WO2021169142A1

WO2021169142A1 - Structure of and producing method for silicon-based oled miniature display panel

Info

Publication number: WO2021169142A1
Application number: PCT/CN2020/101034
Authority: WO
Inventors: 赖耀升; 彭丰章; 江建志
Original assignee: 恩利克（浙江）智能装备有限公司
Priority date: 2020-02-28
Filing date: 2020-07-09
Publication date: 2021-09-02
Also published as: CN111192533A

Abstract

A structure of a silicon-based OLED miniature display panel, comprising a silicon substrate (1). TFTs are provided on the silicon substrate (1); anodes (8) are provided on the TFTs; white OLEDs (2) are provided on the anodes (8), and color filters (5) are provided above the white OLEDs (2); a glass substrate (6) is provided above the color filters (5); the white OLEDs (2) are provided on the anodes (8) by plating; the anodes (8) are provided on the TFTs by plating; the TFTs are provided on the silicon substrate (1) by plating; the color filters (5) are formed on the glass substrate (6); and the glass substrate (6) and the silicon substrate (1) are fixedly bonded by means of laser cladding. The color filters (5) are formed on the ultra-thin glass substrate (6), the white OLEDs (2) are provided on the silicon substrate (1) by plating, and bonding and laser cladding are then carried out; compared with the prior art, the TFP layer (multi-layer thin film packaging) (3) is canceled, and the color filters (5) are closer to the white OLEDs (2), such that the projection viewing angle of the white OLEDs (2) is expanded, thus widening the viewing angle of the silicon-based OLED miniature display panel, lowering the difficulty of the production process, and achieving ultra-high pixel density (>3000PPI).

Description

Structure and manufacturing method of silicon-based OLED micro display panel

Technical field

The invention belongs to the field of OLED display panels, and more specifically relates to a structure and manufacturing method of a silicon-based OLED micro display panel.

Background technique

The rapid development of modern electronic technology, especially the display technology, from the mature LCD to the now more and more widely used OLED, has now developed to flexible and bendable OLED display panels and silicon-based OLED micro display panels. Silicon-based OLED micro display panels use mature semiconductor CMOS technology to integrate high-density and complex drive circuits on monocrystalline silicon as an active drive backplane chip, and then match OLEDs to provide a single-chip micro-display solution . It has the characteristics of small size, light weight, high brightness, high contrast, high PPI, high integration, low response time, large viewing angle, wide operating temperature range and low power consumption. It is especially suitable for virtual reality such as AR/VR/MR. /Augmented/Mixed Reality scene near-eye display glasses and helmets.

From the structural point of view, the most obvious difference between silicon-based OLEDs and ordinary OLEDs is that the silicon-based OLED panels have removed the bottom glass plate and replaced them with silicon chips. It is mainly composed of IC manufacturing technology and OLED technology. It is different from traditional mobile phones, computers, and TV screens. Generally, the diagonal is less than 2 inches, and the pixel density is greater than 1500PPI.

Because monocrystalline silicon wafers are opaque, the structure of a silicon-based OLED must be designed as a top-emitting OLED, so that light is emitted through the translucent top electrode.

The pixel density of the micro display panel is very high, up to 2000PPI or more. The precision of the metal mask is insufficient. Generally, RGB side-by-side full-color panels are not used to make full-color panels, but white-light OLEDs and color filters are used to make full-color panels.

When the pixel density is increased to 2000～3000PPI, there will be no screen window effect when projected to the eyes. But the pixel size is only a few μm, which is an order of magnitude smaller than the thickness of the optical glue.

Figure 1 shows the first structure. The traditional method is to attach the color filter 5 (CF) to the silicon-based white light OLED 2 with optical glue 4, which is a glass substrate 6 and a color filter from top to bottom. Sheet 5, optical glue 4, multilayer film package 3, white light OLED2 and silicon substrate 1, but the optical glue is too thick, so that the viewing angle a is too small to increase the pixel density. Figure 2 shows the second structure. In order to improve the viewing angle and pixel resolution, SONY uses CF directly on the OLED (CF on OLED). Although the viewing angle a is increased, it must be in white light. The process of making CF on OLED (W-OLED) is very difficult: the temperature cannot exceed 100°C, and the wet process cannot be used.

Summary of the invention

In view of the shortcomings of the prior art, the present invention provides a color filter fabricated on an ultra-thin glass substrate, white light OLED is plated on the Si substrate, and then bonded and laser fused, which is less expensive than the prior art. The TFP layer (multi-layer thin film encapsulation) is removed, making the color filter closer to the white light OLED, which increases the white light OLED projection viewing angle, improves the viewing angle of the silicon-based OLED micro display panel, reduces the difficulty of the production process, and can produce ultra-high pixels Density (>3000PPI) miniature display panel.

In order to achieve the above objectives, the present invention provides the following technical solutions: a silicon-based OLED micro display panel structure, comprising a silicon substrate, a TFT is arranged above the silicon substrate, an anode is arranged on the TFT, and a white light OLED is arranged on the anode. A color filter is arranged above the white light OLED, and a glass substrate is arranged above the color filter.

Further, the white light OLED is plated on the anode, the anode is plated on the TFT, the TFT is plated on the silicon substrate, the color filter is made on a glass substrate, and the glass substrate and the silicon substrate are fixedly bonded by laser fusion sealing .

Further, the glass substrate is ultra-thin glass.

Furthermore, an explosion-proof film is arranged above the ultra-thin glass.

Further, the thickness of the ultra-thin glass is 30-150 microns.

Further, the thickness of the color filter is 2-4 microns.

A method for manufacturing a silicon-based OLED micro display panel includes the following steps:

S1: First coat BM on the glass substrate and dry, and then use the pigment dispersion method to make RGB three-color graphics on the BM to form a color layer;

S2: After the color layer is completely dried, SiO2 is plated on the surface of the color layer; then the outer ring of the color layer is screen printed or dot coated with glass paste and dried to form a color filter, and UV glue is applied to the edge of the color filter ；

S3: Fabricate TFT on a silicon substrate, then fabricate an anode on the TFT, and then fabricate an SiO2 insulating layer. The SiO2 insulating layer is coated with SiO2 on the anode spacing area and the periphery of the anode using the CVD/PVD method, and then dry engraved or etched to form SiO2 Insulating layer; then the white light OLED is plated on the anode, and the outer ring of the white light OLED is retained with an SiO2 insulating layer;

S4: Align the glass substrate in step S2 with the silicon substrate in step S3, make the color filter face the white light OLED, and cure the UV glue by UV; then use laser fusion to combine the glass paste on the outer ring of the color layer with the white light OLED The SiO2 in the outer ring is fused to complete the production.

Further, after step S1, the color layer and the top surface of the BM are ground and flattened.

Furthermore, in step S2, SiO2 is plated on the surface of the color layer by the CVD method.

Compared with the prior art, the beneficial effects of the present invention are:

1. Improve the viewing angle. Multi-layer film packaging still has a thickness of more than 10μm. The use of glass paste (Frit) packaging can make the white light OLED closer to the CF, improve the viewing angle, and can produce ultra-high pixel density (>3000PPI) Mini display panel;

2. The use of ultra-thin glass and ultra-thin silicon wafers allows the micro display panel to have a certain degree of curvature, reducing image distortion when applied near the eye;

3. Explosion-proof film is coated on the ultra-thin glass to prevent the glass from breaking and causing damage when an accident occurs;

4. It does not use multi-layer film encapsulation, which can save the costly investment in coating equipment for waterproof layer (overlay of organic layer and inorganic layer);

5. The process of making CF on white light OLED is very difficult: the temperature cannot exceed 100°C, and the wet process cannot be used. Adopting the process of directly making CF on the glass and then laminating it can greatly increase the yield rate.

Description of the drawings

Fig. 1 is a schematic diagram of the first structure in the prior art;

Figure 2 is a schematic diagram of a second structure in the prior art;

3 is a schematic diagram of the structure of the silicon-based OLED micro display panel of the present invention;

4 is a flow chart of the manufacturing method of the silicon-based OLED micro display panel of the present invention;

Fig. 5 is a schematic diagram when the glass substrate and the silicon substrate are not bonded;

Fig. 6 is a schematic diagram after the glass substrate and the silicon substrate are bonded.

Reference signs: 1. Silicon substrate; 2. White light OLED; 3. Multilayer film packaging; 4. Optical glue; 5. Color filter; 6. Glass substrate; 7. Explosion-proof film; 8. Anode.

Detailed ways

The embodiments of the present invention will be further described with reference to FIGS. 3 to 6.

In the description of the present invention, it should be noted that for orientation words, if there are the terms "center", "horizontal (X)", "longitudinal (Y)", "vertical (Z)", "length", " "Width", "Thickness", "Top", "Bottom", "Front", "Back", "Left", "Right", "Vertical", "Horizontal", "Top", "Bottom", "Inner" "," "outside", "clockwise", "counterclockwise" and other indicating orientations and positional relationships are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention 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, and cannot be construed as limiting the specific protection scope of the present invention.

In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. Therefore, the definition of "first" and "second" features may explicitly or implicitly include one or more of these features. In the description of the present invention, "several" and "several" mean two or two Above, unless otherwise specifically defined.

A structure of a silicon-based OLED micro display panel, comprising a silicon substrate 1, a TFT is arranged on the silicon substrate 1, an anode 8 is arranged on the TFT, and a white light OLED 2 is arranged on the anode 8, and a color filter is arranged on the white light OLED 2 Sheet 5, a glass substrate 6 is arranged above the color filter 5.

In this embodiment, the white light OLED2 is plated on the anode 8, the anode 8 is plated on the TFT, and the TFT is plated on the silicon substrate 1. The color filter 5 is made on the glass substrate 6, the glass substrate 6 and The silicon substrate 1 is fixed and bonded by laser fusion sealing.

The glass substrate 6 is ultra-thin glass with a thickness of 30-150 microns, and an explosion-proof film 7 is preferably provided on its upper surface.

In this embodiment, the silicon substrate 1 is made of ultra-thin silicon wafers with a thickness of about 200 micrometers; the thickness of the white light OLED 2 is about 1 micrometer; the thickness of the color filter 5 is 2-4 micrometers; so that the miniature display panel can have A certain degree of curvature reduces image distortion when applied near the eye.

S1: First, BM is coated on the glass substrate 6 and dried, and then RGB three-color graphics are made on the BM by the pigment dispersion method to form a color layer;

S2: After the color layer is completely dried, SiO2 is plated on the surface of the color layer; then the outer ring of the color layer is screen-printed or dot-coated with glass paste and dried to form a color filter 5, which is coated on the edge of the color filter 5. UV glue;

S3: Fabricate TFT on the silicon substrate 1, then fabricate the anode 8 on the TFT, and then fabricate the SiO2 insulating layer. The SiO2 insulating layer is coated with SiO2 on the interval area of the anode 8 and the periphery of the anode 8 by the CVD/PVD method, and then dry engraved Or etching to form a SiO2 insulating layer; then the white light OLED2 is plated on the anode 8, and the outer ring of the white light OLED2 retains the SiO2 insulating layer;

S4: Align the glass substrate 6 in step S2 with the silicon substrate 1 in step S3, and make the color filter 5 face the white light OLED2, and cure the UV glue by UV; then use laser fusion to bond the glass paste of the outer ring of the color layer It is fused with the SiO2 of the outer ring of the white light OLED2 to complete the production.

In this embodiment, Cr is preferably used as the BM material. Preferably, after step S1, the color layer and the top surface of the BM are smoothed and flattened.

In step S2, SiO2 is plated on the surface of the color layer by the CVD method.

In step S2, if multiple color filters 5 are produced on an ultra-thin glass substrate 6 at the same time in the actual production process, then UV glue is applied to the spaced area of the color filter 5 at this time; after step S4 , It is preferable to perform the cutting step, and then enter the normal module manufacturing process.

The above are only the preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments. All technical solutions under the idea of the present invention belong to the protection scope of the present invention. It should be pointed out that for those of ordinary skill in the art, several improvements and modifications made without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

A structure of a silicon-based OLED miniature display panel, comprising a silicon substrate, characterized in that: a TFT is arranged above the silicon substrate, an anode is arranged on the TFT, a white light OLED is arranged on the anode, and a white light OLED is arranged above the white OLED There is a color filter, and a glass substrate is arranged above the color filter.
The structure of the silicon-based OLED micro display panel according to claim 1, wherein the white light OLED is plated on an anode, the anode is plated on a TFT, the TFT is plated on a silicon substrate, and the color filter The optical sheet is fabricated on a glass substrate, and the glass substrate and the silicon substrate are fixedly bonded by laser fusion sealing.
The structure of the silicon-based OLED micro display panel according to claim 2, wherein the glass substrate is ultra-thin glass.
The structure of the silicon-based OLED micro display panel according to claim 3, wherein an explosion-proof film is provided on the ultra-thin glass.
The structure of the silicon-based OLED micro display panel according to claim 4, wherein the thickness of the ultra-thin glass is 30-150 microns.
The structure of the silicon-based OLED micro display panel according to claim 5, wherein the thickness of the color filter is 2-4 micrometers.
A method for manufacturing a silicon-based OLED micro display panel, which is characterized in that it comprises the following steps:

S1: First coat BM on the glass substrate and dry, and then use the pigment dispersion method to make RGB three-color graphics on the BM to form a color layer;

S2: After the color layer is completely dried, SiO2 is plated on the surface of the color layer; then the outer ring of the color layer is screen printed or dot coated with glass paste and dried to form a color filter, and UV glue is applied to the edge of the color filter ；

S3: Fabricate TFT on a silicon substrate, then fabricate an anode on the TFT, and then fabricate an SiO2 insulating layer. The SiO2 insulating layer is coated with SiO2 on the anode spacing area and the periphery of the anode using the CVD/PVD method, and then dry engraved or etched to form SiO2 Insulating layer; then the white light OLED is plated on the anode, and the outer ring of the white light OLED is retained with an SiO2 insulating layer;

S4: Align the glass substrate in step S2 with the silicon substrate in step S3, make the color filter face the white light OLED, and cure the UV glue by UV; then use laser fusion to combine the glass paste on the outer ring of the color layer with the white light OLED The SiO2 in the outer ring is fused to complete the production.
8. The method for manufacturing a silicon-based OLED micro display panel according to claim 7, characterized in that: after step S1, the color layer and the top surface of the BM are ground and flattened.
8. The method for manufacturing a silicon-based OLED micro display panel according to claim 8, wherein in step S2, SiO2 is plated on the surface of the color layer by a CVD method.