Preparation method of silicon-based OLED micro-display anode structure and silicon-based OLED micro-display anode structure

Abstract

The invention discloses a preparation method of a silicon-based OLED micro-display anode structure. The preparation method comprises the following steps: S1, providing a driving circuit substrate; s2, forming a first composite film layer on one side of the driving circuit substrate, wherein the first composite film layer comprises a SiO film layer and a SiN film layer; s3, a metal film layer is formed on the side, away from the driving circuit substrate, of the first composite film layer, and then an anode film layer is formed; s4, filling openings in an anode pixel region in one side, far away from the driving circuit substrate, of the anode film layer, and then forming a transparent inorganic film layer; s5, preparing a conduction connection structure on one side, far away from the driving circuit substrate, of the transparent inorganic film layer; s6, preparing an ITO layer on one side, far away from the driving circuit substrate, of the conduction connection structure, wherein the ITO layer covers the transparent inorganic film layer; and S7, etching the ITO layer, the transparent inorganic film layer, the anode film layer, the SiO film layer and the SiN film layer, and forming a slope angle at the SiN film layer. According to the preparation method of the anode structure of the silicon-based OLED micro-display, the novel anode reflecting layer is manufactured, so that the process steps and material consumption can be reduced, the cost is reduced, the problem of optical crosstalk is effectively solved, and the color gamut and the brightness of a product are improved. The invention further discloses an anode structure of the silicon-based OLED micro display.

Description

Technical Field

[0001] The present invention belongs to the technical field of silicon-based OLED, and in particular, relates to a method for preparing an anode structure of a silicon-based OLED micro-display and an anode structure of a silicon-based OLED micro-display. Background Art

[0002] Silicon-based OLED display technology has the characteristics of self-luminescence, high contrast, and high response speed, and is widely used in virtual reality (VR), augmented reality (AR) and other devices. In the existing silicon-based OLED, a silicon substrate with a CMOS circuit is used as the substrate, and an anode reflection layer, an OLED evaporation layer, a packaging layer, a CF (Color Filter) color resistance layer and a packaging cover layer are stacked on top.

[0003] One of the existing methods for preparing the anode reflective layer is to connect a Cu film layer to a CMOS substrate, and then plate an Al film layer as the anode reflective layer. Then, chemical mechanical polishing is used to remove the excess part to make it flat, and then a strong microcavity layer and other OLED layers (such as Figure 8 ), the production process needs to be equipped with complete chemical mechanical polishing process equipment, and the corresponding cost will also increase.

[0004] The second existing method for preparing the anode reflective layer is to use Ti / Al / TiN to connect with the CMOS substrate, and then prepare an ITO layer as a microcavity adjustment layer (such as Fig. 9 ). This method cannot limit the direction of the emitted light. Oblique emitted light is prone to light crosstalk between adjacent pixels, reducing the color gamut and display brightness.

[0005] It is hoped to provide an improved method for preparing the anode structure of a silicon-based OLED microdisplay, particularly with regard to how to reduce process steps and material consumption, reduce costs, effectively improve the optical crosstalk problem, and improve product color gamut and brightness. Summary of the invention

[0006] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a method for preparing an anode structure of a silicon-based OLED microdisplay, the purpose of which is to reduce process steps and material consumption and reduce costs.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is: a method for preparing an anode structure of a silicon-based OLED microdisplay, comprising the steps of:

[0008] S1. providing a driving circuit substrate;

[0009] S2, forming a first composite film layer on one side of the driving circuit substrate, the first composite film layer comprising a SiO film layer and a SiN film layer;

[0010] S3, forming a metal film layer on a side of the first composite film layer away from the driving circuit substrate, and then forming an anode film layer;

[0011] S4, filling the openings in the anode pixel region on the side of the anode film layer away from the drive circuit substrate, and then forming a transparent inorganic film layer;

[0012] S5, preparing a conductive connection structure on a side of the transparent inorganic film layer away from the driving circuit substrate;

[0013] S6, preparing an ITO layer on a side of the conductive connection structure away from the driving circuit substrate, wherein the ITO layer covers the transparent inorganic film layer;

[0014] S7, etching the ITO layer, the transparent inorganic film layer, the anode film layer, the SiO film layer and the SiN film layer, and forming a slope angle at the SiN film layer.

[0015] In the step S2, the SiO film layer and the SiN film layer are prepared on the driving circuit substrate by a CVD process, and then etched by a photolithography process.

[0016] In the step S3, the metal film layer is prepared by a PVD process, and then a pattern is formed on the metal film layer by a photolithography process to form an independent anode film layer, and the pattern is used to isolate adjacent anode pixel regions.

[0017] In the step S3, the metal film layer is a composite film layer formed of Ti / AL / TiN.

[0018] In the metal film layer, the thickness of the Al film layer is greater than 400 Å.

[0019] In the step S4, the transparent inorganic film layer is a SiO film layer.

[0020] In the step S5, the conductive connection structure is prepared by a PVD process and a photolithography process, and the conductive connection structure passes through the transparent inorganic film layer and contacts with the first composite film layer.

[0021] The conductive connection structure is a composite film layer formed by Ti / TiN.

[0022] In the step S6, the ITO layer is prepared by PVD process and photolithography process.

[0023] The present invention also provides a silicon-based OLED micro-display anode structure, which is formed by the above method.

[0024] The method for preparing the anode structure of the silicon-based OLED microdisplay of the present invention can manufacture a novel anode reflective layer, reduce process steps and material consumption, reduce costs, effectively improve the light crosstalk problem, and improve the product color gamut and brightness. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] This specification includes the following drawings, which show the following contents:

[0026] Figures 1 to 7 It is a schematic diagram of the preparation process of the anode structure of the silicon-based OLED microdisplay of the present invention;

[0027] Figure 8 is a schematic diagram of the structure of the anode structure prepared by CMP+photolithography;

[0028] Fig. 9 is a schematic structural diagram of an anode structure prepared by photolithography;

[0029] The markings in the figure are:

[0030] 1. Driving circuit substrate; 2. First composite film layer; 3. Metal film layer; 4. Anode film layer; 5. Transparent inorganic film layer; 6. Conductive connection structure; 7. ITO layer; 8. SiO film layer; 9. SiN film layer; 10. First inclined plane; 11. Second inclined plane. DETAILED DESCRIPTION

[0031] The specific implementation methods of the present invention are further explained in detail below by describing the embodiments with reference to the accompanying drawings, with the aim of helping those skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solution of the present invention and facilitating its implementation.

[0032] It should be noted that, in the following embodiments, the “first” and “second” mentioned do not represent an absolute distinction in structure and / or function, nor do they represent a sequential order of execution, but are merely for the convenience of description.

[0033] like Figures 1 to 7 As shown, the present invention provides a method for preparing an anode structure of a silicon-based OLED microdisplay, comprising the following steps:

[0034] S1. providing a driving circuit substrate;

[0035] S2, forming a first composite film layer on one side of the driving circuit substrate, the first composite film layer comprising a SiO film layer and a SiN film layer;

[0036] S3, forming a metal film layer on a side of the first composite film layer away from the driving circuit substrate, and then forming an anode film layer;

[0037] S4, filling the openings in the anode pixel region on the side of the anode film layer away from the drive circuit substrate, and then forming a transparent inorganic film layer;

[0038] S5, preparing a conductive connection structure on a side of the transparent inorganic film layer away from the driving circuit substrate;

[0039] S6, preparing an ITO layer on a side of the conductive connection structure away from the driving circuit substrate, wherein the ITO layer covers the transparent inorganic film layer;

[0040] S7, etching the ITO layer, the transparent inorganic film layer, the anode film layer, the SiO film layer and the SiN film layer, and forming a slope angle at the SiN film layer.

[0041] Specifically, if Figure 1 As shown, in the above step S1, the driving circuit substrate includes a CMOS substrate and a tungsten plug, the bottom layer is a logic driving circuit, and the orange in the figure indicates a tungsten plug. The tungsten plug arranged on the CMOS substrate is used to connect the anode reflective layer manufactured in subsequent processes.

[0042] like Figure 2 As shown, in the above step S2, a SiO film layer and a SiN film layer are prepared on the driving circuit substrate by a CVD process, and then etched by a photolithography process to etch out a desired pattern. Figure 2 The figure shows a schematic diagram of the device structure after the first masking. An anode sub-pixel groove is produced on the first composite film layer by etching, and there are multiple anode sub-pixel grooves.

[0043] like Figure 3 As shown, in the above step S3, a metal film layer is prepared by a PVD process, and the metal film layer is deposited on the first composite film layer and the pattern formed in step S2, and the metal film layer covers the inner wall surfaces of all the anode sub-pixel grooves. Then, a pattern is formed on the metal film layer by a photolithography process to form an independent anode film layer, and the anode film layer is located in the anode sub-pixel groove, and the anode film layer covers the inner wall surfaces of the anode sub-pixel groove, and the pattern is used to isolate adjacent anode sub-pixel grooves.

[0044] In the above step S3, the metal film layer is a composite film layer formed by Ti / Al / TiN. In the metal film layer, the Al film layer is located between the Ti film layer and the TiN film layer. The Ti film layer serves as the bottom layer, and Ti has good adhesion and can form stable chemical bonds with a variety of materials, thereby enhancing the bonding force between the film layer and the substrate. The Al film layer needs to have a certain thickness, and the thickness of the Al film layer is more than 400A, and it has reflective ability. The Al film layer has good conductivity and reflectivity. The TiN film layer serves as the top layer, and TiN not only has excellent wear resistance and corrosion resistance, but also can prevent the Al film layer from reacting with oxygen or water vapor in the air, thereby protecting the performance of the Al film layer.

[0045] In the above step S3, the formed Al film layer is connected to the CMOS substrate, and the Al film layer also serves as an anode reflective layer. The Al film layer between two adjacent anode sub-pixel grooves is removed by photolithography to form a pattern.

[0046] like Figure 3 As shown, in the above step S3, after the metal film layer is manufactured, it is further formed into a desired pattern through a photolithography process to form an independent anode film layer. The formed pattern is used to isolate adjacent anode pixel areas. The anode film layer is located in the anode pixel area.

[0047] like Figure 4 As shown, in the above step S4, a transparent inorganic film layer is prepared by a PVD process and a photolithography process, the transparent inorganic film layer fills the openings in the anode pixel area, and the transparent inorganic film layer covers the anode film layer. Figure 4 Shown is a schematic diagram of the microcavity adjustment layer structure (including through holes) prepared by one or three photolithography processes.

[0048] In the above step S4, the transparent inorganic film layer is a SiO film layer.

[0049] Furthermore, in the above step S4, a transparent inorganic film layer with different thicknesses can be formed by multiple CVD+photolithography. The thickness of the transparent inorganic film layer can be fine-tuned according to the different wavelengths of each sub-pixel to form a microcavity effect to increase the output light intensity.

[0050] like Figure 5 As shown, in the above step S5, the conductive connection structure is prepared by a PVD process and a photolithography process, and the conductive connection structure passes through the transparent inorganic film layer and contacts with the first composite film layer.

[0051] The transparent inorganic film layer is not conductive, so after step S4 is completed, a conductive connection structure needs to be prepared by PVD+photolithography process at the holes pre-prepared on the transparent inorganic film layer. The conductive connection structure is embedded in the holes formed on the transparent inorganic film layer and contacts the first composite film layer below.

[0052] Preferably, the conductive connection structure is a composite film layer formed of Ti / TiN.

[0053] In the above step S6, an ITO layer is prepared by a PVD process and a photolithography process, and the ITO layer covers the conductive connection structure and the transparent inorganic film layer.

[0054] In the above step S7, when preparing Fig. 9 When etching the bottom layer structure, suitable etching conditions can be selected to etch the bottom SiN film layer at a slower speed, forming a certain slope angle, further shrinking the light emission direction.

[0055] like Figure 7As shown, at the positions corresponding to the grooves of each anode sub-pixel, the ITO layer, the transparent inorganic film layer, the anode film layer, the SiO film layer and the SiN film layer are etched. The surface of the SiN film layer finally formed includes a first inclined surface and a second inclined surface, the first inclined surface and the second inclined surface are respectively located on opposite sides of the SiN film layer, the first inclined surface and the second inclined surface are inclined, the first inclined surface and the second inclined surface are distributed in a V shape, the inclined direction of the first inclined surface and the inclined direction of the second inclined surface have an angle and the angle is an acute angle, the angle between the inclined direction of the first inclined surface and the length direction of the CMOS substrate is an acute angle, the angle between the inclined direction of the first inclined surface and the length direction of the CMOS substrate is the same as the angle between the inclined direction of the second inclined surface and the length direction of the CMOS substrate.

[0056] The present invention also provides a silicon-based OLED micro-display anode structure, which is formed by the above method.

[0057] The method for preparing the anode structure of a silicon-based OLED micro-display and the anode structure of a silicon-based OLED micro-display provided by the present invention manufacture a novel anode reflective layer through a photolithography process, thereby solving the problem of relatively complicated processes in the existing anode reflective layer manufacturing process, reducing process steps and material consumption, and reducing costs. At the same time, because the aluminum film layer is in a groove shape, the opaque side wall can limit the light emission direction, which can effectively improve the light crosstalk problem, improve the product color gamut and brightness, and enhance the display effect.

[0058] The present invention is described above by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-mentioned methods. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention; or the above concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A method for preparing a silicon-based OLED microdisplay anode structure, characterized in that: Includes steps: S1. providing a driving circuit substrate; S2, forming a first composite film layer on one side of the driving circuit substrate, the first composite film layer comprising a SiO film layer and a SiN film layer; S3, forming a metal film layer on a side of the first composite film layer away from the driving circuit substrate, and then forming an anode film layer; S4, filling the openings in the anode pixel region on the side of the anode film layer away from the drive circuit substrate, and then forming a transparent inorganic film layer; S5, preparing a conductive connection structure on a side of the transparent inorganic film layer away from the driving circuit substrate; S6, preparing an ITO layer on a side of the conductive connection structure away from the driving circuit substrate, wherein the ITO layer covers the transparent inorganic film layer; S7, etching the ITO layer, the transparent inorganic film layer, the anode film layer, the SiO film layer and the SiN film layer, and forming a slope angle at the SiN film layer.

2. The method for preparing the anode structure of a silicon-based OLED microdisplay according to claim 1, characterized in that: In the step S2, the SiO film layer and the SiN film layer are prepared on the driving circuit substrate by a CVD process, and then etched by a photolithography process.

3. The method for preparing the anode structure of a silicon-based OLED microdisplay according to claim 1, characterized in that: In the step S3, the metal film layer is prepared by a PVD process, and then a pattern is formed on the metal film layer by a photolithography process to form an independent anode film layer, wherein the pattern is used to isolate adjacent anode pixel regions.

4. The method for preparing the anode structure of a silicon-based OLED microdisplay according to any one of claims 1 to 3, characterized in that: In the step S3, the metal film layer is a composite film layer formed of Ti / AL / TiN.

5. The method for preparing the anode structure of a silicon-based OLED microdisplay according to claim 4, characterized in that: In the metal film layer, the thickness of the Al film layer is greater than 400 Å.

6. The method for preparing the anode structure of a silicon-based OLED microdisplay according to any one of claims 1 to 5, characterized in that: In the step S4, the transparent inorganic film layer is a SiO film layer.

7. The method for preparing the anode structure of a silicon-based OLED microdisplay according to any one of claims 1 to 6, characterized in that: In the step S5, the conductive connection structure is prepared by a PVD process and a photolithography process, and the conductive connection structure passes through the transparent inorganic film layer and contacts with the first composite film layer.

8. The method for preparing the anode structure of a silicon-based OLED microdisplay according to claim 6, characterized in that: The conductive connection structure is a composite film layer formed by Ti / TiN.

9. The method for preparing the anode structure of a silicon-based OLED microdisplay according to any one of claims 1 to 8, characterized in that: In the step S6, the ITO layer is prepared by PVD process and photolithography process.

10. A silicon-based OLED microdisplay anode structure, characterized in that: The method is formed by any one of claims 1 to 9.

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