Display device and manufacturing method thereof

Abstract

The invention relates to a display device and a manufacturing method thereof. There is provided a display device including: a substrate including a plurality of sub-pixels; transparent layers provided in the plurality of sub-pixels, respectively; a first protective layer disposed on the transparent layer; and a second protective layer disposed on the first protective layer. The sub-pixel includes a light-emitting region in which the transparent layer is exposed through the first protective layer and the second protective layer, and a non-light-emitting region around the light-emitting region.

Description

Technical Field

[0001] The present disclosure relates to a display device. Background Art

[0002] With the development of the information society, various demands on display devices for displaying images are increasing. Various types of display devices (eg, liquid crystal displays, organic light emitting diode displays, etc.) are being used.

[0003] Organic light-emitting diodes (OLEDs), among other display devices, emit their own light. Compared to liquid crystal displays (LCDs), OLEDs offer wider viewing angles, superior contrast, and require no separate backlight, making them lighter and thinner, which is beneficial in terms of power consumption. OLEDs can also be driven by low DC voltages, have fast response times, and are relatively low in manufacturing cost.

[0004] Recently, there has been an increasing demand for display devices that use such organic light emitting display devices and require augmented reality (AR), virtual reality (VR), or ultra-high resolution equivalent thereto.

[0005] On the other hand, the common light emitting layer of the organic light emitting display device includes a conductive charge generation layer. If the charge generation layer is integrally formed in the red sub-pixel, the green sub-pixel, and the blue sub-pixel, color mixing may occur between the sub-pixels. Summary of the Invention

[0006] Some implementations of the disclosed technology provide a display device including a transparent layer with improved transmittance.

[0007] Some implementations of the disclosed technology provide display apparatuses including organic light emitting devices with improved efficiency.

[0008] Some implementations of the disclosed technology provide a display device that prevents a transparent layer from being oxidized.

[0009] Some implementations of the disclosed technology provide a method for manufacturing a display device capable of protecting a transparent layer.

[0010] One embodiment provides a display device including: a substrate including a plurality of sub-pixels; a transparent layer disposed in each of the plurality of sub-pixels; a first protective layer disposed on the transparent layer; and a second protective layer disposed on the first protective layer. The sub-pixels include a light-emitting region exposed by the transparent layer through the first and second protective layers, and a non-light-emitting region surrounding the light-emitting region.

[0011] Another embodiment is a method for manufacturing a display device, the method comprising the following steps: forming a transparent layer on a substrate, the substrate including sub-pixels, the sub-pixels having a light-emitting area and a non-light-emitting area around the light-emitting area; forming a first protective layer on the transparent layer; performing a first etching on the transparent layer and the first protective layer; forming a second protective layer on the first protective layer that has been etched by the first etching; performing a second etching on the second protective layer on the light-emitting area; and performing a third etching on the first protective layer on the light-emitting area.

[0012] Additional details of these implementations are included in the detailed description and accompanying drawings.

[0013] According to an embodiment, in the manufacture of a display device, after a first protective layer is deposited on the entire surface of a transparent layer deposited on the entire surface, the transparent layer and the first protective layer may be separated (first etching) for each sub-pixel. The first etching is performed by using a first photoresist as a mask. After the first etching is completed, the first photoresist is removed by an ashing process. The ashing process uses an oxygen plasma process. The transparent layer is manufactured to have a very small thickness in order to increase light transmittance. If the thin transparent layer is exposed to oxygen plasma, it may oxidize. However, in the case of a display device according to an embodiment, during the process of removing the first photoresist, since the first protective layer is provided on the transparent layer, oxidation of the transparent layer can be prevented in advance.

[0014] According to embodiments, during the manufacture of a display device, after the first etching and removal of the first photoresist, a second protective layer may be deposited on the transparent layer to form a light-emitting region and a non-light-emitting region exposing the transparent layer in each sub-pixel. The light-emitting region is formed by performing a second etching on the second protective layer. However, during the second etching process on the second protective layer, the transparent layer may be partially etched by the etching gas, resulting in thickness differences between different portions. However, in a display device according to embodiments, even during the second etching process on the second protective layer, the first protective layer is formed between the transparent layer and the second protective layer, thereby preventing the transparent layer from being partially etched by the etching gas.

[0015] According to an embodiment, during the process of performing the second etching on the second protective layer, the etching rate of the second protective layer to the etching gas is three times or more than the etching rate of the first protective layer to the etching gas and the etching rate of the transparent layer to the etching gas, respectively, thereby allowing the second protective layer to be selectively etched.

[0016] According to an embodiment, a second etching of the second protective layer is performed using a second photoresist as a mask. After the second etching is completed, the second photoresist is removed by an ashing process. The ashing process uses an oxygen plasma process. The transparent layer is manufactured to have a very small thickness to increase light transmittance. If the thin transparent layer is exposed to oxygen plasma, it may oxidize. However, in the case of a display device according to an embodiment, during the process of removing the second photoresist, since the first protective layer is provided on the transparent layer, oxidation of the transparent layer can be prevented in advance.

[0017] According to an embodiment, after removing the second photoresist, a third etching process is performed to remove the first protective layer on the light-emitting region. During the third etching process, the etching rate of the first protective layer to the etchant is five times or more than the etching rate of the second protective layer to the etchant and the etching rate of the transparent layer to the etchant, respectively, thereby allowing the first protective layer to be selectively etched.

[0018] However, the advantageous effects according to the present disclosure are not limited to the above description. In addition, those skilled in the art to which the present disclosure pertains can clearly understand other unmentioned effects from the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a plan view of a display device based on some implementations of the disclosed technology.

[0020] Figure 2 It is along Figure 1 A cross-sectional view taken along line AA'.

[0021] Figure 3 Yes Figure 2 A cross-sectional view of the organic light-emitting device shown.

[0022] Figure 4 As Figure 2 A cross-sectional view of an organic light-emitting device showing a modified example of the organic light-emitting device is shown.

[0023] Figure 5 yes Figure 2 An enlarged view of region Q1.

[0024] Figures 6 to 15 1 is a cross-sectional view of various process steps of a method for manufacturing a display device based on some implementations of the disclosed technology.

[0025] Figure 16 is a cross-sectional view of a display device based on some implementations of the disclosed technology.

[0026] Figure 17 is a cross-sectional view of a display device based on some implementations of the disclosed technology.

[0027] Figure 18 is a cross-sectional view of a display device based on some implementations of the disclosed technology.

[0028] Figure 19 is a cross-sectional view of a display device based on some implementations of the disclosed technology.

[0029] Figure 20 is a cross-sectional view of a display device based on some implementations of the disclosed technology.

[0030] Figure 21 is a cross-sectional view of a display device based on some implementations of the disclosed technology.

[0031] Figure 22 is a cross-sectional view of a display device based on some implementations of the disclosed technology. DETAILED DESCRIPTION

[0032] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0033] The same reference numerals correspond to the same components. In addition, in the drawings, the thickness, ratio and size of the components are exaggerated in order to effectively describe the technical details. The term "and / or" includes all of one or more combinations that can be defined by the relevant configurations.

[0034] Although terms such as first and second can be used to describe various components, the components are not limited by the above terms. The terms are only used to distinguish between one component and other components. For example, without departing from the scope of the rights of various embodiments, a first component can be designated as a second component. Similarly, a second component can be designated as a first component. Unless the context clearly mentions otherwise, expressions in the singular include expressions in the plural.

[0035] Terms such as "under," "lower," "over," and "upper" are used to describe the relationship between components shown in the drawings. These terms have relative concepts and are described based on the directions indicated in the drawings.

[0036] The terms used in this specification are provided only to describe specific embodiments of the present invention and are not intended to be limiting. Unless the context clearly indicates otherwise, expressions in the singular include expressions in the plural. In this specification, it should be understood that the terms "comprise" or "include" are intended to specify the features, quantities, steps, operations, components, parts, or any combination thereof mentioned in this specification, and are not intended to preclude the possibility of the presence or addition of at least one other feature, quantity, step, operation, component, part, or any combination thereof.

[0037] Figure 1is a plan view of a display device according to an embodiment. Figure 2 It is along Figure 1 A cross-sectional view taken along line AA'. Figure 3 Yes Figure 2 A cross-sectional view of the organic light-emitting device shown. Figure 4 As Figure 2 A cross-sectional view of an organic light-emitting device showing a modified example of the organic light-emitting device is shown.

[0038] Reference Figures 1 to 4 , a display device 1 according to an embodiment includes a substrate 2 , a first electrode 4 , a common light emitting layer 5 that emits light, and a second electrode 6 .

[0039] A plurality of sub-pixels 21, 22, and 23 are formed on substrate 2 at different locations of a common light-emitting layer 5 and share the common light-emitting layer 5 to generate light from light emission from the common light-emitting layer 5. In various implementations, the plurality of sub-pixels 21, 22, and 23 can be configured to include color filters within the sub-pixels so that light emitted from corresponding regions of the common light-emitting layer 5 can be filtered into different colors. In a specific implementation, the plurality of sub-pixels 21, 22, and 23 can be grouped to form a single pixel. A plurality of pixels can be formed on substrate 2. Substrate 2 can include a plurality of sub-pixels 21, 22, and 23.

[0040] The plurality of sub-pixels 21, 22, and 23 include a first sub-pixel 21, a second sub-pixel 22, and a third sub-pixel 23. The first sub-pixel 21, the second sub-pixel 22, and the third sub-pixel 23 are arranged in a specific spatial order such that the second sub-pixel 22 is disposed adjacent to one side (e.g., the left side) of the first sub-pixel 21, and the third sub-pixel 23 is disposed adjacent to one side (e.g., the left side) of the second sub-pixel 22.

[0041] In some implementations, when two sub-pixels are positioned adjacent to each other, the two sub-pixels are positioned relative to each other without any other sub-pixels positioned between the two sub-pixels.

[0042] In a specific implementation, to generate an image of a desired color, the plurality of sub-pixels 21, 22, and 23 may be configured to include color filters within their sub-pixels so that light emitted from corresponding regions of the common light-emitting layer 5 can be filtered into different colors. For example, the first sub-pixel 21 may be configured to include a red transmissive color filter to filter light emitted from its region within the common light-emitting layer 5 to output red light R, the second sub-pixel 22 may be configured to include a green transmissive color filter to filter light emitted from its region within the common light-emitting layer 5 to output green light G, and the third sub-pixel 23 may be configured to include a blue transmissive color filter to filter light emitted from its region within the common light-emitting layer 5 to output blue light B. However, this implementation of adjacent sub-pixels outputting light of different colors is merely an example, and other implementations of the color arrangement of adjacent sub-pixels are also possible.

[0043] Figure 1 The pixel is shown to include only three sub-pixels 21, 22, and 23, but other implementations with different numbers of adjacent sub-pixels are also possible. For example, a pixel can include four adjacent sub-pixels. When a pixel includes four sub-pixels that output light of different colors (e.g., red R, green G, and blue B), the pixel can also include a fourth sub-pixel configured to emit white light W.

[0044] In an implementation, the first to third sub-pixels 21, 22, and 23 may each be configured to have the same sub-pixel size. For example, the first to third sub-pixels 21, 22, and 23 may each be provided with the same width and the same height. Here, the width may refer to the width based on the Figure 1 The horizontal direction, height can refer to the vertical direction based on Figure 1 However, this implementation is only an example, and other implementations are also possible.

[0045] The first protective layer PS1 and the second protective layer PS2 may be provided in each of the first sub-pixel 21, the second sub-pixel 22, and the third sub-pixel 23. The first protective layer PS1 and the second protective layer PS2 may serve as dams that define the emission areas EA1, EA2, and EA3 of the sub-pixels 21, 22, and 23. Figure 2 In each of the first sub-pixel 21, the second sub-pixel 22, and the third sub-pixel 23, the first protection layer PS1 is disposed on the transparent layer 41, and the second protection layer PS2 is disposed on the first protection layer PS1. In the first sub-pixel 21, the second sub-pixel 22, and the third sub-pixel 23, the first protection layer PS1 and the second protection layer PS2 may be formed on the same layer.

[0046] The first electrode 4 is patterned separately for each sub-pixel 21, 22, and 23. In some implementations, one first electrode 4 is formed in the first sub-pixel 21, and another first electrode 4 is formed in the second sub-pixel 22. Additionally, another first electrode 4 is formed in the third sub-pixel 23. In some implementations, the first electrodes 4 provided in the first, second, and third sub-pixels 21, 22, and 23 are different portions of the first electrode 4. The first electrode 4 may function as an anode of the display device 1. A bank BK is provided to cover the edges of the first electrodes 4 provided in the first, second, and third sub-pixels 21, 22, and 23, respectively, thereby dividing the first, second, and third sub-pixels 21, 22, and 23 into regions where the bank BK, including the first and second protective layers PS1 and PS2, are provided, and regions where the bank BK is not provided. Thus, the first and second protective layers PS1 and PS2 may define a light-emitting region. For example, the first and second protective layers PS1 and PS2 may be provided in the non-light-emitting region, while the first and second protective layers PS1 and PS2 may not be provided in the light-emitting regions EA1, EA2, and EA3.

[0047] In the display device 1, the first electrode 4 is formed as a plurality of layers including the reflective layer 42. Therefore, the display device 1 can further improve light extraction efficiency using the microcavity characteristics.

[0048] Due to the microcavity characteristics, when the distance between the reflective layer 42 and the second electrode 6 is an integer multiple of half the wavelength (λ / 2) of the light emitted from the sub-pixel, constructive interference occurs and the light is amplified. In addition, when reflection and re-reflection are repeated between the reflective layer 42 and the second electrode 6, the microcavity characteristics allow the degree of light amplification to be continuously increased, thereby improving the external light extraction efficiency.

[0049] The common light-emitting layer 5 can be configured to emit white light including light components of different colors. For example, the common light-emitting layer 5 can be provided with a double-stacked structure including a blue light-emitting layer that emits blue light, a yellow-green light-emitting layer that emits yellow light, and a charge generation layer, thereby jointly emitting white light by combining the emitted blue and yellow light, or provided with a three-stacked structure including a blue light-emitting layer that emits blue light, a green light-emitting layer that emits green light, a red light-emitting layer that emits red light, and a charge generation layer, thereby jointly emitting white light by combining the emitted blue, green, and red light. In addition to the two color design examples described above, the common light-emitting layer 5 can be configured as other light-emitting structures to generate white light. For example, the common light-emitting layer 5 can be provided with multiple layers including more than three stacks, as long as the common light-emitting layer 5 can emit white light.

[0050] The common light emitting layer 5 may be formed as a common layer that spans the entire first to third sub-pixels 21, 22, and 23 and is shared by the entire first to third sub-pixels 21, 22, and 23. Therefore, the common light emitting layer 5 may cover the first electrode 4 provided in each sub-pixel and the first and second protective layers PS1 and PS2 provided in each sub-pixel and between the sub-pixels.

[0051] The second electrode 6 is provided to form an electric field together with the first electrode 4 and may function as a cathode. The second electrode 6 is provided on the top surface of the common light-emitting layer 5 opposite to the bottom surface of the common light-emitting layer 5 in contact with the first electrode 4, and may be provided across the common layer of the entire first to third sub-pixels 21, 22, and 23.

[0052] In the case of a top-emission display, the second electrode 6 may be configured as a transparent electrode that transmits light emitted by the common light-emitting layer 5 and the entire first to third sub-pixels 21, 22, and 23 while providing electrical constriction. In the case of a bottom-emission display, the second electrode 6 may be configured as an opaque electrode comprising a reflective material. In the case of a top-emission display, the second electrode 6 may be formed as a semi-transparent electrode to improve light extraction efficiency by utilizing microcavity characteristics. Since the display device utilizes microcavity characteristics to improve light extraction efficiency in a top-emission display, the second electrode formed as a semi-transparent electrode will be described as an example.

[0053] The sub-pixels formed based on the common light-emitting layer 5 (e.g., the first to third sub-pixels 21, 22, and 23) can be designed to include color filters, one color filter per sub-pixel, to filter the common light emitted by the common light-emitting layer 5 to generate different output lights from different sub-pixels according to the colors desired by the sub-pixels. For example, the color filter layer 9 is provided in each of the first to third sub-pixels 21, 22, and 23 to include different color filters at different sub-pixels to block specific colors from the light emitted from the common light-emitting layer 5 of each sub-pixel. Figure 1 In the specific example shown, the color filter layer 9 may include a first color filter 91 located in the first sub-pixel 21 to transmit red light and block the transmission of light of colors other than red light R. In this case, the first color filter 91 is a red color filter. Figure 1 In the embodiment of the present invention, the color filter layer 9 may include a second color filter 92 located in the second sub-pixel 22 to transmit green light and block the transmission of light of colors other than green light G. In this case, the second color filter 92 is a green color filter. In addition, Figure 1 The color filter layer 9 in the embodiment may include a third color filter 93 located in the third sub-pixel 23 to transmit blue light and block the transmission of light of colors other than blue light B. In this case, the third color filter 93 is a blue filter. Other designs of color filters that are arranged differently from the red, green, and blue colors described above are also possible.

[0054] In some implementations, the first to third color filters 91, 92, and 93 respectively provided in the first to third sub-pixels 21, 22, and 23 may be provided with the same size as the sub-pixel. In some implementations, the first to third color filters 91, 92, and 93 may be provided with a size different from that of the sub-pixel (e.g., by reducing or enlarging the size of the sub-pixel at a specific ratio).

[0055] Hereinafter, a stacked structure of the display device 1 according to the embodiment will be described in detail.

[0056] The display device 1 according to the embodiment includes a substrate 2 , an insulating layer 3 , a first electrode 4 , a first protective layer PS1 , a second protective layer PS2 , a common light emitting layer 5 , a second electrode 6 , a capping layer 7 , an encapsulation layer 8 , and a color filter layer 9 .

[0057] The substrate 2 may be a plastic film, a glass substrate, or a semiconductor substrate such as silicon.

[0058] The substrate 2 may be formed of or include a transparent material or an opaque material. A first sub-pixel 21, a second sub-pixel 22, and a third sub-pixel 23 are disposed on the substrate 2. The first sub-pixel 21 may be configured to emit red light R, the second sub-pixel 22 may be configured to emit blue light B, and the third sub-pixel 23 may be configured to emit green light G.

[0059] In some implementations, the display device 1 is formed as a top emission type in which the emitted light is emitted upward. Therefore, not only transparent materials but also opaque materials can be used as the material of the substrate 2. Color filters 91, 92, and 93 may be provided on the upper portions of the first to third sub-pixels 21, 22, and 23 from which light is emitted so as to transmit the above-mentioned colors of light.

[0060] The insulating layer 3 is formed on the substrate 2. The insulating layer 3 may include a plurality of stacked insulating layers 3a, 3b and 3c. The insulating layers 3a, 3b and 3c according to the embodiment may be stacked sequentially in their thickness direction and may include the same material. However, the insulating layers 3a, 3b and 3c are not limited thereto and may include different materials. In the insulating layer 3, circuit elements including a plurality of thin film transistors 31, 32 and 33, various signal wirings and capacitors are provided for each of the sub-pixels 21, 22 and 23. The signal wiring may include a gate line, a data line, a power line and a reference line. The thin film transistors 31, 32 and 33 may include a switching thin film transistor, a driving thin film transistor and a sensing thin film transistor. Each of the sub-pixels 21, 22 and 23 is defined by the intersection structure of the gate line and the data line.

[0061] The switching thin film transistor is switched according to a gate signal supplied to the gate line, and serves to supply a data voltage supplied from the data line to the driving thin film transistor.

[0062] The driving thin film transistor is switched according to the data voltage supplied from the switching thin film transistor, and serves to generate a data current from power supplied from the power line and supply the data current to the first electrode 4 .

[0063] The sensing thin film transistor is used to sense the threshold voltage deviation of the driving thin film transistor, which is one cause of image quality degradation. The sensing thin film transistor responds to a sensing control signal supplied from the gate line or a separate sensing line and supplies the current of the driving thin film transistor to the reference line.

[0064] The capacitor is used to maintain the data voltage supplied to the driving thin film transistor within one frame. The capacitor is connected to the gate terminal and the source terminal of the driving thin film transistor, respectively.

[0065] A first transistor 31, a second transistor 32, and a third transistor 33 are provided within the first insulating layer 3a for the sub-pixels 21, 22, and 23, respectively. The first transistor 31 can be connected to the first electrode 4 provided on the first sub-pixel 21 and can apply a driving voltage for emitting light of a color corresponding to the first sub-pixel 21.

[0066] The second transistor 32 may be connected to the first electrode 4 disposed on the second sub-pixel 22 and may apply a driving voltage for emitting light of a color corresponding to the second sub-pixel 22 .

[0067] The third transistor 33 may be connected to the first electrode 4 disposed on the third sub-pixel 23 and may apply a driving voltage for emitting light of a color corresponding to the third sub-pixel 23 .

[0068] When the first sub-pixel 21, the second sub-pixel 22, and the third sub-pixel 23 receive gate signals from the gate lines using transistors 31, 32, and 33, respectively, a predetermined current is supplied to the light-emitting layer according to the data voltage of the data line. As a result, the light-emitting layer of each of the first sub-pixel 21, the second sub-pixel 22, and the third sub-pixel 23 can emit light having a predetermined brightness according to the predetermined current.

[0069] The first insulating layer 3a protects the transistors 31, 32, and 33. The first insulating layer 3a may be formed of or include an organic insulating material, but the first insulating layer 3a is not necessarily limited thereto. The first insulating layer 3a may be formed of or include an inorganic insulating material. The transistors 31, 32, and 33 may be located within the first insulating layer 3a.

[0070] The connection electrode CE may be provided in each of the sub-pixels 21, 22, and 23 on the first insulating layer 3a. The second insulating layer 3b may be provided on the first insulating layer 3a. The connection electrode CE may be provided within the second insulating layer 3b, but the connection electrode CE is not limited thereto. The connection electrode CE is patterned for each of the first to third sub-pixels 21, 22, and 23. The connection electrode CE may be electrically connected to the transistors 31, 32, and 33. The second insulating layer 3b may be formed of or include an organic insulating material, but is not necessarily limited thereto. The second insulating layer 3b may be formed of or include an inorganic insulating material.

[0071] On the second insulating layer 3b, a reflective layer (described later) of the first sub-pixel 21 or a first electrode 4 may be provided. The first electrode 4 is patterned for each of the first to third sub-pixels 21, 22, and 23. The first electrode 4 is connected to the driving thin film transistor provided in the insulating layer 3. For example, the first electrode 4 may be electrically connected to the transistors 31, 32, and 33 via the connection electrode CE described above.

[0072] The display device 1 according to the embodiment is formed as a top emission type. In an implementation, the first electrode 4 may be configured to reflect light emitted from the common light-emitting layer 5 upward. In this case, the first electrode 4 may have a double-layer structure including a reflective layer 42 (or a reflective electrode or a reflective plate) for reflecting light and a transparent layer 41 (or a transparent electrode or an anode electrode) for supplying holes to the common light-emitting layer 5.

[0073] The reflective layer 42 can reflect light emitted from the common light-emitting layer 5 of each of the sub-pixels 21, 22, and 23, which is emitted toward the reflective layer 42, toward the second electrode 6 or the encapsulation layer 8. In addition, the reflective layer 42 is used to realize microcavity characteristics through reflection and re-reflection with the second electrode 6. In an implementation, the reflective layer 42 may include a reflective material for reflecting light. For example, the reflective material may be or include a metal, but is not necessarily limited thereto. The reflective material may be or include any other material, as long as it can reflect light. For example, the reflective material may include Ti / Al, but is not limited thereto.

[0074] Since the reflective layer 42 is provided at a position relatively lower than the common light-emitting layer 5 from which light is emitted, the reflective layer 42 can reflect the light emitted from the common light-emitting layer 5 upward. Here, upward refers to the direction in which the user can perceive the light. For example, upward can refer to the side where the encapsulation layer 8 or the color filter layer 9 is provided. Therefore, compared with a case without the reflective layer 42, the first sub-pixel 21, the second sub-pixel 22, and the third sub-pixel 23 can have improved light efficiency, and the user can perceive a high-brightness image (i.e., a clear image) due to the improved light efficiency.

[0075] As described above, by having a first electrode 4 composed of or including multiple layers, including a reflective layer 42, the display device 1 can further improve light extraction efficiency by utilizing microcavity characteristics. The reflective layer 42 may be disposed within the third insulating layer 3c, but is not limited thereto. The reflective layer 42 may include a first reflective layer 42a, a second reflective layer 42b, and a third reflective layer 42c. The first reflective layer 42a may be electrically connected to the connection electrode CE via a via VIA. In the first sub-pixel 21, the first reflective layer 42a may include a first reflective electrode RE1 that overlaps with the transparent layer 41 of the first sub-pixel 21. The second reflective layer 42b may be disposed on the first reflective layer 42a and may be electrically connected to the first reflective layer 42a. In the second sub-pixel 22, the second reflective layer 42b may include a second reflective electrode RE2 that overlaps with the transparent layer 41 of the second sub-pixel 22. The distance between the first reflective electrode RE1 and the transparent layer 41 may be greater than the distance between the second reflective electrode RE2 and the transparent layer 41. The third reflective layer 42c may be disposed on the second reflective layer 42b and may be electrically connected to the second reflective layer 42b. In the third sub-pixel 23, the third reflective layer 42c may include a third reflective electrode RE3 that overlaps with the transparent layer 41 of the third sub-pixel 23. The distance between the second reflective electrode RE2 and the transparent layer 41 may be greater than the distance between the third reflective electrode RE3 and the transparent layer 41. The third reflective electrode RE3 may directly contact the transparent layer 41, but is not limited to this. The third reflective layer 42c may directly contact the transparent layer 41 corresponding to each of the sub-pixels 21, 22, and 23, but is not limited to this. Although the first reflective layer 42a and the second reflective layer 42b are located within the third insulating layer 3c, the third reflective layer 42c may be located on the top surface of the third insulating layer 3c, but is not limited to this. The second electrodes 6 in the emission areas EA1, EA2, and EA3 of the sub-pixels 21, 22, and 23 may be located on the same line. Therefore, the distance relationship between the reflective electrodes RE1 , RE2 and RE3 and the transparent layer 41 in the sub-pixels 21 , 22 and 23 may be the same as the distance relationship between the reflective electrodes RE1 , RE2 and RE3 and the second electrode 6 .

[0076] The reflective layers 42 of the sub-pixels 21 , 22 , and 23 may be electrically connected to the transistors 31 , 32 , and 33 through the connection electrodes CE.

[0077] Therefore, since the light extraction efficiency of different colors of light can be improved by reflection and re-reflection between the reflective electrodes RE1, RE2, and RE3 and the second electrode 6 according to the spacing distance, the reflective electrodes RE1, RE2, and RE3 can be formed to have various spacing distances (or resonance distances) from the second electrode 6. As a result, the light extraction efficiency of red light can be improved in the first sub-pixel 21, the light extraction efficiency of green light can be improved in the second sub-pixel 22, and the light extraction efficiency of blue light can be improved in the third sub-pixel 23.

[0078] The transparent layer 41 is provided on the reflective layer 42. The transparent layer 41 is used to supply holes to the common light-emitting layer 5. The transparent layer 41 may be transparent so that light reflected from the reflective layer 42 can propagate upward. The transparent layer 41 may be formed of or include a transparent material, but is not limited thereto. The transparent layer 41 may be formed in the form of a thin film of any metal material capable of transmitting light. For example, the transparent layer 41 may include titanium nitride (TiN), but is not limited thereto. The transparent layer 41 may be formed in the form of a very thin film so that light reflected from the reflective layer 42 can propagate upward. For example, the thickness of the transparent layer 41 may be approximately 5 nm or less. For example, the thickness of the transparent layer 41 may be approximately 3 nm or less, but is not limited thereto.

[0079] The transparent layer 41 can be electrically connected to the reflective layer 42 by directly contacting the reflective layer 42, or can be electrically connected to the reflective layer 42 by being indirectly connected to the reflective layer 42 through a contact hole. The reflective layer 42 is respectively connected to the first to third transistors 31, 32, and 33 through another contact hole, so that the driving voltage provided by each of the first to third transistors 31, 32, and 33 can be applied to the transparent layer 41. When the driving voltage is applied from the first to third transistors 31, 32, and 33, the transparent layer 41 can supply holes to the common light-emitting layer 5. In each of the sub-pixels 21, 22, and 23, the transparent layer 41 can directly contact the third reflective layer 42c and can reflect the step difference formed by the third reflective layer 42c.

[0080] The transparent layer 41 may be provided for each of the first to third sub-pixels 21, 22, and 23 so as to have substantially the same height above the top surface of the reflective layer 42 or the insulating layer 3. Furthermore, the reflective layer 42 may have the same width as the transparent layer 41, but is not necessarily limited thereto. The reflective layer 42 may have a greater width than the transparent layer 41 to further increase the amount of light reflected upward.

[0081] The transparent layer 41 in the sub-pixels 21, 22 and 23 is provided in the light-emitting areas EA1, EA2 and EA3, and may also be provided in a portion of the non-light-emitting area. However, the transparent layer 41 provided in the sub-pixels 21, 22 and 23 may be physically separated from the transparent layer 41 provided in the adjacent sub-pixels 21, 22 and 23. The physical separation between the transparent layer 41 of the sub-pixels 21, 22 and 23 and the transparent layer 41 of the adjacent sub-pixels 21, 22 and 23 may be performed by the first etching described later. In the process of separating the transparent layer 41 by the first etching, the first protective layer PS1 between the sub-pixels 21, 22 and 23 may also be separated together with the transparent layer 41. Therefore, the first protective layer PS1 may not be provided in an area where the transparent layer 41 is not provided. For example, as Figure 2As shown, the first protective layer PS1 may not be provided in the separation area between the transparent layer 41 of the first sub-pixel 21 and the transparent layer 41 of the second sub-pixel 22. The first protective layer PS1 may be provided on the transparent layer 41. The first protective layer PS1 may be made of, for example, silicon nitride SiN x , silicon oxide SiO x , aluminum oxide Al2O3, etc. or include these inorganic materials. However, the embodiments of the present disclosure are not limited thereto. For example, the first protective layer PS1 may include aluminum oxide Al2O3, but is not limited thereto.

[0082] The second protective layer PS2 may be disposed on the first protective layer PS1. The second protective layer PS2 may be disposed on the boundaries of adjacent sub-pixels 21, 22, and 23. The second protective layer PS2 may be disposed in the non-luminous regions of the sub-pixels 21, 22, and 23, and may not be disposed in the luminous regions EA1, EA2, and EA3. Unlike the first protective layer PS1, the second protective layer PS2 may be disposed in a region where the transparent layer 41 is not disposed. Therefore, as Figure 2 As shown, in the region where the transparent layer 41 of adjacent sub-pixels 21, 22, and 23 is separated, the second protective layer PS2 may directly contact the underlying insulating layer 3 (e.g., the third insulating layer 3c). In addition, in the region where the transparent layer 41 of adjacent sub-pixels 21, 22, and 23 is separated, the second protective layer PS2 may directly contact the side surface of the first protective layer PS1 and the side surface and top surface of the transparent layer 41, respectively. The second protective layer PS2 may be made of, for example, silicon nitride SiN x , silicon oxide SiO x , aluminum oxide Al2O3, etc. or include these inorganic materials. However, the embodiments of the present disclosure are not limited thereto. For example, the second protective layer PS2 may include silicon nitride SiN x or silicon oxide SiO x , but not limited to this.

[0083] A common light-emitting layer 5 is formed on the first electrode 4 and the protective layers PS1 and PS2. The common light-emitting layer 5 may also be formed on the second protective layer PS2 disposed between the plurality of sub-pixels 21, 22, and 23. The common light-emitting layer 5 may contact the top surface of the transparent layer 41 of the first electrode 4. The common light-emitting layer 5 may directly contact the side surfaces of the first protective layer PS1 and the side and top surfaces of the second protective layer PS2.

[0084] According to an embodiment, the organic light emitting device (OLED) may include a first electrode (ANO) 4 , a second electrode (CAT) 6 , and a common light emitting layer 5 between the first electrode 4 and the second electrode 6 .

[0085] The common light emitting layer 5 may be configured to emit white light W. To this end, the common light emitting layer 5 may be formed to include a plurality of stacks emitting light of different colors. Specifically, the common light emitting layer 5 may be formed to include a first stack, a second stack, and a charge generation layer (CGL) disposed between the first stack and the second stack.

[0086] The second electrode 6 is formed on the common light emitting layer 5. The second electrode 6 may function as a cathode of the display device 1. Like the common light emitting layer 5, the second electrode 6 is also formed in the sub-pixels 21, 22, and 23 and between the sub-pixels.

[0087] In the display device 1 according to the embodiment, the second electrode 6 can be formed as a semi-transparent electrode to create light-efficient white light in a top-emission manner. Therefore, a microcavity effect can be obtained for each of the first to third sub-pixels 21, 22, and 23. When the second electrode 6 is formed as a semi-transparent electrode, the microcavity effect can be obtained by repeated reflection and re-reflection of light between the second electrode 6 and the reflective layer 42, thereby improving light extraction efficiency.

[0088] Furthermore, since the second electrode 6 is formed on the top surface of the common light-emitting layer 5, the second electrode 6 can be formed to follow the contour of the common light-emitting layer 5. Since the common light-emitting layer 5 is formed to follow the contour of the transparent layer 41 of the first electrode 4 in the light-emitting region, the second electrode 6 can be formed to follow the contour of the transparent layer 41 of the first electrode 4. In addition, the capping layer 7 on the second electrode 6 can also be formed to follow the contour of the second electrode 6.

[0089] The capping layer 7 may be formed of or include an inorganic insulating material, but is not limited thereto. The capping layer 7 may be provided on the second electrode 6 to protect the organic light emitting device (OLED).

[0090] The encapsulation layer 8 is formed on the second electrode 6 and serves to prevent external moisture from penetrating into the common light-emitting layer 5. Such an encapsulation layer 8 may be formed of or include an inorganic insulating material, or may be formed to have a structure in which an inorganic insulating material and an organic insulating material are alternately stacked, but is not necessarily limited thereto.

[0091] The color filter layer 9 is formed on the encapsulation layer 8. The color filter layer 9 may be formed to include a first color filter 91 of red R provided in the first sub-pixel 21, a second color filter 92 of green G provided in the second sub-pixel 22, and a third color filter 93 of blue B provided in the third sub-pixel 23, but is not necessarily limited thereto.

[0092] like Figure 3 As shown, the common light emitting layer 5 may be formed to include a first stack EL1 , a second stack EL2 , and a first charge generation layer CGL1 disposed on the first electrode 4 .

[0093] The first stack EL1 is disposed on the first electrode 4 and may be formed to have a structure in which a hole injection layer HIL, a hole transport layer HTL, a blue B emission layer EML1 , and an electron transport layer ETL are sequentially stacked.

[0094] The first stack EL1 may also be provided between the first sub-pixel 21 and the second sub-pixel 22 and between the second sub-pixel 22 and the third sub-pixel 23 (ie, on the bank BK).

[0095] The first charge generation layer CGL1 is used to supply charges to the first stack EL1 and the second stack EL2. The first charge generation layer CGL1 may be formed to include an N-type charge generation layer for supplying electrons to the first stack EL1 and a P-type charge generation layer for supplying holes to the second stack EL2. The N-type charge generation layer may be formed to include a metal material as a dopant.

[0096] The second stack EL2 is disposed on the first stack EL1 and may be formed to have a structure in which a hole transport layer HTL, a yellow-green YG emission layer EML2 , an electron transport layer ETL, and an electron injection layer EIL are sequentially stacked.

[0097] The second stack EL2 may also be provided between the first sub-pixel 21 and the second sub-pixel 22 and between the second sub-pixel 22 and the third sub-pixel 23 (ie, on the bank BK).

[0098] Results, such as Figure 2 As shown, the common light emitting layer 5 may be provided as a common layer throughout the first to third sub-pixels 21 , 22 and 23 .

[0099] like Figure 4 As shown, according to an embodiment, the common light-emitting layer 5_1 of the organic light-emitting device (OLED) may be formed to include a first stack EL1, a second stack EL2, a third stack EL3, a first charge generation layer CGL1 between the first stack EL1 and the second stack EL2, and a second charge generation layer CGL2 between the second stack EL2 and the third stack EL3, which are arranged on the first electrode 4.

[0100] The first stack EL1 is disposed on the first electrode 4 and may be formed to have a structure in which a hole injection layer HIL, a hole transport layer HTL, a blue B emission layer EML1 , and an electron transport layer ETL are sequentially stacked.

[0101] The first stack EL1 may also be provided between the first sub-pixel 21 and the second sub-pixel 22 and between the second sub-pixel 22 and the third sub-pixel 23 (ie, on the bank BK).

[0102] The first charge generation layer CGL1 is used to supply charges to the first stack EL1 and the second stack EL2. The first charge generation layer CGL1 may be formed to include an N-type charge generation layer for supplying electrons to the first stack EL1 and a P-type charge generation layer for supplying holes to the second stack EL2. The N-type charge generation layer may be formed to include a metal material as a dopant.

[0103] The first charge generation layer CGL1 may also be disposed between the first sub-pixel 21 and the second sub-pixel 22, and between the second sub-pixel 22 and the third sub-pixel 23 (i.e., on the bank BK). Furthermore, in the display device 1 according to an embodiment, since the common light-emitting layer 5 is also disposed between the sub-pixels 21, 22, and 23, when one of the sub-pixels emits light, lateral leakage current may occur through the first charge generation layer CGL1 to the adjacent sub-pixels 21, 22, and 23. However, since the bank BK having a specific height is disposed between the sub-pixels 21, 22, and 23, lateral leakage current may be prevented from occurring due to a longer current path. Furthermore, since the bank BK has an asymmetric shape, the thickness of the first charge generation layer CGL1 may be reduced on at least one side of the bank BK. As a result, the first charge generation layer CGL1 may be physically separated on at least one side of the bank BK. A detailed description of this will be provided later.

[0104] The second stack EL2 is disposed on the first stack EL1 and may be formed to have a structure in which a hole transport layer HTL, a green G emission layer EML2 , and an electron transport layer ETL are sequentially stacked.

[0105] The second stack EL2 may also be provided between the first sub-pixel 21 and the second sub-pixel 22 and between the second sub-pixel 22 and the third sub-pixel 23 (ie, on the bank BK).

[0106] The second charge generation layer CGL2 is used to supply charges to the second stack EL2 and the third stack EL3. The second charge generation layer CGL2 may be formed to include an N-type charge generation layer for supplying electrons to the second stack EL2 and a P-type charge generation layer for supplying holes to the third stack EL3. The N-type charge generation layer may be formed to include a metal material as a dopant.

[0107] The second charge generation layer CGL2 may also be disposed between the first sub-pixel 21 and the second sub-pixel 22, and between the second sub-pixel 22 and the third sub-pixel 23 (i.e., on the bank BK). Furthermore, in the display device 1 according to the embodiment, since the common light-emitting layer 5 is also disposed between the sub-pixels 21, 22, and 23, when one of the sub-pixels emits light, lateral leakage current may occur through the second charge generation layer CGL2 to the adjacent sub-pixels 21, 22, and 23. However, since the bank BK having a specific height is disposed between the sub-pixels 21, 22, and 23, the current path can be prevented from becoming longer, thereby preventing lateral leakage current from occurring. Furthermore, since the bank BK has an asymmetric shape, the thickness of the second charge generation layer CGL2 can be reduced on at least one side of the bank BK. As a result, the second charge generation layer CGL2 can be physically separated on at least one side of the bank BK. A detailed description of this will be provided later.

[0108] The third stack EL3 is disposed on the second stack EL2 and may be formed to have a structure in which a hole transport layer HTL, a red R emission layer EML3 , an electron transport layer ETL, and an electron injection layer EIL are sequentially stacked.

[0109] Return to reference Figure 2 A second electrode 6 is formed on the common light emitting layer 5, and an encapsulation layer 8 is formed on the second electrode 6. A color filter layer 9 is formed on the encapsulation layer 8.

[0110] Although not shown, a black matrix for preventing color mixing between sub-pixels may be provided between the first to third color filters 91 , 92 , 93 .

[0111] Figure 5 yes Figure 2 Magnified view of area Q1 in FIG.

[0112] Reference Figures 1 to 5 Of the top surfaces 41a1 and 41a2 of the transparent layer 41, the top surface 41a1 located in the first light-emitting area EA1 may directly contact the common light-emitting layer 5, and the top surface 41a2 located in the non-light-emitting area may directly contact the first protective layer PS1. The bottom surface PS1a of the first protective layer PS1 may directly contact the transparent layer 41 in the non-light-emitting area, and the top surface PS1b of the first protective layer PS1 may directly contact the second protective layer PS2 in the non-light-emitting area. The side surface PS1c of the first protective layer PS1 may directly contact the common light-emitting layer 5 at the boundary between the first light-emitting area EA1 and the non-light-emitting area. The second protective layer PS2 may not be provided in the first light-emitting area EA1. The common light-emitting layer 5 may directly contact the side surfaces of the second protective layer PS2 in the first light-emitting area EA1 and the top surface of the transparent layer 41.

[0113] The transparent layer 41 may have a first thickness t1. The first thickness t1 may be approximately 5 nm or less, but is not limited thereto. For example, the first thickness t1 may be approximately 3 nm or less, but is not limited thereto. The transparent layer 41 has a small thickness so that it has a transparent property that allows light reflected from the reflective layer 42 to propagate upward.

[0114] Figures 6 to 15 1 is a cross-sectional view illustrating respective process steps of a method for manufacturing a display device according to an embodiment.

[0115] Hereinafter, a method for manufacturing the display device 1 according to the embodiment will be described. In the following description of the method for manufacturing the display device 1, reference to the method for manufacturing the display device 1 will be omitted. Figures 1 to 5 The same parts as those described above are described repeatedly.

[0116] A first insulating layer 3 a , transistors 31 , 32 , and 33 , a second insulating layer 3 b , a connection electrode CE, a third insulating layer 3 c , a through hole VIA, and a reflective layer 42 may be formed on the substrate 2 .

[0117] In some implementations, the substrate 2 may be a plastic film, a glass substrate, or a semiconductor substrate such as silicon.

[0118] The substrate 2 may be formed of or include a transparent material or an opaque material. A first sub-pixel 21, a second sub-pixel 22, and a third sub-pixel 23 are disposed on the substrate 2. The first sub-pixel 21 may be configured to emit red light R, the second sub-pixel 22 may be configured to emit blue light B, and the third sub-pixel 23 may be configured to emit green light G.

[0119] The insulating layer 3 is formed on the substrate 2. The insulating layer 3 may include a plurality of stacked insulating layers 3a, 3b and 3c. According to an embodiment, the insulating layers 3a, 3b and 3c may be stacked sequentially in the thickness direction and may include the same material. However, it is not limited thereto. The insulating layers 3a, 3b and 3c may include different materials. In the insulating layer 3, circuit elements including a plurality of thin film transistors 31, 32 and 33, various signal wirings and capacitors are provided for each of the sub-pixels 21, 22 and 23. The signal wiring may include a gate line, a data line, a power line and a reference line. The thin film transistors 31, 32 and 33 may include a switching thin film transistor, a driving thin film transistor and a sensing thin film transistor. Each of the sub-pixels 21, 22 and 23 is defined by the intersection structure of the gate line and the data line.

[0120] A first transistor 31 , a second transistor 32 and a third transistor 33 are provided in the first insulating layer 3 a for the sub-pixels 21 , 22 and 23 , respectively.

[0121] The first insulating layer 3a protects the transistors 31, 32, and 33. The first insulating layer 3a may be formed of or include an organic insulating material, but the first insulating layer 3a is not necessarily limited thereto. The first insulating layer 3a may be formed of or include an inorganic insulating material. The transistors 31, 32, and 33 may be located within the first insulating layer 3a.

[0122] The connection electrode CE may be provided in each of the sub-pixels 21, 22, and 23 on the first insulating layer 3a. The second insulating layer 3b may be provided on the first insulating layer 3a. The connection electrode CE may be provided within the second insulating layer 3b, but the connection electrode CE is not limited thereto. The connection electrode CE is patterned for each of the first to third sub-pixels 21, 22, and 23. The connection electrode CE may be electrically connected to the transistors 31, 32, and 33. The second insulating layer 3b may be formed of or include an organic insulating material, but is not necessarily limited thereto. The second insulating layer 3b may be formed of or include an inorganic insulating material.

[0123] The reflective layer 42 can reflect light emitted from the common light-emitting layer 5 of each of the sub-pixels 21, 22, and 23, which is emitted toward the reflective layer 42, toward the second electrode 6 or the encapsulation layer 8. Furthermore, the reflective layer 42 is configured to realize microcavity characteristics through reflection and re-reflection with the second electrode 6. To this end, the reflective layer 42 may include a reflective material for reflecting light. For example, the reflective material may be metal, but is not necessarily limited thereto. The reflective material may be any other material as long as it can reflect light. For example, the reflective material may include Ti / Al, but is not limited thereto.

[0124] The reflective layers 42 of the sub-pixels 21 , 22 , and 23 may be electrically connected to the transistors 31 , 32 , and 33 through the connection electrodes CE.

[0125] Reference Figure 2 and Figure 7 , in the sub-pixels 21, 22 and 23, a transparent layer 41' is deposited (or formed) on the entire surface of the reflective layer 42. The transparent layer 41' may be formed of or include a transparent material, but is not limited thereto. The transparent layer 41' may be formed in the form of a thin film of any metal material capable of transmitting light. For example, the transparent layer 41' may include titanium nitride (TiN), but is not limited thereto. The transparent layer 41' may be formed in the form of a very thin film so that light reflected from the reflective layer 42 can propagate upward. For example, the thickness of the transparent layer 41' may be about 5 nm or less. For example, the thickness of the transparent layer 41' may be about 3 nm or less, but is not limited thereto.

[0126] Then, refer to Figure 2 and Figure 8 , depositing a first protective layer PS1' on the entire surface of the transparent layer 41'. The first protective layer PS1' may be made of a material such as silicon nitride SiN x, silicon oxide SiO x , aluminum oxide Al2O3, etc. or include these inorganic materials. However, the embodiments of the present disclosure are not limited thereto. For example, the first protective layer PS1' may include aluminum oxide Al2O3, but is not limited thereto.

[0127] Then, refer to Figure 2 and Figure 8 , a first photoresist PR1 is formed on the first protective layer PS1'. The first photoresist PR1 can be used as a mask in the first etching process described later. The first etching process can be to remove the transparent layer (see FIG. 1 ) located in the sub-pixels 21, 22, and 23. Figure 2 41 in the figure) and the transparent layers (see Figure 2 Therefore, the first photoresist PR1 is formed on Figure 2 The middle transparent layer 41 is respectively disposed in regions in the sub-pixels 21, 22, and 23. The first photoresist PR1 is not disposed in a region where the transparent layer 41 is not disposed, and may expose the first protection layer PS1' in the region.

[0128] like Figure 8 As shown, the first protective layer PS1' and the transparent layer 41' are first etched using the first photoresist PR1 as a mask. The first etching may be a dry etching method. The etching gas used in the first etching may have a good etching rate for the first protective layer PS1' and the transparent layer 41'. For example, the difference in etching rate between the first protective layer PS1' and the transparent layer 41' by the etching gas used in the first etching may be approximately 10% or less, but embodiments of the present disclosure are not limited thereto.

[0129] Then, if Figure 2 and Figure 9 As shown, in Figure 8After the first etching of the transparent layer 41' and the first protective layer PS1' in the transparent layer 41, a transparent layer 41 and a first protective layer PS1" are formed. After the first etching, the first photoresist PR1 is removed. The removal of the first photoresist PR1 can be performed using an ashing process. The ashing process may include an oxygen plasma process. In other words, when the first photoresist PR1 is exposed to oxygen OXYGEN in the form of plasma, the first photoresist PR1 can be removed. As described above, the transparent layer 41 is manufactured to have a very small thickness in order to increase the light transmittance. If the thin transparent layer 41 is exposed to oxygen plasma, it may oxidize. If the transparent layer 41 oxidizes, the thickness of the transparent layer 41 may vary in different parts (areas within the light emitting areas EA1, EA2 and EA3), and therefore, the display quality may deteriorate. However, in the case of the display device according to the embodiment, during the process of removing the first photoresist PR1, since the first protective layer PS1" is provided on the transparent layer 41, the oxidation of the transparent layer 41 can be prevented in advance.

[0130] like Figure 2 and Figure 10 As shown, a second protective layer PS2' is deposited on the entire surface of the first etched transparent layer 41 and the first protective layer PS1". The second protective layer PS2' can be made of silicon nitride SiN x , silicon oxide SiO x , aluminum oxide Al2O3, etc. or include these inorganic materials. However, the embodiments of the present disclosure are not limited thereto. For example, the second protective layer PS2' may include silicon nitride SiN x or silicon oxide SiO x In a region where the transparent layer 41 is not provided, the second protection layer PS2 ′ may directly contact the insulating layer 3 (eg, the third insulating layer 3 c ).

[0131] Then, if Figure 2 and Figure 11 As shown, a second photoresist PR2 is formed on the second protective layer PS2'. The second photoresist PR2 may be formed in the non-luminescent area of ​​each of the sub-pixels 21, 22, and 23, and may not be formed in the luminescent areas EA1, EA2, and EA3. The second photoresist PR2 may be used as a mask in the second etching process. The second etching may be a process of removing the second protective layer PS2' located in each of the luminescent areas EA1, EA2, and EA3 and exposing the top surface of the first protective layer PS1" on the luminescent areas EA1, EA2, and EA3.

[0132] like Figure 11As shown, the second protective layer PS2' is subjected to a second etching using the second photoresist PR2 as a mask. The second etching may be a dry etching method. The etching gas used in the second etching may have a good etching rate for the second protective layer PS2'. In the second etching, the second protective layer PS2' may be etched, but the first protective layer PS1" and the transparent layer 41 may not be etched. For example, the etching rate of the second protective layer PS2' to the etching gas may be three times or more of the etching rate of the first protective layer PS1" to the etching gas and the etching rate of the transparent layer 41 to the etching gas, respectively. For example, the etching rate of the second protective layer PS2' to the etching gas may be about seven times or more of the etching rate of the first protective layer PS1" to the etching gas, and the etching rate of the second protective layer PS2' to the etching gas may be about four times or more of the etching rate of the transparent layer 41 to the etching gas. For example, the etching rate of the second protective layer PS2' to the etching gas: the etching rate of the first protective layer PS1" to the etching gas: the etching rate of the transparent layer 41 to the etching gas may be 28:4:7. However, the embodiments of the present disclosure are not limited thereto.

[0133] In the second etching process, even if the etching rate of the second protective layer PS2′ to the etching gas is approximately four times or more than the etching rate of the transparent layer 41 to the etching gas, the transparent layer 41 may be partially etched by the etching gas when overetching occurs. However, according to the manufacturing method of the display device 1 according to the embodiment, in the second etching process, since the first protective layer PS1″ is provided on the transparent layer 41 and protects the transparent layer 41, etching of the transparent layer 41 does not occur.

[0134] Then, if Figure 2 and Figure 12 As shown, in Figure 11After the second etching of the second protective layer PS2' in the sub-pixels 21, 22 and 23, the second protective layer PS2 is formed. The second protective layer PS2 may not be provided in the light-emitting areas EA1, EA2 and EA3 of the sub-pixels 21, 22 and 23. After the second etching, the second photoresist PR2 is removed. The removal of the second photoresist PR2 can be performed using an ashing process. The ashing process may include an oxygen plasma process. In other words, when the second photoresist PR2 is exposed to oxygen OXYGEN in the form of plasma, the second photoresist PR2 can be removed. As described above, the transparent layer 41 is manufactured to have a very small thickness in order to increase the light transmittance. If the thin transparent layer 41 is exposed to oxygen plasma, it may oxidize. If the transparent layer 41 oxidizes, the thickness of the transparent layer 41 may vary in different parts (areas within the light-emitting areas EA1, EA2 and EA3), and therefore, the display quality may deteriorate. However, in the case of the display device according to the embodiment, during the process of removing the second photoresist PR2 , since the first protection layer PS1 ″ is disposed on the transparent layer 41 , oxidation of the transparent layer 41 may be prevented in advance.

[0135] Then, if Figure 2 and Figure 13 As shown, a third etching is performed. The third etching may be a wet etching. The etchant used in the third etching may have a good etching rate for the first protective layer PS1″. In the third etching, the first protective layer PS1″ may be etched, but the second protective layer PS2 and the transparent layer 41 may not be etched. For example, the etching rate of the first protective layer PS1″ to the etchant may be five times or more of the etching rate of the second protective layer PS2 to the etching gas and the etching rate of the transparent layer 41 to the etchant, respectively. For example, the etching rate of the first protective layer PS1″ to the etchant may be about 100 times or more of the etching rate of the second protective layer PS2 to the etchant, and the etching rate of the first protective layer PS1″ to the etchant may be about eight times or more of the etching rate of the transparent layer 41 to the etchant. For example, the etching rate of the first protective layer PS1″ to the etchant: the etching rate of the second protective layer PS2 to the etchant: the etching rate of the transparent layer 41 to the etchant may be 1000:10:1. However, the embodiments of the present disclosure are not limited thereto.

[0136] exist Figure 13 After the third etching process in Figure 14 As shown, a first protective layer PS1 is formed. The first protective layer PS1 may expose the top surface of the transparent layer 41 in the emission areas EA1, EA2, and EA3.

[0137] Then, if Figure 2 and Figure 15 As shown, the common light emitting layer 5 and the second electrode 6 are sequentially stacked on the protective layers PS1 and PS2 and the transparent layer 41 .

[0138] The common light-emitting layer 5 can be configured to emit white light. For example, the common light-emitting layer 5 can be configured to have a double-layer structure including a blue light-emitting layer, a yellow-green light-emitting layer, and a charge generation layer, or a triple-layer structure including a blue light-emitting layer, a green light-emitting layer, a red light-emitting layer, and a charge generation layer, thereby emitting white light. However, the common light-emitting layer 5 is not necessarily limited to this. The common light-emitting layer 5 can be configured to have multiple layers including more than three stacks, as long as the common light-emitting layer 5 can emit white light.

[0139] The common light emitting layer 5 may be formed as a common layer across the first to third sub-pixels 21, 22, and 23. Therefore, the common light emitting layer 5 may cover the first electrodes 4 provided in each sub-pixel and the first and second protective layers PS1 and PS2 respectively provided between the sub-pixels.

[0140] The second electrode 6 is provided to form an electric field together with the first electrode 4 and may function as a cathode. The second electrode 6 is provided on the top surface of the common light-emitting layer 5 opposite to the bottom surface of the common light-emitting layer 5 in contact with the first electrode 4, and may be provided across the common layer of the entire first to third sub-pixels 21, 22, and 23.

[0141] In the case of a top-emission type, the second electrode 6 can be configured as a transparent electrode. In the case of a bottom-emission type, the second electrode 6 can be configured as an opaque electrode including a reflective material. In the case of a top-emission type, the second electrode 6 can be formed as a semi-transparent electrode to improve light extraction efficiency by utilizing microcavity characteristics. Since the display device of the top-emission type utilizes the microcavity characteristics to improve light extraction efficiency, the second electrode formed as a semi-transparent electrode will be described as an example.

[0142] Hereinafter, a display device according to other embodiments will be described. In the description of the following embodiments, the description of the display device according to other embodiments will be omitted. Figures 1 to 15 Detailed description or redundant description of components that are identical or similar to those described in .

[0143] Figure 16 is a cross-sectional view of a display device according to another embodiment.

[0144] Reference Figure 16 The display device 1_1 according to the embodiment and the display device 1_1 according to the embodiment Figure 2 and Figure 5 The display device 1 of FIG. 4 is different in that it includes a transparent layer 41_1 .

[0145] The top surface 41a1_1 in the first light emitting area EA1 of the transparent layer 41_1 may include surface irregularities. For example, the surface roughness of the surface 41a1_1 in the first light emitting area EA1 of the transparent layer 41_1 may be greater than the surface roughness of the top surface 41a2 in the non-light emitting area. The reason why the surface roughness of the top surface 41a1_1 in the first light emitting area EA1 of the transparent layer 41_1 is greater than the surface roughness of the top surface 41a2 in the non-light emitting area may be due to Figure 13 This is caused by the over-etching that occurs in the third etching process described in . Figure 13 As described in the foregoing, the etchant used in the third etching has a good etching rate for the first protective layer PS1". In the third etching, the first protective layer PS1" is etched, but it is preferred that the second protective layer PS2 and the transparent layer 41_1 are not etched. However, the etching rate of the first protective layer PS1" to the etchant is approximately 100 times or more the etching rate of the second protective layer PS2 to the etchant, and even if over-etching occurs, the second protective layer PS2 is hardly etched. However, since the etching rate of the first protective layer PS1" to the etchant is approximately eight times or more the etching rate of the transparent layer 41_1 to the etchant, when over-etching occurs in the third etching, a portion of the top surface of the transparent layer 41_1 may be etched. Since the transparent layer 41_1 is covered by the second protective layer PS2 in the non-luminescent area, even if over-etching occurs in the third etching, the top surface 41a2 of the transparent layer 41_1 in the non-luminescent area will not be etched.

[0146] Because the above Figures 1 to 15 Other descriptions have been made in, so their detailed description will be omitted below.

[0147] Figure 17 is a cross-sectional view of a display device according to another embodiment.

[0148] Reference Figure 17 The display device 1_2 according to the embodiment and the display device 1_2 according to the embodiment Figure 2 and Figure 5 The display device 1 is different in that it includes a transparent layer 41_2.

[0149] The transparent layer 41_2 may include a first portion 41P1 disposed in the first emission area EA1 and a second portion 41P2 disposed in the non-emission area. A thickness t2 of the first portion 41P1 may be smaller than a thickness t1 of the second portion 41P2.

[0150] The reason why the thickness t2 of the first portion 41P1 is smaller than the thickness t1 of the second portion 41P2 may be due to Figure 13 This is caused by the over-etching that occurs in the third etching process described in . Figure 13As described in the third etching, the etchant used in the third etching has a good etching rate for the first protective layer PS1″. In the third etching, the first protective layer PS1″ is etched, but it is preferable that the second protective layer PS2 and the transparent layer 41 are not etched. However, the etching rate of the first protective layer PS1″ to the etchant is about 100 times or more than the etching rate of the second protective layer PS2 to the etchant, and even if overetching occurs, the second protective layer PS2 is hardly etched. However, since the etching rate of the first protective layer PS1″ to the etchant is about eight times or more than the etching rate of the transparent layer 41 to the etchant, when overetching occurs in the third etching, a portion of the top surface of the transparent layer 41 may be etched. Therefore, since the second portion 41P2 in the non-light-emitting area is covered by the second protective layer PS2, the first thickness t1 is maintained even if overetching occurs in the third etching. However, if the first portion 41P1 in the first light-emitting area EA1 is overetched, a portion of the first portion 41P1 is etched, and the first portion 41P1 may have a second thickness t2 that is smaller than the first thickness t1.

[0151] Because the above Figures 1 to 15 Other descriptions have been made in, so their detailed description will be omitted below.

[0152] Figure 18 is a cross-sectional view of a display device according to another embodiment.

[0153] Reference Figure 18 , the display device 1_3 according to the embodiment and the display device according to Figure 17 The difference between the display device 1_2 is that the first portion 41P1 (see Figure 17 ) includes a top surface 41a1_1 having surface irregularities (see Figure 16 ).

[0154] In more detail, the transparent layer 41_3 may include a first portion 41P1 disposed in the first emission area EA1 and a second portion 41P2 disposed in the non-emission area. A thickness t2 of the first portion 41P1 may be smaller than a thickness t1 of the second portion 41P2.

[0155] In addition, if Figure 16 In the embodiment, the top surface 41a1_1 of the first portion 41P1 may include surface irregularities. For example, the surface roughness of the top surface 41a1_1 of the first portion 41P1 may be greater than the surface roughness of the top surface 41a2 of the second portion 41P2 disposed in the non-emission region.

[0156] Because the above Figure 16 and Figure 17 Other descriptions have been made in, so their detailed description will be omitted below.

[0157] Figure 19 is a cross-sectional view of a display device according to another embodiment.

[0158] Reference Figure 19 , the display device 1_4 according to the embodiment and the display device according to Figure 2 and Figure 5 The display device 1 is different in that it may include a first protection layer PS1_1.

[0159] In more detail, the first protective layer PS1_1 may include a recessed portion IDP that is recessed from the first light-emitting area EA1 toward the non-light-emitting area. A side surface PS1c of the first protective layer PS1_1 may have a curved shape. Due to the recessed portion IDP, the bottom surface PS1a of the first protective layer PS1_1 may be positioned recessed from the first light-emitting area EA1 toward the non-light-emitting area, compared to the top surface PS1b of the first protective layer PS1_1. In other words, the end of the bottom surface PS1a may be positioned further away from the first light-emitting area EA1 than the end of the top surface PS1b.

[0160] Available through Figure 13 The recessed portion IDP is formed by over-etching that occurs in the third etching process described in

[0044] In the third etching process, the first protection layer PS1_1 may be over-etched by the etchant, thereby forming the recessed portion IDP.

[0161] although Figure 19 The end of the bottom surface PS1a is shown as being located farther away from the first light emitting area EA1 than the end of the top surface PS1b. However, the end of the bottom surface PS1a is not limited thereto, but may be located closer to the first light emitting area EA1 than the end of the top surface PS1b, or the end of the bottom surface PS1a and the end of the top surface PS1b may be located on the same line.

[0162] Because the above Figures 1 to 15 Other descriptions have been made in, so their detailed description will be omitted below.

[0163] Figure 20 is a cross-sectional view of a display device according to another embodiment.

[0164] Reference Figure 20 , the display device 1_5 according to the embodiment and the display device according to Figure 19 The difference of the display device 1_4 is that it includes Figure 16 The transparent layer 41_1 described in FIG.

[0165] In more detail, the top surface 41a1_1 in the first emission area EA1 of the transparent layer 41_1 may include surface irregularities. For example, the surface roughness of the surface 41a1_1 in the first emission area EA1 of the transparent layer 41_1 may be greater than the surface roughness of the top surface 41a2 in the non-emission area.

[0166] The first protective layer PS1_1 may include a recessed portion IDP recessed from the first light emitting area EA1 toward the non-light emitting area.

[0167] Because the above Figure 16 and Figure 19 Other descriptions have been made in, so their detailed description will be omitted below.

[0168] Figure 21 is a cross-sectional view of a display device according to another embodiment.

[0169] Reference Figure 21 , the display device 1_6 according to the embodiment and the display device according to Figure 19 The difference of the display device 1_4 is that it includes Figure 17 The transparent layer 41_2 described in FIG.

[0170] In more detail, the transparent layer 41_2 may include a first portion 41P1 disposed in the first emission area EA1 and a second portion 41P2 disposed in the non-emission area. A thickness t2 of the first portion 41P1 may be smaller than a thickness t1 of the second portion 41P2.

[0171] The first protective layer PS1_1 may include a recessed portion IDP recessed from the first light emitting area EA1 toward the non-light emitting area.

[0172] Because the above Figure 17 and Figure 19 Other descriptions have been made in, so their detailed description will be omitted below.

[0173] Figure 22 is a cross-sectional view of a display device according to another embodiment.

[0174] Reference Figure 22 , the display device 1_7 according to the embodiment and the display device according to Figure 19 The difference of the display device 1_4 is that it includes Figure 18 The transparent layer 41_3 described in FIG.

[0175] In more detail, the transparent layer 41_3 may include a first portion 41P1 disposed in the first emission area EA1 and a second portion 41P2 disposed in the non-emission area. A thickness t2 of the first portion 41P1 may be smaller than a thickness t1 of the second portion 41P2.

[0176] In addition, if Figure 16 In the embodiment, the top surface 41a1_1 of the first portion 41P1 may include surface irregularities. For example, the surface roughness of the top surface 41a1_1 of the first portion 41P1 may be greater than the surface roughness of the top surface 41a2 of the second portion 41P2 disposed in the non-emission region.

[0177] The first protective layer PS1_1 may include a recessed portion IDP recessed from the first light emitting area EA1 toward the non-light emitting area.

[0178] Because the above Figure 18 and Figure 19 Other descriptions have been made in, so their detailed description will be omitted below.

[0179] A display device according to various embodiments of the present disclosure can be described as follows.

[0180] A display device according to various embodiments of the present disclosure includes: a substrate including a plurality of sub-pixels; a transparent layer disposed in each of the plurality of sub-pixels; a first protective layer disposed on the transparent layer; and a second protective layer disposed on the first protective layer. The sub-pixels include a light-emitting region exposed by the transparent layer through the first and second protective layers, and a non-light-emitting region surrounding the light-emitting region.

[0181] In the display device according to various embodiments of the present disclosure, the first protection layer and the second protection layer may be disposed at a boundary between the light emitting region and the non-light emitting region.

[0182] The display device according to various embodiments of the present disclosure may further include an insulating layer disposed between the substrate and the transparent layer. In the non-emission region, the second protective layer may directly contact a top surface of the insulating layer and a side surface of the transparent layer.

[0183] The display device according to various embodiments of the present disclosure may further include a common light emitting layer disposed on the second protective layer and a second electrode disposed on the common light emitting layer.

[0184] The display device according to various embodiments of the present disclosure may further include a reflective electrode disposed between the substrate and the transparent layer.

[0185] In the display device according to various embodiments of the present disclosure, the reflective electrode may be electrically connected to the transparent layer. The display device may further include a transistor disposed between the substrate and the transparent layer. The transistor may be electrically connected to the reflective electrode.

[0186] In a display device according to various embodiments of the present disclosure, the subpixels may include a first subpixel, a second subpixel, and a third subpixel. The distance between the reflective electrode and the transparent layer in the first subpixel may be greater than the distance between the reflective electrode and the transparent layer in the second subpixel and the distance between the reflective electrode and the transparent layer in the third subpixel, respectively. The distance between the reflective electrode and the transparent layer in the second subpixel may be greater than the distance between the reflective electrode and the transparent layer in the third subpixel.

[0187] In the display device according to various embodiments of the present disclosure, the thickness of the transparent layer may be 5 nm or less.

[0188] In the display device according to various embodiments of the present disclosure, an etching rate of the second protective layer may be three times or more than an etching rate of the first protective layer and an etching rate of the transparent layer, respectively.

[0189] In the display device according to various embodiments of the present disclosure, an etching rate of the first protective layer may be five times or more than an etching rate of the second protective layer and an etching rate of the transparent layer, respectively.

[0190] In the display device according to various embodiments of the present disclosure, the surface roughness of the transparent layer in the light emitting region may be greater than the surface roughness of the transparent layer in the non-light emitting region.

[0191] In the display device according to various embodiments of the present disclosure, the thickness of the transparent layer in the light emitting region may be smaller than the thickness of the transparent layer in the non-light emitting region.

[0192] In the display device according to various embodiments of the present disclosure, the thickness of the transparent layer in the light emitting region may be smaller than the thickness of the transparent layer in the non-light emitting region.

[0193] In the display device according to various embodiments of the present disclosure, the first protective layer may include a bottom surface contacting the transparent layer and a top surface contacting the second protective layer. The bottom surface of the first protective layer may be recessed toward the non-emission region compared to the top surface.

[0194] According to various embodiments of the present disclosure, a manufacturing method of a display device may include the following steps: forming a transparent layer on a substrate, the substrate including sub-pixels, the sub-pixels having a light-emitting area and a non-light-emitting area around the light-emitting area; forming a first protective layer on the transparent layer; performing a first etching on the transparent layer and the first protective layer; forming a second protective layer on the first protective layer that has been etched by the first etching; performing a second etching on the second protective layer on the light-emitting area; and performing a third etching on the first protective layer on the light-emitting area.

[0195] In the method of manufacturing the display device according to various embodiments of the present disclosure, when performing the first etching, the transparent layer and the first protective layer may be etched using the first photoresist on the first protective layer.

[0196] The method for manufacturing a display device according to various embodiments of the present disclosure may further include removing the first photoresist between the first etching step and the second protective layer forming step. The removal of the first photoresist may be performed by oxygen plasma.

[0197] In the method of manufacturing the display device according to various embodiments of the present disclosure, when performing the second etching, the second protective layer may be etched by using the first photoresist on the second protective layer.

[0198] The method for manufacturing a display device according to various embodiments of the present disclosure may further include removing the first photoresist between the second etching step and the third etching step. The removal of the first photoresist may be performed using oxygen plasma.

[0199] In the method for manufacturing a display device according to various embodiments of the present disclosure, the etching rate of the second protective layer by the etching gas for the second etching may be three times or more than the etching rate of the first protective layer by the etching gas and the etching rate of the transparent layer by the etching gas. The etching rate of the first protective layer by the etching gas for the third etching may be five times or more than the etching rate of the second protective layer by the etching gas and the etching rate of the transparent layer by the etching gas.

[0200] The embodiments and implementations disclosed above are examples of the disclosed technology, and thus various enhancements and changes may be made to the disclosed embodiments and implementations and other embodiments and implementations based on the contents described and shown in this patent document to facilitate the implementation of the disclosed technology.

[0201] CROSS-REFERENCE TO RELATED APPLICATIONS

[0202] This patent document claims priority to Korean Patent Application No. 10-2024-0039475, filed on Mar. 22, 2024, which is hereby incorporated by reference in its entirety for all purposes.

Claims

1. A display device, comprising: substrate; a plurality of sub-pixels supported by the substrate and emitting light of different colors; a transparent layer, the transparent layer being disposed in the plurality of sub-pixels; a first protective layer, the first protective layer being disposed on the transparent layer; as well as a second protective layer, the second protective layer being arranged on the first protective layer; The sub-pixels in the plurality of sub-pixels include a light-emitting region that emits light and a non-light-emitting region surrounding the light-emitting region, and the first protective layer and the second protective layer expose the transparent layer.

2. The display device according to claim 1, wherein The first protective layer and the second protective layer are arranged to define a boundary between the light emitting area and the non-light emitting area.

3. The display device according to claim 2, further comprising an insulating layer provided between the substrate and the transparent layer, wherein In the non-light emitting region, the second protection layer directly contacts a top surface of the insulating layer and side surfaces of the transparent layer. 4 . The display device according to claim 1 , further comprising a common light emitting layer disposed on the second protective layer and a second electrode disposed on the common light emitting layer. 5 . The display device according to claim 1 , further comprising a reflective electrode disposed between the substrate and the transparent layer. The display device according to claim 5 , wherein: The reflective electrode is electrically connected to the transparent layer, wherein the display device further includes a transistor disposed between the substrate and the transparent layer, and wherein the transistor is electrically connected to the reflective electrode.

7. The display device according to claim 5, in, The plurality of sub-pixels include a first sub-pixel, a second sub-pixel, and a third sub-pixel, The distance between the reflective electrode and the transparent layer in the first sub-pixel is greater than the distance between the reflective electrode and the transparent layer in the second sub-pixel and the distance between the reflective electrode and the transparent layer in the third sub-pixel, and The distance between the reflective electrode and the transparent layer in the second sub-pixel is greater than the distance between the reflective electrode and the transparent layer in the third sub-pixel.

8. The display device according to claim 1, wherein The transparent layer has a thickness of 5 nm or less.

9. The display device according to claim 1, wherein An etching rate of the second protective layer is three times or more than an etching rate of the first protective layer and an etching rate of the transparent layer.

10. The display device according to claim 1, wherein An etching rate of the first protective layer is five times or more than an etching rate of the second protective layer and an etching rate of the transparent layer.

11. The display device according to claim 1, wherein The surface roughness of the transparent layer in the light emitting region is greater than the surface roughness of the transparent layer in the non-light emitting region.

12. The display device according to claim 1, wherein The thickness of the transparent layer in the light emitting region is smaller than the thickness of the transparent layer in the non-light emitting region.

13. The display device according to claim 1, wherein The first protection layer includes a concave portion facing the non-light emitting area.

14. The display device according to claim 13, wherein: The first protective layer includes a bottom surface contacting the transparent layer and a top surface contacting the second protective layer, and wherein the bottom surface of the first protective layer is recessed toward the non-light emitting region compared to the top surface of the first protective layer.

15. A method for manufacturing a display device, the method comprising the following steps: forming a transparent layer on a sub-pixel, the sub-pixel having a light-emitting region and a non-light-emitting region surrounding the light-emitting region; forming a first protective layer on the transparent layer; performing a first etching on the transparent layer and the first protective layer; forming a second protective layer on the first protective layer that has been subjected to the first etching; performing a second etching on the second protective layer in the light emitting region; as well as A third etching is performed on the first protective layer in the light emitting region.

16. The manufacturing method according to claim 15, wherein: The step of performing the first etching includes etching the transparent layer and the first protective layer using a first photoresist on the first protective layer.

17. The manufacturing method according to claim 16, further comprising the following steps: After performing the first etching and before providing the second protective layer, the first photoresist is removed using oxygen plasma.

18. The manufacturing method according to claim 15, wherein: The step of performing the second etching includes etching the second protective layer using the first photoresist on the second protective layer.

19. The manufacturing method according to claim 18, further comprising the following steps: After performing the second etch and before performing the third etch, the first photoresist is removed using oxygen plasma.

20. The manufacturing method according to claim 15, wherein The etching rate of the second protective layer to the etching gas of the second etching is three times or more the etching rate of the first protective layer to the etching gas and the etching rate of the transparent layer to the etching gas, and wherein the etching rate of the first protective layer to the etching gas of the third etching is five times or more the etching rate of the second protective layer to the etching gas and the etching rate of the transparent layer to the etching gas.

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