JP2792706B2 - Printhead, printhead substrate, and inkjet printing apparatus - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording head of a recording apparatus used for a copying machine, a facsimile, a word processor, a printer as an output terminal of a host computer, a video output printer, and the like, and the head. Head and ink jet recording apparatus, in particular, a recording head in which an electrothermal conversion element for generating thermal energy used as recording energy and a recording functional element are formed on the same substrate, the head substrate and the ink jet recording apparatus About.

2. Description of the Related Art Conventionally, the configuration of a recording head is such that an electrothermal transducer array is formed on a single-crystal silicon substrate, and a transistor array, a drive circuit for the electrothermal transducer is provided outside the silicon substrate.
An electrothermal transducer driving functional element such as a diode array is arranged, and the connection between the electrothermal transducer and the functional element such as a transistor array is made by a flexible cable or wire bonding.

Japanese Patent Application Laid-Open No. 57-72867 aims to simplify the structure considered for the above-described head configuration, or to reduce defects caused in the manufacturing process, and to further uniformize the characteristics of each element and improve reproducibility. There is known an ink jet recording head in which an electrothermal conversion element and a functional element as proposed in the publication are provided on the same substrate.

FIG. 9 is a schematic sectional view showing a part of the recording head having the above-described configuration. Reference numeral 901 denotes a semiconductor substrate made of single crystal silicon. Reference numeral 902 denotes a collector region of an N-type semiconductor, 903 denotes an ohmic contact region of an N-type semiconductor with a high impurity concentration, 904 denotes a base region of a P-type semiconductor, and 905 denotes an emitter region of a N-type semiconductor with a high impurity concentration. 920. 906 is a silicon oxide layer as a heat storage layer and an insulating layer, 907 is a hafnium boride (HfB ₂ ) layer as a heating resistor layer, 908 is an aluminum (Al) electrode, 909 is a silicon oxide layer as a protective layer, Thus, the base 930 for the recording head is formed. Here, 940 is the heating section. The top plate 910 cooperates with the base 930 to define a liquid passage 950.

[Problems to be Solved by the Invention] By the way, although the above-described structure is excellent, high-speed driving, which is strongly required in recent years for a recording apparatus,
There is still room for improvement to satisfy energy saving, high integration, low cost, and high reliability.

First of all, high performance recording heads must be provided at low cost in order to achieve commercial success. For this purpose, it is necessary to integrate the functional elements at a high density, to reduce the area of the chip serving as the substrate of the recording head, and to construct a low-cost recording head.

For this purpose, it is conceivable to reduce the size of functional elements such as diode transistors.

However, in the case of an ink jet recording head, a current of 200 to 400 mA has to flow in order to efficiently drive the electrothermal transducer disposed therein. 1) The current may be partially concentrated, and the current density in a certain portion may abnormally increase to break the junction.

(2) A high voltage is required to secure a current for driving, and the entire system must be changed.

(3) If the current density flowing through the junction exceeds a certain value, the current is saturated and a desired current may not be obtained.

And other problems.

An object of the present invention is to solve the above-mentioned technical problems and to provide a recording head capable of high-speed recording and high-resolution recording, a recording head substrate, and an ink jet recording apparatus.

Another object of the present invention is to provide a highly integrated and highly reliable print head and a print head substrate at a low price, thereby contributing to a low price of the ink jet printing apparatus.

[Means for Solving the Problems] The present invention aims to solve these problems,
Therefore, the present invention provides a liquid discharge unit having a discharge port for discharging ink, and an electric heat exchange element for generating heat energy used for discharging the ink supplied to the liquid discharge unit. And a substrate provided with a functional element electrically connected to the electric heat exchange element, wherein a junction area between an anode electrode and a cathode electrode of the functional element has a drive current of 200 mA or more. 5 when less than 300mA
× 10 ^-5 cm ² or more and 1 × 10 when 300 mA or more and less than 400 mA
^-4 cm ² or more.

The present invention also relates to a recording head substrate in which an electric heat exchange element for generating heat energy and a functional element electrically connected to the electric heat exchange element are provided on the same substrate. 5 when the junction area between the anode and cathode electrodes of the device is 200 mA or more and less than 300 mA
× 10 ^-5 cm ² or more and 1 × 10 when 300 mA or more and less than 400 mA
^-4 cm ² or more.

Furthermore, an ink jet recording apparatus according to the present invention includes the above-mentioned recording head, a unit for supplying ink to the recording head, and a unit for conveying a recording medium to a recording position of the recording head.

[Operation] In the present invention, by designing the above-mentioned junction area to be equal to or larger than the set value, it was possible to reduce the area of the entire functional element and solve the above-mentioned problem that arises in reducing the cost.
That is, it is possible to obtain a small drive current without variation without changing the conventional drive voltage. And
An inexpensive and high-reliability electrothermal conversion element and a liquid jet recording head incorporating a functional element can be obtained.

EXAMPLES Hereinafter, the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following examples, as long as the object of the present invention can be achieved.

First Embodiment First, connection between an electrothermal transducer and a diode as a functional element for driving the electrothermal transducer, and driving of the electrothermal transducer will be described.

FIG. 1A is a cross-sectional view schematically illustrating a wiring portion of a substrate according to the present embodiment, and FIG. 1B is an equivalent of one block including a predetermined number of electrothermal conversion elements and functional elements. It is a circuit diagram. In this embodiment, as will be described later with reference to FIG. 2B, the collector / base common electrode 12 corresponds to the anode of the diode, and the emitter electrode 13 corresponds to the cathode of the diode. And the electrothermal conversion elements (RH1, RH
At the time of driving 2), by applying a positive potential bias (V _H1 ) to the electrothermal transducer connected to the collector / base common electrode 12, the NPN transistor in the cell is turned on, and the bias current is increased by the collector current and the collector current. It flows out of the emitter electrode 13 as a base current.

As a result of the configuration in which the base and the collector are short-circuited as in this example, the rise and fall characteristics of the heat of the electrothermal conversion element are improved, the film boiling phenomenon occurs, and the controllability of the growth and shrinkage of the resulting bubbles is improved. Stable ink ejection could be performed. This is because, in an ink jet recording head that uses thermal energy, the characteristics of the transistor and the film boiling characteristics are deeply linked, and the switching characteristics are faster and the rising characteristics are better than expected because the accumulation of minority carriers in the transistors is small. It is thought that it is affecting. In addition, a relatively small parasitic effect, no variation between elements, and a stable drive current can be obtained. In the present embodiment, furthermore, by grounding the isolation electrode 14, it is possible to prevent charge from flowing into another adjacent cell and to prevent the problem of malfunction of other elements. I have.

In such a semiconductor device, the concentration of the N-type collector buried region 2 is set to 1 × 10 ¹⁹ cm ⁻³ or more, and the concentration of the base region 5 is set to 5 × 10 ^{14 to} 5 × 10 ⁷ cm ^−3. In addition, it is desirable that the area of the joint surface between the high-concentration base region 8 and the electrode be as small as possible. In this way, it is possible to prevent the occurrence of leakage current from the NPN transistor to GND via the P-type silicon substrate 1 and the isolation region.

The driving method of the recording head will be described in more detail.
FIG. 1 (a) shows only two semiconductor functional elements (cells), but in practice such elements are arranged in equal numbers corresponding to, for example, 128 electric heat exchange elements. They are electrically connected in a matrix so that they can be driven in blocks (see FIG. 1B).

Here, the driving of the electrothermal resistance elements RH1 and RH2 as two segments in the same group will be described.

To drive the electrothermal transducer RH1, first switch G
The group is selected by 1, and the electrothermal converter RH1 is selected by the switch S1, and the positive voltage V _H1 is applied. Then, the diode cell SH1 having the transistor configuration is positively biased, and the current flows out from the emitter electrode 13. Thus, the electrothermal transducer RH1 generates heat, and this thermal energy causes a state change in the liquid to generate bubbles and discharge the liquid from the discharge port.

Similarly, when driving the electrothermal transducer RH2, the switch G
1. The switch S2 is selectively turned on to drive the diode cell SH2 and supply current to the electrothermal converter.

At this time, the substrate 1 is grounded via the isolation regions 3, 4, and 9. As described above, since the isolation regions 3, 4, and 9 of each semiconductor element (cell) are grounded, malfunction due to electrical interference between the elements is prevented.

FIG. 2 (a) shows a recording head configured generally as described above. As shown in the drawing, such a head includes a plurality of discharge ports 500, a liquid path wall member 501 made of a photosensitive resin or the like for forming a liquid path communicating with the discharge ports, a top plate 502, and an ink supply port.
503. The liquid path wall member 501 and the top plate 502 can be integrated by using a resin mold material.

Next, the substrate and its wiring section will be described in more detail.

FIG. 2 (b) is a schematic cross-sectional view of the recording head substrate and its wiring portion according to the present embodiment, that is, FIG. 2 (a).
FIG. 7 is a sectional view taken along line EE ′ of FIG.

In the figure, 1 is a P-type silicon substrate, 2 is an N-type collector buried region for forming a functional element, 3 is a P-type isolation buried area for separating a functional element, 4 is an N-type epitaxial region, 5 is P-type base region for forming a functional element, 6 is a P-type isolation region for element isolation, 7 is an N-type collector region for forming a functional element, 8
Is a high-concentration P-type base region for forming the device, 9 is a high-concentration P-type isolation region for device isolation, 10 is an N-type emitter region for forming the device, and 11 is a device for forming the device. A high-concentration N-type collector region, 12 is a collector / base common electrode, 13 is an emitter electrode, and 14 is an isolation electrode. Here, the NPN transistor is formed,
2, 4, 7, and 11 collector regions are emitter region 10 and base region
5, 8 are formed so as to completely surround them. Further, a P-type isolation buried region,
Each cell is surrounded and electrically isolated by the type isolation region 7 and the high concentration P type isolation region.

The recording head 100 according to the present embodiment has a SiO ₂ film 101 formed by thermal oxidation on a substrate having the above-described driving unit, and a HfB film formed by a sputtering method on a heat storage layer 102 formed of a Si oxide film formed by a CVD method or a sputtering method. There is provided an electrothermal conversion element composed of a heating resistance layer 103 such as ₂ and an electrode 104 made of Al or the like by a vapor deposition method. The heating resistance layer 103 such as HfB ₂ is also provided between the collector / base common electrode 12 and the emitter electrode 13 and the wirings 202 and 201 such as Al.

The heat generating resistor layer, Pt in _{addition, Ta, ZrB 2, Ti-} W, Ni
−Cr, Ta−Al, Ta−Si, Ta−Mo, Ta−W, Ta−Cu, Ta−Ni, Ta−
Ni-Al, Ta-Mo-Ni, Ta-W-Ni, Ta-Si-Al, Ta-W-Al
-Ni, Ti-Si, W, Ti, Ti-N, Mo, Mo-Si, W-Si and the like. Furthermore, on the heating part 110 of the electrothermal transducer, SiO ₂
And a protective film 106 such as Ta.

Here, the SiO ₂ film forming the heat storage layer 102 is provided integrally with an interlayer insulating film between the lowermost wirings 12 and 14 of the drive unit and 201 and 202 as intermediate wirings.

Also, the protective layer 105 is similarly integrated with the interlayer insulating film between the wirings 201 and 202.

Next, the manufacturing process of the recording head according to the present embodiment will be described with reference to FIGS.

On the surface of a P-type silicon substrate 1 having an impurity concentration of about 1 × 10 ¹² to 10 ¹⁶ cm ⁻³ , a silicon oxide film of about 5000 to 20000 ° was formed.

The silicon oxide film of the portion where the collector buried region 2 of each cell was to be formed was removed by a photolithography process.

After forming the silicon oxide film, N-type impurities such as P and As are ion-implanted, and the N-type collector buried region 2 having an impurity concentration of 1 × 10 ¹⁹ cm ⁻³ or more is formed by thermal diffusion to 10 to 20 μm.
m was formed. At this time, the sheet resistance was set to a low resistance of 30Ω / □ or less.

Subsequently, after removing the oxide film in the region where the P-type isolation buried region 3 is to be formed and forming an oxide film of about 100 to 3000 °, ions of a P-type impurity such as B are ion-implanted and thermally diffused. The impurity concentration is 1 × 10 ¹⁷ to 10 ¹⁹ cm ^-3
A mold isolation buried region 3 was formed. (The third
(FIG. 1A) After removing the oxide film on the entire surface, an N-type epitaxial region 4 having an impurity concentration of about 1 × 10 ¹² to 10 ¹⁶ cm ^{−3 is formed} to a thickness of 5 to 20 μm.
A degree of epitaxial growth was performed. (FIG. 3 (b)) Next, a silicon oxide film of about 100 to 300 ° is formed on the surface of the N-type epitaxial region, a resist is applied, patterning is performed, and a region where the low concentration base region 5 is to be formed is formed. Only a P-type impurity was ion-implanted. After the removal of the resist, a low-concentration P-type base region 5 having an impurity concentration of 5 × 10 ^{14 to} 5 × 10 ¹⁷ cm ⁻³ was formed to 5 to 10 μm by thermal diffusion.

After removing the oxide film again and forming a silicon oxide film of about 1000 to 10000 degrees again, the oxide film in the region where the P-type isolation region 6 is to be formed is removed, and the BSG film is formed on the entire surface by CVD. Deposited, and by thermal diffusion, P
The P-type isolation region 6 having an impurity concentration of 1 × 10 ¹⁸ to 10 ²⁰ cm ⁻³ is reached so as to reach the P-type isolation buried region 3.
It was formed to about 10 μm. (FIG. 3 (c)) Here, it is also possible to form BBr ₃ as a diffusion source.

After removing the BSG film, a silicon oxide film of about 1000 to 10,000 Å is formed. Further, after removing the oxide film only in the region where the N-type collector region 7 is to be formed, P ⁺ ions are implanted by forming PSG. Then, an N-type collector region 7 was formed so as to reach the collector buried region 5 by thermal diffusion. The sheet resistance at this time was a low resistance of 10Ω / □ or less. The thickness of the region is about 10 μm, and the impurity concentration is 1 × 10 ¹⁸
1010 ²⁰ cm ⁻³ .

Subsequently, after removing the oxide film in the cell region, a silicon oxide film of 100 to 300 mm is formed, and resist patterning is performed.
P-type impurity ions were implanted only into the regions where the high concentration base region 8 and the high concentration isolation region 9 were to be formed. After removing the resist, the oxide film in the region where the N-type emitter region 10 and the high-concentration N-type collector region 11 are to be formed is removed, a PSG film is formed on the entire surface, and N ⁺ is implanted. A P-type base region 8, a high-concentration P-type isolation region 9, an N-type emitter region 10, and a high-concentration N-type collector region 11 were simultaneously formed. Each of the regions has a thickness of 1.0 μm or less and an impurity concentration of 1 × 10 ¹⁹ to 10 ²⁰ c
m ^-3 . (FIG. 3 (d)) Further, after the silicon oxide film 101 was formed, the silicon oxide film at the connection portion of the electrode was removed, Al and the like were deposited on the entire surface, and Al and the like other than the electrode region were removed. (FIG. 3 (d)) Then, an SiO ₂ film 102 serving as a heat storage layer and an interlayer insulating film was formed on the entire surface to a thickness of about 0.4 to 1.0 μm by a sputtering method. This SiO ₂ film may be formed by a CVD method.

Next, in order to make electrical connection, a part CH of the insulating film 102 above the emitter region and the base / collector region was opened by photolithography. (FIG. 3 (f)) Next, HfB ₂ as the heat generating resistance layer 103 was coated on the SiO ₂ film 102,
In order to make an electrical connection, about 1000 堆積 was deposited on the electrode above the emitter region and the electrode above the base / collector region and patterned. (FIG. 3 (g)) A pair of electrodes 104 of the electrothermal transducer, a cathode electrode wiring 201 and an anode electrode wiring 202 of the diode are further formed thereon.
A layer made of an Al material was deposited and patterned, and an electrothermal exchange element and other wiring were formed simultaneously. (FIG. 3 (h)) Thus, an electrical connection was obtained by interposing a layer made of the same material as the heating resistance layer 103 between the semiconductor region and the Al electrode.

Thereafter, an SiO ₂ film 105 as an insulating layer between the protective layer of the electrothermal transducer and the layer Al wiring was deposited by a sputtering method. (FIG. 3 (i)) Then, about 2000 Ta of Ta is deposited as a protective layer 106 for cavitation resistance on the upper portion of the heat generating portion of the electrothermal transducer.
A photosensitive polyimide was formed as a protective layer on other portions. (FIG. 3 (j)) A liquid path wall member for forming an ink ejection portion and a top plate 502 are disposed on the base having the electrothermal conversion element and the semiconductor element prepared as described above. A recording head having an ink passage formed therein was manufactured. (FIG. 3 (k)) In this case, HfB ₂ is interposed between the emitter and a part of the base-collector common electrode. However, since a short circuit at the shallowly formed emitter portion is particularly problematic, at least Any configuration may be used as long as a layer made of the same material as the heat generating resistance layer is interposed in this portion.

With respect to such a recording head, the electrothermal transducer was driven by a block, and recording and operation tests were performed. In the operation test, eight semiconductor diodes were connected to one segment, and a current of 300 mA (2.4 A in total) was supplied to each segment. However, the other semiconductor diodes did not malfunction and could discharge well.

The present invention can of course be applied to a transistor having a PNP junction structure.

(Experimental Example) In the present invention, a plurality of samples were formed of the ink jet recording head formed by the above-described manufacturing process and the thermal head using the diode formed by the above-described manufacturing process.

Emitter junction area is 5 × 10 ^-7 , 5 × 10 ^-6 , 8 × 10 ^-6 , 1 × 10
^-5 , 2 × 10 ^-5 , 3 × 10 ^-5 , 5 × 10 ^-5 , 7 × 10 ^-5 , 8 × 10 ^-5 , 9 × 1
0 ^-5 , 1 × 10 ^-4 , 2 × 10 ^-4 , 3 × 10 ^-4 , 5 × 10 ^-4 , 1 × 10 ^-3 , 5 × 10
^-3 (both in cm ² ) were used to fabricate substrates incorporating 16 types of diodes, and these were used to create an inkjet recording head with 64 ejection ports and a thermal head with 64 heating elements. Eight samples each were prepared, and ink-jet recording and thermal recording were performed continuously for one hour, and the variation of recording dots for each pixel was evaluated. The results are shown in the following table.

As shown in the plan view of FIG. 3 (l) and the sectional view taken along the line AA '(m) of FIG. 3 (m), the area of the X portion having the emitter junction length Y (shaded line) Part), and the area of Z part (side part) is 10%
growing. In the table, "I / J" indicates an ink jet recording head, and "thermal" indicates a thermal head.

The evaluation method was to select the most distant dots among all the dots adhered to the recording paper and ejected from one ejection port, and passed those whose values were within the desired reference value, and deviated from the reference value. The nozzles were rejected. Out of the eight heads, all the ejection ports passed, ◎. If one of the ejection ports failed two or less, ○. , 6
The case where the number was more than or equal to X was evaluated. Basically, in the thermal head, since the thermal recording paper and the head come into contact with each other to develop color, no dot variation was observed. Here, "x" indicates an abnormal state such as no color development. Here, from the comparison with the thermal head, it can be seen that the I / J does not simply deteriorate the recorded image due to breakage of the diode or the like, but affects the ink ejection characteristics.

(Embodiment of Apparatus to which Printing Head is Applied) FIGS. 4 to 8 show an inkjet unit IJU, which is suitable for implementing or applying the printing head having the above configuration.
Inkjet head IJH, ink tank IT, inkjet cartridge IJC, inkjet recording device main unit IJR
FIG. 3 is an explanatory diagram for explaining each of A and a carriage HC and a relationship between them. Hereinafter, the configuration of each unit will be described with reference to these drawings.

As is apparent from the perspective view of FIG. 5, the ink-jet cartridge IJC in this example has a large ink storage ratio, and the tip of the ink-jet unit IJU is slightly larger than the front surface of the ink tank IT. It has a protruding shape. This inkjet cartridge IJC
The carriage HC is fixedly supported by positioning means and electrical contacts of a carriage HC (FIG. 8) mounted on the ink jet recording apparatus main body IJRA, which will be described later.
It is a disposable type that can be attached to and detached from HC.
FIGS. 4 to 8 show configurations to which various inventions made at the stage of establishment of the present invention are applied. Therefore, the entire configuration will be described while briefly describing these configurations. To

(I) Description of Inkjet Unit IJU The inkjet unit IJU is a bubble-jet type unit that performs recording using an electrothermal converter that generates thermal energy for causing ink to cause film boiling in response to an electric signal. is there.

In FIG. 4, reference numeral 100 denotes a structure in which a plurality of electrothermal transducers (discharge heaters) arranged on a Si substrate and electric wires such as Al for supplying electric power are formed by a film forming technique. It is a heater board having the above configuration. 1200 is heater board 10
A wiring board corresponding to the wiring of the heater board 100 (for example, connected by wire bonding), and a pad 1201 located at an end of the wiring and receiving an electric signal from the main unit. I have.

Reference numeral 1300 denotes a grooved top plate provided with a partition wall for partitioning a plurality of ink flow paths, a common liquid chamber, and the like. The ink receiving port 1500 receives ink supplied from the ink tank and introduces the ink into the common liquid chamber. Orifice plate 40 with multiple outlets
0 is integrally molded. Polysulfone is preferred as these integral molding materials, but other molding resin materials may be used.

Reference numeral 300 denotes, for example, a metal support that supports the back surface of the wiring board 1200 on a flat surface, and serves as a bottom plate of the ink jet unit. Reference numeral 500 denotes an M-shaped pressing spring, which presses the common liquid chamber at the center of the M-shape and presses a part of the liquid path at the front droop portion 501 with linear pressure. The foot of the spring pressing the heater board 100 and the top plate 1300 passes through the hole 3121 of the support 300,
By interlocking them with each other in a state sandwiching them, the heater board 100 and the top plate 1300 are pressed and fixed by the urging force of the pressing spring 500 and the front drooping portion 501 thereof. In addition, the support 300 is the ink tank IT 2
In addition to the three positioning protrusions 1012 and the positioning holes 312, 1900, and 2000 that engage with the positioning and heat fusion holding protrusions 1800 and 1801, the positioning protrusions 2500 and 2600 for the carriage HC of the apparatus main body IJRA are provided on the back surface. Has on the side. In addition, the support 300 also has a hole 320 that can penetrate an ink supply pipe 2200 (described later) that allows ink to be supplied from the ink tank. Attachment of the wiring board 200 to the support 300,
It is performed by sticking with an adhesive or the like. Incidentally, the concave portion 240 of the support 300
0,2400 are provided in the vicinity of the positioning projections 2500,2600, respectively. In the assembled ink jet cartridge IJC (FIG. 5), three peripheral sides thereof are formed in parallel grooves 3
It is located at an extension point of the head tip area formed by a plurality of 000,3001 so that unnecessary substances such as dust and ink do not reach the projections 2500 and 2600. This parallel groove 3000 is formed. As shown in FIG. 4, the lid member 800 forms an outer wall of the ink jet cartridge IJC and also forms a space for accommodating the ink jet unit IJU. Further, the ink supply member 600 in which the parallel groove 3001 is formed forms an ink conduit 1600 continuous with the above-described ink supply tube 2200 as a cantilever with the supply tube 2200 side fixed, and the ink supply tube 2200 is fixed to the fixed side of the ink conduit. A sealing pin 602 for ensuring capillary action with the supply pipe 2200 is inserted. Incidentally, reference numeral 601 denotes packing for sealing the ink tank IT and the supply pipe 2200, and 700 denotes a filter provided at the tank side end of the supply pipe.

Since the ink supply member 600 is molded, it is not only inexpensive, has high positional accuracy, and does not eliminate the deterioration in manufacturing accuracy, but also cantilever the conduit 1600 during mass production by the cantilever conduit 1600. Ink port 1500
Can be stabilized. In this example, a complete communication state can be reliably obtained only by pouring the sealing adhesive from the ink supply member side under the pressure contact state. The fixing of the ink supply member 600 to the support 300 is performed by fixing the ink supply member 60 to the holes 1901 and 1902 of the support 300.
This can be easily performed by making a back side pin (not shown) of No. 0 penetrate and project through the holes 1901 and 1902 of the support body 300 and heat-fusing a portion of the support body 300 protruding to the back side. The slightly protruding area of the heat-sealed rear part is the ink tank IT
The ink jet unit IJU is placed in a recess (not shown) in the side wall surface of the ink jet unit IJU, so that the positioning surface of the unit IJU can be obtained accurately.

(Ii) Explanation of the configuration of the ink tank IT The ink tank is sealed after inserting the cartridge body 1000, the ink absorber 900, and the ink absorber 900 from the side of the cartridge body 1000 opposite to the unit IJU mounting surface. And a lid member 1100 for stopping.

Reference numeral 900 denotes an absorber for impregnating the ink, and is arranged in the cartridge main body 1000. 1220 is the above parts 100
And a supply port for supplying ink to a unit IJU consisting of ~ 600, and by injecting ink from the supply port 1220 in a step before arranging the unit in the portion 1010 of the cartridge body 1000, the absorber 900 It is also an inlet for impregnating the ink.

In this example, the portions that can supply ink are the air communication port and this supply port, but the rib 2300 in the main body 1000 and the lid member for performing good ink supply from the ink absorber.
Since the tank air presence area formed by the partial ribs 2500 and 2400 of 1100 is formed over the corner area farthest from the ink supply port 1200 by communicating from the atmosphere communication port 1401 side, It is important that ink is supplied to the absorber relatively well and uniformly from the supply port 1200 side. This method is extremely effective in practice. The rib 1000 has four ribs parallel to the carriage moving direction on the rear surface of the main body 1000 of the ink tank, and prevents the absorber from adhering to the rear surface. Also, the partial ribs 2400 and 2500 are similarly provided on the inner surface of the lid member 1100 which is on an extension corresponding to the rib 1000, but unlike the rib 1000, they are in a divided state and the presence of air The space is larger than the former. In addition, partial rib
2500 and 2400 are distributed over less than half of the total area of the member 1000. With these ribs, the capillary force could be reliably guided to the supply port 1200 side while stabilizing the ink in the corner area farthest from the tank supply port 1200 of the ink absorber. Reference numeral 1401 denotes an atmosphere communication port provided in the lid member for communicating the inside of the cartridge with the atmosphere. 1400
Is a liquid-repellent material disposed inside the air communication port 1401, thereby preventing ink from leaking from the air communication port 1400.

The above-described arrangement of the ribs is particularly effective because the ink storage space of the above-described ink tank IT has a rectangular shape and has the long side on the side surface, but has a long side in the moving direction of the carriage. Case or cube, lid member
Providing ribs on the entire surface of 1100 can stabilize ink supply from ink absorber 900.

The structure of the mounting surface of the unit IJU of the ink tank IT is shown in FIG. A straight line that passes through the center of the orifice plate 400 and is substantially parallel to the mounting reference surface on the bottom surface of the tank IT or the surface of the carriage L ₁
When, two positioning protrusion 1012 engages the bore 312 of the support 300 is on the straight line L _1. The height of the protrusion 1012 is slightly lower than the thickness of the support 300, and the support 300 is positioned. On the extension of the straight line L ₁ on this drawing, pawl 2100 engagement surface 4002 of the 90 ° angle of the positioning hook 4001 of the carriage is engaged has a position, acting force the straight line L of the positioning relative to the carriage It is configured to operate in a plane area parallel to the reference plane including ₁ . As will be described later with reference to FIG. 4, these relationships are effective because the positioning accuracy of only the ink tank is equivalent to the positioning accuracy of the ejection port of the head.

Also, a fixing hole 190 for fixing the support 300 to the side of the ink tank is provided.
Ink tank projections 1800,180 corresponding to 0,2000 respectively
Reference numeral 1 denotes a portion longer than the above-mentioned protrusion 1012 and for fixing the support 300 to the side surface thereof by heat-welding a portion projecting through the support 300. This projection is perpendicular to the line L ₁ of the aforementioned 1800
When the straight line passing through is L ₃ and the straight line passing through the projection 1801 is L ₂ ,
Since on the straight line L ₃ are located substantially center of the supply port 1200, and the effect of stabilizing the state of bonding between the supply pipe 2200 and a mouth 1200 of the supply part, dropping or by the impact of these to the binding state This is a preferable configuration because the load can be reduced. Also,
The straight lines L ₂ and L ₃ do not coincide with each other, and the protrusion on the ejection port side of the head IJH is raised.
Since the projections 1800 and 1801 exist around 1012, the effect of reinforcing the positioning of the head IJH with respect to the tank is further produced. Incidentally, the curve indicated by L ₄ represents an ink supply member 600
Is the outer wall position at the time of mounting. The projections 1800 and 1801 have the curve L
Since it is along ₄ , sufficient strength and positional accuracy are given to the weight of the tip side configuration of the head IJH. Reference numeral 2700 denotes a tip flange of the ink tank IT, which is inserted into a hole of the front plate 4000 of the carriage and provided for an abnormal time when the displacement of the ink tank becomes extremely bad. Reference numeral 2101 denotes an engagement portion between the carriage HC and a further positioning portion.

After the ink tank IT is mounted with the unit IJU, the lid 8
Although the unit IJU is surrounded by excluding the lower opening by covering with the 00, the lower opening for mounting on the carriage HC for the ink jet cartridge IJC is close to the carriage HC. It forms an enclosed space. Therefore, the head IJH in this enclosed space
Although the heat generated from this is effective as a heat retaining space in this space, the temperature rises slightly for long-term continuous use. For this reason, in this example, a slit 1700 with a width smaller than this space is provided on the upper surface of the cartridge IJC to help the heat dissipation of the support, and the uniform temperature distribution of the entire unit IJU while preventing the temperature rise Was made independent of the environment.

When assembled as an inkjet cartridge IJC, the ink is supplied from the inside of the cartridge to the supply port 1200,
After being supplied into the supply tank 600 through the hole 320 provided in the 300 and the introduction port provided on the inside and back side of the supply tank 600, and passing through the inside thereof, an appropriate supply pipe and
It flows into the common liquid chamber via the ink inlet 1500 of 0. A packing made of, for example, silicone rubber or butyl rubber is provided at the connection portion for ink communication as described above, whereby sealing is performed to secure an ink supply path.

In this embodiment, the top plate 1300 is made of a resin such as polysulfone, polyethersulfone, polyphenylene oxide, or polypropylene having excellent ink resistance.
Together with the orifice plate part 400, it is integrally molded in a mold.

As described above, the integrally molded component is an ink supply member 600,
Integrated top plate and orifice plate, ink tank body 1000
As a result, not only the assembling accuracy becomes high, but also it is extremely effective in improving the quality of mass production. Further, since the number of parts can be reduced as compared with the conventional case, excellent desired characteristics can be surely exhibited.

(Iii) Attachment explanation of the ink jet cartridge IJC to the carriage HC In FIG. 7, reference numeral 5000 denotes a platen roller for guiding the recording medium P upward from below the sheet. The carriage HC moves along the platen roller 3000. The front surface 4000 of the inkjet cartridge IJC (2 mm thick) is located on the front platen side of the carriage and the pad 201 of the wiring board 200 of the cartridge IJC. Corresponding pad 2011
Support plate 4003 for holding a flexible sheet 4005 provided with a rubber pad 4006 for generating an elastic force for pressing the flexible sheet 4005 against each pad 2011 from the back side.
And a positioning hook 4001 for fixing the inkjet cartridge IJC to the recording position.
The front plate 4000 has two positioning projections 410 corresponding to the positioning projections 2500 and 2600 of the support 300 of the cartridge, respectively.
Receive a vertical force towards. For this reason, the reinforcing rib has a plurality of ribs (not shown) on the platen roller side of the front plate that are oriented in the direction of the vertical force. The ribs are slightly (approximately than the front position L ₅ when the cartridge IJC mounted
(Approximately 0.1 mm) Also formed is a head protection projection projecting toward the platen roller. Support plate for electrical connection 4003
Has a plurality of reinforcing ribs 4004 not in the direction of the ribs but in the vertical direction, and the proportion of protrusion from the platen side toward the hook 4001 side is reduced. This also has the function of inclining the position at the time of mounting the cartridge as shown in the figure. The support plate 4003 has a positioning surface 4008 on the platen side and a positioning surface 4007 on the hook side to stabilize the electrical contact state. Rubber sheet 40
Define the amount of deformation of 06 uniquely. These positioning surfaces are in contact with the surface of the wiring board 300 when the cartridge IJC is fixed at a recordable position. In this example, since the are distributed so as to further be symmetrical with respect to a line L ₁ that the pad 201 described above of the wiring board 300, the rubber sheet
The contact pressure of the pads 2011 and 201 is further stabilized by equalizing the amount of deformation of each of the bolts 4006. The distribution of the pads 201 in this example is two rows above and two rows below and two rows vertically.

The hook 4001 has a long hole that engages with the fixed shaft 4009, and after rotating counterclockwise from the position shown in the drawing using the moving space of the long hole, moves to the left along the platen roller 5000. By moving, the inkjet cartridge IJC is positioned with respect to the carriage HC. The hook 4001 can be moved in any manner, but is preferably configured to be moved by a lever or the like. In any case, when the hook 4001 rotates, the cartridge IJC moves to the platen roller side while the positioning projections 2500 and 2600 move to positions where the positioning protrusions 2500 and 2600 can abut the positioning surface 4010 of the front plate. While the 90 ° hook surface 4002 is in close contact with the 90 ° surface of the claw 2100 of the cartridge IJC, the cartridge IJC pivots in the horizontal plane around the contact area between the positioning surfaces 2500 and 4010 and finally the pads 201 and 20.
Contact of 11 comrades begins. And the hook 4001 is in the predetermined position,
That is, when held at the fixed position, the pads 201 and 2011 have complete contact with each other, the positioning surfaces 2500 and 4010 have complete contact with each other, the 90-degree surface 4002 and the two-side contact between the 90-degree surface of the claw, and the wiring board. 30
0 and surface contact between the positioning surfaces 4007 and 4008 are simultaneously formed, and the holding of the cartridge IJC with respect to the carriage is completed.

(Iv) Schematic description of the apparatus main body FIG. 8 shows an ink jet recording apparatus to which the present invention can be applied.
In the outline view of IJRA, the carriage that engages with the lead groove 5004 of the lead screw 5005 that rotates through the driving force transmission gears 50111 and 5009 in conjunction with the forward and reverse rotation of the drive motor 5013
The HC has a pin (not shown) and is reciprocated in the directions of arrows a and b. Reference numeral 5002 denotes a paper pressing plate, which presses paper against the platen 5000 in the carriage movement direction. 5007,5008
Is a home position detecting means for confirming the presence of the lever 5006 of the carriage in this area by a photocoupler and switching the rotation direction of the motor 5013. Reference numeral 5016 denotes a member for supporting a cap member 5022 for capping the front surface of the recording head. Reference numeral 5015 denotes suction means for suctioning the inside of the cap, and performs suction recovery of the recording head through the opening 5023 in the cap.
5017 is a cleaning blade, 5019 is a member that can move this blade in the front-rear direction, and a main body support plate 5018.
These are supported. It goes without saying that the blade is not limited to this form, and a well-known cleaning blade can be applied to this embodiment. Reference numeral 5012 denotes a lever for starting suction for suction recovery, and a cam 5020 which engages with the carriage.
The driving force from the driving motor is controlled by known transmission means such as clutch switching.

These capping, cleaning and suction recovery
When the carriage comes to the home position side area, it is configured to perform desired processing at the corresponding position by the action of the lead screw 5005, but if the desired operation is performed at a known timing, Either can be applied to this example. Each of the configurations described above is an excellent invention when viewed alone or in combination, and shows preferred configuration examples for the present invention.

(Others) The present invention brings about an excellent effect particularly in a recording head and a recording apparatus of a bubble jet system among ink jet recording systems. This is because, according to such a method, the recording density is increased and the definition is advanced, and the above-described problem may occur.

As for the representative configuration and principle, it is preferable to use the basic principle disclosed in, for example, US Pat. Nos. 4,723,129 and 4,740,796. 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 a sheet or a liquid path holding a liquid (ink). Applying at least one drive signal corresponding to the recording information and giving a rapid temperature rise exceeding the boiling point to the electrothermal transducer, thereby causing the electrothermal transducer to generate thermal energy, and This is effective because a film in the liquid (ink) corresponding to the driving signal can be formed one by one by causing film boiling on the heat acting surface. The liquid (ink) is ejected through the ejection opening by the growth and contraction of the bubble to form at least one droplet. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. U.S. Pat. No. 44
Those described in JP-A-63359 and JP-A-4345262 are suitable. Further, when the conditions described in US Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

As a configuration of the recording head, in addition to a combination configuration (a linear liquid flow path or a right-angled liquid flow path) of a discharge port, a liquid path, and an electrothermal converter as disclosed in the above-mentioned specifications, A configuration using U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459,600, which disclose a configuration in which is disposed in a bending region, is also included in the present invention. In addition, Japanese Unexamined Patent Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy is provided. The effect of the present invention is effective even if the configuration is based on JP-A-59-138461, which discloses a configuration corresponding to a discharge unit. That is, recording can be performed reliably and efficiently regardless of the form of the recording head.

Further, the present invention can be effectively applied to a full-line type recording head having a length corresponding to the maximum width of a recording medium on which a recording apparatus can record. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads, or a configuration as one integrally formed recording head. In addition, even in the case of the serial type as described above, a replaceable chip-type recording head that can be electrically connected to the apparatus main body and supplied with ink from the apparatus main body by being attached to the apparatus main body. The present invention is also effective when a cartridge-type recording head provided integrally with the recording head itself as shown in FIGS. 4 to 8 is used.

Further, it is preferable to add recovery means for the print head, preliminary auxiliary means, and the like provided as a configuration of the printing apparatus in the present invention since the effects of the present invention can be further stabilized. If these are specifically mentioned, capping means for the recording head, cleaning means, pressurizing or suction means, preheating means using an electrothermal transducer or another heating element or a combination thereof, Performing a preliminary ejection mode in which ejection is performed separately from printing is also effective for performing stable printing.

Regarding the type or number of print heads to be mounted, for example, in addition to one provided for single color ink, a plurality of print heads are provided corresponding to a plurality of inks having different print colors and densities. May be used.

In addition, as the form of the ink jet recording apparatus to which the present invention is applied, in addition to those used as image output terminals of information processing equipment such as a computer, a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmission / reception function It may take a form.

Further, the substrate according to the present invention can be applied not only to an ink jet recording head but also to a thermal head.

[Effects of the Invention] As described above, according to the present invention, it is possible to form a plurality of semiconductor elements having a high withstand voltage and excellent electrical isolation for each element on a single substrate. Therefore, for example, in a matrix-connected circuit, it is not necessary to separately externally attach the elements alone, and the number of steps can be reduced. Therefore, the number of failure points is reduced, and the high reliability of the obtained recording head is secured. be able to.

Further, according to the present invention, by defining the junction area and the junction length of the semiconductor element in flowing the N-type emitter, the characteristic variation is similarly small even if the semiconductor element is designed in any form. A semiconductor element with sufficient reliability can be obtained.

[Brief description of the drawings]

FIGS. 1A and 1B are a cross-sectional view and an equivalent circuit diagram schematically showing a wiring portion of a printhead substrate according to an embodiment of the present invention, and FIGS. 3B is a perspective view of a recording head according to an embodiment of the present invention, and a cross-sectional view taken along line EE ′. FIGS. 3A to 3K are manufacturing methods of the recording head according to the present embodiment. FIG. 3 (l) and (m) are schematic diagrams for explaining the emitter junction area, and FIG. 4 is a cartridge which can be configured by applying the recording head according to the present invention. 5, FIG. 5 is an assembled perspective view of FIG. 4, FIG. 6 is a perspective view of a mounting portion of the ink jet unit in FIG. 4, and FIG. 7 is an explanatory view of mounting the cartridge shown in FIG. FIG. 8 shows the cartridge shown in FIG. Device external view, FIG. 9 is a schematic sectional view of a conventional recording head. 1 ... P-type silicon substrate, 2 ... N-type collector buried region, 3 ... P-type isolation buried region, 4 ... N-type epitaxial region, 5 ... P-type base region, 6 ... P-type Isolation region 7 N-type collector region 8 High-concentration P-type base region 9 High-concentration P-type isolation region 10 N-type emitter region 11 High-concentration N-type collector region , 12: Common collector / base electrode, 13: Emitter electrode, 14: Isolation electrode, 100: Recording head substrate (heater board), 103: Heat generation resistance layer, 104: Electrode 105, 106: Protection Layer, 500 …… Discharge port.

Claims (3)

(57) [Claims] A liquid discharge section having a discharge port for discharging ink; an electrothermal conversion element for generating heat energy used for discharging ink supplied to the liquid discharge section; A substrate provided with a functional element electrically connected to the electrothermal transducer, wherein a junction area between an anode electrode and a cathode electrode of the functional element has a drive current of 200 mA or more to 300 mA. Less than 5 × 10 ^-5
In cm ² or more, the recording head is characterized in that it is 1 × 10 ^-4 cm ² or more when less than 300mA ~400mA. 2. A printhead substrate, wherein an electrothermal transducer for generating thermal energy and a functional element electrically connected to the electrothermal transducer are provided on the same substrate. 5 × 10 ⁻⁵ when the junction area between the anode electrode and the cathode electrode is 200 mA or more and less than 300 mA.
In cm ² or more, the recording head is characterized in that it is 1 × 10 ^-4 cm ² or more when less than 300mA ~400mA. 3. A recording head according to claim 1, further comprising: means for supplying ink to said head; and means for conveying a recording medium to a recording position of said recording head. Ink jet recording device.