protective layer for OLED subpixels

Abstract

The embodiments described herein relate to subpixels. In one or more embodiments, the subpixel comprises a substrate and overhang structures. The overhang structures comprise an extension disposed over the sidewalls of the overhang structures. The subpixel further comprises an anode disposed on the substrate, an inorganic layer disposed below each extension of the overhang structures, and an organic light-emitting diode (OLED) material disposed on the anode. The OLED material is disposed between the inorganic layers below each extension of the overhang structures. The subpixel further comprises a cathode disposed on the OLED material.

Description

Technology Field

[0001] The embodiments described herein generally relate to displays. More specifically, the embodiments described herein relate to a subpixel circuit and a method for forming the subpixel circuit that can be used in a display such as an organic light-emitting diode (OLED) display. Background Technology

[0002] Input devices, including display devices, can be used in various electronic systems. An organic light-emitting diode (OLED) is a light-emitting diode (LED) in which an emitting electroluminescent layer is a film of organic compound that emits light in response to an electric current. OLED devices are classified as bottom-emitting devices if the emitted light passes through a transparent or translucent bottom electrode and a substrate on which a panel is manufactured. Top-emitting devices are classified based on whether the light emitted from the OLED device is emitted through a cover added subsequently during the manufacturing of the device. OLEDs are used today to create display devices in many electronic devices. Today's electronics manufacturers are seeking to reduce the size of these display devices while providing higher resolutions than just a few years ago.

[0003] Therefore, there is a need for subpixel circuits and methods for forming subpixel circuits. means of solving the problem

[0004] The embodiments of the present disclosure relate to subpixel circuits, OLED subpixels, and related components and methods for manufacturing OLED subpixels.

[0005] In one or more embodiments, the subpixel comprises a substrate and overhang structures. The overhang structures include extensions disposed over the sidewalls of the overhang structures. The subpixel further comprises an anode disposed on the substrate, an inorganic layer disposed below each extension of the overhang structures, and an organic light-emitting diode (OLED) material disposed on the anode. The OLED material is disposed between the inorganic layers below each extension of the overhang structures. The subpixel further comprises a cathode disposed on the OLED material.

[0006] In one or more embodiments, the subpixel comprises overhang structures disposed on a substrate, the overhang structures comprising extensions disposed past the sidewalls of the overhang structures. The subpixel further comprises an anode disposed on the substrate and an inorganic layer disposed below each extension of the overhang structures. The subpixel is made by a process comprising depositing an organic light-emitting diode (OLED) material on a substrate. The OLED material is disposed on the anode. The inorganic layer below each extension of the overhang structures is disposed between the OLED materials. The process further comprises the step of depositing a cathode, and the cathode is disposed below each extension of the overhang structures.

[0007] In one or more embodiments, the method comprises the step of depositing an inorganic layer on a substrate and removing portions of the inorganic layer so that the inorganic layer is positioned under an extension of an overhang structure. The method further comprises the step of forming overhang structures. The overhang structures include an extension positioned over the sidewalls of the overhang structures. The method further comprises the step of depositing an organic light-emitting diode (OLED) material on a substrate. The OLED material is positioned on an anode. The inorganic layer under each extension of the overhang structures is positioned between the OLED materials. The method further comprises the step of depositing a cathode, and the cathode is positioned under each extension of the overhang structures. Brief explanation of the drawing

[0008] In a manner that enables a detailed understanding of the features described above of the present disclosure, a more specific description of the present disclosure, briefly summarized above, may be made with reference to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings are merely illustrative of exemplary embodiments and, therefore, should not be construed as limiting the scope thereof, and that other equally effective embodiments may be permitted. FIG. 1a is a schematic cross-sectional view of a subpixel circuit according to embodiments. FIG. 1b is a schematic cross-sectional view of a subpixel circuit according to one or more embodiments. FIGS. 2a to 2c are schematic cross-sectional views of an overhang structure of a subpixel circuit of FIG. 1a according to one or more embodiments. FIG. 3 is a schematic plan view of a subpixel circuit from FIG. 1a or FIG. 1b having a line-type architecture according to one or more embodiments. FIG. 4 is a flowchart of a method for forming a subpixel circuit according to one or more embodiments. FIGS. 5a to 5g are schematic cross-sectional views of a substrate during the method of FIG. 4 for forming a subpixel circuit according to one or more embodiments. FIG. 6 is a flowchart of a method for forming a subpixel according to one or more embodiments. FIGS. 7a to 7j are schematic cross-sectional views of a substrate during the method of FIG. 6 for forming a subpixel circuit according to one or more embodiments. For ease of understanding, the same reference numbers have been used to indicate the same elements common to the drawings where possible. The elements disclosed in one embodiment are considered to be useful for other embodiments without specific reference. Specific details for implementing the invention

[0009] The embodiments described herein generally relate to displays. More specifically, the embodiments described herein relate to a subpixel circuit and a method for forming the subpixel circuit that can be used in a display such as an organic light-emitting diode (OLED) display. In various embodiments, the subpixels utilize advanced overhang structures to improve the functionality of the display.

[0010] In one embodiment, a subpixel is provided. The subpixel comprises an anode, overhang structures, an inorganic layer, an organic light-emitting diode (OLED) material, and a cathode. The anode is defined by an adjacent first overhang structure and an adjacent second overhang structure. The overhang structures are disposed on the inorganic layer. The overhang structures include a second structure disposed on the first structure. The bottom surface of the second structure extends laterally past the top surface of the first structure. The OLED material is disposed on the upper surface of the anode and the inorganic layer. The cathode is disposed on the upper surface of the inorganic layer below the extensions of the second structures of the OLED material and the adjacent overhang structures. In one or more embodiments, a pixel isolation structure (PIS) is deposited below the adjacent overhang structures. In one or more embodiments, the PIS is deposited below the inorganic layer. In one or more embodiments, the PIS is deposited on the upper surface of the inorganic layer.

[0011] Each of the embodiments of the subpixel circuit described herein comprises a plurality of subpixels, and each subpixel is defined by adjacent overhang structures that are permanent to the subpixel circuit. Although the drawings depict two subpixels having each subpixel defined by adjacent overhang structures, the subpixel circuits of the embodiments described herein comprise a plurality of subpixels, such as two or more subpixels. Each subpixel has OLED materials configured to emit white, red, green, blue, or other color light when activated. For example, the OLED materials of the first subpixel emit red light when activated, the OLED materials of the second subpixel emit green light when activated, and the OLED materials of the third subpixel emit blue light when activated.

[0012] Overhangs are permanent to the subpixel circuit and include at least a second structure disposed on top of a first structure. Adjacent overhang structures defining each subpixel of the subpixel circuit of the display provide for the formation of the subpixel circuit using evaporative deposition and provide overhang structures to be retained in place after the subpixel circuit is formed. Evaporative deposition is utilized for the deposition of OLED materials (including a hole injection layer (HIL), a hole transport layer (HTL), an emission layer (EML), and an electron transport layer (ETL)) and a cathode. In some examples, an encapsulation layer may be disposed via evaporative deposition. In embodiments comprising one or more capping layers, the capping layers are disposed between the cathode and the encapsulation layer. Overhang structures and an evaporation angle set by an evaporation source define deposition angles, that is, the overhang structures provide a shielding effect during evaporative deposition having an evaporation angle set by an evaporation source. To deposit at a specific angle, the evaporation source is configured to emit deposition material at a specific angle with respect to the overhang structures. The encapsulation layer of each subpixel is positioned over the cathode, and the encapsulation layer extends down at least a portion of each of the adjacent overhang structures and along the sidewalls of each of the adjacent overhang structures.

[0013] FIG. 1a is a schematic cross-sectional view of a subpixel circuit (100) having a first protective layer configuration (101A) according to one or more embodiments. The cross-sectional view of FIG. 1a is taken along the cross-sectional line 1A-1A of FIG. 3 (e.g., pixel plane). FIG. 1b is a schematic cross-sectional view of a subpixel circuit (100) having a second protective layer configuration (101B) according to one or more embodiments. The cross-sectional view of FIG. 1b is taken along the cross-sectional line 1A-1A of FIG. 3 (e.g., pixel plane). The subpixel circuit (100) includes a substrate (102). In one or more embodiments, anodes (104) are pre-patterned on the substrate (102). For example, the substrate is pre-patterned with anodes (104) of indium tin oxide (ITO). The anodes (104) are configured to operate as anodes of each subpixel. In one embodiment, the anode (104) is a layer stack of a first transparent conductive oxide (TCO) layer, a second metal-containing layer disposed on the first TCO layer, and a third TCO layer disposed on the second metal-containing layer. The anodes (104) include, but are not limited to, chromium, titanium, gold, silver, copper, aluminum, ITO, combinations thereof, or other suitable conductive materials.

[0014] One or more PIS (126) are disposed on a substrate (102). The PIS (126) comprises one of an organic material, an organic material with an inorganic coating disposed thereon, or an inorganic material. The organic material of the PIS (126) includes polyimides, but is not limited thereto. The inorganic material of the PIS (126) includes silicon oxide (SiO2), silicon nitride (Si3N4), silicon oxynitride (Si2N2O), magnesium fluoride (MgF2), or a combination thereof, but is not limited thereto.

[0015] The subpixel circuit (100) has a plurality of subpixel lines (e.g., a first subpixel line (106A) and a second subpixel line (106B)). The subpixel lines are adjacent to each other along the pixel plane. FIG. 1a illustrates the first subpixel line (106A) and the second subpixel line (106B), but the subpixel circuit (100) of the embodiments described herein may include two or more subpixel lines, such as a third subpixel line and a fourth subpixel. Each subpixel line has OLED materials configured to emit white, red, green, blue, or other color light when activated. In one or more embodiments, the OLED materials within the pixel line are configured to emit the same color light when activated. In one or more embodiments, the OLED materials within the pixel line are configured to emit different colors of light when activated.

[0016] Each subpixel line includes overhang structures (110), and adjacent subpixel lines share the overhang structures (110) in the pixel plane. The overhang structures (110) are permanent for the subpixel circuit (100). The overhang structures (110) further define each subpixel line of the subpixel circuit (100). Each overhang structure (110) includes adjacent overhangs (109). The adjacent overhangs (109) are defined by an overhang extension (109A) of a second structure (110B) that extends laterally past the upper surface (105) of the first structure (110A). In one or more embodiments, the first structure (110A) is placed on the upper surface (181) of the inorganic layer (180).

[0017] The inorganic layer (180) is partially disposed on the PIS (126) and extends below the overhang extension (109A) over a portion of the anode (104) such that the extension width of the edge of the overhang extension (109A) of the sidewall (111) of the first structure (110A) is substantially the same as the extension width of the inorganic layer (180) disposed over the anode (104). The inorganic layer has a thickness of about 15 nm or less. The second structure (110B) is disposed on the first structure (110A). The second structure (110B) may be disposed on the upper surface (105) of the first structure (110A).

[0018] In one embodiment, the overhang structures (110) comprise a second structure (110B) of a conductive inorganic material and a first structure (110A) of a non-conductive inorganic material. The conductive materials of the second structure (110B) comprise copper (Cu), aluminum (Al), aluminum neodymium (AlNd), molybdenum (Mo), molybdenum tungsten (MoW), or combinations thereof. The non-conductive materials of the first structure (110A) comprise amorphous silicon (a-Si), titanium (Ti), silicon nitride (Si3N4), silicon oxide (SiO2), silicon oxynitride (Si2N2O), or combinations thereof. The overhang structures (110) can be maintained in place, that is, permanently.

[0019] Adjacent overhangs (109) are defined by an overhang extension (109A). At least the bottom surface (107) of the second structure (110B) is wider than the top surface (105) of the first structure (110A) to form the overhang extension (109A). The overhang extension (109A) of the second structure (110B) forms an overhang (109) and allows the second structure (110B) to shadow the first structure (110A). The shadowing of the overhang extension (109A) provides for the evaporative deposition of an inorganic layer (180), an OLED material (112), and a cathode (114). The inorganic layer (180) material may include a metal oxide-containing material, a silicon-containing material, or a combination thereof. The metal oxide-containing material includes, but is not limited to, aluminum oxide (Al2O3). Silicon-containing materials include, but are not limited to, silicon oxides, nitrides, or oxynitrides. Silicon oxides, nitrides, or oxynitrides include silicon oxide (SiO2) and silicon nitride (SiN2). xThe OLED material (112) may include, but is not limited to, silicon oxynitride (SiON), or combinations thereof. The OLED material (112) may include one or more of HIL, HTL, EML, and ETL. The OLED material (112) is partially disposed on the anode (104) in contact with it. The OLED material (112) disposed below the overhang extension (109A) is in contact with the upper surface (181) of the inorganic layer (180). The OLED material (112) may be disposed below adjacent overhangs (109) and may be in contact with the sidewall (111) of the first structure (110A). In one embodiment, the OLED material (112) is different from the material of the first structure (110A) and the second structure (110B). The cathode (114) is disposed on the OLED material (112) and extends below the adjacent overhangs (109). The cathode (114) may extend past the end point of the OLED material (112). The cathode (114) may come into contact with the upper surface (181) of the inorganic layer (180). The evaporation angle set by the overhang structures (110) and the evaporation source defines the deposition angles, that is, the overhang structures provide a shielding effect during evaporation deposition having an evaporation angle set by the evaporation source.

[0020] The cathode (114) comprises a conductive material, such as a metal. For example, the cathode (114) comprises, but is not limited to, silver, magnesium, chromium, titanium, aluminum, ITO, or a combination thereof. In one embodiment, the material of the cathode (114) is different from the material of the first structure (110A) and the second structure (110B). In one or more embodiments, the OLED material (112) and the cathode (114) do not come into contact with the sidewall (111) of the first structure (110A). In one or more embodiments, the OLED material (112) comes into contact with the sidewall (111) of the first structure (110A).

[0021] Each subpixel (106A, 106B) includes an encapsulation layer (116). The encapsulation layer (116) may be a local passivation layer or may correspond thereto. The encapsulation layer (116) of each subpixel is placed over the cathode (114) (and OLED material (112)), and the encapsulation layer (116) extends under at least a portion of each of the overhang extensions (109A) and along the sidewall (111) of each of the first structure (110A) and the second structure (110B). The encapsulation layer (116) is placed over the cathode (114) and extends between the cathode and the sidewall (111), and at least partially over the sidewall (111) and past the cathode (114). In some embodiments, the encapsulation layer (116) extends to contact the sidewall (111) of the first structure (110A). In the exemplary embodiments illustrated in FIGS. 1a and 1b, the encapsulation layer (116) extends to contact the second structure (110B) at the lower surface of the overhang extension (109A), the sidewall (113) of the second structure (110B), and the upper surface of the second structure (110B). In some embodiments, the encapsulation layer (116) extends to contact the second structure (110B) at the lower surface of the overhang extension (109A) and to be placed over the inorganic layer (180), the OLED material (112), and the cathode (114). In some embodiments, the encapsulation layer (116) ends at the sidewall (111) of the first structure (110A), that is, it is not disposed on the sidewall (113) of the second structure (110B), the upper surface of the second structure (110B), or the lower surface of the overhang extension (109A) of the overhang structures (110). The encapsulation layer (116) comprises a non-conductive inorganic material, e.g., a silicon-containing material. The silicon-containing material may include Si3N4-containing materials.

[0022] In embodiments comprising one or more capping layers, the capping layers are disposed between the cathode (114) and the encapsulation layer (116). For example, a first capping layer and a second capping layer are disposed between the cathode (114) and the encapsulation layer (116). Each of the embodiments described herein may include one or more capping layers disposed between the cathode (114) and the encapsulation layer (116). The first capping layer may include an organic material. The second capping layer may include an inorganic material, for example, lithium fluoride. The first capping layer and the second capping layer may be deposited by evaporative deposition. In another embodiment, the subpixel circuit (100) further includes at least a global passivation layer disposed over the overhang structure (110) and the encapsulation layer (116). In another embodiment, the subpixel includes an intermediate passivation layer disposed on each of the overhang structures (110) of the subpixels (106A, 106B) and between the encapsulation layer (116) and the global passivation layer.

[0023] FIG. 1b is a schematic cross-sectional view of a subpixel circuit (100) according to one or more embodiments. The subpixel circuit (100) having a second protective layer configuration (101B) includes an inorganic layer (180) disposed below a PIS (126). The PIS (126) is disposed on an upper surface (181) of the inorganic layer (180). The inorganic layer (180) extends between the sidewall (127) of the PIS and the sidewall (128) of the anode (104). The inorganic layer (180) extends below the overhang extension (109A) over a portion of the anode (104) such that the width of the edge of the overhang extension (109A) of the sidewall (111) of the first structure (110A) is substantially the same as the width of the inorganic layer (180) disposed above the anode (104). The inorganic layer has a thickness of about 15 nm or less.

[0024] FIGS. 2a through 2c are schematic cross-sectional views of an overhang structure (110) of a subpixel circuit (100) having a first protective layer configuration (101A) as illustrated in FIG. 1a, according to one or more embodiments. In FIG. 2a, an inorganic layer (180) is placed over the PIS (126). The first structure (110A) is placed over the upper surface (181) of the inorganic layer (180). The inorganic layer (180) extends between the first structure (110A) and the anode (104). The inorganic layer (180) extends below the overhang extension (109A) over a portion of the anode (104) such that the width of the edge of the overhang extension (109A) of the sidewall (111) of the first structure (110A) is substantially the same as the width of the inorganic layer (180) placed over the anode (104). The OLED material (112) is placed on the anode (104) and the inorganic layer (180) at two different angles ( θ a and θ b) is arranged. Angles θ a and θ b is approximately the same in opposite directions so that the deposition profile of the OLED material (112) is the same for the overhang structures (110) defining the subpixel. The OLED material (112) is deposited at an angle with respect to the overhang structures (110), and thus, the OLED material (112) deposited below the overhang extension (109A) has a smaller thickness than the OLED material (112) not below the overhang extension (109A). The thickness of the OLED material (112) below the overhang extension (109A) decreases as it approaches the sidewall (111). In one or more embodiments, the OLED material (112) is deposited at an angle so that the OLED material (112) does not come into contact with the sidewall (111). The OLED material (112) is placed at least partially on the inorganic layer (180) below the overhang extension (109A). In one or more embodiments, the OLED material (112) is deposited at an angle so as to be in contact with the sidewall (111).

[0025] In FIG. 2b, the cathode (114) has two different angles ( θ a and θ b) is placed on the OLED material (112) and inorganic layer (180). Angles θ a and θ b is approximately the same in opposite directions so that the deposition profile of the cathode (114) is the same for the overhang structures (110) defining the subpixel. The cathode (114) is deposited at an angle with respect to the overhang structures (110), and thus, the cathode (114) deposited below the overhang extension (109A) has a smaller thickness than the cathode (114) not below the overhang extension (109A). The thickness of the cathode (114) below the overhang extension (109A) decreases as it approaches the sidewall (111). In one or more embodiments, the cathode (114) is deposited at an angle so that the cathode (114) does not come into contact with the sidewall (111). In one or more embodiments, the cathode (114) extends past the OLED material (112) and comes into direct contact with the inorganic layer (180). The inorganic layer (180) prevents electrical leakage between the anode (104) and the cathode (114) deposited below the overhang extension (109A), and at this location, the OLED material (112) may be too thin to prevent electrical leakage.

[0026] In FIG. 2c, the encapsulation layer (116) is deposited on the cathode (114), the OLED material (112), and the inorganic layer (180). In one or more embodiments, the encapsulation layer (116) extends along the sidewall (111), across the bottom surface of the overhang extension (109A), and over the second structure (110B). In one or more embodiments, the encapsulation layer (116) extends across the gap between the cathode (114) and the sidewall (111), and the encapsulation layer (116) is in direct contact with the upper surface (181) of the inorganic layer (180).

[0027] FIG. 3 is a schematic plan view of a subpixel circuit (100) having either a first protection layer configuration (101A) or a second protection layer configuration (101B), having a line-type architecture (300) according to embodiments. The line-type architecture (300) includes a plurality of pixel openings (124). Each pixel opening (124) is abutted by overhang structures (110) and separation structures (125) that define each of the subpixel lines and subpixels of the line-type architecture (300).

[0028] Each subpixel line includes separation structures (125), and adjacent subpixels share separation structures (125). Separation structures (125) are permanent in the subpixel circuit (100). Separation structures (125) further define each subpixel of the subpixel line of the subpixel circuit (100).

[0029] FIG. 4 is a flowchart of a method (400) for forming a subpixel circuit (100) having a first protective layer configuration (101A) according to one or more embodiments. FIG. 5a to 5g are schematic cross-sectional views of a substrate (102) during the method (400) for forming a subpixel circuit (100) having a first protective layer configuration (101A) according to one or more embodiments.

[0030] In operation 402, as illustrated in FIG. 5a, anodes (104) are formed on a substrate. This can be done by depositing a layer of anodes on the substrate (102) and then depositing a photoresist pattern on the anode layer. The anode layer not protected by the photoresist pattern is then etched away to form the desired anodes (104).

[0031] In operation 404, as illustrated in FIGS. 5b through 5d, a pixel isolation (PI) layer (526) is deposited on the anodes (104) and the substrate (102). The PI layer (526) as illustrated in FIG. 5b is deposited on the anodes (104) and the substrate (102). Then, the PI layer (526) is etched away to form a first PIS (126A), a second PIS (126B), and a third PIS (126C) between the anodes (104) as illustrated in FIG. 5c. Then, the PIS (126A, 126B, 126C) are flattened so that the top surfaces of each PIS (126A, 126B, 126C) are aligned with each other and are below the top surface of the anodes (104) as illustrated in FIG. 5d.

[0032] In operation 406, as illustrated in FIG. 5e, an inorganic layer (180) is deposited on the anodes (104) and PIS (126A, 126B, 126C). In one or more embodiments, the inorganic layer (180) is deposited using evaporative deposition. In one or more embodiments, the inorganic layer (180) is made of a dielectric material such as aluminum oxide (Al2O3).

[0033] In operation 408 as illustrated in FIG. 5f, overhang structures (110) are formed on each PIS (126A, 126B, 126C) on top of the inorganic layer (180). The overhang structures (110) can be formed by depositing a first overhang layer and a second overhang layer, and by etching away desired areas using photoresist to form the overhang structures.

[0034] In operation 410 as illustrated in FIG. 5g, exposed areas of the inorganic layer (180) not protected by the overhang extensions (109A) are etched away so that the portions of the inorganic layer (180) located below the overhang extensions (109A) of the overhang structures (110) remain. The portion of the inorganic layer (180) extending over the anode (104) has a width approximately equal to the width of the overhang extension (109A).

[0035] FIG. 6 is a flowchart of a method (600) for forming a subpixel circuit (100) having a second protective layer configuration (101B) as shown in FIG. 1b, according to one or more embodiments. FIG. 7a through 7j are schematic cross-sectional views of a substrate (102) during the method (600) for forming a subpixel circuit (100) having a second protective layer configuration (101B), according to one or more embodiments.

[0036] In operation 602 as illustrated in FIG. 7a, anodes (104) are formed on a substrate (102). This can be done by depositing a layer of anodes on the substrate (102) and then depositing a photoresist pattern on the anode layer. The anode layer not protected by the photoresist pattern is then etched away to form the desired anodes (104).

[0037] In operation 604 as illustrated in FIG. 7b, an inorganic layer (180) is deposited on the substrate (102) and the anodes (104). In one or more embodiments, the inorganic layer (180) is deposited using evaporative deposition. In one or more embodiments, the inorganic layer (180) is made of a dielectric material such as aluminum oxide (Al2O3).

[0038] In operation 606 as illustrated in FIG. 7c, a photoresist pattern (710) is deposited on an inorganic layer (180). A positive photoresist or a negative photoresist may be used in this operation.

[0039] In operation 608 as illustrated in FIGS. 7d ​​through 7e, the inorganic layer (180) not protected by the photoresist pattern (710) is etched away. The photoresist pattern (710) extends over the anode (104) such that a portion of the inorganic layer (180) extends over the top of the anode (104). The width of the inorganic layer (180) placed on the anode (104) is approximately equal to the width of the overhang extension (109A) of the overhang structure (110) to be placed over the inorganic layer (180). Then, the photoresist pattern (710) is removed as illustrated in FIG. 7e.

[0040] In operation 610, as illustrated in FIGS. 7f through 7h, a pixel isolation (PI) layer (526) is deposited on the anodes (104) and the inorganic layer (180). The PI layer (526) as illustrated in FIG. 7f is deposited on the anodes (104) and the substrate (102). Then, the PI layer (526) is etched away to form a first PIS (126A), a second PIS (126B), and a third PIS (126C) between the anodes (104) on top of the inorganic layer (180) as illustrated in FIG. 7g. Next, the PIS (126A, 126B, 126C) are flattened so that the top surfaces of each PIS (126A, 126B, 126C) are aligned with one another and are below the top surface of the anodes (104) as shown in FIG. 7h. In one or more embodiments, operation 610 is performed prior to operation 602. In one or more embodiments, operation 602 is performed prior to operation 610.

[0041] In operation 612, as illustrated in FIGS. 7i through 7j, overhang structures (110) are formed on each PIS (126A, 126B, 126C) on the top of the inorganic layer (180). The overhang structures (110) may be formed by depositing a first overhang layer and a second overhang layer, and by etching away desired regions using a photoresist to form the overhang structures. In one or more embodiments, operation 612 is performed prior to operation 602. In one or more embodiments, operation 602 is performed prior to operation 612.

[0042] In summary, a device is disclosed. The device includes a plurality of subpixels. Each subpixel includes an anode, an inorganic layer, overhang structures, separation structures, an organic light-emitting diode (OLED) material, and a cathode. The anode is defined by adjacent overhang structures. The overhang structures are disposed on the inorganic layer. The overhang structures include a second structure disposed on the first structure. The bottom surface of the second structure extends laterally past the top surface of the first structure. The OLED material is disposed on the anode and the inorganic layer. The cathode is disposed on the OLED material and the inorganic layer.

[0043] The advantages of the present disclosure include reduced electrical leakage between the anode and cathode and improved device performance.

[0044] One or more embodiments disclosed herein are considered to be combinable. For example, one or more embodiments, features, components, operations, and / or characteristics of various implementations of a subpixel circuit (100), a first protection layer configuration (101A), a second protection layer configuration (101B), an inorganic layer (180), an anode (104), a PIS (126), overhang structures (110), an OLED material (112), a cathode (114), an encapsulation layer (116), a method (400), and / or method (600) may be combined. Furthermore, one or more embodiments disclosed herein are considered to include some or all of the aforementioned advantages.

[0045] Although the foregoing relates to embodiments of the present disclosure, other and additional embodiments of the present disclosure may be devised without departing from the basic scope thereof, the scope thereof being determined by the following claims.

Claims

Claim 1 A subpixel comprising: a substrate; overhang structures—the overhang structures include extensions disposed through the sidewalls of the overhang structures—; an anode disposed on the substrate; an inorganic layer disposed below each extension of the overhang structures; an organic light-emitting diode (OLED) material disposed on the anode—the OLED material is disposed between the inorganic layers below each extension of the overhang structures—; and a cathode disposed on the OLED material. Claim 2 A subpixel according to claim 1, further comprising isolation structures disposed on the substrate, wherein adjacent isolation structures have an anode between them. Claim 3 In claim 1, the extension width from the edge of the extension portion to the side wall is substantially the same as the width of the inorganic layer from the edge of the inorganic layer to the side wall of each overhang structure, subpixel. Claim 4 In paragraph 2, the weapon layer is a subpixel disposed on the isolation structures. Claim 5 In paragraph 2, the weapon layer is a subpixel disposed below the isolation structures. Claim 6 In claim 1, the inorganic layer comprises a dielectric material, a subpixel. Claim 7 In claim 1, the inorganic layer comprises a metal oxide-containing material, a silicon-containing material, or a combination thereof, in a subpixel. Claim 8 In claim 1, the inorganic layer has a thickness of 15 nm or less, a subpixel. Claim 9 A subpixel according to claim 1, further comprising an encapsulation layer disposed on the cathode and, passing through the end of the cathode—the encapsulation layer extending along the sidewall of the overhang structures below at least a portion of the extensions of the overhang structures and in contact with the bottom surface of the extensions of the overhang structures. Claim 10 In claim 1, the OLED material is a subpixel disposed on at least a portion of the inorganic layer. Claim 11 A subpixel comprising, wherein the subpixel comprises overhang structures disposed on a substrate including extensions disposed past the sidewalls of the overhang structures, an anode disposed on the substrate, and an inorganic layer disposed below each extension of the overhang structures, and the subpixel is formed by a process comprising the step of depositing an organic light-emitting diode (OLED) material on the substrate—the OLED material being disposed on the anode and the inorganic layer below each extension of the overhang structures being disposed between the OLED materials—; and the step of depositing a cathode—the cathode being disposed below each extension of the overhang structures. Claim 12 In claim 11, the inorganic layer is a subpixel deposited using evaporative deposition. Claim 13 In claim 11, the OLED material is deposited at an angle with respect to the substrate, forming a subpixel. Claim 14 In claim 11, the subpixel further comprises isolation structures disposed on the substrate, wherein adjacent isolation structures have an anode between them. Claim 15 A method comprising: a step of depositing an inorganic layer on a substrate; a step of removing portions of the inorganic layer such that the inorganic layer is disposed below extensions of overhang structures; a step of forming the overhang structures—the overhang structures include extensions disposed past the sidewalls of the overhang structures—; a step of depositing an organic light-emitting diode (OLED) material on the substrate—the OLED material is disposed on an anode, and the inorganic layer below each extension of the overhang structures is disposed between the OLED materials—; and a step of depositing a cathode—the cathode is disposed below each extension of the overhang structures. Claim 16 A method according to claim 15, further comprising the steps of: depositing a pixel isolation layer on the substrate; and removing portions of the pixel isolation layer so that pixel isolation structures are disposed below a first portion of the overhang structure. Claim 17 In claim 16, the method wherein the inorganic layer is deposited prior to the pixel isolation layer. Claim 18 In claim 16, the pixel isolation layer is deposited prior to the inorganic layer, in a method. Claim 19 In paragraph 16, a method in which portions of the above-mentioned inorganic layer are removed before forming the above-mentioned overhang structures. Claim 20 In paragraph 16, a method in which portions of the above-mentioned weapon layer are removed after forming the above-mentioned overhang structures.

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