Under-cut structure in silicon-based oleds
Patent Information
- Application Number
- CN202522181274.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-15
- Publication Date
- 2026-11-03
- Estimated Expiration
- 2035-10-15
AI Technical Summary
Micro OLED displays are prone to crosstalk due to the small size of the pixels, which can affect the display quality.
An under-cut structure for silicon-based OLEDs is designed by forming multiple microcavities by setting SIO and SIN layers on a CMOS substrate and setting vias between the microcavities. The under-cut structure is formed by utilizing the etching selectivity of SIN and SIO to ensure that the anode layer is completely disconnected and is separated into multiple sub-units during subsequent deposition of EL and CGL films.
It effectively reduces current crosstalk, improves the display effect of Micro OLED displays, and ensures independent power supply between each anode.
Smart Images
Figure CN224936023U_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the technical field, and particularly relates to an under-cut structure in a silicon-based OLED. Background Technology
[0002] Compared to traditional displays, Micro OLED uses a single-crystal silicon chip as the driving backplane, on which OLED display devices are fabricated, eliminating the need for an external DDIC and effectively increasing the display area of the microdisplay. As a rising star in the display industry, Micro OLED boasts advantages such as light weight, small size, and high resolution, and is widely used in augmented reality (AR) and virtual reality (VR) fields.
[0003] Because Micro OLED displays have small display areas and require high resolution, the pixel size is too small, and current crosstalk can easily occur between the light-emitting units, which seriously affects the display effect of the product. Based on this, this utility model designs an under-cut structure in silicon-based OLEDs. Utility Model Content
[0004] The purpose of this invention is to solve the problems in the prior art and to propose an under-cut structure for silicon-based OLEDs.
[0005] An under-cut structure in a silicon-based OLED is arranged along the vertically upward direction as follows: CMOS substrate layer; SIO layer; SIN layer; Anode layer; ITO film layer; EL layer; CGL film layer; The SIN layer is provided with multiple microcavities at equal intervals, and a via is provided between every two adjacent microcavities, passing through the SIO layer and the SIN layer. The via extends from the CMOS substrate layer to the anode layer.
[0006] In the above structure, an opening with a size smaller than the width of the microcavity is provided above the microcavity. The opening simultaneously separates the anode layer, ITO film layer, EL layer and CGL film layer and forms multiple independent sub-units.
[0007] In the above structure, the morphology of the microcavity includes a square structure.
[0008] In the above structure, the two sides of the microcavity extend laterally below the anode layer.
[0009] In the above structure, the microcavity is formed by adjusting the SIN and SIO etching selectivity ratio to allow the SIN layer to be etched laterally.
[0010] In the above structure, the sub-unit is configured as a trapezoidal structure that is narrow at the top and wide at the bottom.
[0011] In the above structure, the shape of the through hole is set to be wider at the top and narrower at the bottom.
[0012] The beneficial effects of this invention are as follows: By optimizing the dielectric layer structure between vias, this invention optimizes the single SIO layer in the prior art into a superposition of SIO and SIN layers. This allows the SIN to be etched through during anode patterning etching and stop at the SIO to ensure that all anodes are completely disconnected. Furthermore, by adjusting the etching selectivity ratio of SIN and SIO, SIN can form a microcavity and create an undercut. In this way, during subsequent evaporation deposition of EL and CGL, the CGL and EL layers will be separated into multiple sub-units, and continuous distribution of CGL will be avoided, reducing current crosstalk. Attached Figure Description
[0013] Figure 1 This is a schematic diagram of the under-cut structure in a silicon-based OLED disclosed in this utility model.
[0014] Figure 2 This is a schematic diagram of the ITO film deposition structure in the under-cut structure of a silicon-based OLED disclosed in this utility model.
[0015] In the figure: 1 CMOS substrate layer, 2 SiO layer, 3 SiN layer, 31 microcavity, 32 via, 33 opening, 4 anode layer, 5 ITO film layer, 6 EL layer, 7 CGL film layer, 8 remaining part. Detailed Implementation
[0016] To facilitate understanding of this application and to make the aforementioned objectives, features, and advantages of this application more apparent, a detailed description of specific embodiments of this application is provided below in conjunction with the accompanying drawings. Numerous specific details are set forth in the following description to provide a thorough understanding of this application, and preferred embodiments are shown in the accompanying drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application. This application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application; therefore, this application is not limited to the specific embodiments disclosed below. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified. In the description of this application, "several" means at least one, such as one, two, etc., unless otherwise explicitly specified. It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementations. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is only for describing particular implementations and is not intended to limit the scope of this application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0017] Reference Figure 1-2 An under-cut structure in a silicon-based OLED includes a CMOS substrate layer 1, a SiO layer 2, a SiN layer 3, an anode layer 4, an ITO film layer 5, an EL layer 6, and a CGL film layer 7, which are respectively arranged along the vertical upward direction. The SiO layer 2 and the SiN layer 3 are formed on the CMOS substrate by CVD evaporation. The advantage of setting the SiO layer 2 and the SiN layer 3 is that when the anode layer 4 is patterned and etched, it can be controlled to penetrate the SiN layer 3 and stop at the SiO layer 2, thus ensuring that each anode is completely disconnected. Furthermore, multiple microcavities 31 can be simultaneously formed at the location where the SIN layer 3 is etched. The microcavities 31 are formed by lateral etching. By controlling the SIN / SIO etching selectivity ratio, etching can be performed along the bottom of the anode layer 4 towards both sides of the opening 33 at the opening 33 of the SIN layer 3, thereby forming the microcavities 31. The advantage of this is that the microcavities 31 form an under-cut structure. In the subsequent deposition of the EL layer 6 and CGL film 7, the EL layer 6 and CGL film 7 will fall in the interval region between each anode, thereby making the CGL film 7 discontinuously distributed. It can also form multiple sub-units composed of anode layer 4, ITO film, EL layer 6 and CGL film 7, which can improve the current crosstalk between each anode and avoid current crosstalk. Between every two adjacent microcavities 31, a via 32 is provided that passes through the SIO layer 2 and the SIN layer 3. The via 32 extends from the CMOS substrate layer 1 to the anode layer 4. A metal connection layer is added to the via 32, thereby serving as the connection between the CMOS substrate layer 1 and the anode layer 4 in the OLED, enabling power supply to the silicon-based OLED. A portion 8 is provided in each microcavity 31.
[0018] Furthermore, the structure of the microcavity 31 can be adjusted by controlling the SIN / SIO etching selectivity ratio. It can be a square structure with both sides etched along the SIN direction, or, to improve the isolation effect, the microcavity 31 structure can be adjusted to have an arc shape, sharp edges, or a wavy shape. The etching depth on both sides can also be adjusted according to the actual product to ensure the isolation effect on the CGL film layer 7. To better achieve the discontinuous distribution of the CGL film layer 7, the size and morphology of the anode layer 4 can be adjusted during patterning etching to give its two sides a slight inclination. The above structure can be achieved through multiple thin film depositions, such as... Figure 2 As shown, during thin film deposition, multiple downwardly recessed portions can be formed when depositing the ITO film layer 5. Thus, when etching the ITO film layer 5, the anode layer 4 and the ITO film layer 5 naturally produce a tilt angle.
[0019] In the actual processing, firstly: S1: SiO layer 2 and SiN layer 3 are processed on CMOS substrate 1 by CVD evaporation, and then through hole 32 is formed. S2: A reflective layer is formed by PVD deposition of TI / TIN / Al / TIN, followed by multiple deposition and etching processes. Figure 2 The structure shows that the deposited ITO film 5 has multiple downwardly recessed portions; S3: Self-aligned anode etching is performed using a mask, with the etching location at the bottom of the recessed portion. When etching the anode, to ensure that each anode is etched through, the etching is selected to penetrate the SIN layer 3 and stop at the surface of the SIO layer 2. Then, the SIN / SIO etching selectivity ratio is adjusted to allow the SIN layer 3 to be etched laterally, forming an undercut structure to isolate the subsequently deposited CGL layer.
[0020] S4: Evaporation deposition of EL and CGL. Due to the presence of the undercut structure, the EL and CGL films will fall into the inter-anode spacers during the deposition process, forming... Figure 1 The remaining portion 8 shown makes the CGL discontinuous, which can effectively improve the electrical crosstalk between the anodes.
[0021] As is known from common technical knowledge, this utility model can be implemented through other embodiments that do not depart from its spirit or essential characteristics. Therefore, the disclosed embodiments described above are merely illustrative in all respects and are not the only ones. All modifications within the scope of this utility model or its equivalents are included in this utility model.
Claims
1. An under-cut structure in a silicon-based OLED, characterized in that, Set them separately along the vertical upward direction: CMOS substrate layer (1); SIO layer (2); SIN layer (3); Anode layer (4); ITO film layer (5); EL layer (6); CGL film (7); The SIN layer is provided with a plurality of microcavities (31) at equal intervals. Between each two adjacent microcavities (31) there is a via (32) that passes through the SIO layer (2) and the SIN layer (3). The via (32) extends from the CMOS substrate layer (1) to the anode layer (4).
2. The under-cut structure in the silicon-based OLED according to claim 1, characterized in that, An opening (33) smaller than the width of the microcavity (31) is provided above the microcavity (31). Multiple openings (33) simultaneously isolate the anode layer (4), ITO film layer (5), EL layer (6) and CGL film layer (7) and form multiple independent sub-units.
3. The under-cut structure in the silicon-based OLED according to claim 1, characterized in that, The microcavities have a square structure.
4. The under-cut structure in the silicon-based OLED according to claim 1, characterized in that, The two sides of the microcavity (31) extend in the lateral direction below the anode layer (4).
5. The under-cut structure in the silicon-based OLED according to claim 1, characterized in that, The microcavity (31) is formed by adjusting the SIN and SIO etching selectivity ratio so that the SIN layer (3) is etched laterally.
6. The under-cut structure in the silicon-based OLED according to claim 2, characterized in that, The sub-unit is configured as a trapezoidal structure that is narrower at the top and wider at the bottom.
7. The under-cut structure in the silicon-based OLED according to claim 2, characterized in that, The morphology of the through hole (32) is set to be wider at the top and narrower at the bottom.