KR100449142B1 - Micro supercapacitor adopting carbon nanotubes and manufacturing method thereof - Google Patents

Abstract

A micro supercapacitor using carbon nanotubes and a method of manufacturing the same are disclosed. Micro supercapacitor according to an aspect of the present invention, two electrodes of a thin film comprising carbon nanotubes opposed to each other, introduced between the two electrodes, but filled between the carbon nanotubes Li ₃ PO ₄ , LiPO ₃ , LiBO ₂ , LiO ₂ , B ₂ O ₃ , V ₂ O ₅ , P ₂ O ₅ , SiO ₂ or a mixture of thin films of solid electrolyte, and chromium, platinum, copper, Provided are a micro supercapacitor including current collectors of a thin film made of aluminum or nickel.

Description

Micro supercapacitor adopting carbon nanotubes and manufacturing method

TECHNICAL FIELD The present invention relates to energy storage and supply devices, and more particularly, to a micro supercapacitor including a thin film electrode formed using carbon nanotubes and a method of manufacturing the same.

Recently, with the development of scientific and industrial technology, the development of micro precision mechanical component devices or ultra-fine electrical and electronic devices has been rapidly progressing worldwide. In order to function and control such precision micro devices, it is required to develop an independent micro-sized energy supply device for driving precision micro devices. However, the technology for manufacturing such micro-sized energy supplies is still in its infancy worldwide.

An object of the present invention is to provide a micro-super capacitor that can be used as a power supply device of a fine size.

Another object of the present invention is to provide a method of manufacturing a micro-super capacitor that can be used as a power supply device of a fine size.

1 to 5 are schematic views for explaining a micro-super capacitor and a method of manufacturing the same according to an embodiment of the present invention.

<Brief description of the major symbols in the drawings>

100; Substrates 210, 250; House,

310, 350; Carbon nanotube thin film electrode,

400: solid electrolyte, 500; Protective coating.

One aspect of the present invention for achieving the above technical problem, provides a micro supercapacitor comprising two electrodes of a thin film comprising carbon nanotubes facing each other, and a solid electrolyte of the thin film introduced between the two electrodes. .

The electrode may further include a material forming the solid electrolyte filled between the carbon nanotubes. The material forming the solid electrolyte may be Li ₃ PO ₄ , LiPO ₃ , LiBO ₂ , LiO ₂ , B ₂ O ₃ , V ₂ O ₅ , P ₂ O _5, or SiO ₂ .

The solid electrolyte may be composed of Li ₃ PO ₄ , LiPO ₃ , LiBO ₂ , LiO ₂ , B ₂ O ₃ , V ₂ O ₅ , P ₂ O ₅ , SiO _2, or a mixture thereof.

Each of the electrodes may further include current collectors of a thin film formed on a rear surface facing the solid electrolyte and made of chromium, platinum, copper, aluminum, or nickel.

One aspect of the present invention for achieving the above another technical problem, to form a first electrode of a thin film comprising carbon nanotubes on a substrate, to form a solid electrolyte of the thin film on the first electrode, the solid It provides a method of manufacturing a micro supercapacitor comprising forming a second electrode of a thin film comprising carbon nanotubes on an electrolyte.

The first electrode and the second electrode may be deposited by sputtering, thermal vapor deposition, or vacuum vapor deposition using carbon nanotubes as samples. In this case, the sample may further include a material forming the solid electrolyte mixed in the carbon nanotubes. The material forming the solid electrolyte of the sample may include Li ₃ PO ₄ , LiPO ₃ , LiBO ₂ , LiO ₂ , B ₂ O ₃ , V ₂ O ₅ , P ₂ O _5, or SiO ₂ .

The solid electrolyte may be formed by sputtering a sample including Li ₃ PO ₄ , LiPO ₃ , LiBO ₂ , LiO ₂ , B ₂ O ₃ , V ₂ O ₅ , P ₂ O ₅ , SiO _2, or a mixture thereof. The method may include depositing on the first electrode by thermal vapor deposition or vacuum vapor deposition. At this time, the evaporation may be included, or performed in an atmosphere containing N ₂ or O ₂ and N _2, or including the O _2.

A first collector of a thin film made of chromium, platinum, copper, aluminum, or nickel is formed on the substrate to be introduced between the first electrode and the substrate, and chromium, platinum, copper, aluminum, or the like is formed on the second electrode. The method may further include forming a second current collector of the thin film made of nickel.

The forming of the first electrode, the forming of the solid electrolyte, and the forming of the second electrode may be continuously performed.

According to the present invention, it is possible to provide a micro supercapacitor that can be used as a micro-scale energy storage and supply device by thinning two electrodes made of carbon nanotubes and a solid electrolyte.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, embodiments of the present invention may be modified in many different forms, and the scope of the present invention should not be construed as being limited by the embodiments described below. Embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art. Accordingly, the shape and the like of the elements in the drawings are exaggerated to emphasize a more clear description, and the elements denoted by the same reference numerals in the drawings means the same elements. In addition, where a layer is described as being "on" another layer or semiconductor substrate, the layer may exist in direct contact with the other layer or semiconductor substrate, or a third layer therebetween. May be interposed.

In an embodiment of the present invention, a micro-sized supercapacitor is formed using carbon nanotubes.

Carbon nanotubes are several nanometers to several tens of nanometers in diameter and tens of micrometers to hundreds of micrometers in length, which are largely anisotropic in structure and have various shapes in the form of single walls, multi walls, or bundles. Have Carbon nanotubes are mechanically strong, have excellent chemical stability, and have high thermal and electrical conductivity.

In the embodiment of the present invention using the carbon nanotubes to provide a bar forming a thin film electrode. In this case, the carbon nanotube thin film has a thickness of about 1 μm or less and is used as an electrode of the micro super capacitor. Carbon nanotubes are deposited on a medium by sputtering, thermal evaporation, or vacuum evaporation, to form a thin film electrode. Conventional carbon-based electrode materials are known to be difficult to form by thinning, but in the embodiment of the present invention, since the carbon nanotubes may be formed as thin films, the size of the supercapacitor may be reduced.

By employing such a carbon nanotube thin film electrode, the characteristics showing the high specific surface area of the carbon nanotubes can be used for improving the characteristics of the supercapacitor. That is, the individual carbon nanotubes have a hollow tube shape, so that electrolyte ions can be easily occluded, and there are many seats in which electrolyte ions can be occluded between the carbon nanotubes and the carbon nanotubes. Therefore, when the supercapacitor is formed by forming the carbon nanotubes as thin film electrodes, the charge / discharge capacity of the battery may be increased and high repeatability may be realized. Thus, by using a carbon nanotube thin film electrode, it becomes possible to provide a high performance micro super capacitor.

Meanwhile, an embodiment of the present invention proposes a micro-supercapacitor by using a carbon nanotube thin film electrode and by thinning ion conductors in a completely solid state to use as a solid electrolyte.

1 is a view schematically illustrating a micro supercapacitor according to an embodiment of the present invention.

In detail, the micro-supercapacitor using the supercapacitor concept according to the embodiment of the present invention is formed by thinning carbon nanotubes and positioned between the electrodes 310 and 350 facing each other and the electrodes 310 and 350. The solid electrolyte 400 is introduced in the form of a thin film.

On the reverse side of the solid electrolyte 400 of each of the electrodes 310 and 350, a current collector 210 for applying a charge to the electrodes 310 and 350 or drawing out a charge generated from the electrodes 310 and 350. 250 may be introduced in the form of a thin film. The first current collector 210, the first electrode 310, the solid electrolyte 400, the second electrode 350, and the second current collector 250 may be sequentially stacked on the substrate 100. Can be configured. The passivation layer 500 may be introduced onto the second current collector 250.

The electrodes 310 and 350 are made of a thin film made of a plurality of single or multiwalled carbon nanotubes. The electrodes 310 and 350 may be formed in a thin film form by sputtering, thermal vapor deposition, or vacuum vapor deposition. In this case, each of the electrodes 310 and 350 may be formed as a thin film having a thickness of about 1 μm or less. It is preferable.

The current collectors 210 and 250, which are respectively introduced to the rear surfaces of the electrodes 310 and 350, are introduced to effectively apply or draw voltage or current to the electrode 300, and are formed of conductive materials such as chromium, platinum, copper, aluminum, It may be made of a thin film such as nickel. Such materials are deposited in thin films by sputtering, thermal vapor deposition or vacuum vapor deposition. The current collectors 210 and 250 are preferably formed of a thin film having a thickness of about 1 μm or less.

The solid electrolyte 400 is formed in a thin film form, and the solid electrolyte 400 may be formed of ion conductors, for example, Li ₃ PO ₄ , LiPO ₃ , LiBO ₂ , LiO ₂ , B ₂ O ₃ , V ₂ O ₅ , P ₂ O ₅ or SiO ₂ may be made alone or mixed. This solid electrolyte 400 is introduced to prevent short circuits between the electrodes 310 and 350 and to allow free ion exchange.

As such, when a current and a voltage are applied to each of the thin film electrodes 310 and 350 of the supercapacitor including the electrodes 310 and 350 of the carbon nanotube thin film and the solid electrolyte 400 of the thin film, the solid electrolyte 400 The ions within are separated into anions (−) and cations (+) and move to the two electrodes 310 and 350, respectively. As a result, the potential between the two electrodes 310 and 350 is changed to generate electricity.

Meanwhile, each of the electrodes 310 and 350 is made of carbon nanotubes, but the solid electrolyte 400 is interposed between the carbon nanotubes in order to further promote free ion exchange with the solid electrolyte 400. Consisting materials, such as ion conductors, can be formed in a homogeneous mixture. That is, the electrodes 310 and 350 may be made of materials forming the carbon nanotubes and the solid electrolyte 400 homogeneously filled between the carbon nanotubes. Examples of materials constituting the solid electrolyte 400 include, for example, Li ₃ PO ₄ , LiPO ₃ , LiBO ₂ , LiO ₂ , B ₂ O ₃ , V ₂ O ₅ , P ₂ O _5, or SiO ₂ as ionic conductors. Can be. As such, the materials constituting the solid electrolyte 400 included in the electrodes 310 and 350, for example, the ion conductors, serve as a passage through which ions of the solid electrolyte 400 can move to the electrodes 310 and 350 more quickly. .

The passivation layer 500 is formed by depositing an insulating material or the like to protect the supercapacitor configured as described above. At this time, one end of each of the first current collector 210 and the second current collector 250 is exposed to the outside of the range of the protective film 500, and then induced to be electrically contacted with other connection wires.

2 to 5 are schematic views for explaining a method of manufacturing a micro-super capacitor according to an embodiment of the present invention in detail.

2 schematically illustrates a step of forming the first current collector 210 on the substrate 100.

Specifically, the substrate 100 made of an insulating material or the like is introduced into a chamber (not shown) of the deposition equipment. The first current collector 210 is formed by depositing a conductive material such as chromium, platinum, copper, aluminum, nickel, or the like on the substrate 100 to form a thin film. Such deposition may be performed by sputtering, thermal vapor deposition or vapor deposition. The thin film by such deposition is formed to a thickness of about 1 μm or less.

Meanwhile, the patterning of the thin film may use various thin film patterning methods. For example, after deposition of the thin film may be patterned using a photolithography method or the like, or before depositing the thin film, a first mask (first mask) 601 is introduced onto the substrate 100, and then the The thin film may be patterned by depositing a thin film on the substrate and removing or removing the first mask 601 from the substrate 100.

3 schematically illustrates a step of forming the first electrode 310 on the first current collector 210.

Specifically, the first electrode 310 is formed by depositing carbon nanotubes on the first current collector 210 of the thin film. The deposition of such carbon nanotubes may be performed by thermal vapor deposition, sputtering or vacuum vapor deposition. For example, after forming a target using the synthesized carbon nanotubes, the target is sputtered to deposit sputtered carbon nanotubes on the first current collector 210 of the thin film, whereby the carbon nanotube thin film To form. Alternatively, in the case of thermal vapor deposition, a carbon nanotube thin film is formed by vaporizing a sample of the synthesized carbon nanotubes with heat and depositing them on the first current collector 210. Alternatively, in the case of vacuum vapor deposition, a carbon nanotube thin film is formed by charging a sample of the synthesized carbon nanotubes in a vacuum chamber and forming a vacuum to vaporize the carbon nanotubes and depositing them on the first current collector 210. . Such carbon nanotube thin films are preferably deposited to a thickness of at most 1 μm for the formation of micro supercapacitors.

Meanwhile, the patterning of the carbon nanotube thin film may be performed in various ways, but before the deposition of the carbon nanotube thin film, the second mask 602 selectively exposing the position where the first electrode 310 is to be formed is formed on the substrate ( After being introduced onto 100, the carbon nanotube thin film can be patterned by depositing a carbon nanotube thin film thereon as described above and leaving or removing the second mask 602 from the substrate 100.

When the first electrode 310 of the carbon nanotube thin film is formed, a portion of the first current collector 210 is formed of carbon in order to connect a conductor to which voltage or current is subsequently applied or drawn to the first current collector 210. The first electrode 310 of the nanotube thin film may be exposed without being completely covered.

Meanwhile, although the first electrode 310 may be formed of a thin film made of carbon nanotubes as described above, free ion exchange with a solid electrolyte (400 in FIG. 1) to be formed on the first electrode 310 may be performed. In order to facilitate, a material for forming a solid electrolyte (400 in FIG. 1) may be further added between the carbon nanotubes.

For example, in the preparation step of performing the deposition process for forming the first electrode 310, the carbon nanotubes may be mixed with an ion conductor material that may be used as a solid electrolyte (400 of FIG. 1). When forming a thin film for the first electrode 310 by the sputtering method, Li ₃ PO ₄ , LiPO ₃ , LiBO ₂ , LiO ₂ , B ₂ O ₃ , V ₂ O ₅ , P ₂ O ₅ on the carbon nanotubes Alternatively, a target may be prepared by further mixing SiO ₂ alone or in mixture. Thereafter, by sputtering using the target to form a thin film, the first electrode 310 may include carbon nanotubes and ion conductors filled between the carbon nanotubes.

When the thin film for the first electrode 310 is formed by thermal vapor deposition or vacuum vapor deposition, a material, such as an ion conductor, for example, which forms the solid electrolyte (400 in FIG. 1) on the carbon nanotubes Li ₃ PO ₄ , LiPO ₃ , LiBO ₂ , LiO ₂ , B ₂ O ₃ , V ₂ O ₅ , P ₂ O _5, or SiO ₂ are further mixed in the form of a mixture alone or in advance to prepare a sample for vapor deposition. Thereafter, the sample may be vaporized and deposited to form a thin film so that the first electrode 310 may include carbon nanotubes and ion conductors filled between the carbon nanotubes.

As such, the materials forming the solid electrolyte (400 of FIG. 1), such as ion conductors homogeneously filled between the carbon nanotubes of the first electrode 310, are the carbon nanotubes and the solid electrolyte (400 of FIG. 1). ) To promote ion exchange, i.e., the role of the ions of the solid electrolyte (400 in Figure 1) to move faster into the carbon nanotubes.

4 schematically illustrates a step of sequentially forming the solid electrolyte 400 on the first electrode 310.

Specifically, after forming the first electrode 310, the solid electrolyte 400 is deposited on the first electrode 310 to form a thin film. In this case, the solid electrolyte 410 may be a single ion conductor, for example, Li ₃ PO ₄ , LiPO ₃ , LiBO ₂ , LiO ₂ , B ₂ O ₃ , V ₂ O ₅ , P ₂ O _5, or SiO ₂ alone or in combination. It may consist of a mixture. In this case, the solid electrolyte 400 may be formed by sputtering, thermal vapor deposition, or vacuum vapor deposition. That is, the thin film of the solid electrolyte 400 may be formed by sputtering using the ion conductors as a target or by vapor deposition using samples made of the ion conductors.

The patterning of the solid electrolyte 400 of the thin film may be performed by various patterning methods. For example, a mask that selectively exposes a portion of the solid electrolyte 400 to be deposited on the substrate 100 when the deposition is performed. After introducing (not shown) in advance, the patterned solid electrolyte 400 thin film can be obtained by performing vapor deposition and then removing or leaving the mask.

On the other hand, it is desirable to introduce these to perform the deposition of the solid electrolyte 400, a mood or atmosphere, or O ₂ and the deposition process the atmosphere of a mixed gas of N ₂ containing N ₂ containing O _2. This is to induce oxygen or nitrogen atoms to be introduced into the solid electrolyte 400 during the deposition process, thereby further increasing the ionic conductivity of the solid electrolyte 400. Accordingly, the ionic conductivity of the deposited solid electrolyte 400 may be obtained with a value between approximately 10 ⁻⁵ S / cm and 10 ⁻⁶ S / cm.

On the other hand, such a solid electrolyte 400 may be deposited to a thickness of about 1 ㎛ or less appropriately in a micro-sized super capacitor.

5 schematically illustrates a step of forming the second electrode 350 on the solid electrolyte 400.

Specifically, the second electrode 350 is formed on the solid electrolyte 400 as a thin film including carbon nanotubes. The deposition of the carbon nanotubes may be performed by thermal vapor deposition, sputtering, or vacuum vapor deposition, as in the deposition of the carbon nanotube thin film for the first electrode 310 described with reference to FIG. 3. As such, the second electrode 350 including the carbon nanotubes deposited as a thin film is preferably deposited to a thickness of about 1 μm or less to be suitable for use in a micro supercapacitor.

Meanwhile, the patterning of the carbon nanotube thin film may be performed in various ways, but before depositing the carbon nanotube thin film, a mask (not shown) that selectively exposes a position at which the second electrode 350 is to be formed is coated with a substrate ( After being introduced onto 100, the carbon nanotube thin film can be patterned by depositing a carbon nanotube thin film thereon and removing or removing the mask from the substrate 100.

On the other hand, the second electrode 350 may be made of a thin film made of carbon nanotubes as described above, in order to further promote free ion exchange with the solid electrolyte 400 of the lower solid electrolyte between the carbon nanotubes Further materials to make up 400 may be added. Depositing the second electrode 350 to further include a material for forming the solid electrolyte 400 may be performed by the same method as the method of forming the first electrode 310 described above.

Thereafter, a second current collector 250 is formed by depositing a conductive material, for example, chromium, platinum, copper, aluminum, nickel, or the like, on the rear surface of the second electrode 350 to form a thin film. Such deposition may be performed by sputtering, thermal vapor deposition or vapor deposition. The thin film by such deposition is formed to a thickness of about 1 μm or less.

Thereafter, as shown in FIG. 1, the passivation layer 500 is formed on the second current collector 250 by using an insulating material or the like. In this case, the passivation layer 500 may be patterned to expose an end of the first current collector 210 and a part of the second current collector 250. A conductive wire may be connected to the exposed first current collector 210 and the second current collector 250.

Meanwhile, the process of depositing the first current collector 210, the first electrode 310, the solid electrolyte 400, the second electrode 350, and the second current collector 250 as described above is performed in one process. It can be done continuously.

The micro-supercapacitor using the two electrodes 310 and 350 of the thin film manufactured as described above and the solid electrolyte 400 of the thin film uses the solid electrolyte 400 having an ion conductivity of approximately 10 ⁻⁵ S / cm. , It is measured that the specific storage capacity of approximately 3.5 × 10 ⁻¹ F / cm 2 · μm when charging and discharging at 2.5 V can be realized. In addition, the charging and discharging efficiency of repeated use shows high efficiency of almost 100%.

As mentioned above, although this invention was demonstrated in detail through the specific Example, this invention is not limited to this, It is clear that the deformation | transformation and improvement are possible by the person of ordinary skill in the art within the technical idea of this invention.

According to the present invention, a thin film of carbon nanotubes is used as an electrode of a micro supercapacitor, and at the same time a thin film of ion conductor is used as a solid electrolyte, a micro-supercapacitor which is a micro-sized energy storage and supply device can be manufactured. It is possible to provide a super capacitor having a thickness of about 3 μm or less. In addition, by depositing the carbon nanotubes simultaneously with the material forming the solid electrolyte, it is possible to manufacture a micro supercapacitor that maximizes the discharge capacity and charge and discharge efficiency by allowing ions to quickly diffuse into the electrode.

In addition, the micro-supercapacitor according to the present invention can be utilized as an independent energy supply device for ultra-precision precision mechanical component elements and ultra-fine electrical and electronic devices, and the effect of promoting the development of ultra-fine technologies can be expected.

Claims (13)

Two electrodes of a thin film comprising carbon nanotubes facing each other; Introduced between the two electrodes, but filled between the carbon nanotubes, Li ₃ PO ₄ , LiPO ₃ , LiBO ₂ , LiO ₂ , B ₂ O ₃ , V ₂ O ₅ , P ₂ O ₅ , SiO ₂ or their Thin film solid electrolyte consisting of a mixture; And And a thin film current collector made of chromium, platinum, copper, aluminum, or nickel on a rear surface of the electrode facing the solid electrolyte. delete delete delete delete Forming a first electrode of a thin film comprising carbon nanotubes on a substrate; Sputtering, heating a sample comprising Li ₃ PO ₄ , LiPO ₃ , LiBO ₂ , LiO ₂ , B ₂ O ₃ , V ₂ O ₅ , P ₂ O ₅ , SiO ₂ or a mixture thereof on the first electrode Depositing by vapor deposition or vacuum vapor deposition to form a thin solid electrolyte; Forming a second electrode of a thin film including carbon nanotubes on the solid electrolyte Forming a first current collector of a thin film made of chromium, platinum, copper, aluminum, or nickel on the substrate to be introduced between the first electrode and the substrate; And And forming a second current collector of a thin film made of chromium, platinum, copper, aluminum, or nickel on the second electrode. The method of claim 6, wherein the first electrode and the second electrode A method of manufacturing a micro supercapacitor, wherein the carbon nanotubes are deposited by sputtering, thermal vapor deposition, or vacuum vapor deposition. The method of claim 7, wherein the sample The method of claim 1, further comprising a material forming the solid electrolyte mixed with the carbon nanotubes. The method of claim 8, wherein the material constituting the solid electrolyte of the sample A method of manufacturing a micro supercapacitor comprising Li ₃ PO ₄ , LiPO ₃ , LiBO ₂ , LiO ₂ , B ₂ O ₃ , V ₂ O ₅ , P ₂ O ₅ or SiO ₂ . delete delete delete The method of claim 6, Forming the first electrode, forming the solid electrolyte, and forming the second electrode are successively performed.