KR101653744B1

KR101653744B1 - Light Detector and Imaging Device Containing the Same

Info

Publication number: KR101653744B1
Application number: KR1020090079721A
Authority: KR
Inventors: 김규식; 무수부 이치가와; 유스케 히가시
Original assignee: 삼성전자주식회사; 고쿠리츠 다이가쿠 호우징 신슈 다이가쿠
Priority date: 2009-08-27
Filing date: 2009-08-27
Publication date: 2016-09-05
Also published as: KR20110022228A

Abstract

As a technique related to a light receiving element including at least one color unit, by forming a light absorbing layer on the upper or lower portion of the color unit, it is possible to prevent the sensitivity of the color from decreasing and the effect of improving the color purity and contrast ratio. Further, since each color unit has a structure having a photoelectric conversion function by PN junction, it has a photoelectric conversion function, and therefore it is not necessary to use a separate color filter and a photodiode.

Description

(Light Detector and Imaging Device Containing the Same)

The present invention relates to an image pickup device such as a light receiving element and an image sensor including the same.

The light receiving element is widely used for digital cameras, broadcasting cameras, surveillance cameras, computer image cameras, camcorders, automotive sensors, home sensors, and solar cells. In general, a light receiving element has a structure in which pixels are arranged, and the pixel is basically composed of a microlens, a color filter, and a photoelectric conversion element.

In recent years, competition for the number of pixels for high image quality has intensified, thereby reducing pixel size has become a hot topic. However, as the pixel size decreases, the amount of light reaching the photodiode also decreases. Such a decrease in the amount of light is a factor that deteriorates the performance of the light receiving element such as sensitivity reduction, false color development, moire phenomenon, resolution degradation, and the like.

Conventionally, a MOS capacitor or a PN junction diode using a compound semiconductor such as crystalline silicon, amorphous silicon, or GaAs has been used as a photoelectric conversion element. Since such a photoelectric conversion element performs only photoelectric conversion, it is necessary to include a separate color filter in order to select a light receiving area.

Conventionally, the use of a color filter has insufficient color separation, low color purity, reproducibility, driving voltage, and the like. Accordingly, there is a need to provide a light receiving element excellent in color sensitivity and contrast effect.

Unlike the case where the light receiving element is constituted by separate photoelectric conversion elements and color filters in the prior art, these functions can be integrated and provide a color unit excellent in color sensitivity and contrast effect.

In one example, the light receiving element may have one or a plurality of color units stacked, each of the color units may selectively absorb a wavelength of a specific color, and the P-type organic material layer and the N- And a light absorbing layer including a light absorber capable of absorbing light of a desired wavelength is formed on an upper portion or a lower portion of the color unit.

The color unit may be, for example, a blue unit, a green unit, a red unit, or the like. Further, the light absorbing layer may include a light absorber that absorbs a wavelength other than the wavelength absorbed by the color unit formed at the lower portion thereof, or a light absorber that absorbs the wavelength absorbed by the color unit formed on the upper portion.

According to still another embodiment of the present invention, there is provided an element such as an imaging element including the light receiving element. The device may be, for example, a CCD image sensor or a CMOS image sensor.

In the color unit according to the embodiments of the present invention, the function of the photoelectric conversion element and the function of the color filter are integrated, and the wavelength selectivity of the color unit can be enhanced. Therefore, an image pickup device such as a CMOS image sensor including the same as a unit of a light receiving element can be stably sensed, and therefore, is excellent in economic efficiency and industrial utility value.

Hereinafter, advantages and features of the present invention and methods of performing the same will be more readily understood by reference to the following detailed description of the embodiments and the accompanying drawings. However, it should be understood that the present invention may be embodied in many other specific forms without departing from the spirit or scope of the invention.

The light receiving element according to one aspect has one or a plurality of color units stacked, each of the color units can selectively absorb a wavelength of a specific color, and the P-type organic material layer and the N-type organic material layer form a PN junction And a light absorbing layer including a light absorber capable of absorbing light of a desired wavelength is formed on an upper portion or a lower portion of the color unit.

In this way, when a predetermined light absorbing layer is formed, it is possible to prevent a specific wavelength leaked from reaching a color unit located at a lower portion by absorbing a specific wavelength emitted without being absorbed even though it should be absorbed in a color unit.

In another aspect, the wavelength selectivity can be increased by previously absorbing wavelengths other than the specific wavelength to be absorbed in the color unit. Therefore, it is possible to improve the sensitivity, purity and contrast ratio of color.

In this connection, Figs. 1 to 3 schematically show a cross-sectional view of a light-receiving element according to an aspect of the present invention. For convenience of explanation, the parts corresponding to Fig. 1 in Fig. 2-3 are denoted by the same reference numerals as those in Fig.

1, the extinction element 101 has a structure in which a blue unit 100, a green unit 200, and a red unit 300 are sequentially stacked from the light receiving surface side.

The color unit refers to a unit capable of selectively absorbing a wavelength of a specific color among visible light regions. Herein, the term " specific wavelength " means a wavelength selectively absorbed in a color unit. Here, the selective absorption means that the wavelength to be absorbed is mainly a desired wavelength, for example, 50% or more, 60% or more, or 70% or more. The approximate wavelength ranges according to color in the visible light region are shown in Table 1 below.

[Table 1]

Color Approximate wavelength
(in vacuum) Red (red) 780-622 Orange (orange) 597 to 622 Yellow 597-577 Green 577 ~ 492 Blue 492 to 455 Violet 455 to 390

Accordingly, the blue unit 100 can selectively absorb wavelengths of about 455 to 492 nm, and the green unit 200 can selectively absorb wavelengths of about 492 to 577 nm. Also, the red unit 300 can selectively absorb wavelengths of about 622 to 780 nm.

Above the color units 100, 200, and 300, light absorbing layers 410, 420, and 430 including a light absorber are formed. In the example of the present invention, since the wavelengths other than the specific wavelength absorbed by each color unit can be absorbed by the light absorbing layers 410, 420, and 430, wavelengths other than the specific wavelength can be prevented from reaching the color unit.

The method of forming the light absorbing layer is not particularly limited and may be performed using, for example, vapor deposition, spin coating, sol-gel method, or the like.

The positions where the light absorbing layers 410, 420, and 430 are formed may be the upper portion of the color unit or the lower portion of the color unit as shown in FIG. Further, when a plurality of color units are formed, they may be located therebetween.

For example, in a structure in which the blue unit 100, the green unit 200, and the red unit 300 are sequentially stacked, the light absorbing layer is composed of a light absorbing layer 410 for a blue unit, (420), and a red light absorbing layer (430).

A blue light absorbing layer 410 formed on the blue unit 100;

A light absorbing layer 420 for a green unit formed between the blue unit 100 and the green unit 200 or on the green unit 200;

A light absorbing layer 430 for a red unit formed between the green unit 200 and the red unit 300 or on the red unit 300.

The light absorbing layers 410, 420, and 430 are not necessarily formed, and either one of them may be formed. For example, as shown in FIG. 2, only a light absorbing layer 420 for a green unit and a light absorbing layer 430 for a red unit may be formed, and only a light absorbing layer 430 for a red unit is formed It is possible. In addition, an insulating layer (not shown) may be formed between the blue unit 100 and the green unit 200 in FIG. 3 as needed.

The light absorbing layers 410, 420, and 430 may include a light absorber that absorbs a desired wavelength, and a light absorber that absorbs wavelengths other than a specific wavelength band absorbed by the color unit formed at the lower portion thereof .

For example, the light absorbing layer 410 for a blue unit may be composed of a light absorber capable of absorbing light having a wavelength other than the blue wavelength, for example, longer than 492 nm. That is, the light absorber may be a material capable of absorbing light of a green, yellow, orange, or red wavelength.

The light absorbing layer 420 for a green unit may be composed of a light absorber capable of absorbing light having a shorter wavelength than 492 nm or absorbing light having a wavelength longer than 577 nm (e.g., yellow, orange, red).

The light absorbing layer 430 for the red unit may absorb light (for example, blue to green) having a wavelength other than the red wavelength region, for example, shorter than 600 nm, or light having a wavelength longer than 800 nm Absorbent material.

In yet another aspect, the light absorbing layer 410, 420, 430 may comprise a light absorber that selectively absorbs a particular wavelength absorbed in a color unit formed on top of it. In this case, the specific wavelength absorbed in the upper color unit can be absorbed when it is discharged downward. Therefore, it is possible to prevent the specific wavelength of the color unit located at the upper portion from being absorbed by the color unit located at the lower portion of the light absorbing layer, so that the color sensitivity is lowered.

The light absorber may be, for example, a coloring material having a complementary color relationship with the color of the color unit formed on the upper portion of the light absorbing layer containing the light absorber. Examples of the coloring material include, but are not limited to, organic dyes, organic pigments, and inorganic pigments.

For example, in the case of a laminated structure of blue, green and red, a light absorbing layer (first light absorbing layer) 420 formed under the blue unit 100 may be composed of a light absorbing material capable of absorbing a blue color wavelength . The light absorber may be, for example, a coloring material of a yellow-based color having a complementary relation to a blue color.

The blue unit 100 and the green unit 200 are formed on the upper portion of the light absorbing layer (second light absorbing layer) 430 formed on the lower portion of the green unit 200 to absorb the blue to green color wavelengths And the like. For example, it may be made of a colorant of a yellow-based color which is a complementary color to a blue color, and an orange-based or magenta-based color which is a complementary color to a green color.

Examples of the orange-based coloring materials include CdS (cadmium sulfide) -based pigments. Since the CdS or its derivative absorbs the blue wavelength, the light absorbing layer in which the CdS powder is dispersed is disposed at the upper portion or the lower portion of the blue unit 100 and / or the green unit 200 to prevent blue light from being transmitted to other color units . Therefore, the color sensitivity and the contrast can be increased.

The CdS pigment may be a material including ZnS (zinc sulfide), cadmium selenide, HgS (mercury sulfide), etc. in addition to CdS (cadmium sulfide). The CdS may have a particle diameter (D50) of several tens of nanometers to several tens of micrometers.

A green unit 200 and a red unit 300 are formed on an upper part of the light absorbing layer (third light absorbing layer; not shown) formed on the lower part of the red unit 300 Bar, and a light absorbing agent capable of absorbing blue to red color wavelengths.

The light absorbing layers 410, 420, and 430 may be formed separately or may be integrally formed with an insulating layer (not shown) formed between the plurality of color units 100, 200, and 300. For example, the light absorbing layer may include an insulating material, or the light absorbing layer may serve as an insulating layer by including a light absorbing agent in the insulating layer.

Each of the color units comprises a P-type organic material layer and an N-type organic material layer. Thus, a PN junction can be formed, thereby enabling photoelectric conversion. In addition, the P-type organic material layer or the N-type organic material layer may be formed using a material having selective transmittance of a wavelength so as to serve as a color filter. That is, the color unit may be a structure in which the functions of the photo diode and the color filter are integrated.

In this regard, Fig. 4 schematically shows a cross-sectional view of a color unit according to one aspect.

1 and 4, the color unit may have a structure in which a P-type organic material layer 111 and an N-type organic material layer 112 are sequentially stacked from the light receiving surface side, and the P-type organic material layer 111) or the N-type organic material layer 112 may be made of a light absorbing organic material capable of selectively absorbing only a desired wavelength. In this case, the P-type organic material layer is made of a light absorbing organic material that selectively absorbs only a desired wavelength, thereby achieving color selectivity.

For example, the blue unit 100 may include a P-type organic material layer deposited with TPD; And an N-type organic material layer deposited with C ₆₀ ; &Lt; / RTI >

In addition, an indoline layer (not shown) may be additionally formed between the P-type organic material layer 111 and the N-type organic material layer 112, as the case may be. For example, the green unit 200 may include a P-type organic material layer made of TPD; TPD and Me-PTC co-deposited; And an N-type organic material layer made of NTCDA; &Lt; / RTI >

In this structure, excitons are generated in the P-type organic material layer 111 by the light incident from the light receiving surface, and the P-type organic material layer 111 can selectively absorb light of a desired wavelength .

Fig. 5 schematically shows a cross-sectional view of a color unit according to another aspect.

1 and 5, the color unit includes a first P-type organic material layer 121 made of a light absorbing organic material capable of selectively absorbing a wavelength other than a desired wavelength; A second P-type organic material layer 122 made of a light absorbing organic material capable of selectively absorbing a desired wavelength, and an N-type organic material layer 123.

The first P-type organic material layer 121 is made of a light-absorbing organic material capable of selectively absorbing wavelengths other than a desired wavelength out of the visible light region, so that light of a desired wavelength range can be selectively transmitted . On the other hand, the second P-type organic material layer 122 may be made of a light absorbing organic material capable of absorbing a desired wavelength. The second P-type organic material layer 200 is not necessarily made of a material that absorbs only a desired wavelength but also includes an organic material capable of absorbing a wavelength in a whole region of visible light.

In some cases, a portion of the first P-type organic material layer 121 or the first P-type organic material layer 121 and the second P- An exciton blocking layer 124 may be formed.

In one example, the color unit comprises a first P-type organic material layer made of phenyl hexa thiophene (P6T); An exciton blocking layer made of Bi-phenyl-tri-thiophene (BP3T); A second P-type organic material layer made of CuPc; An N-type organic material layer made of C ₆₀ ; &Lt; / RTI >

The P6T is expressed by the following chemical formula (1), and has a band gap energy of about 2.1 eV, and can selectively absorb blue wavelengths of 400 to 500 nm. Therefore, it can be effectively used for the first P-type organic material layer 121 of the red unit.

(One)

Also, the BP3T is represented by the following chemical formula (2), and can effectively block the blue wavelength in the range of 400 to 550 nm. In addition, since the band gap energy is about 2.3 eV, which is about 0.2 eV higher than that of P6T, it can be effectively used for the exciton blocking layer 124 of the red unit.

(2)

The second P-type organic material layer 122 may be formed of a semiconductor material having a plurality of holes as carriers. Examples of organic materials that can be used for the P-type organic material layer include phthalocyanine derivatives and the like. In one example, CuPc (copper phthalocyanine) may be used for the second P-type organic material layer 122 as a light absorbing organic material capable of absorbing the wavelength in the entire visible light region.

The N-type organic material layer 123 may be made of a semiconductor organic material having a plurality of electrons. Examples of the material usable for the N-type organic material layer include C ₆₀ Fullerene Carbon.

Excitons are generated in the first and second P-type organic material layers 121 and 122 by the light incident from the light receiving surface in the color unit according to the present example, and the first P- The light of a desired wavelength is incident on the second P-type organic material layer 122. The second P-

In some cases, each of the color units 100, 200, and 300 may further include at least one layer selected from the following layers.

A first electrode layer formed on the P-type organic material layer;

A first buffer layer formed between the first electrode layer and the P-type organic material layer;

(3) an intrinsic layer formed between the P-type organic material layer and the N-type organic material layer and having a p-type organic material and an n-type organic material adhered to each other;

(4) a second electrode layer formed under the N-type organic material layer; And

(5) a second buffer layer formed between the N-type organic material layer and the second electrode layer.

For example, in the case where a light absorbing layer is formed on the color unit, it may be formed in various laminated structures (in order from the light receiving surface side) such as the following i to v.

(i) a light absorbing layer / a first electrode layer / a first buffer layer / a p-type organic material layer / a phosphor layer / an n-type organic material layer / a second buffer layer /

(ii) light absorbing layer / first electrode layer / P-type organic material layer / intrinsic layer / N-type organic material layer / second buffer layer / second electrode layer

(iii) absorbing layer / first electrode layer / first buffer layer / P-type organic material layer / intrinsic layer / N-type organic material layer / second electrode layer

(iv) absorbing layer / first electrode layer / P-type organic material layer / intrinsic layer / N-type organic material layer / second electrode layer

(v) absorbing layer / first electrode layer / P-type organic material layer / N-type organic material layer / second electrode layer

In the color unit of such a laminated structure, when a negative voltage is applied to the first electrode and a positive voltage is applied to the second electrode, and light is incident from the light receiving surface, excitons of electron and hole pairs are formed. Such excitons are formed in a large amount in the p-type electrode layer, and electrons can flow through the N-type organic material layer and / or the buffer layer to the second electrode layer to generate a current in a desired wavelength range.

The first electrode layer and the second electrode layer may be transparent electrodes, and the first electrode layer may have a larger work function (WF) than the second electrode layer. The transparent electrode material, e.g., ITO, IZO, ZnO, SnO 2, ATO (antimony-doped tin oxide), AZO (Al-doped zinc oxide), GZO (gallium-doped zinc oxide), TiO 2 and FTO ( fluorine-doped tin oxide). The second electrode layer may be a metal electrode made of a metal selected from the group consisting of Al, Cu, Ti, Au, Pt, Ag, and Cr.

The first buffer layer may be polyethylene dioxythiophene / polystyrenesulfonic acid (PEDOT / PSS), but is not limited thereto. The second buffer layer may include at least one of BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline), LiF, copper phthalocyanine, polythiophene, polyaniline, But are not limited to, polyacetylene, polypyrrole, polyphenylenevinylene, derivatives thereof, and the like.

The intrinsic layer may be a layer in which a p-type organic material and an n-type organic material are notarized, and the p-type organic material may or may not be the same material as the material forming the p-type organic material layer. The n-type organic material may or may not be the same material as the n-type organic material layer. The intrin layer may be formed by, for example, CuPc as a p-type organic material and C ₆₀ as an n-type organic material, but is not limited thereto.

For example, in the case of a red unit, a first electrode layer made of ITO, a hole transport layer made of PEDOT: PSS, a first P-type organic material layer made of P6T, and a first electrode layer made of BP3T a second electrode layer made of a formed exciton blocking layer, a second P-type organic material layer made of CuPc, CuPc and C ₆₀ a ball the deposited STE Lin sikcheung, N-type made of a C ₆₀ organic material layer, a buffer layer consisting of BCP, and Al &Lt; / RTI > The CdS absorbs the blue light, thereby preventing the sensitivity of the red light and the decrease of the contrast caused by the blue light.

The exemplary light receiving element can be used for various photoelectric conversion elements. In one example, the device may be an imaging device such as, for example, a CCD image sensor or a CMOS image sensor.

The CMOS (Complementary Metal Oxide Semiconductor) image sensor includes a power control unit for controlling power supply; A light receiving unit CMOS that is supplied with power by the power supply control unit and receives light to generate an electrical signal; An output unit CMOS for outputting a signal received from the light receiving unit CMOS; . &Lt; / RTI >

Conventionally, in the case of a pixel used in a light receiving unit, it has been difficult to control the pixel size by arranging pixels of blue, green, and red separately. On the other hand, the exemplary image sensor of the present invention is an organic photoelectric conversion system in which a plurality of color units that simultaneously perform photoelectric conversion and color filter functions are included and include light receiving elements.

Thus, by using a light-receiving element having a multilayer laminate structure which is excellent in color purity, sensitivity and contrast without using a color filter and a photodiode, it is advantageous in downsizing or large-sized. In addition, problems such as sensitivity reduction, false coloring, moiré phenomenon, resolution degradation, and the like, which occur when conventional color filter pixels are used, can be solved.

However, it is not necessary that all of the color units are color units of the type illustrated in the present invention. For example, when a red unit according to an example of the present invention is included, the blue unit or green unit may be a color unit made of a known inorganic semiconductor compound.

In a specific example, (i) an image sensor comprising an exemplary red color unit, a silicon-based green color unit and a silicon-based blue color unit of the present invention, (ii) a color unit for red of the exemplary organic photoelectric conversion system of the present invention, A green color unit, and an image sensor including an exemplary organic photoelectric conversion type blue color unit of the present invention may all be included in the scope of the present invention.

The image sensor can be widely used for a digital camera, a broadcasting camera, a surveillance camera, a computer image camera, a camcorder, an automobile sensor, a home sensor, a computer video call, and an IR sensor. In addition, since the light receiving element has a photoelectric conversion function, it can be effectively used for an organic thin film solar cell.

Hereinafter, the present invention will be described in detail according to an embodiment of the present invention.

[Comparative Example 1]

The ITO glass is washed with water / ultrasonic waves and methanol and acetone, followed by O ₂ plasma treatment. A PEDOT: PSS film is formed to a thickness of 30 nm on the ITO glass by a spin coating method. Then, a CuPc layer, a C ₆₀ layer, and a BCP layer are sequentially deposited at a deposition rate of 1 Å / s at a pressure of 1 × 10 ^-7 torr by thermal evaporation. Thereafter, by depositing an Al electrode of 100 nm thick on the BCP layer at a deposition rate of approximately 5Å / s, ITO / PEDOT: to produce a _{PSS / CuPc / C 60 / BCP} / Al color unit of the stack structure.

[Example 1]

Forming a CdS layer on the ITO on the color unit of Comparative Example 1, CdS / ITO / PEDOT: to produce a _{PSS / CuPc / C 60 / BCP} / Al color unit of the stack structure.

[Experimental Example 1] Incident Photon to Current Efficiency (IPCE) measurement

Monochromatic light was sequentially irradiated to the color units manufactured in Comparative Example 1 and Example 1 in the order of the visible light wavelength in the ITO layer direction and the external quantum efficiency was measured according to the wavelength band. 6 to 7 (Fig. 6: Comparative Example 1, Fig. 7: Example 1). A function generator (Hokudo Denko, Ltd., HB-104) was used, using a monochromatic light with a xenon lamp and a monochromator.

Referring to FIG. 6-7, it can be seen that IPCE at 400 nm to 500 nm hardly occurs in Example 1 in which the light absorbing layer including CdS was formed according to Example 1. It is presumed that the CdS layer absorbs the wavelength of 400 nm to 500 nm. Therefore, it can be seen that the light receiving element according to the first embodiment can prevent the blue wavelength region from being absorbed by the red unit, so that the color sensitivity, purity and contrast ratio of the red unit can be increased.

Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

1 is a sectional view of a light receiving element according to an example of the present invention;

2 is a cross-sectional view of a light receiving element according to another example of the present invention;

3 is a sectional view of a light receiving element according to another example of the present invention;

Figure 4 is a cross-sectional view of a color unit according to an example of the present invention;

5 is a cross-sectional view of a color unit according to another example of the present invention;

6 is a result of an experiment of Comparative Example 1 according to Experimental Example 1;

Fig. 7 shows the experimental results of Example 1 according to Experimental Example 1. Fig.

DESCRIPTION OF THE RELATED ART [0002]

100: Blue unit 200: Green unit

300: red unit 410, 420, 430: absorbing layer

Claims

One or more color units that selectively absorb wavelengths of a specific color and form a PN junction structure; And

A light absorbing layer including a light absorber capable of absorbing light of a desired wavelength is sequentially stacked on the upper or lower portion of the color unit,

The color unit comprises: a first P-type organic material layer made of a light absorbing organic material capable of selectively absorbing a wavelength other than a desired wavelength; An exciton blocking layer capable of blocking exciton migration; A second P-type organic material layer made of a light absorbing organic material capable of absorbing a desired wavelength, and a N-type organic material layer.

The light-receiving element according to claim 1, wherein a blue unit, a green unit, and a red unit are sequentially stacked from the light-receiving surface side.

The light receiving element according to claim 2, wherein the light absorbing layer is formed on a selected portion of an upper portion of the blue unit, between the blue unit and the green unit, between the green unit and the red unit, or an upper portion of the red unit.

The light-receiving element according to claim 1, wherein the light-absorbing layer is composed of a light absorber for selectively absorbing a wavelength other than a specific wavelength absorbed by the color unit formed in a lower portion thereof.

The light-receiving element according to claim 3, wherein the light absorbing layer (the 'light absorbing layer for blue unit') formed on the blue unit is made of a material capable of absorbing light having a longer wavelength than 492 nm.

The light emitting device according to claim 3, wherein the light absorbing layer ('light absorbing layer for green unit') formed on the green unit absorbs light having a shorter wavelength than 492 nm or absorbs light having a wavelength longer than 577 nm Receiving element.

4. The light emitting device according to claim 3, wherein the light absorbing layer (the 'light absorbing layer for a red unit') formed on the red unit absorbs light having a wavelength shorter than 600 nm or absorbs light having a wavelength longer than 800 nm Receiving element.

The light-receiving element according to claim 1, wherein the light-absorbing layer is composed of a light absorbing agent that selectively absorbs a specific wavelength absorbed in a color unit formed on an upper portion thereof.

The light-receiving element according to claim 1, wherein the light absorbing agent is a color material in a complementary color relationship with the color of the color unit formed on the light absorbing layer including the light absorbing layer.

10. The light-receiving element according to claim 9, wherein the color material is any one of coloring materials selected from the group consisting of organic dyes, organic pigments, and inorganic pigments.

The light-receiving element according to claim 2, wherein the light-absorbing layer (first light-absorbing layer) formed in the lower portion of the blue unit is made of a colorant of a yellow-based color having a complementary relation to blue color.

The light-receiving element according to claim 2, wherein the light absorbing layer (second light absorbing layer) formed below the green unit is composed of an orange or magenta color material having a complementary color relation to the green color.

13. The light-receiving element according to claim 12, wherein the color material comprises cadmium sulfide (CdS) or a derivative thereof.

The light receiving element according to claim 1, wherein an insulating layer including an insulating material is formed between the color units, and the light absorbing agent is contained in the insulating layer.

The light-receiving element according to claim 1, wherein the light absorbing layer further comprises an insulating material.

The light-receiving element according to claim 1, wherein each of the color units comprises a P-type organic material layer and an N-type organic material layer made of a light absorbing organic material capable of selectively absorbing only a desired wavelength.

3. The method of claim 2, wherein the blue unit comprises a P-type organic material layer deposited with TPD; And an N-type organic material layer deposited with C ₆₀ ; .

The organic light emitting display according to claim 2, wherein the green unit comprises a P-type organic material layer made of TPD; TPD and Me-PTC co-deposited; And an N-type organic material layer made of NTCDA; .

delete

The organic electroluminescent device according to claim 2, wherein the red unit comprises: a first P-type organic material layer made of P6T; An exciton blocking layer made of BP3T; A second P-type organic material layer made of CuPc; An N-type organic material layer made of C ₆₀ ; .

One or more color units that selectively absorb wavelengths of a specific color and form a PN junction structure; And a light absorbing layer including a light absorber capable of absorbing light of a desired wavelength on the upper or lower portion of the color unit,

Each color unit comprising:

A first electrode layer formed on the P-type organic material layer;

An intrinsic layer formed between the P-type organic material layer and the N-type organic material layer and having a p-type organic material and an n-type organic material adhered to each other;

A second electrode layer formed under the N-type organic material layer; And

A second buffer layer formed between the N-type organic material layer and the second electrode layer; Further comprising a layer made of a transparent conductive material.

The organic electroluminescent device according to claim 21, wherein the color unit comprises a first electrode layer / a first buffer layer / a p-type organic material layer / a first phosphor layer / an n-type organic material layer / a second buffer layer / And the light absorbing layer is formed on an upper portion of the first electrode layer or a lower portion of the second electrode layer.

An imaging device comprising a light-receiving element according to any one of claims 1 to 18, and 20 to 22.

delete