Liquid dispensing substrate, liquid dispensing head, and method for manufacturing the liquid dispensing substrate
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- CANON KK
- Filing Date
- 2024-12-04
- Publication Date
- 2026-06-16
Smart Images
Figure 2026097109000001_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to a liquid ejection substrate, a liquid ejection head, and a method for manufacturing a liquid ejection substrate.
Background Art
[0002] Patent Document 1 discloses a liquid ejection head (liquid ejection substrate) including a through-substrate (flow path forming substrate) having through-holes (flow paths). In Patent Document 1, the inner wall surface (inner peripheral surface) of the through-holes penetrating from the first surface to the second surface corresponding to the back side of the first surface of this through-substrate is covered with a protective film (functional layer). Thereby, in the liquid ejection head of Patent Document 1, it is possible to suppress the resin material contained in the through-substrate from dissolving into the liquid passing through the through-holes.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] However, in the liquid ejection head of Patent Document 1, there is room for further improving the adhesion between the flow path forming substrate and the functional layer in order to obtain sufficient protective performance in the functional layer.
[0005] Therefore, an object of the present disclosure is to provide a liquid ejection substrate capable of further improving the adhesion between the flow path forming substrate and the functional layer.
Means for Solving the Problems
[0006] A liquid discharge substrate for discharging liquid is characterized by comprising: a channel-forming substrate having a first surface, a second surface facing the opposite direction to the direction the first surface faces, and a channel configured to penetrate from the first surface to the second surface and allow liquid to flow through it; a first functional layer covering the second surface and the inner circumferential surface of the channel; and a second functional layer covering the first functional layer formed on the second surface of the channel-forming substrate. [Effects of the Invention]
[0007] The liquid discharge substrate of this disclosure makes it possible to further improve the adhesion between the channel-forming substrate and the functional layer. [Brief explanation of the drawing]
[0008] [Figure 1] A schematic perspective view of a liquid dispensing device applicable to one embodiment. [Figure 2] A diagram illustrating a liquid dispensing head in one embodiment. [Figure 3] A diagram illustrating a liquid dispensing substrate in one embodiment. [Figure 4] A diagram showing a comparative example of a liquid dispensing substrate. [Figure 5] A diagram illustrating the manufacturing method of a liquid dispensing substrate. [Figure 6] A diagram showing a modified liquid dispensing substrate. [Figure 7] A diagram showing a modified liquid dispensing substrate. [Modes for carrying out the invention]
[0009] [First Embodiment] <Liquid discharge device 100> Figure 1 is a schematic perspective view of a liquid dispensing device 100 that can be applied to this embodiment.
[0010] As shown in Figure 1, the liquid dispensing device 100 includes a one-pass type liquid dispensing head 101 that moves the recording medium P in one pass and records an image on the recording medium P, and a transport device 102 for transporting the recording medium P.
[0011] The liquid ejection head 101 has multiple ejection ports 5 (see Figure 2, etc.) arranged across the side corresponding to the entire width (length in the X direction) of the recording medium P, for ejecting liquid (for example, ink).
[0012] In this embodiment, the liquid ejection head 101 corresponds to four colors: cyan (C), magenta (M), yellow (Y), and black (K). Specifically, the liquid ejection head 101 includes a first liquid ejection head 101Ca and a second liquid ejection head 101Cb, which correspond to cyan (C) ink. The liquid ejection head 101 includes a third liquid ejection head 101Ma and a fourth liquid ejection head 101Mb, which correspond to magenta (M) ink. The liquid ejection head 101 includes a fifth liquid ejection head 101Ya and a sixth liquid ejection head 101Yb, which correspond to yellow (Y) ink. The liquid ejection head 101 includes a seventh liquid ejection head 101Ka and an eighth liquid ejection head 101Kb, which correspond to black (K) ink.
[0013] The recording medium P is transported in the direction of arrow A by the transport device 102. Recording is performed on the recording medium P by the liquid discharge head 101.
[0014] Note that the liquid dispensing device 100 shown in Figure 1 is merely an example. The liquid dispensing device 100 may be configured to accommodate a liquid dispensing head 101 of any form. For example, the liquid dispensing head 101 may be configured to dispense only one type of ink, or it may be configured to dispense more than the four types of ink described above.
[0015] <Liquid dispensing head 101> Figure 2 is a perspective view showing one liquid dispensing head 101 of any single color from the liquid dispensing heads 101 shown in Figure 1. Note that in Figure 2, the liquid dispensing head 101 is shown in an inverted position compared to the liquid dispensing head 101 shown in Figure 1.
[0016] As shown in FIG. 2, the liquid ejection head 101 includes a head body 4. Inside the head body 4, an electric substrate (not shown) for supplying the power and signals necessary for ejecting the liquid is provided. The head body 4 is provided with a plurality of liquid ejection substrates 21 capable of ejecting the liquid. In the present embodiment, four liquid ejection substrates 21 are provided.
[0017] Each of the plurality of liquid ejection substrates 21 includes terminals (not shown). The terminals and the above-described electric substrate are connected via wiring (not shown). Thereby, it becomes possible to supply the power and signals necessary for ejecting the liquid from the electric substrate to the energy generating element 1 (see FIG. 3(b)) that generates the energy for ejecting the liquid.
[0018] A plurality of ejection ports 5 are formed in each liquid ejection substrate 21. The liquid ejected from the liquid ejection head 101 is supplied from a liquid tank (not shown) for storing the liquid to the liquid ejection substrate 21 through a common supply port (not shown) of the head body 4. On the ejection port surface of the liquid ejection substrate 21 (the surface facing upward in FIG. 2), a row of ejection ports 5 are arranged along the X direction, thereby forming a row of ejection ports.
[0019] Also, on the ejection port surface, a plurality of rows of ejection ports are formed along the Y direction that intersects (orthogonal in the present embodiment) the X direction. The ejection ports 5 formed at the ends in the X direction are arranged so as to overlap with the ejection ports 5 of another liquid ejection substrate 21 along the Y direction. By arranging each liquid ejection substrate 21 in this way, it becomes possible to realize recording by a long row of ejection ports.
[0020] FIG. 3(a) is a schematic cross-sectional perspective view of the liquid ejection substrate 21.
[0021] As shown in FIG. 3(a), the liquid ejection substrate 21 includes a flow path forming substrate 10 in which a flow path 2 is formed, and an ejection port forming substrate 50 in which the ejection ports 5 are formed.
[0022] The channel-forming substrate 10 is constructed by forming a device layer 11 on the upper surface of a silicon substrate 12 containing silicon, which includes a silicon layer, a metal film, and an insulating film. In addition to the discharge port 5, the discharge port forming substrate 50 has a pressure chamber 20 that receives pressure when liquid is discharged.
[0023] Figure 3(b) is a schematic cross-sectional view of the liquid discharge substrate 21 along the X direction.
[0024] As shown in Figure 3(b), a first functional layer 31, which has the function of protecting the channel forming substrate 10, and a second functional layer 41, which has the function of protecting the first functional layer 31, are formed between the discharge port forming substrate 50 and the channel forming substrate 10.
[0025] With the lower surface of the discharge port forming substrate 50 fixed to the upper surface of the device layer 11, the flow path 2 is formed to penetrate the main body of the flow path forming substrate 10 along the Z direction. With the lower surface of the discharge port forming substrate 50 fixed to the upper surface of the second functional layer 41, the flow path 2 is connected to the pressure chamber 20. In the discharge port forming substrate 50, the pressure chamber 20 is connected to the discharge port 5.
[0026] An energy generating element 1 is provided in the device layer 11. The energy generating element 1 is provided at a position corresponding to the discharge port 5. In this embodiment, a heater is used as the energy generating element 1.
[0027] When the heater is heated while the pressure chamber 20 is filled with liquid, the liquid inside the pressure chamber 20 undergoes film boiling. The foaming energy from this film boiling is used to discharge the liquid from the discharge port 5. Thus, in the liquid discharge substrate 21 of this embodiment, when liquid is discharged, the liquid is supplied in the order of flow path 2, pressure chamber 20, and discharge port 5.
[0028] The first functional layer 31 is configured to have resistance to liquids (e.g., ink) (e.g., ink resistance) and covering properties for covering the channel-forming substrate 10. For example, it is preferable that the first functional layer 31 be formed as a metal oxide film containing at least one of Ti, Zr, Hf, V, Nb, and Ta. With this configuration, the first functional layer 31 can achieve both liquid contact and covering properties.
[0029] The first functional layer 31 is formed to continuously cover the lower surface of the channel-forming substrate 10, the inner circumferential surface of the channel 2, and the upper surface of the channel-forming substrate 10. This configuration makes it possible to suppress the dissolution of components of the channel-forming substrate 10 into the liquid and the erosion of the channel-forming substrate 10 by the liquid. Furthermore, it is possible to ensure a sufficient contact area with the channel-forming substrate 10.
[0030] However, the first functional layer 31 does not cover the entire upper surface of the channel-forming substrate 10. The first functional layer 31 is not formed at the position corresponding to the energy generating element 1 on the upper surface of the channel-forming substrate 10. This is because the presence of the first functional layer 31 at this position would hinder the transfer of energy generated by the energy generating element 1 to the liquid.
[0031] In this embodiment, with the discharge port forming substrate 50 fixed to the flow channel forming substrate 10, the end portion 31a of the first functional layer 31 is formed outside the discharge port forming substrate 50. By forming the end portion 31a of the first functional layer 31 at a position relatively far from the discharge port 5 in this way, it becomes more difficult for liquid to penetrate to the interface between the device layer 11 and the first functional layer 31, thereby improving the adhesion of the first functional layer 31 to the device layer 11.
[0032] As described above, the first functional layer 31 is formed in such a way that sufficient adhesion to the channel-forming substrate 10 can be ensured. However, for some reason, the first functional layer 31 may peel off from the channel-forming substrate 10. To prevent such a situation, in this embodiment, a second functional layer 41 is formed to protect the first functional layer 31.
[0033] In this embodiment, the second functional layer 41 is formed to cover the first functional layer 31 that covers the upper surface of the channel forming substrate 10 and the first functional layer 31 that covers the inner circumferential surface of the channel 2. However, inside the channel 2, the second functional layer 41 is formed to cover the first functional layer 31 formed near the exit of the channel 2, but not to cover the first functional layer 31 formed near the entrance of the channel 2. In this way, the first functional layer 31 is formed over the entire inside of the channel 2, but the second functional layer 41 is not formed over the entire inside of the channel 2. That is, the first functional layer 31 is formed over the entire inside of the channel 2, but the second functional layer 41 is formed over a part of the inside of the channel 2.
[0034] Furthermore, the position in the Y direction at the end 41a of the second functional layer 41 aligns with the position in the Y direction at the end 31a of the first functional layer 31. With this configuration, on the upper surface of the flow channel forming substrate 10, the end 41a of the second functional layer 41 and the end 31a of the first functional layer 31 are formed at a distance from the discharge port 5, making it difficult for liquid to adhere to them. Therefore, since the penetration of liquid into the interface between the second functional layer 41 and the first functional layer 31 is suppressed, the adhesion of the second functional layer 41 to the first functional layer 31 is ensured. Thus, the formation patterns of the first functional layer 31 and the second functional layer 41 are different from each other.
[0035] Furthermore, the second functional layer 41 has resistance to liquids and adhesion to the first functional layer 31.
[0036] In this embodiment, the second functional layer 41 is a film made of a Si compound selected from the group consisting of SiC, SiOC, SiCN, SiCN, SiO, SiN, and SiCN. However, the material constituting the second functional layer 41 is not limited to the materials described above, as long as it has resistance to liquids and adhesion to the first functional layer 31.
[0037] To improve the adhesion of the second functional layer 41 to the first functional layer 31, it is effective to increase the stress by compressing the film.
[0038] Here, film stress refers to the internal stress of the film. Generally, the internal stress of a film is evaluated by measuring the warpage of the structure before the film is formed on the structure, and the warpage of the structure after the film is formed on the structure, and is expressed as force per unit area. When measuring the stress of a film formed on a structure, the film stress can be detected by cutting out the part of the structure on which the film is formed and measuring the amount of deformation of the structure before and after the film is removed. Alternatively, if the structure is crystalline, the film stress can also be detected by evaluating the strain that the stress exerts on the crystal lattice using X-ray diffraction or the like.
[0039] In this embodiment, if the stress in the first functional layer 31 is tensile and the stress in the second functional layer 41 is compressive, the adhesion of the second functional layer 41 to the first functional layer 31 can be improved.
[0040] On the other hand, if the stress in the first functional layer 31 is compressive, and the stress in the second functional layer 41 is also compressive and greater than that of the first functional layer 31, the adhesion of the second functional layer 41 to the first functional layer 31 can be improved.
[0041] However, if the stress value of the second functional layer 41 is too large, and the channel forming substrate 10 bends significantly for some reason, a problem may occur in the adhesion of the second functional layer 41 to the first functional layer 31.
[0042] Therefore, in this embodiment, the second functional layer 41 is configured such that its stress value falls within a predetermined range. For example, it is preferable that the stress value of the second functional layer 41 is between 100 MPa and 600 MPa. It is more preferable that the stress value of the second functional layer 41 is between 200 MPa and 400 MPa. With this configuration, even if the channel forming substrate 10 is significantly bent, the adhesion of the second functional layer 41 to the first functional layer 31 can be ensured.
[0043] Furthermore, it is preferable that the Young's modulus of the material of the second functional layer 41 is greater than that of the material of the first functional layer 31. For example, it is preferable that the bulk Young's modulus of the material used for the second functional layer 41 be 300 GPa or more. It is even preferable that the bulk Young's modulus of the material used for the second functional layer 41 be 400 GPa or more. In this way, by increasing the Young's modulus of the material of the second functional layer 41, deformation of the second functional layer 41 is suppressed, and thus the adhesion of the second functional layer 41 to the first functional layer 31 can be ensured.
[0044] Furthermore, it is preferable that the thickness (length in the Z direction) of the second functional layer 41 is greater than the thickness of the first functional layer 31. This is because the greater the force required to bend the second functional layer 41, the more difficult it becomes to physically detach the first functional layer 31 from the channel-forming substrate 10.
[0045] If the second functional layer 41 is cut into a thin plate shape and deformed with a predetermined curvature, the stress value of the second functional layer 41 will be proportional to the thickness of the second functional layer 41. In other words, the greater the thickness of the second functional layer 41, the greater the force required to deform it.
[0046] For example, the thickness of the second functional layer 41 is preferably 1.5 times or more the thickness of the first functional layer 31. It is more preferable that the thickness of the second functional layer 41 is twice or more the thickness of the first functional layer 31. By making the thickness of the second functional layer 41 greater than the thickness of the first functional layer 31, the rigidity of the second functional layer 41 is improved, and thus the adhesion of the first functional layer 31 to the channel-forming substrate 10 can also be improved.
[0047] Furthermore, as will be described in more detail later, it is preferable that the channel-forming substrate 10 and the first functional layer 31 contain the same material. With this configuration, the interface between the channel-forming substrate 10 and the first functional layer 31 can be made to adhere more firmly.
[0048] Furthermore, it is preferable that the first functional layer 31 and the second functional layer 41 contain the same material. With this configuration, the interface between the first functional layer 31 and the second functional layer 41 can be more firmly fixed.
[0049] Furthermore, it is preferable that the second functional layer 41 and the discharge port forming substrate 50 contain the same material. This configuration allows for a stronger fixation of the interface between the second functional layer 41 and the discharge port forming substrate 50.
[0050] In this way, by improving the quality of the second functional layer 41 and the degree of freedom in selecting materials, the adhesion of the discharge port forming substrate 50 to the second functional layer 41 can also be improved.
[0051] The configuration in which the nozzle-forming substrate 50 is fixed to the second functional layer 41 is particularly preferable when shrinking of the liquid ejection substrate 21, increasing the density of the energy generating element 1, using a new type of ink, and circulating the ink.
[0052] Figure 3(c) is a schematic cross-sectional view of the liquid discharge substrate 21 along the Y direction.
[0053] As shown in Figure 3(c), even when the liquid discharge substrate 21 is viewed along the Y direction, the second functional layer 41 covers the first functional layer 31. In this way, even if the second functional layer 41 covers only a part of the first functional layer 31, it is possible to protect the first functional layer 31. That is, the second functional layer 41 may cover only the front surface (viewed along the X direction) of the first functional layer 31, or it may cover only the side surface (viewed along the Y direction) of the first functional layer 31.
[0054] In the example shown in Figure 3(c), a cross-section of the side surface of the channel-forming substrate 10 is shown, but the first functional layer 31 and the second functional layer 41 may be formed so as to cover the side surface of the channel-forming substrate 10. Even with this configuration, the channel-forming substrate 10 is sufficiently protected by the first functional layer 31. The first functional layer 31 is adequately protected by the second functional layer 41.
[0055] Figure 3(d) is a schematic plan view of a liquid discharge substrate 21 applicable to this embodiment. In Figure 3(d), the discharge port forming substrate 50 is shown by a dashed line.
[0056] As shown in Figure 3(d), even when the liquid discharge substrate 21 is viewed from above, the first functional layer 31 (see Figure 3(b), etc.) is covered by the second functional layer 41.
[0057] Figure 4 shows a comparative example of the liquid discharge substrate 21. In Figure 4, a liquid discharge substrate 21 without the second functional layer 41 is shown in order to explain the effect of the second functional layer 41 (see Figure 3(b), etc.).
[0058] As shown in Figure 4, in this comparative example, the second functional layer 41 is not formed, and therefore the first functional layer 31 is not protected.
[0059] An example of a method for forming the first functional layer 31 is the known atomic layer deposition (ALD) method. The ALD method has excellent coverage but tends to have poor adhesion. This is because the film is formed by physical adsorption in the ALD method.
[0060] Therefore, in the technology disclosed herein, a second functional layer 41 (see Figure 3(b), etc.) is formed on the first functional layer 31 to protect the first functional layer 31. The position where the first functional layer 31 is formed is not particularly limited, but in this embodiment, the second functional layer 41 is formed at the corner 31b of the first functional layer 31. This is because, depending on the configuration of the liquid discharge substrate 21, the corner 31b of the first functional layer 31 may easily peel off from the flow path forming substrate 10.
[0061] Figures 5(a) to 5(f) show an example of a method for manufacturing a liquid discharge substrate 21 that can be applied to this embodiment.
[0062] As shown in Figure 5(a), a channel-forming substrate 10 is prepared by fixing the lower surface of the device layer 11 to the upper surface of the silicon substrate 12. However, at this stage, although the energy generating element 1 is provided and the channel 2 is formed, the first functional layer 31 and the second functional layer 41 have not yet been formed.
[0063] As shown in Figure 5(b), a first functional layer 31 is formed on the channel-forming substrate 10 obtained in Figure 5(a). At this stage, the first functional layer 31 is formed continuously on the upper surface of the device layer 11, the inner circumferential surface of the channel 2, and the lower surface of the silicon substrate 12. The first functional layer 31 is formed in such a way that it does not block the channel 2.
[0064] In this embodiment, the first functional layer 31 is formed by the ALD method. The ALD method can maintain protection for the flow channel 2 compared to other methods. However, the method for forming the first functional layer 31 is not limited to the ALD method, as long as protection for the flow channel 2 can be maintained.
[0065] As shown in Figure 5(c), a second functional layer 41 is formed on the channel-forming substrate 10 obtained in Figure 5(b). At this stage, the second functional layer 41 is formed to cover all of the first functional layer 31 that covers the upper surface of the device layer 11, and a portion of the first functional layer 31 that covers the inner circumferential surface of the channel 2.
[0066] In this embodiment, the second functional layer 41 is formed by plasma chemical vapor deposition (plasma CVD). Other examples of methods capable of forming the second functional layer 41 include sputtering. By forming the second functional layer 41 using plasma CVD or sputtering, the adhesion between the second functional layer 41 and the discharge port forming substrate 50 can be improved compared to other methods.
[0067] In particular, when a mask pattern is formed at high density, it is preferable to use plasma CVD or sputtering. This is because using plasma CVD or sputtering makes it easier to secure an area where the second functional layer 41 and the nozzle-forming substrate 50 are in close contact, compared to other methods. However, the method for forming the second functional layer 41 is not limited to plasma CVD or sputtering, as long as adhesion to the first functional layer 31 can be ensured.
[0068] As shown in Figure 5(d), a resist 6 is formed on the channel-forming substrate 10 obtained in Figure 5(c) using a known method, and the resist 6 is exposed and developed to form a predetermined resist mask. An example of a method for forming the resist 6 is to laminate a dry film of the resist 6 onto the channel-forming substrate 10. However, the example of a method for forming the resist 6 is not limited to this.
[0069] At this stage of this embodiment, a resist mask is formed to remove the second functional layer 41 and the first functional layer 31, which are formed at the positions corresponding to the energy generating element 1.
[0070] Furthermore, it is preferable to form a single resist mask common to the second functional layer 41 and the first functional layer 31. This method reduces the number of steps required to form the resist mask compared to forming a resist mask individually for each of the second functional layer 41 and the first functional layer 31.
[0071] As shown in Figure 5(e), the channel-forming substrate 10 obtained in Figure 5(d) is etched to remove the second functional layer 41 formed at the position corresponding to the energy generating element 1.
[0072] In the etching process of this embodiment, the first functional layer 31 is used as a stop layer. By using the first functional layer 31 as a stop layer, damage to the device layer 11 can be reduced while improving the flexibility of the process. Dry etching is an example of a method for removing the second functional layer 41. However, the method for removing the second functional layer 41 is not limited to dry etching, as long as it is appropriate for the material of the second functional layer 41.
[0073] As shown in Figure 5(f), the channel-forming substrate 10 obtained in Figure 5(e) is etched to remove the first functional layer 31 formed at the position corresponding to the energy generating element 1. Wet etching is an example of a method for removing the first functional layer 31. Compared to other methods, wet etching reduces damage to the device layer 11 and makes it easier to control the work. However, the method for removing the first functional layer 31 is not limited to wet etching, as long as the method is appropriate for the material of the first functional layer 31.
[0074] As shown in Figure 5(g), the resist 6 is peeled off from the channel-forming substrate 10 obtained in Figure 5(f) using a known method.
[0075] As shown in Figure 5(h), the discharge port forming substrate 50 is formed on the channel forming substrate 10 obtained in Figure 5(g) using a known method.
[0076] The above describes a manufacturing method that can be applied to this embodiment.
[0077] <Examples> The following describes an example of the manufacturing method for the liquid discharge substrate 21 shown in Figure 5(h).
[0078] First, a silicon substrate 12 was prepared, and a device layer 11 containing the energy generating element 1 was formed on the upper surface of the silicon substrate 12.
[0079] Next, a channel 2 was formed in the channel-forming substrate 10, which consists of a silicon substrate 12 and a device layer 11.
[0080] Next, a TiO film was formed as the first functional layer 31 using the ALD method. The thickness of the TiO film was 50 nm. The tensile stress of the TiO film was 300 MPa.
[0081] Next, a SiC film was formed as the second functional layer 41 using plasma CVD. The thickness of this SiC film was 100 nm. The compressive stress of this SiC film was 300 MPa. According to literature values, the Young's modulus of the TiO2 material used was 290 GPa, and the Young's modulus of the SiC material used was 440 GPa. Thus, the Young's modulus of the second functional layer 41 was greater than that of the first functional layer 31.
[0082] Next, a resist 6 was formed on the channel-forming substrate 10. A single resist mask was formed on the resist 6, which is used in common for etching the SiC film and etching the TiO film.
[0083] Next, the SiC film was patterned. Dry etching was performed during this patterning process. In this dry etching, a TiO film was used as a stop layer.
[0084] Next, the TiO film was patterned. Wet etching was used for this patterning process.
[0085] Next, I removed Resist 6.
[0086] Next, the discharge port forming substrate 50 was formed.
[0087] The above is a description of this embodiment.
[0088] <Comparative Example> Below, we will describe a comparative example of the manufacturing method of the liquid discharge substrate 21 shown in Figure 4.
[0089] First, a silicon substrate 12 was prepared, and a device layer 11 containing the energy generating element 1 was formed on the upper surface of the silicon substrate 12.
[0090] Next, a channel 2 was formed in the channel-forming substrate 10, which consists of a silicon substrate 12 and a device layer 11.
[0091] Next, a TiO film was formed as the first functional layer 31, in the same manner as in the example.
[0092] Next, a resist 6 was formed on the channel-forming substrate 10. A resist mask having the same pattern as in the example was formed on the resist 6.
[0093] Next, the TiO film was patterned. Wet etching was used for this patterning process.
[0094] Next, I removed Resist 6.
[0095] Next, the discharge port forming substrate 50 was formed.
[0096] The liquid ejection substrates obtained by the manufacturing method of the example and the liquid ejection substrates obtained by the manufacturing method of the comparative example were evaluated by immersion in ink. The results of the evaluation showed that the edges of the first functional layer 31 of the liquid ejection substrate in the comparative example were more prone to lifting than the edges of the first functional layer 31 of the liquid ejection substrate in the example. Therefore, it was shown that the adhesion of the first functional layer 31 to the channel forming substrate 10 in the example was improved compared to the adhesion of the first functional layer 31 to the channel forming substrate 10 in the comparative example.
[0097] As explained above, in this embodiment, since the second functional layer 41 is formed, the thickness of the functional layer protecting the channel-forming substrate 10 is increased compared to the case in which the second functional layer 41 is not formed. In other words, in this embodiment, the rigidity of the functional layer protecting the channel-forming substrate 10 is increased compared to the case in which the second functional layer 41 is not formed. Therefore, the risk of the first functional layer 31 peeling off can be reduced compared to the case in which the second functional layer 41 is not formed.
[0098] Therefore, the liquid discharge substrate of this embodiment can improve the adhesion between the channel-forming substrate and the functional layer.
[0099] [First modified example in the first embodiment] Figure 6(a) is a schematic cross-sectional view of the liquid discharge substrate 21 in the first modified example.
[0100] Figure 6(b) is a schematic plan view of the liquid discharge substrate 21 in the first modified example. In Figure 6(b), for ease of explanation, the discharge port forming substrate 50 is shown with a dashed line. In the following plan views as well, the discharge port forming substrate 50 is shown with a dashed line, similar to Figure 6(b).
[0101] As shown in Figures 6(a) and 6(b), the first functional layer 31 and the second functional layer 41 may be formed on the upper surface of the device layer 11 only inside the discharge port forming substrate 50. In this modified example, on the upper surface of the first functional layer 31, only the area near the outlet of the flow path 2 is covered by the second functional layer 41.
[0102] For example, when viewing a cross-section of the liquid ejection substrate 21 along the X direction (see Figure 6(a)), the length in the Y direction of the contact portion between the first functional layer 31 and the second functional layer 41 is 0.1 μm or more. It is more preferable that the length in the Y direction of the contact portion between the first functional layer 31 and the second functional layer 41 is 1.0 μm or more. It is even more preferable that the length in the Y direction of the contact portion between the first functional layer 31 and the second functional layer 41 is 5.0 μm or more. This is because the longer the length in the Y direction of the contact portion between the first functional layer 31 and the second functional layer 41, the better the adhesion between the first functional layer 31 and the second functional layer 41.
[0103] This configuration also improves the adhesion between the channel-forming substrate and the functional layer.
[0104] [Second variation in the first embodiment] Figure 6(c) is a schematic cross-sectional view of the liquid discharge substrate 21 in the second modified example.
[0105] Figure 6(d) is a schematic plan view of the liquid discharge substrate 21 in the second modified example.
[0106] As shown in Figures 6(c) and 6(d), the second functional layer 41 may be configured to cover the corners of the first functional layer 31 from the inner circumferential surface to the upper surface of the flow channel 2 near the outlet of the flow channel 2.
[0107] In this configuration, the interface between the first functional layer 31 and the device layer 11 is covered by the second functional layer 41, thereby suppressing the penetration of liquid into the interface between the first functional layer 31 and the device layer 11. In this configuration, the surface of the liquid discharge substrate 21 facing the X direction may also be covered by the second functional layer 41. In the following modified examples, the surface of the liquid discharge substrate 2 facing the X direction may also be covered by the second functional layer 41.
[0108] This configuration also improves the adhesion between the channel-forming substrate and the functional layer.
[0109] [Third modified example in the first embodiment] Figure 6(e) is a schematic cross-sectional view of the liquid discharge substrate 21 in the third modified example.
[0110] Figure 6(f) is a schematic plan view of the liquid discharge substrate 21 in the third modified example.
[0111] As shown in Figures 6(e) and 6(f), in this modified example, the second functional layer 41 covers the entire first functional layer 31 inside the channel 2. Furthermore, the second functional layer 41 covers the upper surface of the channel-forming substrate 10 over a wider area than the first functional layer 31.
[0112] For example, when the first functional layer 31 is made of resin, the adhesion of the nozzle-forming substrate 50 to the first functional layer 31 becomes an issue. Specifically, when the first functional layer 31 is made of epoxy, silicone, benzocyclobutene, polyimide, etc., the adhesion of the nozzle-forming substrate 50 to the first functional layer 31 becomes an issue.
[0113] Furthermore, if there is a layer at the interface between the channel-forming substrate 10 and the first functional layer 31 that is easily dissolved by ink, and the new ink penetrates into this layer, the adhesion of the first functional layer 31 to the channel-forming substrate 10 becomes a problem.
[0114] For example, if the ink contains a new type of surfactant, there is a risk that the ink may penetrate the interface between the channel-forming substrate 10 and the first functional layer 31. In addition, if an ink is used to directly etch patterns onto metals or the like, there is a risk that the ink may penetrate the interface between the channel-forming substrate 10 and the first functional layer 31. Furthermore, if an acidic or alkaline ink, or an ink used to directly print circuits, is used, the adhesion of the first functional layer 31 to the channel-forming substrate 10 becomes a problem.
[0115] Furthermore, when inks that easily penetrate the interface between the nozzle-forming substrate 50 and the first functional layer 31, or inks that easily swell, are used, the adhesion of the first functional layer 31 to the nozzle-forming substrate 50 becomes a problem. For example, if the ink contains a new type of surfactant or organic solvent, there is a risk that the ink may penetrate the interface between the nozzle-forming substrate 50 and the first functional layer 31. In addition, when the ink is heated or circulated, there is a risk that the ink may penetrate the interface between the nozzle-forming substrate 50 and the first functional layer 31, causing the nozzle-forming substrate 50 or the first functional layer 31 to dissolve.
[0116] However, according to the configuration of this modified example, the interface between the discharge port forming substrate 50 and the first functional layer 31 is covered by the second functional layer 41. This makes it possible to suppress the penetration of liquid into the interface between the discharge port forming substrate 50 and the first functional layer 31.
[0117] Therefore, compared to a configuration in which the interface between the discharge port forming substrate 50 and the first functional layer 31 is not covered, this modified configuration improves the adhesion of the first functional layer 31 to the flow channel forming substrate 10.
[0118] Furthermore, in this modified example, the second functional layer 41 continuously covers the first functional layer 31, which is formed continuously on the lower surface of the silicon substrate 12, the inner circumferential surface of the channel 2, and the upper surface of the device layer 11. By forming the second functional layer 41 so that the second functional layer 41 that protrudes from one of the multiple channel 2s enters into the other channel 2s, the adhesion can be further improved.
[0119] In this way, by having one second functional layer 41 continuously protect the openings of each of the multiple flow paths 2, a larger contact area can be secured.
[0120] Furthermore, in this configuration as well, since the end portion 41a of the second functional layer 41 is formed between the device layer 11 and the discharge port forming substrate 50, the end portion 41a of the second functional layer 41 located on the upper surface of the device layer 11 is protected by the discharge port forming substrate 50.
[0121] This configuration also improves the adhesion between the channel-forming substrate and the functional layer.
[0122] [Fourth modified example in the first embodiment] Figure 6(g) is a schematic cross-sectional view of the liquid discharge substrate 21 in the fourth modified example.
[0123] Figure 6(h) is a schematic plan view of the liquid discharge substrate 21 in the fourth modified example.
[0124] As shown in Figures 6(g) and 6(h), the first functional layer 31 and the second functional layer 41 may be formed between the device layer 11 and the ejection port forming substrate 50, extending partway from the inside of the ejection port forming substrate 50.
[0125] With this configuration, the edges of the first functional layer 31 and the edges of the second functional layer 41 are protected by the discharge port forming substrate 50, thereby suppressing the penetration of liquid into the interface between the device layer 11 and the first functional layer 31.
[0126] Furthermore, as shown in Figure 6(h), one second functional layer 41 may continuously protect the outlets of multiple flow channels 2 formed along the Y direction.
[0127] This configuration also improves the adhesion between the channel-forming substrate and the functional layer.
[0128] [Fifth variation in the first embodiment] Figure 6(i) is a schematic cross-sectional view of the liquid discharge substrate 21 in the fifth modified example.
[0129] Figure 6(j) is a schematic plan view of the liquid discharge substrate 21 in the fifth modified example.
[0130] As shown in Figures 6(i) and 6(j), the first functional layer 31 and the second functional layer 41 may be formed between the device layer 11 and the ejection port forming substrate 50, extending partway from the inside of the ejection port forming substrate 50.
[0131] With this configuration, the edges of the first functional layer 31 and the edges of the second functional layer 41 are protected by the discharge port forming substrate 50, thereby suppressing the penetration of liquid into the interface between the device layer 11 and the first functional layer 31.
[0132] Furthermore, as shown in Figure 6(j), one second functional layer 41 may continuously protect the outlets of multiple flow channels 2 formed along the X direction.
[0133] When the energy generating elements 1 are arranged at a high density and the distance between the two discharge ports 5 in the X direction is short, a configuration in which the second functional layer 41 continuously protects multiple flow paths 2, as in this modified example, is particularly effective.
[0134] For example, the configuration of this modified example is preferable when the distance between the two discharge ports 5 is 40 μm or less. It is more preferable when the distance between the two discharge ports 5 is 20 μm or less. It is even more preferable when the distance between the two discharge ports 5 is 10 μm or less.
[0135] This configuration also improves the adhesion between the channel-forming substrate and the functional layer.
[0136] [Sixth Modification in the First Embodiment] Figure 6(k) is a schematic cross-sectional view of the liquid discharge substrate 21 in the sixth modified example.
[0137] Figure 6(l) is a schematic plan view of the liquid discharge substrate 21 in the sixth modified example.
[0138] As shown in Figures 6(k) and 6(l), in this modified example, the second functional layer 41 covers the corner of the first functional layer 31 from the inner circumferential surface to the upper surface of the flow path 2 near the exit of the flow path 2, and also covers the interface between the device layer 11 and the first functional layer 31.
[0139] With this configuration, the interface between the device layer 11 and the first functional layer 31 is protected by the second functional layer 41, thereby suppressing the penetration of liquid into the interface between the device layer 11 and the first functional layer 31.
[0140] [Second Embodiment] In the first embodiment, a heater was used as the energy generating element 1. However, in this embodiment, a piezoelectric element is used as the energy generating element 1. In this embodiment, the device layer 11 includes a diaphragm (not shown) that deforms in response to the driving of the piezoelectric element. Liquid is discharged when the diaphragm is driven. In the following description, components that are the same as or corresponding to the first embodiment are denoted by the same reference numerals and their descriptions are omitted, and the differences are mainly described.
[0141] Figure 7(a) is a schematic cross-sectional view of the liquid discharge substrate 21 in this embodiment.
[0142] As shown in Figure 7(a), the second functional layer 41 has a configuration that covers the corner of the first functional layer 31 from the inner circumferential surface to the upper surface of the flow channel 2 near the outlet of the flow channel 2.
[0143] This configuration also improves the adhesion between the channel-forming substrate and the functional layer.
[0144] [First variation in the second embodiment] Figure 7(b) is a schematic cross-sectional view of the liquid discharge substrate 21 in this modified example.
[0145] As shown in Figure 7(b), the end 31a of the first functional layer 31 and the end 41a of the second functional layer 41 are located between the device layer 11 and the ejection port forming substrate 50.
[0146] By positioning the end 31a of the first functional layer 31 and the end 41a of the second functional layer 41 inside the discharge port forming substrate 50 and outside the pressure chamber 20, it is possible to suppress the penetration of liquid into the interface between the device layer 11 and the first functional layer 31.
[0147] [Second modified example in the second embodiment] Figure 7(c) is a schematic cross-sectional view of the liquid discharge substrate 21 in this modified example.
[0148] As shown in Figure 7(c), in this modified example, the discharge port forming substrate 50 includes a first layer 50a and a second layer 50b. By stacking multiple layers to form the discharge port forming substrate 50, the functions required for the discharge port forming substrate 50 can be assigned to each layer.
[0149] By stacking multiple layers in this manner to form the discharge port forming substrate 50, the design flexibility of the discharge port forming substrate 50 can be improved. The same applies to the modified example shown in Figure 7(d).
[0150] The lower surface of the second layer 50b is fixed to the upper surface of the device layer 11. By forming the second layer 50b and the device layer 11 using the same material, the process of forming these layers can be simplified.
[0151] For example, if the upper surface of the device layer 11 is made of silicon, the lower surface of the second layer 50b may be made of silicon. Alternatively, if the upper surface of the device layer 11 is made of stainless steel, the lower surface of the second layer 50b may be made of stainless steel. Note that the materials constituting the upper surface of the device layer 11 and the lower surface of the second layer 50b are not limited to silicon or stainless steel.
[0152] The lower surface of the first layer 50a is fixed to the upper surface of the second layer 50b. An outlet 5 is formed in the first layer 50a.
[0153] Furthermore, the end 31a of the first functional layer 31 and the end 41b of the second functional layer 41 are located between the first layer 50a and the second layer 50b. This configuration also helps to suppress the penetration of liquid into the interface between the device layer 11 and the first functional layer 31.
[0154] [Third modified example in the second embodiment] Figure 7(d) is a schematic cross-sectional view of the liquid discharge substrate 21 in this modified example.
[0155] As shown in Figure 7(d), in this modified example, the first functional layer 31 continuously covers the lower surface of the silicon substrate 12, the inner circumferential surface of the flow path 2, the pressure chamber 20, the discharge port 5, and the upper surface (discharge port surface) of the discharge port forming substrate 50.
[0156] The second functional layer 41 covers the first functional layer 31 formed on the discharge port surface from the inside of the discharge port 5.
[0157] Incidentally, the manufacturing process of the liquid ejection substrate 21 includes a dicing process (not shown). According to the configuration of this modified example, after dicing, the edges of the first functional layer 31 and the edges of the second functional layer 41 are located at the edges of the chipped liquid ejection substrate 21.
[0158] Therefore, this configuration also makes it possible to suppress the penetration of liquid into the interface between the device layer 11 and the first functional layer 31.
[0159] [Other embodiments] In the embodiments described above, the stop layer was used only for etching the second functional layer 41, but the stop layer may also be used for etching the first functional layer 31. For example, a film suitable as a stop layer for etching the first functional layer 31 and the second functional layer 41 may be formed on the device layer. Specifically, it is preferable that the film be composed of Ir (iridium) or Pt (platinum). This configuration makes it possible to reduce damage to the device layer during etching and to control the etching process.
[0160] In the embodiments described above, a liquid dispensing device 100 equipped with a line head (page-wide type head) that is long in the page width direction (X direction) of the recording medium was used. However, the technology of this disclosure can also be applied to a liquid dispensing device equipped with a liquid dispensing head that scans in the scanning direction (X direction) that intersects the transport direction (Y direction) of the recording medium P in a plane. That is, the technology of this disclosure can also be applied to so-called serial type liquid dispensing devices.
[0161] This disclosure includes the following configuration and method.
[0162] [Configuration 1] A liquid dispensing substrate for dispensing liquid, A channel-forming substrate having a first surface, a second surface facing the opposite direction to the direction the first surface faces, and a channel configured to penetrate from the first surface to the second surface and allow liquid to flow through it, The second surface and the first functional layer covering the inner circumferential surface of the flow path, A second functional layer covering the first functional layer formed on the second surface of the channel-forming substrate, A liquid dispensing substrate characterized by comprising the above.
[0163] [Configuration 2] The first functional layer continuously covers the second surface and the inner circumferential surface of the flow path. Liquid dispensing substrate as described in Configuration 1.
[0164] [Configuration 3] Inside the flow channel, the second functional layer covers the entirety of the first functional layer. Liquid discharge substrate as described in Configuration 2.
[0165] [Structure 4] The stress in the first functional layer is tensile, The stress in the second functional layer is compression. A liquid dispensing substrate as described in any one of configurations 1 to 3.
[0166] [Composition 5] The stress in the first functional layer is compression, The stress in the second functional layer is compression, The stress value of the second functional layer is greater than the stress value of the first functional layer. A liquid dispensing substrate as described in any one of configurations 1 to 4.
[0167] [Composition 6] The Young's modulus of the material of the second functional layer is greater than that of the material of the first functional layer. A liquid dispensing substrate as described in any one of items 1 to 5 of the configuration.
[0168] [Composition 7] The second functional layer is thicker than the first functional layer. A liquid dispensing substrate as described in any one of items 1 to 6 of the configuration.
[0169] [Structure 8] The first functional layer is a metal oxide film containing at least one of Ti, Zr, Hf, V, Nb, and Ta. The second functional layer is a Si compound selected from the group consisting of SiC, SiOC, SiCN, SiCN, SiO, SiN, and SiON. A liquid dispensing substrate as described in any one of items 1 to 7 of the configuration.
[0170] [Composition 9] When the second surface is viewed from above, one of the second functional layers continuously covers the periphery of the openings of the multiple flow channels. A liquid dispensing substrate as described in any one of items 1 to 8 of the configuration.
[0171] [Configuration 10] When the second surface is viewed from above, one of the first functional layers continuously covers the periphery of the openings of the multiple flow channels. A liquid dispensing substrate as described in any one of items 1 to 9 of the configuration.
[0172] [Composition 11] The system further comprises a discharge port forming substrate having a discharge port for discharging the liquid supplied through the aforementioned flow path, At least one end of the second functional layer is positioned so as not to come into contact with the liquid. A liquid dispensing substrate as described in any one of configurations 1 to 10.
[0173] [Composition 12] The system further comprises a discharge port forming substrate having a discharge port for discharging the liquid supplied through the aforementioned flow path, At least one end of the first functional layer is located in a position that does not come into contact with the liquid. Liquid discharge substrate as described in configuration 11.
[0174] [Composition 13] One end of the first functional layer and one end of the second functional layer are located between the flow channel forming substrate and the discharge port forming substrate. A liquid discharge substrate as described in configuration 11 or 12.
[0175] [Composition 14] Multiple discharge ports are arranged on the discharge port forming substrate along the first direction. With the second surface viewed from above, one of the second functional layers covers the periphery of the openings of the multiple flow channels formed along the first direction. A liquid dispensing substrate as described in any one of items 11 to 13 of the configuration.
[0176] [Composition 15] Multiple discharge ports are arranged on the discharge port forming substrate along the first direction. With the second surface viewed from above, one of the second functional layers covers the periphery of the openings of the multiple flow channels formed along a second direction intersecting the first direction. A liquid dispensing substrate as described in any one of items 11 to 14 of the configuration.
[0177] [Composition 16] The channel-forming substrate has an energy generating element formed at a position opposite the discharge port, which generates energy for discharging liquid from the discharge port. In the channel-forming substrate, the second functional layer is not formed at a position corresponding to the energy generating element. A liquid dispensing substrate as described in any one of items 13 to 15 of the configuration.
[0178] [Composition 17] The energy generating element is a heater. Liquid discharge substrate as described in configuration 16.
[0179] [Composition 18] The energy generating element is a piezoelectric element. Liquid discharge substrate as described in configuration 16.
[0180] [Composition 19] The liquid discharge substrate of configuration 1 is provided, A liquid dispensing head characterized by the following features.
[0181] [Method 20] A method for manufacturing a liquid dispensing substrate that dispenses liquid, A preparation step of preparing a channel-forming substrate having a first surface, a second surface facing the opposite direction to the direction the first surface faces, and a channel configured to penetrate from the first surface to the second surface and allow liquid to flow through it, A first forming step of forming a first functional layer on the second surface and the inner circumferential surface of the flow channel, A second forming step of forming a second functional layer on the first functional layer formed on the second surface of the channel forming substrate, A first etching step in which etching is performed on the second functional layer, A second etching step in which etching is performed on the first functional layer, including, A method for manufacturing a liquid discharge substrate, characterized by the following:
[0182] [Method 21] In the first forming step, the first functional layer is formed by the ALD method. In the second formation step, the second functional layer is formed by plasma CVD or sputtering. Method 20 for manufacturing a liquid discharge substrate.
[0183] [Method 22] In the first etching step and the second etching step, a common mask is used. A method for manufacturing a liquid discharge substrate according to method 20 or 21.
[0184] [Method 23] In the first etching process described above, dry etching is performed. In the second etching step described above, wet etching is performed. Method 22 for manufacturing a liquid discharge substrate.
[0185] [Method 24] In the first etching step, the first functional layer is used as a stop layer. A method for manufacturing a liquid dispensing substrate according to any one of methods 20 to 23.
[0186] [Method 25] The second surface of the channel-forming substrate includes Ir or Pt, In the first etching step, the second surface is used as a stop layer. A method for manufacturing a liquid dispensing substrate according to any one of methods 20 to 24.
[0187] [Method 26] The second surface of the channel-forming substrate includes Ir or Pt, In the second etching step, the second surface is used as a stop layer. A method for manufacturing a liquid dispensing substrate according to any one of methods 20 to 25.
Claims
1. A liquid dispensing substrate for dispensing liquid, A channel-forming substrate having a first surface, a second surface facing the opposite direction to the direction the first surface faces, and a channel configured to penetrate from the first surface to the second surface and allow liquid to flow through it, The second surface and the first functional layer covering the inner circumferential surface of the flow path, A second functional layer covering the first functional layer formed on the second surface of the channel-forming substrate, A liquid dispensing substrate characterized by comprising the above.
2. The first functional layer continuously covers the second surface and the inner circumferential surface of the flow path. The liquid dispensing substrate according to claim 1.
3. Inside the flow channel, the second functional layer covers the entirety of the first functional layer. The liquid dispensing substrate according to claim 2.
4. The stress in the first functional layer is tensile, The stress in the second functional layer is compression. The liquid dispensing substrate according to claim 1.
5. The stress in the first functional layer is compression, The stress in the second functional layer is compression, The stress value of the second functional layer is greater than the stress value of the first functional layer. The liquid dispensing substrate according to claim 1.
6. The Young's modulus of the material of the second functional layer is greater than that of the material of the first functional layer. The liquid dispensing substrate according to claim 1.
7. The second functional layer is thicker than the first functional layer. The liquid dispensing substrate according to claim 1.
8. The first functional layer is a metal oxide film containing at least one of Ti, Zr, Hf, V, Nb, and Ta. The second functional layer described above is a Si compound selected from the group consisting of SiC, SiOC, SiCN, SiOCN, SiO, SiN, and SiON. The liquid dispensing substrate according to claim 1.
9. When the second surface is viewed from above, one of the second functional layers continuously covers the periphery of the openings of the multiple flow channels. The liquid dispensing substrate according to claim 1.
10. When the second surface is viewed from above, one of the first functional layers continuously covers the periphery of the openings of the multiple flow channels. The liquid dispensing substrate according to claim 1.
11. The system further comprises a discharge port forming substrate having a discharge port for discharging the liquid supplied through the aforementioned flow path, At least one end of the second functional layer is positioned so as not to come into contact with the liquid. The liquid dispensing substrate according to claim 1.
12. The system further comprises a discharge port forming substrate having a discharge port for discharging the liquid supplied through the aforementioned flow path, At least one end of the first functional layer is located in a position that does not come into contact with the liquid. The liquid dispensing substrate according to claim 11.
13. One end of the first functional layer and one end of the second functional layer are located between the flow channel forming substrate and the discharge port forming substrate. The liquid dispensing substrate according to claim 11.
14. Multiple discharge ports are arranged on the discharge port forming substrate along the first direction. With the second surface viewed from above, one of the second functional layers covers the periphery of the openings of the plurality of flow channels formed along the first direction. The liquid dispensing substrate according to claim 11.
15. Multiple discharge ports are arranged on the discharge port forming substrate along the first direction. With the second surface viewed from above, one of the second functional layers covers the periphery of the openings of the multiple flow channels formed along a second direction intersecting the first direction. The liquid dispensing substrate according to claim 11.
16. The channel-forming substrate has an energy generating element formed at a position opposite the discharge port, which generates energy for discharging liquid from the discharge port. In the channel-forming substrate, the second functional layer is not formed at a position corresponding to the energy generating element. The liquid dispensing substrate according to claim 13.
17. The energy generating element is a heater. The liquid dispensing substrate according to claim 16.
18. The energy generating element is a piezoelectric element. The liquid dispensing substrate according to claim 16.
19. A liquid discharge substrate according to claim 1, A liquid dispensing head characterized by the following features.
20. A method for manufacturing a liquid dispensing substrate that dispenses liquid, A preparation step of preparing a channel-forming substrate having a first surface, a second surface facing the opposite direction to the direction the first surface faces, and a channel configured to penetrate from the first surface to the second surface and allow liquid to flow through it, A first forming step of forming a first functional layer on the second surface and the inner circumferential surface of the flow channel, A second forming step of forming a second functional layer on the first functional layer formed on the second surface of the channel forming substrate, A first etching step in which etching is performed on the second functional layer, A second etching step in which etching is performed on the first functional layer, including, A method for manufacturing a liquid discharge substrate, characterized by the following:
21. In the first forming step, the first functional layer is formed by the ALD method. In the second formation step, the second functional layer is formed by plasma CVD or sputtering. A method for manufacturing a liquid dispensing substrate according to claim 20.
22. In the first etching step and the second etching step, a common mask is used. A method for manufacturing a liquid dispensing substrate according to claim 20.
23. In the first etching step, dry etching is performed. In the second etching step, wet etching is performed. A method for manufacturing a liquid dispensing substrate according to claim 22.
24. In the first etching step, the first functional layer is used as a stop layer. A method for manufacturing a liquid dispensing substrate according to claim 20.
25. The second surface of the channel-forming substrate includes Ir or Pt, In the first etching step, the second surface is used as a stop layer. A method for manufacturing a liquid discharge substrate according to claim 20.
26. The second surface of the channel-forming substrate includes Ir or Pt, In the second etching step, the second surface is used as a stop layer. A method for manufacturing a liquid discharge substrate according to claim 20.