Display device and method for manufacturing a display device

Abstract

A display device and a manufacturing method of a display device are provided. The display device includes a substrate, a light emitting element disposed on the substrate, a cover layer covering the light emitting element, and an encapsulation layer disposed on the cover layer, the cover layer including a first inorganic layer, a first flexible layer disposed on the first inorganic layer and including silicon and carbon, and a second inorganic layer disposed on the first flexible layer, a thickness of the first flexible layer accounting for 80% or more of a thickness of the cover layer.

Description

Technical Field

[0001] This invention relates to a display device and a method for manufacturing a display device. Background Technology

[0002] The display device may include a light-emitting element that receives electrical signals and emits light. To improve the efficiency of the light emitted from the light-emitting element, the display device may include a cover layer disposed on the light-emitting element. Typically, the cover layer may include an organic material.

[0003] Because light-emitting elements are susceptible to the effects of impurities such as gases and moisture, their luminous efficiency may decrease due to impurities flowing into the display device from the outside. To prevent this decrease in luminous efficiency, an encapsulation layer can be formed on the light-emitting element to isolate it from the outside. The encapsulation layer may include an organic layer and inorganic layers disposed above and below the organic layer, respectively.

[0004] In recent years, display devices with deformable shapes, such as foldable or stretchable displays, have been realized. Therefore, if the structures of the encapsulation and cover layers are not simplified, the encapsulation and cover layers may be damaged due to the deformation of the display device. Summary of the Invention

[0005] One object of the present invention is to provide a display device including a cover layer and an encapsulation layer, wherein the cover layer and the encapsulation layer have a simple structure that can be applied to a foldable display device or a retractable display device.

[0006] Another object of the present invention is to provide a method for manufacturing a display device that improves process efficiency.

[0007] However, the purpose of this invention is not limited to the above-described purpose, and various extensions can be made without departing from the spirit and scope of this invention.

[0008] To achieve the aforementioned objective of the present invention, the display device according to various embodiments may include: a substrate; a light-emitting element disposed on the substrate; a cover layer covering the light-emitting element; and an encapsulation layer disposed on the cover layer, wherein the cover layer includes: a first inorganic layer; a first flexible layer disposed on the first inorganic layer and comprising silicon and carbon; and a second inorganic layer disposed on the first flexible layer, wherein the thickness of the first flexible layer is more than 80% of the thickness of the cover layer.

[0009] In one embodiment, the refractive index of the first inorganic layer, the refractive index of the first flexible layer, and the refractive index of the second inorganic layer may each be 1.75 or higher.

[0010] In one embodiment, the difference between the refractive index of the first inorganic layer and the refractive index of the first flexible layer may be less than 0.15, and the difference between the refractive index of the first flexible layer and the refractive index of the second inorganic layer may be less than 0.15.

[0011] In one embodiment, the refractive index of the first inorganic layer may be greater than that of the first flexible layer, and the refractive index of the second inorganic layer may be greater than that of the first flexible layer.

[0012] In one embodiment, the thickness of the covering layer may be 50 nm or more and 90 nm or less.

[0013] In one embodiment, the thickness of the first inorganic layer and the thickness of the second inorganic layer may be greater than 0.1 nm and less than 7.0 nm, respectively.

[0014] In one embodiment, the first inorganic layer and the second inorganic layer may each comprise SiN. x Furthermore, the first flexible layer comprises SiCN.

[0015] In one embodiment, the encapsulation layer may include an organic encapsulation layer and an inorganic encapsulation layer disposed on the organic encapsulation layer, and the lower surface of the organic encapsulation layer is in direct contact with the upper surface of the cover layer.

[0016] In one embodiment, the cover layer may further include: a second flexible layer disposed on the second inorganic layer and comprising silicon and carbon; and a third inorganic layer disposed on the second flexible layer, wherein the sum of the thickness of the first flexible layer and the thickness of the second flexible layer is more than 80% of the thickness of the cover layer.

[0017] In one embodiment, the thickness of the covering layer may be 50 nm or more and 90 nm or less.

[0018] In one embodiment, the difference between the refractive index of the first inorganic layer and the refractive index of the first flexible layer may be less than 0.15, the difference between the refractive index of the first flexible layer and the refractive index of the second inorganic layer may be less than 0.15, the difference between the refractive index of the second inorganic layer and the refractive index of the second flexible layer may be less than 0.15, and the difference between the refractive index of the second flexible layer and the refractive index of the third inorganic layer may be less than 0.15.

[0019] To achieve the other objectives of the present invention described above, the manufacturing method of the display device according to various embodiments may include: a step of forming a light-emitting element on a substrate; a step of forming a cover layer on the light-emitting element; and a step of forming an encapsulation layer on the cover layer, wherein the step of forming the cover layer includes: a step of forming a first inorganic layer; a step of forming a first flexible layer comprising silicon and carbon on the first inorganic layer; and a step of forming a second inorganic layer on the first flexible layer, wherein the thickness of the first flexible layer is 80% or more of the thickness of the cover layer.

[0020] In one embodiment, the steps of forming the first inorganic layer and forming the second inorganic layer may be performed by plasma-enhanced atomic layer deposition (PEALD) using polysilane, and the step of forming the first flexible layer may be performed by plasma-enhanced chemical vapor deposition (PECVD) using the polysilane.

[0021] In one embodiment, the step of forming the first inorganic layer may further include the step of adjusting the refractive index of the first inorganic layer, and the step of forming the second inorganic layer may further include the step of adjusting the refractive index of the second inorganic layer.

[0022] In one embodiment, the step of forming the first flexible layer may further include the step of adjusting the refractive index of the first flexible layer.

[0023] In one embodiment, the thickness of the covering layer may be 50 nm or more and 90 nm or less.

[0024] In one embodiment, the step of forming the cover layer may further include: forming a second flexible layer on the second inorganic layer; and forming a third inorganic layer on the second flexible layer, wherein the sum of the thickness of the first flexible layer and the thickness of the second flexible layer is more than 80% of the thickness of the cover layer.

[0025] In one embodiment, the step of forming the second flexible layer may be performed by plasma-enhanced chemical vapor deposition (PECVD) using polysilane, and the step of forming the third inorganic layer may be performed by plasma-enhanced atomic layer deposition (PEALD) using the polysilane.

[0026] In one embodiment, the thickness of the covering layer may be 50 nm or more and 90 nm or less.

[0027] In one embodiment, the step of forming the encapsulation layer may include: forming an organic encapsulation layer; and forming an inorganic encapsulation layer on the organic encapsulation layer, wherein the lower surface of the organic encapsulation layer is in direct contact with the upper surface of the cover layer.

[0028] (Invention Effects)

[0029] The display device may include a cover layer having a first inorganic layer, a first flexible layer, and a second inorganic layer, wherein the thickness of the first flexible layer may be more than 80% of the thickness of the cover layer. The display device may include an encapsulation layer disposed on the cover layer. Thus, a display device including a cover layer and an encapsulation layer can be provided, the cover layer and the encapsulation layer having a simple structure applicable to foldable or retractable display devices.

[0030] A method for manufacturing a display device may include the steps of forming a cover layer on a light-emitting element and forming an encapsulation layer on the cover layer. The step of forming the cover layer may include forming a first inorganic layer, forming a first flexible layer, and forming a second inorganic layer. Therefore, the structure of the cover layer and encapsulation layer included in the display device becomes simple, simplifying the steps of the display device manufacturing method.

[0031] However, the effects of the present invention are not limited to those described above, and various extensions can be made without departing from the spirit and scope of the present invention. Attached Figure Description

[0032] Figure 1 This is a diagram illustrating the stacked structure of a display device according to an embodiment of the present invention.

[0033] Figure 2 It is shown Figure 1 A diagram of a portion of a display device.

[0034] Figure 3 It is shown that... Figure 1 A graph showing the light efficiency related to the refractive index of the coating layer.

[0035] Figure 4 It is shown that... Figure 1 The table shows the light efficiency related to the thickness of the coating layer.

[0036] Figure 5 It is shown that... Figure 1 The table shows the WAD (white angular dependency) related to the thickness of the overlay.

[0037] Figure 6 It is shown Figure 1 Figures of other embodiments of the overlay layer.

[0038] Figure 7 This is a schematic cross-sectional view illustrating a display device according to an embodiment of the present invention.

[0039] Figures 8a to 8eThis is a diagram illustrating a method for manufacturing a display device according to an embodiment of the present invention.

[0040] Figure 9 This is a graph illustrating the non-uniformity of the coating layer manufactured by PEALD and / or PECVD methods.

[0041] Figure 10a and Figure 10b This is a diagram illustrating a method for manufacturing a cover layer according to an embodiment of the present invention.

[0042] Symbol explanation:

[0043] 100: Substrate; 200: Light-emitting element; 300, 300′: Cover layer; 301: First inorganic layer; 302: First flexible layer; 303: Second inorganic layer; 304: Second flexible layer; 305: Third inorganic layer; 400: Encapsulation layer; 401: Organic encapsulation layer; 402: Inorganic encapsulation layer; 1000: Display device. Detailed Implementation

[0044] Hereinafter, with reference to the accompanying drawings, the display device and the method of manufacturing the display device according to various embodiments of the present invention will be described in more detail. The same or similar reference numerals are used for the same constituent elements in the drawings.

[0045] Figure 1 This is a diagram illustrating the stacked structure of a display device according to an embodiment of the present invention.

[0046] Reference Figure 1 The display device 1000 may include a substrate 100, a light-emitting element 200, a cover layer 300, and an encapsulation layer 400.

[0047] The substrate 100 may include glass, quartz, plastic, polymer materials, etc. Preferably, the substrate 100 may be a flexible substrate including polyimide (PI).

[0048] The light-emitting element 200 may be disposed on the substrate 100. The light-emitting element 200 may include any structure capable of receiving an electrical signal and emitting light with a brightness corresponding to the electrical signal. For example, the light-emitting element 200 may include an organic light-emitting element (OLED), a quantum dot light-emitting element, etc. The luminous efficiency of the light-emitting element 200 may be reduced due to impurities such as gases and moisture.

[0049] The cover layer 300 can cover the light-emitting element 200. The cover layer 300 can improve the efficiency of light emitted from the light-emitting element 200. In addition, the cover layer 300 can isolate the light-emitting element 200 from impurities such as gas and moisture.

[0050] The cover layer 300 may include a first inorganic layer 301, a first flexible layer 302 disposed on the first inorganic layer 301, and a second inorganic layer 303 disposed on the first flexible layer 302.

[0051] The first inorganic layer 301 may include an inorganic material. For example, the first inorganic layer 301 may include SiN. x The first inorganic layer 301 serves as a seed layer for configuring the first flexible layer 302. Furthermore, the first inorganic layer 301 isolates the light-emitting element 200 from external impurities.

[0052] The first flexible layer 302 may include silicon and carbon. For example, the first flexible layer 302 may include SiCN. The ductility of the first flexible layer 302 may be greater than that of the first inorganic layer 301 and the second inorganic layer 303.

[0053] The second inorganic layer 303 may include an inorganic material. For example, the second inorganic layer 303 may include SiN. x The second inorganic layer 303 serves as a passivation layer. The second inorganic layer 303 prevents the first flexible layer 302 and the encapsulation layer 400 from direct contact. Furthermore, the second inorganic layer 303 isolates the light-emitting element 200 from external impurities.

[0054] The thickness of the first inorganic layer 301 can be a first thickness D1, and the refractive index of the first inorganic layer 301 can be a first refractive index n1. The thickness of the first flexible layer 302 can be a second thickness D2, and the refractive index of the first flexible layer 302 can be a second refractive index n2. The thickness of the second inorganic layer 303 can be a third thickness D3, and the refractive index of the second inorganic layer 303 can be a third refractive index n3. The thickness Dc of the capping layer 300 can be the value obtained by adding the first thickness D1 of the first inorganic layer 301, the second thickness D2 of the first flexible layer 302, and the third thickness D3 of the second inorganic layer 303.

[0055] The second thickness D2 can be about 80% or more of the thickness Dc of the cover layer 300. Preferably, the second thickness D2 can be about 90% or more and about 98% or less of the thickness Dc of the cover layer 300. Thus, even if the substrate 100 is folded or stretched, the cover layer 300 will not break.

[0056] The encapsulation layer 400 may be disposed on the cover layer 300. The encapsulation layer 400 may cover the cover layer 300. The encapsulation layer 400 may isolate the light-emitting element 200 from external impurities.

[0057] In one embodiment, the encapsulation layer 400 may include an organic encapsulation layer 401 and an inorganic encapsulation layer 402. The inorganic encapsulation layer 402 may be disposed on the organic encapsulation layer 401. The organic encapsulation layer 401 may include organic materials, and the inorganic encapsulation layer 402 may include inorganic materials. The inorganic encapsulation layer 402 may isolate the light-emitting element 200 from external impurities. The upper surface of the organic encapsulation layer 401 may be a flat surface. The refractive index of the organic encapsulation layer 401 may be more than about 1.4 and less than about 1.5.

[0058] The lower surface of the organic encapsulation layer 401 can be in direct contact with the upper surface of the cover layer 300. For example, the lower surface of the organic encapsulation layer 401 can be in direct contact with the upper surface of the second inorganic layer 303.

[0059] Figure 2 It is shown Figure 1 A diagram of a portion of a display device.

[0060] Reference Figure 2 The light-emitting element 200 emits light L. Light L can pass through the capping layer 300 and be incident on the interface between the capping layer 300 and the organic encapsulation layer 401. When the angle of incidence of light L at the interface between the capping layer 300 and the organic encapsulation layer 401 is greater than the critical angle θc, total internal reflection of light L can occur. That is, light L can be completely reflected at the interface between the organic encapsulation layer 401 and the capping layer 300.

[0061] The greater the difference between the refractive index nc of the capping layer 300 and the refractive index no of the organic encapsulation layer 401, the larger the critical angle θc can be. Specifically, the greater the refractive index nc of the capping layer 300 is than the refractive index no of the organic encapsulation layer 401, the greater the amount of light L′ that can be totally internalized.

[0062] The totally internalized light L′ can resonate with the light L emitted from the light-emitting element 200. As a result, the light efficiency can be increased.

[0063] In one embodiment, the refractive index nc of the capping layer 300 may be approximately 1.75 or higher. Specifically, the first refractive index n1 of the first inorganic layer 301, the second refractive index n2 of the first flexible layer 302, and the third refractive index n3 of the second inorganic layer 303 may each be approximately 1.75 or higher. Therefore, since more light L′ is totally internally reflected at the interface between the capping layer 300 and the organic encapsulation layer 401, the optical efficiency can be increased.

[0064] Figure 3 It is shown that... Figure 1 A graph showing the light efficiency related to the refractive index of the coating layer.

[0065] Reference Figure 3 , Figure 3 The graph shows the luminous efficiency of light passing through the 300mm overlay. Figure 3 In the chart, the luminous efficiency of red, green, blue, and white light in the comparative example ref is set to 100%, and the luminous efficiency of the first experimental example 31 and the second experimental example 32 for the comparative example ref are shown respectively. Figure 3 In the chart, the comparative example ref shows the light efficiency of light passing through an organic coating with a thickness of about 70 nm and a refractive index of about 1.9.

[0066] The experimental conditions for Experiment 31 are shown in Table 1 below.

[0067] [Table 1]

[0068] First Inorganic Layer 301 First flexible layer 302 Second inorganic layer 303 thickness 7nm 56nm 7nm Constituent matter <![CDATA[SiN x ]]> SiCN <![CDATA[SiN x ]]> Refractive index 1.9 1.75 1.9

[0069] The experimental conditions for Experiment 32 are shown in Table 2 below.

[0070] [Table 2]

[0071] First Inorganic Layer 301 First flexible layer 302 Second inorganic layer 303 thickness 7nm 56nm 7nm Constituent matter <![CDATA[SiN x ]]> SiCN <![CDATA[SiN x ]]> Refractive index 1.9 1.70 1.9

[0072] Referring to the first experimental example 31, when the difference between the first refractive index n1 of the first inorganic layer 301 and the second refractive index n2 of the first flexible layer 302 is approximately 0.15, and the difference between the third refractive index n3 of the second inorganic layer 303 and the second refractive index n2 of the first flexible layer 302 is approximately 0.15, the luminous efficiency of light passing through the capping layer 300 is the same as or higher than that of comparative example ref. Specifically, under the experimental conditions of the first experimental example 31, red light passing through the capping layer 300 exhibits a luminous efficiency of approximately 102%, and green, blue, and white light passing through the capping layer 300 each exhibit a luminous efficiency of approximately 100%.

[0073] Referring to Experimental Example 32, when the difference between the first refractive index n1 of the first inorganic layer 301 and the second refractive index n2 of the first flexible layer 302 is approximately 0.2, and the difference between the third refractive index n3 of the second inorganic layer 303 and the second refractive index n2 of the first flexible layer 302 is approximately 0.2, the luminous efficiency of light passing through the capping layer 300 can be lower than that of Comparative Example ref. Specifically, under the experimental conditions of Experimental Example 32, red light passing through the capping layer 300 exhibits approximately 96% luminous efficiency, green light passing through the capping layer 300 exhibits approximately 99% luminous efficiency, blue light passing through the capping layer 300 exhibits approximately 98% luminous efficiency, and white light passing through the capping layer 300 exhibits approximately 94% luminous efficiency.

[0074] In one embodiment, the difference between the first refractive index n1 of the first inorganic layer 301 and the second refractive index n2 of the first flexible layer 302 may be about 0.15 or less, and the difference between the third refractive index n3 of the second inorganic layer 303 and the second refractive index n2 of the first flexible layer 302 may be about 0.15 or less. Furthermore, the first refractive index n1 of the first inorganic layer 301 may be greater than the second refractive index n2 of the first flexible layer 302, and the third refractive index n3 of the second inorganic layer 303 may be greater than the second refractive index n2 of the first flexible layer 302. Therefore, the light efficiency of the capping layer 300 of the present invention may be equal to or higher than the light efficiency of an organic capping layer having the same thickness Dc as the capping layer 300.

[0075] Figure 4 It is shown that... Figure 1 The table shows the light efficiency related to the thickness of the coating layer. Figure 5 It is shown that... Figure 1 The table shows the WAD (white angular dependency) related to the thickness of the overlay.

[0076] Reference Figure 4 ,exist Figure 4 In the table, the luminous efficacy of red, green, blue, and white light for Comparative Example REF. is set to 100%, and the luminous efficacy of the capping layer 300 for Comparative Example REF. is shown in contrast. Comparative Example REF. can be the luminous efficacy of light passing through an organic capping layer with a thickness of approximately 82 nm.

[0077] With a thickness Dc of approximately 40 nm for the capping layer 300, the luminous efficiency of red light passing through the capping layer 300 is approximately 90%, the luminous efficiency of green light passing through the capping layer 300 is approximately 89.6%, the luminous efficiency of blue light passing through the capping layer 300 is approximately 100.4%, and the luminous efficiency of white light passing through the capping layer 300 is approximately 89.0%.

[0078] When the thickness Dc of the cladding layer 300 is less than approximately 40 nm, the light efficiency of light passing through the cladding layer 300 can be lower than when the thickness Dc of the cladding layer 300 is approximately 40 nm. That is, the smaller the thickness Dc of the cladding layer 300 is than approximately 40 nm, the lower the light efficiency of light passing through the cladding layer 300 can be.

[0079] With a thickness Dc of approximately 50 nm for the capping layer 300, the luminous efficiency of red light passing through the capping layer 300 is approximately 93.1%, the luminous efficiency of green light passing through the capping layer 300 is approximately 93.1%, the luminous efficiency of blue light passing through the capping layer 300 is approximately 105.8%, and the luminous efficiency of white light passing through the capping layer 300 is approximately 92.7%.

[0080] When the thickness Dc of the cladding layer 300 exceeds approximately 50 nm, the light efficiency passing through the cladding layer 300 is greater than when the thickness Dc of the cladding layer 300 is approximately 50 nm. That is, the greater the thickness of the cladding layer 300 is than approximately 50 nm, the higher the light efficiency passing through the cladding layer 300 can be.

[0081] Reference Figure 5 , Figure 5 It is shown that... Figure 1 The table shows the WAD (Wide Aspect Ratio) related to the thickness Dc of the cover layer 300. When white light is emitted from the light-emitting element 200, although the white light can be perceived from the front, blue light or other light may be perceived from the side instead of white light. WAD indicates the degree to which blue light or other light is perceived from the side of the light-emitting element 200 emitting white light.

[0082] When the thickness Dc of the cover layer 300 is about 100 nm, the WAD at approximately 45° can be about 0.030. As a result, blue light, green light, or red light, rather than white light, may be perceived from the side of the display device 1000.

[0083] Reference Figure 4 and Figure 5 In one embodiment, the thickness Dc of the capping layer 300 can be about 50 nm or more and about 90 nm or less. When the thickness Dc of the capping layer 300 is about 50 nm or more and about 90 nm or less, the first thickness D1 of the first inorganic layer 301 can be about 0.1 nm or more and about 7.0 nm or less, and the third thickness D3 of the second inorganic layer 303 can be about 0.1 nm or more and about 7.0 nm or less. When the thickness Dc of the capping layer 300 is 50 nm or more, the light efficiency of light passing through the capping layer 300 can be about 90% or more. When the thickness Dc of the capping layer 300 is about 90 nm or less, the light absorption angle (WAD) at angles of about 0° or more and about 45° or less can be less than about 0.3. Therefore, when the thickness Dc of the capping layer 300 is about 50 nm or more and about 90 nm or less, the light efficiency of light passing through the capping layer 300 can be about 90% or more, and the WAD at angles of about 0° or more and about 45° can be less than about 0.3.

[0084] Figure 6 It is shown Figure 1 Figures of other embodiments of the overlay layer.

[0085] Reference Figure 6The cover layer 300' may include a first inorganic layer 301, a first flexible layer 302 disposed on the first inorganic layer 301, a second inorganic layer 303 disposed on the first flexible layer 302, a second flexible layer 304 disposed on the second inorganic layer 303, and a third inorganic layer 305 disposed on the second flexible layer 304.

[0086] The first inorganic layer 301, the second inorganic layer 303, and the third inorganic layer 305 may each comprise an inorganic material. For example, the first inorganic layer 301, the second inorganic layer 303, and the third inorganic layer 305 may each comprise SiN. x .

[0087] The first flexible layer 302 and the second flexible layer 304 may respectively comprise carbon and silicon. For example, the first flexible layer 302 and the second flexible layer 304 may respectively comprise SiCN.

[0088] The thickness of the first inorganic layer 301 can be a first thickness D1, and the refractive index of the first inorganic layer 301 can be a first refractive index n1. The thickness of the first flexible layer 302 can be a second thickness D2, and the refractive index of the first flexible layer 302 can be a second refractive index n2. The thickness of the second inorganic layer 303 can be a third thickness D3, and the refractive index of the second inorganic layer 303 can be a third refractive index n3. The thickness of the second flexible layer 304 can be a fourth thickness D4, and the refractive index of the second flexible layer 304 can be a fourth refractive index n4. The thickness of the third inorganic layer 305 can be a fifth thickness D5, and the refractive index of the third inorganic layer 305 can be a fifth refractive index n5. The thickness Dc′ of the capping layer 300′ can be the value obtained by adding the first thickness D1, the second thickness D2, the third thickness D3, the fourth thickness D4, and the fifth thickness D5.

[0089] The sum of the second thickness D2 and the fourth thickness D4 relative to the thickness Dc′ of the cover layer 300′ can be more than about 80% of it. Preferably, the sum of the second thickness D2 and the fourth thickness D4 relative to the thickness Dc′ of the cover layer 300′ can be more than about 90% and less than about 98% of it.

[0090] The thickness Dc′ of the capping layer 300′ can be approximately 50 nm or more and approximately 90 nm or less. When the thickness Dc′ of the capping layer 300′ is approximately 50 nm or more and approximately 90 nm or less, the capping layer 300′ can have relatively high optical efficiency. Furthermore, when the thickness Dc′ of the capping layer 300′ is approximately 50 nm or more and approximately 90 nm or less, the capping layer 300′ can have relatively low light absorption (WAD).

[0091] The difference between the first refractive index n1 and the second refractive index n2 can be less than 0.15, the difference between the second refractive index n2 and the third refractive index n3 can be less than 0.15, the difference between the third refractive index n3 and the fourth refractive index n4 can be less than 0.15, and the difference between the fourth refractive index n4 and the fifth refractive index n5 can be less than 0.15. The first refractive index n1 can be greater than the second refractive index n2, the second refractive index n2 can be less than the third refractive index n3, the third refractive index n3 can be greater than the fourth refractive index n4, and the fourth refractive index n4 can be less than the fifth refractive index n5. Therefore, the optical efficiency of the capping layer 300′ can be equal to or higher than the optical efficiency of an organic capping layer having the same thickness Dc′ as the capping layer 300′.

[0092] Figure 7 This is a schematic cross-sectional view illustrating a display device according to an embodiment of the present invention.

[0093] Reference Figure 7 The display device 1000 may include a substrate 100, a transistor TR, a first insulating layer IL1, a second insulating layer IL2, a third insulating layer IL3, a pixel definition film PDL, an anode AE, a light-emitting layer EL, a cathode CE, a cover layer 300, and an encapsulation layer 400. The transistor TR may include an active layer ATV, a first electrode EL1, a second electrode EL2, and a gate electrode G.

[0094] The substrate 100 may include a base substrate 101 and a buffer layer 102 disposed on the base substrate 101. The base substrate 101 may include glass, plastic, polymer materials, etc. The base substrate 101 may be a flexible substrate including polyimide (PI). The buffer layer 102 can block impurities such as oxygen and moisture present in the base substrate 101. The buffer layer 102 may include inorganic insulating materials such as silicon oxide, silicon nitride, and silicon oxide nitride.

[0095] An active layer ATV can be configured on the buffer layer 102. The active layer ATV can be formed of polycrystalline silicon, amorphous silicon, or oxide semiconductor, etc.

[0096] A first insulating layer IL1 may be disposed on the active layer ATV. The first insulating layer IL1 may cover the active layer ATV and is disposed on the buffer layer 102. The first insulating layer IL1 may insulate the gate electrode G disposed on the active layer ATV from the active layer ATV.

[0097] A gate electrode G may be disposed on the first insulating layer IL1. The gate electrode G may include a conductive material.

[0098] A second insulating layer IL2 may be disposed on the gate electrode G. The second insulating layer IL2 may cover the gate electrode G and is disposed on the first insulating layer IL1. The second insulating layer IL2 may insulate the first electrode EL1 and the second electrode EL2 disposed on the gate electrode G from the gate electrode G.

[0099] A first electrode EL1 and a second electrode EL2 may be disposed on the second insulating layer IL2. The first electrode EL1 and the second electrode EL2 may be electrically connected to the active layer ATV. For example, the first electrode EL1 may contact one side of the active layer ATV through contact holes formed in the first insulating layer IL1 and the second insulating layer IL2. For example, the second electrode EL2 may contact the other side of the active layer ATV through contact holes formed in the first insulating layer IL1 and the second insulating layer IL2.

[0100] A third insulating layer IL3 may be disposed on the first electrode EL1 and the second electrode EL2. The third insulating layer IL3 may cover the first electrode EL1 and the second electrode EL2 and be disposed on the second insulating layer IL2. The upper surface of the third insulating layer IL3 may be flat.

[0101] An anode AE ​​may be disposed on the third insulating layer IL3. The anode AE ​​may comprise a conductive material. The anode AE ​​may be electrically connected to the first electrode EL1. For example, the anode AE ​​may contact one side of the first electrode EL1 through a contact hole formed in the third insulating layer IL3.

[0102] A pixel definition film (PDL) may be disposed on the anode AE. The PDL may cover a portion of the anode AE ​​and be disposed on a third insulating layer IL3. The PDL may have pixel openings that expose at least a portion of the anode AE. For example, the pixel openings may expose the central portion of the anode AE, and the PDL may cover the peripheral portion of the anode AE.

[0103] A light-emitting layer EL can be disposed on the anode AE. The light-emitting layer EL can be disposed on the anode AE ​​exposed through the pixel opening. The light-emitting layer EL may include organic light-emitting materials, quantum dot light-emitting materials, etc. The light-emitting layer EL can receive electrical signal input from the transistor TR through the anode AE. The light-emitting layer EL can emit light with a brightness corresponding to the intensity of the electrical signal.

[0104] A cathode (CE) can be configured on the light-emitting layer (EL). The cathode (CE) can also be configured on the pixel-defining film (PDL).

[0105] A capping layer 300 can be disposed on the cathode CE. The capping layer 300 covers the cathode CE. The capping layer 300 can increase the efficiency of light emitted from the light-emitting layer EL. The capping layer 300 can block external impurities such as gases and moisture. The capping layer 300 can be used with a reference... Figures 1 to 5 The description refers to the overlay 300 or reference. Figure 6 The described overlay 300′ is essentially the same.

[0106] An encapsulation layer 400 may be disposed on the cover layer 300. The encapsulation layer 400 may include an organic encapsulation layer 401 and an inorganic encapsulation layer 402 disposed on the organic encapsulation layer 401. The upper surface of the organic encapsulation layer 401 may be a flat surface. The organic encapsulation layer 401 may provide a flat surface for the inorganic encapsulation layer 402. The inorganic encapsulation layer 402 may block external impurities such as gases and moisture.

[0107] Figures 8a to 8e This is a diagram illustrating a method for manufacturing a display device according to an embodiment of the present invention.

[0108] Reference Figure 8a A light-emitting element 200 can be formed on a substrate 100. The substrate 100 may include glass, plastic, polymer materials, etc. The substrate 100 may be a flexible substrate including polyimide (PI). The light-emitting element 200 may include all structures capable of receiving electrical signals and emitting light with a brightness having an intensity corresponding to the electrical signal. For example, the light-emitting element 200 may include... Figure 7 The transistor TR, first insulating layer IL1, second insulating layer IL2, third insulating layer IL3, pixel definition film PDL, anode AE, light-emitting layer EL and cathode CE.

[0109] Reference Figure 8b A first inorganic layer 301 may be formed on the light-emitting element 200. The first inorganic layer 301 may cover the light-emitting element 200. The thickness of the first inorganic layer 301 may be a first thickness D1, and the refractive index of the first inorganic layer 301 may be a first refractive index n1. The first inorganic layer 301 may include SiN. x The first inorganic layer 301 can be formed by performing plasma-enhanced atomic layer deposition (PEALD) using polysilane.

[0110] In one embodiment, the first inorganic layer 301 can be formed by a PEALD process using BTBAS. For example, the step of forming the first inorganic layer 301 as a cycle may include: supplying BTBAS to a cavity (not shown) to form a silicon film by a PEALD process; injecting argon gas to purge the BTBAS residues and impurities; and supplying NH3 or N2 to the cavity to form SiN by a PEALD process. x The steps of membrane preparation; and the steps of injecting argon gas to remove the NH3 residue, the N2 residue and impurities.

[0111] As the cycle is repeated multiple times, the first thickness D1 can be increased. For example, in the case of repeating the cycle once, the first thickness D1 can be more than about 0.08 nm and less than about 1.3 nm. In the case of repeating the cycle five times, the first thickness D1 can be more than about 0.4 nm and less than about 6.5 nm.

[0112] The first refractive index n1 can vary depending on the plasma power in the PEALD. For example, when the plasma power is about 50 W, the first refractive index n1 can be about 1.95. When the plasma power is about 200 W, the first refractive index n1 can be about 2.05. When the plasma power is about 300 W, the first refractive index n1 can be about 1.9.

[0113] In one embodiment of the present invention, the step of forming the first inorganic layer 301 may further include adjusting the first refractive index n1. For example, the first refractive index n1 may be adjusted by adjusting the plasma intensity within the cycle.

[0114] Reference Figure 8c A first flexible layer 302 may be formed on the first inorganic layer 301. The first flexible layer 302 may cover the first inorganic layer 301 and the light-emitting element 200. The thickness of the first flexible layer 302 may be a second thickness D2, and the refractive index of the first flexible layer 302 may be a second refractive index n2. The first flexible layer 302 may include silicon and carbon. The first flexible layer 302 may include SiCN. The first flexible layer 302 may be formed by performing plasma-enhanced chemical vapor deposition (PECVD) using polysilane.

[0115] In one embodiment, the first flexible layer 302 can be formed by PECVD using BTBAS. For example, the step of forming the first flexible layer 302 may include supplying BTBAS, H2 and NH3 to a cavity (not shown) to form the first flexible layer 302 by PECVD.

[0116] By increasing the PECVD process time, the second thickness D2 can be increased. For example, when the process time is about 1 minute, the second thickness D2 can be about 18 nm or more and about 41 nm or less. When the process time is about 3 minutes, the second thickness D2 can be about 54 nm or more and about 123 nm or less.

[0117] The second refractive index n2 can vary depending on the plasma power in PECVD. For example, when the plasma power is about 35 W, the second refractive index n2 can be about 2. When the plasma power is about 50 W, the second refractive index n2 can be about 1.7. When the plasma power is about 100 W, the second refractive index n2 can be about 1.9.

[0118] In one embodiment of the invention, the step of forming the first flexible layer 302 may further include adjusting the second refractive index n2. For example, the second refractive index n2 may be adjusted by adjusting the plasma intensity in PECVD.

[0119] Reference Figure 8d A second inorganic layer 303 can be formed on the first flexible layer 302. The second inorganic layer 303 can cover the first flexible layer 302, the first inorganic layer 301, and the light-emitting element 200. The thickness of the second inorganic layer 303 can be a third thickness D3, and the refractive index of the second inorganic layer 303 can be a third refractive index n3. The second inorganic layer 303 may include SiN. x The second inorganic layer 303 can be formed by performing plasma-enhanced atomic layer deposition (PEALD) using polysilane.

[0120] In one embodiment of the present invention, the second inorganic layer 303 can be formed by a PEALD process using BTBAS. For example, the step of forming the second inorganic layer 303 as a cycle may include: supplying BTBAS to a cavity (not shown) to form a silicon film by a PEALD process; injecting argon gas to purge the BTBAS residues and impurities; and supplying NH3 or N2 to the cavity to form SiN by a PEALD process. x The steps of membrane preparation; and the steps of injecting argon gas to remove the NH3 residue, the N2 residue and impurities.

[0121] The third thickness D3 can be increased by repeating the cycle multiple times. The third refractive index n3 can become different by varying the plasma power of PEALD within the cycle. In one embodiment, the step of forming the second inorganic layer 303 may further include adjusting the third refractive index n3.

[0122] Reference Figure 8eAn encapsulation layer 400 can be formed on the cover layer 300. The step of forming the encapsulation layer 400 may include forming an organic encapsulation layer 401 on the cover layer 300 and forming an inorganic encapsulation layer 402 on the organic encapsulation layer 401. In the step of forming the organic encapsulation layer 401, the lower surface of the organic encapsulation layer 401 may be in direct contact with the upper surface of the cover layer 300. For example, the lower surface of the organic encapsulation layer 401 may be in direct contact with the upper surface of the second inorganic layer 303. The organic encapsulation layer 401 may be in contact with a reference... Figures 1 to 7 The organic encapsulation layer 401 described herein is substantially the same. The inorganic encapsulation layer 402 may be referenced. Figures 1 to 7 The inorganic encapsulation layer 402 described is essentially the same.

[0123] Refer again Figures 8b to 8e A cover layer 300 can be formed on the light-emitting element 200. The steps of forming the cover layer 300 may include forming a first inorganic layer 301 on the light-emitting element 200, forming a first flexible layer 302 on the first inorganic layer 301, and forming a second inorganic layer 303 on the first flexible layer 302. The cover layer 300 can cover the light-emitting element 200. The thickness Dc of the cover layer 300 can be the sum of the first thickness D1, the second thickness D2, and the third thickness D3. The second thickness D2 can be about 80% or more of the thickness Dc of the cover layer 300. Preferably, the second thickness D2 can be about 90% or more and about 98% or less of the thickness Dc of the cover layer 300.

[0124] In one embodiment of the present invention, the thickness Dc of the capping layer 300 can be 50 nm or more and 90 nm or less. Therefore, the capping layer 300 of the present invention can have relatively high light efficiency and relatively low light absorption (WAD).

[0125] Figure 9 This is a graph illustrating the non-uniformity of the coating layer manufactured by PEALD and / or PECVD methods.

[0126] Reference Figure 9 The capping layer manufactured by PEALD can have a non-uniformity of approximately 3.80%, while the capping layer manufactured by PECVD can have a non-uniformity of approximately 10.00%. The non-uniformity of the capping layer manufactured by PEALD can be lower than that of the capping layer manufactured by PECVD. That is, the upper surface of the capping layer manufactured by PEALD can be flatter than that of the capping layer manufactured by PECVD. However, the yield of PEALD may be lower than that of PECVD.

[0127] When a seed layer is formed by PEALD and a capping layer is formed on the seed layer by PECVD, the capping layer formed by PEALD and PECVD can have a non-uniformity of approximately 4.70%. In this case, the process time required to form the capping layer can be relatively reduced.

[0128] In one embodiment of the present invention, the first inorganic layer 301 can be formed by PEALD, the first flexible layer 302 can be formed by PECVD, and the second inorganic layer 303 can be formed by PEALD. Therefore, the process time required to form the capping layer 300 of the present invention can be relatively reduced, and the capping layer 300 of the present invention can have relatively low non-uniformity.

[0129] Figure 10a and Figure 10b This is a diagram illustrating a method for manufacturing a cover layer according to other embodiments of the present invention.

[0130] Reference Figure 10a A first inorganic layer 301 can be formed on the light-emitting element 200, a first flexible layer 302 can be formed on the first inorganic layer 301, a second inorganic layer 303 can be formed on the first flexible layer 302, and a second flexible layer 304 can be formed on the second inorganic layer 303. The steps for forming the first inorganic layer 301, the first flexible layer 302, and the second inorganic layer 303 can be referenced. Figures 8b to 8d The steps described are essentially the same.

[0131] The second flexible layer 304 may cover the second inorganic layer 303, the first flexible layer 302, the first inorganic layer 301, and the light-emitting element 200. The thickness of the second flexible layer 304 may be a fourth thickness D4, and the refractive index of the second flexible layer 304 may be a fourth refractive index n4. The second flexible layer 304 may include silicon and carbon. The second flexible layer 304 may include SiCN. The second flexible layer 304 may be formed by performing plasma chemical vapor deposition (PECVD) using polysilane. The step of forming the second flexible layer 304 may include forming the second flexible layer 304 by PECVD using BTBAS. The fourth thickness D4 and the fourth refractive index n4 may be adjusted by adjusting the process conditions of the PECVD process.

[0132] Reference Figure 10bA third inorganic layer 305 can be formed on the second flexible layer 304. The third inorganic layer 305 can cover the second flexible layer 304, the second inorganic layer 303, the first flexible layer 302, the first inorganic layer 301, and the light-emitting element 200. The thickness of the third inorganic layer 305 can be a fifth thickness D5, and the refractive index of the third inorganic layer 305 can be a fifth refractive index n5. The third inorganic layer 305 can be formed by performing plasma-enhanced atomic layer deposition (PEALD) using polysilane. The step of forming the third inorganic layer 305 may include forming the third inorganic layer 305 by PEALD using BTBAS. The fifth thickness D5 and the fifth refractive index n5 of the third inorganic layer 305 can be adjusted by adjusting the process conditions of the PEALD process.

[0133] The thickness Dc of the cover layer 300 can be the sum of the first thickness D1, the second thickness D2, the third thickness D3, the fourth thickness D4, and the fifth thickness D5. The sum of the second thickness D2 and the fourth thickness D4 can be approximately 80% or more of the thickness Dc of the cover layer 300. Preferably, the sum of the second thickness D2 of the first flexible layer 302 and the fourth thickness D4 of the second flexible layer 304 can be approximately 90% or more and approximately 98% or less of the thickness Dc of the cover layer 300.

[0134] In one embodiment of the present invention, the thickness Dc of the capping layer 300 can be 50 nm or more and 90 nm or less. Therefore, the capping layer 300 of the present invention can have relatively high light efficiency and relatively low light absorption (WAD).

[0135] (Industry availability)

[0136] The exemplary embodiments of the present invention relate to display devices and methods of manufacturing display devices that are applicable to display devices including computers, laptops, smartphones, smart tablets, etc.

[0137] The above description, with reference to the accompanying drawings, illustrates exemplary embodiments of the display device and a method for manufacturing the display device. However, the embodiments described are illustrative, and modifications and alterations can be made by those skilled in the art without departing from the scope of the technical concept of the invention as set forth in the claims.

Claims

1. A display device, characterized in that, include: substrate; Light-emitting elements are disposed on the substrate; A cover layer is applied to cover the light-emitting element. as well as An encapsulation layer is disposed on the cover layer. The covering layer includes: First inorganic layer; A first flexible layer, disposed on the first inorganic layer and comprising silicon and carbon; and The second inorganic layer is disposed on the first flexible layer. The thickness of the first flexible layer accounts for more than 80% of the thickness of the cover layer.

2. The display device according to claim 1, characterized in that, The refractive indices of the first inorganic layer, the first flexible layer, and the second inorganic layer are all greater than 1.

75.

3. The display device according to claim 1, characterized in that, The difference between the refractive index of the first inorganic layer and the refractive index of the first flexible layer is less than 0.

15. The difference between the refractive index of the first flexible layer and the refractive index of the second inorganic layer is less than 0.

15.

4. The display device according to claim 3, characterized in that, The refractive index of the first inorganic layer is greater than that of the first flexible layer. The refractive index of the second inorganic layer is greater than that of the first flexible layer.

5. The display device according to claim 1, characterized in that, The thickness of the covering layer is greater than 50 nm and less than 90 nm.

6. The display device according to claim 5, characterized in that, The thickness of the first inorganic layer and the thickness of the second inorganic layer are respectively greater than 0.1 nm and less than 7.0 nm.

7. The display device according to claim 1, characterized in that, The first inorganic layer and the second inorganic layer each comprise SiN x , The first flexible layer comprises SiCN.

8. The display device according to claim 1, characterized in that, The encapsulation layer includes an organic encapsulation layer and an inorganic encapsulation layer disposed on the organic encapsulation layer. The lower surface of the organic encapsulation layer is in direct contact with the upper surface of the cover layer.

9. The display device according to claim 1, characterized in that, The covering layer also includes: A second flexible layer, disposed on the second inorganic layer and comprising silicon and carbon; and The third inorganic layer is disposed on the second flexible layer. The sum of the thickness of the first flexible layer and the thickness of the second flexible layer accounts for more than 80% of the thickness of the cover layer.

10. The display device according to claim 9, characterized in that, The thickness of the covering layer is greater than 50 nm and less than 90 nm.

11. The display device according to claim 9, characterized in that, The difference between the refractive index of the first inorganic layer and the refractive index of the first flexible layer is less than 0.

15. The difference between the refractive index of the first flexible layer and the refractive index of the second inorganic layer is less than 0.

15. The difference between the refractive index of the second inorganic layer and the refractive index of the second flexible layer is less than 0.

15. The difference between the refractive index of the second flexible layer and the refractive index of the third inorganic layer is less than 0.

15.

12. A method for manufacturing a display device, comprising: The step of forming a light-emitting element on a substrate; The step of forming a cover layer on the light-emitting element; as well as The step of forming an encapsulation layer on the cover layer, The steps for forming the cover layer include: The steps to form the first inorganic layer; The step of forming a first flexible layer comprising silicon and carbon on the first inorganic layer; and The step of forming a second inorganic layer on the first flexible layer. The thickness of the first flexible layer accounts for more than 80% of the thickness of the cover layer.

13. The method for manufacturing a display device according to claim 12, characterized in that, The steps of forming the first inorganic layer and forming the second inorganic layer are performed using plasma-enhanced atomic layer deposition with polysilane. The step of forming the first flexible layer is performed using plasma-enhanced chemical vapor deposition of the polysilane.

14. The method for manufacturing a display device according to claim 13, characterized in that, The step of forming the first inorganic layer also includes the step of adjusting the refractive index of the first inorganic layer. The step of forming the second inorganic layer also includes adjusting the refractive index of the second inorganic layer.

15. The method for manufacturing a display device according to claim 13, characterized in that, The step of forming the first flexible layer also includes adjusting the refractive index of the first flexible layer.

16. The method for manufacturing a display device according to claim 12, characterized in that, The thickness of the covering layer is greater than 50 nm and less than 90 nm.

17. The method for manufacturing a display device according to claim 12, characterized in that, The step of forming the cover layer further includes: The step of forming a second flexible layer on the second inorganic layer; and The step of forming a third inorganic layer on the second flexible layer The sum of the thickness of the first flexible layer and the thickness of the second flexible layer accounts for more than 80% of the thickness of the cover layer.

18. The method for manufacturing a display device according to claim 17, characterized in that, The step of forming the second flexible layer is performed using plasma-enhanced chemical vapor deposition of polysilane. The step of forming the third inorganic layer is performed using plasma-enhanced atomic layer deposition of the polysilane.

19. The method for manufacturing a display device according to claim 17, characterized in that, The thickness of the covering layer is greater than 50 nm and less than 90 nm.

20. The method for manufacturing a display device according to claim 12, characterized in that, The steps for forming the encapsulation layer include: The steps for forming the organic encapsulation layer; and The step of forming an inorganic encapsulation layer on the organic encapsulation layer. The lower surface of the organic encapsulation layer is in direct contact with the upper surface of the cover layer.

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