MESH TYPE ATOMIZER USING POROUS THIN FILM AND METHOD FOR MANUFACTURING THE SAME

Abstract

A mesh type atomizer according to an embodiment includes a porous thin film having a multi-hole structure, a metal layer covering a remaining area except a nozzle area in which droplets are sprayed through the holes on a surface of the porous thin film, and an ultrasonic transducer to output ultrasonic waves to vibrate the porous thin film. According to an embodiment, it is possible to atomize a liquid into nanometer-level fine particles using the porous thin film including nanometer sized holes. It is possible to precisely adjust the sprayed droplet size by setting the shape, size and cycle of the nozzle in the manufacturing process, and it is possible to selectively increase the strength of the mesh by growing the metal material in the hole of the porous thin film through electroplating.

Claims

1. A mesh type atomizer using a porous thin film, comprising: a porous thin film having a multi-hole structure; a metal layer covering a remaining area except a nozzle area in which droplets are sprayed through the holes on a surface of the porous thin film; and an ultrasonic transducer to output ultrasonic waves to vibrate the porous thin film.

2. The mesh type atomizer using a porous thin film according to claim 1, wherein the hole in the remaining area except the nozzle area is, at least in part, filled with a metal material.

3. The mesh type atomizer using a porous thin film according to claim 1, wherein the hole of the porous thin film is a few nanometers to a few micrometers in diameter.

4. The mesh type atomizer using a porous thin film according to claim 3, wherein the porous thin film is anodic aluminum oxide.

5. The mesh type atomizer using a porous thin film according to claim 1, wherein the nozzle area includes at least one hole, and the droplet sprayed through the nozzle area is a few nanometers to a few micrometers in diameter.

6. The mesh type atomizer using a porous thin film according to claim 5, wherein a distance between the nozzle area and an adjacent nozzle area is set to prevent the droplets sprayed in each nozzle area from merging.

7. A method for manufacturing a mesh type atomizer using a porous thin film, comprising: providing a porous thin film having a multi-hole structure; forming a photosensitive layer in a nozzle area in which droplets are to be sprayed through the holes on a surface of the porous thin film; depositing a metal layer on the porous thin film and the photosensitive layer; removing the photosensitive layer from the porous thin film; and combining an ultrasonic transducer with the porous thin film.

8. The method for manufacturing a mesh type atomizer using a porous thin film according to claim 7, further comprising: after depositing the metal layer on the porous thin film and the photosensitive layer, connecting an electroplating metal material to the metal layer, and growing a metal material in the hole of a remaining area except the nozzle area through electroplating.

9. The method for manufacturing a mesh type atomizer using a porous thin film according to claim 7, wherein the hole of the porous thin film is a few nanometers to a few micrometers in diameter.

10. The method for manufacturing a mesh type atomizer using a porous thin film according to claim 9, wherein the porous thin film is anodic aluminum oxide.

11. The method for manufacturing a mesh type atomizer using a porous thin film according to claim 7, wherein the nozzle area includes at least one hole, and the droplet sprayed through the nozzle area is a few nanometers to a few micrometers in diameter.

12. The method for manufacturing a mesh type atomizer using a porous thin film according to claim 11, wherein a distance between the nozzle area and an adjacent nozzle area is set to prevent the droplets sprayed in each nozzle area from merging.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The following is a brief introduction to necessary drawings in the description of the embodiments to describe the technical solutions of the embodiments of the present disclosure or the existing technology more clearly. It should be understood that the accompanying drawings are for the purpose of describing the embodiments of the present disclosure and are not intended to be limiting of the present disclosure. Additionally, for clarity of description, illustration of some elements in the accompanying drawings may be exaggerated and omitted.

[0023] FIG. 1 shows the structure of a mesh type atomizer according to an embodiment.

[0024] FIG. 2 is a cross-sectional view of a mesh structure used in a mesh type atomizer according to an embodiment.

[0025] FIG. 3 shows a porous thin film used to manufacture a mesh structure according to an embodiment.

[0026] FIGS. 4A to 4E are diagrams for describing a method for manufacturing a mesh type atomizer according to an embodiment.

[0027] FIGS. 5A and 5B are diagrams for describing a method for manufacturing a mesh structure with increased strength according to an embodiment.

[0028] FIGS. 6A and 6B are cross-sectional views of a mesh structure with increased strength according to an embodiment.

[0029] FIG. 7 shows a photographic image of a mesh type atomizer manufactured according to an embodiment and a scanning electron microscope (SEM) image of a nozzle area made of a porous thin film.

DETAILED DESCRIPTION

[0030] The following detailed description of the present disclosure is made with reference to the accompanying drawings, in which particular embodiments for practicing the present disclosure are shown for illustration purposes. These embodiments are described in sufficiently detail for those skilled in the art to practice the present disclosure. It should be understood that various embodiments of the present disclosure are different but do not need to be mutually exclusive. For example, particular shapes, structures and features described herein in connection with one embodiment may be embodied in other embodiment without departing from the spirit and scope of the present disclosure. It should be further understood that changes may be made to the positions or placement of individual elements in each disclosed embodiment without departing from the spirit and scope of the present disclosure. Accordingly, the following detailed description is not intended to be taken in limiting senses, and the scope of the present disclosure, if appropriately described, is only defined by the appended claims along with the full scope of equivalents to which such claims are entitled. In the drawings, similar reference signs denote same or similar functions in many aspects.

[0031] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings, but the scope of protection is not restricted or limited by the embodiments.

[0032] FIG. 1 shows the structure of a mesh type atomizer according to an embodiment. Referring to FIG. 1, the atomizer 1 according to an embodiment includes a mesh structure 10 for breaking up a liquid into fine particles and an ultrasonic transducer 20 for vibrating the mesh structure 10 using ultrasonic waves. The mesh structure 10 may be divided into at least one nozzle area A where droplets are sprayed and a remaining area B covered with a metal layer. Although not shown for simplification of description, the mesh type atomizer may further include essential or optional elements for its operation.

[0033] FIG. 2 is a cross-sectional view of the mesh structure used in the mesh type atomizer according to an embodiment. Referring to FIG. 2, the mesh structure includes a porous thin film 110 having a multi-hole structure and a metal layer 120 that covers the remaining area B except the nozzle area A where droplets are sprayed through the holes on the surface of the porous thin film 110. The hole in the remaining area B except the nozzle area A may be, at least in part, filled with a metal material 130.

[0034] FIG. 3 shows the porous thin film used to manufacture the mesh structure according to an embodiment. According to the embodiment, the porous thin film 110 includes a plurality of holes having very small diameters of a few nanometers to a few micrometers. For example, anodic aluminum oxide having nanometer sized holes may be used. The type of the porous thin film or the size of the hole is not limited thereto and various types of porous thin films having holes of various sizes may be used.

[0035] Referring to FIG. 2, the metal layer 120 covers the remaining area B except the nozzle area A where droplets are sprayed through the holes on the surface of the porous thin film 110. Since the remaining area B is blocked by the metal layer 120, a liquid is only sprayed through the nozzle area A. The nozzle area A includes at least one hole, and the droplet sprayed through the nozzle area A has a very small size on the level of a few nanometers to a few micrometers. The droplet size may vary depending on the number of holes in the nozzle area A and the diameter of each hole. The size of a droplet passing through a hole is about twice larger than the diameter of the hole, and may become larger when the droplet and droplets of adjacent holes merge, so the actually sprayed droplet size is not equal to the hole size, but the sprayed droplet size may be adjusted by adjusting the size of the nozzle area in the mesh manufacturing process. For example, nanometer sized droplets may be formed by using the porous thin film (AAO) including nanometer-level holes and limiting the size of the nozzle.

[0036] According to an embodiment, the holes in the area B other than the nozzle may be partially filled with the metal material 130 to increase the strength of the mesh or selectively adjust the ultrasonic resonant frequency. The metal material in the hole may be grown using electroplating.

[0037] Referring back to FIG. 1, the distance between a nozzle area and its adjacent nozzle area is indicated in T, and the diameter of the nozzle area is indicated in d.sub.nozzle. The distance T between the nozzle areas may be set to an optimal distance to prevent droplets sprayed in each nozzle area from merging. The diameter d.sub.nozzle of the nozzle area may be set, taking the sprayed droplet size into account. That is, the diameter may be set to a larger value to make droplets larger, or may be set to a smaller value to make droplets smaller.

[0038] The ultrasonic transducer 20 outputs ultrasonic waves to vibrate the mesh structure 10. As shown in FIG. 1, the ring type ultrasonic transducer 20 attached to the edge of the mesh structure 10 may be used. The mesh structure 10 vibrates by the ultrasonic waves outputted from the ultrasonic transducer 20, and atomizes a liquid into fine particles (preferably, droplets having nanometer diameters).

[0039] Hereinafter, a method for manufacturing a mesh type atomizer according to an embodiment will be described with reference to FIGS. 4A to 4E.

[0040] According to an embodiment, first, a porous thin film 110 having a multi-hole structure is provided as shown in FIG. 4A. The porous thin film 110 includes a plurality of holes, and the diameter d.sub.pore of each hole may be a few nanometers to a few micrometers. For example, anodic aluminum oxide having nanometer-sized holes may be used as the porous thin film 110.

[0041] Subsequently, a photosensitive layer 111 is formed on a part of the surface of the porous thin film 110 as shown in FIG. 4B. An area having the photosensitive layer is a nozzle area where droplets will be sprayed through the holes.

[0042] Subsequently, a metal layer 120 is deposited, covering the porous thin film 110 and the photosensitive layer 111 as shown in FIG. 4C. There is no limitation as to the type of the metal material of which the metal layer 120 is made, and the metal layer 120 may be deposited using the existing thin film deposition process, for example, chemical vapor deposition (CVD) and physical vapor deposition (PVD).

[0043] Subsequently, the photosensitive layer 111 is removed from the porous thin film 110 to form a mesh structure. In the mesh structure, as shown in FIG. 4D, the area A in which the photosensitive layer 111 has been formed is exposed and the remaining area B is covered with the metal layer 120. The area A is the nozzle area where droplets are sprayed through the holes.

[0044] The mesh structure 10 is formed through the process of FIGS. 4A to 4D, and an ultrasonic transducer 20 is combined with the mesh structure 10 to manufacture an atomizer according to an embodiment as shown in FIG. 4E. As shown in FIG. 4E, the ring type ultrasonic transducer 20 may be used.

[0045] FIGS. 5A and 5B are diagrams for describing a method for manufacturing a mesh structure with increased strength according to an embodiment.

[0046] In this embodiment, the process of FIGS. 4A to 4C is performed in the same way as the previous embodiment. After the step of depositing the metal layer 120 on the porous thin film 110 and the photosensitive layer 111 in FIG. 4C, the metal layer 120 and an electroplating metal material 121 are connected through an electrode as shown in FIG. 5A. The type of the electroplating metal material 121 may vary depending on the type of metal of which the metal layer 120 is made.

[0047] When the metal layer 120 and the electroplating metal material 121 are connected with the electrode, a metal material 130 is grown in the hole through oxidation and reduction of metal ions in an electrolyte as shown in FIG. 5B. In this instance, the metal material is not grown in the area having the photosensitive layer 111 (later formed as the nozzle area), and the metal material in the hole is only grown in the remaining area. Accordingly, it is possible to increase the strength of the mesh structure while not inhibiting the liquid atomization function of the porous thin film.

[0048] FIGS. 6A and 6B are cross-sectional views of the mesh structure with increased strength according to an embodiment. As described above, the metal material 130 may be grown in the hole of the porous thin film 110 through electroplating, and the height t.sub.metal of the metal material 130 may be adjusted by adjusting the electroplating process time. FIG. 6A shows that the hole is partially filled with the metal material 130, and FIG. 6B shows that the hole is fully filled with the metal material 130. The strength of the mesh structure may be adjusted by selectively adjusting the thickness of the metal material, thereby selectively adjusting the ultrasonic resonant frequency.

[0049] FIG. 7 shows a photographic image of the mesh type atomizer manufactured according to an embodiment and a scanning electron microscope (SEM) image of the nozzle area having the porous thin film structure. In FIG. 7, (A) shows the whole structure of the mesh type atomizer 1. (B) is an enlarged photographic image of the mesh structure 10 of the atomizer, and (C) is an enlarged photographic image of one of the nozzle areas A included in the mesh structure. As can be seen in (C), one nozzle area includes a plurality of nanometer sized holes through which fine droplets having the size of a few nanometers are sprayed. As shown, the area other than the nozzle area is covered with the metal layer and droplets are not sprayed there.

[0050] According to the mesh type atomizer described hereinabove, it is possible to atomize a liquid into nanometer-level fine particles using the porous thin film including the nanometer sized holes. It is possible to precisely adjust the sprayed droplet size by setting the shape, size and interval of the nozzle in the manufacturing process, and it is possible to selectively increase the strength of the mesh by growing the metal material in the hole of the porous thin film through electroplating. It is possible to form much smaller droplets compared to the existing mesh drilled by laser drilling, and it can be used in various technical fields including medical nebulizers used to administer fine drug particles, fuel injection systems of automotive engines, filters or the like.

[0051] While the present disclosure has been hereinabove described with reference to the embodiments, those skilled in the art will understand that various modifications and changes may be made thereto without departing from the spirit and scope of the present disclosure defined in the appended claims.