped portion 250 in advance, the rising portion 501 side of the lower surface 500A of the flexible substrate 500 is placed on the lower step surface (recessed) of the stepped portion 250 by the thermosetting resin 562. Bonded to the bottom surface of the groove 700.
Thereafter, the anisotropic conductive paste 560 and the thermosetting resin 562 are heated and cured to adhere the edge region 530 of the flexible substrate 500 to the lower surface of the stepped portion 250, and at the same time, the rising portion of the flexible substrate 500. The mounting structure shown in FIG. 5 is obtained by fixing 501 to the lower step surface of the step portion 250 (the bottom surface of the groove 700).

  According to the mounting method of the flexible substrate 500 to the step portion 250 including the concave groove 700, that is, the manufacturing method of the droplet discharge head 1, not only the edge region 530 side but also the edge region 530 (one end of the rising portion 501). The side portion 501a is also fixed to the lower step surface of the step portion 250 by the thermosetting resin 562, so that the flexible substrate 500 can be connected to the lower step surface of the step portion 250 with sufficiently high connection strength.

  Further, since the fixing at the rising portion 501 is performed with the same thermosetting resin as the thermosetting resin 562 in the anisotropic conductive paste 560, the conductive particles 561 hardly exist in the rising portion 501. Therefore, migration due to the presence of the conductive particles 561 in the rising portion 501 can be suppressed, and a short circuit between the terminal portions 81 and 81 can be prevented.

  Note that the anisotropic conductive paste 560 transferred to the edge region 530 of the flexible substrate 500 is obliquely pulled up, so that the side opposite to the arrow direction in FIG. The conductive particles 561 move to the side opposite to the rising portion 501 side of the substrate 500, thereby reducing the content of the conductive particles 561 on the rising portion 501 side. In addition, an inclined surface 560 a corresponding to the inclined surface 572 a of the paste containing portion 571 is formed on the rising portion 501 side of the anisotropic conductive paste 560 transferred to the flexible substrate 500 by oblique pulling.

  Therefore, particularly on the rising portion 501 side in the edge region 530 of the flexible substrate 500, the transfer amount of the anisotropic conductive paste 560 is smaller than that of other portions, and the content of the conductive particles 561 is also reduced. Therefore, on the rising portion 501 side, the absolute amount of the conductive particles 561 is smaller than other portions. Therefore, even if a part of the anisotropic conductive paste 560 transferred to the rising portion 501 side in the edge region 530 wraps around the rising portion 501 during bonding, the absolute amount of the conductive particles 561 is small. The particles 561 are less likely to enter the rising portion 501. Accordingly, it is possible to prevent the conductive particles 561 from wrapping around and moving to the rising portion 501 and causing migration due to the conductive particles 561.

  Further, since the thermosetting resin 562 used for fixing at the rising portion 501 is the same as the thermosetting resin 562 in the anisotropic conductive paste 560, the edge region 530 side of the lower surface 500A of the flexible substrate 500 is used. The bonded portion at (one end side) and the fixed portion at the rising portion 501 are both formed of the same thermosetting resin cured product. Accordingly, the bonded portion and the fixed portion exhibit the same thermal behavior, thereby preventing peeling of the flexible substrate 500 due to a difference in thermal expansion coefficient.

In addition, since a large number of dimples 573 are formed on the bottom surface of the paste accommodating portion 571 that is the formation surface of the paste arrangement region in the transfer stage 570, as described above, when the flexible substrate 500 is lifted from the transfer stage 570, the anisotropic is obtained The conductive conductive paste 560 is easily peeled from the bottom surface 572. Accordingly, almost the entire amount of the anisotropic conductive paste is transferred to the flexible substrate 500. Accordingly, due to variation in the amount of the anisotropic conductive paste 560 transferred to the flexible substrate 500, the flexible substrate 500 is transferred. It is possible to prevent the inconvenience that the connection strength with respect to the lower surface is sufficient.
In addition, since the paste container 571 is formed on the transfer stage 570 and almost the entire amount of the anisotropic conductive paste 560 accommodated in the paste container 571 is transferred, the anisotropy transferred to the flexible substrate 500 is transferred. The amount of the conductive paste 560 can be substantially defined by the volume of the paste containing portion 571, and thus a certain amount of the anisotropic conductive paste 560 can always be transferred to the flexible substrate 500.

  Further, at the time of this lifting, the edge region 530 (one end side) of the flexible substrate 500 is lifted obliquely along the surface direction of the inclined surface 572a of the bottom surface 572 of the paste containing portion 571. It is possible to prevent bubbles from remaining in the anisotropic conductive paste 560. Therefore, it is possible to prevent the adhesive force of the anisotropic conductive paste 560 from being reduced due to the bubbles, thereby preventing the inconvenience that the flexible substrate 500 after mounting is peeled off.

  Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. For example, in the transfer stage, the inclined surface 572a is formed only on one side of the paste containing portion 571, but the inclined surface 572a may be formed on two opposite sides.

<Droplet ejection device>
Next, an example of the droplet discharge apparatus IJ of the present invention provided with the above-described droplet discharge head 1 will be described with reference to FIG. FIG. 8 is a perspective view showing a schematic configuration of the droplet discharge device IJ.

  In FIG. 8, the droplet discharge device IJ includes a droplet discharge head 1, a drive shaft 4, a guide shaft 5, a controller CT, a stage 7, a cleaning mechanism 8, a base 9, and a heater 6. ing. The stage 7 supports the substrate P from which the functional liquid is discharged by the droplet discharge head 1, and includes a fixing mechanism (not shown) that fixes the substrate P at a reference position. The functional liquid is discharged from the nozzle opening of the droplet discharge head 1 onto the substrate P supported by the stage 7.

  A drive motor 2 is connected to the drive shaft 4. The drive motor 2 is composed of a stepping motor or the like. When a drive signal in the Y-axis direction is supplied from the controller CT, the drive shaft 4 is rotated. When the drive shaft 4 rotates, the droplet discharge head 1 moves in the Y-axis direction. The guide shaft 5 is fixed so as not to move with respect to the base 9. The stage 7 includes a drive motor 3. The drive motor 3 is composed of a stepping motor or the like. When a drive signal in the X-axis direction is supplied from the controller CT, the stage 7 is moved in the X-axis direction.

  The controller CT supplies a voltage for controlling droplet ejection to the droplet ejection head 1. Further, the controller CT supplies a drive pulse signal for controlling the movement of the droplet discharge head 1 in the Y-axis direction to the drive motor 2 and moves the stage 7 in the X-axis direction to the drive motor 3. A drive pulse signal for controlling is supplied.

The cleaning mechanism 8 cleans the droplet discharge head 1 and includes a drive motor (not shown). By driving the drive motor, the cleaning mechanism 8 moves in the X-axis direction along the guide shaft 5. The movement of the cleaning mechanism 8 is also controlled by the controller CT. Here, the heater 6 is means for heat-treating the substrate P by lamp annealing, and evaporates and dries the solvent contained in the functional liquid applied on the substrate P. The power on and off of the heater 6 is also controlled by the controller CT.
The droplet discharge device IJ discharges droplets onto the substrate P while relatively scanning the droplet discharge head 1 and the stage 7 supporting the substrate P.

  As described above, such a droplet discharge device IJ includes a droplet discharge head in which peeling at the connection portion of the flexible substrate due to deformation of the flexible substrate 500 (501, 502) is prevented. Also, the droplet discharge device itself is one in which a defect due to peeling of the connecting portion is prevented, and long-term reliability is ensured.

  In the above-described embodiment, the functional liquid discharged from the droplet discharge head 1 includes a liquid crystal display device forming material for forming a liquid crystal display device, and an organic EL forming device for forming an organic EL display device. It includes materials, wiring pattern forming materials for forming wiring patterns of electronic circuits, and the like. Thereby, the droplet discharge apparatus IJ can manufacture each of the devices with the functional liquid discharged based on the droplet discharge method.

1 is an external perspective view of a droplet discharge head according to an embodiment of the present invention. It is the perspective view which looked at the droplet discharge head shown in FIG. 1 from the lower side. It is AA arrow sectional drawing of FIG. It is the figure which looked at the flexible substrate from the lower surface side. It is a principal part sectional side view of a droplet discharge head. (A)-(d) is explanatory drawing of ACP transcription | transfer to a flexible substrate. (A), (b) is explanatory drawing of the mounting method of a flexible substrate. It is an external appearance perspective view which shows an example of a droplet discharge device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Droplet discharge head, 15 ... Nozzle opening, 15A-15D ... Nozzle opening group, 20 ... Reservoir formation board, 81 ... Terminal part, 200 ... Driver IC (drive circuit part), 250 ... Step part, 300 ... Piezoelectric Element (drive element), 500 ... flexible substrate, 501 ... rising part, 501a ... vicinity part, 510 ... wiring pattern (conductive part), 512 ... connection terminal part, 560 ... anisotropic conductive paste, 561 ... conductive particle, 562 ... thermosetting resin, 570 ... transfer stage, 571 ... paste container, 572 ... bottom surface, 572a ... inclined surface, 573 ... dimple, 700 ... concave groove, IJ ... droplet ejection device

Claims (5)

A flexible substrate having a conductive portion is disposed from the upper side to the lower side of the stepped portion, and the flexible substrate is mounted between the upper side and the lower side by the conductive portion.
Adhering one end of the lower surface of the flexible substrate having the conductive portion to the lower surface of the step using an anisotropic conductive paste containing conductive particles in a thermosetting resin, Conducting the conductive portion of the flexible substrate and the terminal portion provided on the lower surface,
The thermosetting resin that is the same as the thermosetting resin in the anisotropic conductive paste at the vicinity of the one end side of the rising portion that rises along the step of the stepped portion from the one end side of the lower surface of the flexible substrate A step of adhering to the lower side surface of the stepped portion by ,
The step of adhering one end side of the lower surface of the flexible substrate to the lower surface of the stepped portion is performed by applying one end side of the lower surface of the flexible substrate to the anisotropic conductive paste before curing disposed on the transfer stage in advance. And transferring the anisotropic conductive paste to the one end side, and then transferring the one end side of the flexible substrate to which the anisotropic conductive paste is transferred to the one end side. And a step of joining to the lower surface of the stepped portion via,
A mounting method for a flexible substrate , wherein a surface on which a paste arrangement region on which the anisotropic conductive paste is to be formed is formed as a plurality of concave portions is used as the transfer stage . The transfer stage is formed with a concave paste containing portion for containing the anisotropic conductive paste, and the bottom surface of the paste containing portion is a surface that forms the paste arrangement region, and the bottom surface One side of the is an inclined surface inclined toward the opening of the paste container,
In the step of transferring the anisotropic conductive paste to one end of the flexible substrate, one end of the lower surface of the flexible substrate is brought into contact with the anisotropic conductive paste and then pulled up, 2. The method for mounting a flexible substrate according to claim 1 , wherein the flexible substrate is pulled up obliquely toward the one side along a surface direction of the inclined surface. A drive circuit portion provided on the upper side of the step portion, a drive element provided on the lower side of the step portion and driven by the drive circuit portion, and the drive circuit portion and the drive element are electrically connected In a manufacturing method of a droplet discharge head comprising a flexible substrate having a conductive portion to be
A method for manufacturing a droplet discharge head, wherein the flexible substrate is mounted by the mounting method according to claim 1 . A drive circuit portion provided on the upper side of the step portion, a drive element provided on the lower side of the step portion and driven by the drive circuit portion, and the drive circuit portion and the drive element are electrically connected In a droplet discharge head provided with a flexible substrate having a conductive portion to be
A droplet discharge head, wherein the flexible substrate is mounted by the mounting method according to claim 1 . A droplet discharge apparatus comprising the droplet discharge head according to claim 4 .

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