CN114983032A - MEMS structure atomizing core and preparation method thereof - Google Patents

Abstract

The invention discloses an MEMS structure atomizing core and a preparation method thereof. The MEMS structure atomizing core comprises: the supporting structure is provided with a first surface and a second surface which are arranged back to back, the first surface is provided with an oil storage groove, the second surface is provided with an oil guide hole communicated with the oil storage groove, and the second surface and the first surface are arranged back to back; and the resistance heating structure is arranged on the second surface of the supporting structure, and after the resistance heating structure is connected with a power supply, the fluid medium conveyed from the oil guide hole can be contacted with the resistance heating structure and heated and atomized. The invention not only ensures that the atomizing core has higher reliability and better temperature consistency control, can accurately control the resistance range, but also can accurately control the oil seepage rate and quantity, can realize the manufacturing with batch and low cost by combining the semiconductor process, and avoids the pollution caused by the sintering of the ceramic process.

Description

MEMS structure atomizing core and preparation method thereof

technical field

The invention particularly relates to a MEMS structure atomizing core and a preparation method thereof, belonging to the technical field of atomizers.

Background technique

Atomization technology is the process of turning a fluid medium into small droplets in a certain way. At present, the main methods of atomization are high-pressure gas atomization, ultrasonic atomization, microwave heating atomization, and resistance heating atomization. As the "heart" of atomization technology, the atomization core determines the atomization effect.

The structure of the currently commonly used atomizing core is shown in Figure 1, which is formed on a porous ceramic by a printing process to form a heating resistor. The tiny pores in porous ceramics are the key to the ceramic atomizing core to achieve stable liquid-conducting and liquid-locking functions. Due to surface tension and capillary action, the fluid medium can penetrate into the atomizing core uniformly and be adsorbed on the surface of the atomizing core.

Compared with other atomization methods, the temperature of the porous ceramic atomizing core will rise faster and the temperature uniformity will be better during the heating process. However, since the resistance paste is prepared by the screen printing process, followed by high-temperature sintering and other processes. On the one hand, high-temperature sintering will cause shrinkage of the resistance paste, resulting in the discreteness of the resistance; on the other hand, due to the porous ceramic support structure It is a microporous structure. During the printing process, the resistive paste will penetrate into the pores, causing defects such as disconnection and circuit breakage. However, the atomizing core with the alloy diaphragm as the heating structure will cause a gap between the alloy diaphragm and the porous ceramic due to the difference of the thermal expansion coefficient in its heating working state, which will affect the atomization effect.

SUMMARY OF THE INVENTION

The main purpose of the present invention is to provide a MEMS structure atomizing core and a preparation method thereof, so as to overcome the deficiencies in the prior art.

In order to realize the foregoing invention purpose, the technical scheme adopted in the present invention includes:

An embodiment of the present invention provides a MEMS structure atomizing core, including:

A support structure, the support structure has a first surface and a second surface disposed opposite to each other, the first surface is provided with an oil storage tank, and the second surface is provided with an oil guide hole communicated with the oil storage tank, so the second surface is arranged opposite to the first surface;

A resistance heating structure, the resistance heating structure is arranged on the second surface of the support structure, when the resistance heating structure is connected to the power supply, the fluid medium conveyed from the oil guide hole can contact the resistance heating structure and Atomized by heating.

The embodiment of the present invention also provides the preparation method of the MEMS structure atomizing core, which is characterized by comprising:

A patterned conductive material layer is formed on the second surface of the support structure, and serves as a resistance heating structure;

An oil storage groove is formed on the first surface of the support structure, and an oil guide hole is formed at the bottom of the oil storage groove through the support structure, so that the fluid medium conveyed from the oil guide hole can interact with the conductive material. layer contact.

Compared with the prior art, the advantages of the present invention include: the atomizing core of the MEMS structure atomizing core structure provided by the present invention is more reliable, the temperature consistency is better controlled, and the resistance range can be precisely controlled; and It can also precisely control the rate and quantity of oil seepage. Combined with semiconductor technology, it can achieve mass and low-cost manufacturing and avoid pollution caused by ceramic sintering.

Description of drawings

Fig. 1 is a kind of porous ceramic atomizing core sample in the prior art;

2 is a schematic structural diagram of a MEMS structure atomizing core provided in Embodiment 1 of the present invention;

3 is a schematic structural diagram of a heating resistor provided in a typical embodiment of the present invention;

4 is a schematic diagram of a preparation process of a MEMS structure atomizing core provided in Embodiment 1 of the present invention;

5 is a schematic structural diagram of a preparation process of a MEMS structure atomizing core provided in Embodiment 1 of the present invention;

FIG. 6 is a schematic structural diagram of a MEMS structure atomizing core provided in Embodiment 2 of the present invention.

Detailed ways

In view of the deficiencies in the prior art, the inventor of the present application was able to propose the technical solution of the present invention after long-term research and extensive practice. The technical solution, its implementation process and principle will be further explained as follows.

Develop an atomizing core with simple process, good performance and high precision, which is suitable for electronic cigarettes, humidifiers, face steamers, fog machines, medical atomizers and other application fields.

In order to overcome the shortcomings of the current thick-film printing and porous ceramic atomizing cores prepared from alloy membranes, the present invention proposes to use the deposition technology in the semiconductor process to realize the patterning of the metal thin film on the silicon-based support structure on the silicon-based support structure. , forming a stable heating resistance structure; on the other hand, through dry and wet etching, a high-precision oil storage tank can be formed, and a precise oil-guiding hole can be formed, which can control the penetration rate of the fluid medium during the atomization process. Good atomization effect.

An embodiment of the present invention provides a MEMS structure atomization core. The MEMS structure atomization core uses single crystal silicon as the main substrate and is divided into two main structures. The middle core is a heating structure, and the deposited metal material is used as the heating part. ; The lower layer is a supporting structure, a frame structure formed with monocrystalline silicon as a base material, and an array of micro-holes is prepared in the middle.

An embodiment of the present invention provides a MEMS structure atomizing core, including:

A support structure, the support structure has a first surface and a second surface disposed opposite to each other, the first surface is provided with an oil storage tank, and the second surface is provided with an oil guide hole communicated with the oil storage tank, so the second surface is arranged opposite to the first surface;

A resistance heating structure, the resistance heating structure is arranged on the second surface of the support structure, when the resistance heating structure is connected to the power supply, the fluid medium conveyed from the oil guide hole can contact the resistance heating structure and Atomized by heating.

In some specific embodiments, the support structure includes a first support structure and a second support structure arranged in layers, wherein the thermal conductivity of the first support structure is greater than the thermal conductivity of the second support structure, and the storage The oil groove is arranged at least in the second support structure, the resistance heating structure is arranged on the first support structure, and the oil guide hole passes through the first support structure and the second support structure at the same time.

In some specific implementations, the first support structure is a silicon oxide support structure, the thickness of the first support structure is 100 nm-2000 nm, the second support structure is a monocrystalline silicon support structure, and the first support structure is a monocrystalline silicon support structure. The thickness of the second support structure is 100 μm-5000 μm, and the thickness of the second support structure at the bottom of the oil storage tank is 2-5 times the thickness of the first support structure.

In some more specific embodiments, the first support structure is formed by oxidation of a surface region of the second support structure.

In some specific embodiments, the second surface of the support structure is provided with a plurality of the oil guide holes, and the plurality of the oil guide holes are distributed in an array;

In some specific embodiments, the cross-sectional shape of the oil guide hole includes any one or a combination of two or more of circles, ovals, squares, triangles, and zigzags.

In some specific embodiments, the whole of the plurality of the oil guide holes is distributed in a square, S-shape or a zigzag shape.

In some specific embodiments, the diameter of the oil guiding holes is 1 μm-500 μm, and the gap between adjacent oil guiding holes is 1 μm-500 μm.

In some more specific embodiments, the second surface of the support structure has a first area and a second area, and the resistance heating structure includes a patterned layer of conductive material overlying at least the first area, so The oil guide hole is arranged at least in the second area.

In some specific embodiments, the second area of the second surface of the support structure is further provided with a plurality of guide grooves, each of the guide grooves is also communicated with the oil guide hole, and the The depth of the guide groove is less than 1/2 of the thickness of the first support structure.

In some specific embodiments, each guide groove is also filled with a guide layer, the guide layer is formed by combining metal particles and non-metal particles, wherein the metal particles and the resistance heating structure The material of the non-metallic particles is the same as that of the second support structure, and the resistance heating structure is also directly contacted or connected with the guide layer.

In some more specific embodiments, the thickness of the conductive material layer is 100 nm-500 μm.

In some specific embodiments, the material of the conductive material layer includes any one of Ni, Cr, Au, Pt, Mo, and W, or an alloy formed by two or more.

The embodiment of the present invention also provides the preparation method of the MEMS structure atomizing core, which is characterized by comprising:

A patterned conductive material layer is formed on the second surface of the support structure, and serves as a resistance heating structure;

An oil storage groove is formed on the first surface of the support structure, and an oil guide hole is formed at the bottom of the oil storage groove through the support structure, so that the fluid medium conveyed from the oil guide hole can interact with the conductive material. layer contact.

In some more specific embodiments, the preparation method specifically includes:

oxidizing a part of single crystal silicon near the second surface of the supporting structure to form silicon oxide, and using the oxidized silicon oxide as the first supporting structure, and using the remaining part that is not oxidized as the second supporting structure;

An oil storage tank is formed on the first surface of the support structure, and the entire oil storage tank is arranged in the second support structure, and the oil guide hole is formed at the bottom of the oil storage tank, and making the oil guide hole continuously pass through the second support structure and the first support structure;

A resistive heating structure is formed on the surface of the first support structure.

In some more specific embodiments, the preparation method specifically includes:

First, a plurality of guide grooves are formed on the surface layer of the first support structure, so that the guide grooves are communicated with the oil guide holes, and then a plurality of metal particles and non-metal particles are formed in the guide grooves. The guiding layer, wherein the metal particles are of the same material as the resistance heating structure, and the non-metal particles are of the same material as the second support structure;

The resistance heating structure is formed on the surface of the first support structure, and the resistance heating structure is directly contacted or connected with the guiding layer.

The technical solution, its implementation process and principle will be further explained below in conjunction with the accompanying drawings and specific implementation cases. Unless otherwise specified, the oxidation, deposition, etching and other processes used in the embodiments of the present invention can be It is a method known to those skilled in the art, and its specific process conditions are not limited here.

The MEMS structure atomizing core structure provided by the present invention is mainly divided into two parts, one part is a structure in which a heating film is deposited, and the other part is an oil seepage structure including array-distributed guide holes. This invention not only makes the reliability of the atomizing core higher, the temperature consistency is better controlled, and the resistance range can be precisely controlled; it can also accurately control the rate and quantity of oil leakage. Combined with the semiconductor process, it can achieve batch production and low cost. It can avoid the pollution caused by the sintering of the ceramic process.

Example 1

Please refer to FIG. 2 and FIG. 3 , a MEMS structure atomizing core structure includes a second support structure 200 , a first support structure 100 and a resistance heating structure 300 that are stacked in sequence, and the second support structure 200 has a back-to-back A first surface of a support structure 100, the first support structure 100 has a second surface facing away from the second support structure 200, the first surface of the second support structure 200 is provided with an oil storage tank 210, the The second surface of the second support structure 200 is provided with a plurality of oil guide holes 220, the flow guide holes 220 continuously penetrate the first support structure 100 and the second support structure 200 and communicate with the oil storage tank 210, the resistance The heating structure 200 is disposed on the second surface of the first support structure 100 . When the resistance heating structure 300 is connected to the power supply, the fluid medium conveyed from the oil guide hole 220 can contact the resistance heating structure 300 and make a contact with the resistance heating structure 300 . After being heated and atomized, the fluid medium includes e-liquid and the like.

In this embodiment, the thermal conductivity of the first support structure 100 is greater than that of the second support structure 200 , the entire oil storage tank 210 is disposed in the second support structure 200 , and the oil storage tank 210 has With the variable diameter structure gradually changing in the direction toward the first support structure 100 , the radial or lateral dimension of the oil storage tank 210 is gradually reduced in the direction toward the first support structure 100 .

In this embodiment, the first support structure 100 is a silicon oxide support structure, the thickness of the first support structure 100 is 100 nm-2000 nm, the second support structure 200 is a monocrystalline silicon support structure, and the first support structure 100 is a monocrystalline silicon support structure. The thickness of the second support structure 200 is 100 μm-5000 μm, and the thickness of the second support structure 200 remaining at the bottom of the oil storage tank 210 is 2-5 times the thickness of the first support structure 100 .

In this embodiment, the first support structure 100 is formed by oxidizing the surface area of the second support structure 200 .

In this embodiment, the second surface of the support structure is provided with a plurality of the oil guide holes 220, the plurality of the oil guide holes 220 are distributed in an array, and the cross-sectional shape of the oil guide holes 220 includes a circle, Any one or a combination of two or more of the oval, square, triangle, and rice-shaped shapes, the overall distribution of the plurality of the oil guide holes 220 is square, S-shaped or mouth-shaped, and the diameter of the oil guide holes 220 is 1 μm-500 μm, and the gap between adjacent oil guide holes 220 is 1 μm-500 μm.

In this embodiment, the second surface of the first support structure 100 has a first area and a second area, and the resistance heating structure 300 includes a patterned conductive material layer overlying the first area, so The oil guide holes 220 are arranged in the second area, wherein the conductive material layer is arranged in a pattern, and the pattern structure of the conductive material layer can be as shown in FIG. shape, flat spiral, etc.

In this embodiment, the thickness of the conductive material layer is 100 nm-500 μm, and the material of the conductive material layer includes any one of Ni, Cr, Au, Pt, Mo, and W, or an alloy formed by two or more. .

In this embodiment, the first surface of the first support structure 100 is further provided with a pad 400, the pad 400 is electrically connected to the resistance heating structure 300, and the pad 400 may be a metal pad or the like , parameters such as the size of the pad are not specifically limited and described here.

Please refer to FIG. 4 and FIG. 5 , a method for preparing a MEMS structure atomizing core, including:

1) Using monocrystalline silicon as the raw material for making the support structure, and cleaning the monocrystalline silicon;

2) using an oxidation process to oxidize a part of the monocrystalline silicon surface layer to form silicon oxide, and use the silicon oxide part formed after the oxidation as the first support structure, and use the remaining part of the monocrystalline silicon as the second support structure;

3) forming the shape of the resistance heating structure by photolithography on the surface of the first support structure;

4) depositing a metal material on the surface of the first support structure after photolithography to form a conductive material layer, and using the patterned conductive material layer as a resistance heating structure;

5) An oil storage tank is formed on the surface of the second support structure facing away from the first support structure by means of etching and other methods, and the oil storage tank and the resistance heating structure are arranged opposite to each other, and the remaining amount of the bottom of the oil storage tank is controlled. The thickness of the remaining second support structure is 2-5 times the thickness of the first support structure;

6) A plurality of oil guide holes are formed in the area of the surface of the first support structure that is not covered by the resistance heating structure by means of etching or the like, and the oil guide holes are made to continuously penetrate the first support structure and the first support structure in the thickness direction. a second support structure, communicated with the oil storage tank;

7) Making pads on the surface of the first support structure, and electrically connecting the pads to the resistance heating structure.

Example 2

Please refer to FIG. 6 , the structure of a MEMS structure atomizing core in this embodiment is basically the same as that in Embodiment 1, the difference is that the first support structure 100 in this embodiment faces away from the second support structure 200 . The two surfaces are also provided with a plurality of guide grooves, each guide groove is also communicated with at least one oil guide hole 220 , and the depth of the guide groove is less than 1/1 of the thickness of the first support structure 100 . 2. A guide layer 500 is also filled in each guide groove, and the guide layer 500 is formed by combining metal particles and non-metal particles, wherein the metal particles are of the same material as the resistance heating structure 300, so The non-metallic particles are of the same material as the second support structure 200 , the volume ratio of the metal particles in the guiding layer 500 is 50-75%, and the resistance heating structure 300 is also in direct contact with the guiding layer or Connection, wherein the particle sizes of the metal particles and non-metal particles are both micro and nano-scale, and the metal particles and non-metal particles can be formed by sintering, bonding and lamination, which are not specifically limited here. .

In this embodiment, the good compatibility of the guiding layer itself with the resistance heating structure and the silicon oxide support structure can be used, and from a material point of view, the connection between the resistance heating structure and the silicon oxide support structure can be strengthened. On the other hand, the guiding layer is used as an anchor point, which strengthens the bond between the two from a mechanical point of view, and overcomes the warpage and detachment that may be caused by the difference in thermal expansion coefficient between the resistance heating structure and the silicon oxide support structure. question. In addition, the existence of these guide grooves and guide layers can also form a three-dimensional heating path in the silicon oxide support structure (the resistance heating structure is in surface contact with the silicon oxide support structure, and the surface heating is presented, and these guide layers are deeply oxidized inside the silicon support structure, so it also adds a heating dimension), which further improves the heating efficiency and uniformity of heating.

It should be understood that the above-mentioned embodiments are only intended to illustrate the technical concept and characteristics of the present invention, and the purpose thereof is to enable those who are familiar with the art to understand the content of the present invention and implement it accordingly, and cannot limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention should be included within the protection scope of the present invention.

Claims (10)

1. a MEMS structure atomizing core, is characterized in that comprising: A support structure, the support structure has a first surface and a second surface disposed opposite to each other, the first surface is provided with an oil storage tank, and the second surface is provided with an oil guide hole communicated with the oil storage tank, so the second surface is arranged opposite to the first surface; A resistance heating structure, the resistance heating structure is arranged on the second surface of the support structure, when the resistance heating structure is connected to the power supply, the fluid medium conveyed from the oil guide hole can contact the resistance heating structure and Atomized by heating. 2 . The MEMS structure atomizing core according to claim 1 , wherein the support structure comprises a first support structure and a second support structure arranged in layers, wherein the thermal conductivity of the first support structure is greater than that of the first support structure. 3 . The thermal conductivity of two supporting structures, the oil storage tank is provided at least in the second supporting structure, the resistance heating structure is provided on the first supporting structure, and the oil guiding holes pass through the first supporting structure at the same time structure and a second support structure. 3. The MEMS structure atomization core according to claim 1, wherein the first support structure is a silicon oxide support structure, the thickness of the first support structure is 100nm-2000nm, and the second support structure It is a monocrystalline silicon support structure, and the thickness of the second support structure is 100 μm-5000 μm. 4 . The atomizing core of MEMS structure according to claim 3 , wherein the first support structure is formed by oxidizing the surface area of the second support structure. 5 . 5 . The MEMS structure atomizing core according to claim 3 , wherein: the second surface of the support structure is provided with a plurality of the oil guide holes, and the plurality of the oil guide holes are distributed in an array; 6 . Preferably, the cross-sectional shape of the oil guide hole includes any one or a combination of two or more of circles, ovals, squares, triangles, and rice-shaped shapes; Preferably, the whole of the plurality of the oil guide holes is distributed in a square, S-shape or a zigzag shape; Preferably, the diameter of the oil guiding holes is 1 μm-500 μm, and the gap between adjacent oil guiding holes is 1 μm-500 μm. 6 . The atomizing core of MEMS structure according to claim 2 , wherein the second surface of the support structure has a first area and a second area, and the resistance heating structure includes at least a layer disposed on the first area. 7 . a patterned conductive material layer in a region, the oil-conducting holes are arranged at least in the second region; Preferably, the second area of the second surface of the support structure is further provided with a plurality of guide grooves, each of the guide grooves is also communicated with the oil guide hole, and the depth of the guide groove is less than 1/2 of the thickness of the first support structure; Preferably, each guide groove is also filled with a guide layer, and the guide layer is formed by combining metal particles and non-metal particles, wherein the metal particles are of the same material as the resistance heating structure, and the The non-metallic particles are of the same material as the second support structure, and the resistance heating structure is also directly contacted or connected with the guide layer. 7 . The MEMS structure atomizing core according to claim 6 , wherein: the thickness of the conductive material layer is 100 nm-500 μm; preferably, the material of the conductive material layer comprises Ni, Cr, Au, Pt, Any one of Mo and W is a single substance or an alloy formed of two or more. 8. The preparation method of the MEMS structure atomizing core according to any one of claims 1-7, characterized in that it comprises: A patterned conductive material layer is formed on the second surface of the support structure, and serves as a resistance heating structure; An oil storage groove is formed on the first surface of the support structure, and an oil guide hole is formed at the bottom of the oil storage groove through the support structure, so that the fluid medium conveyed from the oil guide hole can interact with the conductive material. layer contact. 9. preparation method according to claim 8, is characterized in that, specifically comprises: oxidizing a part of the monocrystalline silicon near the second surface of the support structure to form silicon oxide, and using the oxidized silicon oxide as the first support structure, and using the unoxidized remaining part as the second support structure; An oil storage tank is formed on the first surface of the support structure, and the entire oil storage tank is arranged in the second support structure, and the oil guide hole is formed at the bottom of the oil storage tank, and making the oil guide hole continuously pass through the second support structure and the first support structure; A resistive heating structure is formed on the surface of the first support structure. 10. preparation method according to claim 8 or 9, is characterized in that, specifically comprises: First, a plurality of guide grooves are formed on the surface layer of the first support structure, so that the guide grooves are communicated with the oil guide holes, and then metal particles and non-metal particles are formed in the guide grooves. The guiding layer, wherein the metal particles are of the same material as the resistance heating structure, and the non-metal particles are of the same material as the second support structure; The resistance heating structure is formed on the surface of the first support structure, and the resistance heating structure is directly contacted or connected with the guiding layer.

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