OLED Microresonator Structure and Its Fabrication Method

Abstract

The present invention discloses an OLED microresonator structure and a manufacturing method thereof. The method includes the steps of: providing a substrate; forming an insulating layer on the substrate; forming a metal reflection region on the insulating layer by means of grooving and metal deposition, and forming a polished reflection surface on its surface by polishing; forming a cavity length adjustment layer covering the metal reflection region; forming a light-emitting layer corresponding to the metal reflection region 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 reflection surface of the corresponding metal reflection region after passing through the cavity length adjustment layer. The present invention cleverly forms the metal reflection region by means of the damascene process, and makes the reflection surface flatter and smoother through polishing, improves the reflectivity, reduces the power consumption, and improves the yield; moreover, the distance between the polished reflection surface and the light-emitting layer determines the cavity length of the microresonator, and by controlling the polished reflection surface to be smooth and of consistent height through polishing, it is easier to control the precise cavity length of the microresonator.

Description

Technical Field

[0001] The present invention relates to the field of display technologies, and particularly to an OLED microcavity structure and a manufacturing method thereof. Background Art

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

[0003] In the manufacturing process of OLED, a single-layer structure with uniform thickness of BRG (blue light, red light, green light) is generally adopted, but the light color of this structure is not pure 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 structures mainly form cavity lengths with different thicknesses by etching the silicon dioxide layer, but the etched surface is not smooth and cannot be polished. And this process has complex implementation technology, it is difficult to control the microcavity thickness, the amount of loss of the reflective layer metal Al is large, the reflectivity is low, the device brightness 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 microcavity structure and a manufacturing method thereof that can effectively control the cavity length of the OLED microcavity and have a high reflectivity.

[0005] The technical solution adopted by the present invention is as follows:

[0006] Provide a manufacturing method of an OLED microcavity structure, including:

[0007] Provide a substrate;

[0008] Form an insulating layer on the substrate;

[0009] Form a metal reflection region on the insulating layer by means of grooving and metal deposition, and the surface of the metal reflection region is polished to form a polished reflection surface;

[0010] Form a cavity length adjustment layer covering the metal reflection region;

[0011] Form a light-emitting layer corresponding to the metal reflection region 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 reflection surface of the corresponding metal reflection region.

[0012] Continuing with the above technical solution, the steps for forming the metal reflection region specifically include: forming a buffer layer and an anti-reflection layer on the insulating layer; forming a mask layer covering the anti-reflection layer; using the mask layer as a mask and the insulating layer as a reference layer to etch a groove; removing the mask layer; forming a metal reflection layer on the groove; and polishing the metal reflection layer to form a polished reflection surface.

[0013] Continuing with the above technical solution, during the formation of the metal reflection region, a isolation layer is first formed on the groove, and then a metal reflection layer is formed on the isolation layer.

[0014] Continuing with the above technical solution, at least three metal reflection regions are formed on the insulating layer, and the heights of the polished reflection surfaces of different metal reflection regions are different; and corresponding first light-emitting layer, second light-emitting layer, and third light-emitting layer are formed above the cavity length adjustment layer.

[0015] Continuing with the above technical solution, the steps for forming the three metal reflection regions specifically include:

[0016] Forming a first anti-reflection layer on the insulating layer, forming a first mask layer covering the anti-reflection layer; using the first mask layer as a mask and the insulating layer as a reference layer to etch a first groove; removing the first mask layer, forming a first metal reflection layer on the first groove, and polishing the first metal reflection layer to form a first polished reflection surface, completing the fabrication of the first metal reflection region;

[0017] Forming a first cavity length adjustment layer covering the first metal reflection region, forming a second anti-reflection layer on the first cavity length adjustment layer, forming a second mask layer covering the second anti-reflection layer; using the second mask layer as a mask and the insulating layer as a reference layer to etch a second groove; removing the second mask layer, forming a second metal reflection layer on the second groove, and polishing the second metal reflection layer to form a second polished reflection surface, completing the fabrication of the second metal reflection region;

[0018] Forming a second cavity length adjustment layer on the second metal reflection region, forming a third anti-reflection layer on the second cavity length adjustment layer, forming a third mask layer covering the third anti-reflection layer; using the third mask layer as a mask and the insulating layer as a reference layer to etch a third groove; removing the third mask layer, forming a third metal reflection layer on the third groove, and polishing the third metal reflection layer to form a third polished reflection surface, completing the fabrication of the third metal reflection region;

[0019] Among them, the heights of the three polished reflection surfaces are different.

[0020] Continuing with the above technical solution, it further includes the step: after the metal reflection region is formed, an electrode connection post is formed in the cavity length adjustment layer above it, and the electrode connection post is communicated with the metal reflection region.

[0021] The present invention also provides an OLED microresonator structure, comprising:

[0022] a substrate;

[0023] an insulating layer, located above the substrate;

[0024] at least one metal reflection region, located above the insulating layer, which is formed by grooving and depositing metal, and the surface of the metal reflection region is polished to form a polished reflection surface;

[0025] a cavity length adjustment layer, covering the metal reflection region;

[0026] a light-emitting layer, located 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 reflection surface of the corresponding metal reflection region.

[0027] According to the above technical solution, it includes at least three metal reflection regions, and corresponding R light-emitting layer, G light-emitting layer and B light-emitting layer are further provided above the cavity length adjustment layer, and the heights of the polished reflection surfaces of different metal reflection regions are different.

[0028] According to the above technical solution, electrode connection posts are provided in the cavity length adjustment layer and are communicated with the metal reflection regions.

[0029] The present invention also provides an organic light-emitting diode, comprising the OLED microresonator structure described in the above technical solution, and at least one layer of semi-transparent conductive layer is provided thereon, and the metal reflection region of the OLED microresonator structure serves as another conductive layer, and the polarities of the two conductive layers are different.

[0030] The beneficial effects produced by the present invention are as follows: The present invention forms a metal reflection region by grooving and depositing metal below the microresonator of the organic light-emitting diode OLED, and makes a polished reflection surface by polishing on the surface of the metal reflection region, and then covers a cavity length adjustment layer 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. Unexpectedly, the present invention cleverly uses the damascene process to form the metal reflection region, and through polishing, the reflection surface is flatter, smoother and has a higher reflectivity, thereby improving the brightness of the emitted light, reducing the 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 microresonator, and by polishing to control the polished reflection surface to be smooth and of the same height, it is easier to control the precise cavity length of the microresonator.

[0031] Furthermore, when manufacturing a full-color organic light-emitting diode OLED, at least three metal reflection regions are formed, and the cavity lengths of the corresponding microresonators are adjusted by controlling the different heights of the polished reflection surfaces of the three metal reflection regions, so as to achieve constructive interference of different colors of light in the microresonator.

[0032] Furthermore, when fabricating the metal reflection region, the insulating layer is used as a reference layer to etch the grooves, which can better control the depth of the grooves and reduce the process difficulty.

[0033] Furthermore, by forming an anti-reflection coating at the bottom of the metal reflection region, the standing wave effect generated during mask exposure can be effectively prevented from affecting the dissolution effect of the exposed part.

[0034] Furthermore, by forming an isolation layer below the metal reflection region, the metal migration of the metal reflection region into the substrate can be effectively prevented from causing leakage or light non-uniformity.

[0035] Of course, it is not necessary for any product implementing the present invention to simultaneously achieve all the above-mentioned advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for describing the embodiments or the prior art. Obviously, the following-described drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0037] Figure 1 is a flowchart of a method for fabricating an OLED microresonator structure according to an embodiment of the present invention;

[0038] Figures 2A - 2G is a schematic cross-sectional structure diagram during the fabrication process of an OLED microresonator structure according to an embodiment of the present invention;

[0039] Figures 3A - 3G is a schematic cross-sectional structure diagram during the fabrication process of a full-color OLED microresonator structure according to an embodiment of the present invention;

[0040] Figures 4A - 4G is a schematic cross-sectional structure diagram during the fabrication process of a full-color OLED microresonator structure according to an embodiment of the present invention;

[0041] Figures 5A - 5F is a schematic cross-sectional structure diagram during the fabrication process of an organic light-emitting diode (OLED) according to an embodiment of the present invention.

[0042] In the figure: 101, substrate; 102, insulating layer; 103, cushion layer; 104, first anti-reflection layer; 105, first mask layer; 106, first isolation layer; 107, first metal reflection layer; RZ, metal reflection area; 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 connection post; 123, light-emitting layer; 124, semi-transparent conductive layer; 125, CMOS device. Detailed implementation mode

[0043] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to 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.

[0044] It should be noted that the diagrams provided in the embodiments of the present invention only illustrate the basic concept of the present invention in a schematic manner. Therefore, only the components related to the present invention are shown in the diagrams, rather than being drawn according to the number, shape and size of the components in actual implementation. The type, quantity and ratio of each component in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0045] In the present invention, it should also be noted that when terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. appear, the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation to the present application. In addition, when terms such as "first" and "second" appear, they are only used for descriptive and distinguishing purposes and cannot be understood as indicating or implying relative importance.

[0046] In addition, it should also be noted that the features of various embodiments of the present invention can be partially or wholly combined or integrated, and as can be understood by those skilled in the art, they can interact and operate in different ways. Each embodiment can be implemented independently of each other or in an associated relationship.

[0047] This patent ingeniously utilizes the Damascus process to form a metal reflection region, and the surface of the metal reflection region is polished to form a polished reflective surface. This polished reflective surface serves as the bottom reflective surface of the microresonator cavity. It is both flat and smooth, with an extremely high reflectivity, and the distance between it and the light-emitting layer, that is, the cavity length of the microresonator cavity, can be precisely controlled.

[0048] As Figure 1 shown, the manufacturing method of the OLED microresonator cavity structure in this embodiment mainly includes the following steps:

[0049] S1. Provide a substrate;

[0050] S2. Form an insulating layer on the substrate;

[0051] S3. Form a metal reflection region on the insulating layer by grooving and depositing metal, and the surface of the metal reflection region is polished to form a polished reflective surface;

[0052] S4. Form a cavity length adjustment layer covering the metal reflection region;

[0053] S5. Form a light-emitting layer corresponding to the metal reflection region 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 reflection region.

[0054] Among them, a microresonator 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 this microresonator cavity. Since the polished reflective layer formed by polishing in the present invention has a smooth surface, it can ensure that the reflectivity of the reflective surface is highly consistent and the reflection efficiency is high, thereby ensuring the accuracy of the cavity length of the microresonator cavity.

[0055] Please refer to Figure 2A , in step S1, the substrate 101 can be selected as a silicon substrate or a silicon dioxide substrate. In step S2, an insulating layer 102 is formed on the substrate 101. This insulating layer 102 can be silicon nitride SiN, and specifically, plasma-enhanced chemical vapor deposition PECVD deposition process can be used. This insulating layer 102 can be used as a reference layer when forming the metal reflection region later, so as to better control the thickness of the metal reflection region. Silicon oxynitride SiON can also be formed on this insulating layer 102 as a bottom anti-reflection coating BARC, which can prevent the standing wave effect from occurring during the subsequent exposure of the photoresist PR, affecting the dissolution effect of the exposed part of the positive photoresist.

[0056] Please refer to Figures 2A - 2G , the specific steps for forming the metal reflection region include:

[0057] S31. Form a pad layer 103 and a first anti-reflection layer 104 on the insulating layer 102. The material of the anti-reflection layer can be silicon oxynitride SiON, which can be used as a bottom anti-reflection coating BARC to prevent the standing wave effect during the subsequent exposure of the photoresist PR and affect the dissolution effect of the exposed part of the positive photoresist. Among them, the pad layer 103 mainly provides space for etching the groove. The material of the pad layer 103 and the cavity length adjustment layer can be the same or different. In the embodiment of the present invention, the materials of the two are selected to be the same, such as silicon dioxide.

[0058] S32. Cover a first mask layer 105 on the first anti-reflection layer 104. The first mask layer 105 can be a photoresist PR, and a positive photoresist is coated thereon. The position and size of the metal reflection area are defined through a photomask, and then the pattern on the photomask is transferred to the photoresist layer PR through exposure to form the first mask layer 105.

[0059] S33. Using the first mask layer 105 as a mask and the insulating layer 102 as a reference layer, etch the first anti-reflection layer 104, the pad layer 103, and the insulating layer 102 downward, even reaching the substrate 101, to form a first groove with a certain depth. Specifically, dry etching can be used to etch the first groove.

[0060] S34. After the first groove is formed, remove the first mask layer 105.

[0061] S35. Form a first metal reflection layer 107 on the first groove. Specifically, various physical vapor deposition PVD processes can be used to deposit aluminum Al on the groove. In order to prevent the first metal reflection layer 107 from migrating into the silicon substrate and causing leakage or light non-uniformity, a first isolation layer 106 can be formed at the bottom of the first groove first, such as depositing titanium Ti or titanium nitride TiN on the first groove by using various physical vapor deposition PVD processes.

[0062] S36. Polish the first metal reflection layer 107 to form a polished reflection surface, thereby completing the production of a metal reflection area RZ. Specifically, chemical mechanical polishing CMP can be used to remove the excess metal reflection layer, and the thickness of the first metal reflection layer 107 can be controlled according to the position of the insulating layer 102.

[0063] In step S4, a first cavity length adjustment layer 108 covering the metal reflection area is formed. Its main function is to transmit light and is the main body for forming the microresonator. Its material can be silicon dioxide SiO2.

[0064] In step S5, suitable process technologies such as evaporation coating or inkjet printing can be adopted to form an organic light-emitting layer on the first cavity length adjustment layer 108. 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 can be changed into various shapes commonly known to those skilled in the art.

[0065] In a preferred embodiment of the present invention, at least three metal reflection regions can be formed. The heights of the polished reflection surfaces of different metal reflection regions are different, and corresponding first light-emitting layer, second light-emitting layer, and third light-emitting layer are formed above the cavity length adjustment layer. The light-emitting colors of the three light-emitting layers are different, and can be red R, green G, and blue B. The order of the three colors can be set according to needs.

[0066] Such as Figures 2A - 2G , Figures 3A - 3G , Figures 4A - 4G FIGS. are process diagrams for the formation of three metal reflection regions. In this embodiment, the three metal reflection regions RZ respectively correspond to the light-emitting regions of red R, green G, and blue B. The formation process of the three metal reflection regions specifically includes the following steps:

[0067] The production of the first metal reflection region can refer to Figures 2A - 2G , form a pad layer 103 and a first anti-reflection layer 104 on the insulating layer 102, and form 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, etch the first groove; remove the first mask layer 105, form a first metal reflection layer 107 on the first groove, and polish the first metal reflection layer 107 to form a first polished reflection surface, thereby completing the production of the first metal reflection region. In order to prevent the metal reflection layer from migrating into the substrate 101 to cause leakage or light non-uniformity, a first isolation layer 106 can be formed at the bottom of the first groove first.

[0068] The production of the second metal reflection region can refer to Figures 3A - 3G , form a first cavity length adjustment layer 108 covering the first metal reflection region. The material of the first cavity length adjustment layer 108 can be selected as silicon dioxide; form a second anti-reflection layer 109 on the first cavity length adjustment layer 108, and form 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, etch the second groove; remove the second mask layer 110, form a second metal reflection layer 112 on the second groove, and polish the second metal reflection layer 112 to form a second polished reflection surface, completing the production of the second metal reflection region. In order to prevent the metal reflection layer from migrating into the first cavity length adjustment layer 108 to cause leakage or light non-uniformity, a second isolation layer 111 can be formed at the bottom of the second groove first.

[0069] The fabrication of the third metal reflection region can refer to Figures 4A - 4G , forming a second cavity length adjustment layer 113 on the second metal reflection region. The material of the second cavity length adjustment layer 113 can be selected as silicon dioxide, which is the same as the material of the first cavity length adjustment layer 108 of the second metal reflection region; forming a third anti-reflection layer 114 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 a 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 to form a third polished reflection surface, and completing the fabrication of the third metal reflection region. In order to prevent the metal reflection layer from migrating into the second cavity length adjustment layer 113 to cause leakage or light non-uniformity, a third isolation layer 116 can be formed at the bottom of the third groove first.

[0070] In order to form a microresonator corresponding to the third metal reflection region, finally, a third cavity length adjustment layer 118 needs to be formed above the third metal reflection region.

[0071] Among them, the heights of the polished reflection surfaces of the three metal reflection regions are different, and this is used to control the cavity length of the microresonator.

[0072] Specifically, in the prior art, if multiple-color microresonators are to be formed, mainly by directly depositing a light-transmitting layer on the reflective layer metal, and then etching to form light-transmitting layers with different thicknesses (the thickness of the light-transmitting layer determines the cavity length of the microresonator). Because the thicknesses of the light-transmitting layers are different, the top surface cannot be polished, resulting in an uneven cavity, inconsistent reflection heights, and a low reflectivity, thus unable to ensure a smooth cavity and an accurate cavity length. However, the original light emitted by the light-emitting layer of this patent, after passing through the cavity length adjustment layer, forms constructive interference with the reflected light of the polished reflection surface. Since the wavelengths of red, green, and blue light are different, and the cavity length of the microresonator corresponds to the desired light wavelength. And the microresonant distance between the polished reflection surface and the light-emitting layer determines the cavity length of the microresonator. The formation of the three metal reflection regions in this embodiment is based on the insulating layer as a reference layer. Therefore, the bottoms of the three metal reflection regions are on the same horizontal plane. When the last metal reflection region is completed, the surface of the cavity length adjustment layer covering the three metal reflection regions is also on the same horizontal plane (no need to etch to form different thicknesses, but can be polished uniformly to be smoother). Therefore, by controlling the height of the polished reflection surface, the cavity length of the microresonant region can be controlled, that is, the higher the height of the polished reflection surface, the smaller the thickness of the cavity length adjustment layer (i.e., the silicon dioxide layer) above it, and the smaller the corresponding cavity length of the microresonator; conversely, the lower the height of the polished reflection surface, the larger the thickness of the cavity length adjustment layer above it, and the larger the corresponding cavity length of the microresonator.

[0073] In addition, the three metal reflection regions are all formed with polished reflection surfaces through polishing. By skillfully leveraging the polishing process, the reflection surfaces of light are made flatter and smoother, resulting in better reflectivity. Thus, the height difference of the metal layer can be more precisely controlled to form different cavity lengths, improving the brightness of the emitted light, reducing power consumption, and increasing the yield. Since the surfaces of the cavity length adjustment layers covering the three metal reflection regions are at the same horizontal plane, the surfaces of the cavity length adjustment layers can be directly polished uniformly, further ensuring the smoothness of the microresonator cavity and enabling better and more precise control of the cavity length.

[0074] For the specific details of the formation process of the above three metal reflection regions, reference can be made to the formation process of the metal reflection regions in the above embodiments, which will not be elaborated here one by one.

[0075] Furthermore, as Figures 5A - 5F shown, the manufacturing method of the OLED microresonator cavity structure further includes the steps: after the metal reflection regions are formed, electrode connection posts 122 are formed in the cavity length adjustment layer above them, and the electrode connection posts 122 communicate with the metal reflection regions. The formation of the electrode connection posts 122 mainly includes the following steps: a fourth anti-reflection layer 119 is formed on the third cavity length adjustment layer 118; a fourth mask layer 120 is covered on the anti-reflection layer, and the mask layer can be a photoresist PR, and a positive photoresist is coated on it. The position and size of the electrode connection posts 122 are defined through a photomask, and then the pattern on the photomask is transferred to the photoresist layer PR through exposure to form the mask layer; using the mask layer as a mask, the cavity length adjustment layer is etched 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 reflection regions; the mask layer is removed; a conductive material is filled in the Via holes 121 to form the electrode connection posts 122.

[0076] 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 regions where the electrode connection posts 122 are made, and each metal reflection region corresponds to a kind of light-emitting material; a semi-transparent conductive layer 124 is formed above the light-emitting layer 123; electrode connection posts are also formed at the bottom of the metal reflection regions on the substrate 101; a CMOS device 125 is fabricated below the substrate 101, and the electrodes of the CMOS device 125 are connected to the electrode connection posts in the substrate 101.

[0077] In an embodiment of the present invention, the semi-transparent conductive layer 124 is a cathode conductive layer, and the metal reflection region is an anode conductive layer. Among them, any suitable process such as ALD, CVD, PVD, electroplating, etc. can be used to cover a semi-transparent cathode material layer above the light-emitting layer 123 of the microresonator cavity structure, and further form a semi-transparent cathode conductive layer through lithography. The anode in the CMOS device 125 is connected to the electrode connection posts 122 in the substrate 101.

[0078] Through the manufacturing method of the OLED microresonator structure of the above embodiments, an OLED microresonator structure can be formed, which sequentially includes a substrate, an insulating layer, at least one metal reflection region, a cavity length adjustment layer, and a light-emitting layer from bottom to top. The metal reflection region is formed by grooving and depositing metal, and the surface of the metal reflection region is polished to form a polished reflection surface. A microresonator of the OLED is formed between the polished reflection 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 reflection surface of the corresponding metal reflection region, that is, constructive interference is formed in the formed microresonator.

[0079] Furthermore, in order to realize the microresonator structure of a full-color OLED, at least three metal reflection regions can be provided, and corresponding R light-emitting layer, G light-emitting layer, and B light-emitting layer are also provided above the cavity length adjustment layer, and the heights of the polished reflection surfaces of different metal reflection regions are different. The formation of different metal reflection regions can refer to the method embodiments above and will not be elaborated here.

[0080] In an embodiment of the present invention, the OLED microresonator structure is an anode microresonator structure. Specifically, electrode connection posts can be arranged in the cavity length adjustment layer to communicate with the metal reflection region, and the metal reflection region is then connected to the anode of the circuit through the substrate below.

[0081] As Figure 5F shown, the present invention also provides an organic light-emitting diode, which includes the OLED microresonator structure described in the above embodiments, and at least one layer of semi-transparent conductive layer 124 is provided thereon, and the metal reflection region of the OLED microresonator structure serves as another conductive layer, and the polarities of the two conductive layers are different.

[0082] In summary, through the manufacturing method of the OLED microresonator structure provided by the present invention, a metal reflection region is formed by grooving and depositing metal below the microresonator of the organic light-emitting diode OLED, and a polished reflection surface is fabricated on the surface of the metal reflection region by polishing. A cavity length adjustment layer is also 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 ingeniously utilizes the damascene process to form the metal reflection region, and through polishing, the reflection surface is made flatter and smoother, thereby making the reflectivity better, improving the brightness of the emitted light, reducing the power consumption, and improving the yield. Moreover, the distance between the polished reflection surface and the light-emitting layer determines the cavity length of the microresonator, and by polishing to control the polished reflection surface to be smooth and of consistent height, it is easier to control the precise cavity length of the microresonator. When manufacturing a full-color organic light-emitting diode OLED, at least three metal reflection regions are formed, and the cavity lengths of the corresponding microresonators are adjusted by controlling the different heights of the polished reflection surfaces of the three metal reflection regions, so as to more easily and precisely realize the constructive interference of different colors of light in the microresonator.

[0083] It should be noted that, according to the needs of implementation, each step / component described in this application can be split into more steps / components, or 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.

[0084] In the above embodiments, the magnitudes of the sequence numbers of the steps do not mean the order of execution. The execution order of each process should be determined according to its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of this application.

[0085] It should be understood that those of ordinary skill in the art can make improvements or transformations according to the above description, and all such improvements and transformations should fall within the protection scope of the appended claims of the present invention.

Claims

1. A manufacturing method of an OLED micro-resonator structure, characterized in that Comprising: Providing a substrate; Forming an insulating layer on the substrate; Forming a metal reflection region on the insulating layer by grooving and depositing metal, and forming a polished reflection surface by polishing the surface of the metal reflection region; taking the insulating layer as a reference layer, forming at least three metal reflection regions on the insulating layer, and the heights of the polished reflection surfaces of different metal reflection regions are different; and forming corresponding first, second, and third light-emitting layers above the cavity length adjustment layer; Forming a cavity length adjustment layer covering the metal reflection region; Forming a light-emitting layer corresponding to the metal reflection region 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 reflection surface of the corresponding metal reflection region; Wherein, the distance between the polished reflection surface and the light-emitting layer determines the cavity length of the microresonator, and the precise cavity length of the microresonator is controlled by polishing to make the polished reflection surface smooth and of consistent height.

2. The manufacturing method of the OLED micro-resonator structure according to claim 1, characterized in that, The forming step of the metal reflection region specifically includes: forming a pad layer and an antireflection layer on the insulating layer; forming a mask layer covering the antireflection layer; using the mask layer as a mask and the insulating layer as a reference layer to etch a groove; removing the mask layer; forming a metal reflection layer on the groove; polishing the metal reflection layer to form a polished reflection surface.

3. The manufacturing method of the OLED micro-resonator structure according to claim 2, wherein During the formation of the metal reflection region, first form an isolation layer on the groove, and then form a metal reflection layer on the isolation layer.

4. The manufacturing method of the OLED micro-resonator structure according to claim 1, characterized in that, The forming steps of the three metal reflection regions specifically include: Forming a first antireflection layer on the insulating layer, and forming a first mask layer covering the antireflection layer; using the first mask layer as a mask and the insulating layer as a reference layer to etch a first groove; removing the first mask layer, forming a first metal reflection layer on the first groove, and polishing the first metal reflection layer to form a first polished reflection surface, completing the fabrication of the first metal reflection region; Forming a first cavity length adjustment layer covering the first metal reflection region, forming a second antireflection layer on the first cavity length adjustment layer, and forming a second mask layer covering the second antireflection layer; using the second mask layer as a mask and the insulating layer as a reference layer to etch a second groove; removing the second mask layer, forming a second metal reflection layer on the second groove, and polishing the second metal reflection layer to form a second polished reflection surface, completing the fabrication of the second metal reflection region; Forming a second cavity length adjustment layer on the second metal reflection region, forming a third antireflection layer on the second cavity length adjustment layer, and forming a third mask layer covering the third antireflection layer; using the third mask layer as a mask and the insulating layer as a reference layer to etch a third groove; removing the third mask layer, forming a third metal reflection layer on the third groove, and polishing the third metal reflection layer to form a third polished reflection surface, completing the fabrication of the third metal reflection region; Wherein, the heights of the three polished reflection surfaces are different.

5. The manufacturing method of the OLED microresonator structure according to any one of claims 1-4, characterized in that, It further includes the step: after the metal reflection region is formed, forming an electrode connection column in the cavity length adjustment layer above it, and the electrode connection column is communicated with the metal reflection region.

6. An OLED microcavity structure, characterized in that, Comprising: A substrate; An insulating layer, located on the substrate; At least one metal reflection region, located above the insulating layer, the metal reflection region is formed by grooving and depositing metal, and the surface of the metal reflection region is polished to form a polished reflection surface; specifically, with the insulating layer as the reference layer, at least three metal reflection regions are formed above the insulating layer, and the heights of the polished reflection surfaces of different metal reflection regions are different; The cavity length adjustment layer covers the metal reflection region; The light-emitting layer is located 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 reflection surface of the corresponding metal reflection region; Among them, the distance between the polished reflection surface and the light-emitting layer determines the cavity length of the microresonator. By polishing to control the polished reflection surface to be smooth and have a consistent height, the precise cavity length of the microresonator is controlled.

7. The OLED micro-resonator structure according to claim 6, wherein, It includes at least three metal reflection regions, and corresponding R light-emitting layer, G light-emitting layer and B light-emitting layer are also provided above the cavity length adjustment layer, and the heights of the polished reflection surfaces of different metal reflection regions are different.

8. The OLED micro-resonator structure according to claim 6, characterized in that, Electrode connection posts are provided in the cavity length adjustment layer and are connected to the metal reflection region.

9. An organic light emitting diode, characterized in that, It includes the OLED microresonator structure described in claim 7 or 8, and at least one layer of semi-transparent conductive layer is provided thereon, and the metal reflection region of the OLED microresonator structure serves as another conductive layer, and the polarities of the two conductive layers are different.

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