KR102322045B1 - Antenna device and display device including the same - Google Patents

Abstract

The present invention relates to an antenna device and an image display device including the same. The antenna device includes: a dielectric layer; and an antenna pattern formed on the dielectric layer, wherein the antenna pattern includes a calcium-containing copper layer containing 95 atomic% or more of calcium within 5% thickness from the outermost surface. The present invention provides the image display device including the antenna device having improved transmittance and signal sensitivity.

Description

Antenna element and image display device including the same

The present invention relates to an antenna element and an image display device including the same.

With the recent development of information and communication technology, wireless communication technologies such as Wi-Fi and Bluetooth are combined with an image display device, and are implemented in the form of, for example, a smart phone. In this case, an antenna may be coupled to the image display device to perform a communication function.

The antenna includes an antenna electrode and/or a pattern capable of transmitting and receiving a signal to perform a wireless communication function. Copper has good electrical conductivity due to its low price and low resistance, so it is suitable for use as a material for antenna electrodes and/or patterns. there is

Meanwhile, as mobile communication technology evolves in recent years, for example, an antenna for performing communication in a high-frequency or ultra-high frequency band needs to be coupled to the image display device. However, when the driving frequency of the antenna increases, signal loss may increase, and the degree of signal loss may further increase as the performance of the antenna decreases.

Therefore, it is necessary to develop an antenna capable of preventing performance degradation due to oxidation while maintaining excellent electrical conductivity of the antenna.

Korean Patent Registration No. 10-1718016 discloses an antenna unit having excellent light transmittance by introducing a conductive oxide film on the upper and lower portions of the metal conductive layer, but the problem of performance degradation due to oxidation of the metal conductive layer is still not solved.

Republic of Korea Patent Registration No. 10-1718016

An object of the present invention is to provide an antenna element that maintains reliability over time while maintaining excellent electrical conductivity characteristics.

Another object of the present invention is to provide an antenna element having improved transmittance and signal sensitivity.

Another object of the present invention is to provide an image display device including an antenna element that maintains reliability over time while maintaining excellent electrical conductivity characteristics.

Another object of the present invention is to provide an image display device including an antenna element having improved transmittance and signal sensitivity.

The present invention, a dielectric layer; and an antenna pattern formed on the dielectric layer, wherein the antenna pattern includes a calcium-containing copper layer containing 95 atomic% or more of calcium within a thickness of 5% from an outermost surface.

In the present invention, in the first aspect, the thickness of the calcium-containing copper layer may be 1000 to 3100 Å.

In the second aspect of the present invention, the antenna pattern may include a radiation pattern, a transmission line extending from the radiation pattern, and a signal pad connected to a distal end of the transmission line.

In the third aspect of the present invention, the radiation pattern, the transmission line, and the signal pad may include the calcium-containing copper layer.

In the fourth aspect of the present invention, the radiation pattern, the transmission line, and the signal pad may be disposed on the same level and formed through a substantially single process.

In the fifth aspect of the present invention, the radiation pattern and the transmission line may include a mesh structure.

According to the sixth aspect of the present invention, the mesh structure may include unit cells having a rhombus shape.

In the seventh aspect of the present invention, the antenna pattern may include a calcium-containing copper layer containing 95 atomic% or more of calcium within 4% thickness from the outermost surface.

In the eighth aspect of the present invention, the antenna pattern may include a calcium-containing copper layer containing 97 atomic% or more of calcium within 5% thickness from the outermost surface.

In the ninth aspect of the present invention, the calcium-containing copper layer is formed through a sputtering process, and the sputtering process may not use oxygen gas as a carrier gas.

In the tenth aspect of the present invention, the antenna pattern may have a laminate structure including a transparent conductive oxide layer and a calcium-containing copper layer.

Further, the present invention relates to an image display device comprising the above antenna element and a display panel.

According to the eleventh aspect, the present invention further comprises a flexible printed circuit board electrically connected to the antenna element and comprising a signal wire electrically connected to a signal pad of the antenna element, wherein the signal wire is calcium-containing copper It may include a layer.

In the antenna element of the present invention, since the antenna pattern includes a calcium-containing copper layer containing 95 atomic% or more of calcium on the outermost surface, it is possible to block oxygen from reaching the deep part of the calcium-containing copper layer, thereby oxidizing the copper layer. It is possible to prevent deterioration of antenna performance due to this. In addition, since calcium is contained in an amount of less than 5 atomic% other than the outermost surface of the calcium-containing copper layer, electrical conductivity similar to that of a pure copper layer can be exhibited.

1 and 2 are schematic plan and cross-sectional views showing an antenna element according to an embodiment of the present invention.
3 is a schematic plan view showing an antenna element according to another embodiment of the present invention.
4 and 5 are schematic cross-sectional views and plan views illustrating an image display apparatus according to an embodiment of the present invention.
6 is a view showing the calcium and oxygen content of each depth of the calcium-containing copper layer according to an embodiment of the present invention.
7 is a view showing the surface oxidation evaluation criteria according to the experimental example of the present application.

The present invention relates to a dielectric layer; and an antenna pattern formed on the dielectric layer, wherein the antenna pattern includes a calcium-containing copper layer containing 95 atomic% or more of calcium within 5% thickness from the outermost surface, and an image display device including the same. .

In the antenna element of the present invention, since the antenna pattern includes a calcium-containing copper layer containing 95 atomic% or more of calcium on the outermost surface, it is possible to block oxygen from reaching the deep part of the calcium-containing copper layer, thereby oxidizing the copper layer. It is possible to prevent deterioration of antenna performance due to this. In addition, since calcium is contained in an amount of less than 5 atomic% other than the outermost surface of the calcium-containing copper layer, electrical conductivity similar to that of a pure copper layer can be exhibited.

The antenna element of the present invention can be universally used in a technical field using signal transmission and reception. For example, an antenna for 3G mobile communication (3G) to 5G high-frequency mobile communication (5G) and an image display device including the same may be used, and the scope of the present invention is not impaired even in the field of mobile communication to be developed later. can be used within

Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings. However, the following drawings attached to the present specification illustrate preferred embodiments of the present invention, and serve to further understand the technical idea of the present invention together with the above-described content of the present invention, so the present invention is described in such drawings It should not be construed as being limited only to the matters.

The terminology used herein is for the purpose of describing the embodiments, and is not intended to limit the present invention. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase.

As used herein, “comprises” and/or “comprising” refers to the presence or addition of one or more other components, steps, operations and/or components other than the stated components, steps, operations and/or components. It is used in the sense of not being excluded. Like reference numerals refer to like elements throughout.

Spatially relative terms “bottom”, “bottom”, “lower”, “top”, “top”, “upper”, etc. are one element or component and another element or component as shown in the drawings. It can be used to easily describe the correlation with The spatially relative terms should be understood as terms including different orientations of the device during use or operation in addition to the orientation shown in the drawings. For example, when an element shown in the drawings is turned over, an element described as "below" or "below" another element may be placed "above" the other element. Accordingly, the exemplary term “down” may include both the downward and upward directions. The device may also be oriented in other orientations, and thus spatially relative terms may be interpreted according to orientation.

1 and 2 are schematic plan and cross-sectional views showing an antenna element according to an exemplary embodiment.

1 and 2 , an antenna element according to an exemplary embodiment may include a dielectric layer 110 and an antenna pattern 120 formed on the dielectric layer, and the antenna pattern 120 is a calcium-containing copper layer. (121) may be included.

The dielectric layer 110 may serve to provide a structural base of components constituting the antenna element.

The dielectric layer 110 may include an insulating material having a predetermined dielectric constant, and a conventionally or later developed one may be used.

In one or more embodiments, the dielectric layer 110 includes an inorganic insulating material such as glass, silicon oxide, silicon nitride, or metal oxide, or an organic insulating material such as an epoxy resin, an acrylic resin, or an imide-based resin. may be doing

For example, a transparent film may be provided as the dielectric layer 110 .

In one or a plurality of embodiments, the transparent film includes a polyester-based resin such as polyethylene terephthalate, polyethylene isophthalate, polyethylene naphthalate, and polybutylene terephthalate; Cellulose resins, such as a diacetyl cellulose and a triacetyl cellulose; polycarbonate-based resin; acrylic resins such as polymethyl (meth)acrylate and polyethyl (meth)acrylate; styrenic resins such as polystyrene and acrylonitrile-styrene copolymer; polyolefin-based resins such as polyethylene, polypropylene, polyolefin having a cyclo-based or norbornene structure, and an ethylene-propylene copolymer; vinyl chloride-based resin; amide resins such as nylon and aromatic polyamide; imide-based resin; polyether sulfone-based resin; sulfone-based resins; polyether ether ketone resin; sulfide polyphenylene-based resin; vinyl alcohol-based resin; vinylidene chloride-based resin; vinyl butyral-based resin; allylate-based resin; polyoxymethylene-based resins; A thermoplastic resin such as an epoxy-based resin may be included. These may be used alone or in combination of two or more. In addition, a transparent film made of a thermosetting resin such as (meth)acrylic, urethane, acrylic urethane, epoxy, or silicone or UV curable resin may be used as the dielectric layer 110 .

In one embodiment, the dielectric layer 110 may be provided as a substantially single layer. In one embodiment, the dielectric layer 110 may include a multi-layer structure of at least two or more layers.

In one embodiment, the dielectric constant of the dielectric layer 110 may be adjusted in the range of 1.5 to 12. When the dielectric constant exceeds 12, the driving frequency is excessively reduced, so that driving in a desired high frequency band may not be realized.

The antenna pattern 120 may be formed on the upper surface of the dielectric layer 110 . For example, the plurality of antenna patterns 120 may be arranged in an array form along the width direction of the dielectric layer 110 or the antenna element 100 to form an antenna pattern row.

The antenna pattern 120 may include a calcium-containing copper layer 121 , and the calcium-containing copper layer 121 may serve as an electrode for transmitting and receiving signals.

In one embodiment, the calcium-containing copper layer 121 may contain 95 atomic% or more of calcium within 5% thickness from the outermost surface.

Copper is used as a material for antenna electrodes and/or patterns because of its low price and excellent electrical conductivity due to low resistance. However, copper is easily oxidized in contact with oxygen when exposed to air. Since oxidized copper does not conduct electricity, electrical conductivity is significantly reduced when a portion of the copper layer is oxidized. Therefore, in order to prevent deterioration of antenna characteristics, it is necessary to prevent oxidation of the copper layer.

The calcium-containing copper layer 121 of the present invention is characterized in that calcium is concentrated and distributed in the outermost layer 121a at 95 atomic% or more, preferably 97 atomic% or more, more preferably 99 atomic% or more. The outermost layer 121a may be 5% thick from the outermost surface of the calcium-containing copper layer 121, preferably 4% thick from the outermost surface, and most preferably 3% thick from the outermost surface. can be part As such, when calcium is concentrated in the outermost layer 121a, it is possible to block oxygen in the air from penetrating into the lower copper layer 121b (a portion of the calcium-containing copper layer except for the outermost layer), so that the lower copper layer 121b) oxidation can be fundamentally prevented.

Unlike the present invention, when calcium is distributed throughout the copper layer, oxygen in the air cannot be blocked from penetrating into the copper layer. Accordingly, oxidation of the copper layer proceeds with the lapse of time, and deterioration of antenna characteristics cannot be prevented.

The calcium-containing copper layer 121 may be formed through a sputtering process. The sputtering process may include depositing the dielectric layer 110 using a CuCa target after loading it into a sputtering process chamber, and argon (Ar) gas may be used as a carrier gas.

In one embodiment, the sputtering process may be performed without oxygen gas as a carrier gas, that is, without oxygen partial pressure. As the sputtering process is performed using the CuCa target in the absence of oxygen partial pressure, it is preferable because a calcium-containing copper layer containing 95 atomic% or more of calcium can be formed within 5% of the thickness from the outermost surface.

When a sputtering process is performed using a CuCa target in a state in which partial pressure of oxygen is applied, calcium is not distributed intensively on the outermost surface, but is distributed throughout the copper layer, and the resulting problems are as described above.

In one embodiment, the thickness of the calcium-containing copper layer 121 may be 1000 to 3100 Å, preferably 1500 to 2500 Å. It is preferable because sufficient signal transmission and electrical conductivity through the calcium-containing copper layer can be implemented within the thickness range.

The antenna pattern 120 may include a radiation pattern 122 and a transmission line 124 . The radiation pattern 122 may have, for example, a polygonal plate shape, and the transmission line 124 may extend from one side of the radiation pattern 122 . The transmission line 124 is formed as a single member substantially integral with the radiation pattern 122 , and may have a narrower width than the radiation pattern 122 .

The antenna pattern 120 may further include a signal pad 126 . The signal pad 126 may be connected to a distal end of the transmission line 124 . In an embodiment, the signal pad 126 is provided as a member substantially integral with the transmission line 124 , and the distal end of the transmission line 124 may be provided as the signal pad 126 .

In an embodiment, the radiation pattern 122 , the transmission line 124 , and the signal pad 126 may include a copper-calcium alloy, which will be described later. For example, the radiation pattern 122 , the transmission line 124 , and the signal pad 126 may include substantially the same copper-calcium alloy.

In an embodiment, the radiation pattern 122 , the transmission line 124 , and the signal pad 126 are disposed on the same level on the dielectric layer 110 and may be formed through a substantially single process. In this case, since it is formed on the same level in a single process using substantially the same member (eg, the calcium-containing copper layer), the process is simplified and the manufacturing cost of the antenna element 100 can be reduced.

According to some embodiments, a ground pad 128 may be disposed around the signal pad 126 . For example, a pair of ground pads 128 may be disposed to face each other with the signal pad 126 interposed therebetween. The ground pad 128 may be electrically and physically separated from the transmission line 124 and the signal pad 126 .

The signal pad 126 and the ground pad 128 may be formed in a solid pattern formed of the above-described metal or alloy in consideration of reduction in feeding resistance, noise absorption efficiency, and improvement in horizontal radiation characteristics.

The antenna pattern 120 or the radiation pattern 122 may be designed to have, for example, a resonance frequency of 3G, 4G, 5G or higher high-frequency or ultra-high frequency band. For example, the resonant frequency of the antenna pattern 120 may be in the range of about 20 to 40 GHz.

In an embodiment, radiation patterns 122 having different sizes may be arranged on the dielectric layer 110 . In this case, the antenna element 100 may be provided as a multi-radiation or multi-band antenna radiating in a plurality of resonant frequency bands.

In an embodiment, the radiation pattern 122 and the transmission line 124 may include a mesh-pattern structure to improve transmittance. In this case, a dummy mesh pattern (not shown) may be formed around the radiation pattern 122 and the transmission line 124 . When the radiation pattern 122 and/or the transmission line 124 includes a mesh structure, the visibility and sheet resistance of the electrode pattern may be reduced, the transmittance of the electrode pattern may be increased, and the flexibility of the antenna element may be improved. can be Accordingly, the antenna element can be effectively used in a flexible display device.

The mesh structure may include a radiation unit cell in which a pair of adjacent first electrode lines and a pair of adjacent second electrode lines cross each other. In an embodiment, the radiation unit cell may have a substantially rhombus shape, but is not limited thereto and may have a polygonal shape such as a hexagon.

In an embodiment, the radiation pattern 122 may have a mesh-pattern structure, and at least a portion of the transmission line 124 may include a solid metal pattern.

The radiation pattern 122 may be disposed in a display area of the image display apparatus, and the signal pad 126 and the ground pad 128 may be disposed in a non-display area or a bezel area of the image display apparatus. At least a portion of the transmission line 124 may also be disposed in the non-display area or the bezel area.

In an embodiment, the antenna pattern 120 may include a transparent conductive oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (ITZO), or zinc oxide (ZnOx).

In an embodiment, the antenna patterns 120 may include a stacked structure of a transparent conductive oxide layer and a metal layer, and the metal layer may be a calcium-containing copper layer. For example, it may have a two-layer structure of a transparent conductive oxide layer - a metal layer or a metal layer - a transparent conductive oxide layer, or a three-layer structure of a transparent conductive oxide layer - a metal layer - a transparent conductive oxide layer. In this case, while the flexible characteristic is improved by the metal layer, the signal transmission speed may be improved by lowering the resistance, and the corrosion resistance and transparency may be improved by the transparent conductive oxide layer.

The antenna pattern 120 may include a blackening processing unit. Accordingly, the reflectance on the surface of the antenna pattern 120 may be reduced, and thus pattern recognition due to light reflection may be reduced.

In an embodiment, the blackening layer may be formed by converting the surface of the metal layer included in the antenna pattern 120 into a metal oxide or metal sulfide. In an embodiment, a blackening layer such as a black material coating layer or a plating layer may be formed on the antenna pattern 120 or the metal layer. The black material or plating layer may include silicon, carbon, copper, molybdenum, tin, chromium, molybdenum, nickel, cobalt, or an oxide, sulfide, or alloy containing at least one of these.

The composition and thickness of the blackening layer may be adjusted in consideration of the reflectance reduction effect and antenna radiation characteristics.

The calcium-containing copper layer 121 may be disposed on the dielectric layer 110 . For example, the calcium-containing copper layer 121 may be in contact with the dielectric layer 110 , or another member may be interposed between the calcium-containing copper layer 121 and the dielectric layer 110 .

3 is a schematic plan view showing an antenna element according to another embodiment of the present invention.

Referring to FIG. 3 , the antenna element 100 may be electrically connected to the flexible printed circuit board 200 .

The flexible printed circuit board 200 may include a core layer 210 and signal wires 220 formed on surfaces of the core layer 210 .

In some embodiments, the dielectric layer 110 may be provided as the flexible printed circuit board 200 . In this case, the flexible printed circuit board 200 (eg, the core layer 210 of the flexible printed circuit board 200 ) may be provided as a member substantially integral with the dielectric layer 110 . In addition, the signal wiring 220 to be described later is directly connected to the transmission line 124 , and the signal pad 126 may be omitted.

The core layer 210 may include, for example, a flexible resin such as polyimide resin, modified polyimide (MPI), epoxy resin, polyester, cycloolefin polymer (COP), liquid crystal polymer (LCP), or the like. The core layer 210 may include an internal insulating layer included in the circuit board 200 .

The signal wires 220 may be provided as, for example, power feed lines. The signal wires 220 may be arranged on one surface (eg, a surface facing the antenna pattern 120 ) of the core layer 210 .

For example, the flexible printed circuit board 200 is formed on the one surface of the core layer 210 and may further include a coverlay film covering the signal wires.

The signal wires 220 may be connected or bonded to the signal pads 126 of the antenna patterns 120 . For example, one end of the signal wires 220 may be exposed by partially removing the coverlay film of the flexible printed circuit board 200 . One end of the exposed signal wires 220 may be bonded to the signal pad 126 .

For example, after attaching a conductive bonding structure such as an anisotropic conductive film (ACF) on the signal pads 126 , the bonding region BR of the flexible printed circuit board 200 on which the signal wires 220 and the ends are located. ) may be disposed on the conductive bonding structure. Thereafter, the bonding region BR of the flexible printed circuit board 200 may be attached to the antenna element 100 through a heat treatment/pressurization process, and the signal wires 220 are electrically connected to each signal pad 126 . can be connected

As shown in FIG. 3 , each of the signal wires 220 may be independently connected or bonded to each of the signal pads 126 of the antenna patterns 120 . In this case, power and control signals may be independently supplied from the antenna driving integrated circuit (IC) chip 290 to each antenna pattern 120 .

In an embodiment, a predetermined number of antenna patterns 120 may be coupled through the signal wire 220 .

In an embodiment, the signal wiring 220 may include the above-described calcium-containing copper layer. In this case, oxidation can be suppressed by preventing oxygen from reaching the deep part of the signal wiring 220 while preventing the conductivity of the signal wiring 220 from being too low. Accordingly, it is possible to implement the signal wiring 220 with high reliability while preventing loss of a signal transmitted through the signal wiring 220 .

In exemplary embodiments, an intermediary circuit board 280 is disposed on the flexible printed circuit board 200 , and an antenna driving IC chip 290 on the intermediary circuit board 280 is, for example, surface mounted technology. (SMT) can be mounted.

The term “intermediate circuit board” used in the present application may generically refer to a circuit structure or circuit board positioned between the flexible printed circuit board 200 and the antenna driving IC chip 290 .

For example, the intermediate circuit board 280 may include a main board of an image display device, a rigid printed circuit board, and various antenna package boards.

When the intermediate circuit board 280 is a rigid printed circuit board, for example, the intermediate circuit board 280 may have higher strength or lower ductility than the flexible printed circuit board 200 . Accordingly, the mounting stability of the antenna driving IC chip 290 can be improved. For example, when the intermediate circuit board 280 is a rigid printed circuit board, a resin (eg, epoxy resin) layer impregnated with an inorganic material such as glass fiber, such as a prepreg, is formed as a base insulating layer or a core. It is included as a layer and may include signal wires distributed on and inside the base insulating layer.

A power supply and driving signal may be applied from the antenna driving IC chip 290 to the antenna pattern 120 through the signal wiring 220 . For example, a circuit or contact electrically connecting the antenna driving IC chip 290 and the signal wiring 220 may be further included in the flexible printed circuit board 200 .

4 and 5 are schematic cross-sectional views and plan views, respectively, for explaining an image display apparatus according to example embodiments.

4 and 5 , the image display device 300 may be implemented in the form of, for example, a smart phone, and FIG. 5 illustrates a front part or a window surface of the image display device 300 . The front portion of the image display device 300 may include a display area 310 and a peripheral area 320 . The peripheral area 320 may correspond to, for example, a light blocking part or a bezel part of the image display device.

The antenna element 100 included in the above-described antenna package may be disposed toward the front of the image display device 300 , for example, on the display panel 305 . In an embodiment, the radiation patterns 122 may at least partially overlap the display area 310 .

In this case, the radiation pattern 122 may include a mesh-pattern structure, and a decrease in transmittance due to the radiation pattern 122 may be prevented. The pads 126 and 128 included in the antenna pattern 120 are formed of a solid metal pattern, and may be disposed in the peripheral area 320 to prevent image quality deterioration.

In some embodiments, the flexible printed circuit board 200 is bent along the side curvature profile of the display panel 305 to be disposed on the rear surface of the image display device 300 , for example, and the antenna driving IC chip 290 . It may extend toward the mounted intermediate circuit board 280 (eg, the main board).

The flexible printed circuit board 200 and the intermediate circuit board 280 are bonded or interconnected through a connector, so that power supply to the antenna element 100 by the antenna driving IC chip 290 and control of the antenna driving can be implemented.

Hereinafter, examples of the present invention will be specifically described. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims.

<Examples and Comparative Examples>: Antenna element fabrication

Example 1

After loading a glass substrate into a sputtering process chamber (chamber temperature: 120° C.) and starting deposition using a CuCa (Cu to Ca ratio: 1 atomic%) target, Ar gas is injected at a total pressure of 0.3 to 0.4 Pa to contain calcium. A copper layer was formed to a thickness of 2000 Å.

Comparative Example 1

After loading a glass substrate into a sputtering process chamber (chamber temperature: 120° C.) and starting deposition using a CuCa (Cu to Ca ratio: 1 atomic%) target, 10/10 sccm of oxygen gas as a carrier gas, a total of 20 sccm It was injected together with Ar at a pressure of 0.5 to 0.7 Pa to form a calcium-containing copper layer to a thickness of 2000 Å.

Comparative Example 2

After loading a glass substrate into a sputtering process chamber (chamber temperature: 120°C), and starting deposition using a CuCa (Cu to Ca ratio: 1 atomic%) target, 40/40 sccm of oxygen gas as a carrier gas, a total of 80 sccm It was injected together with Ar at a pressure of 0.5 to 0.7 Pa to form a calcium-containing copper layer to a thickness of 2000 Å.

Comparative Example 3

After loading a glass substrate into a sputtering process chamber (chamber temperature: 120° C.) and starting deposition using a pure Cu 100% target, Ar gas was injected at a total pressure of 0.3 to 0.7 Pa to form a pure copper metal layer to a thickness of 2000 Å.

<Experimental example>

1. Analysis of calcium (Ca) content by depth

Specimens were prepared by cutting the calcium-containing copper layer according to Example 1 and Comparative Examples 1 and 2 to a size of 1 cm * 1 cm. For the prepared specimens, the calcium (Ca) content was analyzed by depth using an X-ray photoelectron spectrometer (Quantera II, Ulvac-PHI), and the results are shown in Table 1 and FIG. 6 below. The calcium (Ca) content for each depth in Table 1 below represents the calcium (Ca) content (atomic %) for each depth with respect to the total calcium (Ca) atoms contained in the calcium-containing copper layer.

<Conditions for component analysis>

- Analysis equipment: X-ray photoelectron spectroscopy (XPS), Quantera II, manufactured by Ulvac-PHI

- Vacuum reached: 3.8 x 10-7 Torr

- Excitation source: monochromatic Al Kα (1486.6 eV)

- Output: 50 W, 15kV

- Detection area: 200 μmφ

- Incident angle: 45°

- Take-out angle: 45°

- Pass energy: 55eV

- Heavy gun: 1.0V, 20.0も

- Elements to be analyzed: Copper (Cu), Oxygen (O), Calcium (Ca)

[Ca content by depth (atomic%)] Depth (nm) depth(%) Example 1 Comparative Example 1 Comparative Example 2 0 (surface) 0 (surface) 96.0 2.7 3.3 6.25 3.13 4.0 2.3 4.4 12.5 6.25 0 1.9 3.7 18.75 9.38 0 2.3 2.9 25 12.50 0 3.3 2.7 31.25 15.63 0 3.3 2.1 37.5 18.75 0 3.2 2.1 43.75 21.88 0 3.7 2.8 50 25.00 0 2.0 2.6 56.25 28.13 0 4.0 2.3 62.5 31.25 0 4.5 4.4 (skip) (skip) (skip) (skip) (skip) 200 100 0 1.8 2.9

Referring to Table 1, in the calcium-containing copper layer according to Example 1 of the present application, it can be confirmed that most of the calcium atoms are distributed within 5% of the thickness from the outermost surface.

On the other hand, in the calcium-containing copper layers according to Comparative Examples 1 and 2, it can be confirmed that calcium atoms are distributed in a similar content at all depths including the outermost surface. Comparative Example 3 did not measure the calcium content in the pure copper layer.

2. Electrical conductivity evaluation

Specimens were prepared by cutting the calcium-containing copper layer or the pure copper layer according to Example 1 and Comparative Examples 1 to 3 to a size of 1 cm * 1 cm. With respect to the prepared specimen, electrical conductivity was measured using a Hall effect measurement system (HMS), and the results are shown in Table 2 below.

3. Reliability Assessment

Specimens were prepared by cutting the calcium-containing copper layer or the pure copper layer according to Example 1 and Comparative Examples 1 to 3 to a size of 1 cm * 1 cm. After heating the prepared specimen in an oven at 90° C. for 192 hours, the surface color change compared to before heating was analyzed, and reliability was evaluated according to the following criteria, and the results are shown in Table 2 below.

The surface color change was observed through visual observation, a camera and an optical microscope.

<Reliability Evaluation Criteria>

◎: No change in surface color (refer to '◎' in FIG. 7)

○: Almost no change in surface color (refer to '○' in FIG. 7)

△: Color change occurs on a part of the surface (refer to '△' in FIG. 7)

×: Color change occurs over the entire surface (refer to 'x' in FIG. 7)

4. Evaluation of Antenna Characteristics

For the antenna elements according to Example 1 and Comparative Examples 1 to 3, initial antenna characteristics (S parameters) and '3. Each of the antenna characteristics after 'reliability evaluation' was evaluated, and the results are shown in Table 2 below. Specifically, the device is a probe contact method, and the S parameter S11 is evaluated by measuring the input/output change of the current with respect to the antenna pattern.

electrical conductivity
(1/Ωcm) Reliability evaluation Antenna characteristics (gain) Early After reliability evaluation Example 1 2.21E+05 ○ 7.7 dBi 7.7 dBi Comparative Example 1 8.37E+04 × 7.2 dBi 6.4 dBi Comparative Example 2 2.62E+04 × 6.8 dBi 6.1 dBi Comparative Example 3 3.62E+05 △ 8.0 dBi 7.5 dBi

Referring to the results of Table 2, the antenna element of Example 1 including a calcium-containing copper layer containing 95 atomic% or more of calcium within 5% thickness from the outermost surface, Comparative Example 1 including calcium throughout the copper layer And it can be seen that the antenna element exhibits superior electrical conductivity, reliability, and antenna characteristics compared to the antenna elements of 2 . In addition, it can be seen that the antenna element of Example 1 of the present application exhibits similar electrical conductivity as that of the antenna element of Comparative Example 3 including a pure copper layer, while exhibiting superior reliability and antenna characteristics. On the other hand, although the initial antenna characteristics of Comparative Example 3 including a pure copper layer not containing calcium were good, it can be confirmed that the antenna characteristics were deteriorated due to oxidation of the copper layer after reliability evaluation.

100: antenna element 110: dielectric layer
120: antenna pattern 121: calcium-containing copper layer
121a: outermost layer 121b: lower copper layer
122: radiation pattern 124: transmission line
126: signal pad 128: ground pad
200: flexible circuit board 210: core layer
220: signal wiring 280: intermediate circuit board
290: antenna driving IC chip 300: image display device
305 display panel 310 display area
320: surrounding area

Claims (13)

dielectric layer; and
comprising an antenna pattern formed directly on the dielectric layer;
The antenna pattern includes a calcium-containing copper layer containing 95 atomic% or more of calcium within 5% thickness from the outermost surface,
The calcium-containing copper layer is formed through a sputtering process,
The sputtering process will not use oxygen gas as a carrier gas, the antenna element. The method according to claim 1, The thickness of the calcium-containing copper layer is 1000 to 3100 Å, the antenna element. The antenna element according to claim 1, wherein the antenna pattern includes a radiation pattern, a transmission line extending from the radiation pattern, and a signal pad connected to a distal end of the transmission line. The antenna element according to claim 3, wherein the radiation pattern, the transmission line, and the signal pad include the calcium-containing copper layer. The antenna element according to claim 4, wherein the radiation pattern, the transmission line, and the signal pad are disposed on the same level and formed through a substantially single process. The antenna element according to claim 3, wherein the radiation pattern and the transmission line include a mesh structure. The antenna element according to claim 6, wherein the mesh structure includes a rhombus-shaped unit cell. The antenna element according to claim 1, wherein the antenna pattern includes a calcium-containing copper layer containing 95 atomic% or more of calcium within 4% thickness from the outermost surface. The antenna element according to claim 1, wherein the antenna pattern includes a calcium-containing copper layer containing 97 atomic% or more of calcium within a thickness of 5% from the outermost surface. delete The antenna element according to claim 1, wherein the antenna pattern has a laminated structure including a transparent conductive oxide layer and a calcium-containing copper layer. An antenna element according to any one of claims 1 to 9 and 11; and a display panel. 13. The method of claim 12,
Further comprising: a flexible printed circuit board electrically connected to the antenna element and including a signal wire electrically connected to the signal pad of the antenna element;
and the signal wiring includes a calcium-containing copper layer.

Images