WO2025088750A1 - Light-emitting element, display device, and method for manufacturing light-emitting element - Google Patents

Abstract

A light-emitting element (10) according to an example of the present disclosure comprises: a first electrode (11); a second electrode (12) including a non-translucent conductive material with a light-transmissive thickness; and a functional layer (13) positioned between the first electrode (11) and the second electrode (12). The second electrode (12) includes a first portion (P1) and a second portion (P2) having a larger thickness than that of the first portion (P1). The functional layer (13) includes a thin film portion (Q1) positioned between the first electrode (11) and the first portion (P1), and a thick film portion (Q2) positioned between the first electrode (11) and the second portion (P2) and having a larger thickness than that of the thin film portion (Q1).

Description

Light emitting device, display device, and method for manufacturing light emitting device

This disclosure relates to a light-emitting device, a display device, and a method for manufacturing a light-emitting device.

Patent Document 1 discloses an organic EL display device that uses a microcavity structure to improve light extraction efficiency.

JP 2011-171094 A

In light-emitting devices with a microcavity structure, unevenness in the thickness of the functional layer between the electrodes reduces the light extraction efficiency.

A light-emitting element according to one embodiment of the present disclosure includes a first electrode, a second electrode including a non-transparent conductive material having a thickness that allows light to pass through, and a functional layer including a light-emitting layer located between the first electrode and the second electrode, the second electrode including a first portion and a second portion having a thickness greater than that of the first portion, and the functional layer including a thin film portion located between the first electrode and the first portion, and a thick film portion located between the first electrode and the second portion having a thickness greater than that of the thin film portion.

A light-emitting element according to one embodiment of the present disclosure includes a first electrode, a second electrode that includes a translucent conductive material and is light-transmitting, and a functional layer that is located between the first electrode and the second electrode and includes a light-emitting layer, the second electrode includes a first portion and a second portion that is thicker than the first portion, and the functional layer includes a thin film portion that is located between the first electrode and the second portion, and a thick film portion that is located between the first electrode and the first portion and is thicker than the thin film portion.

The display device according to one embodiment of the present disclosure is configured to include red light-emitting elements, green light-emitting elements, and blue light-emitting elements, each of which is a light-emitting element according to one embodiment of the present disclosure.

The method for manufacturing a light-emitting element according to one embodiment of the present disclosure is a method for manufacturing a light-emitting element having a first electrode, a second electrode, and a functional layer including a light-emitting layer, located between the first electrode and the second electrode, and includes the steps of forming the functional layer having a thin film portion and a thick film portion having a thickness greater than that of the thin film portion, and forming the second electrode having a first portion and a second portion having a thickness greater than that of the first portion, and in the step of forming the second electrode, the first portion and the second portion are formed by performing a deposition process multiple times.

According to one aspect of the present disclosure, the light extraction efficiency is improved.

1 is a cross-sectional view illustrating a configuration example of a light-emitting device according to an embodiment of the present disclosure. 2 is a cross-sectional view showing an example of a functional layer shown in FIG. 1 . 1A to 1C are cross-sectional views illustrating an example of a method for manufacturing a light-emitting device according to an embodiment of the present disclosure. 5A to 5C are cross-sectional views showing an example of a step of forming a second electrode. 5A to 5C are cross-sectional views showing an example of a step of forming a second electrode. 5A to 5C are cross-sectional views showing an example of a step of forming a second electrode. 5A to 5C are cross-sectional views showing an example of a step of forming a second electrode. 1 is a cross-sectional view showing a modified example of the configuration of a light-emitting element according to an embodiment of the present disclosure. 1 is a cross-sectional view illustrating a configuration example of a light-emitting device according to an embodiment of the present disclosure. 10 is a cross-sectional view showing a modified example of the configuration of a light-emitting element according to an embodiment of the present disclosure. FIG. 1 is a plan view illustrating a configuration example of a display device according to an embodiment of the present disclosure. 1 is a cross-sectional view illustrating a configuration example of a display device according to an embodiment of the present disclosure. FIG. 11 is a plan view showing a modified example of the configuration of a display device according to an embodiment of the present disclosure. 13 is a graph showing the relationship between the thickness of the second electrode and the luminance front extraction efficiency in a red light emitting element. 13 is a graph showing the relationship between the thickness of the second electrode and the luminance front extraction efficiency in a green light emitting element.

[Embodiment 1]
(composition)
Fig. 1 is a cross-sectional view showing a configuration example of a light-emitting element according to an embodiment of the present disclosure. As shown in Fig. 1, the light-emitting element 10 according to the present disclosure includes a first electrode 11, a second electrode 12 including a non-translucent conductive material having a thickness that allows light to pass through, and a functional layer 13 located between the first electrode 11 and the second electrode 12. The second electrode 12 includes a first portion P1 and a second portion P2 having a thickness greater than that of the first portion P1. The functional layer 13 includes a thin film portion Q1 located between the first electrode 11 and the first portion P1, and a thick film portion Q2 located between the first electrode 11 and the second portion P2 and having a thickness greater than that of the thin film portion Q1.

The light-emitting element 10 may be formed on a support substrate BP, and a circuit layer CL may be formed between the support substrate BP and the light-emitting element 10. The light-emitting element 10 may further include a transparent layer 14 located between the first electrode 11 and the functional layer 13. The light-emitting element 10 may further include an edge cover 15 that covers the edge of the first electrode 11 or the second electrode 12.

2 is a cross-sectional view showing an example of the functional layer shown in FIG. 1. As shown in FIG. 2, the functional layer 13 may include an emitting layer EML. In the emitting layer EML, a portion EM1 located in the thin film portion Q1 has a smaller thickness than a portion EM2 located in the thick film portion Q2. The emitting layer EML may include luminescent quantum dots or may include a luminescent organic material. The quantum dots may emit light, for example, by electroluminescence. The functional layer 13 may additionally include one or more of a hole injection layer, a hole transport layer HTL, an electron blocking layer, a hole blocking layer, an electron transport layer ETL, and an electron injection layer. The additional layers may have a substantially constant thickness, or the portion located in the thin film portion Q1 may have a smaller thickness than the portion located in the thick film portion Q2.

In the functional layer 13, the thin film portion Q1 may be located outside the thick film portion Q2. The thin film portion Q1 may be a peripheral portion of the functional layer 13. In a plan view, the first portion P1 and the second portion P2 may be located within the light-emitting region where the light-emitting layer EML emits light.

The non-transparent conductive material contained in the second electrode 12 has a front reflectance of 50% or more in the bulk. The front reflectance in the bulk is the reflectance when visible light is incident from a vacuum onto the bulk of the material in the normal direction to the incident surface. The non-transparent conductive material may be a metal material, and may have an extinction coefficient of 1 or more at the peak wavelength of the emitting layer EML. The metal material may include one or more selected from aluminum, magnesium, silver, chromium, nickel, copper, tungsten, platinum, tin, gold, and silver.

The first electrode 11 may be a light-reflecting electrode. The second electrode 12 may be located above the first electrode 11, and an optical resonator that reinforces light in a specific wavelength range may be formed between the upper surface of the first electrode 11 and the lower surface of the second electrode 12. Alternatively, a light-reflecting layer may be provided separately from the first electrode 11. The second electrode 12 may be located above the light-reflecting layer, and an optical resonator that reinforces light in a specific wavelength range may be formed between the upper surface of the light-reflecting layer and the lower surface of the second electrode 12. The specific wavelength range may be, for example, the peak wavelength of the light-emitting layer EML and a wavelength range of ±10 nm therebetween. The optical resonator may be formed anywhere in the light-emitting region of the functional layer 13, and may be formed in either the thin film portion Q1 or the thick film portion Q2.

In this disclosure, "upper" refers to the direction in which the functional layer 13 is located relative to the support substrate BP, and "lower" refers to the direction in which the support substrate BP is located relative to the functional layer 13. In the example shown in FIG. 1, the light-emitting element 10 is a top-emission type.

When reflected from the second electrode 12, a phase difference occurs between the incident light and the reflected light. The non-transparent conductive material contained in the second electrode 12 may have a so-called "fixed end reflection" in its bulk. Reflection in the bulk is the reflection that occurs when visible light is incident from a vacuum into the bulk of the material in the normal direction to the incident surface. Since the thickness of the second electrode 12 is small enough to allow light to pass through, the phase difference due to reflection depends on the thickness of the reflected portion of the second electrode 12. The thicker the second electrode 12, the greater the phase difference.

In order to form an optical resonator, it is preferable that the following conditions are satisfied:
2L/λ+Φ/2π=m...(1)
L is the optical distance between the first electrode 11 and the second electrode 12, λ is the peak wavelength of the emission spectrum of the emitting layer EML, Φ is the phase shift (rad) due to reflection at the second electrode 12, and m is an integer. The optical distance L is the product of the refractive index n and the thickness d between the first electrode 11 and the second electrode 12.

In the functional layer 13 located between the first electrode 11 and the second electrode 12, the thin film portion Q1 and the thick film portion Q2 have different thicknesses. For this reason, for example, if a design is made so that an optical resonator is formed in the portion including the thin film portion Q1, the conditions for the optical resonator will be deviated from those in the portion including the thick film portion Q2, and the light extraction efficiency will decrease in the thick film portion Q2, resulting in a decrease in the light extraction efficiency of the light-emitting element.

Furthermore, if the difference between the optical path length LA1 of the thin film portion Q1 and the optical path length LA2 of the thick film portion Q2 is 5% or more of the optical path length LA1, or if the difference between the thickness of the thin film portion Q1 and the thickness of the thick film portion Q2 is 5% or more of the thickness of the thin film portion Q1, uneven brightness and color within the pixel will become noticeable. In particular, if the difference in the peak wavelength within the pixel of the light emitted from the light emitting element 10 exceeds 10 nm, uneven color will become noticeable. Therefore, it is preferable that the difference between the maximum peak wavelength and the minimum peak wavelength within one light emitting element be 10 nm or less.

In the light-emitting element 10, the second portion P2 of the second electrode 12 is formed to correspond to the thick film portion Q2, thereby making it possible to suppress at least one of brightness unevenness and color unevenness within the pixel. In particular, it is preferable to suppress the distribution of peak wavelengths within the pixel to 10 nm or less by adjusting the film thickness of the second portion P2. It is also preferable to suppress the front brightness unevenness within the pixel to 20% or less by adjusting the film thickness of the second portion P2.

The phase shift Φ due to reflection at the second electrode 12 can be approximated by the following equation (2).
tanΦ=(2×nf×k)/(nf ² -ns ² +k ² )...(2)
Here, the refractive index of the second electrode 12 is ns, the extinction coefficient of the second electrode 12 is k, and the refractive index of the portion of the functional layer 13 adjacent to the second electrode 12 is nf. When the second electrode 12 is silver, in the wavelength range of visible light, the refractive index ns is smaller than 1, and the extinction coefficient k is 1 or more and increases as the wavelength becomes longer. Therefore, the phase shift Φ increases in the order of red pixel, green pixel, and blue pixel. Therefore, in a display device having red pixels, green pixels, and blue pixels as described later, when the difference between the optical path length LA1 in the thin film portion Q1 and the optical path length LA2 in the thick film portion Q2 of each pixel, or the difference between the thickness of the thin film portion Q1 and the thickness of the thick film portion Q2 of each pixel is approximately the same, the thickness of the second portion P2 of the second electrode 12 may be formed so that it decreases in the order of red pixel, green pixel, and blue pixel.

Furthermore, it is preferable that the thickness of the second portion P2 of the second electrode 12 is formed to be 1000 nm or less, and more preferably 500 nm or less. This is because the transmittance of the second electrode 12, which contains a non-transparent conductive material, drops significantly as the thickness increases.

(Production method)
Fig. 3 is a cross-sectional view showing an example of a method for manufacturing a light-emitting element according to an embodiment of the present disclosure. Fig. 3 shows a method for manufacturing a light-emitting element 10 including a first electrode 11, a second electrode 12, and a functional layer 13 located between the first electrode 11 and the second electrode 12. As shown in Fig. 3, in the example of the manufacturing method, a support substrate BP is first prepared, and a circuit layer CL, a first electrode 11, an edge cover 15 that covers the edge of the first electrode 11, and a transparent layer 14 are formed in this order on the support substrate BP.

Subsequently, a functional layer 13 having a thin film portion Q1 and a thick film portion Q2 having a thickness greater than that of the thin film portion Q1 is formed on the transparent layer 14 (step S10). The process of forming the functional layer 13 may include a process of forming one or more of a hole injection layer, a hole transport layer HTL, and an electron blocking layer (step S12). The process of forming the functional layer 13 may include a process of drying a coating liquid of the quantum dot dispersion liquid to form an emission layer EML (step S14). The process of forming the functional layer 13 may include a process of forming one or more of a hole blocking layer, an electron transport layer ETL, and an electron injection layer (step S16).

Next, a second electrode 12 having a first portion P1 and a second portion P2 having a thickness greater than that of the first portion P1 is formed on the functional layer 13 (step S20). In the process of forming the second electrode 12, the first portion P1 and the second portion P2 can be formed by performing a deposition process multiple times.

FIG. 4 is a cross-sectional view showing an example of a process for forming a second electrode. As shown in FIG. 4, in the process for forming the second electrode 12, a first evaporated film F1 can be formed in a planar shape (step S22), and then a second evaporated film F2 can be patterned (step S24). The first evaporated film F1 and the second evaporated film F2 constitute the second electrode 12.

FIG. 5 is a cross-sectional view showing another example of the process of forming the second electrode. As shown in FIG. 5, in the process of forming the second electrode 12, the first vapor-deposited film F1 can be patterned (step S122), and then the second vapor-deposited film F2 can be formed in a planar shape (step S124).

FIG. 6 is a cross-sectional view showing another example of the process of forming the second electrode. As shown in FIG. 6, in the process of forming the second electrode 12, the first deposited film F1 is patterned (step S122), and then the second deposited film F2 is patterned (step S126) so as to overlap a part of the first deposited film F1 and the opening A1 of the first deposited film F1. The first deposited film F1 also overlaps a part of the second deposited film F2 and the opening A2 of the second deposited film F2. In this case, it is beneficial that the patterns of the first deposited film F1 and the second deposited film F2 are the same in a plan view, but are different in position. The first deposited film F1 and the second deposited film F2 may have the same thickness.

FIG. 7 is a cross-sectional view showing another example of the process of forming the second electrode. As shown in FIG. 7, in the process of forming the second electrode 12, the first deposited film F1 is patterned (step S122), and then a second deposited film F2 having a thickness different from that of the first deposited film F1 is patterned (step S128) so as to overlap the opening A1 of the first deposited film F1. In addition, the first deposited film F1 overlaps the opening A2 of the second deposited film F2. In this case, the patterns of the first deposited film F1 and the second deposited film F2 may be complementary in a planar view.

(Modification)
Fig. 8 is a cross-sectional view showing a modified example of the configuration of the light-emitting element according to an embodiment of the present disclosure. As shown in Fig. 8, the second electrode 12 is located in a lower layer than the first electrode 11, and an optical resonator that reinforces light in a specific wavelength range may be formed between the lower surface of the first electrode 11 and the upper surface of the second electrode 12. In the example shown in Fig. 8, the light-emitting element 10 is a bottom emission type.

[Embodiment 2]
Other embodiments of the present disclosure will be described below. For convenience of explanation, the same reference numerals will be given to members having the same functions as those described in the above embodiment, and the description thereof will not be repeated.

(composition)
9 is a cross-sectional view showing a configuration example of a light-emitting element according to an embodiment of the present disclosure. As shown in FIG. 9, the light-emitting element 20 according to the present disclosure includes a first electrode 11, a second electrode 22 containing a transparent conductive material and capable of transmitting light, and a functional layer 13 located between the first electrode 11 and the second electrode 22, the second electrode 22 including a first portion P3 and a second portion P4 having a thickness greater than that of the first portion P3, and the functional layer 13 including a thin film portion Q1 located between the first electrode 11 and the first portion P3, and a thick film portion Q2 located between the first electrode 11 and the second portion P4 and having a thickness greater than that of the thin film portion Q1.

The light-emitting element 20 may be formed on a support substrate BP, and a circuit layer CL may be formed between the support substrate BP and the light-emitting element 20. The light-emitting element 20 may further include a transparent layer 14 located between the first electrode 11 and the functional layer 13.

The functional layer 13 includes an emitting layer EML, and the emitting layer EML has a portion EM1 located in the thin film portion Q1 that is thinner than a portion EM2 located in the thick film portion Q2. The emitting layer EML may include luminescent quantum dots, or may include a luminescent organic material. The functional layer 13 may further include one or more of a hole injection layer, a hole transport layer HTL, an electron blocking layer, a hole blocking layer, an electron transport layer ETL, and an electron injection layer.

In the functional layer 13, the thin film portion Q1 may be located outside the thick film portion Q2. The thin film portion Q1 may be a peripheral portion of the functional layer 13. In a plan view, the first portion P3 and the second portion P4 may be located within the light-emitting region where the light-emitting layer EML emits light.

The translucent conductive material contained in the second electrode 22 has a visible light transmittance of 50% or more. The translucent conductive material may be a metal oxide material and may have an extinction coefficient of less than 1 at the peak wavelength of the light-emitting layer EML. The translucent conductive material may include one or more selected from the group including indium tin oxide, indium zinc oxide, zinc oxide, titanium oxide, graphene, silver nanowires, carbon nanotubes, and polyethylenedioxythiophene.

The first electrode 11 may be a light-reflecting electrode. The second electrode 22 may be located in a layer above the first electrode 11, and an optical resonator that reinforces light of a specific wavelength range may be formed between the upper surface of the second electrode 22 and the upper surface of the second electrode 12. Alternatively, a light-reflecting layer may be provided separately from the first electrode 11. The second electrode 22 may be located in a layer above the light-reflecting layer, and an optical resonator that reinforces light of a specific wavelength range may be formed between the upper surface of the light-reflecting layer and the upper surface of the second electrode 12. In the example shown in FIG. 9, the light-emitting element 20 is a top-emission type.

No phase difference occurs between the incident light and the reflected light when reflected from the second electrode 22. The light-transmitting conductive material contained in the second electrode 22 may have a so-called "free-end reflection" in its bulk. Reflection in the bulk is the reflection that occurs when visible light is incident from a vacuum into the bulk of the material in the normal direction to the plane of incidence.

According to the configuration of this embodiment, the second electrode 22 includes the first portion P3 and the second portion P4 having a thickness greater than that of the first portion P3. In the light-emitting element 20, the third portion P3 of the second electrode 22 is formed to correspond to the thick portion Q2, and the second portion P4 of the second electrode 22 is formed to correspond to the thin portion Q1, so that the phase shift Φ differs between the thin portion Q1 and the thick portion Q2. As a result of at least partially offsetting the difference in optical distance by the difference in phase shift Φ, at least one of the brightness unevenness and color unevenness in the pixel can be reduced. Therefore, the difference between the thickness of the thin portion Q1 and the thickness of the thick portion Q2 may be 5% or more with respect to the thickness of the thin portion Q1. In particular, it is preferable to reduce the difference between the maximum peak wavelength and the minimum peak wavelength of the multiple peak wavelengths obtained by spatially resolving the peak wavelength of the emitted light in the pixel to 10 nm or less by adjusting the film thickness of the second portion P4. It is also preferable to reduce the front brightness unevenness in the pixel to 20% or less by adjusting the film thickness of the second portion P4. The upper surface of the second electrode 22 is formed to be flat, for example.

(Production method)
The method of manufacturing the light emitting device 20 according to the second embodiment and the process of forming the second electrode 22 will be clear to those skilled in the art with reference to the first embodiment described above, and therefore the description thereof will not be repeated.

(Modification)
Fig. 10 is a cross-sectional view showing a modified example of the configuration of the light-emitting element according to an embodiment of the present disclosure. As shown in Fig. 10, the second electrode 22 is located in a lower layer than the first electrode 11, and an optical resonator that reinforces light of a specific wavelength range may be formed between the lower surface of the first electrode 11 and the lower surface of the second electrode 12. In the example shown in Fig. 10, the light-emitting element 20 is a bottom emission type.

[Embodiment 3]
Fig. 11 is a plan view showing a configuration example of a display device according to an embodiment of the present disclosure. As shown in Fig. 11, the display device 100 according to the present disclosure includes a display section DA in which a plurality of pixels PX are provided, and a drive circuit DC for driving the display section DA. The pixels PX include a red pixel PR including a red light emitting element 30 and a pixel circuit 39, a green pixel PG including a green light emitting element 40 and a pixel circuit 49, and a blue pixel PB including a blue light emitting element 50 and a pixel circuit 59.

FIG. 12 is a cross-sectional view showing an example of the configuration of a display device according to an embodiment of the present disclosure. As shown in FIG. 12, the display device 100 according to the present disclosure includes a red light-emitting element 30, a green light-emitting element 40, and a blue light-emitting element 50, and each of the red light-emitting element 30, the green light-emitting element 40, and the blue light-emitting element 50 is the light-emitting element 10 according to the above-mentioned embodiment 1.

The thickness of the first portion P1 of the second electrode 12 may be different in the red light-emitting element 30, the green light-emitting element 40, and the blue light-emitting element 50. Additionally or alternatively, the thickness of the second portion P2 of the second electrode 12 may be different. The second portions P2 may be formed such that the thickness of each second portion P2 decreases in the order of the red light-emitting element 30, the green light-emitting element 40, and the blue light-emitting element 50. The thickness of the thin film portion Q1 of the functional layer 13 may be different in the red light-emitting element 30, the green light-emitting element 40, and the blue light-emitting element 50. Additionally or alternatively, the thickness of the thick film portion Q2 of the functional layer 13 may be different.

The red light-emitting element 30, the green light-emitting element 40, and the blue light-emitting element 50 may each further include a transparent layer 14 located between the first electrode 11 and the functional layer 13. The thickness of the transparent layer 14 may be different from each other in the red light-emitting element 30, the green light-emitting element 40, and the blue light-emitting element 50. The transparent layer 14 may be conductive or have charge transport properties.

(Modification)
13 is a plan view showing a modified example of the configuration of the display device according to the embodiment of the present disclosure. As shown in Fig. 13, each of the red light emitting element 30, the green light emitting element 40, and the blue light emitting element 50 may be the light emitting element 20 according to the second embodiment described above.

The thicknesses of the first portion P3 of the second electrode 22 may be different from each other in the red light-emitting element 30, the green light-emitting element 40, and the blue light-emitting element 50. Additionally or alternatively, the thicknesses of the second portion P4 of the second electrode 22 may be different from each other.

(Example)
Fig. 14 shows a graph showing the relationship between the thickness of the second electrode in a red light-emitting element and the luminance front extraction efficiency. Fig. 15 shows a graph showing the relationship between the thickness of the second electrode in a green light-emitting element and the luminance front extraction efficiency. These graphs are based on the results of optical calculations performed by the inventors when the red light-emitting element 30 and the green light-emitting element 40 are the light-emitting element 10 according to the above-mentioned embodiment 1. In Figs. 14 and 15, the horizontal axis "upper electrode thickness" indicates the thickness of the second electrode 12, and the thicknesses added to each locus indicate the thickness of the functional layer 13.

As shown in Figures 14 and 15, the suitable thickness of the second electrode 12 varies depending on the thickness of the functional layer 13. By varying the thickness of the second electrode 12 according to the uneven thickness of the functional layer 13, the light extraction efficiency of the light-emitting element 10 can be improved.

This disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. The technical scope of this disclosure also includes embodiments obtained by appropriately combining the technical means disclosed in different embodiments. Furthermore, new technical features can be formed by combining the technical means disclosed in each embodiment.

10, 20 Light emitting element 11 First electrode 12, 22 Second electrode 13 Functional layer 14 Transparent layer 15 Edge cover A1, A2 Opening DA Display section DC Drive circuit EML Light emitting layer EM1, EM2 Part F1 First evaporated film F2 Second evaporated film P1 First section P2 Second section Q1 Thin film section Q2 Thick film section

Claims (34)

A first electrode;
a second electrode including a non-light-transmitting conductive material having a thickness allowing light to pass therethrough;
a functional layer including a light-emitting layer, the functional layer being located between the first electrode and the second electrode;
the second electrode includes a first portion and a second portion having a thickness greater than that of the first portion;
A light-emitting element, wherein the functional layer includes a thin film portion located between the first electrode and the first portion, and a thick film portion located between the first electrode and the second portion and having a thickness greater than that of the thin film portion. The light-emitting element according to claim 1, wherein the portion of the light-emitting layer located in the thin film portion has a smaller thickness than the portion located in the thick film portion. The light-emitting element according to claim 2, wherein the light-emitting layer contains light-emitting quantum dots. The light-emitting element according to any one of claims 1 to 3, wherein the thin film portion is located outside the thick film portion in the functional layer. The light-emitting element according to any one of claims 1 to 4, wherein the non-transparent conductive material is a metal material. The light-emitting element according to any one of claims 1 to 5, wherein the non-transparent conductive material has an extinction coefficient of 1 or more at the peak wavelength of the light-emitting layer. The light-emitting device according to any one of claims 1 to 6, wherein the first electrode is a light-reflecting electrode. The light-emitting element of claim 7, wherein the metal material includes one or more selected from aluminum, magnesium, silver, chromium, nickel, copper, tungsten, platinum, tin, gold, and silver. The second electrode is located in a layer above the first electrode,
The light-emitting element according to any one of claims 1 to 8, wherein an optical resonator is formed between an upper surface of the first electrode and a lower surface of the second electrode, which reinforces light within a range of ±10 nm of a peak wavelength of the light-emitting layer. The light-emitting element according to any one of claims 1 to 9, wherein the first portion and the second portion are located within a light-emitting region in a plan view. The light-emitting device according to claim 4, wherein the thin film portion is a peripheral portion of the functional layer. A first electrode;
a second electrode including a transparent conductive material and capable of transmitting light;
a functional layer including a light-emitting layer, the functional layer being located between the first electrode and the second electrode;
the second electrode includes a first portion and a second portion having a thickness greater than that of the first portion;
A light-emitting element, wherein the functional layer includes a thin film portion located between the first electrode and the second portion, and a thick film portion located between the first electrode and the first portion and having a thickness greater than that of the thin film portion. The functional layer includes a light-emitting layer,
The light-emitting element according to claim 12 , wherein the light-emitting layer has a thickness smaller in a portion located in the thin film portion than in a portion located in the thick film portion. The light-emitting element according to claim 13, wherein the light-emitting layer contains light-emitting quantum dots. The light-emitting element according to any one of claims 12 to 14, wherein the thin film portion is located outside the thick film portion in the functional layer. The light-emitting element according to any one of claims 12 to 15, wherein the transparent conductive material is a metal oxide material. The light-emitting device according to any one of claims 12 to 16, wherein the translucent conductive material has an extinction coefficient of less than 1 at the peak wavelength of the light-emitting layer. The light-emitting element according to any one of claims 12 to 17, wherein the transparent conductive material includes one or more selected from the group including indium tin oxide, indium zinc oxide, zinc oxide, titanium oxide, graphene, silver nanowires, carbon nanotubes, and polyethylenedioxythiophene. The second electrode is located in a layer above the first electrode,
The light-emitting element according to any one of claims 12 to 18, wherein an optical resonator is formed between an upper surface of the first electrode and an upper surface of the second electrode, which reinforces light in a wavelength range of ±10 nm of a peak wavelength of the light-emitting layer. The light-emitting device according to any one of claims 12 to 19, in which no phase difference occurs in the light reflection at the second electrode. The light-emitting element according to any one of claims 1 to 20, wherein the difference between the thickness of the thin film portion and the thickness of the thick film portion is 5% or more of the thickness of the thin film portion. The light-emitting device according to claim 21, in which the difference between the maximum and minimum peak wavelengths among multiple peak wavelengths obtained by spatially resolving the peak wavelengths of the emitted light is 10 nm or less. The light-emitting element according to claim 21 or 22, in which the unevenness in the front brightness of the emitted light within the light-emitting region is 20% or less. A red light emitting element, a green light emitting element and a blue light emitting element are provided,
A display device, wherein each of the red light emitting element, the green light emitting element and the blue light emitting element is the light emitting element according to any one of claims 1 to 23. The display device of claim 24, wherein the thicknesses of the second portions of the red light-emitting element, the green light-emitting element, and the blue light-emitting element are different from each other. a thickness of the second portion of the red light emitting element is smaller than a thickness of the second portion of the green light emitting element;
26. The display of claim 25, wherein a thickness of the second portion of the green light-emitting element is less than a thickness of the second portion of the blue light-emitting element. The display device according to any one of claims 24 to 26, wherein the red light-emitting element, the green light-emitting element, and the blue light-emitting element have different thicknesses of the thick film portions. each of the red light emitting element, the green light emitting element and the blue light emitting element further includes a transparent layer located between the first electrode and the functional layer;
28. The display device according to claim 24, wherein the transparent layer has a thickness different from one another in the red light emitting element, the green light emitting element, and the blue light emitting element. The display device according to claim 28, wherein the transparent layer is conductive or has charge transport properties. A method for manufacturing a light-emitting device comprising: a first electrode, a second electrode; and a functional layer including a light-emitting layer and located between the first electrode and the second electrode, the method comprising the steps of:
forming the functional layer having a thin film portion and a thick film portion having a thickness greater than that of the thin film portion;
forming the second electrode having a first portion and a second portion having a thickness greater than that of the first portion;
The method for manufacturing a light-emitting element, wherein in the step of forming the second electrode, the first portion and the second portion are formed by performing a vapor deposition step multiple times. The method for manufacturing a light-emitting element according to claim 30, wherein in the step of forming the second electrode, the first vapor-deposited film is formed in a planar shape and then the second vapor-deposited film is patterned, or the first vapor-deposited film is patterned and then the second vapor-deposited film is formed in a planar shape. The method for manufacturing a light-emitting element according to claim 30, wherein in the step of forming the second electrode, after patterning the first vapor deposition film, the second vapor deposition film is patterned so as to overlap a portion of the first vapor deposition film and the opening of the first vapor deposition film. The method for manufacturing a light-emitting element according to claim 30, wherein in the step of forming the second electrode, after patterning the first vapor deposition film, a second vapor deposition film having a thickness different from that of the first vapor deposition film is patterned so as to overlap the opening of the first vapor deposition film. The method for manufacturing a light-emitting element according to any one of claims 30 to 33, wherein the step of forming the functional layer includes a step of drying a coating liquid of the quantum dot dispersion liquid to form a light-emitting layer.

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