Substrate for ink jet recording head, ink jet recording head, ink jet recording device, and manufacture of substrate for ink jet recording head and ink jet recording head

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Industrial application field]

The present invention relates to a method for manufacturing a substrate for an inkjet recording head and a method for manufacturing an inkjet recording head.

【0002】

[Explanation of background technology]

Conventionally, the configuration of the recording head is such that an electric heat conversion element array is formed on a single crystal silicon substrate, and a functional element for driving an electric heat conversion element such as a transistor array is arranged outside the silicon substrate as a drive circuit for the electric heat conversion element. , The connection between the electrothermal conversion element and the transistor array was made by a flexible cable, wired bonding, or the like.

【0003】

For the purpose of simplifying the structure considered for the above-mentioned recording head configuration, reducing defects caused in the manufacturing process, and improving the uniformity and reproducibility of the characteristics of each element, Japanese Patent Application Laid-Open No. 57-72867 An inkjet recording apparatus having a recording head in which an electrothermal conversion element and a functional element are provided on the same substrate as proposed in the publication is known.

【0004】

FIG. 20 is a cross-sectional view showing an example of the substrate of the recording head having the above-described configuration.

【0005】

Reference numeral 901 is a semiconductor substrate made of single crystal silicon. 902 is the collector region of the N-type semiconductor, 903 is the ohmic contact region of the N-type semiconductor with high impurity concentration, 904 is the base region of the P-type semiconductor, and 905 is the emitter region of the N-type semiconductor with high impurity concentration. Forming 920. 906 is an interlayer film composed of a heat storage layer and a silicon oxide layer as an interlayer insulating layer, 907 is a heat generation resistor layer, 908 is an aluminum (Al) electrode, and 909 is a protective layer composed of a silicon oxide layer. Base 930 is formed. Here, 910 is the heat generating part. A top plate and a liquid passage are formed on the substrate 930 to form a recording head.

【0006】

By the way, although the above-mentioned structure is excellent, it is still necessary to satisfy the high-speed drive, energy saving, high integration, low cost, and high reliability that are strongly required for recording devices in recent years. There is room for improvement.

【0007】

First of all, for commercial success, reliable recording heads must be offered at low prices. For that purpose, it was necessary to improve the exposed end of the resistor, which determines the life of the conventional recording head.

【0008】

That is, the conventional recording head has a heat generating portion shape as shown in FIG. 21 in which Al is isotropically removed when the wiring material of the electrode 908 made of Al or the like is removed by wet treatment. FIG. 21 is an enlarged view of the heat generating portion 910. If the Al electrode 908 is removed by dry etching such as RIE, the Al side surface will stand vertically. In this case, when the heating unit 910 is driven, a drive current flows by applying a voltage as shown in 801A and 801B in FIG. The current densities of the drive currents 801A and 801B are 8.2 × 10 at the exposed end A or B of the heat-generating resistor layer shown in FIG.⁷ A / cm² To reach. This value shows that the current density in the Al electrode 908 is 1.7 × 10.⁶ A / cm² , Current density 1.03 × 10 at the center C of the heating resistor layer 907⁷ A / cm² It is an abnormally large value compared to. It has been found that this concentration of current density at the exposed end A or B of the heating resistor layer cuts a part of the heating resistor layer 907, which determines the life of the recording head.

【0009】

Therefore, the present inventor is convinced that alleviating the concentration of the current density at the exposed end of the heat generating resistor layer 907 extends the life of the recording head and produces the uniformity of the recording head.

【0010】

In addition, since the end 940 of the conventional Al electrode 908 stands close to the vertical, the thickness of the interlayer film 906 and the protective film 909 must be about 1.25 μm and 1.0 μm, respectively, in order to improve the step coverage. Met.

【0011】

[Problems to be Solved by the Invention]

The conventional recording head described above has the following problems.

【0012】

In other words, the interlayer film 906 as thick as 1.25 μm significantly deteriorates the throughput of the device, which has been a bottleneck for cost reduction.

【0013】

In addition, the protective film 909 as thick as 1.0 μm is present as a thermal resistance when the heat generated in the heat generating portion 910 is transferred to the ink, and it is necessary to increase the driving power of the resistor, and the frequency characteristics deteriorate due to the thermal conduction delay. I was letting you.

【0014】

That is, because of this thick protective film 909, the performance and power consumption of the recording head have been lagging behind in the past.

【0015】

The present invention has been made in view of the problems of the above-mentioned conventional techniques, and it is possible to reduce the price and improve the reliability by maintaining the step coverage with the upper and lower layers and thinning the film. It is an object of the present invention to provide a substrate for an inkjet recording head, an inkjet recording head and an inkjet recording apparatus, and a method for manufacturing a substrate for an inkjet recording head and an inkjet recording head.

【0016】

[Means for solving problems]

The features of the present invention are the electric heat conversion element group, the functional element group for driving the electric heat conversion element that drives the electric heat conversion element of the electric heat conversion element group, and each of the functional element group by photolithography. In a method for manufacturing a substrate for an inkjet recording head in which a group of wiring electrodes for connecting a functional element and the electric heat conversion element are formed on a substrate, the connection end faces of the wiring electrodes of the group of wiring electrodes are connected to the wiring electrodes. A wiring electrode group etching process in which the material layer of the wiring electrode is etched while the mask photoresist is retreated by alternately using the etching solution for mask and the tri-methyl-ammonium hydroxide aqueous solution for etching. It is where you have it.

【0017】

Then, in the wiring electrode group etching step, it is preferable to simultaneously form the side surface together with the connection end face of each wiring electrode of the wiring electrode group.

【0018】

Further, the material of the wiring electrode may be aluminum.

【0019】

Another feature of the present invention is the electric heat conversion element group, the functional element group for driving the electric heat conversion element group for driving the electric heat conversion element group, and the functional element group by photoetching. A substrate making step of forming a substrate by forming a wiring electrode group for connecting each functional element of the group and the electric heat conversion element on the substrate, and an ink ejection having a plurality of ejection ports for ejecting ink. In a method of manufacturing an inkjet recording head including an ink ejection portion creating step of creating a portion on the substrate, the substrate creating step masks the connection end faces of each wiring electrode of the wiring electrode group with an etching solution for wiring electrodes. This includes a wiring electrode group etching step in which the material layer of the wiring electrode is etched while the masking photoresist is etched back by alternately using a tri-methyl-ammonium hydroxide aqueous solution for etching.

【0020】

In this case as well, it is preferable to simultaneously form the side surface together with the connection end face of each wiring electrode of the wiring electrode group in the wiring electrode group etching step, and the material of the wiring electrode may be aluminum.

【0021】

[Action]

According to the method for manufacturing an inkjet recording head of the present invention, it is possible to easily and highly accurately form a connection end face of a wiring electrode for connecting a functional element and an electric heat conversion element into a desired shape such as including a step. By making the electrothermal conversion element exhibit long life and uniform characteristics, improving the step coverage of the protective film, and making it possible to thin the protective film, it is possible to reduce power consumption and improve frequency response. It is possible.

【0022】

The inkjet recording head of the present invention uses the above-mentioned substrate for the inkjet recording head, and the protective film intervening as heat resistance when the heat generated by the electric heat conversion element is transferred to the ink can be thinned. It is possible to reduce the driving power of the electrothermal conversion element and improve the frequency characteristics.

【0023】

Since the inkjet recording apparatus of the present invention uses the above-mentioned inkjet recording head, it is possible to increase the speed of recording and reduce the power consumption.

【0024】

In the method for manufacturing an inkjet recording head substrate and an inkjet recording head of the present invention, the connection end faces of the wiring electrodes of the wiring electrode group are subjected to a tri-methyl ammonium hydrooxide for etching a wiring electrode etching solution and a mask photoresist. By etching the material layer of the wiring electrode while etching the photoresist of the mask by alternately using the aqueous solution, it is possible to easily and highly accurately form the desired shape such as including a step. As described above, it is possible to relax the current density concentration at the connection end and thin the protective film, reduce the driving power, and improve the frequency characteristics.

【0025】

[Example]

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

【0026】

FIG. 1 is a schematic cross-sectional view of a substrate 100 for an inkjet recording head formed on a substrate for a recording head according to the present invention.

【0027】

The substrate 100 of this embodiment has a functional element composed of NPN transistors having P-type base regions 5 and 8, N-type collector embedded regions 7 and N-type emitter regions 10 and 11, similar to the conventional ones described above. The mold silicon substrate 1 is covered with a heat storage layer 101 made of an oxide film or the like on which collector-base common electrodes 12, emitter electrodes 13 and isolation electrodes 14 which are wiring electrodes are formed, and a PCVD method or sputtering is performed on the upper layer. An interlayer film 102 made of a silicon oxide film or the like is formed by the method.

【0028】

Each of the electrodes 12, 13 and 14 is made of aluminum or the like, and as shown in FIGS. 2A and 2B, the end face and the side wall, that is, the entire side surface are formed in a stepped shape (14 is shown in the figure). Z). Since Al forming each of the electrodes 12, 13 and 14 has a step on the side surface, the step coverage of the interlayer film 102 is very excellent, and the interlayer film 102 does not lose the heat storage effect as compared with the conventional one. It can be formed thin. Further, in order to partially open the interlayer film 102 to electrically connect the collector-base common electrode 12, the emitter electrode 13 and the isolation electrode 14, and to electrically form wiring on the interlayer film 102. Wiring 104, which is a wiring electrode, such as Al of the above, is installed. That is, after partially opening the interlayer film 102, HfB by the sputtering method₂ A heat generating portion 110 which is an electric heat conversion element composed of a heat generating resistance layer 103 such as the above and a wiring 104 such as Al by a vapor deposition method or a sputtering method is provided.

【0029】

Enlarged views of the heat generating portion 110 are shown in FIGS. 3 (a) and 3 (b).

【0030】

Similar to the electrodes, the end face and the side wall in the longitudinal direction of the wiring 104 constituting the heat generating portion 110 are also formed in a stepped shape.

【0031】

The materials constituting the heat generation resistance layer 103 include Ta, ZrB.₂, Ti-W, Ni-Cr, Ta-Al, Ta-Si, Ta-Mo, Ta-W, Ta-Cu, Ta-Ni, Ta-Ni-Al, Ta-Mo-Al, Ta-Mo-Ni , Ta-W-Ni, Ta-Si-Al, Ta-W-Al-Ni, etc.

【0032】

Further, as shown in FIG. 1, SiO is placed on the heat generating portion 110 by a sputtering method or a CVD method.₂ , SiN, SiON and the like protective film 105 and Ta and the like protective film 106 are provided.

【0033】

Here, as described above, since the end face and the side wall of the wiring 104 are formed in a stepped shape, the coverage of the protective film 105 is extremely good, and the conventional film thickness of 10000 Å can be reduced to 6000 Å. It is possible to efficiently and at high speed transfer the heat generated by the heat generating unit 110. In addition, the throughput of the protective film deposition device could be doubled. Furthermore, as shown in FIG. 4, the concentration of the drive currents 401A and 401B at the end of the heat generation resistance layer 103 as described above is reduced to the conventional 8.2 × 10.⁷ A / cm² From 3.2 × 10⁷ A / cm² It can be reduced to, and the durability can be improved.

【0034】

Next, the basic operation of the functional element according to the above configuration will be described with reference to FIG.

【0035】

FIG. 5 is a schematic diagram for explaining a method of driving the heat generating portion 110 of the substrate 100 shown in FIG.

【0036】

In this embodiment, as shown in FIGS. 1 and 5, the collector-base common electrode 12 corresponds to the anode electrode of the diode, and the emitter electrode 13 corresponds to the cathode electrode of the diode. That is, a positive potential bias (V) is applied to the collector-base common electrode 12._H1) Turns on the NPN transistors in the cells (SH1, SH2), and the bias current flows out from the emitter electrode 13 as the collector current and the base current. Further, as a result of short-circuiting the base and the collector, the heat of the electric heat conversion element (RH1, RH2) corresponding to the heat generating portion 110 becomes good in the rising and falling characteristics, and the film boiling phenomenon occurs, and the bubbles accompanying the heat rise and fall. The controllability of growth and contraction was improved, and stable ink ejection could be performed. This is because the inkjet recording head that uses thermal energy has a deep connection between the transistor characteristics and the film boiling characteristics, and because the accumulation of minority carriers in the transistor is small, the switching characteristics are fast and the rise characteristics are better than expected. It is thought that it is affecting. In addition, there is relatively little parasitic effect, there is no variation between elements, and a stable drive current can be obtained.

【0037】

In this embodiment, further, by grounding the isolation electrode 14, it is possible to prevent the inflow of electric charge into other adjacent cells, and it is possible to prevent the problem of malfunction of other elements. There is.

【0038】

In such a semiconductor device, the concentration of the N-type collector embedded region 2 is 1 × 10.¹⁸cm^-3With the above, the concentration of P-type base region 5 is 5 × 10.¹⁴~5×10¹⁷cm^-3 Furthermore, it is desirable to make the area of the joint surface between the high-concentration base region 8 and the collector-base common electrode 12 as small as possible. In this way, it is possible to prevent the generation of leakage current from the NPN transistor through the P-type silicon substrate 1 and the isolation region to the ground.

【0039】

The driving method of the heat generating portion 110 will be described in more detail.

【0040】

Although FIG. 5 shows only two semiconductor functional elements (cells) SH1 and SH2, in reality, such functional elements have 128 electric heats corresponding to, for example, the heat generating portion 110. They are arranged at equal intervals corresponding to the conversion elements, and are electrically connected in a matrix so that the blocks can be driven. Here, for the sake of simplicity, the driving of the electrothermal conversion elements RH1 and RH2 as two segments in the same group will be described.

【0041】

In order to drive the electric heat conversion element RH1, the group is first selected by the switching signal G1 and the electric heat conversion element RH1 is selected by the switching signal S1. Then, the functional element cell SH1 having a transistor configuration is positively biased and a current is supplied, and the electric heat conversion element RH1 generates heat. This heat energy causes a state change in the liquid, generates bubbles, and discharges the liquid from the discharge port. Similarly, even when the electric heat conversion element RH2 is driven, the electric heat conversion element RH2 is selected by the switching signal G1 and the switching signal S2, the functional element cell SH2 is driven, and a current is supplied to the electric heat conversion element RH2.

【0042】

At this time, the P-type silicon substrate 1 is installed via the isolation regions 3, 6 and 9. By installing the isolation regions 3, 6 and 9 of each semiconductor functional element (cell) in this way, malfunction due to electrical interference between each semiconductor functional element is prevented.

【0043】

As shown in FIG. 6, the substrate 100 configured in this way has a liquid passage wall member 501 made of a photosensitive resin or the like for forming a liquid passage 505 communicating with a plurality of discharge ports 500, and an ink supply port 503. A top plate 502 is attached to form a recording head 600. In this recording head 600, the recording liquid injected from the ink supply port 503 is stored in the common liquid chamber 504 inside and supplied to each liquid passage 505, and in that state, the heat generating portion 110 is driven to drive the discharge port 500. The recording liquid is discharged from.

【0044】

Next, the manufacturing process of the recording head 600 according to this embodiment will be described with reference to FIGS. 7 to 15.

【0045】

(1) P-type silicon substrate 1 (impurity concentration 1 x 10)¹²~1×10¹⁶cm^-3After forming a silicon oxide film of about 8000 Å on the surface of the surface, the silicon oxide film of the portion forming the N-type collector embedding region 2 of each cell was removed by a photolithography step. After forming a silicon oxide film, N-type impurities (for example, P, As, etc.) are ion-implanted, and the impurity concentration is 1 × 10 by thermal diffusion.¹⁸cm^-3The above N-type collector embedded region 2 was formed with a thickness of about 2 to 6 μm so that the sheet resistance was as low as 30 Ω / port or less.

【0046】

Subsequently, the oxide film in the region where the P-type isolation embedded region 3 should be formed is removed to form an oxide film of about 1000, and then P-type impurities (for example, B) are ion-implanted and thermally diffused. Impurity concentration 1 × 10¹⁵~1×10¹⁷cm^-3The above P-type isolation embedded region 3 was formed (Fig. 7 above).

【0047】

(2) After removing the silicon oxide film on the entire surface, N-type epitaxial region 4 (impurity concentration 1 × 10)¹³~1×10¹⁵cm^-3(Approximately) was epitaxially grown to a thickness of about 5 to 20 μm (Fig. 8 above).

【0048】

(3) A silicon oxide film of about 1000 was formed on the surface of the N-type epitaxial region 4, a resist was applied, and patterning was performed, and P-type impurities were ion-implanted only in the portion where the low-concentration P-type base region 5 was formed. After removing the resist, heat diffusion causes a low concentration of P-type base region 5 (impurity concentration 1 × 10).¹⁴~1×10¹⁷cm^-3Approximately) was formed to a thickness of about 5 to 10 μm. After that, the oxide film is completely removed again to form a silicon oxide film of about 8000 Å, then the oxide film at the portion where the P-type isolation region 6 should be formed is removed, and the BSG film is deposited on the entire surface by the CVD method. Furthermore, the P-type isolation region 6 (impurity concentration 1 × 10) is reached so that it reaches the P-type isolation embedded region 3 by thermal diffusion.¹⁸~1×10²⁰cm^-3A thickness of about 10 μm was formed (Fig. 9 above). At this time, BBr₃ It is also possible to form a P-type isolation region 6 using the above as a diffusion source.

【0049】

(4) After removing the BSG film, forming a silicon oxide film of about 8000 Å, and further removing only the part where the N-type collector region 7 should be formed, N-type solid phase diffusion and phosphorus ion injection or thermal diffusion N-type collector region 7 with a thickness of 10 μm (impurity concentration 1 × 10) so that the sheet resistance reaches the N-type collector embedded region 2 and the sheet resistance is as low as 10 Ω / port or less.¹⁸~1×10²⁰cm^-3Degree) was formed.

【0050】

Subsequently, a silicon oxide film of about 12500 Å was formed to form a heat storage layer 101. Then, the oxide film in the cell region was selectively removed to form a silicon oxide film of about 2000 Å.

【0051】

Next, resist patterning was performed, and P-type impurities were injected only into the portions where the high-concentration base region 8 and the high-concentration P-type isolation region 9 should 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 should be formed is removed, a thermal oxide film is formed on the entire surface, N-type impurities are injected, and thermal diffusion is performed. N-type emitter region 10 and high-concentration N-type collector region 11 were formed at the same time. The thickness of the N-type emitter region 10 and the high-concentration N-type collector region 11 is 1.0 μm or less, and the impurity concentration is 1 × 10.¹⁸~1×10²⁰cm^-3It was set to a degree (Fig. 10 above).

【0052】

(5) Furthermore, after removing the silicon oxide film at the connection point of some electrodes, Al and the like were deposited on the entire surface as the material layer of the wiring electrode, and Al and the like other than the part of the electrode region were removed (Fig. 11 below). At this time, unnecessary parts are removed by etching so that the edge part of the aluminum electrode is not vertical but stepped, but in normal wet etching, the shape of the edge part of the aluminum electrode is referred to in the above-mentioned conventional technique. Since it is almost vertical as shown in FIG. 21, it was decided to etch the resist at the same time as Al.

【0053】

Here, a method for removing Al will be described with reference to FIG.

【0054】

A positive resist (photoresist) 121 is applied to the Al deposited on the entire surface to a thickness of 1.2 μm, and patterning is performed for electrode formation ((a) in FIG. 16). Next, wet etching of the Al part is performed. The etching solution of Al used at this time is phosphoric acid (H).₃ PO₄ ), Nitric acid (HNO)₃ ) And acetic acid (CH)₃ A mixture of COOH) is well known. The etching solution temperature was 30 ° C to 50 ° C. Further, the etching of the Al part is performed about half of the total Al film thickness. At this time, the etching rate of the Al part was about 3000 Å / min, and the etching time was calculated from the value obtained by dividing about half of the Al film thickness by the above etching rate ((b) in FIG. 16).

【0055】

Next, in order to retreat the positive resist 121, it is immersed in an aqueous solution of TMAH (trimethylammonium hydroxide). At this time, the concentration of the TMAH aqueous solution is 2 to 3%, and the liquid temperature is 30 ° C to 40 ° C. The amount of retreat at this time could be controlled in the range of 0.5 to 1.0 μm / min by changing the liquid temperature ((c) in Fig. 16).

【0056】

Next, the remaining Al part is etched. The etching solution at this time is the same as described above. The end point of etching is determined by the change in reflectance on the wafer surface ((d) in FIG. 16).

【0057】

Next, the positive resist 121 is removed using an organic amine-based stripper ((e) in FIG. 16).

【0058】

As described above, by repeating etching resist retreat etching, as shown in FIG. 16 (e), the end face and the side wall, that is, the entire side surface of the Al electrode could be formed in a stepped shape.

【0059】

(6) Next, SiO which becomes an interlayer film 102 having a function as a heat storage layer 101 by a sputtering method.₂ A film was formed on the entire surface by about 0.6 to 1.0 μm. SiO₂The film may be by the CVD method. Also, SiO₂ The film is not limited to the film, and may be a SiO film or a SiON film.

【0060】

Next, in order to make an electrical connection, a part of the interlayer film 102 above the emitter region 10 and the base collector regions 8 and 11 was opened by photolithography to form a through hole (TH) (above). Figure 12).

【0061】

(7) Next, HfB as the heat generation resistance layer 103₂ Was deposited on the interlayer film 102 and on the emitter electrode 13 and the collector-base common electrode 12 which are the upper parts of the emitter region 10 and the base collector regions 8 and 11 for electrical connection through TH.

【0062】

(8) A material layer made of Al material for forming a pair of wirings 104 and 104 of the heat generating portion 110, a cathode electrode wiring 104 of the diode, and an anode electrode wiring 109 is deposited on it for about 5000 Å, and Al and HfB are deposited.₂ Was patterned, and the heat generating portion 110 and the wiring 104 for making other connections were formed at the same time. The patterning of Al is the same as the method (5) above (Fig. 13 above).

【0063】

(9) SiO as an insulating layer between the protective layer of the heat generating portion 110 and the wiring 104 of Al by the sputtering method or the CVD method.₂ After depositing the protective film 105 of the film for about 6000 Å, Ta was deposited on the upper part of the heat generating portion 110 for about 2000 Å as the protective film 106 for cavitation resistance. Further, the heat generating portion 110, Ta and the protective film 105 thus created were partially removed to form a bonding pad 107. The protective film 105 is SiO₂ Surprisingly, it may be SiON or SiN (Fig. 14 above).

【0064】

(10) A liquid passage wall member 501 and a top plate 502 for forming a discharge port 500 are arranged on a substrate 100 having a semiconductor functional element formed as described above, and a liquid passage 505 is provided inside them. And a recording head 600 forming a common liquid chamber 504 was manufactured (above FIG. 15).

【0065】

With respect to the recording head 600 manufactured in this way, the heat generating portion 110 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 300mA (2.4A in total) was passed through each semiconductor diode, but the other semiconductor diodes did not malfunction and good discharge was possible. did it. In addition, since the container recording head has good heat transfer efficiency, the drive power is 80% of that of the conventional one, and the high frequency response is excellent. Furthermore, excellent characteristics were obtained in terms of life and uniformity.

【0066】

Further, as shown in the above-mentioned steps (5) and (8), when the etching of Al is performed in two steps, the etching film thickness of the first (1st etching) and the second (2nd etching) is controlled. , It has become possible to optimally match the step coverage of the interlayer film 102. The results are shown in Table 1.

【0067】

[table 1]

* Step coverage: -good, ×-bad As is clear from Table 1 above, the step coverage of the interlayer film 102 is better when the film thickness difference between the 1st etching and the 2nd etching is not large.

【0068】

Further, when the Al etching shown in the above steps (5) and (8) is performed, Al etching is performed twice or more in the order of Al etching resist retreat Al etching resist retreat Al etching. As shown in, the number of steps of the Al end face and the side wall formed can be increased. FIG. 17 shows the cross-sectional shape of the end face of the Al wiring 104 when the Al etching is performed in four steps.

【0069】

This makes it possible to further improve the step coverage of the interlayer film 102.

【0070】

By attaching the recording head 600 having the above-described configuration to the inkjet recording device main body and applying a signal from the device main body to the recording head 600, it is possible to obtain an inkjet recording device capable of performing high-speed recording and high-quality recording. ..

【0071】

Here, the inkjet recording apparatus using the recording head of the present invention will be described with reference to FIG.

【0072】

FIG. 18 is an overview perspective view showing an example of the inkjet recording apparatus 700 to which the present invention is applied.

【0073】

The recording head 600 is mounted on a gear ridge 720 that engages with a spiral groove 721 of a lead screw 704 that rotates via drive force transmission gears 702 and 703 in conjunction with forward and reverse rotation of the drive motor 701. It is reciprocated along the guide 719 along with the gear ridge 720 in the directions a and b by the power of the motor 701. Reference numeral 705 is a paper presser plate for recording paper P conveyed on the platen 706 by a medium feeding device (not shown), and presses the recording paper P against the platen 706 in the direction of movement of the gear ridge. Reference numerals 707 and 708 are photocouplers, and are home position detecting means for confirming the existence of the lever 709 of the gear ridge 720 in this region and switching the rotation direction of the drive motor 701. 710 is a support member that supports the cap member 711 that caps the front surface of the recording head 600, and 712 is a suction means that sucks the inside of the cap member 711 to recover the suction of the recording head 600 through the opening inside the cap 713. Do. Reference numeral 714 is a cleaning blade, and reference numeral 715 is a moving member that enables the blade to move in the front-rear direction, and these are supported by the main body support plate 716. It goes without saying that the cleaning blade 714 can be applied to other well-known cleaning blades other than this form. Further, the 717 is a lever for starting suction for suction recovery, which moves with the movement of the cam 718 that engages with the carriage 720, and the driving force from the drive motor 701 is transmitted by a known transmission means such as clutch switching. Movement is controlled. A print control unit that applies a signal to the heat generating unit 110 provided in the recording head 600 and controls the drive control of each mechanism described above is provided on the device main body side (not shown).

【0074】

The inkjet recording device 700 having the above-described configuration records the recording paper P conveyed on the platen 706 by the medium feeding device while the recording head 600 reciprocates over the entire width of the recording paper P. Since the recording head 600 is manufactured by the method described above, high-precision and high-speed recording is possible.

【0075】

In the case of the substrate 100 in the recording head 600 described above, the connection end surface and side surface of the wiring 104 made of Al and the entire side surface of each electrode of the functional element are formed in a stepped shape, but such a configuration is not always necessary. .. It is also effective that the surface perpendicular to the direction in which the current flows (in the case of the wiring 104, the connection end surface in the heat generating portion 110) is formed in a stepped shape.

【0076】

A method of forming such a stepped end face will be described with reference to FIGS. 19A to 19E, taking the case of wiring 104 as an example.

【0077】

In the above-mentioned substrate 100, HfB as the heat generation resistance layer 103₂ After depositing a layer made of Al material as wiring 104, the heat generation resistance layer 103 and wiring 104 are formed by repeating the conventional photolithography process twice (a).

【0078】

At this time, as the etching method of the wiring 104, there are a wet etching method conventionally used or a dry etching method using RIE or the like using a Cl-based gas. By these methods, the side surface of the wiring 104 in the longitudinal direction has an angle substantially perpendicular to the surface of the heat generation resistance layer 103.

【0079】

Next, the area other than the area corresponding to the heat generating portion 110 is covered with resists 111, 111'by a conventional method (b), and immersed in the TMAH aqueous solution in the same manner as the Al removal described in the manufacturing process (5) of the recording head 600 described above. While repeating etching and resist retreat, the region corresponding to the heat generating portion 110 of the wiring 104 is peeled off to form the heat generating portion 110 (c). At this time, the two connecting end faces of the wiring 104 in the heat generating portion 110 are formed in a stepped shape as described above (d), and the side surface is a surface substantially perpendicular to the surface of the lower heat generating resistance layer 103. (e).

【0080】

This method can be similarly considered for each electrode of the functional element, and only the connection end face of each electrode can be formed in a stepped shape.

【0081】

The present invention brings about an excellent effect especially in a recording head and a recording device of a method of ejecting ink by utilizing heat energy proposed by Canon Inc. among the inkjet recording methods.

【0082】

As for the typical structure and principle, for example, it is preferable to use the basic principle disclosed in US Pat. Nos. 4,723,129 and 4740796. This method can be applied to both the so-called on-demand type and the continuous type, but in the case of the on-demand type in particular, it is arranged corresponding to the sheet or liquid passage in which the liquid (ink) is held. By applying at least one drive signal that corresponds to the recording information and gives a rapid temperature rise exceeding nucleate boiling to the electric heat conversion element, heat energy is generated in the electric heat conversion element, and the recording head It is effective because the film can be boiled on the heat acting surface, and as a result, bubbles in the liquid (ink) can be formed in a pair-to-pair correspondence with this drive signal. The growth and contraction of the bubbles causes the liquid (ink) to be ejected through the ejection opening to form at least one drop. When this drive signal has a pulse shape, the growth and contraction of bubbles are immediately and appropriately performed, so that liquid (ink) with particularly excellent responsiveness can be ejected, which is more preferable. As the drive signal having this pulse shape, those described in US Pat. Nos. 4,463,359 and 4345262 are suitable. Further excellent recording can be performed by adopting the conditions described in US Pat. No. 4,313,124 of the invention relating to the temperature rise rate of the heat acting surface.

【0083】

As the configuration of the recording head, in addition to the combination configuration (linear liquid flow path or right-angled liquid flow path) of the discharge port, the liquid passage, and the electric heat conversion element as disclosed in each of the above specifications, the heat acting unit It may be the configuration described in US Pat. No. 4,558,333, US Pat. No. 4,459,600, which discloses the configuration in which the is arranged in the bending region. In addition, Japanese Patent Application Laid-Open No. 123670, which discloses a configuration in which a common slit is used as a discharge portion of the electric heat conversion element for a plurality of electric heat conversion elements, and an opening for absorbing a pressure wave of thermal energy. The present invention is also effective as a configuration based on Japanese Patent Application Laid-Open No. 138461, which discloses a configuration corresponding to a discharge portion.

【0084】

Further, as a full-line type recording head having a length corresponding to the width of the maximum recording paper that can be recorded by the recording device, the length can be determined by a combination of a plurality of recording heads as disclosed in the above specification. The configuration may be either a satisfying configuration or a configuration as a single recording head integrally formed, but the present invention can more effectively exert the above-mentioned effects.

【0085】

In addition, it is provided integrally with a replaceable chip-type recording head that can be electrically connected to the device body and supply ink from the device body by being attached to the device body, or the recording head itself. The present invention is also effective when the cartridge type recording head is used.

【0086】

Further, it is preferable to add a recovery means, a preliminary auxiliary means, or the like provided as a configuration of the recording device of the present invention to the recording head because the effect of the present invention can be further stabilized. Specifically, these are a cleaning means, a pressurizing or suction means, an electric heat exchange element or another heating element for the recording head, or a preheating means by a combination thereof, which is different from the recording. Performing a preliminary discharge mode for discharging is also effective for stable recording.

【0087】

Further, the recording mode of the recording device is not limited to the recording mode of only mainstream colors such as black, and the recording head may be integrally configured or a combination of a plurality of colors may be used. The present invention is also extremely effective for devices equipped with at least one full color.

【0088】

In the embodiment of the present invention described above, the ink is described as a liquid, but an ink that solidifies at room temperature or lower and softens or becomes liquid at room temperature, or is generally used in inkjet. It may be softened or liquid in the temperature range of 30 ° C or more and 70 ° C or less, which is the temperature range of the temperature adjustment. That is, the ink may be liquid when the usage recording signal is applied. In addition, an ink that is positively prevented from rising due to thermal energy by using it as energy for changing the state of the ink from a solid state to a liquid state, or an ink that solidifies in an unattended state for the purpose of preventing ink evaporation. In any case, thermal energy such as those in which the ink is liquefied by applying the thermal energy according to the recording signal and discharged as an ink liquid, or those that have already started to solidify when the ink reaches the recording paper. The use of ink that liquefies for the first time is also applicable to the present invention. In such a case, the ink is held as a liquid or solid in the recesses or through holes of the porous sheet as described in JP-A-54-56847 or JP-A-60-71260. It may be in a form facing the electric heat exchange element. In the present invention, the most effective one for each of the above-mentioned inks is to carry out the above-mentioned film boiling method.

【0089】

[Effect of the invention]

As described above, according to the present invention, the following effects are obtained.

【0090】

According to the substrate for an inkjet recording head of the present invention, the connection end surface of the wiring electrode can be easily and highly accurately formed into a desired shape such as including a step, and the unevenness of the lower film is caused by the wiring electrode. Since it can be formed gently and has excellent step coverage, it has become possible to thin the upper and lower protective films and interlayer films.

【0091】

Further, since the wiring electrode and the electric heat conversion element are in contact with each other at the stepped connection end face in the heat generating portion, the current concentration at the end of the electric heat conversion element can be significantly alleviated. Further, by thinning the film, the heat conduction efficiency is improved, and a recording head having low power consumption and good frequency response can be realized at low cost. Further, since the current concentration can be relaxed, the life of the recording head is extended and uniform characteristics can be obtained.

【0092】

That is, a highly reliable and highly uniform recording head could be obtained at low cost.

【0093】

Further, in the inkjet recording device, high-speed recording operation can be achieved, switching characteristics are fast, rising characteristics are improved, and there is little parasitic effect, so that suitable thermal energy can be applied to the ink, and the accuracy of recording operation is improved. ..

[Simple explanation of drawings]

[Figure 1]

It is a schematic cross-sectional view which shows an example of the substrate for an inkjet recording head of this invention.

[Figure 2]

It is a figure which shows an example of the electrode of the substrate for an inkjet recording head of this invention, (a) is a sectional view, (b) is a plan view.

[Fig. 3]

It is a figure which shows an example of the heat generating part of the substrate for an inkjet recording head of this invention, (a) is a sectional view, (b) is a plan view.

[Fig. 4]

It is sectional drawing which shows an example of the electric current which flows through the heat generating part of the substrate for an inkjet recording head of this invention.

[Fig. 5]

It is sectional drawing for demonstrating operation of the substrate for an inkjet recording head of this invention.

[Fig. 6]

It is a perspective view which shows an example of the inkjet recording head of this invention.

[Fig. 7]

It is sectional drawing which shows an example of the manufacturing process of the substrate for an inkjet recording head and the inkjet recording head of this invention.

[Fig. 8]

It is sectional drawing which shows an example of the manufacturing process of the substrate for an inkjet recording head and the inkjet recording head of this invention.

[Fig. 9]

It is sectional drawing which shows an example of the manufacturing process of the substrate for an inkjet recording head and the inkjet recording head of this invention.

[Fig. 10]

It is sectional drawing which shows an example of the manufacturing process of the substrate for an inkjet recording head and the inkjet recording head of this invention.

[Fig. 11]

It is sectional drawing which shows an example of the manufacturing process of the substrate for an inkjet recording head and the inkjet recording head of this invention.

[Fig. 12]

It is sectional drawing which shows an example of the manufacturing process of the substrate for an inkjet recording head and the inkjet recording head of this invention.

[Fig. 13]

It is sectional drawing which shows an example of the manufacturing process of the substrate for an inkjet recording head and the inkjet recording head of this invention.

[Fig. 14]

It is sectional drawing which shows an example of the manufacturing process of the substrate for an inkjet recording head and the inkjet recording head of this invention.

[Fig. 15]

It is sectional drawing which shows an example of the manufacturing process of the substrate for an inkjet recording head and the inkjet recording head of this invention.

[Fig. 16]

It is sectional drawing which shows an example of the manufacturing process of the electrode of the substrate for an inkjet recording head of this invention.

[Fig. 17]

It is sectional drawing which shows another example of the heat generating part of the substrate for an inkjet recording head of this invention.

[Fig. 18]

It is a perspective view which shows one Example of the inkjet recording apparatus of this invention.

[Fig. 19]

It is sectional drawing which shows another example of the manufacturing process of the heat generating part of the substrate for an inkjet recording head of this invention.

[Fig. 20]

It is sectional drawing which shows an example of the substrate for the conventional inkjet recording head.

[Fig. 21]

It is sectional drawing which shows the electric current which flows in the heat generating part of the substrate for the conventional inkjet recording head.

[Explanation of symbols]

1 P-type silicon substrate 2 N-type collector embedded area 3 P-type isolation embedded area 4 N-type epitaxial region 5 P-type base area 6 P-type isolation region 7 N-type collector area 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 Collector-base common electrode 13 Emitter electrode 14 Isolation electrode 100 Hypokeimenon 101 Thermal storage layer 102 interlayer film 103 Heat resistance layer 104 Wiring 105,106 Protective film 107 Bonding pad 109 Anode electrode wiring 110 Heat generating part 401 drive current 500 discharge port 501 Liquid passage wall member 502 Top plate 503 Ink supply port 504 Common liquid chamber 505 fluid channel 600 Inkjet recording head 700 Inkjet recording device 701 drive motor 702,703 Driving force transmission gear 704 Reed screw 705 Paper presser plate 706 Platen 707,708 Optocoupler 709,717 lever 710 Support member 711 Cap member 712 Suction means 713 Opening inside the cap 714 cleaning blade 715 Moving member 716 Body support plate 718 cam 719 guide 720 carriage 721 spiral groove