MEMS component, vibration cavity structure thereof, and liquid ejection head

Abstract

The invention provides an MEMS component and a vibration cavity structure and a liquid ejection head thereof, the MEMS component comprises a piezoelectric actuator structure, and the vibration cavity structure is in contact with the piezoelectric actuator structure; the vibration cavity structure comprises a vibration cavity and a cavity wall, and the inner side wall of the cavity wall is arc-shaped; the vibration cavity structure is made of silicon and / or silicon oxide. The cavity wall of the vibration cavity structure disclosed by the invention adopts the design of the arc-shaped inner side wall, so that the deformation volume of the vibration cavity is increased on the premise that the density of the spray holes of the liquid spray head is not changed, and the size of liquid drops is effectively increased; and meanwhile, the liquid ejection head can realize ejection of liquid drops with the same size by using relatively small driving voltage, so that the energy consumption is reduced.

Description

Technical Field

[0001] This disclosure relates to the field of MEMS (Micro Electro Mechanical Systems) technology, and in particular to a MEMS component and its vibration cavity structure and liquid ejector. Background Technology

[0002] For microelectromechanical systems (MEMS) piezoelectric liquid ejectors, the droplet size is determined by the deformation volume of the vibrating diaphragm in the piezoelectric actuator structure. The deformation volume of the vibrating diaphragm is directly related to the length and width design of the vibrating cavity; generally, the larger the area of ​​the cavity, the greater the deformation.

[0003] However, for liquid nozzles with high orifice density, this high density limits the width of the vibrating cavity. Simply widening the vibrating cavity within this limited range thins the isolation sidewalls between adjacent cavities, leading to more severe crosstalk during vibration. Extending the cavity length, on the other hand, yields low vibration efficiency and undoubtedly increases the cost of the liquid nozzle. Summary of the Invention

[0004] The purpose of this disclosure is to provide a MEMS component and its vibration cavity structure and liquid ejector head.

[0005] This disclosure solves the above-mentioned technical problems through the following technical solution:

[0006] In a first aspect, a vibration cavity structure for a MEMS component is provided, the MEMS component including a piezoelectric actuator structure, the vibration cavity structure being in contact with the piezoelectric actuator structure;

[0007] The vibration cavity structure includes a vibration cavity body and a cavity wall, wherein the inner wall of the cavity wall is arc-shaped;

[0008] The vibrating cavity structure is made of silicon and / or silicon oxide.

[0009] Optionally, the central width W1 of the vibration cavity is greater than or equal to the port width W2 of the vibration cavity.

[0010] Optionally, the central width W1 satisfies 0um < W1 < 1000um;

[0011] And / or, the average width W3 of the vibration cavity satisfies 0um < W3 < 550um.

[0012] Optionally, the vibration cavity structure is fabricated using a dry etching process;

[0013] And / or, the inner wall of the cavity is covered with a passivation film.

[0014] Secondly, a MEMS component is provided, the MEMS component including a piezoelectric actuator structure and the aforementioned vibration cavity structure.

[0015] Optionally, the MEMS component's <110> The angle θ between the crystal orientation and the long side of the vibration cavity structure satisfies 0°≤θ≤180°;

[0016] The long side of the vibration cavity structure is in the same direction as the long side of the piezoelectric actuator structure.

[0017] Optionally, the MEMS component includes a flow channel through which liquid flows;

[0018] The vibration cavity structure is connected to the flow channel, and the connection part has rounded corners.

[0019] Optionally, the piezoelectric actuator structure includes a vibrating diaphragm layer, a lower electrode layer, a piezoelectric material layer and an upper electrode layer stacked sequentially from bottom to top;

[0020] The vibration cavity structure is in contact with the vibration diaphragm layer.

[0021] Optionally, the vibrating diaphragm layer comprises, from bottom to top, silicon dioxide, silicon, and zirconium dioxide;

[0022] The thickness t1 of the vibrating diaphragm layer satisfies 1um ≤ t1 ≤ 3um;

[0023] The thickness t2 of the silicon dioxide satisfies 0 < t2 ≤ 3 μm, the thickness t3 of the silicon satisfies 0.1 ≤ t3 ≤ 3 μm, and the thickness t4 of the zirconium dioxide satisfies 0 < t4 ≤ 0.3 μm.

[0024] And / or, the lower electrode layer comprises, from bottom to top, platinum and strontium ruthenium oxide;

[0025] The thickness t5 of the lower electrode layer satisfies 50nm≤t5≤300nm;

[0026] The thickness t6 of the platinum in the lower electrode layer satisfies 50nm≤t6≤250nm, and the thickness t7 of the strontium ruthenium in the lower electrode layer satisfies 0nm<t7≤100nm.

[0027] And / or, the upper electrode layer comprises, from bottom to top, strontium ruthenate and platinum;

[0028] The thickness t8 of the upper electrode layer satisfies 15nm≤t8≤100nm;

[0029] The thickness t9 of the strontium ruthenate in the upper electrode layer satisfies 0 < t9 ≤ 100 nm, and the thickness t10 of the platinum in the upper electrode layer satisfies 0 ≤ t10 ≤ 100 nm.

[0030] And / or, the piezoelectric material layer includes lead zirconate titanate;

[0031] The thickness t11 of the lead zirconate titanate satisfies 0.5um≤t11≤3um.

[0032] Thirdly, a liquid ejector head is provided, the liquid ejector head including the MEMS component described above.

[0033] Based on common knowledge in the field, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred embodiments of this disclosure.

[0034] The positive and progressive effects of this disclosure are as follows:

[0035] This disclosure discloses a MEMS component, its vibration cavity structure, and a liquid ejector head. The MEMS component includes a piezoelectric actuator structure, and the vibration cavity structure is in contact with the piezoelectric actuator structure. The vibration cavity structure includes a vibration cavity body and a cavity wall, with the inner sidewall of the cavity wall being arc-shaped. This arc-shaped inner sidewall cavity design increases the deformation volume of the vibration cavity body while maintaining the same nozzle density in the liquid ejector head, thereby effectively increasing the droplet size. Simultaneously, the liquid ejector head can use a smaller driving voltage to achieve the same droplet size, thus saving energy. Attached Figure Description

[0036] Figure 1 This is a first cross-sectional schematic diagram of the vibration cavity structure of the MEMS component provided in Embodiment 1 of this disclosure;

[0037] Figure 2 This is a second cross-sectional schematic diagram of the vibration cavity structure of the MEMS component provided in Embodiment 1 of this disclosure;

[0038] Figure 3 for Figure 2 The corresponding top view;

[0039] Figure 4 A schematic diagram of the fabrication method of the vibration cavity structure of the MEMS component provided in Embodiment 1 of this disclosure;

[0040] Figure 5 This is a third cross-sectional schematic diagram of the vibration cavity structure of the MEMS component provided in Embodiment 1 of this disclosure;

[0041] Figure 6 This is a schematic diagram of the MEMS component structure provided in Embodiment 2 of this disclosure;

[0042] Figure 7for Figure 1 A magnified view of part A in the middle. Detailed Implementation

[0043] The present disclosure is further illustrated below by way of embodiments, but the present disclosure is not limited to the scope of the embodiments described herein.

[0044] The prefixes such as "first" and "second" used in this disclosure are merely for distinguishing different descriptive objects and do not limit the position, order, priority, quantity, or content of the described objects. The use of ordinal numbers and other prefixes used to distinguish descriptive objects in this disclosure does not constitute a limitation on the described objects. The description of the described objects is given in the claims or the context of the embodiments, and should not be construed as an unnecessary limitation. Furthermore, in the description of this embodiment, unless otherwise stated, "multiple" means two or more.

[0045] Example 1

[0046] This embodiment provides a vibration cavity structure for a MEMS component, such as... Figure 1 and Figure 2 As shown, the MEMS component includes a piezoelectric actuator structure 1, and a vibration cavity structure 2 is in contact with the piezoelectric actuator structure 1.

[0047] The vibration cavity structure 2 includes a vibration cavity 21 and a cavity wall 22, the inner wall of the cavity wall 22 being arc-shaped;

[0048] The vibrating cavity structure 2 is made of silicon and / or silicon oxide.

[0049] For example, silicon oxide can be silicon dioxide (SiO2).

[0050] The vibration cavity structure of the MEMS component in this embodiment has an arc-shaped inner wall. This arc-shaped inner wall design increases the deformation volume of the vibration cavity while keeping the nozzle density of the liquid ejector unchanged, thereby effectively increasing the droplet size.

[0051] Figure 2 This is a cross-sectional schematic diagram of a vibrating cavity structure arranged periodically. In an optional embodiment, such as... Figure 2 As shown, the central width W1 of the vibration cavity 21 is greater than the port width W2 of the vibration cavity 21.

[0052] In an optional embodiment, the central width W1 of the vibration cavity 21 satisfies 0um < W1 < 1000um;

[0053] In an optional embodiment, the average width W3 of the vibrating cavity 21 satisfies 0µm < W3 < 550µm.

[0054] In an optional embodiment, the average width W3 of the vibration cavity 21 satisfies 50µm < W3 < 100µm.

[0055] In an alternative embodiment, the vibration cavity structure 2 is fabricated using a dry etching process.

[0056] Traditional methods use wet etching to etch the vibration cavity of the vibration cavity. The advantage of this method is that it is low cost. Dry etching allows for greater freedom in design patterns, so it is possible to create vibration cavity structures with arc-shaped inner walls.

[0057] In an alternative implementation, such as Figure 1 As shown, the inner wall of the cavity wall 22 is covered with a passivation film 23.

[0058] In an alternative embodiment, the material of the passivation film includes, but is not limited to, silicon dioxide (SiO2).

[0059] For example, materials for passivation films can also include titanium dioxide (TiO2), zirconium dioxide (ZrO2), etc.

[0060] Figure 4 This illustration shows a method for fabricating a vibration cavity structure according to the present disclosure, such as... Figure 4 As shown, the fabrication method of the vibrating cavity structure mainly includes:

[0061] 1. SOI (Silicon-On-Insulator) wafer preparation.

[0062] 2. Thin film deposition, from bottom to top: zirconium dioxide (ZrO2), platinum (Pt), strontium ruthenium (SRO), lead zirconate titanate (PZT), strontium ruthenium (SRO) and platinum (Pt).

[0063] 3. Etching of the upper electrode: Pt and SRO are etched to form the upper electrode layer.

[0064] 4. Etching of piezoelectric material: PZT is etched to form a piezoelectric material layer.

[0065] 5. Etching of the lower electrode: Etching SRO, Pt and ZrO2 to form the lower electrode layer.

[0066] 6. Cavity etching to form a vibrating cavity.

[0067] 7. BOX (Buried Oxide) etching, which is the etching of the buried oxide layer in SOI. This step can be omitted in some designs.

[0068] 8. Passivation layer deposition to form a passivation film. The materials for the passivation film include SiO2, TiO2, ZrO2, etc.

[0069] Example 2

[0070] This embodiment provides a MEMS component, such as... Figure 1 As shown, the MEMS component includes a piezoelectric actuator structure 1 and a vibration cavity structure 2 provided in Embodiment 1.

[0071] In an alternative implementation, such as Figure 5 As shown, the MEMS component <110> The angle θ between the crystal orientation and the long side of the vibration cavity structure satisfies 0°≤θ≤180°;

[0072] The long side of the vibrating cavity structure is in the same direction as the long side of the piezoelectric actuator structure.

[0073] Among them, MEMS components <110> The angle between the crystal orientation and the long side of the piezoelectric actuator structure also satisfies 0°-180°.

[0074] The long side of the vibrating cavity structure can be the direction of liquid flow within the vibrating cavity. Figure 3 The image shows the long side direction of the vibrating cavity structure. Figure 6 This is a schematic cross-sectional view of the vibrating cavity structure along its long side.

[0075] MEMS components <110> The crystal orientation forms an angle θ with the long side of the vibration cavity structure, which facilitates the arrangement of MEMS components.

[0076] In an alternative implementation, the MEMS component includes a flow channel through which liquid flows;

[0077] The vibrating cavity structure is connected to the flow channel, and the connection part has rounded corners.

[0078] The rounded corner design avoids stress concentration during vibration, thereby improving the reliability of MEMS components.

[0079] In an alternative implementation, such as Figure 7 As shown, the piezoelectric actuator structure 1 includes a vibrating diaphragm layer 11, a lower electrode layer 12, a piezoelectric material layer 13 and an upper electrode layer 14 stacked sequentially from bottom to top;

[0080] The vibration cavity structure 2 is in contact with the vibration membrane layer 11.

[0081] Specifically, the vibrating diaphragm covers the vibrating cavity 21 and the top of the cavity wall.

[0082] In an alternative implementation, such as Figure 7As shown, the vibrating membrane layer 11 comprises silicon dioxide (SiO2), silicon (Si), and zirconium dioxide (ZrO2) from bottom to top.

[0083] The thickness t1 of the vibrating diaphragm 11 satisfies 1um ≤ t1 ≤ 3um;

[0084] The thickness t2 of silicon dioxide satisfies 0 < t2 ≤ 3 μm, the thickness t3 of silicon satisfies 0.1 ≤ t3 ≤ 3 μm, and the thickness t4 of zirconium dioxide satisfies 0 < t4 ≤ 0.3 μm.

[0085] In an alternative implementation, such as Figure 7 As shown, the lower electrode layer 12 consists of platinum (Pt) and strontium ruthenium (SRO) from bottom to top.

[0086] The thickness t5 of the lower electrode layer 12 satisfies 50nm≤t5≤300nm;

[0087] The thickness t6 of platinum in the lower electrode layer 12 satisfies 50nm≤t6≤250nm, and the thickness t7 of strontium ruthenium in the lower electrode layer 12 satisfies 0nm<t7≤100nm.

[0088] In an alternative implementation, such as Figure 6 As shown, the upper electrode layer 14 consists of strontium ruthenium (SRO) and platinum (Pt) from bottom to top.

[0089] The thickness t8 of the upper electrode layer 14 satisfies 15nm≤t8≤100nm;

[0090] The thickness t9 of strontium ruthenate in the upper electrode layer 14 satisfies 0 < t9 ≤ 100 nm, and the thickness t10 of platinum in the upper electrode layer satisfies 0 ≤ t10 ≤ 100 nm.

[0091] In an alternative implementation, such as Figure 7 As shown, the piezoelectric material layer 13 includes lead zirconate titanate (PZT).

[0092] The thickness t11 of lead zirconate titanate satisfies 0.5um≤t11≤3um.

[0093] The MEMS component in this embodiment includes a piezoelectric actuator structure and the vibration cavity structure from Embodiment 1. The vibration cavity structure is in contact with the piezoelectric actuator structure. The vibration cavity structure includes a vibration cavity body and a cavity wall, with the inner sidewall of the cavity wall being arc-shaped. This arc-shaped inner sidewall design increases the deformation volume of the vibration cavity body while maintaining the same nozzle density of the liquid ejector head, thereby effectively increasing the droplet size.

[0094] Example 3

[0095] This embodiment protects a liquid ejector head, which includes the MEMS component provided in Embodiment 2.

[0096] The liquid ejector head is used in conjunction with piezoelectric inkjet printing technology for inkjet printing. The liquid ejector head may also include other components, such as nozzles.

[0097] The liquid ejector head of this embodiment includes the MEMS component from Embodiment 2. The MEMS component includes a piezoelectric actuator structure and a vibration cavity structure from Embodiment 1. The vibration cavity structure is in contact with the piezoelectric actuator structure. The vibration cavity structure includes a vibration cavity body and a cavity wall, with the inner sidewall of the cavity wall being arc-shaped. This arc-shaped inner sidewall cavity design increases the deformation volume of the vibration cavity body while maintaining the same nozzle density, thereby effectively increasing the droplet size. Simultaneously, the liquid ejector head can use a smaller driving voltage to achieve the same droplet size, thus saving energy.

[0098] While specific embodiments of this disclosure have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of this disclosure is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of this disclosure, but all such changes and modifications fall within the scope of protection of this disclosure.

Claims

1. A vibrating cavity structure of a MEMS component, characterized by, The MEMS component comprises a piezoelectric actuator structure, and the vibration cavity structure is in contact with the piezoelectric actuator structure. The vibration cavity structure comprises a vibration cavity and a cavity wall, and an inner side wall of the cavity wall is arc-shaped. The vibration cavity structure is made of silicon and / or silicon oxide.

2. The vibrating cavity structure of claim 1, wherein A central width W1 of the vibration cavity is greater than or equal to a port width W2 of the vibration cavity.

3. A vibrating cavity structure according to claim 2, characterized in that The central width W1 satisfies 0um < W1 < 1000um. And / or, an average width W3 of the vibration cavity satisfies 0um < W3 < 550um.

4. The vibrating cavity structure of claim 1, wherein, The vibration cavity structure is made by a dry etching process. And / or, the inner side wall of the cavity wall is covered with a passivation film.

5. A MEMS component, characterized by, The MEMS component comprises a piezoelectric actuator structure, and the vibration cavity structure is in contact with the piezoelectric actuator structure.

6. The MEMS component of claim 5, wherein, An angle θ between a <110> crystal direction of the MEMS component and a long side direction of the vibration cavity structure satisfies 0° ≤ θ ≤ 180°. The long side direction of the vibration cavity structure is the same as that of the piezoelectric actuator structure.

7. The MEMS component of claim 5, wherein, The MEMS component comprises a flow channel for liquid to flow through. The vibration cavity structure is connected to the flow channel, and a connection part is a rounded corner.

8. The MEMS component of claim 5, wherein, The piezoelectric actuator structure comprises, from bottom to top, a vibrating diaphragm layer, a lower electrode layer, a piezoelectric material layer, and an upper electrode layer. The vibrating diaphragm layer is in contact with the vibration cavity structure.

9. The MEMS component of claim 8, wherein, The vibrating diaphragm layer comprises, from bottom to top, silicon dioxide, silicon, and zirconium dioxide. A thickness t1 of the vibrating diaphragm layer satisfies 1um ≤ t1 ≤ 3um. A thickness t2 of the silicon dioxide satisfies 0 < t2 ≤ 3um, a thickness t3 of the silicon satisfies 0.1 ≤ t3 ≤ 3um, and a thickness t4 of the zirconium dioxide satisfies 0 < t4 ≤ 0.3um. And / or, the lower electrode layer comprises, from bottom to top, platinum and strontium ruthenate. A thickness t5 of the lower electrode layer satisfies 50nm ≤ t5 ≤ 300nm. A thickness t6 of the platinum in the lower electrode layer satisfies 50nm ≤ t6 ≤ 250nm, and a thickness t7 of the strontium ruthenate in the lower electrode layer satisfies 0nm < t7 ≤ 100nm. And / or, the upper electrode layer comprises, from bottom to top, strontium ruthenate and platinum. A thickness t8 of the upper electrode layer satisfies 15nm ≤ t8 ≤ 100nm. A thickness t9 of the strontium ruthenate in the upper electrode layer satisfies 0 < t9 ≤ 100nm, and a thickness t10 of the platinum in the upper electrode layer satisfies 0 ≤ t10 ≤ 100nm. And / or, the piezoelectric material layer comprises lead zirconate titanate. A thickness t11 of the lead zirconate titanate satisfies 0.5um ≤ t11 ≤ 3um.

10. A liquid ejection head, characterized by, The liquid ejection head comprises the MEMS component according to any one of claims 5-9.

Images