JP2008120003A - Inkjet recording head and manufacturing method for substrate for the head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that a wide beam formed in the supply port becomes an obstacle between an ejection pressure generating element part heating an ink and a supply port, affecting a filling speed of the ink to an ejection opening and hindering the ejection pressure generating element part near the beam from obtaining an ejection performance uniform to that of the other parts, and that a sufficient strength cannot be obtained when a beam width is narrowed. <P>SOLUTION: In the inkjet recording head, ink ejection pressure generating elements are prepared on a silicon single crystal substrate, and the ejection openings are arranged at a plate side opposed to the ink ejection pressure generating elements. The ink is ejected perpendicularly to the ejection opening substrate by generating bubbles in the ink. The head has a plurality of the ink supply ports arranged continuously in a longitudinal direction to the substrate. A top part of the beam between the continuous ink supply ports is formed by a surface surrounded by a lattice plane with a principal plane of an orientation (111). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an inkjet recording head that discharges a desired liquid by applying energy to the liquid from the outside, and a method for manufacturing the head substrate.

  There is known an ink jet recording method in which the generation of bubbles is promoted by applying energy such as heat to the ink, the ink is ejected from the ejection port using this volume change, and this is deposited on the recording medium to form an image. It has been. Among ink jet systems, a side shooter type (Japanese Patent Laid-Open No. 4-10940) that ejects ink perpendicular to a substrate has been proposed. In this side shooter type, a hole 902 that penetrates the substrate 901 is formed as shown in FIG.

In the conventional side shooter type ink jet recording head, since the head width is short, the through hole is a single hole connected to the opening. However, if an attempt is made to produce a long head that can print on a large area at a time by widening the head width, the ink supply port becomes longer, the mechanical strength becomes weaker, and the possibility of deformation or destruction of the head increases. . Therefore, it is necessary to divide the supply port for providing the tension in the longitudinal direction of the supply port. Japanese Laid-Open Patent Publication No. 10-138478 discloses a substrate for an ink jet recording head that is divided into a plurality of parts by a splint.
Japanese Patent Laid-Open No. 4-10940 JP-A-10-138478

  On the other hand, if a wide tension is created in the supply port, it becomes an obstacle between the discharge pressure generating element that heats the ink and the supply port, affecting the filling speed of the ink in the discharge port, There is a problem in that the discharge pressure generating element portion in the vicinity cannot obtain discharge performance uniform with other portions. On the other hand, there was also a problem that sufficient strength could not be obtained if the tension width was narrowed.

  The above-mentioned problems are that an ink discharge pressure generating element is provided on a silicon single crystal substrate, and a discharge port is disposed on the plate side facing the ink discharge pressure generating element, and ink is discharged vertically to the discharge port substrate. In the inkjet recording head, a plurality of ink supply ports are continuously arranged in the longitudinal direction on the substrate, and the upper surface of the gap between the continuous ink supply ports is a crystal plane with the (111) orientation as the main surface It was solved by an ink jet recording head characterized by being formed by a surface surrounded by.

  The present invention relates to a method for manufacturing a substrate for an ink jet recording head in which a through hole is formed as an ink supply port in a silicon substrate, and the silicon substrate can be selectively etched in a formation portion of an ink supply port on the surface of the silicon substrate. Providing an adjacent sacrificial layer close to the surface of the silicon substrate facing the ink supply port on the back so that the (111) surface appearing during anisotropic etching is in contact with the silicon substrate surface; A step of forming a passivation layer having etching resistance so as to cover the sacrificial layer, a step of providing an etching mask opening separated so as to leave a part of the back surface of the substrate corresponding to the sacrificial layer, and Etching the substrate by crystal axis anisotropic etching until the sacrificial layer is exposed from the opening, and exposing the substrate by the etching process. Etching the sacrificial layer from the etched portion, etching the upper portion of the relief until it becomes lower than the substrate surface, and stopping the upper portion of the relief at the (111) plane; and removing the passivation layer to form an ink supply port; It implement | achieves by the manufacturing method of the board | substrate for inkjet recording heads characterized by having.

  Even when the width of the ink jet recording head is widened, it is possible to provide an ink jet recording head that has sufficient mechanical strength and can perform high-quality printing without increasing the resistance of the ink flow path.

  Hereinafter, the experiment relating to the present invention will be described first, and then the present invention will be described in detail by showing embodiments and further showing examples and comparative examples.

[Experiment 1]
Below, the experiment concerning this invention is described. The frequency characteristics of ink ejection at the ridges and openings between successive supply ports were examined.

  FIG. 2 shows an outline of the plane in the vicinity of the discharge port of the substrate of the ink jet recording head used in the experiment of the present invention. The pitch of the discharge ports was 43 μm. In this ink jet recording head, a tension 406 having a cross section as shown in FIG. 6 is provided inside the ink supply port in order to increase the strength of the substrate. In this case, the upper part of the tension is formed at the same height as the substrate surface.

  The distance CH from the ink supply port end 203 to the discharge pressure generating element (heater) 201 located at the lower portion of the discharge port was 50 μm. The distance from the discharge port to the nozzle filter 205 was 40 μm, and the interval was 25 μm. At this time, when the width of the substrate surface portion of the portion of the tension 204 was set to 25 μm, the limit frequency at which ink ejection could respond when a 5.5 pl ink droplet was ejected was examined.

  FIG. 7 shows the relationship between the limit response frequencies of the discharge ports at the respective positions. The critical discharge frequency was 10.5 KHz at the discharge port (bit No. 35) where the elasticity is directly in front of the heater. In addition, the limit response frequency of the discharge port that was 100 μm or more away from the sprout in the direction parallel to the supply port was 15 to 17 kHz.

[Experiment 2]
FIG. 1 is a plan view of an ink jet recording head according to the present invention, in which a cut portion of a substrate surface between ink supply ports is removed by etching. FIG. 4 shows the cross section of the cross section, and the top 308 of the scale was measured at 100 points and found to be an average 50 μm below the substrate surface. The other dimensions of the head were designed to be the same as those in Experiment 1.

  FIG. 8 shows the relationship between the limit response frequencies of the ejection ports at each position when printing is performed using this ink jet recording head. Even the discharge port (bit No. 35) directly beside the sprung had a performance equal to that of the discharge port disposed away from the spruce at a limit discharge frequency of 16 KHz.

[Experiment 3]
FIG. 3 shows a cross-sectional structure before etching in the vicinity of the elasticity of the ink supply port. 9 is a top view thereof, and FIG. 10 is a bottom view thereof. The substrate 301 is a Si single crystal whose surface is (110). The ink supply port pattern 304 on the front surface is formed of AlCu on a parallelogram parallel to the (111) orientation on Si, and becomes a sacrificial layer when anisotropic etching is performed from the back surface. The ink supply port pattern 302 on the back surface was formed as a parallelogram parallel to the (111) orientation by etching the oxide film on Si to expose Si.

  At this time, the interval 303 between the supply ports on the back surface was fixed to 120 μm, and the width 305 between the sacrificial layers on the top surface was changed to observe the shape of the cross section after anisotropic etching. The thickness of the Si wafer was 635 μm.

  When etching was performed in a TMAH aqueous solution at 83 ° C. and a concentration of 22% for 7 to 8 hours, when the sacrificial layer interval was 2 μm or more and less than 20 μm, a relief structure having a shape as shown in FIG. 4 could be formed. This is because the uppermost part of the tension falls from the substrate surface and does not prevent ink refilling when the ink jet recording head is manufactured.

  On the other hand, when the distance between the sacrificial layers is 20 μm or more, the cross section has a shape as shown in FIG. 6, and a part of the hull remains at the same height as the substrate surface. This becomes resistance to ink flow. At this time, if the etching time is further extended and etching is continued until the (111) surface collides with the top of the tension, the effect of forming the ink supply port by the sacrificial layer is lost, and the phenomenon that the supply port side surface undulates appears. The distance between the mouth and the heater cannot be kept constant.

  Further, when the sacrificial layer interval was 2 μm or less, the top section of the relief became a shape as indicated by 703 in FIG. It is thought that this is because the upper part of the elasticity was etched randomly, and the shape and height of the elasticity did not become uniform. Furthermore, in this structure, since the upper part of the rib is not covered with a plane having an orientation close to the (111) plane, the shape is changed rapidly by alkaline ink, and there is a high possibility that the strength cannot be maintained. Also, the silicon dissolved in the ink adheres to the heater part and causes non-ejection nozzles.

  Here, as shown in FIG. 4, when 20 cross sections of the upper part surrounded by a crystal plane with the (111) orientation as the main surface were inspected, an error of 15 degrees at the maximum was found in the plane orientation. . This is due to fluctuations in the etched surface during anisotropic etching. However, as a result of the ink immersion test at 60 ° C. for 4 weeks, even when the plane orientation has a deviation of about 15 degrees, the erosion of the elasticity is at a level that causes no problem in practice.

[Example Embodiment]
FIG. 1 is a schematic view of a base substrate of an ink jet recording head showing an embodiment according to the present invention. (FIG. 4 is an AB cross-sectional view, and FIG. 11 is an overhead view (nozzle not shown)). A (110) -oriented Si wafer is used as the substrate. A through hole 103 for supplying ink from the back surface is formed in the center of the substrate. When the width of the ink jet recording head nozzle is increased, the supply port cuts through the center of the substrate, so that the strength of the substrate is reduced, and the possibility of deformation or breakage increases. Therefore, the supply port is divided into a plurality of parts as shown in FIG. At this time, the upper part of the tension (ink discharge pressure generating element forming surface side) becomes the resistance of the ink flow path, and the ink supply is disturbed when the ink jet is driven at a high frequency. In order to avoid this, as shown in FIG. 4, the upper part of the gap between the ink supply ports is etched with the surface surrounded by the (111) plane, and the vertex of the tension is formed on the substrate on which the ink discharge pressure generating element is formed. It is formed at a position lower than the surface. At this time, only the surface portion of the substrate is removed by etching, so that a decrease in strength is not a problem.

  When a Si wafer is used as a substrate, the width of the supply port is generally 50 to 300 μm, desirably 80 to 200 μm, and optimally 100 to 200 μm. The length of the divided supply port is generally 0.5 to 40 mm, preferably 1 to 10 mm, and most preferably 1.5 to 5 mm. The width of the back side tension is generally 30 to 300 μm, preferably 60 to 200 μm, and most preferably 80 to 150 μm.

  FIG. 12 shows the structure of the CD cross section of the substrate of FIG. The ink supplied from the direction of the lower ink supply port 506 is heated by the heater 503 and foamed and discharged from the nozzle 505. At this time, even in the heater portion that is located directly beside the tension in the plane, an ink flow path that does not impede the supply speed is secured on the tension 502, so that the ink ejection performance equivalent to that of other heater sections is achieved. can get.

  Next, the process of the ink jet recording nozzle according to the present invention will be described step by step with reference to FIGS. Note that the steps in FIGS. 13 to 19 are a series of steps, and are therefore given serial numbers for convenience. However, FIG. 19 (19) shows a plan view of the sacrificial layer pattern in the step of FIG. 13 (2), and FIG. 19 (20) shows the silicon substrate 601 in the step of FIG. FIG.

  13 (1) An insulating film 602 is formed on a silicon substrate 601 having a substrate surface orientation (110) of, eg, thermal oxidation or CVD, and an ink supply port is provided as shown in FIG. 13 (1) by photolithography. A desired pattern 603 is formed.

  13 (2) A metal having a low resistance such as Al or Cu and a high etching rate for an etchant for anisotropic etching such as TMAH (tetramethylammonium hydride) is deposited and patterned to sacrifice the lower layer wiring 604. Layer 605 is formed. The etching sacrificial layer is an etching rate that is much faster than the Si wafer when etching proceeds from the back surface and the etchant reaches the sacrificial layer, so that etching can be performed in a short time and an opening corresponding to the sacrificial layer pattern can be opened. is there. The pattern at this time is a parallelogram with a narrow angle of 70.5 degrees as shown in FIG. 19 (19) so that an etching hole is perpendicular to the substrate, and the long side and the short side of the parallelogram are It arrange | positions so that it may become parallel to a surface equivalent to (111).

  At this time, the distance between the sacrificial layers is generally 2 to 20 μm, preferably 3 to 15 μm, and optimally 4 to 13 μm. Further, the thickness of the sacrificial layer is generally 3000 mm or less, preferably 2500 mm, and optimally 2000 mm or less.

  In FIG. 13 (3), an SiN or SiON film is deposited as an etching stop layer 606 on the substrate surface by plasma CVD. As the etching stop layer, two or more kinds of films may be laminated in order to adjust the film stress.

The total thickness of the laminated etching stop film is generally 2000-2 μm, preferably 3000-15000 mm, and most preferably 4000-13000 mm. The total stress of the laminated etching stop film is generally 2 × 10 exp-9 dyne / cm ² or less, more preferably 1.8 × 10 exp-9 dyne / cm ² or less, and most preferably 1.5 × 10 exp-9 dyne / cm ^2. / cm ² or less.

13 (4) A film such as SiN, SiON, or SiO ₂ is deposited by plasma CVD or the like to form an interlayer insulating film 607. Further, a contact hole 608 is formed in the interlayer insulating film.

  In FIG. 13 (5), a heater portion 609 is formed as an ink discharge pressure generating element in accordance with the ink supply port. As the heater material, a metal film such as Ta, TaN, TaNSi or the like is deposited and patterned by sputtering, vacuum evaporation or the like. Further, a metal film of Al, Mo, Ni, Cu or the like is formed in the same manner as the upper layer electrode 610 for supplying power.

  In FIG. 14 (6), a SiN film 611 is deposited on the heater by plasma CVD for the purpose of improving the durability, and used as a protective film.

  14 (7) On this, Ta is deposited and patterned as a cavitation resistant film 612 by sputtering or the like. The thickness of this film is preferably 1000 to 5000 mm, more preferably 2000 to 4000 mm, and most preferably 2500 to 3500 mm.

  Needless to say, there is no particular limitation on the order of forming the wiring and the heater.

  FIG. 14 (8) A resin film 613 with high corrosion resistance is formed in order to improve the adhesion of the resin nozzle and to protect the back surface from the alkaline etchant. Then, the heater part and the ink supply port part are patterned.

  FIG. 15 (9) In order to secure the ink flow path, the pattern 614 is formed of a resin that can be dissolved with a strong alkali or an organic solvent. This pattern is formed by a printing method or patterning with a photosensitive resin.

  FIG. 15 (10) A coating resin layer 615 is formed on the ink flow path pattern. Since this coating resin layer forms a fine pattern, a photosensitive resist is desirable, and further, the coating resin layer must have a property of not being deformed and altered by an alkali, a solvent, or the like when the resin layer having the flow path is removed.

  FIG. 15 (11) Next, the coating resin layer of the flow path is patterned to form the ink discharge port 616 corresponding to the heater portion 609 and the external connection portion of the electrode. Thereafter, the coating resin layer is cured by light or heat.

  FIG. 16 (12) A protective film 617 is formed with a resist to protect the nozzle forming surface side of the substrate.

In FIG. 16 (13), the pattern portion 618 of the ink supply port on the back surface is removed from the back surface such as SiN or SiO ₂ by using a photolithography technique to expose the wafer surface. The shape of this pattern is formed to have a mirror image relationship with the sacrificial layer as shown in FIG. The manufacturing method of the etching mask film on the back surface is not limited to plasma CVD, but may be LPCVD, atmospheric pressure CVD, thermal oxidation, or the like.

  Next, an etching leading hole 619 is formed in a portion near the narrow angle of the parallelogram on the back surface (plan view 19 (20) on the back surface). Generally, laser machining or the like is used, but electric discharge machining, blasting, or the like may be used.

  This lead hole can be as close as possible to the etching stop layer. The depth of the leading hole is generally 60% or more of the substrate thickness, preferably 70% or more, and optimally 80% or more. Also, it must not penetrate the substrate. This leading hole suppresses the oblique (111) plane generated from the narrow angle of the parallelogram during anisotropic etching.

  FIG. 17 (15) When this substrate is immersed in an alkali-based etchant (KOH, TMAH, hydrazine, etc.) and anisotropic etching is performed so that the (111) plane appears, a through hole having a parallelogram shape in the plane is formed.

  In FIG. 17 (16), the SiN film of the etching stop layer 606 is partially removed by a chemical solution such as hydrofluoric acid or dry etching to open the ink supply port. Finally, the ink flow path forming material 614 is removed to secure the ink flow path 620.

  FIG. 17 (17) In the above process, the substrate processing procedure is not particularly limited, and can be arbitrarily selected.

  Examples of the present invention will be described below.

  FIG. 1 is a schematic diagram showing the structure of a base substrate of an ink jet recording head according to the present invention. FIG. 4 shows the peripheral portion of the ink supply port 103 of the substrate formed by etching a Si wafer (substrate) having a surface orientation of (110) and having a thickness of 630 μm perpendicularly to the substrate. In the peripheral portion of the substrate supply port shown in FIG. 4, the vertices 308 are formed 60 μm below the substrate surface. This ink supply port has a planar structure in which the long side is parallel to the (111) plane, the width is 100 μm, the length is 2 mm, and the angle between the short side and the long side is 70.5 degrees. Thirty pieces were arranged in a row with the back 104 having a width of 140 μm. FIG. 11 is an overhead view (nozzle portion not shown) of the ink supply port as viewed from the substrate surface. The through-hole was opened perpendicular to the substrate with the long side parallel to the (111) plane, the width of 100 μm, the length of 2 mm, and the angle between the short side and the long side being 70.5 degrees. On both sides of the ink supply port, a TaN heater 106 having a thickness of 200 mm and 24 μm □ was disposed at intervals of 60 μm. Each heater is connected to an Al wiring 108 having a thickness of 3000 mm so that an electric signal can be supplied individually.

  FIG. 12 is a schematic view of the CD cross section of FIG. An opening 505 is provided in the nozzle forming resin immediately above each heater 503, and ink is ejected from this portion.

  When ink droplets of 5.5 pl are ejected using this ink jet recording head, the maximum ejection frequency is 15 KHz, and high-quality printed matter free from printing blur, density unevenness, and non-ejection of ink over the entire width of 60 mm. Obtained.

[Comparative Example 1]
Below, the comparative example of this invention is demonstrated.

  The structure of the heater, electrodes, nozzles, and the like on the substrate surface is the same as that of Example 1, and the structure is such that the surface of the substrate remains sharp as shown in FIG. The surface width was 30 μm.

  The structure of the heater, electrode, nozzle forming resin, etc. on the upper surface of the substrate was the same as in Example 1.

  Using this ink jet recording head, a printing test was performed with 5.5 pl of ink droplets at a discharge frequency of 15 KHz. Discharge from the nozzle portion directly beside the sprout with a period of 2 mm was disturbed, and there was a portion where printing density unevenness was seen. there were.

  Other embodiments of the present invention will be described below.

  FIG. 21 is a cross-sectional view of a cut portion. In the first embodiment, only the shape of the cut cross section is changed by widening the interval between the sacrificial layers in the intermediate process.

  The relief surface was etched and surrounded by a surface close to the (111) plane, and the vertex of the relief was formed 20 μm below the substrate surface. The other parts were the same as in Example 1.

  Using this ink jet recording head, a printing test was performed with 5.5 pl of ink droplets at an ejection frequency of 12 KHz, but a high-quality printed matter without blurring, density unevenness, and non-ejection of ink was observed over the entire 60 mm width. Obtained.

  Below, the manufacturing method of the ink jet recording head according to the present invention will be explained step by step.

As shown in FIG. 13 (1), the (110) plane Si wafer 601 having a thickness of 630 μm and 6 inches of Φ is thermally oxidized to form a SiO ₂ layer 602 having a thickness of 6000 mm, and SiO ₂ is patterned and supplied. A mouth opening 303 was formed. 2000 liters of AlCu film was deposited with a sputter. The Cu content of this film was 0.5%. A sacrificial layer 605 lower electrode wiring 604 was formed by photolithography as shown in FIG. The width of the sacrificial layer was 180 μm, the long side direction was 2 mm, and the width of the portion between adjacent sacrificial layers was 6 μm. As in the embodiment, the sacrificial layers are parallelograms having an angle between the short side and the long side of 70.5 degrees, and 40 sacrificial layers are arranged in series with a pinch interposed therebetween.

  Next, 12000 mm of SiN film 606 was deposited by plasma CVD as an etching stop layer.

The film formation conditions at this time were SiH ₄ / NH ₃ / N ₂ = 500/1500/6300 sccm, pressure 1500 mtorr, substrate temperature 400 ° C., and RF 1700 W.

The photolithographic technique was used to pattern the etching stop layer as shown in FIG. 13 (3), and then 14000 nm of SiON was formed as the interlayer insulating film 607. The film formation parameters at this time were SiH ₄ / N ₂ O / N ₂ = 250/1200/4000 sccm, pressure 1500 mtorr, substrate temperature 380 ° C., RF 1700 W, composition ratio Si / O / N = 37/61/2. .

  Thereafter, as shown in FIG. 13 (4), a contact hole 608 is formed in the interlayer insulating film, and 500 nm of TaSiN (composition ratio 44/43/13) and 3000 of Al are continuously formed and patterned. The heater 609 and the upper wiring 610 were formed as in (5).

Next, 3000 nm of plasma CVD SiN was deposited and patterned as the heater protective film 611. The film formation conditions were SiH ₄ / NH ₃ / N ₂ = 180/480/2000 sccm, pressure 1500 mtorr, substrate temperature 320 ° C., and RF 1700 W.

  Further, in order to protect the heater from cavitation due to ink bubbling, 2300 liters of Ta was deposited and patterned by sputtering to form a cavitation resistant film 612.

  In order to increase the adhesion of the resin nozzle and to protect the back surface from the alkali etchant, a polyetheramide resin film (HIMAL manufactured by Hitachi Chemical Co., Ltd.) 613 having a high corrosion resistance was formed by applying and baking 2 μm. Thereby, the heater part and the ink supply port part were exposed by patterning as shown in FIG.

  Polymethylisopropenyl ketone (Tokyo Ohka ODUR-1010) as a photosensitive resin was applied by 20 μm and patterned to form an ink flow path forming material 614 as shown in FIG. 15 (9).

  Furthermore, 10 μm of photosensitive resin 615 shown in Table 1 was applied and patterned to form ink discharge ports 316 as shown in FIG.

ノズル形成面側を保護するために、ゴム系レジスト（東京応化製ＯＢＣ）で保護膜６１７を形成した。ノズル形成された裏面のＳｉＯ_２をパターンニングして、インク供給口開口部６１８を形成した。この時のパターンは、図１０のように表面の犠牲層とは鏡像関係になるような平行四辺形にした。そして、供給口間にハリに相当する部分の幅を１２０μｍ設けた。

In order to protect the nozzle forming surface side, a protective film 617 was formed with a rubber resist (OBC manufactured by Tokyo Ohka Kogyo Co., Ltd.). The ink supply port opening 618 was formed by patterning the SiO ₂ on the back surface where the nozzle was formed. The pattern at this time was a parallelogram having a mirror image relationship with the surface sacrificial layer as shown in FIG. And the width | variety of the part equivalent to a tension | gap was provided 120 micrometers among supply ports.

  Next, a non-penetrating etching lead hole 619 was opened with a YAG laser in a portion adjacent to the narrow angle of the parallelogram window of the ink supply port pattern portion on the back surface. At this time, the diameter of the hole was 30 to 35 μm, and the depth was 440 to 550 μm.

  This substrate was immersed in a 22% TMAH aqueous solution and anisotropically etched. The etchant temperature was 83 ° C. and the etching time was 7 hours 30 minutes. This was an overetching time of 10% with respect to the time for just etching the thickness of the substrate of 630 μm.

  The etching proceeds to the AlCu sacrificial layer as shown in FIG. 17 (15), and stops in front of the etching stop layer 606. At this time, there was no crack in the etching stop layer, and no penetration of the etching solution into the flow path forming resin layer or the nozzle portion was observed.

  The cross section of the groove portion at this time has a structure surrounded by the Si (111) surface as shown in FIG. 21, and the vertex 807 of the groove portion is formed 20 μm below the substrate surface.

Next, as shown in FIG. 17 (16), SiN in the etching stop layer was removed by the CDE method. The etching conditions were CF ₄ / O ₂ / N ₂ = 300/250/5 sccm, RF 800 W, and pressure 250 mtorr.

  After immersion in methyl isobutyl ketone as shown in FIG. 18 (18), the protective film is removed by applying ultrasonic waves in xylene, and the resin 614 is removed by applying ultrasonic waves in methyl lactate to form an ink flow path. An ink jet recording head was completed.

  Using this ink jet recording head, when ejected droplets are 5.5 pl, the maximum ejection frequency is 12 KHz, and high-quality printed matter free from printing blur, density unevenness, and non-ejection of ink can be obtained over the entire 80 mm width. It was.

It is the schematic which shows the principal part of the board | substrate of the inkjet recording head by this invention. It is a figure which shows the board | substrate structure of the conventional inkjet recording head. It is sectional drawing of the board | substrate in the middle of the process leading to this invention. It is a figure which shows the elasticity structure by this invention. It is sectional drawing of the board | substrate in the middle of the process of the conventional inkjet recording head. It is a figure which shows the elasticity structure of the conventional inkjet recording head. FIG. 6 is a diagram illustrating a tension position and a limit response frequency characteristic of an ink jet recording head as a result of an experiment related to the present invention. It is a figure which shows the limit response frequency characteristic of the inkjet recording head which remove | eliminated the upper part of the elasticity by the experimental result regarding this invention. It is a figure which shows the planar shape of a sacrificial layer. It is a figure which shows the planar shape of an ink supply pattern. 1 is an overhead view of an inkjet recording head substrate according to the present invention. 1 is a cross-sectional view of an ink jet recording head substrate according to the present invention. It is a figure which shows the process flow of the inkjet recording head by this invention. FIG. 14 is a diagram illustrating a process flow of the ink jet recording head according to the present invention, following FIG. 13. FIG. 15 is a diagram illustrating a process flow of the ink jet recording head according to the present invention, following FIG. 14. FIG. 16 is a diagram illustrating a process flow of the ink jet recording head according to the present invention, following FIG. 15. FIG. 17 is a diagram illustrating a process flow of the ink jet recording head according to the present invention, following FIG. 16. FIG. 18 is a diagram illustrating a process flow of the ink jet recording head according to the present invention, following FIG. 17. FIG. 19 (19) is a plan view showing a sacrificial layer pattern in the silicon substrate shown in FIG. 13 (2). FIG. 19 (20) is a plan view of the silicon substrate in the step of FIG. 16 (13). It is the cross-sectional shape of the elasticity formed when a sacrificial layer space | interval is narrow. 3 is a cross-sectional shape of the elasticity of the ink jet recording head according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Ink discharge port 102 Liquid chamber wall 103 Ink supply port 104 Hari 105 Nozzle filter 201 Ink discharge port 202 Liquid chamber wall 203 Ink supply port 204 Hari 205 Nozzle filter 301 Silicon substrate 302 Ink supply port opening 303 SiO ₂ (Back mask unit) )
304 Sacrificial layer 305 Sacrificial layer interval 306 Alignment 307 Si (111) surface 308 Alignment top 401 Silicon substrate 402 Ink supply port opening 403 SiO ₂ (back surface mask)
404 Sacrificial layer 405 Sacrificial layer interval 406 Harm 407 Si (111) surface 501 Silicon substrate 502 Harm 503 Heater 504 Electrode 505 Ink discharge port 601 Si substrate 602 Insulating film 603 Ink supply port pattern 604 Lower layer wiring 605 Sacrificial layer 606 Etching stop layer 607 Interlayer insulating film 608 Contact hole 609 Heater 610 Upper layer wiring 611 Heater protective film 612 Anti-cavitation film 613 Polyetheramide resin film 614 Flow path forming resin 615 Nozzle forming resin 616 Ink discharge port 617 Etching protective film 618 Ink supply port pattern 619 Laser processing Lead hole 620 Ink flow path 701 Silicon substrate 702 Harness 703 Torsion top portion 704 SiO ₂ (Back side mask portion)
801 Si 802 Si (111) surface 803 Si (111) surface 804 Si (111) surface 805 Si (111) surface 806 Si (111) surface

Claims (8)

  A silicon single crystal substrate is provided with an ink discharge pressure generating element, and a discharge port is arranged on the plate side facing the ink discharge pressure generating element, generating bubbles in the ink and discharging the ink vertically to the discharge port substrate In the inkjet recording head, a plurality of ink supply ports are continuously arranged in the longitudinal direction on the substrate, and the upper surface of the gap between the continuous ink supply ports is a crystal plane with the (111) orientation as the main surface An ink jet recording head characterized by being formed on a surface surrounded by.   2. The ink jet recording head according to claim 1, wherein the surface having the (111) orientation as a main surface has a surface partially including an error of less than 15 degrees.   2. The ink jet according to claim 1, wherein the vertices surrounded by the surface having the (111) orientation as the main surface are formed at a position lower than the substrate surface on which the ink discharge pressure generating element is formed. Recording head.   2. The ink jet recording head according to claim 1, wherein a side surface portion of the tension is surrounded by a surface having a (111) orientation as a main surface.   In a method for manufacturing a substrate for an ink jet recording head in which a through hole is formed as an ink supply port on a silicon substrate, etching can be selectively performed on an ink supply port forming portion on the surface of the silicon substrate, and the ink supply port on the back surface of the substrate is opposed Providing an adjacent sacrificial layer close to the substrate surface so that the (111) plane appearing during anisotropic etching is in contact with the substrate surface, and etching resistance so as to cover the sacrificial layer on the silicon substrate A step of forming a passivation layer having an etching mask, a step of providing an etching mask opening separated so as to leave a part of the back surface of the silicon substrate corresponding to the sacrifice layer, and the sacrifice layer from the opening. Etching the substrate by crystal axis anisotropic etching until the surface is exposed, and from the portion exposed by the etching step, Etching to remove the sacrificial layer, etching the upper part of the trench until it becomes lower than the substrate surface, and stopping the upper part of the trench at the (111) plane; and removing the passivation layer to form an ink supply port. A method for manufacturing a substrate for an ink jet recording head.   6. The method of manufacturing a substrate for an ink jet recording head according to claim 5, wherein a distance between the adjacent sacrificial layers is 2 μm or more and less than 20 μm.   6. The method of manufacturing a substrate for an ink jet recording head according to claim 5, wherein the upper part of the groove is formed by colliding with a (111) surface formed by etching from a sacrificial layer.   2. The ink jet recording head according to claim 1, wherein the silicon substrate is a Si (110) substrate.

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