JP2007290327A - Inkjet printhead and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a substrate from being brought into contact with a front end of a TAB flying lead by enlarging a pad without changing the size of the substrate when the flying lead and the substrate pad are electrically connected to each other. <P>SOLUTION: The front end of the TAB flying lead 11 is formed inside the pad of the substrate 1, and wiring 4 and an insulating film 3 are formed under the pad on the front end of the flying lead 11 away from the current-carrying part of the pad wiring. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is an ink jet print head that performs recording by ejecting liquid to form flying droplets, and electrically connecting an electrical connection terminal of a substrate having an ejection energy generating element and an electrical wiring member having a flying lead portion. In this case, the flying lead is positioned inside the electrical connection terminal, and a wiring and an insulating film covering the wiring are formed below the electrical connection terminal at a portion positioned at the tip of the flying lead. It relates to the print head.

  The liquid discharge head of the present invention includes a printer, a copying machine, a facsimile having a communication system, which records on a recording medium such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, etc. The present invention is applied to a liquid discharge head used in an apparatus such as a word processor having a printer unit, and an industrial recording apparatus combined with various processing apparatuses.

  [Recording] in the present invention means not only giving an image having a meaning such as a character or a figure to a recording medium but also giving an image having no meaning such as a pattern.

  As conventional electrical connection methods, bumps are formed on the electrical connection terminals of the substrate, and the flying leads are positioned and electrically connected, or the surface of the electrical connection terminals is plated and the flying leads are positioned and electrically connected. Methods are known. In the case of electrical connection using bumps, pressure is applied to the electrical connection terminals when the bumps are formed. Therefore, when the damage to the electrical connection terminals is taken into account, the latter plating method is more advantageous as the electrical connection method. In addition, when increasing the number of electrical connection terminals due to finer wiring or reducing the chip size, the plating process is also performed from the viewpoint of reducing the size of the electrical connection terminals and reducing the distance between the terminals. The method is more advantageous. The plating process is usually formed with a thickness of about several μm. Moreover, as shown in the drawing of Patent Document 1 below, the tip of the flying lead is formed to the outside of the electrical connection terminal from the viewpoint of positioning accuracy and the like.

  There is also an inkjet print cartridge product in which the electrical connection terminal is enlarged and the leading end of the flying lead is formed inside the electrical connection terminal.

As an electrical connection method, there is a case where the electrical connection terminal and the flying lead are positioned in a state where a step is provided, and electrical connection is performed in that state. When electrical connection is made, the connecting jig pushes the flying lead, so that the lead tip first contacts the substrate surface, and then the electrical connection portion is grounded and electrically connected to the electrical connection terminal.
Japanese Patent Laid-Open No. 2002-19130

  However, the conventional techniques have the following problems.

  Usually, in order to supply electricity to the energy generating element, a plurality of wirings made of Al or the like are stretched over the substrate, and a multilayer structure is formed depending on the location. A plurality of insulating films such as SiO and SiN for protecting the wiring are laminated on the surface. Since such wiring and insulating film are formed of a very thin film, there is a possibility that the wiring or the insulating film may be broken by a slight impact. For example, when the flying lead is electrically connected to the electrical connection terminal, a crack is generated by the impact of the flying lead contacting the substrate surface. When a crack occurs in an insulating film, ink or the like enters from that portion to cause an electrical short circuit, and when the crack reaches the wiring portion, there is a problem that current is not supplied. Thus, the ink jet print head may not operate due to the occurrence of cracks.

  In order to cope with this, the electrical connection terminals have been enlarged to prevent the flying leads from coming into contact with the substrate surface. However, simply increasing the electrical connection terminals results in an increase in the substrate and cost. There is a problem.

  The present invention has been made paying attention to the above-mentioned problems, and the pad is enlarged without changing the size of the substrate, and when the TAB flying lead and the substrate pad are electrically connected, the substrate and the tip of the flying lead are in contact with each other. It is an object of the present invention to provide an ink jet print head capable of preventing the above and a manufacturing method thereof.

  In order to solve the above problems, the present invention has the following configuration.

(1) A plurality of energy generating elements that generate energy for ejecting ink, a wiring for transmitting a driving signal to each energy generating element, an insulating film for protecting the wiring, and the wiring An opening of the insulating film for supplying a signal; and a conductor electrically connected to the wiring at the opening, the conductor being formed of the wiring, the opening, and the opening. A substrate formed in an upper layer of the surrounding insulating film;
An electrical wiring member having a flying lead,
In the inkjet print head in which the conductor and the flying lead are electrically connected,
The leading end of the flying lead is located inside the conductor, the lower layer of the conductor where the leading end of the flying lead is located is formed with the wiring and the insulating film, and the flying lead is the opening of the conductor. An ink jet print head characterized by being electrically connected in an upper layer portion of the ink jet print head.

  (2) The inkjet print head according to (1), wherein at least a part of a tip of the flying lead is formed outside the conductor.

  (3) The inkjet print head according to (1) or (2), wherein the insulating film is formed of a plurality of layers.

  (4) The wiring according to any one of (1) to (3), wherein the wiring formed in a lower layer of a portion other than the upper layer portion of the opening of the conductor is formed of a plurality of wires. The inkjet printhead as described.

  (5) The inkjet print head according to (4), wherein the plurality of wirings formed in a lower layer of a portion other than the upper layer portion of the opening of the conductor are formed in a multilayer. .

  (6) The ink jet print head according to any one of (1) to (5), wherein the surface of the conductor and the surface of the flying lead are made of the same material.

  (7) The ink jet print head according to (6), wherein the material of the surface of the conductor and the surface of the flying lead is made of gold.

  (8) The ink jet print head according to any one of (8) to (7), wherein the conductor is formed higher than the surface of the substrate.

  (9) The surface of the conductor and a surface of a portion other than the upper layer portion of the opening of the conductor are formed on the same plane, according to any one of (1) to (8), Inkjet printhead.

(10) A plurality of energy generating elements that generate energy for ejecting ink, a wiring for transmitting a drive signal to each of the energy generating elements, an insulating film for protecting the wiring, and the wiring An opening of the insulating film for supplying a signal to the wiring, and a conductor electrically connected to the wiring at the opening, the conductor being the wiring, the opening, and A substrate formed in an upper layer of the insulating film around the opening;
An electrical wiring member having a flying lead,
In the method of manufacturing an ink jet print head in which the conductor and the flying lead are electrically connected,
The leading end of the flying lead is located inside the conductor, and the lower layer of the conductor where the leading end of the flying lead is located is formed with the wiring and the insulating film, and the flying lead is the conductor of the conductor. An ink jet print head manufacturing method, wherein electrical connection is made on an opening.

  (11) When performing the electrical connection, the electrical wiring member is positioned so that the flying lead is positioned above the conductor of the substrate, and the electrical connection is performed using the electrical connection jig in that state. The method for producing an ink jet print head according to (10), wherein:

  The effects of the present invention are as follows.

  By forming at least a part of the tip of the flying lead formed on the electric wiring member inside the electric connection terminal of the substrate having the energy generating element, the tip of the flying lead that comes into contact with the substrate at the time of electric connection is divided into the electric connection terminal. Since it is not in contact with anything other than the above, damage to the wiring formed on the substrate can be prevented.

  In addition, since the insulating film is formed on the flying lead tip side from the electrical connection portion under the electrical connection terminal portion, it is not necessary to enlarge the opening of the wiring, so that the size of the substrate is not changed. In addition, it is possible to enlarge the electric wiring connecting terminal portion.

  According to the present invention, an electrical connection terminal provided on a substrate having an energy generating element and a flange lead portion of an electric wiring member having a flying lead are electrically connected in advance to an ink discharge port provided in the substrate having the energy generating element. The present invention relates to an electrical connection method between a substrate having an energy generating element and an electrical wiring member having a flying lead in an ink jet print head formed by being bonded to an ink supply member or an ink supply auxiliary member for supplying ink.

  Examples of the present invention are shown below.

[First embodiment]
1 and 2 are schematic diagrams used in the first embodiment of the present invention. In the figure, 1 is a substrate having an energy generating element, 2 is an electrical connection terminal provided on the substrate 1 having the energy generating element (corresponding to the conductor of claims 1 and 10), 4 is an energy generating element ( Wiring for transmitting a drive signal to (not shown), 3 is an insulating film for protecting the wiring 4, 10 is an electrical wiring member having flying leads, 11 is a flying lead, and 20 is electrical wiring having the flying leads. This is a jig for electrically connecting the member 10. The electrical connection terminal 2 includes an electrical connection portion (corresponding to the upper layer portion of the opening portion in claims 1 and 10) 5 in which an insulating film 3 protecting the wiring is opened in a lower layer of the electrical connection terminal 2, and an electrical connection It comprises a lower layer protection portion (corresponding to a portion other than the upper layer portion of the opening portion of claims 1 and 10) in which wiring and an insulating film are formed in the lower layer of the terminal 2.

  Hereinafter, the electrical connection process of the electrical connection terminals 2 on the substrate 1 and the flying leads 11 of the electrical wiring member 10 will be described with reference to FIG. In this example, electrical connection was performed by a gang bonding method.

  FIG. 2A: Flying lead 11 of electrical wiring member 10 is placed on electrical connection terminal 2 formed on substrate 1 such that a part of the tip of flying lead 11 enters inside electrical connection terminal 2. Positioning is performed over the substrate 1.

  FIG. 2B: The jig 20 for electrical connection is heated to 450 ° C. in advance. When the heated jig 20 is lowered onto the flying lead 11 toward the substrate 1, the flying lead 11 is deformed as the jig 20 descends. Thereafter, first, the tip of the flying lead 11 comes into contact with the electrical connection terminal 2.

  FIG. 2C: When the jig 20 is lowered as it is, the electrical connection terminal 2 and the flying lead 11 come into contact with each other. Since heat and pressure are applied by the jig 20, the contact portions of the electrical connection terminals 2 and the flying leads 11 are melted and connected to each other.

  FIG. 2D: Even after the jig 20 is released, the electrical connection terminal 2 and the flying lead 11 are melted to each other so that they are not separated from each other. In this way, the electrical connection portion 21 was formed.

  In the electrical connection portion 21 manufactured in this way, the tip of the flying lead 11 did not come in contact with anything other than the electrical connection terminal 2 on the substrate 1, so that no crack 30 was generated on the substrate 1.

  If the electrical connection terminal 2 is enlarged without forming an insulating film below the electrical connection terminal 2, the substrate 1 is also enlarged accordingly. This is not preferable because the cost of the substrate 1 is increased.

  Therefore, as in this embodiment, the insulating film 3 is formed on the leading end side of the flying lead 11 with respect to the electrical connection portion 21 below the electrical connection terminal 2, so that the electrical connection terminal 2 can be formed without changing the size of the opening. Since it can be formed large, the electrical connection terminal 2 can be enlarged to the tip of the flying lead 11 without enlarging the substrate 1.

  Further, when the electrical connection is made, pressure is applied by the electrical connection jig 20. For this reason, if the insulating film 3 is formed in the lower layer of the portion where the electrical connection terminal 2 is electrically connected, the insulating film 3 is broken by the pressure of the electrical connection jig 20. Therefore, it is necessary to form the electrical connection part 5 and the lower layer protection part 6 (refer FIG. 1) in the electrical connection terminal 2 like a present Example.

  Moreover, since the surface of the electrical connection terminal 2 and the flying lead 11 is the same member, there are two effects. As a first effect, the connection between the electrical connection terminal 2 and the flying lead 11 can be formed physically and firmly. Since both surfaces are the same members, the melting temperatures are equal. For this reason, the influence of heat applied at the time of connection is the same, and since they melt together, a strong connection becomes possible. Further, as a second effect, the connection can be made without damaging each other's surface. This is because when the electrical connecting jig 20 presses the flying lead 11, the tip of the flying lead 11 comes into contact with the electrical connecting terminal 2 (FIG. 2B).

  Until the electrical connection jig 20 is lowered to the position for electrical connection (FIG. 2 (c)), the tip of the flying lead 11 moves while contacting the electrical connection terminal 2, but if it is made of a different material, the soft material side May be scratched. This may cause a weak connection. However, if they are formed from the same member, they will not damage each other when they move in contact with each other, and the connection can be made strong. These methods are effective because the electrical connection terminal 2 becomes smaller and the area of the electrical connection portion becomes smaller with respect to the miniaturization and higher definition of the inkjet head, so that the electrical connection can be made firmly. Seem.

[Second Embodiment]
FIG. 3 is a schematic view showing a second embodiment of the present invention. In the figure, 1 is a substrate having an energy generating element, 2 is an electrical connection terminal provided on the substrate 1 having the energy generating element, 4 is a wiring for transmitting a drive signal to the energy generating element (not shown), 3 Is an insulating film for protecting the wiring 4, 7 is a second insulating film for protecting the wiring 4, 10 is an electrical wiring member having flying leads, 11 is a flying lead, and 20 is the flying lead. It is a jig | tool at the time of electrically connecting the electric wiring member 10 which has.

  In the electrical connection terminal 2, an electrical connection portion 5 in which an insulating film 3 protecting the wiring 4 is opened in a lower layer of the electrical connection terminal 2, and a wiring 4 and an insulating film 3 are formed in the lower layer of the electrical connection terminal 2. It consists of a lower layer protection part 6. In this embodiment, the wiring 4 is formed in two layers with the second insulating film 7 sandwiched between the lower protective portion 6 of the electrical connection terminal 2 and insulated on the surface of the substrate 1 of the wiring 4 located in the upper layer. A film 3 is formed.

  As shown in FIG. 3A, the shape of the electrical connection terminal 2 of the substrate 1 in the present embodiment is such that the leading end side of the flying lead 11 is narrowed. The electrical connection was made in the same manner as in the first example except that this substrate 1 was used.

  In the electrical connection portion thus manufactured, the tip of the flying lead 11 does not come in contact with any part other than the electrical connection terminal 2 on the substrate 1, so that the crack 30 on the substrate 1 did not occur.

  Since the area of the electrical connection terminal 2 extending to the front end side of the flying lead 11 of the substrate 1 can be reduced as in the second embodiment, the area of the electrical connection terminal 2 can be made smaller than that in the first embodiment. It is possible to reduce costs such as.

  Further, as in the present embodiment, by forming the plurality of wirings 4 and the insulating films 3 and 7 below the electrical connection terminal 2, it becomes possible to form a wiring pattern on the lower layer of the electrical connection terminal 2. It is possible to reduce the size of.

[Third embodiment]
The present embodiment shows an example of an ink jet print head using the method for electrically connecting electric wiring members having flying leads of the present invention.

  The ink jet print head H1000 is a bubble jet (registered trademark) type ink jet print head using an electrothermal transducer that generates thermal energy for causing film boiling to the ink in response to an electric signal. This is a so-called side shooter type ink jet print head in which the electrothermal transducer and the ink discharge port are arranged to face each other.

(1) Inkjet print head H1000
6 and 7 are exploded perspective views of the ink jet print head H1000. The inkjet print head H1000 includes a substrate H1100 having energy generating elements, an electrical wiring member_H1300 having flying leads, an ink supply holding member H1500, a filter H1700, an ink absorber H1600, a lid member H1900, and a seal member H1800. .

(1-1) Substrate H1100 having energy generating elements
FIG. 8 is a diagram for explaining the configuration of the substrate H1100 having the energy generating elements, and is a partially broken perspective view. The substrate H1100 having the energy generating element is anisotropic, for example, by using a Si substrate H1110 having a thickness of 0.5 mm to 1 mm and an ink supply port H1102 having a long groove-like through-hole serving as an ink flow path by utilizing the crystal orientation of Si. It is formed by a method such as etching or sand blasting.

  On the Si substrate H1110, energy generating elements H1103 are arranged side by side on both sides of the ink supply port H1102, and electric wiring (not shown) made of Al or the like that supplies power to the energy generating elements H1103 is arranged. Is formed. In addition, an insulating film (not shown) made of SiO or SiN is formed on the surface of the Si substrate H1110 other than the energy generating element H1103 and the electrical connection terminal H1104 using an existing film forming technique. These energy generating elements H1103 and electrical wiring can be formed by using an existing film forming technique. The energy conversion elements H1103 in each column are arranged in a staggered manner. In other words, the positions of the ejection ports in each row are slightly shifted so as not to line up in a direction orthogonal to the row direction.

  In the substrate H1100 having energy generation elements, the ink supplied from the ink supply port H1102 is discharged from the discharge port 1107 facing each energy generation element H1103 by the pressure of the bubbles generated by the heat generation of each energy generation element H1103. .

(1-2) Electric wiring member H1300 having flying leads
The electrical wiring member H1300 having flying leads forms an electrical signal path for applying an electrical signal for ejecting ink to the substrate H1100 having energy generating elements, and a copper foil is formed on the polyimide base substrate. This wiring pattern is formed. Further, an opening H1303 for incorporating the substrate H1100 having the energy generating element is formed, and the flying lead connected to the electrical connection terminal H1104 of the substrate H1100 having the energy generating element is formed near the edge of the opening H1303. A portion H1304 is formed. The surface of the flying lead is subjected to gold plating.

  Furthermore, an external signal input terminal H1302 for receiving an electrical signal from the main unit is formed on the electrical wiring member H1300 having a flying lead, and a copper foil in which the external signal input terminal H1302 and the flying lead portion H1304 are continuous. It is connected with the wiring pattern.

  The electrical connection between the electrical wiring member H1300 having flying leads and the substrate H1100 having energy generating elements includes, for example, the electrical connection terminal H1104 of the substrate H1100 having the energy generating elements subjected to gold plating and the energy generating elements. The flying lead portion H1304 of the electrical wiring member H1300 having a flying lead corresponding to the electrical connection terminal H1104 of the substrate H1100 is electrically connected according to the positional relationship of the present invention.

(1-3) Ink supply holding member H1500
The ink supply holding member H1500 is formed by, for example, resin molding. As the resin material, it is desirable to use a resin material mixed with 5 to 40% of glass filler in order to improve the shape rigidity. As shown in FIG. 7, the ink supply / holding member H1500 has an absorber H1600 for holding ink therein and generating negative pressure so as to guide the ink tank to the recording element substrate H1100. The ink supply function is realized by forming the ink flow paths. As the ink absorber H1600, a compressed PP fiber is used. Alternatively, a compressed urethane fiber may be used.

  A filter for preventing dust from entering the inside of the substrate H1100 having an energy generating element at a boundary portion between the ink flow path and a portion to which ink from the ink absorber H1600 located upstream of the ink flow path is supplied. H1700 is joined by welding. The filter H1700 may be a SUS metal mesh type, but is preferably a SUS metal fiber sintered type.

  An ink supply port H1200 for supplying black ink to the substrate H1100 having energy generating elements is formed in the downstream portion of the ink flow path, and the ink supply port 1102 of the substrate H1100 having energy generating elements supplies ink. A substrate H1100 having an energy generating element is bonded and fixed to the ink supply holding member H1500 with high positional accuracy so as to communicate with the ink supply port H1200 of the holding member H1500. The first adhesive used for the bonding is desirably a low viscosity, low curing temperature, cured in a short time, and has a relatively high hardness after curing and ink resistance. As this 1st adhesive agent, there exists a thermosetting adhesive agent which has an epoxy resin as a main component, for example. When this thermosetting adhesive is used, the thickness of the adhesive layer is desirably about 50 μm.

  In addition, a part of the back surface of the electric wiring member H1300 having flying leads is bonded and fixed to the plane around the bonding surface of the substrate H1100 having the energy generating element by the second adhesive. The electrical connection portion between the substrate H1100 having the energy generating element and the electrical wiring member H1300 having the flying lead is sealed with the first sealant H1307 and the second sealant H1308 (see FIG. 9), thereby Protects electrical connections from ink corrosion and external impacts. The first sealant H1307 mainly includes the back surface side of the connecting portion between the flying lead portion H1304 of the electric wiring member H1300 having the flying lead and the bump H1105 of the substrate H1100 having the energy generating device, and the substrate H1100 having the energy generating device. The second sealing agent H1308 seals the front side of the connecting portion. The unbonded portion of the electric wiring member H1300 having the flying lead is bent and fixed to the side surface substantially perpendicular to the bonding surface of the substrate H1100 having the energy generating element of the ink supply holding member H1500 by heat caulking or bonding.

(1-4) Lid member H1900
The lid member H1900 seals the inside of the ink supply holding member H1500 by being welded to the upper opening of the ink supply holding member H1500. The lid member H1900 is provided with a narrow opening H1910 for releasing pressure fluctuation inside the ink supply holding member H1500 and a fine groove H1920 communicating with the narrow opening H1910. Most of the narrow opening H1910 and the fine groove H1920 are covered with a sealing member H1800, and one end of the fine groove H1920 is opened to form an air communication opening. The lid member H1900 has an engaging portion H1930 for fixing the ink jet print head to the ink jet recording apparatus.

(A) typical top view showing the 1st embodiment of the present invention, (b) typical sectional view Schematic showing the deformation of the flying lead part during the electrical connection process of the present invention (A) Schematic diagram of electrical connection terminal, (b) Schematic top view, (c) Schematic sectional view showing the second embodiment of the present invention The electrical connection state which does not carry out the form of the present invention is represented by (a) a schematic top view and (b) a schematic sectional view. The schematic diagram showing the deformation | transformation of the flying lead part in the electrical connection process which does not perform the form of this invention Schematic diagram of an ink jet print head using the method of the present invention Schematic diagram of component configuration of ink jet print head using the method of the present invention Schematic diagram of a substrate having the energy generating element of the present invention Sectional drawing of a part of the inkjet printhead of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Board | substrate 2 Electrical connection terminal 3 Insulating film 4 Wiring 5 Electrical connection part 6 Lower layer protective part 7 Second insulating film 10 Electrical wiring member 11 having a flying lead Flying lead 20 Electrical connection jig 21 Electrical connection part 30 Crack

Claims (11)

A plurality of energy generating elements that generate energy for discharging ink, a wiring for transmitting a drive signal to each of the energy generating elements, an insulating film for protecting the wiring, and a signal to the wiring An opening portion of the insulating film to be connected and a conductor electrically connected to the wiring at the opening, and the conductor is around the wiring, the opening, and the opening A substrate formed in an upper layer of the insulating film;
An electrical wiring member having a flying lead,
In the inkjet print head in which the conductor and the flying lead are electrically connected,
The leading end of the flying lead is located inside the conductor, the lower layer of the conductor where the leading end of the flying lead is located is formed with the wiring and the insulating film, and the flying lead is the opening of the conductor. An ink jet print head characterized by being electrically connected in an upper layer portion of the ink jet print head.   The inkjet print head according to claim 1, wherein at least a part of a tip of the flying lead is formed outside the conductor.   The inkjet print head according to claim 1, wherein the insulating film is formed of a plurality of layers.   4. The ink jet print head according to claim 1, wherein the wiring formed in a lower layer of a portion other than an upper layer portion of the opening of the conductor is formed of a plurality of wires. 5.   The inkjet print head according to claim 4, wherein a plurality of the wirings formed in a lower layer of a portion other than the upper layer portion of the opening of the conductor are formed in a multilayer.   6. The ink jet print head according to claim 1, wherein the surface of the conductor and the surface of the flying lead are made of the same material.   7. The ink jet print head according to claim 6, wherein the surface of the conductor and the surface of the flying lead are made of gold.   8. The ink jet print head according to claim 1, wherein the conductor is formed higher than the surface of the substrate.   9. The ink jet print head according to claim 1, wherein the surface of the conductor and the surface of a portion other than the upper layer portion of the opening of the conductor are formed on the same plane. A plurality of energy generating elements for generating energy for ejecting ink; wiring for transmitting a driving signal to each of the energy generating elements; an insulating film for protecting the wiring; and the wiring in the wiring An opening of the insulating film for supplying a signal to a conductor, and a conductor electrically connected to the wiring at the opening, the conductor being the wiring, the opening, and the opening A substrate formed in an upper layer of the insulating film around
An electrical wiring member having a flying lead,
In the method of manufacturing an ink jet print head in which the conductor and the flying lead are electrically connected,
The leading end of the flying lead is located inside the conductor, and the lower layer of the conductor where the leading end of the flying lead is located is formed with the wiring and the insulating film, and the flying lead is the conductor of the conductor. An ink jet print head manufacturing method, wherein electrical connection is made on an opening.   When performing the electrical connection, the electrical leads of the electrical wiring member are positioned so that the flying leads are positioned above the conductor of the substrate, and electrical connection is performed using an electrical connection jig in that state. A method for manufacturing an ink jet print head according to claim 10.