CAPACITOR AND METHOD FOR MANUFACTURING THE SAME

A capacitor may include a structure body including a first surface and a second surface positioned in opposite directions, where a plurality of openings are positioned on the first surface, a first internal electrode disposed on a region where the plurality of openings are positioned, a dielectric layer disposed on a partial region of the first internal electrode, a second internal electrode disposed on the dielectric layer, a first external electrode disposed on the first surface, and connected to the first internal electrode, and a second external electrode disposed on the first surface, and connected to the second internal electrode.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean Patent Application No. 10-2023-0108463 filed in the Korean Intellectual Property Office on Aug. 18, 2023, the entire contents of which is incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a capacitor and a method for manufacturing the same.

BACKGROUND

Electronic components used in electronic devices include capacitors, inductors, piezoelectric elements, varistors, or thermistors. A multilayer capacitor among such ceramic electronic devices may be used in various electronic devices due to the merit of small size, high capacity, and easy mounting. For example, a multilayer capacitor may be used in a condenser in the form of a chip that is mounted on a substrate of various electronic products such as an image device such as a liquid crystal display device (LCD), a plasma display device panel (PDP), an organic light emitting diode (OLED), or the like, a computer, a personal portable terminal, and a smart phone, and serves to charge or discharge electricity.

With the recent trend toward miniaturization and thinning of electronic products, demand for capacitors with higher capacity than existing multilayer capacitors is increasing.

SUMMARY

The present disclosure attempts to provide a capacitor having a high capacity and a method for manufacturing the same.

However, the objective of the present disclosure is not limited to the aforementioned one, and may be extended in various ways within the spirit and scope of the present disclosure.

A capacitor may include a structure body including a first surface and a second surface positioned in opposite directions, where a plurality of openings are positioned on the first surface, a first internal electrode disposed on a region where the plurality of openings are positioned, a dielectric layer disposed on a partial region of the first internal electrode, a second internal electrode disposed on the dielectric layer, a first external electrode disposed on the first surface, and connected to the first internal electrode, and a second external electrode disposed on the first surface, and connected to the second internal electrode.

The structure body may include anodizing aluminum oxide.

The plurality of openings may include a first opening and a second opening, and the first external electrode may face a region where the first opening is positioned in a direction in which the first surface and the second surface are spaced apart.

The plurality of openings may include a first opening and a second opening, and the first external electrode may be connected to the first internal electrode of a region positioned adjacent to the first opening.

The first external electrode may be connected to the first internal electrode by directly contacting.

The first external electrode may include a first sub-electrode portion contacting the first internal electrode, and a first main electrode portion positioned on the first sub-electrode portion.

The plurality of openings may include a first opening and a second opening, and the second external electrode may face a region where the second opening is positioned, in a direction in which the first surface and the second surface are spaced apart.

The plurality of openings may include a first opening and a second opening, and the second external electrode may be connected to the second internal electrode of a region positioned adjacent to the second opening.

The second external electrode may be connected to the second internal electrode by directly contacting.

The second external electrode may include a second sub-electrode portion contacting the second internal electrode, and a second main electrode portion positioned on the second sub-electrode portion.

The first external electrode and the second external electrode may be provided in a plural quantity, respectively.

The dielectric layer may include one of Al2O3, ZrO2, and HfO2or a combination thereof, or ZAZ which is a ZrO2—Al2O3—ZrO2composite layer.

The first external electrode may cover one or more of the plurality of openings in which the second internal electrode is not disposed, and the second external electrode may cover one or more of the plurality of openings in which the second internal electrode is disposed.

A capacitor may include a structure body of anodizing aluminum oxide, including first surface and a second surface positioned in opposite directions, where a plurality of openings are positioned on the first surface, a first internal electrode disposed on the first surface in a region between the plurality of openings, and on the plurality of openings, a dielectric layer disposed on a partial region of the first internal electrode, a second internal electrode disposed on the dielectric layer, a first external electrode connected to the first internal electrode, and disposed in a direction to which the first surface of the structure body faces, and a second external electrode connected to the second internal electrode, and disposed in the direction to which the first surface of the structure body faces.

The opening may include first openings and a second opening, the dielectric layer and the second internal electrode may not exist in a region where the first openings are adjacent to each other, and the first external electrode may be connected to the first internal electrode of a region positioned adjacent to the first openings.

A filling portion may be disposed on the first internal electrode disposed in a first opening of the plurality of openings.

A method for manufacturing a capacitor may include forming a plurality of openings in a substrate, forming a first internal electrode on a region where the plurality of openings are positioned, forming a dielectric layer in a region where a second opening among the openings is positioned, excluding a region where a first opening among the openings is positioned, and forming a second internal electrode on the dielectric layer.

The method for manufacturing a capacitor may further include forming an insulation material layer on the first internal electrode of a region where the first opening is positioned, and the second internal electrode of a region where the second opening is positioned, and forming an open hole in at least a portion among the region where the first opening is positioned and the region where the second opening is positioned.

A seed layer may be formed on the open hole.

An external electrode layer may be formed on the seed layer.

According to at least one of embodiments, a capacitor having a high capacity and a method for manufacturing the same may be provided.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The present disclosure will be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the disclosure are shown. In order to clearly describe the present disclosure, parts or portions that are irrelevant to the description are omitted, and identical or similar constituent elements throughout the specification are denoted by the same reference numerals. In addition, some constituent elements are exaggerated, omitted, or briefly illustrated in the added drawings, and sizes of the respective constituent elements do not reflect the actual sizes.

Further, the accompanying drawings are provided for helping to easily understand exemplary embodiments disclosed in the present specification, and the technical spirit disclosed in the present specification is not limited by the accompanying drawings, and it will be appreciated that the present disclosure includes all of the modifications, equivalent matters, and substitutes included in the spirit and the technical scope of the present disclosure.

Terms including ordinal numbers such as first, second, and the like will be used only to describe various components, and are not interpreted as limiting these components. The terms are only used to differentiate one component from others.

It will be further understood that terms “comprise” and “have” used in the present specification specify the presence of stated features, numerals, steps, operations, components, parts, or combinations thereof, but do not preclude the presence or addition of one or more other features, numerals, steps, operations, components, parts, or combinations thereof. In addition, unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising” will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.

Further, throughout the specification, the phrase “in a plan view” or “on a plane” means viewing a target portion from the top, and the phrase “in a cross-sectional view” or “on a cross-section” means viewing a cross-section formed by vertically cutting a target portion from the side.

In addition, throughout the specification, “connected” means that two or more components are not only directly connected, but two or more components may be connected indirectly through other components, physically connected as well as being electrically connected, or it may be referred to by different names depending on the location or function, but may mean integral.

Throughout the specification, a substrate S may have a structure that is wide in a plan view and thin in a cross-sectional view, ‘the planar direction of the substrate S’ may indicate a direction parallel to the wide and flat surface of the substrate S, and the ‘thickness direction of the substrate S’ may indicate a direction that is perpendicular to a wide and flat surface of the substrate S.

FIG.1is a drawing showing a capacitor according to an embodiment.

Referring toFIG.1, a capacitor10according to an embodiment includes a structure body100, a first internal electrode210, a dielectric layer220, a second internal electrode230, a first external electrode300and a second external electrode310.

The structure body100includes a first surface100aand a second surface100bpositioned in opposite directions.FIG.1illustrates that the first surface100ais disposed above, and the second surface100bis disposed below. Accordingly, the first surface100amay be referred to as an upper surface, and the second surface100bmay be referred to as a lower surface. In addition, a direction in which the first surface100aand the second surface100bface each other may be referred to as a vertical direction. The structure body100is provided as an insulation material. A plurality of openings110are positioned on the first surface100aof the structure body100. The opening110may be a column-shaped space extending from the first surface100atoward the second surface100b. As an example, the structure body100may be made of porous anodizing aluminum oxide (AAO), and the opening110may be formed by micropores formed in the anodizing aluminum oxide. The aspect ratio of the micropores may be 2000 to 3000. Additionally, the structure body100may have a structure in which the lower portion of the micropore is blocked.

The first internal electrode210is disposed on the opening110. In addition, the first internal electrode210is disposed in a section between adjacent openings110on the first surface100aof the structure body100. Accordingly, in the first internal electrode210, regions positioned on the openings110may be connected to each other by regions positioned on the first surface100aof the structure body100.

The opening110includes a first opening110aand a second opening110b. At least one of the plurality of openings110is provided as the first opening110a, and remaining openings110are provided as the second opening110b.

A filling portion215may be disposed on the first internal electrode210disposed in the first opening110a. The filling portion215may be made of an insulation material. The filling portion215may be formed to fill the space remaining after the first internal electrode210is filled in the first opening110a.

The dielectric layer220is disposed on a partial region of the first internal electrode210. The dielectric layer220is disposed on the first internal electrode210of the second opening110b. In addition, the dielectric layer220is disposed on the first internal electrode210between adjacent second openings110b. The dielectric layer220is not formed on the first opening110a, and is not formed on the first internal electrode210disposed in a region between adjacent first openings110aon the first surface100a.

The second internal electrode230is disposed on the dielectric layer220. That is, the second internal electrode230is disposed on the dielectric layer220of the second opening110b. In addition, the second internal electrode230is disposed on the dielectric layer220between the adjacent second openings110b. Accordingly, the second internal electrode230faces the first internal electrode210interposing the dielectric layer220, in the second openings110band regions between the adjacent second openings110b. The second internal electrode230may be formed to fill an inner space of the second opening110b. The second internal electrode230is not formed in the first opening110aand a region between the adjacent first openings110ain the first surface100a.

The first external electrode300is connected to the first internal electrode210. The first external electrode300is disposed on the first surface100adirection of the structure body100. The first external electrode300may face a region where the first opening110ais positioned in the vertical direction.

The first external electrode300is connected to the first internal electrode210of a region positioned adjacent to the first opening110a. Specifically, in the region positioned adjacent to the first opening110a, the dielectric layer220does not exist on the first internal electrode210. Accordingly, the first external electrode300is provided to directly contact the first internal electrode210of the region positioned adjacent to the first opening110a, and may be connected to the first internal electrode210.

The first external electrode300may include a first sub-electrode portion301and a first main electrode portion302.

The first sub-electrode portion301is connected to the first internal electrode210. At least a portion of the first sub-electrode portion301may be positioned on the first internal electrode210of the region positioned adjacent to the first opening110a. At least a portion of the first sub-electrode portion301may directly contact the first internal electrode210of the region positioned adjacent to the first opening110a.

The first main electrode portion302is connected to the first sub-electrode portion301. At least a portion of the first main electrode portion302may be positioned on the first sub-electrode portion301. At least a portion of the first main electrode portion302may directly contact the first sub-electrode portion301. For example, the first main electrode portion302may directly contact the first sub-electrode portion301, in a direction facing the structure body100.

The second external electrode310is connected to the second internal electrode230. The second external electrode310is disposed on the first surface100adirection of the structure body100. The second external electrode310may face at least a portion of a region where the second opening110bis positioned in the vertical direction.

The second external electrode310may be provided to contact at least a portion of the second internal electrode230of a region positioned adjacent to the second opening110b, and may be connected to the second internal electrode230.

The second external electrode310may include a second sub-electrode portion311and a second main electrode portion312.

The second sub-electrode portion311is connected to the second internal electrode230. At least a portion of the second sub-electrode portion311may be positioned on at least a portion of the second internal electrode230of the region positioned adjacent to the second opening110b. At least a portion of the second sub-electrode portion311may directly contact at least a portion of the second internal electrode230of the region positioned adjacent to the second opening110b. The second sub-electrode portion311may be provided as the same material as the first sub-electrode portion301.

The second main electrode portion312is connected to the second sub-electrode portion311. At least a portion of the second main electrode portion312may be positioned on the second sub-electrode portion311. At least a portion of the second main electrode portion312may directly contact the second sub-electrode portion311. For example, the second main electrode portion312may directly contact the second sub-electrode portion311, in a direction facing the structure body100. The second main electrode portion312may be provided as the same material as the first main electrode portion302.

In the first internal electrode210disposed adjacent to the first opening110a, an insulating portion250may be positioned on a region other than a region contacting the first external electrode300. The insulating portion250may be positioned to fill a region where a portion in the first external electrode300disposed apart from the first internal electrode210and the first internal electrode210face each other. In addition, the insulating portion250may be positioned to fill a region where a portion in the first external electrode300disposed apart from the first internal electrode210and the second external electrode310face each other.

In addition, in the second internal electrode230disposed adjacent to the second opening110b, the insulating portion250may be positioned on a region other than a region contacting the second external electrode310. The insulating portion250may be positioned to fill a region where a portion in the second external electrode310disposed apart from the second internal electrode230and the second internal electrode230face each other.

In addition, the insulating portion250may be positioned to fill a step positioned outside a region where the opening110is formed in the structure body100. In the structure body100, the insulating portion250may be positioned to surround at least a portion of outer periphery of the region where the opening110is formed.

The insulating portion250may be the same material as the filling portion215.

FIG.2toFIG.14are drawings showing a manufacturing method of a capacitor according to an embodiment.

Hereinafter, a manufacturing method of the capacitor10according to an embodiment will be described with reference toFIG.2toFIG.14.

Referring toFIG.2, the substrate S forming the structure body100is provided. The substrate S is provided with the plurality of openings110formed therein. The substrate S may be made of anodic aluminum oxide (AAO), and the openings110may be micropores formed by an anodic oxidation method. At this time, the lower end portion of the opening110is provided in a blocked state. The substrate S may be in a state where a region where the opening110is positioned is divided into a size corresponding to the size of the capacitor10through etching using a mask. The mask may be made by using photoresist PR or the like. Accordingly, in the substrate S, a step may be formed outside the region where the opening110is positioned. Additionally, the substrate S may be provided while being positioned on the process substrate PS. The process substrate PS improves the operability of the substrate S during the manufacturing process of the capacitor10and prevents damage to the substrate S. The process substrate PS may be a silicon wafer.

Referring toFIG.3, in the structure body100, the first internal electrode210is formed on the region where the opening110is positioned. The first internal electrode210is formed on the opening110. In addition, the first internal electrode210is formed on a region where the openings110are adjacent to each other. Accordingly, the first internal electrodes210are formed to be connected to each other. The opening110is formed by an anodic oxidation method to have a diameter of several tens of nanometers, and the first internal electrode210may be formed by an atomic layer deposition (ALD). The first internal electrode210may be formed of TiN or the like. The first internal electrode210may be formed in a thickness of 2.9 nm to 3.1 nm.

Referring toFIG.4, in the structure body100, an anti-deposition mask M1is formed on the region where the first opening110ais positioned. The anti-deposition mask M1may be formed through the photoresist PR.

Referring toFIG.5, in the structure body100, the dielectric layer220is formed on the region where the second opening110bis positioned. That is, the dielectric layer220is formed on the first internal electrode210of the second opening110b. In addition, the dielectric layer220is formed on the first internal electrode210of a region where the second openings110bare adjacent to each other. The dielectric layer220may be formed by an atomic layer deposition (ALD). The dielectric layer220may be formed one of metal oxides such as Al2O3, ZrO2, and HfO2. In addition, the dielectric layer220may be formed as a combination of metal oxides such as Al2O3, ZrO2, and HfO2. In addition, the dielectric layer220may be formed as a ZAZ, which is a ZrO2—Al2O3—ZrO2composite layer. At this time, the ZrO2, Al2O3, ZrO2layers may have thicknesses of 1.9 nm to 2.1 nm, 0.29 nm to 0.31 nm, 1.9 nm to 2.1 nm, respectively.

On the first internal electrode210of the region where the first opening110ais positioned, formation of the dielectric layer220is prevented by the anti-deposition mask M1.

Referring toFIG.6, in the structure body100, the second internal electrode230is formed on the region where the second opening110bis positioned. That is, the second internal electrode230is formed on the dielectric layer220of the second opening110b. In addition, the second internal electrode230is formed on the dielectric layer220of the region where the second openings110bare adjacent to each other. Accordingly, the second internal electrodes230are formed to be connected to each other. The second internal electrode230may be formed of TiN or the like. The second internal electrode230is formed to fill an interior of the second opening110b, and thereby voids may be prevented from generating in the interior of the second opening110b. At this time, the second internal electrode230may be formed by an atomic layer deposition (ALD). In addition, as for the second internal electrode230, after performing the atomic layer deposition, an additional process for filling the interior of the second opening110bmay be performed. An additional process for filling the interior of the second opening110bmay be performed by using a conductive material, such that the second internal electrode230may be formed together with the region on which the atomic layer deposition is performed.

On the first internal electrode210of the region where the first opening110ais positioned, formation of the second internal electrode230is prevented by the anti-deposition mask M1.

Referring toFIG.7, after the anti-deposition mask M1is removed, an insulation material layer IM is formed. A lift-off process, a polishing process, and the like may be used for removal of the anti-deposition mask M1.

The insulation material layer IM is formed to cover the region where the opening110is positioned. That is, the insulation material layer IM is formed to cover the first internal electrode210on the region where the first opening110ais positioned, such that the first internal electrode210is not externally exposed. In addition, the insulation material layer IM is formed to cover the second internal electrode230on the region where the second opening110bis positioned, such that the second external electrode310is not externally exposed. In addition, an interior of the first opening110ais filled with an insulation material, so as to remove a void in the interior of the first opening110a. Accordingly, the insulation material filled in the interior of the first opening110amay form the filling portion215. In addition, the insulation material layer IM may be formed to fill a step formed outside the region where the opening110is positioned. The insulating material may be polyimide (PI) or the like.

Referring toFIG.8, an open hole OP is formed in the insulation material layer IM1. The open hole OP is formed in at least a portion of the region where the first opening110ais positioned and the region where the second opening110bis positioned, respectively. Through the open hole OP formed in the region where the first opening110ais positioned, the first internal electrode210formed in the region where the first opening110ais positioned is externally exposed. Through the open hole OP formed in the region where the second opening110bis positioned, the second internal electrode230formed in the region where the second opening110bis positioned is externally exposed. The open hole OP may be formed by a lithography process.

Referring toFIG.9, a seed layer SL is formed on the open hole OP. The seed layer SL is formed of a metal material such as Ti, Cu, or the like. The seed layer SL may be formed through a sputtering process. The seed layer SL formed on the open hole OP of the region where the first opening110ais positioned may contact the first internal electrode210. The seed layer SL formed on the open hole OP of the region where the second opening110bis positioned may contact the second internal electrode230.

Referring toFIG.10, an external electrode mask M2is formed on the insulation material layer IM1. The external electrode mask M2is formed on an outer periphery of an upper end portion of the open hole OP. A pattern by the external electrode mask M2is formed such that the seed layer SL formed on the open hole OP may be externally exposed. The external electrode mask M2may be formed through the photoresist PR.

Referring toFIG.11, an external electrode layer E is formed on the seed layer SL. The external electrode layer E is formed on the seed layer SL formed in the open hole OP by the pattern by the external electrode mask M2. The external electrode layer E may be formed through a plating process using Cu, Sn, Ag, or the like.

Referring toFIG.12, the external electrode mask M2is removed. A lift-off process, an ashing process, or the like may be used for removal of the external electrode mask M2.

Referring toFIG.13, the seed layer SL positioned on the insulation material layer IM1is removed. In the process described above inFIG.9, the seed layer SL may be formed on the insulation material layer IM1positioned outside the open hole OP. Accordingly, when the external electrode mask M2is formed, the seed layer SL may be positioned between the external electrode layer E and the insulation material layer IM1. After the external electrode layer E is formed, the seed layer SL is externally exposed if the external electrode mask M2is removed. Therefore, by removing the externally exposed seed layer SL, the external electrode layers E are electrically separated from each other. Accordingly, the external electrode layer E becomes the first main electrode portion302and a second main electrode portion312, respectively. In addition, the seed layer SL positioned below the first main electrode portion302and the second main electrode portion312become the first sub-electrode portion301and a second sub-electrode portion311, respectively.

An etching process or the like may be used for removal of the externally exposed seed layer SL.

Referring toFIG.14, a dicing process is performed, to separate each capacitor10from each other. Also, prior to the dicing process, the process substrate PS may be separated. In addition, prior to the dicing process, a reflow process to change the shape of the external electrodes300and310may be performed.

FIG.15is a drawing schematically showing a planar shape of a capacitor according to an embodiment.

Referring toFIG.15, in the capacitor10, the first external electrode300and the second external electrode310may be disposed in a direction facing the first surface100aof the structure body100. The first external electrode300is disposed, in a body, to face the region where the first opening110ais positioned, and connected to the first internal electrode210. The second external electrode310is disposed to face at least a portion of the region where the second opening110bis positioned, and connected to the second internal electrode230. In addition, the first internal electrodes210are entirely connected to each other, and the second internal electrodes230are entirely connected to each other.

Most of the first internal electrode210and the second internal electrode230are disposed on the opening110. Although only a portion of the openings110are shown inFIG.15for convenience, a large number of the openings110are located in a nanostructure in the structure body100made of anodizing aluminum oxide (AAO). Accordingly, based on a plane crossing a direction in which the first surface100aand the second surface100bof the structure body100face each other, a surface area of the first internal electrode210and the second internal electrode230is significantly larger than area occupied by the structure body100. As a result, the capacitor10may have a very large capacity compared to its size.

FIG.16is a drawing schematically showing a planar shape of a capacitor according to another embodiment.

Referring toFIG.16, in a capacitor10a, the first external electrode300and the second external electrode310may be disposed in the direction facing the first surface100aof the structure body100.

Based on a plane crossing a direction in which the first surface100aand the second surface100bof the structure body100face each other, when the opening110is positioned, an area occupied by the first external electrode300and the second external electrode310may be small in comparison to an area. Accordingly, the capacitor10amay include a plurality of first external electrodes300. In addition, the capacitor10amay include a plurality of second external electrodes310.

The structure body100may include a plurality of regions where the first opening110ais positioned. In the structure body100, each of the first external electrodes300is disposed to face the region where the first opening110ais positioned, and connected to the first internal electrode210. In addition, in the structure body100, each of the second external electrodes310is disposed to face a portion of the region where the second opening110bis positioned, and connected to the second internal electrode230. The first internal electrodes210disposed across the plurality of openings110are connected to each other. Accordingly, in the structure body100, a position of the first opening110awhere the dielectric layer220and the second internal electrode230are not formed, and a position and quantity of the first external electrodes300may be adjusted. In addition, the second opening110bis positioned except for the region where the first opening110ais positioned. Accordingly, the second internal electrodes230disposed across a plurality of second openings110bare connected to each other. Accordingly, by selecting the region where the second external electrode310is disposed from the region where the second opening110bis positioned, the position and quantity of the second external electrode310included in the capacitor10amay be adjusted.