JPH07144406A - Ink jet recording head and ink jet recorder - Google Patents

Abstract

PURPOSE:To provide an ink jet recording head with high workability which can decrease the length of wiring between a silicon substrate, a driving IC and a wiring substrate. CONSTITUTION:A driving IC 120 is provided with an IC element mounted on a junction substrate. An IC junction terminal is led out with the wiring pattern of the junction substrate on the junction side. Namely, the junction terminal which is connected with the electric thermal conversion element of a silicon substrate 100 is led out to a junction electrode near the silicon substrate of the junction substrate. The wiring conductor 160 of the wiring substrate 150 connected with the silicon substrate is also led out to an outer edge near the silicon substrate. It is thus possible to carry out junction between the silicone substrate, the driving IC, and the wiring substrate by means of short wiring, for example, bonding wires 130, 135 with high workability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording head for recording by ejecting a recording liquid (ink or the like) as droplets from a discharge port (orifice) and adhering it to a recording medium. The present invention relates to an inkjet recording device used.

[0002]

2. Description of the Related Art A conventional ink jet recording head, as described in JP-A-55-132253, has an electrothermal converter formed on a silicon substrate, a recording ink ejection port on the silicon substrate, and an electric recording medium. It is configured by joining an ink flow path having a heat acting portion by a heat conversion body and a top plate having a recess for forming a common liquid chamber that supplies ink to the ink flow path. In many cases, the ink jet recording head is provided with a driving IC for driving the electrothermal converter arranged on the silicon substrate, a silicon substrate, and a wiring substrate for drawing out wiring from the driving IC. The silicon substrate, the driving IC, and the wiring substrate are arranged adjacent to each other on the heat dissipation member.

Electrical connection between the driving IC and one terminal of the electrothermal converter arranged on the silicon substrate is performed by a pad provided at the end of the aluminum wiring drawn out from the electrothermal converter and the driving terminal. Wire bonding is performed between the pads provided at the IC end. Further, the other power source common terminal of the electrothermal converter is collectively led to the end portion of the silicon substrate by the two-layer wiring and connected to the power source common terminal on the wiring board by wire bonding. Conventionally,
The driving IC is arranged between the wiring board and the silicon substrate provided with the electrothermal converter, and the wiring board is electrically connected to the power supply common terminal of the silicon substrate provided with the heat converter by wire bonding.

[0004]

However, according to the above-mentioned conventional example, the driving IC is arranged between the wiring board and the silicon substrate provided with the electrothermal converter, and the electrothermal converter is provided from the wiring board. When the electrical connection is made to the power supply terminal of the silicon substrate by wire bonding, the driving IC
Method of performing wire bonding over the wiring board, or changing the shape of the wiring board and bringing the wiring board close to the silicon substrate provided with the heat conversion body by passing the side of the driving IC through a part of the wiring board to perform wire bonding. There is.

However, there is a problem in any of the methods. In the former method, there is a problem that the length of the bonding wire becomes long, which leads to a decrease in yield in making, and in the latter case, when the shape of the wiring board becomes irregular and an attempt is made to reduce the size. It causes a decrease in processing yield,
Further, since the wiring of the power source can be connected only at both ends of the silicon substrate on the silicon substrate provided with the heat conversion element, it is necessary to form the wiring on the silicon substrate in two layers, which is a factor of cost increase.

In view of the above problems, it is an object of the present invention to provide an ink jet recording head which can shorten the length of wiring between a silicon substrate, a driving IC and a wiring substrate and has good workability.

[0007]

An ink jet recording head according to the present invention includes an electrothermal converter for generating ejection energy for ejecting ink held in a common liquid chamber from an ejection port, and an electrothermal converter for the electrothermal converter. First connected to the power supply line
An ink jet recording head in which a silicon substrate having a connecting electrode and a wiring substrate that carries wiring to the silicon substrate are closely fixed to each other on a heat dissipation member, the silicon substrate of the wiring substrate A second connection electrode connected to the wiring of the wiring board and connected to the first connection electrode is provided on the side, and the drive member for driving the electrothermal converter is a connection board. Mounted on the wiring board in the vicinity of the silicon substrate and connected to the electrothermal converter among the connection terminals of the driving member, the connection board is connected to the connection board by the wiring pattern of the connection board. To a third connection electrode provided on the silicon substrate side of the first substrate of the silicon substrate.
The connection between the second connection electrode of the wiring substrate and the second connection electrode of the wiring substrate and the connection between the first connection electrode of the silicon substrate and the third connection electrode of the connection substrate are directly performed by the conductive member.

[0008]

The connection terminal to be connected to the electrothermal converter is connected to the third connection electrode provided on the silicon substrate side of the connection board by the wiring pattern of the connection board. It has been derived. Therefore,
The connection between the third connection electrode and the first connection electrode does not require connection beyond the drive member or wiring around the drive member.

That is, by connecting the drive member and the silicon substrate and the wiring substrate and the silicon substrate by, for example, wire bonding, the length of the bonding wire is not made too long, and the shape of the wiring substrate is made different. Therefore, it is possible to manufacture an ink jet recording head without reducing the production yield of the wiring board and without forming the wiring on the silicon substrate in two layers.

[0010]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a sectional view showing a first embodiment of an ink jet recording head of the present invention. Reference numeral 100 is a silicon substrate provided with an electrothermal converter and electric wiring, 110 is a discharge port and a common liquid chamber forming member formed on the silicon substrate, and 120 is a driving IC. Driving IC 120
Is mounted on a connection board, and each connection terminal is appropriately guided to a connection electrode (bonding pad) provided on the outer edge of the connection board by the pattern of the connection board.
In particular, the silicon substrate 1 among the connection terminals of the driving IC 120
The connection terminal connected to 00 is led out to the connection electrode on the silicon substrate 100 side by the wiring pattern of the connection substrate.

Reference numeral 130 is a silicon substrate 100 and a driving IC.
By arranging the bonding pads in a staggered manner with the bonding wires for making 120 electrical connections, the height of the loop of the bonding wires is changed, and the density of the bonding wires is improved. A bonding wire 135 connects between the wiring board 150 and the silicon substrate 100, but the height of the loop is equal to the bonding wire 13.
It is lower than the height of the loop of 0. Therefore, FIG.
(1), it is shown that the bonding wire loop has a total of three stages.

Reference numeral 140 denotes a heat dissipation member, which is made of aluminum. Reference numeral 150 denotes a wiring board, and a printed board is used in this embodiment. The driving IC 120 is mounted on the resist 220 on the left side of the wiring board 150, and is electrically connected to the silicon substrate 100 provided with the electrothermal converter and the electric wiring by the bonding wire 130. In the present embodiment, it is desirable to adopt Au ball thermosonic bonding for wire bonding between the ejection port and the common liquid chamber forming member and the driving IC. Reference numeral 160 denotes a wiring conductor of the wiring board 150, and in particular, a wire bonding pad is plated with Au for wire bonding.

Reference numeral 180 denotes a wiring conductor 160 of the wiring board 150.
Is a thermosetting epoxy-based solder resist or a UV-curing solder resist that covers the. Reference numeral 190 is an adhesive layer for bonding the wiring board 150 and the heat dissipation member 140, and 200 is the silicon substrate 100 and the heat dissipation member 140.
It is an adhesive layer for bonding and. In FIG. 1, the ink flow paths are not shown for the sake of clarity.

In the electrothermal converter and the electric wiring of the silicon substrate 100, for example, a SiO ₂ film having a thickness of 1 to 3 μm is formed on the surface of a silicon wafer by thermal oxidation, and a HfB ₂ film serving as a heating resistor is formed on the SiO ₂ film by 400 μm. ~ 2000Å, Ti which is the adhesion improving layer is 10-100Å, and electrode material Al is 30
A film is formed by sputtering from 00 to 10000Å, and a pattern is formed by a photolithography process so that a desired heating element shape and electrode shape can be obtained. Next, SiO ₂ or Si ₃ N ₄ is formed as a protective layer by 1-2 μm sputtering or CVD method.

Therefore, according to the present embodiment, the solder resist 220 is applied on the wiring board (printed wiring board), and the driving IC 120 is further adhered thereon by an insulating epoxy-based adhesive or the like. Mounted as a drive IC1
A wiring conductor 160 is provided on the wiring board 150 between the 20 and the silicon substrate 100 having the electrothermal converter and the electric wiring, and the wiring conductor 160 serves as a common power supply pattern. A bonding wire 135 is provided between the common electrode of the electrothermal converter at each ejection port of the silicon substrate 100 and the common power source pattern on the printed wiring board, and between the segment wiring of the electrothermal converter at each ejection port and the driving IC. The bonding wire 1
Bonding connection is made at 30. As a result, the wiring to the common electrode on the silicon substrate 100 provided with the heat conversion element and the electric wiring does not have to be formed in two layers, and it is possible to form one layer. Therefore, it is possible to reduce the thin film forming process and the thin film photolithography process for forming the silicon substrate provided with the electrothermal converter and the electric wiring, and thus it is possible to provide an inexpensive inkjet recording head.

Next, a second embodiment of the present invention will be described with reference to the sectional view of FIG. Reference numeral 100 is a silicon substrate provided with an electrothermal converter and electric wiring, 110 is a discharge port and a common liquid chamber forming member formed on the silicon substrate, and 120.
Is a driving IC, 130 is a silicon substrate 100 and a driving I.
The bonding density is improved by arranging the bonding pads in a zigzag manner with the bonding wires for electrically connecting C120 and changing the height of the loop of the bonding wires. A bonding wire 135 connects between the wiring board 150 and the silicon substrate 110, and the height of the loop is lower than the height of the loop of the bonding wire 130. Therefore, FIG. 2 shows that the loop of the bonding wire has a total of three stages.

Reference numeral 140 denotes a heat dissipation member, which is made of aluminum. Reference numeral 150 denotes a wiring board, and a printed board is used in this embodiment. A driving IC portion is mounted on the left side of the wiring board 150, and is electrically connected to the silicon substrate 100 provided with the electrothermal converter and the electric wiring by the bonding wire 130. Reference numeral 160 denotes a wiring conductor of the wiring board 150, and in particular, it is desirable that the wire bonding pad is plated with Au for wire bonding specifications. 180 is a solder resist covering the wiring of the wiring board 150. Reference numeral 190 is an adhesive layer for adhering the wiring board 150 and the heat dissipation member 140, and 200 is an adhesive layer for adhering the silicon substrate 100 and the heat dissipation member 140. Reference numeral 210 is a wiring pattern provided under the driving IC, and 220 is a solder resist covering the wiring pattern 210 provided under the driving IC. In addition, in FIG. 2, the display of the ink flow path is omitted.

Therefore, according to the present embodiment, the driving IC is mounted on the solder resist 220 on the wiring substrate 150 with an adhesive, and the driving IC 120, the electrothermal converter and the electric wiring are provided. Further, a wiring pattern with the silicon substrate 100 is provided on the wiring board 150, which is used as a common power supply pattern. A bonding wire 135 is provided between the common electrode of the electrothermal converter at each discharge port of the silicon substrate 100 and the common power source pattern on the printed wiring board.
Segment wiring of electrothermal converter at each outlet and driving IC
A wire bonding 130 connects the space and the space.
As a result, the segment wiring of the electrothermal converter of each discharge port and the common electrode wiring on the silicon substrate having the heat converter and the electrical wiring do not have to be formed in two layers, and can be formed in one layer. It was Therefore, it is possible to reduce the thin film forming process and the thin film photolithography process for forming the silicon substrate provided with the electrothermal converter and the electric wiring, and thus it is possible to provide an inexpensive inkjet recording head.

Further, in the case of the present embodiment, by providing a wiring pattern under the driving IC, for example, when a plurality of driving ICs are mounted, the signal wiring portion between the driving ICs is arranged under the driving IC. By doing so, it is possible to make the wiring board small and to provide an inexpensive ink jet recording head.

Next, an embodiment of a printer (IJRA) using the ink jet recording head of the present invention as an ink jet head cartridge will be described with reference to FIG. In the embodiment of FIG. 3, an inkjet head cartridge in which an inkjet recording head and an ink tank are integrated is used. Here, the carriage HC is engaged with the spiral groove 5004 of the lead screw 5005 that rotates via the driving force transmission gears 5011 and 5009 in association with the forward and reverse rotation of the drive motor 5013. The carriage HC has a pin (not shown). Have, arrow a,
It is reciprocated in the b direction. A recording head unit 5025 and an ink tank unit 5026 are mounted on the carriage HC.
A paper pressing plate 5002 presses the paper against the platen 5000 in the moving direction of the carriage. 500
Reference numeral 7,5008 denotes a photo coupler, which is a home position detecting means for confirming the presence of the lever 5006 of the carriage in this area and switching the rotation direction of the motor 5013.

Reference numeral 5016 is a member for supporting a cap member 5022 that caps both sides of the recording head, and 5015 is a suction means for sucking the inside of the cap member 5022, and suction recovery of the recording head is performed through the opening 5023. Perform. 5017 is a cleaning blade, 50
Reference numeral 19 denotes a member that allows the blade to move in the front-rear direction, and these members are supported by the main body support plate 5018.
Needless to say, a well-known cleaning blade can be applied to this example instead of this form. Also, 5
Reference numeral 012 denotes a lever for starting suction for suction recovery, which moves in accordance with the movement of the cam 5020 that engages with the carriage, and the driving force from the driving motor is movement-controlled by a known transmission means such as clutch switching. It

The capping, cleaning, and suction recovery are configured so that the desired processing can be performed at their corresponding positions by the action of the lead screw 5005 when the carriage HC is positioned in the home position side area. As long as a desired operation is performed at a known timing, any of the above can be applied to this example. Needless to say, the present example is applicable not only to the above example but also to an ink jet head cartridge in which the recording head and the ink tank can be separated.

The present invention is provided with means (for example, an electrothermal converter or a laser beam) that generates thermal energy as energy used for ejecting ink, particularly in the ink jet recording system, and the thermal energy The present invention provides excellent effects in a recording head and a recording device of the type that vigorously changes the state of ink. For the typical configuration and principle thereof, see, for example, US Pat.
What is carried out using the basic principle disclosed in the specification No. 723129 and the specification No. 4740796 is preferable. This method can be applied to both the so-called on-demand type and the continuous type. In particular, in the case of the on-demand type, it is arranged corresponding to the sheet or liquid path holding the liquid (ink). By applying at least one drive signal to the electrothermal converter, which corresponds to the recorded information and causes a rapid temperature rise exceeding nucleate boiling, thermal energy is generated in the electrothermal converter, and a recording head is produced. This is effective because the film is boiled on the heat-acting surface, and as a result, bubbles can be formed in the liquid (ink) in one-to-one correspondence with this drive signal. The liquid (ink) is ejected through the ejection openings by the growth and contraction of the bubbles to form at least one droplet. If this drive signal has a pulse shape,
Since the growth and shrinkage of the bubbles are immediately and appropriately performed, it is more preferable that the liquid (ink) having excellent responsiveness can be ejected. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. It should be noted that US Pat. No. 4,313 of the invention relating to the rate of temperature rise of the heat acting surface
If the conditions described in the specification No. 124 are adopted, more excellent recording can be performed. As the configuration of the recording head, in addition to the combination configuration of the ejection port, the liquid passage, and the electrothermal converter (the straight liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned specifications, the heat acting portion is also provided. U.S. Pat. No. 4,585,3, which discloses a configuration in which the core is located in the region of flexion.
The present invention also includes configurations using the specification No. 33 and the specification of US Pat. No. 4,459,600. In addition, for a plurality of electrothermal converters, a configuration in which a common slit is used as a discharge portion of the electrothermal converters is disclosed in JP-A-59-12.
Japanese Patent No. 3670 and Japanese Patent Laid-Open No. 1959/1984 which discloses a structure in which an opening for absorbing a pressure wave of thermal energy is made to correspond to a discharge portion.
The present invention is also effective as a configuration based on Japanese Patent No. 38461.

In addition, by being mounted on the apparatus main body, it can be electrically connected to the mounting main body and ink can be supplied from the apparatus main body on a replaceable chip type recording head or the recording head itself. The present invention is also effective when a cartridge-type recording head that is specially provided is used.

Further, it is preferable to add recovery means, preliminary auxiliary means, etc. to the recording head provided as a constitution of the recording apparatus of the present invention because the effects of the present invention can be further stabilized. Specifically, these are preheated by a capping means, a cleaning means, a pressure or suction means, an electrothermal converter, or a heating element other than this, or a combination thereof for the recording head. It is also effective to perform stable recording by performing a preliminary discharge mode in which discharge is performed separately from the means and the recording.

Further, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but the recording head may be integrally formed or a plurality of combinations may be used. The present invention is extremely effective for an apparatus provided with at least one of full colors by color mixing.

[0027]

According to the present invention, the wiring board is arranged adjacent to the silicon substrate provided with the electrothermal converter, and the driving IC mounted on the connection board is mounted on the wiring board.
Of the connection terminals, the connection terminal to be connected to the silicon substrate side is led out to the silicon substrate side on the connection substrate and connected to the silicon substrate with the bonding wire, without making the length of the bonding wire too long. Since the shape of the wiring board is not changed, the production yield is not reduced and the wiring on the silicon substrate is
Since there is no layer, there is an effect that the ink jet recording head can be manufactured at a lower cost. Further, by providing a wiring pattern under the driving IC, for example, when a plurality of driving ICs are mounted, the driving IC
It is possible to connect the signal wiring portion between them under the driving IC, to make the wiring board small, and to provide an inexpensive inkjet recording head.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of an inkjet recording head of the present invention.

FIG. 2 is a sectional view showing a second embodiment of the present invention.

FIG. 3 is a printer using the inkjet recording head of FIG. 1 as an inkjet head cartridge (IJ
It is a figure which shows one Example of RA).

[Explanation of symbols]

100 Silicone Substrate with Electrothermal Converter and Electric Wiring 110 Discharge Port and Common Liquid Chamber Forming Member 120 Driver IC for Driving 130 Bonding Wire 135 Bonding Wire 140 Heat Dissipating Member 150 Printed Circuit Board 160 Wire Bonding Pad 180 Wiring is Covered Solder resist 190 Adhesive layer between wiring board and heat dissipation member 200 Adhesive layer between silicon substrate and heat dissipation member 210 Wiring pattern provided under drive IC 220 Solder resist provided under drive IC

Claims (3)

[Claims] 1. An electrothermal converter that generates ejection energy for ejecting ink held in a common liquid chamber from an ejection port, and a first line connected to a power supply line to the electrothermal converter.
In an ink jet recording head in which a silicon substrate having a connecting electrode and a wiring substrate that carries wiring to the silicon substrate are closely fixed to each other on a heat dissipation member, the wiring substrate is provided on the silicon substrate side. Is provided with a second connection electrode connected to the wiring of the wiring board and connected to the first connection electrode, and a drive member for driving the electrothermal converter is mounted on the connection board. Is fixed on the wiring board in the vicinity of the silicon substrate, and the connection terminal to be connected to the electrothermal converter among the connection terminals of the driving member is a wiring pattern of the connection board. It is led out to a third connection electrode provided on the silicon substrate side, and the connection between the first connection electrode of the silicon substrate and the second connection electrode of the wiring board and the silicon An ink jet recording head, wherein the first connecting electrode of the substrate and the third connecting electrode of the connecting substrate are directly connected by a conductive member. 2. The ink jet recording head according to claim 1, wherein the drive member is a drive IC, and wiring is also provided on the connection substrate at a position corresponding to the bottom of the drive IC. 3. An image forming member for ejecting ink to form a desired image, and an ink storing member for storing ink ejected from the image forming member, which are mounted in a state of being connected to each other. Inkjet recording apparatus having a removable mounting portion and a transporting unit that transports a recording target member so that the mounting unit moves relative to a non-recording member to achieve a desired image formation, wherein the image forming member is An inkjet recording apparatus comprising the inkjet recording head according to claim 1.