Liquid discharge head and liquid discharge device

Abstract

The present invention provides a liquid discharge head and a liquid discharge device. The liquid discharge head includes: an insulating member disposed on a substrate; a resistance heating element disposed in the insulating member and configured to generate heat energy for discharging liquid; a bubble chamber disposed above the insulating member and configured to generate bubbles of liquid based on heat energy; and a temperature sensing element capable of detecting the temperature in the bubble chamber, wherein the temperature sensing element is disposed between the resistance heating element and the bubble chamber, and is located in the conductive layer closest to the bubble chamber among a plurality of conductive layers disposed relative to the insulating member.

Description

[0001] This application is a divisional application of the invention patent application entitled "Liquid Discharge Head and Liquid Discharge Device", filed on May 25, 2021, with application number 202110568828.7. Technical Field

[0002] This invention mainly relates to liquid discharge heads. Background Technology

[0003] Liquid discharge heads in liquid discharge devices, such as inkjet printers, can utilize structures such as electrothermal conversion type or piezoelectric type. Electrothermal conversion type liquid discharge heads include multiple liquid discharge nozzles and corresponding multiple resistance heating elements (also called electrothermal transducers, etc.), and utilize the heat energy generated by driving each resistance heating element to discharge liquid from the corresponding nozzle. This electrothermal conversion type structure can simultaneously reduce the size of the resistance heating elements and improve heating efficiency, thus facilitating an increase in the density of resistance heating elements.

[0004] In some liquid discharge devices, a temperature detection element (temperature sensor) is installed on the liquid discharge head, and the drive control of the resistance heating element is based on the detection result of the temperature detection element (Japanese Patent Application Laid-Open No. 2019-72999 and No. 2009-196265).

[0005] It can be said that when the detection accuracy of the temperature sensing element is improved, the driving control of the resistance heating element can be performed with higher accuracy based on the detection results of the temperature sensing element. In this regard, there is room for structural improvement in the structures described in Japanese Patent Application Publication No. 2019-72999 and No. 2009-196265. Summary of the Invention

[0006] An exemplary objective of this invention is to provide a technique that helps improve the detection accuracy of temperature sensing elements.

[0007] One aspect of the present invention provides a liquid discharge head, comprising: an insulating member disposed on a substrate; a resistance heating element disposed in the insulating member and configured to generate heat energy for discharging liquid; a bubble chamber disposed above the insulating member and configured to generate bubbles of liquid based on the heat energy; and a temperature sensing element capable of detecting the temperature in the bubble chamber, wherein the temperature sensing element is disposed between the resistance heating element and the bubble chamber, and is located in the conductive layer closest to the bubble chamber among a plurality of conductive layers disposed relative to the insulating member.

[0008] Other features of the invention will become clear from the following description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0009] Figure 1A This is a schematic plan view of the liquid discharge head;

[0010] Figure 1B This is a schematic cross-sectional view of the liquid discharge head;

[0011] Figure 1C This is a schematic cross-sectional view of the liquid discharge head;

[0012] Figure 2A This is a schematic plan view of the liquid discharge head;

[0013] Figure 2B This is a schematic cross-sectional view of the liquid discharge head;

[0014] Figure 3A This is a schematic plan view of the liquid discharge head;

[0015] Figure 3B This is a schematic cross-sectional view of the liquid discharge head;

[0016] Figure 4A This is a schematic plan view of the liquid discharge head;

[0017] Figure 4B This is a schematic cross-sectional view of the liquid discharge head;

[0018] Figure 5A This is a schematic plan view of the liquid discharge head;

[0019] Figure 5B This is a schematic cross-sectional view of the liquid discharge head;

[0020] Figure 6A This is a schematic diagram showing the liquid state in the bubble chamber;

[0021] Figure 6B This is a schematic diagram illustrating the liquid state within the bubble chamber; and

[0022] Figure 7 This is a graph showing the temperature changes detected by the temperature sensing element. Detailed Implementation

[0023] The embodiments will be described in detail below with reference to the accompanying drawings. Note that the following embodiments are not intended to limit the scope of the invention. Several features are described in the embodiments, but the invention is not limited to requiring all of these features, and multiple features may be appropriately combined. Furthermore, in the drawings, identical or similar constructions are labeled with the same reference numerals, and repeated descriptions thereof are omitted.

[0024] <First Embodiment>

[0025] Figure 1A This is a schematic plan view of the head substrate 11 included in the liquid discharge head 1 according to the first embodiment. Figure 1B It is along Figure 1A A schematic cross-sectional view taken by cutting line d1-d1 in the figure. Figure 1C It is along Figure 1A A schematic cross-sectional view taken along cutting line d2-d2. The liquid discharge head 1 is installed in a liquid discharge device, such as an inkjet printer, and is capable of applying liquid, such as ink droplets, to a predetermined target.

[0026] Note that, for ease of explanation... Figure 1B and 1C The upper side (the side in the direction of liquid discharge) is defined as the upper side of the liquid discharge head 1 and the head substrate 11, and the opposite side is defined as the lower side.

[0027] The head substrate 11 can be manufactured using known semiconductor manufacturing processes and is formed by, for example, placing multiple elements on a substrate 100 made of semiconductor (e.g., single-crystal silicon). First, an insulating layer 101 is disposed on the substrate 100.

[0028] For example, an inorganic material such as silicon dioxide is used for the insulating layer 101. The insulating layer 101 electrically insulates the plurality of resistance heating elements 102 (described later) and one or more elements (e.g., MOS transistors) or circuit portions configured to drive the respective resistance heating elements 102 from each other. Typically, the insulating layer 101 is formed of multiple layers, and multiple conductive or semiconductor layers forming the respective elements may be arranged between, above, and / or below these layers. The insulating layer 101 may be referred to as an insulating member.

[0029] Within the insulating layer 101, a resistance heating element 102, a connecting member 103, and a wiring member 104 are arranged. The resistance heating element 102 is an electrothermal transducer driven by electricity and generates heat. The connecting member 103 is also referred to as a contact plug, a circuit, etc. The wiring member 104 is also referred to as a wire pattern (or simply a pattern), etc.

[0030] The resistance heating element 102 is connected to the wiring component 104 via the connecting member 103. The resistance heating element 102 can be made of, for example, a metal with high resistance (e.g., silicon nitride tantalum, tungsten nitride, or silicon).

[0031] Components 103 and 104 are made of metals with low resistance. Typically, materials such as tungsten and copper can be used for connecting component 103, and materials such as aluminum and copper can be used for wiring component 104.

[0032] A temperature sensing element 105 is disposed on an insulating layer 101 and above the resistance heating element 102. Furthermore, a connecting member 106 and a wiring member 107 are disposed within the insulating layer 101. The temperature sensing element 105 is used for driving control of the resistance heating element 102 based on the detection result, and is capable of detecting the temperature in the bubble chamber 112, as described in detail below. That is, the detection result of the temperature sensing element 105 is acquired by a control unit (also called a drive control unit or printing control unit, not shown), and the control unit performs driving control of the resistance heating element 102 based on the detection result.

[0033] Temperature sensing element 105 overlaps with resistance heating element 102 in the plan view and is positioned to the outer edge of the resistance heating element 102. Connecting member 106 is also referred to as a contact plug, a passage, etc. Wiring member 107 is also referred to as a wire pattern (or simply a pattern), etc.

[0034] Temperature sensing element 105 is connected to wiring component 107 via connecting member 106. Temperature sensing element 105 can be made of, for example, a metal with a large temperature coefficient of resistance (e.g., iridium, tantalum, titanium, tungsten, silicon, silicon nitride tantalum, or silicon nitride tungsten) or an alloy thereof. Temperature sensing element 105 can be formed as a single layer or by stacking multiple layers. Furthermore, temperature sensing element 105 is preferably made of a material that can be used as an anti-cavitation film.

[0035] Components 106 and 107 are made of metals with low resistance, similar to components 103 and 104. Typically, materials such as tungsten and copper can be used for connecting component 106, and materials such as aluminum and copper can be used for wiring component 107.

[0036] The upper surface of the insulating layer 101 is preferably planarized. The planarization process can usually be performed by CMP (chemical mechanical polishing). Note that the planarization process is performed after the formation of the connecting member 106 and before the formation of the temperature sensing element 105, but it can be performed between the various processes used to form the aforementioned elements 102 to 107.

[0037] In this embodiment, connecting members 103 and 106 are formed separately using independent manufacturing processes. Therefore, the multiple connecting members 103 connecting the resistance heating element 102 and the wiring member 104 are integrally formed, and the multiple connecting members 106 connecting the temperature sensing element 105 and the wiring member 107 are integrally formed.

[0038] In this embodiment, the thickness of the metal film forming the resistance heating element 102 is approximately 10 to 50 nm. The thickness of the metal film forming the wiring member 104 is approximately 500 to 1000 nm. Furthermore, the thickness of the insulating layer 101 between the temperature sensing element 105 and the resistance heating element 102 (i.e., the distance between the upper surface of the metal film forming the resistance heating element 102 and the lower surface of the metal film forming the temperature sensing element 105) is approximately 50 to 200 nm.

[0039] According to this embodiment, the distance between the resistance heating element 102 and the temperature sensing element 105 can be reduced more easily, and this distance can be reduced compared to a structure where the temperature sensing element is arranged below the resistance heating element. Furthermore, according to this embodiment, the temperature sensing element 105 also functions as an anti-cavitation film, thereby improving the quality of the liquid discharge head 1 and reducing manufacturing costs.

[0040] A liquid supply port 108 is provided on the lower surface side of the substrate 100. Furthermore, a nozzle forming member 110 and a film 109 made of photosensitive resin or the like are provided on the upper surface side of the substrate 100. The nozzle forming member 110 forms an orifice (nozzle) 111 and a bubble chamber 112.

[0041] As described in detail below, the bubble chamber 112 is a space or area that facilitates the discharge of liquid by causing the liquid flowing from the supply port 108 to foam, and is formed in the plan view to the outer side extending to the outer edge of the resistance heating element 102. In the figure, the bubble chamber 112 is separated by the nozzle forming member 110 and the filter 109.

[0042] With the above configuration, the liquid discharge head 1 uses the thermal energy of the resistance heating element 102 to discharge liquid from the bubble chamber 112 through the orifice 111. If a portion of the discharged liquid returns from the orifice 111 to the bubble chamber 112 (so-called tailing), liquid is newly supplied to the bubble chamber 112 from the supply port 108, and the bubble chamber 112 is filled with liquid. The temperature detected by the temperature sensing element 105 corresponds to the ratio of liquid returning from the orifice 111 to the newly supplied liquid from the supply port 108. Therefore, the liquid discharge pattern (whether the discharge is proceeding normally) can be determined based on the detection result of the temperature sensing element 105.

[0043] For example, the detection results of the temperature sensing element 105 when the liquid is properly discharged from the orifice 111 and when the liquid is not properly discharged from the orifice 111 will be referred to below. Figure 6A , 6B And 7 are described.

[0044] Figure 6A This is a schematic diagram illustrating a situation where liquid is not properly discharged from orifice 111. Figure 6BThis is a schematic diagram showing the proper discharge of liquid from orifice 111.

[0045] The time elapsed from the start of heating of the resistance heating element 102 is defined as time t. When t = t1, in Figure 6A and Figure 6B In both cases shown, bubbles are generated on the temperature sensing element 105 by heating through the resistance heating element 102. The bubbles contact or cover the upper surface of the temperature sensing element 105.

[0046] At the point t = t2, Figure 6A In this case, the bubble remains on the temperature sensing element 105. On the other hand, in Figure 6B In this case, a portion of the liquid returning from orifice 111 to bubble chamber 112 separates and contacts the upper surface of temperature sensing element 105.

[0047] Figure 7 It shows in Figure 6A and 6B Under the above conditions, the detection results of the temperature sensing element 105, and the change pattern of the temperature (hereinafter referred to as the detection temperature) mainly detected by the temperature sensing element 105. Figure 7 In the diagram, the horizontal axis represents time t, and the vertical axis represents the detected temperature.

[0048] from Figure 7 It is clear that in Figure 6A In the case of t=t2, after t=t2, the detected temperature decreases with a relatively gentle change due to the bubble contacting the upper surface of the temperature detection element 105. On the other hand, in Figure 6B In the case where t = t2, after t = t2, the detected temperature (compared to) is affected by the absorption of some of the heat from the upper part of the temperature sensing element 105 by the liquid. Figure 6A Compared to the situation in the past, the decline was more dramatic.

[0049] According to this embodiment, from Figure 1B and 1C As can be clearly seen, the temperature sensing element 105 is arranged between the resistance heating element 102 and the bubble chamber 112, and positioned close to the liquid in the bubble chamber 112. The temperature sensing element 105 is preferably arranged using a semiconductor manufacturing process in the uppermost layer (the conductive layer closest to the bubble chamber 112) of a plurality of conductive layers formed on the insulating layer 101. Furthermore, from... Figure 1A As can be seen in the plan view, the temperature sensing element 105 is located in the bubble chamber 112. Based on this structure, the temperature sensing element 105 can acquire detection results with high sensitivity.

[0050] Note that in this embodiment, modifications can be made without departing from its scope. For example, the temperature sensing element 105 only needs to be on the uppermost layer directly below the bubble chamber 112, and the insulating layer 101 can further include another upper layer at a location separate from the bubble chamber 112. In other words, the temperature sensing element 105 only needs to be arranged in the conductive layer closest to the bubble chamber 112, and only needs to be on the uppermost layer in the area overlapping with the bubble chamber 112 in the plan view.

[0051] As described above, according to this embodiment, the detection accuracy of the temperature sensing element 105 can be improved, and appropriate drive control of the resistance heating element 102 can be performed based on the detection results of the temperature sensing element 105 with a relatively simple construction. This allows for drive control of the resistance heating element 102 with higher accuracy, for example, based on changes in the detected temperature.

[0052] <Second Embodiment>

[0053] The temperature sensing element 105 is connected to, for example, a constant current source, and a constant current (a current of a predetermined value) can be supplied to the temperature sensing element 105. Therefore, the potential difference generated in the temperature sensing element 105 is acquired as a detection result, and the control unit (not shown) performs drive control of the resistance heating element 102 based on the detection result. In the first embodiment described above (see...), Figure 1A In the diagram, the temperature sensing element 105 (the metal film forming the temperature sensing element 105) is shown as a rectangle. However, the temperature sensing element 105 can be formed in another shape to improve the detection accuracy.

[0054] Figure 2A This is a schematic plan view of the head substrate 12 included in the liquid discharge head 1 according to the second embodiment. Figure 2B It is along Figure 2A A schematic cross-sectional view taken along cutting line d3-d3. In this embodiment, the temperature sensing element (for distinction, temperature sensing element 205) is arranged in a curved shape above the resistance heating element 102, which results in a higher resistance value for the temperature sensing element 205. Therefore, when a constant current is applied to the temperature sensing element 205, the potential difference generated in the temperature sensing element 205 increases, and the detection accuracy of the temperature sensing element 205 improves.

[0055] As another embodiment, the temperature sensing element 205 can be narrowed and arranged linearly. The temperature sensing element 205 can be arranged in a plane along the energizing direction of the resistance heating element 102, passing through the central portion of the resistance heating element 102 where the temperature tends to be higher, or it can be arranged in a direction orthogonal to the energizing direction.

[0056] As described above, according to this embodiment, the same effect as in the first embodiment can be obtained, and the detection accuracy of the temperature detection element 205 can be improved by increasing the resistance value of the temperature detection element 205.

[0057] <Third Embodiment>

[0058] In the first embodiment described above, the temperature sensing element 105 is also used as an anti-cavitation film. However, the temperature sensing function and the anti-cavitation film function can be provided separately. That is, the temperature sensing element 105 (the metal film forming the temperature sensing element 105) and the anti-cavitation film can be provided independently of each other.

[0059] Figure 3A This is a schematic plan view of the head substrate 13 included in the liquid discharge head 1 according to the third embodiment. Figure 3B It is along Figure 3A A schematic cross-sectional view taken along cutting line d4-d4. In this embodiment, the temperature sensing element (temperature sensing element 305 for distinction) and the anti-cavitation film 313 are arranged independently of each other.

[0060] As described above, the heat energy from the resistance heating element 102 generates bubbles in the liquid. An anti-cavitation film protects the resistance heating element 102 from cavitation, which can occur due to the impact of repeated bubble generation and disappearance, as well as electrochemical corrosion of the liquid. Typically, the durability of the anti-cavitation film against cavitation decreases with increasing temperature.

[0061] Therefore, the anti-cavitation film 313 is preferably arranged directly above the area in the resistance heating element 102 where the temperature is prone to rise. In a plan view, the anti-cavitation film 313 is preferably arranged to overlap at least about 5 μm inward from the outer edge of the resistance heating element 102, which corresponds to the effective functional portion of the resistance heating element where the temperature rises.

[0062] from Figure 3A and 3B As can be clearly seen, in this embodiment, the anti-cavitation film 313 is arranged directly above the central portion of the resistance heating element 102 and extends in the plan view to the outside of the outer edge of the resistance heating element 102.

[0063] The temperature sensing element 305 and the anti-cavitation film 313 are electrically isolated from each other. The anti-cavitation film 313 can float, or a predetermined voltage can be applied to it. Furthermore, as... Figure 3B As shown, the resistance heating element 102 and the temperature sensing element 305 are preferably configured such that the distance between them (the distance in the horizontal direction of the substrate 100) Da is small, for example, the distance Da becomes less than 2 μm. For this purpose, the temperature sensing element 305 and the anti-cavitation film 313 are preferably formed such that the distance between them becomes the minimum value allowed in the semiconductor manufacturing process.

[0064] As described above, according to this embodiment, when the temperature sensing element 305 and the anti-cavitation film 313 are disposed separately, the same effect as in the first embodiment can be obtained. Moreover, according to this embodiment, since the temperature sensing element 305 and the anti-cavitation film 313 are disposed close to each other, the cavitation resistance durability of the temperature sensing element 305 can be improved, while the detection accuracy of the temperature sensing element 305 is appropriately maintained.

[0065] Note that in this embodiment, the temperature sensing element 305 and the anti-cavitation film 313 are formed in one step using a known semiconductor manufacturing process, so they can be arranged together in the same layer and made of the same material.

[0066] <Fourth Embodiment>

[0067] In the third embodiment described above, the temperature sensing element 305 is arranged on one side of the anti-cavitation film 313. However, the temperature sensing element 305 may also be arranged on the other side of the anti-cavitation film 313.

[0068] Figure 4A This is a schematic plan view of the head substrate 14 included in the liquid discharge head 1 according to the fourth embodiment. Figure 4B It is along Figure 4A A schematic cross-sectional view taken along cutting line d5-d5. In this embodiment, temperature sensing element 305 is arranged on one side of the anti-cavitation film 313, and another temperature sensing element (temperature sensing element 415 for distinction) is also arranged on the other side. That is, a pair of temperature sensing elements 305 and 415 are arranged on both sides of the anti-cavitation film 313.

[0069] According to this embodiment, since the detection results of two temperature detection elements 305 and 415 can be obtained, the detection accuracy can be further improved compared with the third embodiment.

[0070] Temperature sensing element 415 is connected to wiring component 417 via connecting member 416. Detection results are acquired independently of the detection results of temperature sensing element 305, and signal processing for the detection results can be performed independently. Therefore, deviations in the liquid discharge direction (positional deviations of liquid adhering to the target) can be detected, for example, based on the sensitivity difference between temperature sensing elements 305 and 415.

[0071] Note that in this embodiment, two temperature sensing elements 305 and 415 are arranged for a single resistance heating element 102. However, the number of temperature sensing elements can be three or more.

[0072] Furthermore, a configuration capable of independently acquiring the detection results of temperature sensing elements 305 and 415 has been described. However, temperature sensing elements 305 and 415 can be connected in series. In the latter case, the detection accuracy can be improved because the resistance value of the temperature sensing elements becomes higher.

[0073] <Fifth Embodiment>

[0074] In the third and fourth embodiments described above, the temperature sensing element 305 and the anti-cavitation film are disposed close to each other, which improves the cavitation resistance durability of the temperature sensing element 305 while appropriately maintaining the detection accuracy of the temperature sensing element 305. To further improve the detection accuracy, the structure of the temperature sensing element 305 can be modified.

[0075] Figure 5A This is a schematic plan view of the head substrate 15 included in the liquid discharge head 1 according to the fifth embodiment. Figure 5B It is along Figure 5A A schematic cross-sectional view taken along cutting line d6-d6. In this embodiment, as in the third and fourth embodiments, the temperature sensing element (temperature sensing element 505 for distinction) and the anti-cavitation film (anti-cavitation film 513 for distinction) are provided independently, and the temperature sensing element 505 is configured to include a line pattern.

[0076] In this embodiment, the line pattern forming the temperature sensing element 505 is arranged along the outer periphery of the outer edge of the resistance heating element 102 in a plan view, outside the outer edge. According to this embodiment, the resistance value of the temperature sensing element 505 is higher than in the third and fourth embodiments, thereby further increasing the detection accuracy of the temperature sensing element 505. At this time, as described above (see the third embodiment), the resistance heating element 102 and the temperature sensing element 505 are preferably arranged such that the distance Da between them is small.

[0077] Furthermore, the anti-cavitation film 513 and the temperature sensing element 505 can be locally (preferably at a single point) electrically connected to each other. In this case, the heat from the anti-cavitation film 513 can be transferred to the temperature sensing element 505 without significantly affecting the current flowing to the temperature sensing element 505, and the detection accuracy of the temperature sensing element 505 can be further increased.

[0078] Furthermore, the anti-cavitation film 513 and the temperature sensing element 505 can be made of different materials. This can respectively increase the durability of the anti-cavitation film 513 against cavitation and improve the detection accuracy of the temperature sensing element 505. For example, iridium, tantalum, etc. are preferably used for the anti-cavitation film 513 and silicon nitride tantalum, silicon nitride tungsten, etc. are preferably used for the temperature sensing element 505.

[0079] like Figure 5B As shown, the temperature sensing element 505 and the anti-cavitation film 513 are formed in the same layer. Furthermore, at least the temperature sensing element 505 is positioned close to the liquid in the bubble chamber 112. Therefore, detection results can be obtained with high sensitivity. Therefore, the temperature sensing element 505 is preferably arranged in the uppermost layer of a plurality of conductive layers disposed relative to the insulating layer 101.

[0080] Note that the anti-cavitation film 513 and the temperature sensing element 505 can also be applied to the third and fourth embodiments using different materials.

[0081] As described above, according to this embodiment, the same effect as in the first embodiment can be obtained, and the cavitation resistance of the temperature sensing element 505 and the anti-cavitation film 513 can be further improved, while the detection accuracy of the temperature sensing element 505 can be further improved.

[0082] <Other Embodiments>

[0083] The liquid discharge head 1 shown in the embodiment is disposed in a liquid discharge device, such as an inkjet printer. The inkjet printer may be a single-function printer with only printing capabilities, or a multi-function printer with multiple functions such as printing, faxing, and scanning. Optionally, the inkjet printer may be a manufacturing device used to manufacture, for example, color filters, electronic devices, optical devices, microstructures, etc., by a predetermined printing method.

[0084] Furthermore, "printing" should be understood in a broader sense. Therefore, "printing" can take any form, regardless of whether the object to be formed on the printing medium is important information (such as characters or graphic patterns), and regardless of whether the object is already visible and perceptible to humans.

[0085] The liquid application target of liquid discharge head 1 can also be called the printing medium. "Printing medium" should be understood in a broader sense, just like "printing". Therefore, the concept of "printing medium" can include not only commonly used paper, but also any component that can receive ink, including fabrics, plastic films, metal plates, glass, ceramics, resins, wood and leather materials.

[0086] A typical example of a liquid is ink. Note that the concept of "liquid" can include not only the liquid that forms an image, design, pattern, etc. when applied to a printing medium, but also any additional liquid that can be provided to treat the printing medium or to treat the ink (e.g., to cause the pigments in the ink to solidify or become insoluble).

[0087] Although the invention has been described with reference to exemplary embodiments, it should be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims should be given the broadest interpretation to cover all such modifications and equivalent structures and functions.

Claims

1. A liquid discharge head, comprising: Multiple orifices, each configured to discharge liquid; Insulating components are arranged on a substrate; A resistance heating element is arranged in an insulating component and configured to generate heat energy for discharging liquid; A bubble chamber, which is positioned above an insulating component, is configured to generate liquid bubbles based on thermal energy; as well as A temperature sensing element, disposed relative to at least the aforementioned resistance heating element, is capable of detecting the temperature within the bubble chamber. in, The temperature sensing element is formed of a single layer or multiple layers and is connected to the wiring assembly via at least two connecting members to detect the potential difference of the temperature sensing element. In a vertical section relative to the substrate, the temperature sensing element is arranged between the resistance heating element and the bubble chamber, located in the conductive layer closest to the bubble chamber among multiple conductive layers disposed relative to the insulating member. In the surface viewed along a direction perpendicular to the substrate, the temperature sensing element is at least partially arranged in the bubble chamber. The temperature sensing element and the anti-cavitation film are formed in the same layer, and the anti-cavitation film and the temperature sensing element are locally electrically connected to each other.

2. The liquid discharge head according to claim 1, wherein Temperature sensing elements detect temperature based on the temperature coefficient of resistance.

3. The liquid discharge head according to claim 1, wherein Temperature sensing elements determine the state of the discharged liquid.

4. The liquid discharge head according to claim 1, wherein The temperature sensing element and the anti-cavitation film are made of the same material.

5. The liquid discharge head according to claim 1, wherein The temperature sensing element and the anti-cavitation film are electrically connected to each other at one point.

6. The liquid discharge head according to claim 1, wherein, In the surface viewed along a direction perpendicular to the substrate, the temperature sensing element is arranged outside the resistance heating element.

7. The liquid discharge head according to claim 6, wherein, In the surface viewed along a direction perpendicular to the substrate, the temperature sensing element is arranged such that the distance from the resistance heating element is equal to or less than 2 μm.

8. The liquid discharge head according to claim 1, wherein, Multiple temperature sensing elements are arranged correspondingly to resistance heating elements.

9. The liquid discharge head according to any one of claims 1 to 3, wherein, In the surface viewed along a direction perpendicular to the substrate, the temperature sensing element is at least partially arranged inside the resistance heating element.

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