Light absorbing layers for use in OLED device

Abstract

Embodiments described herein generally relate to a display. More specifically, embodiments described herein relate to sub-pixel circuits and methods of forming sub¬ pixel circuits that may be utilized in a display such as an organic light-emitting diode (OLED) display. In one or more embodiments, a sub-pixel circuit includes a substrate. Overhang structures are disposed over the substrate. The overhang structures define sub-pixels of the sub-pixel circuit. The overhang structures include an upper structure disposed over a lower structure. The sub-pixel circuit further includes a plurality of sub¬ pixels. Each sub-pixel includes an anode. An organic light-emitting (OLE) material is disposed over and in contact with the anode. A cathode is disposed over the OLE material. An encapsulation layer is disposed over the cathode. A light absorbing material is disposed over the upper structure of the overhang structures.

Description

PATENTAttorney Docket No.: 44025989WO01LIGHT ABSORBING LAYERS FOR USE IN OLED DEVICE BACKGROUNDField

[0001] Embodiments described herein generally relate to a display. More specifically, embodiments described herein relate to sub-pixel circuits and methods of forming sub-pixel circuits that may be utilized in a display such as an organic lightemitting diode (OLED) display.Description of the Related Art

[0002] Input devices including display devices may be used in a variety of electronic systems. An organic light-emitting diode (OLED) is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of an organic compound that emits light in response to an electric current. OLED devices are classified as bottom emission devices if light emitted passes through the transparent or semitransparent bottom electrode and substrate on which the panel was manufactured. Top emission devices are classified based on whether or not the light emitted from the OLED device exits through the lid that is added following the fabrication of the device. OLEDs are used to create display devices in many electronics today. Today’s electronics manufacturers are pushing these display devices to shrink in size while providing higher resolution, i.e. , pixel-per-inch, than just a few years ago.

[0003] OLED pixel patterning is currently based on a process that restricts panel size, pixel resolution, and substrate size. Rather than utilizing a fine metal mask, photo lithography should be used to pattern pixels. Currently, OLED pixel patterning requires lifting off organic material after the patterning process. When lifted off, the organic material leaves behind a particle issue that disrupts OLED performance.

[0004] Accordingly, what is needed in the art are sub-pixel circuits and methods of forming sub-pixel circuits to increase pixel-per-inch and provide improved OLED performance.PATENTAttorney Docket No.: 44025989WO01SUMMARY

[0005] Embodiments described herein generally relate to a display. More specifically, embodiments described herein relate to sub-pixel circuits and methods of forming sub-pixel circuits that may be utilized in a display such as an organic lightemitting diode (OLED) display.

[0006] In one or more embodiments, a sub-pixel circuit includes a substrate. Overhang structures are disposed over the substrate. The overhang structures define sub-pixels of the sub-pixel circuit. The overhang structures include an upper structure disposed over a lower structure. The sub-pixel circuit further includes a plurality of subpixels. Each sub-pixel includes an anode. An organic light-emitting (OLE) material is disposed over and in contact with the anode. A cathode is disposed over the OLE material. An encapsulation layer is disposed over the cathode. A light absorbing material is disposed over the upper structure of the overhang structures.

[0007] In one or more embodiments, a sub-pixel circuit includes a substrate. Overhang structures are disposed over the substrate. The overhang structures define sub-pixels of the sub-pixel circuit. The overhang structures include an upper structure disposed over a lower structure. The sub-pixel circuit further includes a plurality of subpixels. Each sub-pixel includes an anode. An organic light-emitting (OLE) material is disposed over and in contact with the anode. A cathode is disposed over the OLE material. A first thin film encapsulation (TFE) layer is disposed over the cathode. A light absorbing material is disposed over the upper structure of the overhang structures. A global encapsulation layer is deposited over the first TFE layer and the light absorbing material. A second TFE layer is deposited over the global encapsulation layer.

[0008] In one or more embodiments, a sub-pixel circuit includes a substrate. Overhang structures are disposed over the substrate. The overhang structures define sub-pixels of the sub-pixel circuit. The overhang structures include an upper structure disposed over a lower structure. The sub-pixel circuit further includes a plurality of subpixels. Each sub-pixel includes an anode. An organic light-emitting (OLE) material is disposed over and in contact with the anode. A cathode is disposed over the OLE material. A first thin film encapsulation (TFE) layer is disposed over the cathode. APATENTAttorney Docket No.: 44025989WO01light absorbing material is disposed over the upper structure of the overhang structures. A global encapsulation layer is deposited over the first TFE layer and the light absorbing material. A second TFE layer is deposited over the global encapsulation layer. Color filters are patterned over the second TFE layer to align over the OLE material of each sub-pixel. An outer encapsulation layer is disposed over the color filters.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only exemplary embodiments and are therefore not to be considered limiting of its scope, and may admit to other equally effective embodiments.

[0010] Figure 1 is a schematic, cross-sectional view of a sub-pixel circuit, according to one or more embodiments.

[0011] Figure 2 is a schematic, cross-sectional view of a sub-pixel circuit, according to one or more embodiments.

[0012] Figure 3 is a schematic, cross-sectional view of a sub-pixel circuit, according to one or more embodiments.

[0013] Figure 4 is a schematic, cross-sectional view of a sub-pixel circuit, according to one or more embodiments.

[0014] Figure 5 is a schematic, cross-sectional view of a sub-pixel circuit, according to one or more embodiments.

[0015] Figure 6 is a schematic, cross-sectional view of a sub-pixel circuit, according to one or more embodiments.

[0016] Figure 7 is a schematic, cross-sectional view of a sub-pixel circuit, according to one or more embodiments.PATENTAttorney Docket No.: 44025989WO01

[0017] Figure 8 is a schematic, cross-sectional view of a sub-pixel circuit, according to one or more embodiments.

[0018] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.DETAILED DESCRIPTION

[0019] Embodiments described herein generally relate to a display. More specifically, embodiments described herein relate to sub-pixel circuits and methods of forming sub-pixel circuits that may be utilized in a display such as an organic lightemitting diode (OLED) display. In one embodiment, which can be combined with other embodiments described herein, the display is a bottom emission (BE) or a top emission (TE) OLED display.

[0020] A first exemplary embodiment of the embodiments described herein includes a sub-pixel circuit having a dot-type architecture. A second exemplary embodiment of the embodiments described herein includes a sub-pixel circuit having a line-type architecture. Each of the embodiments (including the exemplary embodiments) described herein of the sub-pixel circuit include a plurality of sub-pixels with each of the sub-pixels defined by adjacent inorganic overhang structures that are permanent to the sub-pixel circuit. Each sub-pixel has an organic light emitting (OLE) material configured to emit a white, red, green, blue or other color light when energized. E.g., the OLE material of a first sub-pixel emits a red light when energized, the OLE material of a second sub-pixel emits a green light when energized, and the OLED material of a third sub-pixel emits a blue light when energized.

[0021] The inorganic overhang structures are permanent to the sub-pixel circuit and include at least an upper structure disposed on a lower structure. A first configuration of the inorganic overhang structures includes the upper structure of a non-conductive inorganic material and the lower structure of a conductive inorganic material. A second configuration of the inorganic overhang structures includes the upper structure of a conductive inorganic material and the lower structure of aPATENTAttorney Docket No.: 44025989WO01conductive inorganic material. A third configuration of the inorganic overhang structures includes the upper structure of a non-conductive inorganic material, the lower structure of a non-conductive inorganic material, and an assistant cathode disposed under the lower structure. A fourth configuration of the inorganic overhang structures includes the upper structure of a conductive inorganic material, the lower structure of a non-conductive inorganic material, and an assistant cathode disposed under the lower structure. Any of the exemplary embodiments include inorganic overhang structures of at least one of the first, second, third, or fourth configurations.

[0022] The adjacent inorganic overhang structures defining each sub-pixel of the sub-pixel circuit of the display provide for formation of the sub-pixel circuit using evaporation deposition and provide for the inorganic overhang structures to remain in place after the sub-pixel circuit is formed. Evaporation deposition may be utilized for deposition of an OLE material (including a hole injection layer (HIL), a hole transport layer (HTL), an emissive layer (EML), and an electron transport layer (ETL)) and cathode. One or more of an encapsulation layer, and a global passivation layer may be disposed via evaporation deposition. In embodiments including one or more capping layers, the capping layers are disposed between the cathode and the encapsulation layer. The inorganic overhang structures define deposition angles, i.e. , provide for a shadowing effect during evaporation deposition, for each of the OLE material and the cathode such the OLE material does not contact the lower structure (and assistant cathode according to embodiments with the third and fourth configurations) and the cathode contacts the lower structure according to the first and second configurations or at least the assistant cathode of the third and fourth configurations. In one or more embodiments, both the OLE material and the cathode contact the lower structure. The encapsulation layer of a respective sub-pixel is disposed over the cathode with the encapsulation layer extending under at least a portion of each of the adjacent inorganic overhang structures and along a sidewall of each of the adjacent inorganic overhang structures.

[0023] Figure 1 is a schematic, cross-sectional view of a sub-pixel circuit 100, according to one or more embodiments. The sub-pixel circuit 100 includes a substrate 102. Metal layers 104 may be patterned on or over the substrate 102 and are definedPATENTAttorney Docket No.: 44025989WO01by adjacent pixel-defining layer (PDL) structures 126 disposed on or over the substrate 102. In one embodiment, which can be combined other embodiments described herein, the metal layers 104 are pre-patterned on or over the substrate 102. E.g., the substrate 102 is a pre-patterned indium tin oxide (ITO) glass substrate. The metal layers 104 are configured to operate anodes of respective sub-pixels. The metal layers 104 include, but are not limited to, chromium, titanium, gold, silver, copper, aluminum, ITO, a combination thereof, or other suitably conductive materials. In one or more embodiments, the metal layers 104 are each a layer stack of a first transparent conductive oxide (TOO) layer, a second metal-containing layer disposed on the first TOO layer, and a third TOO layer disposed on the second metal-containing layer.

[0024] The PDL structures 126 are disposed on or over the substrate 102. The PDL structures 126 include one of an organic material, an organic material with an inorganic coating disposed thereover, or an inorganic material. The organic material of the PDL structures 126 includes, but is not limited to, polyimides. The inorganic material of the PDL structures 126 includes, but is not limited to, silicon oxide (SiC>2), silicon nitride (SisN4), silicon oxynitride (Si2N2O), magnesium fluoride (MgF2), or combinations thereof. Adjacent PDL structures 126 define a respective sub-pixel and expose the anode (i.e., metal layer 104) of the respective sub-pixel of the sub-pixel circuit 100.

[0025] The sub-pixel circuit 100 has a plurality of sub-pixels 108 including at least a first sub-pixel 108A, a second sub-pixel 108B, and a third sub-pixel 108C. While the Figures depict the first sub-pixel 108A, the second sub-pixel 108B, and the third subpixel 108C, the sub-pixel circuit 100 of the embodiments described herein may include any number of sub-pixels, such as two sub-pixels, three sub-pixels, or four sub-pixels. Each sub-pixel 108 has an organic light emitting (OLE) material 112 configured to emit a white, yellow, red, green, blue or other color light when energized. E.g., the OLE material 112 of the first sub-pixel 108A emits a red light when energized, the OLE material of the second sub-pixel 108B emits a green light when energized, and the OLE material of the third sub-pixel 108C emits a blue light when energized. In one or more embodiments, one or more of the sub-pixels includes an OLE material 112 configured to emit a white or a yellow light.PATENTAttorney Docket No.: 44025989WO01

[0026] Inorganic overhang structures 110 are disposed on or over an upper surface of each of the PDL structures 126. The overhang structures 110 are permanent to the sub-pixel circuit. The overhang structures 110 further define each sub-pixel 108 of the sub-pixel circuit 100. The overhang structures 110 include at least an upper structure 110B disposed on or over a lower structure 110A. A first configuration of the overhang structures 110 includes the upper structure 110B of a non-conductive inorganic material and the lower structure 110A of a conductive inorganic material. A second configuration of the overhang structures 110 includes the upper structure 110B of a conductive inorganic material and the lower structure 110A of a conductive inorganic material. A third configuration of the overhang structures 110 includes the upper structure 110B of a non-conductive inorganic material, the lower structure 110A of a non-conductive inorganic material, and an assistant cathode disposed under the lower structure 110A. A fourth configuration of the overhang structures 110 includes the upper structure 110B of a conductive inorganic material, the lower structure 110A of a non-conductive inorganic material, and an assistant cathode disposed under the lower structure 110A. It is contemplated that in one or more embodiments, the first configuration and the second configuration further include an assistant cathode disposed under the lower structure 110A. The first, second, third, and fourth exemplary embodiments of the sub-pixel circuit 100 include overhang structures 110 of at least one of the first, second, third, or fourth configurations. The overhang structures 110 are able to remain in place, i.e. , are permanent. Thus, organic material from lifted off overhang structures that disrupt OLED performance would not be left behind. Eliminating the need for a lift-off procedure also increases throughput.

[0027] The non-conductive inorganic material includes, but it not limited to, an inorganic silicon-containing material. E.g., the silicon-containing material includes oxides or nitrides of silicon, or combinations thereof. The conductive inorganic material includes, but it not limited to, a metal-containing material. E.g., the metalcontaining material includes copper, titanium, aluminum, molybdenum, silver, indium tin oxide, indium zinc oxide, chromium or combinations thereof.

[0028] At least a bottom surface 107 of the upper structure 110B is wider than a top surface 105 of the lower structure 110A to form an overhang 109. The bottomPATENTAttorney Docket No.: 44025989WO01surface 107 larger than the top surface 105 forming the overhang 109 allows for the upper structure 11 OB to shadow the lower structure 110A. The shadowing of the overhang 109 provides for evaporation deposition each of the OLE material 112 and a cathode 114.

[0029] The OLE material 112 may include one or more of a HIL, a HTL, an EML, and an ETL. The OLE material 112 is disposed on the metal layer 104. In some embodiments, which can be combined with other embodiments described herein, the OLE material 112 is disposed on the metal layer 104 and over a portion of the PDL structures 126. The cathode 114 is disposed on or over the OLE material 112 of the PDL structures 126 in each sub-pixel 108. The cathode 114 includes a conductive material, such as a metal. E.g., the cathode 114 includes but is not limited to, silver, chromium, titanium, aluminum, ITO, or a combination thereof. The assistant cathode includes, but it not limited to, a metal-containing material. For example, the metalcontaining material includes copper, titanium, aluminum, molybdenum, silver, indium tin oxide, indium zinc oxide, chromium or combinations thereof.

[0030] Each sub-pixel 108 includes a first thin film encapsulation (TFE) layer 116. The first TFE layer 116 may be or may correspond to a local passivation layer. The first TFE layer 116 of a respective sub-pixel is disposed over the cathode 114 (and OLE material 112) with the first TFE layer 116 extending under at least a portion of each of the overhang structures 110 and along a sidewall of each of the overhang structures 110. The first TFE layer 116 is disposed on or over the cathode 114 and over at least the sidewall 111 of the lower structure 110A. In some embodiments, which can be combined with other embodiments described herein, the first TFE layer 116 is disposed on or over the upper sidewall 113 of the upper structure 110B. The first TFE layer 116 includes the non-conductive inorganic material, such as the silicon-containing material. The silicon-containing material may include SisN4 containing materials. In one or more embodiments, the first TFE layer 116 is deposited using a chemical vapor deposition (CVD) process. An opening 150 is formed between the first TFE layer 116 over a portion of the upper structure 110B of the overhang structures 110. In one or more embodiments, after an etching process is performed, a gap isPATENTAttorney Docket No.: 44025989WO01formed between an upper surface of the upper structure 110B of the overhang material and the first TFE layer 116.

[0031] In embodiments including one or more capping layers, the capping layers are disposed between the cathode 114 and the first TFE layer 116. While Figure 1 depicts the sub-pixel circuit 100 without any capping layers, each of the embodiments described herein may include one or more capping layers disposed between the cathode 114 first TFE layer 116.

[0032] A blackening material 122 is patterned to align over the overhang structures 110. In one or more embodiments, the blackening material 122 is a light absorbing material. In one or more embodiments, the blackening material 122 is deposited using an inkjet printing (IJP) process. In one or more embodiments the blackening material includes a black ink material. The blackening material 122 is disposed within the gap formed between the upper surface of the upper structure 110B of the overhang structures 110 and the first TFE layer 116. The blackening material 122 extends through the opening 150 formed between the first TFE layer 116 on or over a portion of the upper structure 110B of the overhang structures 110. The blackening material 122 extends onto the sidewalls 151 of the opening 150 and over an uppermost surface 152 of the first TFE layer 116 deposited over the overhang structures 110. The blackening material 122 absorbs ambient light traveling through the sub-pixel circuit 100. The blackening material 122 helps define the sub-pixels 108 and improves the overall image quality of the sub-pixel circuit 100. In one or more embodiments, the blackening material 122 is deposited using a slit coating process. In one or more embodiments, the blackening material 122 is deposited using a lithography patterning process.

[0033] A global encapsulation layer 118 is deposited over the blackening material 122 and the first TFE layer 116. The global encapsulation layer 118 layers covers the overhang structures 110, the blackening material 122, and the first TFE layer 116. The global encapsulation layer fills the sub-pixels 108. In one or more embodiments, the global encapsulation layer 118 layer is an inkjet layer. In one or more embodiments, the global encapsulation layer is deposited using an inkjet printing process. In one or more embodiments, the global encapsulation layer 118 is planarized.PATENTAttorney Docket No.: 44025989WO01

[0034] A second TFE layer 120 is deposited over the global encapsulation layer 118. In one or more embodiments, the second TFE layer 120 and the first TFE layer 116 are formed of the same material. In one or more embodiments, the upper surface of the second TFE layer 120 is planarized. Color filters 124 are patterned to align over the OLE material 112 of each sub-pixel 108. Each color filter 124 aligns over a corresponding OLE material 112 (e.g., a red color filter will align over a red OLE material 112, a green color filter will align over a green OLE material 112, a blue color filter will align over a blue OLE material 112). In one or more embodiments, one or more of the sub-pixels 108 include an OLE material configured to emit a white or yellow light. One or more color filters 124 are aligned with each sub-pixel 108 emitting a white or yellow light. As the light emitted y the OLE material 112 within each sub-pixel 108 travels through the color filter 124, the color filter 124 changes the color of the light emitted through the color filter 124. The color filters 124 are operable to provide an increased brightness of the colored light emitted from the final display device. In one or more embodiments, adjacent color filters 124 may overlap over the overhang structures 110. An outer encapsulation layer 130 is deposited over the color filters 124 in order to cover and protect the color filters 124 and the sub-pixel circuit 100.

[0035] Figure 2 is a schematic, cross-sectional view of a sub-pixel circuit 200, according to one or more embodiments. The sub-pixel circuit 200 is similar to the subpixel circuit 100 shown in Figure 1, and includes one or more of the aspects, features, components, properties, and / or operations thereof.

[0036] In one or more embodiments, the sub-pixel circuit 200 includes a black layer 222 disposed over the portion of the upper surface of the upper structure 110B of the overhang structure 110 exposed by the opening 150 of the first TFE layer 116. The black layer 222 extends onto the sidewalls 151 of first TFE layer 116 defining the opening 150 and extend on to at least a portion of the uppermost surface 152 of the first TFE layer 116. In one or more embodiments, the black layer 222 is deposited suing a chemical vapor deposition (CVD) process or a physical vapor deposition (PVD) process. The black layer 222 includes carbon, chromium carbonitride (CrCN), chromium nitride (CrN), ora combination thereof. The black layer 222 absorbs ambientPATENTAttorney Docket No.: 44025989WO01light traveling through the sub-pixel circuit 200. The black layer 222 helps define the sub-pixels 108 and improves the overall image quality of the sub-pixel circuit 200.

[0037] A global encapsulation layer 118 is deposited over the black layer 222 and the first TFE layer 116. In one or more embodiments, the black layer 222 is a light absorbing material. The global encapsulation layer 118 layers covers the overhang structures 110, the black layer 222, and the first TFE layer 116. The global encapsulation layer fills the sub-pixels 108. In one or more embodiments, the global encapsulation layer is deposited within the opening 150 and fills the gap between the upper surface of the upper structure 110B of the overhang structures 110 and the first TFE layer 116. In one or more embodiments, the global encapsulation layer 118 layer is an inkjet layer. In one or more embodiments, the global encapsulation layer 118 is planarized.

[0038] A second TFE layer 120 is deposited over the global encapsulation layer 118. In one or more embodiments, the second TFE layer 120 and the first TFE layer 116 are formed of the same material. In one or more embodiments, the upper surface of the second TFE layer 120 is planarized. Color filters 124 are patterned to align over the OLE material 112 of each sub-pixel 108. Each color filter 124 aligns over a corresponding OLE material 112 (e.g., a red color filter will align over a red OLE material 112, a green color filter will align over OLE material 112, a blue color filter will align over a blue OLE material 112). In one or more embodiments, one or more of the sub-pixels 108 include an OLE material configured to emit a white or yellow light. One or more color filters 124 are aligned with each sub-pixel 108 emitting a white or yellow light. As the light emitted y the OLE material 112 within each sub-pixel 108 travels through the color filter 124, the color filter 124 changes the color of the light emitted through the color filter 124. The color filters 124 are operable to provide an increased brightness of the colored light emitted from the final display device. In one or more embodiments, adjacent color filters 124 may overlap with one another over the overhang structures 110. An outer encapsulation layer 130 is deposited over the color filters 124 in order to cover and protect the color filters 124 and the sub-pixel circuit 200.PATENTAttorney Docket No.: 44025989WO01

[0039] Figure 3 is a schematic, cross-sectional view of a sub-pixel circuit 300, according to one or more embodiments. The sub-pixel circuit 300 is similar to the subpixel circuit 100 shown in Figure 1, and includes one or more of the aspects, features, components, properties, and / or operations thereof.

[0040] In one or more embodiments, the sub-pixel circuit 300 includes a blackening material 122 is patterned to align over the overhang structures 110. In one or more embodiments, the blackening material 122 is deposited using an inkjet printing (IJP) process. In one or more embodiments the blackening material includes a black ink material. The blackening material 122 is disposed within the gap formed between the upper surface of the upper structure 110B of the overhang structures 110 and the first TFE layer 116. The blackening material 122 extends through the opening 150 formed between the first TFE layer 116 over a portion of the upper structure 110B of the overhang structures 110. The blackening material 122 extends onto the sidewalls 151 of the opening 150 and over an uppermost surface 152 of the first TFE layer 116 deposited over the overhang structures 110. The blackening material 122 absorbs ambient light traveling through the sub-pixel circuit 300. The blackening material 122 helps define the sub-pixels 108 and improves the overall image quality of the sub-pixel circuit 300.

[0041] A global encapsulation layer 118 is deposited over the blackening material 122 and the first TFE layer 116. The global encapsulation layer 118 layers covers the overhang structures 110, the blackening material 122, and the first TFE layer 116. The global encapsulation layer fills the sub-pixels 108. In one or more embodiments, the global encapsulation layer 118 layer is an inkjet layer. In one or more embodiments, the global encapsulation layer 118 is planarized.

[0042] A second TFE layer 120 is deposited over the global encapsulation layer 118. In one or more embodiments, the second TFE layer 120 and the first TFE layer 116 are formed of the same material. In one or more embodiments, the upper surface of the second TFE layer 120 is planarized. A polarizer 324 is deposited over the second TFE layer 120. The polarizer 324 filters the light emitted by the OLE material 112 of each sub-pixel 108. The polarizer 324 allows only light waves vibrating in a specific direction to pass through while blocking all others. When light is emitted fromPATENTAttorney Docket No.: 44025989WO01the OLE material 112, the light waves typically vibrate in multiple directions, making it unpolarized. When this light encounters the polarizer 324, which consists of molecules aligned in a particular direction, only the light waves that oscillates parallel to these molecules are transmitted. The perpendicular light waves are absorbed or scattered, effectively reducing the light to a single plane of vibration. This process transforms unpolarized light into linearly polarized light, which reduces glare.

[0043] Figure 4 is a schematic, cross-sectional view of a sub-pixel circuit 400, according to one or more embodiments. The sub-pixel circuit 400 is similar to the subpixel circuit 200 and the sub-pixel circuit 300 shown in Figures 2 and 3 respectively, and includes one or more of the aspects, features, components, properties, and / or operations thereof.

[0044] In one or more embodiments, the sub-pixel circuit 400 includes black layer 222 disposed over the portion of the upper surface of the upper structure 110B of the overhang structure 110 exposed by the opening 150 of the first TFE layer 116. The black layer 222 extends onto the sidewalls 151 of first TFE layer 116 defining the opening 150 and extend on to at least a portion of the uppermost surface 152 of the first TFE layer 116. In one or more embodiments, the black layer 222 is deposited suing a chemical vapor deposition (CVD) process or a physical vapor deposition (PVD) process. The black layer 222 includes carbon, chromium carbonitride (CrCN), chromium nitride (CrN), ora combination thereof. The black layer 222 absorbs ambient light traveling through the sub-pixel circuit 400. The black layer 222 helps define the sub-pixels 108 and improves the overall image quality of the sub-pixel circuit 400.

[0045] A global encapsulation layer 118 is deposited over the black layer 222 and the first TFE layer 116. The global encapsulation layer 118 layers covers the overhang structures 110, the black layer 222, and the first TFE layer 116. The global encapsulation layer fills the sub-pixels 108. In one or more embodiments, the global encapsulation layer is deposited within the opening 150 and fills the gap between the upper surface of the upper structure 110B of the overhang structures 110 and the first TFE layer 116. In one or more embodiments, the global encapsulation layer 118 layer is an inkjet layer. In one or more embodiments, the global encapsulation layer 118 is planarized.PATENTAttorney Docket No.: 44025989WO01

[0046] A second TFE layer 120 is deposited over the global encapsulation layer 118. In one or more embodiments, the second TFE layer 120 and the first TFE layer 116 are formed of the same material. In one or more embodiments, the upper surface of the second TFE layer 120 is planarized. A polarizer 324 is deposited over the second TFE layer 120. The polarizer 324 filters the light emitted by the OLE material 112 of each sub-pixel 108. In one or more embodiments, the polarizer is laminated. The polarizer 324 allows only light waves vibrating in a specific direction to pass through while blocking all others. When light is emitted from the OLE material 112, the light waves typically vibrate in multiple directions, making it unpolarized. When this light encounters the polarizer 324, which consists of molecules aligned in a particular direction, only the light waves that oscillates parallel to these molecules are transmitted. The perpendicular light waves are absorbed or scattered, effectively reducing the light to a single plane of vibration. This process transforms unpolarized light into linearly polarized light, which reduces glare.

[0047] Figure 5 is a schematic, cross-sectional view of a sub-pixel circuit 500, according to one or more embodiments. The sub-pixel circuit 500 is similar to the subpixel circuit 100 shown in Figure 1, and includes one or more of the aspects, features, components, properties, and / or operations thereof.

[0048] Each sub-pixel 108 includes a first thin film encapsulation (TFE) layer 116. The first TFE layer 116 may be or may correspond to a local passivation layer. The first TFE layer 116 of a respective sub-pixel is disposed over the cathode 114 (and OLE material 112) with the first TFE layer 116 extending under at least a portion of each of the overhang structures 110 and along a sidewall of each of the overhang structures 110. The first TFE layer 116 is disposed over the cathode 114 and over at least the sidewall 111 of the lower structure 110A. In some embodiments, which can be combined with other embodiments described herein, the first TFE layer 116 is disposed over the upper sidewall 113 of the upper structure 110B. The first TFE layer 116 includes the non-conductive inorganic material, such as the silicon-containing material. The silicon-containing material may include SisN4 containing materials. In one or more embodiments, the first TFE layer 116 is deposited using a chemical vapor deposition (CVD) process.PATENTAttorney Docket No.: 44025989WO01

[0049] A gap fill layer 518 is deposited over the overhang structures 110 and the first TFE layer 116. In one or more embodiments, the upper surface of the gap fill layer 518 is planarized. In one or more embodiment, the gapfill layer includes a silicon based polymer, a transparent conductive oxide, aluminum oxide, or a combination thereof. The gap fill layer 518 is deposited using a CVD or an ALD deposition process. A blackening material 122 is patterned on the gap fill layer 518, to align over the overhang structures 110. In one or more embodiments, the blackening material 122 is deposited on the using an inkjet printing (IJP) process. In one or more embodiments the blackening material includes a black ink material. A global encapsulation layer 118 is deposited over the blackening material 122 and the gap fill layer 518. The global encapsulation layer 118 layers covers the overhang structures 110, the blackening material 122, and the gap fill layer 518. In one or more embodiments, the global encapsulation layer 118 layer is an ink jet layer. In one or more embodiments, the global encapsulation layer 118 is planarized. The blackening material 122 absorbs ambient light traveling through the sub-pixel circuit 500. The blackening material 122 helps define the sub-pixels 108 and improves the overall image quality of the sub-pixel circuit 500. In one or more embodiments, the blackening material 122 is deposited using a slit coating process. In one or more embodiments, the blackening material 122 is deposited using a lithography patterning process.

[0050] A second TFE layer 120 is deposited over the global encapsulation layer 118. In one or more embodiments, the second TFE layer 120 and the first TFE layer 116 are formed of the same material. In one or more embodiments, the upper surface of the second TFE layer 120 is planarized. Color filters 124 are patterned to align over the OLE material 112 of each sub-pixel 108. Each color filter 124 aligns over a corresponding OLE material 112 (e.g., a red color filter will align over a OLE material 112, a green color filter will align over a green OLE material 112, a blue color filter will align over a blue OLE material 112). In one or more embodiments, one or more of the sub-pixels 108 include an OLE material configured to emit a white or yellow light. One or more color filters 124 are aligned with each sub-pixel 108 emitting a white or yellow light. As the light emitted y the OLE material 112 within each sub-pixel 108 travels through the color filter 124, the color filter 124 changes the color of the light emitted through the color filter 124. The color filters 124 are operable to provide an increasedPATENTAttorney Docket No.: 44025989WO01brightness of the colored light emitted from the final display device. In one or more embodiments, adjacent color filters 124 may overlap over the overhang structures 110. An outer encapsulation layer 130 is deposited over the color filters 124 in order to cover and protect the color filters 124 and the sub-pixel circuit 500.

[0051] Figure 6 is a schematic, cross-sectional view of a sub-pixel circuit 600, according to one or more embodiments. The sub-pixel circuit 600 is similar to the subpixel circuit 100 and the sub-pixel circuit 500 shown in Figures 1 and 5 respectively, and includes one or more of the aspects, features, components, properties, and / or operations thereof.

[0052] In one or more embodiments, the sub-pixel circuit 600 includes a a black layer 222 is patterned on the gap fill layer 518, to align over the overhang structures 110. In one or more embodiments, the black layer 222 is deposited during a chemical vapor deposition (CVD) process or a physical vapor deposition (PVD) process. The black layer 222 includes carbon, chromium carbonitride (CrCN), chromium nitride (CrN), or a combination thereof. The black layer 222 absorbs ambient light traveling through the sub-pixel circuit 600. The black layer 222 helps define the sub-pixels 108 and improves the overall image quality of the sub-pixel circuit 600. A global encapsulation layer 118 is deposited over the black layer 222 and the gap fill layer 518. The global encapsulation layer 118 layers covers the overhang structures 110, the black layer 222, and the gap fill layer 518. In one or more embodiments, the global encapsulation layer 118 layer is an ink jet layer. In one or more embodiments, the global encapsulation layer 118 is planarized.

[0053] A second TFE layer 120 is deposited over the global encapsulation layer 118. In one or more embodiments, the second TFE layer 120 and the first TFE layer 116 are formed of the same material. In one or more embodiments, the upper surface of the second TFE layer 120 is planarized. Color filters 124 are patterned to align over the OLE material 112 of each sub-pixel 108. Each color filter 124 aligns over a corresponding OLE material 112 (e.g., a red color filter will align over a red OLE material 112, a green color filter will align over a green OLE material 112, a blue color filter will align over a blue OLE material 112). In one or more embodiments, one or more of the sub-pixels 108 include an OLE material configured to emit a white or yellowPATENTAttorney Docket No.: 44025989WO01light. One or more color filters 124 are aligned with each sub-pixel 108 emitting a white or yellow light. As the light emitted y the OLE material 112 within each sub-pixel 108 travels through the color filter 124, the color filter 124 changes the color of the light emitted through the color filter 124. The color filters 124 are operable to provide an increased brightness of the colored light emitted from the final display device. In one or more embodiments, adjacent color filters 124 may overlap over the overhang structures 110. An outer encapsulation layer 130 is deposited over the color filters 124 in order to cover and protect the color filters 124 and the sub-pixel circuit 500.

[0054] Figure 7 is a schematic, cross-sectional view of a sub-pixel circuit 700, according to one or more embodiments. The sub-pixel circuit 700 is similar to the subpixel circuit 300 and the sub-pixel circuit 500 shown in Figures 3 and 5 respectively, and includes one or more of the aspects, features, components, properties, and / or operations thereof.

[0055] A gap fill layer 518 is deposited over the overhang structures 110 and the first TFE layer 116. In one or more embodiments, the upper surface of the gap fill layer 518 is planarized. In one or more embodiment, the gapfill layer includes a silicon based polymer, a transparent conductive oxide, aluminum oxide, or a combination thereof. The gap fill layer 518 is deposited using a CVD or an ALD deposition process. A blackening material 122 is patterned on the gap fill layer 518, to align over the overhang structures 110. In one or more embodiments, the blackening material 122 is deposited on the using an inkjet printing (IJP) process. In one or more embodiments the blackening material includes a black ink material. A global encapsulation layer 118 is deposited over the blackening material 122 and the gap fill layer 518. The blackening material 122 absorbs ambient light traveling through the sub-pixel circuit 700. The blackening material 122 helps define the sub-pixels 108 and improves the overall image quality of the sub-pixel circuit 700. The global encapsulation layer 118 layers covers the overhang structures 110, the blackening material 122, and the gap fill layer 518. In one or more embodiments, the global encapsulation layer 118 layer is an ink jet layer. In one or more embodiments, the global encapsulation layer 118 is planarized.PATENTAttorney Docket No.: 44025989WO01

[0056] A second TFE layer 120 is deposited over the global encapsulation layer 118. In one or more embodiments, the second TFE layer 120 and the first TFE layer 116 are formed of the same material. In one or more embodiments, the upper surface of the second TFE layer 120 is planarized. A polarizer 324 is deposited over the second TFE layer 120. The polarizer 324 filters the light emitted by the OLE material 112 of each sub-pixel 108. In one or more embodiments, the polarizer is laminated. The polarizer 324 allows only light waves vibrating in a specific direction to pass through while blocking all others. When light is emitted from the OLE material 112, the light waves typically vibrate in multiple directions, making it unpolarized. When this light encounters the polarizer 324, which consists of molecules aligned in a particular direction, only the light waves that oscillates parallel to these molecules are transmitted. The perpendicular light waves are absorbed or scattered, effectively reducing the light to a single plane of vibration. This process transforms unpolarized light into linearly polarized light, which reduces glare.

[0057] Figure 8 is a schematic, cross-sectional view of a sub-pixel circuit 800, according to one or more embodiments. The sub-pixel circuit 800 is similar to the subpixel circuit 400 and the sub-pixel circuit 500 shown in Figures 4 and 5 respectively, and includes one or more of the aspects, features, components, properties, and / or operations thereof.

[0058] In one or more embodiments, the sub-pixel circuit 600 includes a black layer 222 is patterned on the gap fill layer 518, to align over the overhang structures 110. In one or more embodiments, the black layer 222 is deposited during a chemical vapor deposition (CVD) process or a physical vapor deposition (PVD) process. The black layer 222 includes carbon, chromium carbonitride (CrCN), chromium nitride (CrN), or a combination thereof. The black layer 222 absorbs ambient light traveling through the sub-pixel circuit 800. The black layer 222 helps define the sub-pixels 108 and improves the overall image quality of the sub-pixel circuit 800. A global encapsulation layer 118 is deposited over the black layer 222 and the gap fill layer 518. The global encapsulation layer 118 layers covers the overhang structures 110, the black layer 222, and the gap fill layer 518. In one or more embodiments, the global encapsulationPATENTAttorney Docket No.: 44025989WO01layer 118 layer is an ink jet layer. In one or more embodiments, the global encapsulation layer 118 is planarized.

[0059] A second TFE layer 120 is deposited over the global encapsulation layer 118. In one or more embodiments, the second TFE layer 120 and the first TFE layer 116 are formed of the same material. In one or more embodiments, the upper surface of the second TFE layer 120 is planarized. A polarizer 324 is deposited over the second TFE layer 120. The polarizer 324 filters the light emitted by the OLE material 112 of each sub-pixel 108. In one or more embodiment, the polarizer is laminated. The polarizer 324 allows only light waves vibrating in a specific direction to pass through while blocking all others. When light is emitted from the OLE material 112, the light waves typically vibrate in multiple directions, making it unpolarized. When this light encounters the polarizer 324, which consists of molecules aligned in a particular direction, only the light waves that oscillates parallel to these molecules are transmitted. The perpendicular light waves are absorbed or scattered, effectively reducing the light to a single plane of vibration. This process transforms unpolarized light into linearly polarized light, which reduces glare.

[0060] In one or more embodiments, a method of forming the sub-pixel circuit 100, the sub-pixel circuit 200, the sub-pixel circuit 300, the sub-pixel circuit 400, the subpixel circuit 500, the sub-pixel circuit 600, the sub-pixel circuit 700, the sub-pixel circuit 800, or a combination thereof includes forming adjacent overhang structures 110 over the substrate using a photolithography process. The OLE material 112, the cathode 114, and the first TFE layer 116 are disposed over the metal layer 104, i.e., anode, between the overhang structure 110 using an evaporation deposition process. The OLE material 112 and the cathode 114 disposed over the upper structure 110B of the overhang structure 110 are removed using an etching process. The etching process forms a gap between the upper structure 110B of the overhang structure 110 and the first TFE layer 116. In one or more embodiments, the black layer 222 is disposed over the overhang structures 110 and the first TFE layer 116 using a photolithography process. In one or more embodiments, prior to the black layer 222 or the blackening material 122 being disposed, a gap fill layer 518 is disposed over each sub-pixel 108. In one or more embodiments, the gap fill layer 518 is planarized using a CMP process.PATENTAttorney Docket No.: 44025989WO01In one or more embodiments, the blackening material 122 is disposed over the overhang structure 110 and within the gap using an IJP process. The global encapsulation layer 118 is disposed over each sub-pixel 108 circuit using an IJP process. In one or more embodiments, the global encapsulation layer 118 is planarized using a CMP process. The second TFE layer 120 is disposed over the global encapsulation layer 118 using a deposition process. In one or more embodiments, the second TFE layer 120 is planarized using a CMP process. The color filters 124, the outer encapsulation layer 130, and / or the polarizer are deposited over the global encapsulation layer 118.

[0061] Benefits of the present disclosure include increased pixels-per-inch, increased device performance, increased device image resolution, decreased cost, and decreased maintenance.

[0062] It is contemplated that one or more aspects disclosed herein may be combined. As an example, one or more aspects, features, components, operations and / or properties of the sub-pixel circuit 100, the sub-pixel circuit 200, the sub-pixel circuit 300, the sub-pixel circuit 400, the sub-pixel circuit 500, the sub-pixel circuit 600, the sub-pixel circuit 700, and / or the sub-pixel circuit 800 may be combined. Moreover, it is contemplated that one or more aspects disclosed herein may include some or all of the aforementioned benefits.

[0063] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

PATENTAttorney Docket No.: 44025989WO01What is claimed is:

1. A sub-pixel circuit, comprising:a substrateoverhang structures disposed over the substrate, the overhang structures defining sub-pixels of the sub-pixel circuit, the overhang structures including an upper structure disposed over a lower structure;a plurality of sub-pixels, each sub-pixel comprising:an anode;an organic light-emitting (OLE) material disposed over and in contact with the anode; anda cathode disposed over the OLE material; andan encapsulation layer disposed over the cathode; and a light absorbing material disposed over the upper structure of the overhang structures.

2. The sub-pixel of claim 1 , wherein the light absorbing material comprises a black ink material.

3. The sub-pixel of claim 1 , wherein the light absorbing material comprises carbon, chromium carbonitride (CrCN), chromium nitride (CrN), or a combination thereof.

4. The sub-pixel of claim 1 , wherein a gap fill material is disposed between the upper structure of the overhang structures and the light absorbing material.

5. The sub-pixel of claim 1 , wherein the light absorbing material contacts the upper structure of the overhang structures.

6. The sub-pixel of claim 1 , further comprising:color filters aligned over the OLE material of each sub-pixel.

7. The sub-pixel of claim 6, wherein the color filters overlap with one another.PATENTAttorney Docket No.: 44025989WO018. The sub-pixel of claim 1 , further comprising:a polarizer.

9. A sub-pixel circuit, comprising:a substrateoverhang structures disposed over the substrate, the overhang structures defining sub-pixels of the sub-pixel circuit, the overhang structures including an upper structure disposed over a lower structure;a plurality of sub-pixels, each sub-pixel comprising:an anode;an organic light-emitting (OLE) material disposed over and in contact with the anode; anda cathode disposed over the OLE material; anda first thin film encapsulation (TFE) layer disposed over the cathode; a light absorbing material disposed over the upper structure of the overhang structures;a global encapsulation layer deposited over the first TFE layer and the light absorbing material; anda second TFE layer deposited over the global encapsulation layer.

10. The sub-pixel of claim 9, wherein the light absorbing material comprises a black ink material.

11. The sub-pixel of claim 9, wherein the light absorbing material comprises carbon, chromium carbonitride (CrCN), chromium nitride (CrN), or a combination thereof.

12. The sub-pixel of claim 9, wherein a gap fill material is disposed between the upper structure of the overhang structures and the light absorbing material.PATENTAttorney Docket No.: 44025989WO0113. The sub-pixel of claim 9, wherein the light absorbing material contacts the upper structure of the overhang structures.

14. The sub-pixel of claim 9, further comprising:color filters disposed over the second TFE layer, wherein the color filters are aligned over the OLE material of each sub-pixel.

15. The sub-pixel of claim 14, wherein the color filters overlap with one another.

16. The sub-pixel of claim 9, further comprising:a polarizer disposed over the second TFE layer.

17. A sub-pixel circuit, comprising:a substrateoverhang structures disposed over the substrate, the overhang structures defining sub-pixels of the sub-pixel circuit the overhang structures including an upper structure disposed over a lower structure;a plurality of sub-pixels, each sub-pixel comprising:an anode;an organic light-emitting (OLE) material disposed over and in contact with the anode; anda cathode disposed over the OLE material; anda first thin film encapsulation (TFE) layer disposed over the cathode; a light absorbing material disposed over the upper structure of the overhang structures;a global encapsulation layer deposited over the first TFE layer and the light absorbing material;a second TFE layer deposited over the global encapsulation layer;color filters patterned over the second TFE layer to align over the OLE material of each sub-pixel; andan outer encapsulation layer disposed over the color filters.PATENTAttorney Docket No.: 44025989WO0118. The sub-pixel of claim 17, wherein the light absorbing material comprises a black ink material.

19. The sub-pixel of claim 17, wherein the light absorbing material comprises carbon, chromium carbonitride (CrCN), chromium nitride (CrN), or a combination thereof.

20. The sub-pixel of claim 17, wherein a gap fill material is deposited between the upper structure of the overhang structures and the light absorbing material.

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