OLED micro-resonant cavity structure and manufacturing method thereof

Abstract

The invention discloses an OLED micro-resonant cavity structure and a manufacturing method thereof. The method comprises the following steps: providing a substrate; forming an insulating layer on the substrate; forming a metal reflecting region on the insulating layer by means of grooving and metal deposition, and forming a polished reflecting surface on the surface of the metal reflecting region by polishing; forming a cavity length adjusting layer covering the metal reflection region; a light-emitting layer corresponding to the metal reflection area is formed above the cavity length adjusting layer, and after original light emitted by the light-emitting layer passes through the cavity length adjusting layer, constructive interference is formed between the original light and reflected light of the polishing reflection face of the corresponding metal reflection area. According to the invention, the metal reflection region is formed by skillfully using a Damascus process, the reflection surface is flatter and smoother through polishing, the reflectivity is improved, the power consumption is reduced, and the yield is improved; the cavity length of the micro-resonant cavity is determined by the distance between the polishing reflecting surface and the light-emitting layer, and the accurate cavity length of the micro-resonant cavity can be controlled more easily by controlling the polishing reflecting surface to be smooth and consistent in height through polishing.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to an OLED micro-resonance cavity structure and a manufacturing method thereof. Background Art

[0002] Organic Light Emitting Diode (OLED) has the characteristics of self-luminescence, simple structure, ultra-thin, full color, high brightness, high contrast, fast response speed, wide viewing angle, low power consumption and flexible display, and is the new generation of main force in the field of display technology. Silicon-based OLED has become a new display device in the fields of augmented reality and virtual reality due to its high brightness, low power consumption and rich color display.

[0003] In the production process of OLED, a single-layer structure with uniform thickness of BRG (blue light, red light, green light) is generally used, but the light color of this structure is impure and the light extraction efficiency is not high. The microcavity resonance structure can effectively improve the light purity and light extraction efficiency of the device. However, the existing microcavity resonance structure mainly forms cavity lengths of different thicknesses by etching the silicon dioxide layer, but the etched surface is not smooth and cannot be polished. In addition, the process is complex, the thickness of the microcavity is not easy to control, the loss of metal Al in the reflective layer is large, the reflectivity is low, the brightness of the device decreases, the light purity decreases, and the yield loss is high. Summary of the invention

[0004] The main purpose of the present invention is to provide an OLED micro-resonance cavity structure and a manufacturing method thereof which can effectively control the cavity length of the OLED micro-resonance cavity and has high reflectivity.

[0005] The technical solution adopted by the present invention is: Provided is a method for manufacturing an OLED micro-resonance cavity structure, comprising: providing a substrate; forming an insulating layer on the substrate; A metal reflection area is formed on the insulating layer by groove engraving and metal deposition, and a surface of the metal reflection area is polished to form a polished reflection surface; forming a cavity length adjustment layer covering the metal reflection area; A light emitting layer corresponding to the metal reflective area is formed above the cavity length adjustment layer. After passing through the cavity length adjustment layer, the original light emitted by the light emitting layer forms constructive interference with the reflected light of the polished reflective surface of the corresponding metal reflective area.

[0006] Continuing with the above technical solution, the steps for forming the metal reflective area specifically include: forming a cushioning layer and an anti-reflective layer located above the insulating layer; forming a mask layer covering the anti-reflective layer; etching a groove using the mask layer as a mask and the insulating layer as a reference layer; removing the mask layer; forming a metal reflective layer on the groove; and polishing the metal reflective layer to form a polished reflective surface.

[0007] Following the above technical solution, in the process of forming the metal reflective area, an isolation layer is first formed on the groove, and then a metal reflective layer is formed on the isolation layer.

[0008] Following the above technical solution, at least three metal reflection areas are formed on the insulating layer, and the polished reflection surfaces of different metal reflection areas have different heights; and the corresponding first light-emitting layer, second light-emitting layer and third light-emitting layer are formed above the cavity length adjustment layer.

[0009] Following the above technical solution, the steps of forming the three metal reflection areas specifically include: Forming a first anti-reflection layer on the insulating layer, forming a first mask layer covering the anti-reflection layer; etching a first groove using the first mask layer as a mask and the insulating layer as a reference layer; removing the first mask layer, forming a first metal reflection layer on the first groove, polishing the first metal reflection layer to form a first, forming a first polished reflection surface, and completing the production of a first metal reflection area; Forming a first cavity length adjustment layer covering the first metal reflection area, forming a second anti-reflection layer located on the first cavity length adjustment layer, and forming a second mask layer covering the second anti-reflection layer; etching a second groove using the second mask layer as a mask and the insulating layer as a reference layer; removing the second mask layer, forming a second metal reflection layer on the second groove, polishing the second metal reflection layer to form a second polished reflection surface, and completing the production of the second metal reflection area; Forming a second cavity length adjustment layer on the second metal reflection area, forming a third anti-reflection layer located on the second cavity length adjustment layer, and forming a third mask layer covering the third anti-reflection layer; etching a third groove using the third mask layer as a mask and the insulating layer as a reference layer; removing the third mask layer, forming a third metal reflection layer on the third groove, polishing the third metal reflection layer to form a third polished reflection surface, and completing the production of the third metal reflection area; Among them, the heights of the three polished reflective surfaces are different.

[0010] In accordance with the above technical solution, the method further includes the following steps: after the metal reflective region is formed, an electrode connection column is formed in the cavity length adjustment layer above the metal reflective region, and the electrode connection column is connected to the metal reflective region.

[0011] The present invention also provides an OLED micro-resonance cavity structure, comprising: substrate; an insulating layer, located on the substrate; At least one metal reflection area is located on the insulating layer, the metal reflection area is formed by groove engraving and metal deposition, and the surface of the metal reflection area is polished to form a polished reflection surface; A cavity length adjustment layer covering the metal reflection area; The light-emitting layer is located above the cavity length adjustment layer. The original light emitted by the light-emitting layer forms constructive interference with the reflected light of the polished reflective surface of the corresponding metal reflective area after passing through the cavity length adjustment layer.

[0012] Following the above technical solution, at least three metal reflection areas are included, and corresponding R light-emitting layer, G light-emitting layer and B light-emitting layer are also arranged above the cavity length adjustment layer, and the heights of the polished reflection surfaces of different metal reflection areas are different.

[0013] According to the above technical solution, an electrode connection column is provided in the cavity length adjustment layer and is connected to the metal reflection area.

[0014] The present invention also provides an organic light emitting diode, comprising the OLED micro-resonance cavity structure described in the above technical solution, and at least one semi-transparent conductive layer is provided thereon, and the metal reflective area of ​​the OLED micro-resonance cavity structure serves as another conductive layer, and the polarities of the two conductive layers are different.

[0015] The beneficial effects of the present invention are as follows: the present invention forms a metal reflection area by grooving and depositing metal below the micro-resonance cavity of the organic light emitting diode OLED, and produces a polished reflection surface by polishing on the surface of the metal reflection area, and covers the polished reflection surface with a cavity length adjustment layer. The original light emitted by the light emitting layer forms constructive interference with the reflected light of the polished reflection surface after passing through the cavity length adjustment layer. The unexpected effect is that the present invention cleverly forms the metal reflection area with the help of the Damascus process, and the reflection surface is made flatter, smoother and has a higher reflectivity by polishing, thereby improving the brightness of the emitted light, reducing power consumption and improving the yield; and the distance between the polished reflection surface and the light emitting layer determines the cavity length of the micro-resonance cavity, and the polished reflection surface is controlled to be smooth and highly consistent by polishing, so that the precise cavity length of the micro-resonance cavity can be more easily controlled.

[0016] Furthermore, when manufacturing a full-color organic light-emitting diode OLED, at least three metal reflection areas are formed, and the cavity length of the corresponding micro-resonance cavity is adjusted by controlling the different heights of the polished reflection surfaces of the three metal reflection areas, so that constructive interference of light of different colors in the micro-resonance cavity can be achieved.

[0017] Furthermore, when manufacturing the metal reflective area, the insulating layer is used as a reference layer to etch the groove, which can better control the depth of the groove and reduce the difficulty of the process.

[0018] Furthermore, by forming an anti-reflection coating at the bottom of the metal reflective area, it is possible to effectively prevent the standing wave effect generated during mask exposure from affecting the dissolution effect of the exposed portion.

[0019] Furthermore, by forming an isolation layer below the metal reflective region, it is possible to effectively prevent the metal in the metal reflective region from migrating into the substrate to cause leakage or light unevenness.

[0020] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 is a flow chart of a method for manufacturing an OLED micro-resonant cavity structure according to an embodiment of the present invention; Figure 2A-2G It is a schematic cross-sectional structure diagram of an OLED micro-resonance cavity structure during the manufacturing process according to an embodiment of the present invention; Figure 3A-3G It is a schematic cross-sectional structure diagram of a full-color OLED micro-resonant cavity structure during the manufacturing process of an embodiment of the present invention; Figure 4A-4G It is a schematic cross-sectional structure diagram of a full-color OLED micro-resonant cavity structure during the manufacturing process of an embodiment of the present invention; Figure 5A-5F It is a schematic diagram of the cross-sectional structure of an organic light emitting diode OLED during the manufacturing process according to an embodiment of the present invention.

[0023] In the figure: 101, substrate; 102, insulating layer; 103, pad layer; 104, first anti-reflection layer; 105, first mask layer; 106, first isolation layer; 107, first metal reflection layer; RZ, metal reflection zone; 108, first cavity length adjustment layer; 109, second anti-reflection layer; 110, second mask layer; 111, second isolation layer; 112, second metal reflection layer; 113, second cavity length adjustment layer; 114, third anti-reflection layer; 115, third mask layer; 116, third isolation layer; 117, third metal reflection layer; 118, third cavity length adjustment layer; 119, fourth anti-reflection layer; 120, fourth mask layer; 121, via hole; 122, electrode connecting column; 123, light-emitting layer; 124, semi-transparent conductive layer; 125, CMOS device. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0025] It should be noted that the illustrations provided in the embodiments of the present invention are only used to illustrate the basic concept of the present invention in a schematic manner. Therefore, the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout type may also be more complicated.

[0026] In the present invention, it is also necessary to explain that, if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, if the terms "first" and "second" appear, they are only used for description and distinction purposes, and cannot be understood as indicating or implying relative importance.

[0027] In addition, it should be noted that the features of the various embodiments of the present invention may be combined or combined in part or in whole, and may interact and operate in different ways as will be appreciated by those skilled in the art. Each embodiment may be implemented independently of one another, or in an associated relationship.

[0028] This patent cleverly uses the Damascus process to form a metal reflective area, and polishes the surface of the metal reflective area by polishing to form a polished reflective surface. The polished reflective surface serves as the bottom reflective surface of the micro-resonance cavity. It is flat and smooth, with extremely high reflectivity, and the distance from it to the light-emitting layer, that is, the cavity length of the micro-resonance cavity, can be accurately controlled.

[0029] like Figure 1 As shown, the method for manufacturing the OLED micro-resonance cavity structure of this embodiment mainly includes the following steps: S1. providing a substrate; S2, forming an insulating layer on the substrate; S3, forming a metal reflection area on the insulating layer by groove engraving and metal deposition, and polishing the surface of the metal reflection area to form a polished reflection surface; S4, forming a cavity length adjustment layer covering the metal reflection area; S5. A light-emitting layer corresponding to the metal reflective area is formed above the cavity length adjustment layer. After the original light emitted by the light-emitting layer passes through the cavity length adjustment layer, it forms constructive interference with the reflected light of the polished reflective surface of the corresponding metal reflective area.

[0030] The micro-resonance cavity of the OLED is formed between the polished reflective surface, the cavity length adjustment layer and the light-emitting layer, that is, light forms constructive interference in the micro-resonance cavity. Since the polished reflective layer formed by polishing in the present invention has a smooth surface, the reflection height of the reflective surface can be guaranteed to be consistent and the reflection efficiency is high, thereby ensuring the accuracy of the cavity length of the micro-resonance cavity.

[0031] Please refer to Figure 2A In step S1, the substrate 101 can be a silicon substrate or a silicon dioxide substrate. In step S2, an insulating layer 102 is formed on the substrate 101. The insulating layer 102 can be silicon nitride SiN, and a plasma enhanced chemical vapor deposition PECVD deposition process can be used. The insulating layer 102 can be used as a reference layer when a metal reflective region is subsequently formed, so as to better control the thickness of the metal reflective region. Silicon oxynitride SiON can also be formed on the insulating layer 102 as a bottom anti-reflective coating BARC, which can prevent the standing wave effect from being generated during the subsequent exposure of the photoresist PR, affecting the dissolution effect of the exposed part of the positive photoresist.

[0032] Please refer to Figure 2A-2G The steps for forming the metal reflection area specifically include: S31. Form a cushioning layer 103 and a first anti-reflection layer 104 located on the insulating layer 102. The material of the anti-reflection layer can be silicon oxynitride SiON, which serves as a bottom anti-reflection coating BARC to prevent the standing wave effect from being generated during the subsequent exposure of the photoresist PR, thereby affecting the dissolution effect of the exposed part of the positive photoresist. Among them, the cushioning layer 103 is mainly used to provide space for etching the groove. The material of the cushioning layer 103 and the cavity length adjustment layer can be the same or different. In the embodiment of the present invention, the two are selected to have the same material, such as silicon dioxide.

[0033] S32, covering the first anti-reflection layer 104 with a first mask layer 105, the first mask layer 105 may be a photoresist PR, and coating a layer of positive photoresist thereon, defining the position and size of the metal reflection area by the mask, and then transferring the pattern on the mask to the photoresist layer PR by exposure, thereby forming the first mask layer 105; S33, using the first mask layer 105 as a mask and the insulating layer 102 as a reference layer, etching downward the first anti-reflection layer 104, the padding layer 103, the insulating layer 102, and even reaching the substrate 101 to form a first groove of a certain depth, and the first groove may be etched by dry etching; S34, removing the first mask layer 105 after the first groove is formed; S35, forming a first metal reflective layer 107 on the first groove, and specifically, various physical vapor deposition (PVD) processes may be used to deposit aluminum Al on the groove; in order to prevent the first metal reflective layer 107 from migrating into the silicon substrate to cause leakage or light unevenness, a first isolation layer 106 may be first formed at the bottom of the first groove, and various physical vapor deposition (PVD) processes may be used to deposit titanium Ti or titanium nitride TiN on the first groove; S36 , polishing the first metal reflective layer 107 to form a polished reflective surface, thereby completing the production of a metal reflective zone RZ. Specifically, chemical mechanical polishing (CMP) can be used to remove the redundant metal reflective layer, and the thickness of the first metal reflective layer 107 can be controlled according to the position of the insulating layer 102 .

[0034] In step S4, a first cavity length adjustment layer 108 is formed to cover the metal reflective region. The first cavity length adjustment layer 108 is mainly used for light transmission and is used to form the main body of the micro-resonance cavity. The material of the first cavity length adjustment layer 108 may be silicon dioxide SiO2.

[0035] In step S5, an organic light-emitting layer may be formed on the first cavity length adjustment layer 108 by using a suitable process technology such as evaporation or inkjet printing. The organic light-emitting layer may include a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer. The structure of the organic light-emitting layer may be changed into various shapes commonly known to those skilled in the art.

[0036] In a preferred embodiment of the present invention, at least three metal reflection areas can be formed. The polished reflection surfaces of different metal reflection areas have different heights, and a corresponding first light-emitting layer, a second light-emitting layer and a third light-emitting layer are formed above the cavity length adjustment layer. The three light-emitting layers have different light-emitting colors, which can be red R, green G and blue B. The order of the three colors can be set as needed.

[0037] like Figure 2A-2G , Figures 3A-3G , Figures 4A-4G : is a diagram of the formation process of three metal reflection zones. In this embodiment, the three metal reflection zones RZ correspond to the luminous zones of red R, green G and blue B respectively. The formation process of the three metal reflection zones specifically includes the following steps: The production of the first metal reflection area can refer to Figure 2A-2G, forming a padding layer 103 and a first anti-reflection layer 104 located on the insulating layer 102, forming a first mask layer 105 covering the first anti-reflection layer 104; using the first mask layer 105 as a mask and the insulating layer 102 as a reference layer, etching the first groove; removing the first mask layer 105, forming a first metal reflection layer 107 on the first groove, polishing the first metal reflection layer 107 to form a first polished reflection surface, thereby completing the production of the first metal reflection area. In order to prevent the metal reflection layer from migrating to the substrate 101 to cause leakage or uneven light, a first isolation layer 106 can be formed at the bottom of the first groove.

[0038] The preparation of the second metal reflection area can refer to Figures 3A-3G , forming a first cavity length adjustment layer 108 covering the first metal reflection area, the material of the first cavity length adjustment layer 108 can be selected from silicon dioxide; forming a second anti-reflection layer 109 located on the first cavity length adjustment layer 108, forming a second mask layer 110 covering the second anti-reflection layer 109; using the second mask layer 110 as a mask and the insulating layer 102 as a reference layer, etching the second groove; removing the second mask layer 110, forming a second metal reflection layer 112 on the second groove, polishing the second metal reflection layer 112 to form a second polished reflection surface, and completing the production of the second metal reflection area. In order to prevent the metal reflection layer from migrating to the first cavity length adjustment layer 108 to cause leakage or light unevenness, a second isolation layer 111 can be first formed at the bottom of the second groove.

[0039] The preparation of the third metal reflection area can refer to Figures 4A-4G , forming a second cavity length adjustment layer 113 on the second metal reflection area, the material of the second cavity length adjustment layer 113 can be selected from silicon dioxide, which is the same as the material of the first cavity length adjustment layer 108 of the second metal reflection area; forming a third anti-reflection layer 114 located on the second cavity length adjustment layer 113, forming a third mask layer 115 covering the third anti-reflection layer 114; using the third mask layer 115 as a mask and the insulating layer 102 as a reference layer, etching the third groove; removing the third mask layer 115, forming a third metal reflection layer 117 on the third groove, polishing the third metal reflection layer 117, forming a third polished reflection surface, and completing the production of the third metal reflection area. In order to prevent the metal reflection layer from migrating to the second cavity length adjustment layer 113 to cause leakage or light unevenness, a third isolation layer 116 can be first formed at the bottom of the third groove.

[0040] In order to form a micro-resonant cavity corresponding to the third metal reflective region, a third cavity length adjustment layer 118 needs to be formed above the third metal reflective region.

[0041] The polished reflection surfaces of the three metal reflection areas have different heights, which are used to control the cavity length of the micro-resonance cavity.

[0042] Specifically, in the prior art, if you want to form a micro-resonance cavity with multiple colors, you mainly need to directly deposit a light-transmitting layer on the metal of the reflective layer, and then form a light-transmitting layer of different thicknesses by etching (the thickness of the light-transmitting layer determines the cavity length of the micro-resonance cavity). Because the thickness of the light-transmitting layer is different, it is impossible to polish the top of the surface, resulting in an uneven cavity, inconsistent reflection height, and low reflectivity, which makes it impossible to ensure a smooth cavity and precise cavity length. However, the original light emitted by the light-emitting layer of this patent forms constructive interference with the reflected light of the polished reflective surface after passing through the cavity length adjustment layer. Since the wavelengths of red light, green light, and blue light are different, the cavity length of the micro-resonance cavity corresponds to the desired wavelength of light. The micro-resonance distance between the polished reflective surface and the light-emitting layer determines the cavity length of the micro-resonance cavity. The three metal reflective areas in this embodiment are formed with the insulating layer as the reference layer. Therefore, the bottoms of the three metal reflective areas are on the same horizontal plane. When the last metal reflective area is completed, the surface of the cavity length adjustment layer covering the three metal reflective areas is also on the same horizontal plane (no need to etch to form different thicknesses, but it can be uniformly polished to be smoother). Therefore, the cavity length of the micro-resonance area can be controlled by controlling the height of the polished reflective surface. That is, the higher the height of the polished reflective surface, the smaller the thickness of the cavity length adjustment layer (that is, the silicon dioxide layer) above it, and the smaller the cavity length of the corresponding micro-resonance cavity; conversely, the lower the height of the polished reflective surface, the greater the thickness of the cavity length adjustment layer above it, and the greater the cavity length of the corresponding micro-resonance cavity.

[0043] In addition, the three metal reflection areas are polished to form a polished reflection surface. The polishing process is cleverly used to make the light reflection surface flatter and smoother, so that the reflectivity is better, so that the height difference of the metal layer can be more accurately controlled to form different cavity lengths, which improves the brightness of the emitted light, while reducing power consumption and improving the yield. Since the surface of the cavity length adjustment layer covering the three metal reflection areas is on the same horizontal plane, the surface of the cavity length adjustment layer can be directly polished uniformly, thereby further ensuring the smoothness of the micro-resonance cavity and better and more accurately controlling the cavity length.

[0044] The specific details of the process of forming the above three metal reflective areas can be referred to the process of forming the metal reflective areas in the above embodiment, which will not be described in detail here.

[0045] Furthermore, if Figures 5A-5FAs shown, the method for manufacturing the OLED micro-resonant cavity structure also includes the steps of: after the metal reflective region is formed, an electrode connection column 122 is formed in the cavity length adjustment layer above it, and the electrode connection column 122 is connected to the metal reflective region. The formation of the electrode connection column 122 mainly includes the following steps: forming a fourth anti-reflection layer 119 on the third cavity length adjustment layer 118; covering the anti-reflection layer with a fourth mask layer 120, the mask layer can be a photoresist PR, and coating a layer of positive photoresist on it, defining the position and size of the electrode connection column 122 through the mask, and then transferring the pattern on the mask to the photoresist layer PR through exposure to form a mask layer; using the mask layer as a mask, etching the cavity length adjustment layer downward to form three Via holes 121 (i.e., vias, which can be through holes, blind holes or buried holes) corresponding to the three metal reflective regions; removing the mask layer; filling the Via holes 121 with a conductive material to form an electrode connection column 122.

[0046] In order to form a complete OLED light-emitting device, the following steps can be continued: a light-emitting layer 123 is formed above the three metal reflection areas where the electrode connecting pillars 122 are made, and each metal reflection area corresponds to a light-emitting material; a semi-transparent conductive layer 124 is formed above the light-emitting layer 123; an electrode connecting pillar is also formed on the substrate 101 at the bottom of the metal reflection area; a CMOS device 125 is made under the substrate 101, and the electrodes of the CMOS device 125 are connected to the electrode connecting pillars in the substrate 101.

[0047] In one embodiment of the present invention, the semi-transparent conductive layer 124 is a cathode conductive layer, and the metal reflective area is an anode conductive layer. Among them, any suitable process such as ALD, CVD, PVD, electroplating, etc. can be used to cover the light-emitting layer 123 of the micro-resonant cavity structure with a semi-transparent cathode material layer, and further form a semi-transparent cathode conductive layer by photolithography. The anode in the CMOS device 125 is connected to the electrode connection column 122 in the substrate 101.

[0048] By the manufacturing method of the OLED micro-resonant cavity structure of the above embodiment, an OLED micro-resonant cavity structure can be formed, which includes a substrate, an insulating layer, at least one metal reflective area, a cavity length adjustment layer and a light-emitting layer in order from bottom to top, wherein the metal reflective area is formed by groove engraving and metal deposition, and the surface of the metal reflective area is polished to form a polished reflective surface; wherein the OLED micro-resonant cavity is formed between the polished reflective surface, the cavity length adjustment layer and the light-emitting layer. After the original light emitted by the light-emitting layer passes through the cavity length adjustment layer, it forms constructive interference with the reflected light of the polished reflective surface of the corresponding metal reflective area, that is, constructive interference is formed in the formed micro-resonant cavity.

[0049] Furthermore, in order to realize the micro-resonant cavity structure of the full-color OLED, at least three metal reflection areas can be provided, and corresponding R light-emitting layers, G light-emitting layers and B light-emitting layers are also provided above the cavity length adjustment layer, and the polished reflection surfaces of different metal reflection areas have different heights. The formation of different metal reflection areas can refer to the above method embodiment, which is not described in detail here.

[0050] In one embodiment of the present invention, the OLED micro-resonance cavity structure is an anode micro-resonance cavity structure. Specifically, an electrode connection column can be set in the cavity length adjustment layer to communicate with the metal reflection area, and the metal reflection area is then connected to the anode of the circuit through the substrate below.

[0051] like Fig. 5F As shown, the present invention also provides an organic light emitting diode, including the OLED micro-resonance cavity structure described in the above embodiment, and at least one semi-transparent conductive layer 124 is provided thereon, and the metal reflective area of ​​the OLED micro-resonance cavity structure serves as another conductive layer, and the polarities of the two conductive layers are different.

[0052] In summary, through the OLED micro-resonance cavity structure manufacturing method provided by the present invention, a metal reflection area is formed by grooving and depositing metal under the micro-resonance cavity of the organic light-emitting diode OLED, and a polished reflection surface is made by polishing on the surface of the metal reflection area, and a cavity length adjustment layer is covered on the polished reflection surface. After the original light emitted by the light-emitting layer passes through the cavity length adjustment layer, it forms constructive interference with the reflected light of the polished reflection surface. The unexpected effect is that the present invention cleverly uses the Damascus process to form a metal reflection area, and polishing makes the reflection surface flatter and smoother, so that the reflectivity is better, the brightness of the emitted light is improved, the power consumption is reduced, and the yield is improved; and the distance between the polished reflection surface and the light-emitting layer determines the cavity length of the micro-resonance cavity, and by polishing to control the polished reflection surface to be smooth and highly consistent, it is easier to control the precise cavity length of the micro-resonance cavity. When making a full-color organic light-emitting diode OLED, at least three metal reflection areas are formed, and the cavity length of the corresponding micro-resonance cavity is adjusted by controlling the different heights of the polished reflection surfaces of the three metal reflection areas, so that it is easier to accurately realize the constructive interference of light of different colors in the micro-resonance cavity.

[0053] It should be pointed out that, according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, and two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.

[0054] The order of execution of each step in the above embodiment does not mean the order of execution. The order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present application.

[0055] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should fall within the scope of protection of the appended claims of the present invention.

Claims

1. A method for manufacturing an OLED micro-resonance cavity structure, characterized in that: include: providing a substrate; forming an insulating layer on the substrate; A metal reflection area is formed on the insulating layer by grooving and depositing metal, and a surface of the metal reflection area is polished to form a polished reflection surface; forming a cavity length adjustment layer covering the metal reflection area; A light emitting layer corresponding to the metal reflective area is formed above the cavity length adjustment layer. After passing through the cavity length adjustment layer, the original light emitted by the light emitting layer forms constructive interference with the reflected light of the polished reflective surface of the corresponding metal reflective area.

2. The method for manufacturing an OLED micro-resonance cavity structure according to claim 1, characterized in that: The steps for forming the metal reflective area specifically include: forming a pad layer and an anti-reflective layer located above the insulating layer; forming a mask layer covering the anti-reflective layer; etching a groove using the mask layer as a mask and the insulating layer as a reference layer; removing the mask layer; forming a metal reflective layer on the groove; and polishing the metal reflective layer to form a polished reflective surface.

3. The method for manufacturing an OLED micro-resonance cavity structure according to claim 2, characterized in that: In the process of forming the metal reflective area, an isolation layer is first formed on the groove, and then a metal reflective layer is formed on the isolation layer.

4. The method for manufacturing an OLED micro-resonance cavity structure according to claim 1, characterized in that: At least three metal reflection areas are formed on the insulating layer, and the polished reflection surfaces of different metal reflection areas have different heights; and the corresponding first light-emitting layer, second light-emitting layer and third light-emitting layer are formed on the cavity length adjustment layer.

5. The method for manufacturing an OLED micro-resonance cavity structure according to claim 4, characterized in that: The steps for forming the three metal reflection areas specifically include: Forming a first anti-reflection layer on the insulating layer, forming a first mask layer covering the anti-reflection layer; etching a first groove using the first mask layer as a mask and the insulating layer as a reference layer; removing the first mask layer, forming a first metal reflection layer on the first groove, polishing the first metal reflection layer to form a first polished reflection surface, and completing the production of a first metal reflection area; Forming a first cavity length adjustment layer covering the first metal reflection area, forming a second anti-reflection layer located on the first cavity length adjustment layer, and forming a second mask layer covering the second anti-reflection layer; etching a second groove using the second mask layer as a mask and the insulating layer as a reference layer; removing the second mask layer, forming a second metal reflection layer on the second groove, polishing the second metal reflection layer to form a second polished reflection surface, and completing the production of the second metal reflection area; Forming a second cavity length adjustment layer on the second metal reflection area, forming a third anti-reflection layer located on the second cavity length adjustment layer, and forming a third mask layer covering the third anti-reflection layer; etching a third groove using the third mask layer as a mask and the insulating layer as a reference layer; removing the third mask layer, forming a third metal reflection layer on the third groove, polishing the third metal reflection layer to form a third polished reflection surface, and completing the production of the third metal reflection area; Among them, the heights of the three polished reflective surfaces are different.

6. The method for manufacturing an OLED micro-resonance cavity structure according to any one of claims 1 to 5, characterized in that: The method further comprises the following steps: after the metal reflection area is formed, an electrode connection column is formed in the cavity length adjustment layer above the metal reflection area, and the electrode connection column is connected with the metal reflection area.

7. An OLED micro-resonant cavity structure, characterized in that: include: substrate; an insulating layer, located on the substrate; At least one metal reflection area is located on the insulating layer, the metal reflection area is formed by groove engraving and metal deposition, and the surface of the metal reflection area is polished to form a polished reflection surface; A cavity length adjustment layer covering the metal reflection area; The light-emitting layer is located above the cavity length adjustment layer. The original light emitted by the light-emitting layer forms constructive interference with the reflected light of the polished reflective surface of the corresponding metal reflective area after passing through the cavity length adjustment layer.

8. The OLED micro-resonant cavity structure according to claim 7, characterized in that: It comprises at least three metal reflection areas, and corresponding R light-emitting layer, G light-emitting layer and B light-emitting layer are arranged above the cavity length adjustment layer, and the polished reflection surfaces of different metal reflection areas have different heights.

9. The OLED micro-resonant cavity structure according to claim 7, characterized in that: An electrode connection column is arranged in the cavity length adjustment layer and is connected with the metal reflection area.

10. An organic light emitting diode, characterized in that: The OLED micro-resonance cavity structure comprises any one of claims 7 to 9, and at least one semi-transparent conductive layer is arranged thereon, and the metal reflective region of the OLED micro-resonance cavity structure serves as another conductive layer, and the polarities of the two conductive layers are different.

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