KR102551763B1 - Color filter including IGZO(Indium-Gallium-Zinc-Oxide) and method for manufacturing the same - Google Patents

Abstract

According to one aspect of the present invention, in a color filter including a plurality of color filter elements, the color filter elements may include: a plurality of metal layers provided to face each other; a dielectric layer provided between the metal layers and made of a material capable of transmitting light; and a color filter including Indium-Gallium-Zinc-Oxide (IGZO) provided on an upper side or a lower side of the dielectric layer and including an active layer including IGZO.

Description

Color filter including IGZO (Indium-Gallium-Zinc-Oxide) and method for manufacturing the same}

The present invention relates to a color filter containing IGZO (Indium-Gallium-Zinc-Oxide) and a method for manufacturing the same.

A technology that produces color using only specific structural characteristics without dyes or inks can be defined as structural color technology. A lot of research has been conducted on a color filter technology that extracts only a specific color by transmitting or reflecting light to a device capable of producing such a structural color.

Structural color filter technology not only can express all the colors that can be expressed with existing dyes or inks, but also has the advantage of having robust color characteristics in ultra-high resolution of 100,000 dpi and various external environments.

However, this structural color filter technology has a disadvantage in that it is a passive optical element whose characteristics are difficult to change once the device is manufactured.

In order to overcome this, conventionally, efforts to implement variable characteristics using liquid crystals or phase change materials (eg, VO2 or Ge2Sb2Te5) have been reported.

However, these materials have disadvantages in that a high concentration is required to cause a phase change and the range of modifiable colors is very limited because the change in refractive index in the visible ray region where color characteristics appear is not large.

In addition, technologies capable of modulating colors based on non-solid materials such as liquid crystals or hydrogels have been reported, but these materials have disadvantages in that the color range is limited by physical properties and it is difficult to precisely control the color.

Embodiments of the present invention are proposed to solve the above problems, and provide a color filter provided in an all-solide-state that can adjust the refractive index by adjusting the charge concentration of IGZO and a manufacturing method thereof want to do

In addition, it is intended to provide a color filter capable of exhibiting very vivid colors and a manufacturing method thereof.

In addition, an object of the present invention is to provide a highly efficient transmission type color filter having a very small loss with an extinction coefficient close to 0 in the visible ray wavelength region and a method for manufacturing the same.

According to one aspect of the present invention, in a color filter including a plurality of color filter elements, the color filter elements include: a plurality of metal layers provided to face each other; a dielectric layer provided between the metal layers and made of a material capable of transmitting light; and a color filter including Indium-Gallium-Zinc-Oxide (IGZO) provided on an upper side or a lower side of the dielectric layer and including an active layer including IGZO.

In addition, a color filter including indium-gallium-zinc-oxide (IGZO) in which a structural color displayed in the color filter element is changed according to the charge concentration of IGZO provided to the active layer may be provided.

In addition, a color filter including indium-gallium-zinc-oxide (IGZO) in which the dielectric layer is provided with silicon dioxide and the metal layer is provided with silver (Ag) may be provided.

In addition, a color filter including Indium-Gallium-Zinc-Oxide (IGZO) in which the dielectric layer is provided with a thickness of 40 nm to 180 nm and the active layer is provided with a thickness of 20 nm to 60 nm may be provided.

In addition, the active layer may be provided with a color filter including Indium-Gallium-Zinc-Oxide (IGZO) that is provided transparently to transmit light.

In addition, the active layer may be provided with a color filter including indium-gallium-zinc-oxide (IGZO) having an absorption coefficient of 0 to 0.01 in the visible ray region.

In addition, the color filter includes a plurality of color filter elements, and at least some of the plurality of color filter elements have different thicknesses, and a color filter including IGZO (Indium-Gallium-Zinc-Oxide) may be provided. .

In addition, the color filter includes a plurality of color filter elements, and at least some of the plurality of color filter elements are color filters containing IGZO (Indium-Gallium-Zinc-Oxide) provided with different charge concentrations. It can be.

In addition, a color filter including indium-gallium-zinc-oxide (IGZO) that causes resonance between a plurality of metal layers when light in a visible ray wavelength region is irradiated onto the color filter element may be provided.

In addition, the color filter element may be provided with a color filter including indium-gallium-zinc-oxide (IGZO) provided as an all-solid material.

According to one aspect of the present invention, manufacturing one metal layer (S1); Stacking a dielectric layer on one side of the metal layer (S2); Stacking an active layer containing IGZO on one side of the dielectric layer (S3); Stacking another metal layer on one side of the active layer (S4), and stacking an active layer including IGZO on one side of the dielectric layer (S3) is RF sputtering using an IGZO target in an Ar atmosphere. A method of manufacturing a color filter including indium-gallium-zinc-oxide (IGZO) performed by may be provided.

In addition, between the step of stacking a dielectric layer on one side of the metal layer (S2) and the step of stacking an active layer including IGZO on one side of the dielectric layer (S3), the dielectric layer may be provided with a portion having a different thickness. A method of manufacturing a color filter including indium-gallium-zinc-oxide (IGZO) including the step of performing an FIB milling process may be provided.

In addition, the composition ratio of the IGZO target may be provided with a method of manufacturing a color filter including IGZO (Indium-Gallium-Zinc-Oxide) provided in 1:1:1 mol % of In:Ga:Zn.

In addition, a color filter including indium-gallium-zinc-oxide (IGZO) having a resonant wavelength of light passing through the color filter element in the visible ray wavelength range of 55 nm to 65 nm may be provided.

A color filter containing IGZO (Indium-Gallium-Zinc-Oxide) and a method for manufacturing the same according to embodiments of the present invention are all-solide-state in which the refractive index can be adjusted by adjusting the charge concentration of IGZO. A provided color filter may be provided.

In addition, there is an advantage of providing a color filter capable of displaying very vivid colors.

In addition, there is an advantage in that a highly efficient transmission type color filter having an extinction coefficient close to 0 in the visible light wavelength region and a very small loss can be provided.

1 is a diagram conceptually illustrating a color filter 1 including indium-gallium-zinc-oxide (IGZO) according to an embodiment of the present invention.
FIG. 2 shows when the charge concentration of IGZO provided to the active layer 100 is changed in the color filter 1 including IGZO (Indium-Gallium-Zinc-Oxide) of FIG. 1 and the thickness of the dielectric layer 200 It is a diagram schematically showing the change in structural color when it is changed.
FIG. 3 is a transmission spectrum plot before and after hydrogen plasma treatment according to the thickness change of the dielectric layer 200 in the color filter 1 including IGZO (Indium-Gallium-Zinc-Oxide) of FIG. 1 plot).
FIG. 4 is an atomic force microscope (AFM) image showing the color filter 1 including indium-gallium-zinc-oxide (IGZO) of FIG. 1 including color filter elements 10 having different heights.
5 is a chromaticity diagram showing changes in structural color before and after performing a hydrogen plasma treatment process on IGZO in the color filter 1 containing IGZO (Indium-Gallium-Zinc-Oxide) of FIG. 1. am.
FIG. 6 is a graph showing a simulated transmission spectrum according to the thickness of the dielectric layer 200 in the color filter 1 including indium-gallium-zinc-oxide (IGZO) of FIG. 1 .
FIG. 7 shows the color filter 1 including indium-gallium-zinc-oxide (IGZO) of FIG. 1 before and after performing a hydrogen plasma treatment process on the active layer 100 according to an embodiment of the present invention. Shows the transmission spectrum.
FIG. 8 is a diagram showing an actual image appearing on the color filter 1 including indium-gallium-zinc-oxide (IGZO) of FIG. 1 .
9 is a graph showing the refractive index according to hydrogen plasma treatment conditions.
10 is a graph showing changes in refractive index and extinction coefficient according to the charge density of IGZO.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

In addition, in describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description will be omitted.

1 is a diagram conceptually showing a color filter 1 including indium-gallium-zinc-oxide (IGZO) according to an embodiment of the present invention, and FIG. In the color filter 1 including Oxide, it is a diagram schematically showing changes in structural color when the charge concentration of IGZO provided to the active layer 100 is changed and when the thickness of the dielectric layer 200 is changed. 3 is a transmission spectrum plot before and after hydrogen plasma treatment according to the thickness change of the dielectric layer 200 in the color filter 1 including IGZO (Indium-Gallium-Zinc-Oxide) of FIG. 1 (transmission). spectrum plot), and FIG. 4 is an atomic force microscope showing a color filter 1 including indium-gallium-zinc-oxide (IGZO) of FIG. 1 including color filter elements 10 having different heights ( AFM) image, and FIG. 5 is the structural color of the color filter 1 including indium-gallium-zinc-oxide (IGZO) of FIG. 1 before and after performing the hydrogen plasma treatment process on IGZO. 6 is a chromaticity diagram showing the change, and FIG. 6 shows a simulated transmission spectrum according to the thickness of the dielectric layer 200 in the color filter 1 including indium-gallium-zinc-oxide (IGZO) of FIG. FIG. 7 is a hydrogen plasma treatment process for the active layer 100 of the color filter 1 including the indium-gallium-zinc-oxide (IGZO) of FIG. 1 according to an embodiment of the present invention. Shows the transmission spectrum before and after execution, and FIG. 8 is a diagram showing an actual image appearing on the color filter 1 including IGZO (Indium-Gallium-Zinc-Oxide) of FIG. 1, and FIG. 9 is hydrogen It is a graph showing the refractive index according to the plasma treatment (hydrogen plasma treatment) conditions, and FIG. 10 is a graph showing the change in the refractive index and extinction coefficient according to the charge density of IGZO.

1 to 10, a color filter 1 including indium-gallium-zinc-oxide (IGZO) according to an embodiment of the present invention includes a plurality of color filter elements 10, and each In the color filter element 10 , the first metal layer 310 , the dielectric layer 200 , the active layer 100 , and the second metal layer 320 may be sequentially stacked.

Here, the first metal layer 310 and the second metal layer 320 may be understood as the metal layer 300 , and the dielectric layer 200 and the active layer 100 may be provided between the metal layers 300 .

In addition, IGZO can be understood as an amorphous semiconductor composed of indium, gallium, zinc, and oxygen.

IGZO (Indium-Gallium-Zinc-Oxide, Igzo) of this embodiment is provided to the active layer 100, and the refractive index of light having a visible ray wavelength range by changing the charge concentration of IGZO provided to the active layer 100 ( refractive index) can be adjusted, and accordingly, the color filter element 10 operating in the visible light wavelength region can provide.

In addition, the structural color of the color filter element 10 may be changed according to the charge concentration of IGZO provided to the active layer 100 .

In addition, the color filter 1 including indium-gallium-zinc-oxide (IGZO) may be provided as an all-solid state.

The charge concentration of IGZO may be adjusted through a hydrogen plasma treatment process, and thus the conductivity of the active layer 100 may be adjusted. A more detailed description of this will be given later.

In addition, a transmission type color filter capable of displaying vivid colors can be provided by the color filter element 10 having a Fabry-Perot type resonant nanostructure including IGZO.

In addition, the color filter 1 including such IGZO (Indium-Gallium-Zinc-Oxide) can change the structural color using a doped semiconductor, that is, doped IGZO, and is an all-solide- state) and can be manufactured to have a large-area.

In addition, the color filter 1 including IGZO (Indium-Gallium-Zinc-Oxide) has an advantage in that it can be manufactured without lithography as will be described later.

The color filter 1 including such IGZO (Indium-Gallium-Zinc-Oxide) may be used for anti-counterfeiting display technology, low-power reflective display, and the like.

The metal layer 300 may include a first metal layer 310 and a second metal layer 320 facing each other, and a color filter including indium-gallium-zinc-oxide (IGZO) in the metal layer 300 facing each other. Resonance of light passing through (1) occurs. That is, it may be understood that the first metal layer 310 and the second metal layer 320 serve as mirrors in the FP resonator.

For example, the metal layer 300 may be made of silver (Ag), and each metal layer 300 may have a thickness of 10 nm to 60 nm, preferably 30 nm.

The dielectric layer 200 may be provided between the metal layers 300 and made of a material capable of transmitting light.

For example, the dielectric layer 200 may be provided with silicon dioxide (SIO ₂ ).

In addition, the color filter 1 containing IGZO (Indium-Gallium-Zinc-Oxide) includes a plurality of color filter elements 10, and at least some of the plurality of color filter elements 10 have different thicknesses. It can be.

For example, the dielectric layer 200 may have a thickness t1 of 10 nm to 300 nm, preferably 40 nm to 180 nm.

Specifically, the thickness of the color filter element 10 may be adjusted according to the thickness t1 of the dielectric layer 200, and the structural color appearing in the color filter element 10 may change according to the thickness t1 of the dielectric layer 200. It can be.

The color filter 1 containing Indium-Gallium-Zinc-Oxide (IGZO) may be provided by arranging a plurality of color filter elements 10 side by side, and the color filter 1 containing Indium-Gallium-Zinc-Oxide (IGZO) may be provided. By differently adjusting the thickness of the plurality of color filter elements 10 provided in the filter 1, the structural color represented by the color filter 1 including IGZO (Indium-Gallium-Zinc-Oxide) can be changed. Here, the thickness of the color filter element 10 may be adjusted by an FIB milling process to be described later.

A more specific description of the change in the structural color of the color filter element 10 according to the thickness t1 of the dielectric layer 200 is as follows.

2(a) shows the thickness t1 of the dielectric layer 200 when hydrogen plasma treatment is not applied to the IGZO provided in the color filter element 10 (when the charge concentration is low, low doping). It shows the change in structural color that appears by changing. Here, the low charge concentration can be understood when the charge concentration is 10 ¹⁴ cm ^-3 or less.

Specifically, referring to FIG. 2(a), the structural color appearing in the first color filter element 10a is the structural color appearing in the second color filter element 10b when the thickness of the dielectric layer 200 is 40 nm. When the thickness of (200) is 60 nm, the structural color appearing in the third color filter element 10c is the structural color appearing in the fourth color filter element 10d when the thickness of the dielectric layer 200 is 80 nm. When the thickness is 100 nm, the structural color appearing in the fifth color filter element 10e is when the thickness of the dielectric layer 200 is 120 nm, and the structural color appearing in the sixth color filter element 10f is when the thickness of the dielectric layer 200 is 140 nm. , the structural color appearing in the seventh color filter element 10g indicates when the thickness of the dielectric layer 200 is 160 nm, and the structural color appearing in the eighth color filter element 10h indicates when the thickness of the dielectric layer 200 is 180 nm. Here, the thickness of each metal layer 300 is 30 nm, and the thickness of the active layer 100 is provided as 40 nm.

In addition, (b) of FIG. 2 shows the thickness (t1) of the dielectric layer 200 when hydrogen plasma treatment is performed on the IGZO provided in the color filter element 10 (when the charge concentration is high, high doping) It shows the change in structural color that appears by changing . 10a', 10b', 10c', 10d', 10e', 10f', 10g', 10h' are the thicknesses of the dielectric layer 200 of 10a, 10b, 10c, 10d, 10e, 10f, 10g, and 10h, respectively. same. Here, the high charge concentration can be understood when the charge concentration is 8x10 ¹⁹ cm ^-3 or more.

Also, as the thickness t1 of the dielectric layer 200 increases, the wavelength may be shifted to the red side (Red shifted).

In this way, by changing the thickness t1 of the dielectric layer 200 provided on the color filter element 10, the structural color represented by each color filter element 10 is changed, and IGZO (Indium-Gallium-Zinc-Oxide The color filter 1 including ) may represent various colors.

FIG. 4 shows an atomic force microscope (AFM) image showing the color filter 1 including indium-gallium-zinc-oxide (IGZO) of FIG. 1 including color filter elements 10 having different heights.

Each color filter element 10 may have a pixel size of 1um x 1um, and it can be seen that the thickness (or depth shown in FIG. 4 ) of the color filter element 10 varies according to encoded information.

The active layer 100 may be provided between a plurality of metal layers 300 provided to face each other, and may be provided above or below the dielectric layer 200 . Here, the active layer 100 is understood as a layer including IGZO.

The active layer 100 may have a thickness t2 of 20 nm to 60 nm, preferably 40 nm.

By controlling the charge concentration of IGZO in the active layer 100, a resonance wavelength (preferably, 60 nm) of 55 nm to 65 nm in the visible ray wavelength range of light passing through the color filter element 10 can be generated. The charge concentration of such IGZO may be adjusted by a hydrogen plasma treatment process described later.

As the charge concentration of IGZO provided to the active layer 100 is changed, the refractive index of light having a visible ray wavelength range can be adjusted.

Specifically, as the charge concentration of IGZO increases, the refractive index decreases, which decreases the optical path length, thereby providing a blue shift of the resonance peak, that is, control of the structural color.

In addition, (a) of FIG. 6 shows a simulated transmission spectrum when the dielectric layer 200 is 60 nm, and (b) of FIG. 6 shows a simulated transmission spectrum when the dielectric layer 200 is 80 nm.

Referring to (a) of FIG. 6, when the dielectric layer 200 is 60 nm, it can be seen that the structural color of the color filter element 10 changes from green to blue by subjecting IGZO to hydrogen plasma treatment.

At this time, the change in resonance wavelength appearing in the color filter element 10 before and after the execution of the hydrogen plasma treatment process is 60 nm.

Referring to (b) of FIG. 6, when the dielectric layer 200 is 80 nm, it can be seen that the structural color of the color filter element 10 changes from light green to green by subjecting IGZO to hydrogen plasma treatment.

At this time, the change in resonance wavelength appearing in the color filter element 10 before and after the execution of the hydrogen plasma treatment process is 52 nm.

In addition, referring to FIG. 5, it can be seen that the structural color shown in the color filter element 10 is changed by subjecting IGZO to a hydrogen plasma treatment process (initial is before the hydrogen plasma treatment process, Final after hydrogen plasma treatment process).

In addition, (a) of FIG. 3 shows a transmission spectrum plot before hydrogen plasma treatment according to the thickness change of the dielectric layer 200, and (b) of 3 shows a hydrogen plasma treatment. A transmission spectrum plot after treatment) is shown.

Referring to FIG. 7, when the dielectric layer 200 is 120 nm, the transmission spectrum before and after applying the hydrogen plasma treatment process to the dielectric layer 200 is shown (before doping is hydrogen plasma treatment) treatment), after doping is after hydrogen plasma treatment).

FIG. 8 is a diagram showing an actual image appearing on the color filter 1 including indium-gallium-zinc-oxide (IGZO) of FIG. 1 .

Specifically, in (a) of FIG. 8, hydrogen plasma treatment is not performed on each color filter element 10 of the color filter 1 including IGZO (Indium-Gallium-Zinc-Oxide). , and (b) of FIG. 8 is when hydrogen plasma treatment is performed on each color filter element 10 of the color filter 1 containing IGZO (Indium-Gallium-Zinc-Oxide). is an image of Here, the color filter element 10 may have a pixel size of 1um x 1um.

Hereinafter, a method of manufacturing the color filter 1 containing IGZO (Indium-Gallium-Zinc-Oxide) will be described in detail.

A method of manufacturing a color filter containing IGZO (Indium-Gallium-Zinc-Oxide) includes the steps of manufacturing one metal layer 300 (S1); Stacking a dielectric layer 200 on one side of the metal layer 300 (S2); Stacking an active layer 100 containing IGZO on one side of the dielectric layer 200 (S3); Stacking another metal layer 300 on one side of the active layer 100 (S4), and stacking the active layer 100 including IGZO on one side of the dielectric layer 200 (S3). ) may be performed by RF sputtering using an IGZO target in an Ar atmosphere (atmosphere).

Specifically, the step (S1) of manufacturing one metal layer 300 may include depositing silver (Ag) having a thickness of 30 nm at a deposition rate of 0.2 nm/s by electron beam evaporation. .

In addition, in the step (S2) of depositing the dielectric layer 200 on one side of the metal layer 300, silicon dioxide (SIO ₂ ) is deposited on one side of the silver (Ag) at a deposition rate of 1 nm/s by electron beam evaporation. It may include layering.

In addition, between the step (S2) of stacking the dielectric layer 200 on one side of the metal layer 300 and the step (S3) of stacking the active layer 100 including IGZO on one side of the dielectric layer 200, the dielectric layer ( A step in which FIB milling is performed on the dielectric layer 200 may be provided so that portions having different thicknesses t1 of 200 may be provided. Here, the portion where the thickness t1 of the dielectric layer 200 is different can be understood as each color filter element 10 described above.

For example, in the color filter 1 including IGZO (Indium-Gallium-Zinc-Oxide), when the dielectric layer 200 has 5 portions having different thicknesses t1, IGZO (Indium-Gallium-Zinc-Oxide) It can be understood that the color filter 1 including -Oxide includes 5 types of color filter elements 10 . However, these numbers are merely exemplary, and the part having a different thickness t1 of the dielectric layer 200, that is, the type of color filter element 10 may be provided infinitely. In this embodiment, the dielectric layer 200 has a different thickness t1, that is, two or more types of color filter elements 10, preferably five or more, may be provided.

The FIB milling process may be used to create micro-sized color filter elements 10, that is, color pixels and corresponding color images. In particular, in order to manufacture the color filter element 10 exhibiting different colors, the thickness of the dielectric layer 200, that is, the milling depth for each pixel must be different.

For example, to fabricate a color filter (1) containing IGZO (Indium-Gallium-Zinc-Oxide) representing 5 colors, 5 CAD files arranged in a rectangular array with a size of 1 μm Х 1 μm may be provided. there is.

In this embodiment, depositing the dielectric layer 200 of 180 nm and changing the ion milling time to adjust the thickness of the dielectric layer 200 will be described as an example. After the milling process, the active layer 100 and the metal layer 300 may be stacked.

Next, stacking the active layer 100 including IGZO on one side of the dielectric layer 200 (S3) may be performed by RF sputtering using an IGZO target in an Ar atmosphere.

Here, the composition ratio of the IGZO target may be 1:1:1 mol % of In:Ga:Zn.

After RF sputtering, the dielectric layer 200 may be annealed at 300 °C for 2 hours in an O ₂ atmosphere.

After that, hydrogen plasma treatment may be performed on the dielectric layer 200 .

For example, hydrogen plasma treatment can be performed at 120 °C in a plasma-enhanced chemical vapor deposition chamber for 5 min with an RF power of 200 W.

Referring to FIG. 9 , it can be seen that the refractive index of the color filter element 10 varies according to hydrogen plasma treatment conditions.

Specifically, FIG. 9 shows the refractive index according to the wavelength of light when the temperature of the hydrogen plasma treatment performed in the plasma-enhanced chemical vapor deposition chamber is 50 °C, 120 °C, and 300 °C.

Hereinafter, the principle of controlling the charge concentration by hydrogen plasma treatment will be described in more detail.

In the color filter element 10, IGZO is an essential element for adjusting the refractive index.

As described above, a 40 nm thick transparent dielectric layer 200 containing IGZO was deposited, and the charge concentration (or charge density) was controlled by a hydrogen plasma treatment process.

Since the injected hydrogen atoms form an OH bond with ionized oxygen in IGZO, free electrons can be generated in H ₂ plasma as shown in (1) below.

The modulation of the refractive index of IGZO can be explained by the TL-Drude model (Tauc-Lorentz-Drude).

The TL-Drude model is a model previously used to model optical properties of oxide semiconductors such as ZnO and In ₂ O ₃ , and the dielectric constant of the TL-Drude model can be expressed as (2) below.

과

은 각각 TL 및 Drude models에 의해 주어진 유전상수로 이해될 수 있다. here,

class

can be understood as the dielectric constant given by TL and Drude models, respectively.

The dielectric constant of the TL term represents band-to-band energy absorption, and the Drude term represents free-electron absorption.

The Drude model is commonly used to analyze metallic materials, but it can be applied to doped IGZO because H ₂ plasma treatment increases the electron density similar to metallic materials.

In addition, the complex dielectric constant of the Drude model can be expressed as follows.

와

는 각각

의 실수 부분과 허수 부분을 나타낸다. 그리고,

와

는 각각 진폭(amplitude)과 확장매개변수(broadening parameter)를 나타낸다. here,

and

are respectively

represents the real and imaginary parts of and,

and

denotes an amplitude and a broadening parameter, respectively.

는 하기와 같이 표현될 수 있다. also,

can be expressed as follows.

는 플라즈마 에너지(plasma energy),

는 플랑크 상수,

는 플라즈마 각 주파수,

는 캐리어 농도(carrier concentration),

는 전하,

는 자유 공간 유전율(free-space permittivity)을 나타낸다. here,

is the plasma energy,

is Planck's constant,

is the plasma angular frequency,

is the carrier concentration,

is the charge,

represents the free-space permittivity.

The refractive index of IGZO can be obtained from the relationship between the dielectric constant and the refractive index as follows.

는 각각 복합 유전 상수에서 실수부분과 허수부분을 나타낸다. here,

denotes the real and imaginary parts of the complex dielectric constant, respectively.

이 감소하고

이 증가하기 때문에, 굴절률이 감소할 수 있다. According to the above equation (6), as the electron density increases,

is decreasing

As this increases, the refractive index may decrease.

Meanwhile, Ar bombardments during hydrogen plasma treatment cannot be ignored because it can break the oxygen bond and generate oxygen vacancies.

Oxygen vacancies act as deep-level traps so that the dielectric layer 200 including doped IGZO can absorb light with energy lower than the band gap. Referring to FIG. 10 , it can be seen that an extinction coefficient increases at an energy lower than the band gap.

In addition, Ar bombardme may reduce the refractive index by increasing the electron density of the dielectric layer 200 including IGZO due to oxygen vacancies.

It can be understood that the low conductivity IGZO sample had an electron density of less than 10 ¹⁴ cm ^-3 and the high conductivity film had an electron density of 8 Х 10 ¹⁹ cm ^-3 , and ellipsometry measurements were performed to extract the optical properties. .

As can be seen in FIG. 10, the refractive index changed to 0.4 in the visible light wavelength region, and the extinction coefficient also changed as the film conductivity changed. These results provide a principle to change the refractive index in solid thin films by changing the electron density. In addition, in order to implement an electrically controlled active index thin film, the electron density must be further controlled by voltage.

The color filter (1) containing IGZO (Indium-Gallium-Zinc-Oxide) takes the shape of an FP resonator as described above. The resonance condition of the FP resonator is determined by constructive and destructive interference between the metal layers 300 caused by a specific phase change when light is reflected within the resonator. This not only results in a very sharp resonance pea in the FP resonator, but also a high transmittance because the FP resonator does not rely on the use of plasmons.

Although the color filter including IGZO (Indium-Gallium-Zinc-Oxide) and its manufacturing method according to an embodiment of the present invention have been described as specific embodiments, this is only an example, and the present invention is not limited thereto, It should be construed as having the widest scope according to the basic idea disclosed herein. A person skilled in the art may implement a pattern of a shape not indicated by combining or substituting the disclosed embodiments, but this also does not deviate from the scope of the present invention. In addition, those skilled in the art can easily change or modify the disclosed embodiments based on this specification, and it is clear that such changes or modifications also fall within the scope of the present invention.

1: Color filter containing IGZO (Indium-Gallium-Zinc-Oxide)
10: color filter element
100: active layer
200: dielectric layer
300: metal layer

Claims (14)

In the color filter including a plurality of color filter elements,
The color filter element,
a plurality of metal layers provided to face each other;
a dielectric layer provided between the metal layers and made of a material capable of transmitting light; and
An active layer provided on the upper or lower side of the dielectric layer and including IGZO,
The active layer has an absorption coefficient of 0 to 0.01 in the visible ray region.
A color filter containing IGZO (Indium-Gallium-Zinc-Oxide). According to claim 1,
Structural color appearing in the color filter element is changed according to the charge concentration of IGZO provided in the active layer.
A color filter containing IGZO (Indium-Gallium-Zinc-Oxide). According to claim 1,
The dielectric layer is provided with silicon dioxide,
The metal layer is provided with silver
A color filter containing IGZO (Indium-Gallium-Zinc-Oxide). According to claim 1,
The dielectric layer is provided with a thickness of 40 nm to 180 nm,
The active layer is provided with a thickness of 20 nm to 60 nm.
A color filter containing IGZO (Indium-Gallium-Zinc-Oxide). According to claim 1,
The active layer is provided transparently to transmit light.
A color filter containing IGZO (Indium-Gallium-Zinc-Oxide). delete According to claim 1,
The color filter includes a plurality of color filter elements,
At least some of the plurality of color filter elements have a thickness
are provided differently
A color filter containing IGZO (Indium-Gallium-Zinc-Oxide). According to claim 1,
The color filter includes a plurality of color filter elements,
At least some of the plurality of color filter elements are provided with different charge concentrations of IGZO.
A color filter containing IGZO (Indium-Gallium-Zinc-Oxide). According to claim 1,
When the color filter element is irradiated with light in the visible ray wavelength range, resonance occurs between the plurality of metal layers.
A color filter containing IGZO (Indium-Gallium-Zinc-Oxide). According to claim 8,
The color filter element is provided as an all-solid
A color filter containing IGZO (Indium-Gallium-Zinc-Oxide). Manufacturing one metal layer (S1);
Stacking a dielectric layer on one side of the metal layer (S2);
Stacking an active layer containing IGZO on one side of the dielectric layer (S3);
And stacking another metal layer on one side of the active layer (S4),
Step (S3) of stacking an active layer containing IGZO on one side of the dielectric layer,
performed by RF sputtering using an IGZO target in an Ar atmosphere.
Method for manufacturing a color filter containing IGZO (Indium-Gallium-Zinc-Oxide). According to claim 11,
Between the step (S2) of stacking a dielectric layer on one side of the metal layer and the step (S3) of stacking an active layer including IGZO on one side of the dielectric layer,
performing an FIB milling process on the dielectric layer so that portions with different thicknesses of the dielectric layer can be provided.
Method for manufacturing a color filter containing IGZO (Indium-Gallium-Zinc-Oxide). According to claim 11,
The composition ratio of the IGZO target is provided as In: Ga: Zn 1: 1: 1 mol %
Method for manufacturing a color filter containing IGZO (Indium-Gallium-Zinc-Oxide). According to claim 1,
The resonance wavelength of light in the visible ray wavelength range passing through the color filter element is 55 nm to 65 nm.
A color filter containing IGZO (Indium-Gallium-Zinc-Oxide).

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