CN220172130U - Pixel unit, micro display screen and pixel unit discrete device - Google Patents

Abstract

The utility model discloses a pixel unit, a micro display screen and a pixel-separated device, wherein the pixel unit comprises a driving backboard and a display unit, the display unit comprises a first device layer, a second device layer and a third device layer which are vertically stacked in sequence, the first device layer comprises at least one first sub-pixel, the second device layer comprises at least one second sub-pixel, the third device layer comprises at least one third sub-pixel, the projection of the first sub-pixel on the driving backboard, the projection of the second sub-pixel on the driving backboard and the projection of the third sub-pixel on the driving backboard are not overlapped; the second device layer and the third device layer also respectively comprise color conversion layers, the color conversion layers included in different device layers are vertically stacked in sequence, and the projection of the first sub-pixel on the driving backboard is positioned in the projection of any color conversion layer on the driving backboard; the pixel unit can effectively increase the thickness of the color conversion layer group so as to improve the brightness of the light source obtained by color conversion and the color purity of the light source obtained by color conversion.

Description

Pixel unit, micro display screen and pixel unit discrete device

Technical Field

The utility model relates to the technical field of semiconductor devices, in particular to a pixel unit, a micro display screen and a pixel discrete device.

Background

With the development of Micro-LED display technology, a new technological breakthrough is still expected in the colorization display direction. In a colorized display, the common proportion of three colors of red (R), green (G) and blue (B) is generally 35% of red light, 50% of green light and 15% of blue light. In the three primary color technology, the brightness of blue light and green light can be generally met, but red light is limited in performance, luminous efficiency and brightness, and high-performance Micro LED red light meeting the requirements is difficult to realize. In addition, when a GaAs substrate is adopted As a red light source in the three primary colors technology, the problem of As pollution is brought.

For this reason, blue/green InGaN compounds are commonly used as excitation light sources in the prior art to form red light sources in combination with color conversion layers formed of red light quantum dot materials. The existing Micro-LED colorization structure is generally red, green and blue sub-pixels distributed horizontally or distributed in the coaxial vertical direction, however, it is difficult to ensure that the color conversion layer has a sufficient depth-to-width ratio in any of the above structures. When the thickness of the color conversion layer is insufficient, the light absorption conversion efficiency of the color conversion layer is low, and the brightness of the formed red light source is low. The color conversion layer formed by the current technology is thinner, the color conversion efficiency is less than 40%, and the brightness can only reach below 100000 nits. Compared with the standard that the color conversion efficiency is 85% under the condition of 10-20 mu m of the color conversion layer in a medium-and large-sized display, the color conversion efficiency of the traditional micro-display is at a lower level under the limits of structure and process, and the micro-display needs to be improved. As in the issued chinese patent CN114899291B, a portion of the sub-pixels are vertically stacked and combined with color conversion to realize a colorized display, and the color conversion layer is thinner in the structure, which has been verified to have a color conversion efficiency of 35%.

In addition, when the color conversion layer is thin, there is also an abnormal color purity of the target light source when the excitation light source is mixed with the target light source due to the fact that the excitation light source is transmitted through the color conversion layer, for example, when blue light is converted into red light, a large amount of leaked red light after blue light mixing color conversion can cause red light to be biased to powder or yellow, and abnormal half-wave width can cause abnormal colorization.

Therefore, a pixel unit capable of effectively overcoming the above-mentioned defects is needed.

Disclosure of Invention

The utility model aims to provide a pixel unit, a micro display screen and a pixel discrete device, wherein the pixel unit can maximally improve the depth-to-width ratio of a color conversion layer so as to improve the brightness of a converted light source and the color purity of the converted light source.

To achieve the above object, a first aspect of the present utility model provides a pixel unit, including:

a drive back plate;

the display unit is arranged on the driving backboard, and comprises a first device layer, a second device layer and a third device layer which are vertically stacked in sequence, wherein the first device layer comprises at least one first sub-pixel, the second device layer comprises at least one second sub-pixel, the third device layer comprises at least one third sub-pixel, the projection of any first sub-pixel on the driving backboard, the projection of any second sub-pixel on the driving backboard and the projection of any third sub-pixel on the driving backboard are not overlapped in pairs;

the second device layer and the third device layer further respectively comprise at least one color conversion layer, any one color conversion layer included in the second device layer and any one color conversion layer included in the third device layer are sequentially stacked on one side, far away from the driving backboard, of any one first sub-pixel, and the projection of any one first sub-pixel on the driving backboard is located in the projection of any one color conversion layer on the driving backboard.

In a preferred embodiment, the first device layer further includes at least one color conversion layer, and any one of the first sub-pixels is embedded in any one of the color conversion layers included in the first device layer.

In a preferred embodiment, any one of the first sub-pixels, any one of the second sub-pixels and any one of the third sub-pixels are respectively one of hemispherical structures or semi-ellipsoidal structures.

In a preferred embodiment, the ratio of the sum of the depths of all the color conversion layers in the display unit to the sum of the widths of all the color conversion layers in the display unit is not less than 1:1.

In a preferred embodiment, any one of the first sub-pixels has a larger volume than the other sub-pixels, and is connected to at least two anodes included in the driving back plate.

In a preferred embodiment, the first device layer further includes a first passivation layer and a first ohmic layer;

the first passivation layer is covered on the surface of any one of the first sub-pixels;

the first ohmic layer is arranged on the surface of the first passivation layer in a covering mode, penetrates through the first passivation layer and is respectively connected with any one of the first sub-pixels.

In a preferred embodiment, the display unit further includes at least one reinforcing structure, and any reinforcing structure is disposed in a circumferential direction of the first sub-pixel and/or the second sub-pixel and/or the third sub-pixel.

In a preferred embodiment, the second device layer further includes a second passivation layer and a second ohmic layer, where the second ohmic layer is covered on the surface of the second passivation layer, and the second ohmic layer passes through the second passivation layer and is respectively connected with any one of the second sub-pixels;

one end of the reinforcing structure surrounding any one of the first sub-pixels is connected with the first ohmic layer, and the other end of the reinforcing structure penetrates through the first passivation layer and is connected with the second ohmic layer.

In a preferred embodiment, the pixel unit further includes a light screen layer, and the light screen layer is disposed on a side of the display unit away from the driving back plate.

In a second aspect, a micro display is provided, the micro display comprising:

the micro display screen backboard comprises a driving circuit, an input interface and an output interface;

the display area is arranged on the micro display screen backboard, and comprises at least two display units which are arranged in an array mode and are included by the pixel units according to any one of the first aspect;

and the peripheral common cathode is electrically connected with each display unit respectively.

In a third aspect, there is provided a pixel level discrete device comprising:

a discrete device backplate comprising at least two anode pads and at least one cathode pad;

the device main body is arranged on the discrete device backboard, and comprises at least two display units which are arranged in an array mode and are included in the pixel unit according to any one of the first aspect.

Compared with the prior art, the utility model has the following beneficial effects:

the utility model provides a pixel unit, a micro display screen and a pixel discrete device, wherein the pixel unit comprises a driving backboard and a display unit, the display unit is arranged on the driving backboard, the display unit comprises a first device layer, a second device layer and a third device layer which are vertically stacked in sequence, the first device layer comprises at least one first sub-pixel, the second device layer comprises at least one second sub-pixel, the third device layer comprises at least one third sub-pixel, the projection of any first sub-pixel on the driving backboard, the projection of any second sub-pixel on the driving backboard and the projection of any third sub-pixel on the driving backboard are not overlapped; the second device layer and the third device layer also respectively comprise at least one color conversion layer, any color conversion layer comprised by the second device layer and any color conversion layer comprised by the third device layer are sequentially stacked on one side of any first sub-pixel far away from the driving backboard, and the projection of the first sub-pixel on the driving backboard is positioned in the projection of any color conversion layer on the driving backboard; the pixel units in the utility model realize the color conversion layer with larger depth-to-width ratio by combining the mode of the color conversion structure on the premise of dislocation arrangement among different sub-pixels of different device layers, and compared with the mode that each sub-pixel is horizontally arranged or each sub-pixel is coaxially and vertically stacked in the prior art, the thickness of the color conversion layer group can be effectively increased, larger color conversion efficiency is realized to improve the brightness of a light source obtained by color conversion, and light leakage is avoided to improve the color purity of the light source obtained by color conversion; in the utility model, the sub-pixels in different device layers are arranged in a staggered manner in the horizontal direction, and compared with the coaxial vertical stacking mode of the sub-pixels, the optical crosstalk problem caused by photoexcitation can be effectively avoided;

the utility model provides a pixel unit, wherein any first sub-pixel, any second sub-pixel and any third sub-pixel are respectively in one of a hemispherical structure or a semi-ellipsoidal structure; the utility model increases the light extraction efficiency by adopting a hemispherical sub-pixel or a semi-ellipsoidal sub-pixel, and improves the brightness by more than 30 percent;

the display unit in the pixel unit further comprises at least one enhancement structure, wherein any enhancement structure is arranged in the circumferential direction of the first sub-pixel and/or the second sub-pixel and/or the third sub-pixel; according to the utility model, the metal shielding among the sub-pixels is realized by arranging at least one enhancement structure, so that the optical crosstalk is effectively avoided, the structural reliability is improved, and the depth-to-width ratio is further improved; further, an ohmic layer between different device layers is connected by adopting an enhancement structure so as to further realize the common cathode of the whole display unit;

it should be noted that, the present utility model only needs to achieve at least one of the above technical effects.

Drawings

Fig. 1 is a top view of a pixel unit in embodiment 1;

FIG. 2 is a cross-sectional view of the section A-B of FIG. 1 in a configuration;

FIG. 3 is a cross-sectional view of section A-B of FIG. 1 in yet another configuration;

FIG. 4 is a cross-sectional view of section A-B of FIG. 1 in yet another configuration;

FIG. 5 is an exemplary driving circuit block diagram;

FIG. 6 is an exemplary circuit block diagram corresponding to a device layer;

FIG. 7 is a top view of the drive backplate;

FIG. 8 is a schematic diagram of the structure of a micro display in embodiment 2;

fig. 9 is a schematic diagram of the structure of a pixel-level discrete device in embodiment 3.

Reference numerals:

100-pixel cell, 10-drive back plane, 11-anode, 20-display cell, 21-interconnect via, 30-first device layer, 31-first sub-pixel, 32-first passivation layer, 33-first ohmic layer, 34-first conductive layer, 40-second device layer, 41-second sub-pixel, 42-second passivation layer, 43-second ohmic layer, 44-second conductive layer, 50-third device layer, 51-third sub-pixel, 52-third passivation layer, 53-third ohmic layer, 54-third conductive layer, 60-color conversion layer, 70-medium filling layer, 81-enhancement structure, 82-anode electrical connection structure, 90-light screen layer, 200-micro display screen, 300-micro display screen back plane, 400-display area, 500-peripheral common cathode, 600-external IO interface, 700-pixel level discrete device, 710-discrete device back plane, 720-device body, 730-anode pad.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present utility model more apparent, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model, and it is apparent that the described embodiments are only some embodiments of the present utility model, not all embodiments of the present utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

In the description of the present utility model, it should be understood that the directions or positional relationships indicated by the terms "upper", "lower", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of description of the present utility model and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present utility model, unless otherwise indicated, the meaning of "a plurality" is two or more.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "connected," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

Example 1

As shown in fig. 1 to 4, the present embodiment provides a pixel unit 100, and the pixel unit 100 is used for a semiconductor device, including but not limited to Micro-LEDs, micro-lasers, and other optoelectronic devices. The pixel unit 100 includes a driving back plate 10 and a display unit 20 disposed on the driving back plate 10.

The driving backplate 10 in this embodiment may be one or more active backplates combined with Thin Film Transistors (TFTs), low Temperature Polysilicon (LTPS), CMOS integrated circuits, high mobility transistors (HEMTs), etc. Specifically, the driving back plate 10 is provided with a driving circuit, and the driving circuit 10 is provided with at least one anode 11, and the circuit structure of the driving circuit is shown in fig. 5, which includes three or more scanning lines each corresponding to one sub-pixel, for example, in a structure including redundant sub-pixels. It should be noted that, the circuit diagram shown in the embodiment is only a simple schematic diagram. The driving circuit may comprise an active, passive or semi-passive control circuit, such as an exemplary circuit diagram of any of the device layers shown in fig. 6. All anodes 11 included in the driving circuit may be arranged linearly or in an array, and any anode 11 is located in the middle or at the edge of the driving back plate 10, which is not limited in this embodiment.

For convenience of description, the number of anodes 11 included in the driving circuit in the driving back plate 10 in this embodiment is four, and the four anodes 11 are arranged in an array, as shown in fig. 7.

In some embodiments, the drive backplate 10 comprises at least one Top Metal (Top Metal) covering at least one anode 11; alternatively, the drive backplate 10 includes an in-situ mirror disposed on an upper surface thereof, the in-situ mirror covering or uncovering at least one anode 11. The in-situ mirror may be a metal such as aluminum, gold, silver, etc.; the Bragg reflection layer can also be formed by stacking two or more films with different refractive indexes, such as a lamination of silicon oxide and titanium oxide, a lamination of silicon oxide and aluminum oxide, a lamination of silicon oxide and silicon nitride, and the like; it may also be an ODR total reflection mirror of a metal and dielectric stack, such as at least one combination of silver and silicon oxide, aluminum and aluminum oxide, gold and silicon oxide. Of course, in some embodiments, the driving backplate 10 includes a Top through hole (Top Via) corresponding to each anode 11.

With continued reference to fig. 2-4, the display unit 20 includes at least three device layers vertically stacked in sequence in a direction away from the drive backplate 10. In one embodiment, the display unit 20 includes a first device layer 30, a second device layer 40, and a third device layer 50 disposed in sequence in a direction away from the drive backplate 10. Wherein the first device layer 30 comprises at least one first sub-pixel 31, the second device layer 40 comprises at least one second sub-pixel 41, and the third device layer 50 comprises at least one third sub-pixel 51. In order to realize colorization display, especially white light display, different sub-pixels of different device layers respectively emit red light (R), green light (G) and blue light (B).

Aiming at the problem that the red sub-pixel formed by a red light InGaN ternary material system or a quaternary AlGaInP red light compound of a GaAs substrate in the prior art cannot meet the brightness due to limited performanceIn the pixel unit 100 of the present embodiment, the projection of any first sub-pixel 31 on the driving back plate 10, the projection of any second sub-pixel 41 on the driving back plate 10, and the projection of any third sub-pixel 51 on the driving back plate 10 are not overlapped, and the second device layer 40 and the third device layer 50 further include at least one color conversion layer 60 respectively, and any color conversion layer 60 included in the second device layer 40 and any color conversion layer 60 included in the third device layer 50 are sequentially stacked on one side of any first sub-pixel 31 far from the driving back plate 10, wherein the projection of any first sub-pixel 31 on the driving back plate 10 is located in the projection of any color conversion layer 60 on the driving back plate 10, as shown in fig. 2. Wherein, any color conversion layer 60 adopts red light quantum dot material or red fluorescent powder material, wherein the red light quantum dot material can be perovskite red light quantum dot, and the quantum dot material can be CsPdI ₃ At least one of a material, inP material, cdSe or CdS material.

Therefore, compared with the existing sub-pixels which are coaxially and vertically stacked and are easily affected by photoexcitation to cause optical crosstalk, or the phenomenon that different optical screen structures are required to be arranged inside the device layer to avoid optical crosstalk but inevitably bring about optical performance loss is avoided, the pixel unit 100 in the embodiment can effectively avoid the problem of optical crosstalk caused by photoexcitation among the sub-pixels.

The first sub-pixel 31 is an excitation light source, and is made of blue/green InGaN compound, and emits blue or green light. The excitation light emitted by any one of the first sub-pixels 31 is absorbed by at least two color conversion layers 60 located directly above the excitation light to be converted into red light. Therefore, the color conversion layer group (superposition of all the color conversion layers 60) located directly above any one of the first sub-pixels 31 is used for color conversion of the excitation light source emitted by that first sub-pixel 31. Of course, when more device layers are further included above the third device layer 50 and each device layer includes the same color conversion layer 60, the color conversion layer 60 is the same color conversion layer 60 of the first sub-pixel 31, and participates in the color conversion of the first sub-pixel 31 to further improve the performance of the converted light source, which is not limited in this embodiment.

Further, to avoid light leakage from the side of the color conversion layer 60 by the excitation light source of the first sub-pixel 31, in a preferred embodiment, the projection of any color conversion layer 60 onto the driving back plate 10 is larger than the projection of the corresponding first sub-pixel 31 onto the driving back plate 10.

The first sub-pixel 31, the second sub-pixel 41 and the third sub-pixel 51 are respectively one of hemispherical structures or semi-ellipsoidal structures. The sub-pixel with the structure can effectively improve the light extraction efficiency, and the brightness of the formed light source is improved by more than 30 percent.

As further preferred, as shown in fig. 4, the first device layer 30 further includes at least one color conversion layer 60, and any one of the first sub-pixels 31 is embedded in any one of the color conversion layers 60 included in the first device layer 30. Since the light emitting surface of the sub-pixel with the hemispherical structure or the semi-ellipsoidal structure is larger, the color conversion layer 60 covering the entire light emitting surface of the first sub-pixel 31 is disposed in the first device layer 30, so as to maximize the absorption of the excitation light source and avoid the light leakage of the excitation light source, and further increase the sum of thicknesses of the color conversion layer groups corresponding to the first sub-pixel 31, so as to increase the depth-to-width ratio of the color conversion layer groups.

The ratio of the sum of the depths of the color conversion layer groups in the display unit 20 to the sum of the widths of the color conversion layer groups in the display unit 20 is not less than 1:1. Note that, the aspect ratio in the present embodiment refers to the color conversion layer group obtained by summing the color conversion layer groups corresponding to the same first sub-pixel 31 in the vertical direction, that is, the color conversion layer group. Specifically, when only the second device layer 40 and the third device layer 50 each include the corresponding color conversion layer 60, the aspect ratio is not less than 1:1; when the first device layer 30 also includes the color conversion layer 60, the aspect ratio is not less than 3:1.

Therefore, compared with the scheme that each sub-pixel is horizontally arranged or each sub-pixel is coaxially and vertically stacked in the prior art, the pixel unit 100 in the embodiment realizes the color conversion layer group with a larger depth-to-width ratio by combining the multi-layer color conversion layer 60 on the premise that different sub-pixels of different device layers are arranged in a staggered manner, can effectively increase the thickness of the color conversion layer group, realize a larger color conversion efficiency to improve the brightness of the light source obtained by color conversion, and can avoid light leakage to improve the color purity of the light source obtained by color conversion.

On this basis, in a preferred embodiment, any one of the first sub-pixels 31 has a larger volume than the remaining sub-pixels, and any one of the first sub-pixels 31 is simultaneously connected to at least two anodes 11 included in the driving back plate 10 to obtain more energy. This embodiment increases the brightness of the converted red light source by increasing the volume of the sub-pixels to increase the brightness of the excitation light source. In another embodiment, as shown in fig. 2-4, the first device layer 30 includes at least two first sub-pixels 31, each first sub-pixel 31 being connected to a different anode 11. This embodiment increases the brightness of the excitation light source by providing redundant sub-pixels to increase the brightness of the converted red light source. Of course, when the number of first sub-pixels 31 is increased, the number of color conversion layers 60 corresponding thereto is also increased.

On this basis, the second sub-pixel 41 and the third sub-pixel 51 are each one of a green light source and a blue light source, which is not limited in this embodiment. Typically, the second sub-pixel 41 and the third sub-pixel 51 are made of InGaN material system. Compared with the current situation that the sub-pixels in the prior art are required to be distributed from bottom to top in the coaxial vertical stacking scheme, so as to avoid the light absorption problem, the distribution of each sub-pixel in the vertical direction is not limited by adopting the sub-pixel dislocation arrangement mode in the embodiment. Illustratively, the second sub-pixel 41 is fabricated using a blue InGaN material system and the third sub-pixel 51 is fabricated using a green InGaN material system.

As shown in fig. 2 to 4, the first device layer 30 further includes a first passivation layer 32, a first ohmic layer 33, a dielectric filling layer 70, and at least one enhancement structure 81, the first passivation layer 32 is covered on the surface of any one of the first sub-pixels 31, the first ohmic layer 33 is covered on the surface of the first passivation layer 32, and the first ohmic layer 33 penetrates through the first passivation layer 32 and is respectively connected to any one of the first sub-pixels 31. Therefore, the first ohmic layer 33 and the first passivation layer 32 are both in the whole structure, and the first passivation layer 32 is provided with at least one opening corresponding to each of the first sub-pixels 31, the first ohmic layer 33 is attached to the first passivation layer 32, and the portion of the first ohmic layer 33 located in the corresponding opening is attached to the first sub-pixel 31. The second device layer 40 also includes a second passivation layer 42, a second ohmic layer 43, a dielectric fill layer 70, and at least one enhancement structure 81, which are structurally identical to the first device layer 30. And the second ohmic layer 43 is disposed on the surface of the second passivation layer 42, and the second ohmic layer 43 penetrates through the second passivation layer 42 and is connected to any one of the second sub-pixels 42 respectively. Likewise, the third device layer 50 further includes a third passivation layer 52, a third ohmic layer 53, a dielectric fill layer 70, and at least one enhancement structure 81. Similarly, the third ohmic layer 53 is disposed on the surface of the third passivation layer 52, and the third ohmic layer 53 penetrates through the third passivation layer 52 and is connected to any one of the third sub-pixels 51 respectively. In this embodiment, the ohmic layer with the whole structure is used to realize the common cathode of all the sub-pixels in the same device layer, and even realize the common cathode between the same device layers between adjacent sub-pixels in the subsequent semiconductor device.

As described above, any passivation layer in this embodiment is made of a transparent dielectric material, and any ohmic layer is made of a transparent conductive material, such as ITO, znO, and the like.

The dielectric filling layer 70 included in each device layer is used for filling and flattening the device layer, and the dielectric filling layer 70 is made of a transparent dielectric material, wherein the transparent dielectric material comprises a single layer or multiple layers of inorganic dielectric materials such as silicon oxide, silicon nitride, aluminum oxide, titanium oxide, diamond and the like, or can be an organic dielectric material such as SU8, polyimide and the like, or can be a polycrystalline material such as glass, soda and the like.

The display unit 20 further includes a plurality of conductive layers and a plurality of anode electrical connection structures 82, and the anode electrical connection of any sub-pixel is realized by the conductive layers and the anode electrical connection structures 82 in a matching manner. Wherein at least one anode electrical connection structure 82 corresponding to any one sub-pixel is located below the sub-pixel, and a projection of any anode electrical connection structure 82 on the driving back plate 10 is located within a projection of the sub-pixel on the driving back plate 10. In the vertical non-coaxial stacking scheme in the prior art, the anode electrical connection structure needs to be carried out from the side wall, and the disadvantage brought by the structure is that the anode electrical connection structure arranged at the side direction influences the luminous area occupation ratio of the sub-pixels. Therefore, the mode of arranging the anode electrical connection structure below the sub-pixel can effectively improve the photoelectric conversion efficiency of the sub-pixel, increase the light emitting area occupation ratio of the sub-pixel and effectively improve the structural reliability.

Any device layer includes one or more conductive layers corresponding to any sub-pixel in the present device layer, the upper device layer. Specifically, when the first device layer 30 is provided with at least two first sub-pixels 31, the first device layer 30 further includes at least four first conductive layers 34, and each first conductive layer 34 is disposed between the anode 11 and the corresponding sub-pixel. At least two of the first conductive layers 34 are used for anode connection of two of the first sub-pixels 31, and the remaining at least two first conductive layers 34 are used for anode connection of the second sub-pixel 41 or the third sub-pixel 51, respectively.

And, the second device layer 40 is provided with at least one second conductive layer 44, and the third device layer 50 is also provided with at least one third conductive layer 54. An anode electrical connection structure 82 included in the first device layer 30 is connected at one end to the second conductive layer 44 and at the other end through the dielectric fill layer 70 of the first device layer 30 and to the corresponding first conductive layer 34. Any one of the second sub-pixels 41 is connected to the corresponding anode via the second conductive layer 44, the anode electrical connection structure 82 and the first conductive layer 34 disposed thereunder in order. Likewise, the same is true. Any one of the third sub-pixels 51 is connected to the corresponding anode via the third conductive layer 54, the anode electrical connection structure 82, the second conductive layer 44, the anode electrical connection structure 82, and the first conductive layer 34, which are sequentially disposed thereunder.

Wherein the first conductive layer 34, the second conductive layer 44, the third conductive layer 54, and the anode electrical connection structure 82 are all made of metal conductive materials. The conductive layer made of the metal material is adopted to form the metal shielding in the vertical direction, so that optical crosstalk between different sub-pixels can be effectively reduced. Preferably, the first conductive layer 34 is made of a transparent conductive material such as ITO or ZnO, or a laminate or alloy of a metal material such as Ni, au or Ag, and the second conductive layer 44 and the third conductive layer 54 are made of a transparent conductive material such as ITO or ZnO, respectively.

Any of the reinforcing structures 81 is disposed in the circumferential direction of the first sub-pixel 31 and/or the second sub-pixel 41 and/or the third sub-pixel 51, so as to realize metal shielding between the sub-pixels and avoid optical crosstalk. On this basis, as a further preferable aspect, the second device layer 40 and the third device layer 50 further include corresponding reinforcing structures 81 corresponding to the reinforcing structures 81 surrounding the first sub-pixel 31 in the circumferential direction, and the reinforcing structures 81 surrounding any color conversion layer 60 in any device layer are further included to further avoid light leakage of the excitation light source. Preferably, the enhancement structures 81 in the first sub-pixel 31 are aligned end to end in the vertical direction of the driving backplate 10 with the associated enhancement structures 81 in any device layer above.

One end of any reinforcing structure 81 close to the driving back plate 10 is connected with the ohmic layer of the device layer where the reinforcing structure is located, and the other end extends in a direction away from the driving back plate 10. For example, one end of the reinforcing structure 81 of the first device layer 30 is connected to the first passivation layer 32. As a further preference, the reinforcing structures 81 extend in a direction away from the drive backplate 10 to extend through the respective device layers. For example, the reinforcing structure 81 surrounding the periphery of any one of the first sub-pixels 31 in the first device layer 30 extends in the vertical direction of the driving backplate 10 to be connected with the second passivation layer 42 of the second device layer 40. Still further, the enhancement structure 81 extends through the passivation layer of the previous device layer to connect with the ohmic layer. For example, the reinforcing structure 81 surrounding any one of the first sub-pixels 31 in the first device layer 30 extends through the second passivation layer 42 of the second device layer 40 and is connected to the second ohmic layer 43, and the second passivation layer 42 is provided with an interconnection via 21 for facilitating the penetration of the reinforcing structure 81. Thus, this embodiment achieves cathode interconnection between different device layers in the same pixel cell 100 through the enhancement structure 81. Of course, the third device layer 50 is also provided with an interconnection via 21 for facilitating the penetration of the enhancement structure 81, which will not be described here again.

Further, the thickness of any reinforcing structure 81 and any anode electrical connection structure 82 decreases from one end close to the driving back plate 10 to the other end, forming a bowl-cup shape with a trapezoid cross section, which can effectively improve the structural reliability and effectively support the color conversion layer 60 formed in the reinforcing structure 81. Preferably, the reinforcing structure 81 and the anode electrical connection structure 82 are both made of a metal simple substance such as Al, ti, cu, tiW or a metal composite material.

As shown in fig. 3 and 4, the pixel unit 100 further includes the light screen layer 90, and the light screen layer 90 is disposed on a side of the display unit 20 away from the driving back plate 10. In one embodiment, the light screen layer 90 is disposed only above the color conversion layer 60, and in another embodiment, the light screen layer 90 has a whole structure to improve the flatness of the surface of the pixel unit 100. The arrangement of the light screen layer 90 can effectively reduce the half-wave width of the wavelength caused by color conversion and further improve the color purity.

Example 2

The present embodiment provides a micro display 200, as shown in fig. 8, the micro display 200 includes:

the micro display screen backboard 300, the micro display screen backboard 300 comprises at least two driving circuits, an input interface and an output interface;

the display area 400 is disposed on the micro display back plate 300, and the display area 400 includes at least two display units 20 of the pixel units 100 as in embodiment 1, and at least two display units 20 are arranged in an array;

the peripheral common cathode 500, the peripheral common cathode 500 is electrically connected to any one of the ohmic layers included in each of the display units 20, respectively, so that the entire micro display 200 is common to the cathodes. It should be noted that, the peripheral common cathode 500 is a metal frame structure surrounding the display area 400.

The external IO interface 600 is located at an arbitrary position of the micro display screen backboard 300.

Further, the arrangement direction of each pixel unit 100 in the micro display 200 that is arranged adjacently is not limited in this embodiment.

The specific structure and corresponding technical effects of the micro display in this embodiment are described in detail with reference to embodiment 1, which will not be described in further detail.

Example 3

As shown in fig. 9, the present embodiment provides a pixel-level discrete device 700, the pixel-level discrete device 700 including:

a discrete device backplane 710, the discrete device backplane 710 comprising at least three anode pads 730 and at least one cathode pad (not shown);

the device body 720, the device body 720 is disposed on the discrete device back plane 710, and the device body 720 includes at least two display units 20 as the pixel unit 100 in embodiment 1, and the at least two display units 20 are arranged in an array. And, any one of the first conductive layers 34 is connected to a corresponding anode pad 730, and the ohmic layer of any one of the device layers is connected to a corresponding cathode pad.

All the above optional technical solutions can be combined to form an optional embodiment of the present utility model, and any multiple embodiments can be combined, so as to obtain the requirements of coping with different application scenarios, which are all within the protection scope of the present utility model, and are not described in detail herein.

It should be noted that the above-mentioned embodiments are only preferred embodiments of the present utility model, and are not intended to limit the present utility model, and any modifications, equivalent substitutions, improvements, etc. within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims (11)

1. A pixel cell, wherein the pixel cell comprises:

a drive back plate;

the display unit is arranged on the driving backboard, and comprises a first device layer, a second device layer and a third device layer which are vertically stacked in sequence, wherein the first device layer comprises at least one first sub-pixel, the second device layer comprises at least one second sub-pixel, the third device layer comprises at least one third sub-pixel, the projection of any first sub-pixel on the driving backboard, the projection of any second sub-pixel on the driving backboard and the projection of any third sub-pixel on the driving backboard are not overlapped in pairs;

the second device layer and the third device layer further respectively comprise at least one color conversion layer, any one color conversion layer included in the second device layer and any one color conversion layer included in the third device layer are sequentially stacked on one side, far away from the driving backboard, of any one first sub-pixel, and the projection of any one first sub-pixel on the driving backboard is located in the projection of any one color conversion layer on the driving backboard.

2. The pixel cell of claim 1, wherein the first device layer further comprises at least one of the color conversion layers, wherein any of the first sub-pixels is embedded within any of the color conversion layers comprised by the first device layer.

3. The pixel unit of claim 1, wherein any one of the first sub-pixel, any one of the second sub-pixel, and any one of the third sub-pixel is one of a hemispherical structure or a semi-ellipsoidal structure, respectively.

4. A pixel cell according to any one of claims 1 or 2, wherein the ratio of the sum of the depths of all the color conversion layers in the display cell to the sum of the widths of all the color conversion layers in the display cell is not less than 1:1.

5. The pixel cell of claim 4, wherein any one of the first sub-pixels has a larger volume than the remaining sub-pixels, and wherein any one of the first sub-pixels is simultaneously connected to at least two anodes included in the driving back plate.

6. The pixel cell of claim 1, wherein the first device layer further comprises a first passivation layer and a first ohmic layer;

the first passivation layer is covered on the surface of any one of the first sub-pixels;

the first ohmic layer is arranged on the surface of the first passivation layer in a covering mode, penetrates through the first passivation layer and is respectively connected with any one of the first sub-pixels.

7. The pixel cell of claim 6, wherein the display cell further comprises at least one enhancement structure, any of the enhancement structures being disposed circumferentially of the first sub-pixel and/or the second sub-pixel and/or the third sub-pixel.

8. The pixel cell of claim 7, wherein the second device layer further comprises a second passivation layer and a second ohmic layer, the second ohmic layer is disposed on the surface of the second passivation layer, and the second ohmic layer passes through the second passivation layer and is respectively connected to any one of the second sub-pixels;

one end of the reinforcing structure surrounding any one of the first sub-pixels is connected with the first ohmic layer, and the other end of the reinforcing structure penetrates through the first passivation layer and is connected with the second ohmic layer.

9. The pixel cell of claim 1, further comprising a light screening layer disposed on a side of the display unit remote from the drive backplate.

10. The micro display screen, its characterized in that, micro display screen includes:

the micro display screen backboard comprises a driving circuit, an input interface and an output interface;

the display area is arranged on the micro display screen backboard, and comprises at least two display units which are arranged in an array mode and are included by the pixel units according to any one of claims 1 to 9;

and the peripheral common cathode is electrically connected with each display unit respectively.

11. A pixel level discrete device, characterized in that the pixel level discrete device comprises:

a discrete device backplate comprising at least two anode pads and at least one cathode pad;

the device main body is arranged on the discrete device backboard, and comprises at least two display units which are arranged in an array mode and are included in the pixel unit according to any one of claims 1 to 9.