Micro display device

Abstract

The invention relates to a micro display device which comprises a driving back plate, and a first type of electrode contacts and a second type of electrode contacts which are opposite in polarity are arranged on the driving back plate. The pixel layer is stacked above the driving back plate, and sub-pixels are arranged in the pixel layer; the bottom end of each sub-pixel is electrically connected to the corresponding first type of electrode contact through a bottom conductive layer, and the top ends of the plurality of sub-pixels are electrically connected to the corresponding second type of electrode contact through a shared top conductive layer; corresponding light isolation assemblies are arranged on the peripheries of the sub-pixels, the light isolation assemblies are suspended above the bottom conducting layer, and the light isolation assemblies and the bottom conducting layer are insulated and isolated from each other; wherein a concave part is formed in the top conducting layer, and at least part of the concave part is located between the light isolation assemblies of every two adjacent sub-pixels. The pixel yield of the micro-display device can be remarkably improved, and the display brightness and the display contrast of the micro-display device can be improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to a microdisplay device. Background Technology

[0002] Microdisplay devices, characterized by their small size, high resolution, and high brightness, can be applied in numerous fields such as AR / VR devices, automotive displays, medical detection, and smart wearables. Micro-LED display technology, in particular, has seen widespread development in recent years due to its advantages of high efficiency, low power consumption, high density, and high stability. Microdisplay devices consist of pixel arrays, each containing several pixels (i.e., light-emitting units). The top and bottom ends of each pixel are opposite in polarity and need to be connected to a driving circuit on a driving backplane. The driving backplane then controls the pixel's light emission. The bottom end of the pixel is typically electrically connected to the driving backplane via a metal bonding layer. However, during the fabrication process, a metal fence of a certain height can easily form on top of the metal bonding layer. This metal fence can easily come into contact with the conductive layer at the top of the pixel, causing a short circuit and resulting in dead pixels, thus affecting the brightness and stability of the microdisplay device. Furthermore, crosstalk between pixels is prone to occur, affecting pixel brightness and display contrast, failing to meet usage requirements. Summary of the Invention

[0003] Therefore, the technical problem to be solved by the present invention is to reduce the dead lamp rate of micro-display devices, thereby improving pixel yield, display brightness and display contrast.

[0004] To address the aforementioned technical problems, the present invention provides a microdisplay device, comprising,

[0005] A drive backplate, wherein a first type of electrode contact and a second type of electrode contact with opposite polarities are provided on the drive backplate.

[0006] A pixel layer is stacked on top of the driving backplane, and sub-pixels are provided in the pixel layer; the bottom end of each sub-pixel is electrically connected to the corresponding first type of electrode contact through a bottom conductive layer, and the top ends of multiple sub-pixels are electrically connected to the corresponding second type of electrode contact through a common top conductive layer.

[0007] A light-isolating component is provided on the periphery of the sub-pixel. The light-isolating component is suspended above the bottom conductive layer and is mutually insulated from the bottom conductive layer.

[0008] The top conductive layer has a recessed portion, which is at least partially located between the light-isolating components of two adjacent sub-pixels.

[0009] In one embodiment of the present invention, the light-blocking component is made of metal or opaque non-metallic material.

[0010] In one embodiment of the present invention, the projections of the light-isolating components surrounding the sub-pixels on the driving backplate are all located inside the projection of the bottom conductive layer on the driving backplate.

[0011] In one embodiment of the present invention, the spacing between the sidewall of the sub-pixel and the peripheral light-blocking component is 5 to 800 nm.

[0012] In one embodiment of the present invention, a bottom ohmic contact layer is further provided between the bottom end of the sub-pixel and the bottom conductive layer, and the bottom end of the recess extends into the bottom ohmic contact layer between two adjacent sub-pixels and is insulated from the bottom ohmic contact layer.

[0013] In one embodiment of the present invention, the bottom end of the recess extends into the bottom conductive layer between two adjacent sub-pixels and is insulated from the bottom conductive layer.

[0014] In one embodiment of the present invention, an insulating gap is provided between the top surface of the bottom conductive layer of the sub-pixel and the bottom surface of the light-isolating component, the insulating gap being filled with an insulating medium, and the insulating gap being ≥5nm.

[0015] In one embodiment of the invention, the upper surface of the top conductive layer is in contact with the metal reinforcement, which is located within the cavity enclosed by the recess.

[0016] In one embodiment of the present invention, a lens is disposed on the upper part of the pixel layer, each lens covering at least one sub-pixel, and the bottom surface of each lens is in direct contact with the top surface of at least one metal reinforcement located on the upper surface of the top conductive layer; or, the bottom surface of each lens is higher than the top surface of at least one metal reinforcement located on the upper surface of the top conductive layer.

[0017] In one embodiment of the invention, the lower surface of the top conductive layer is in contact with a metal reinforcement, the metal reinforcement being located below the recess.

[0018] In one embodiment of the invention, the metal reinforcement portion is located between the bottom conductive layers of two adjacent sub-pixels and is insulated from and isolated from the bottom conductive layers.

[0019] In one embodiment of the invention, the metal reinforcement located on the lower surface of the top conductive layer is in direct contact with the corresponding second type of electrode contact.

[0020] In one embodiment of the invention, the bottom conductive layer of each sub-pixel is in contact with at least one of the first type of electrode contacts.

[0021] In one embodiment of the invention, the light blocking component includes at least one blocking element, all of which form a ring structure surrounding the periphery of the corresponding sub-pixel.

[0022] In one embodiment of the present invention, the top conductive layer and the top of the insulating member are in direct contact or are mutually insulated and isolated.

[0023] In one embodiment of the present invention, the thickness of the insulating element is 1 nm to 500 nm.

[0024] In one embodiment of the present invention, the sidewall of the sub-pixel is covered with a first insulating layer, and the sidewall of the sub-pixel and the surrounding light-blocking component are insulated and isolated by the first insulating layer.

[0025] In one embodiment of the present invention, a first bend is formed at the end of the recess away from the drive back plate. The first bend includes a first longitudinal portion and a first transverse portion. The included angle between the first longitudinal portion and the first transverse portion is not greater than 90°. The light blocking component is disposed below the first transverse portion.

[0026] In one embodiment of the present invention, the first lateral portion is in direct contact with or mutually insulated from the light-blocking component below it.

[0027] In one embodiment of the invention, the first longitudinal portion is in direct contact with or is insulated from the sidewall of the nearest sub-pixel.

[0028] In one embodiment of the invention, a second bend is formed at one end of the recess near the drive back plate. The second bend includes a second longitudinal portion and a second transverse portion. The included angle between the second longitudinal portion and the second transverse portion is not greater than 90°. The metal reinforcement is located at least partially above the second transverse portion.

[0029] In one embodiment of the invention, the sub-pixel is in contact with the top conductive layer only at its top tip; or, the top tip and at least part of the sidewalls of the sub-pixel are in contact with the top conductive layer.

[0030] In one embodiment of the present invention, the sub-pixel includes a first semiconductor layer, an active layer and a second semiconductor layer disposed sequentially in a direction away from the driving backplate. The edge of the first semiconductor layer extends outward beyond the active layer to form an extension. A light-blocking component surrounding the sub-pixel is suspended above the extension. The light-blocking component is mutually insulated from the first semiconductor layer.

[0031] In one embodiment of the present invention, the projection of the light-blocking component surrounding the sub-pixel on the driving backplane is located inside the projection of the first semiconductor layer on the driving backplane.

[0032] The technical solution of the present invention has the following advantages compared with the prior art:

[0033] The micro-display device of the present invention is provided with a light-isolating component, which is suspended above the bottom conductive layer and is insulated from the bottom conductive layer. This can effectively reduce the dead lamp rate of the micro-display device, improve its yield, and enhance the display brightness and contrast of the micro-display device, thereby enhancing the light efficiency. Attached Figure Description

[0034] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0035] Figure 1 This is a schematic diagram of the structure of the first embodiment of the micro-display device of the present invention;

[0036] Figure 2 yes Figure 1 A magnified view of a section at point M1;

[0037] Figure 3 This is a schematic diagram of the structure of a second embodiment of the microdisplay device of the present invention;

[0038] Figure 4 yes Figure 3 A magnified view of a section at point M2;

[0039] Figure 5 This is a schematic diagram of the third embodiment of the microdisplay device of the present invention;

[0040] Figure 6 yes Figure 5 A magnified view of a section at point M3;

[0041] Figure 7 This is a schematic diagram of the fourth embodiment of the microdisplay device of the present invention;

[0042] Figure 8This is a schematic diagram of the fifth embodiment of the microdisplay device of the present invention;

[0043] Figure 9 This is a schematic diagram of the sixth embodiment of the microdisplay device of the present invention;

[0044] Figure 10 This is a structural schematic diagram of the seventh embodiment of the microdisplay device of the present invention;

[0045] Figure 11 yes Figure 10 A magnified view of a section at point M4;

[0046] Figure 12 This is a partial schematic diagram of the structure of another example of the microdisplay device of the present invention;

[0047] Figure 13 This is a schematic diagram of the first embodiment of the micro-display device of the present invention when a lens is set;

[0048] Figure 14 This is a schematic diagram of a second embodiment of the microdisplay device of the present invention when a lens is disposed;

[0049] Figure 15 This is a schematic diagram of the third embodiment of the microdisplay device of the present invention when a lens is set;

[0050] Figure 16 yes Figure 15 A magnified view of a section at point M5;

[0051] Explanation of reference numerals in the instruction manual:

[0052] 10. Drive backplane; 101. Type I electrode contact; 102. Type II electrode contact;

[0053] 20. Pixel layer;

[0054] 30. Sub-pixel; 301. First semiconductor layer; 3011. Extension; 302. Active layer; 303. Second semiconductor layer;

[0055] 40. Bottom conductive layer;

[0056] 50. Top conductive layer; 501. Recessed portion; 5011. Cavity; 5012. First bent portion; 50121. First transverse portion; 50122. First longitudinal portion; 5013. Second bent portion; 50131. Second transverse portion; 50132. Second longitudinal portion;

[0057] 60. Light-blocking components; 601. Isolation elements;

[0058] 70. Bottom ohmic contact layer;

[0059] 80. Metal reinforcement components;

[0060] 90. First insulating layer; 100. Lens; Detailed Implementation

[0061] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present disclosure or its application or use.

[0062] In the description of this invention, it should be understood that the terms "vertical," "upper," "lower," "top," "side," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. 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 one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0063] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0064] Traditional microdisplay devices have pixel arrays, each containing several sub-pixels. The bottom of each sub-pixel is typically electrically connected to a driving backplane via a metal bonding layer. However, during fabrication, a metal fence of a certain height can easily form on top of the metal bonding layer. This metal fence can easily come into contact with the conductive layer at the top of the pixel, causing a short circuit and resulting in dead pixels, thus affecting the brightness and stability of the microdisplay device. Furthermore, crosstalk can easily occur between pixels, affecting pixel brightness and display contrast. Therefore, this application provides a microdisplay device to improve the above problems, thereby better ensuring the photoelectric performance and reliability of the LED display device, and improving display brightness and contrast.

[0065] The aforementioned sub-pixels are generally obtained by etching a compound semiconductor layer, which refers to a layer structure of a certain thickness prepared from a compound semiconductor material. Compound semiconductors typically refer to compounds formed from two or more elements, including crystalline inorganic compounds (such as III-V and II-VI compound semiconductors) and oxide semiconductors. The compound semiconductors involved in this application are mainly epitaxial materials for light-emitting diodes, such as InGaN ternary material systems or AlGaInP quaternary material systems, whose emission wavelengths can cover the entire spectrum from ultraviolet, visible, and infrared. Their substrate materials can be GaN, Si, SiC, Sapphire, GaAs, InP, etc.

[0066] Taking the Micro-LED field as an example, typical compound semiconductor materials mainly include P-type semiconductors, N-type semiconductors, and MQW active quantum wells sandwiched between the two. The MQW active quantum well serves as the active layer to emit light.

[0067] The structure of the microdisplay device of this application will be further described below with reference to the following specific embodiments.

[0068] Example 1

[0069] In this embodiment, the micro-display device has a Z-direction and an X-direction, which are perpendicular to each other. The Z-direction is the stacking direction of each layer of sub-pixels, that is, the up and down direction, which can also be understood as the direction away from / closer to the driving backplate. Here, "height" or "up and down" or "top and bottom" are all in the Z-direction.

[0070] In this embodiment, "bottom end of sub-pixel" refers to the end of the sub-pixel that is close to the driving backplane, and "top end of sub-pixel" refers to the end of the sub-pixel that is away from (away from) the driving backplane.

[0071] It should be noted that the cross-sectional views in the XZ plane in the accompanying drawings of this embodiment can be schematic diagrams after cutting a single cross section or schematic diagrams after cutting multiple cross sections together, so as to show the connection of different electrode contacts.

[0072] The microdisplay device (LED display device) in this embodiment includes a driving backplate 10 and a plurality of sub-pixels 30.

[0073] The driving backplate 10 is a component with a driving circuit. The first type of electrode contact 101 and the second type of electrode contact 102 are the lead-out terminals of the driving circuit, used to electrically connect the driving circuit and the sub-pixel 30. The sub-pixel 30 is a light-emitting element. Through the electrical connection between the driving backplate 10 and the sub-pixel 30, the connection between the sub-pixel and the driving circuit is realized, thereby driving the sub-pixel to emit light, so that each sub-pixel can be driven individually and emit light independently.

[0074] The aforementioned driving backplane 10 includes, but is not limited to, a CMOS (Complementary Metal Oxide Semiconductor) driving backplane 10.

[0075] The driving backplate 10 may be provided with a first type of electrode contact 101 and a second type of electrode contact 102. The polarities of the first type of electrode contact 101 and the second type of electrode contact 102 are opposite, with one being the anode and the other the cathode. Understandably, in order to prevent short circuits, the first type of electrode contact 101 and the second type of electrode contact 102 need to be insulated from each other. Through the provision of the first type of electrode contact 101 and the second type of electrode contact 102, the driving backplate 10 can be electrically connected to the sub-pixel 30, thereby controlling the light emission of each sub-pixel using the driving backplate.

[0076] Understandably, the two ends of sub-pixel 30 along the Z direction are the bottom and the top, respectively; the bottom and top of sub-pixel 30 are the two ends with opposite polarities. Sub-pixel 30 includes a P-type semiconductor layer, an active layer and an N-type semiconductor layer arranged sequentially along the Z direction. The active layer is used to emit light and can be an MQW active quantum well; the top of sub-pixel 30 is the end where the N-type semiconductor layer is located (or the end where the P-type semiconductor layer is located - anode), and the bottom is the end where the P-type semiconductor layer is located (or the end where the N-type semiconductor layer is located - cathode), which need to be connected to electrode contacts of different polarities respectively.

[0077] See Figures 1-2 This embodiment discloses a microdisplay device, including a driving backplane 10 and a pixel layer 20;

[0078] The drive backplate 10 is provided with a first type of electrode contact 101 and a second type of electrode contact 102 with opposite polarities;

[0079] The pixel layer 20 is stacked on top of the driving backplane 10, and sub-pixels 30 are provided in the pixel layer 20; the bottom end of each sub-pixel 30 is electrically connected to the corresponding first type electrode contact 101 through the bottom conductive layer 40, and the top ends of multiple sub-pixels 30 are electrically connected to the corresponding second type electrode contact 102 through a common top conductive layer 50 to form a top common electrode structure.

[0080] Each sub-pixel 30 has a corresponding light-isolating component 60 on its periphery. The light-isolating component 60 is suspended above the bottom conductive layer 40, and the light-isolating component 60 and the bottom conductive layer 40 are mutually insulated. It can be understood that the light-isolating component 60 can be located on the upper periphery, middle periphery or bottom periphery of the corresponding sub-pixel 30.

[0081] The top conductive layer 50 has a recessed portion 501, which is at least partially located between the light-blocking components 60 of two adjacent sub-pixels 30. That is, the recessed portion 501 of the top conductive layer 50 is located between two adjacent sub-pixels 30 and between the light-blocking components 60 surrounding the two adjacent sub-pixels 30.

[0082] In the above structure, the light-blocking component 60 surrounding each sub-pixel 30 can block the light emitted by the sub-pixel 30 towards the sidewall, causing this light to be reflected back or absorbed, thereby reducing light crosstalk between adjacent sub-pixels 30 and improving the display contrast of the micro-display device. In addition, the light-blocking component 60 is suspended above the bottom conductive layer 40, and the light-blocking component 60 and the bottom conductive layer 40 are mutually insulated and isolated from each other, which can prevent the light-blocking component 60 from directly contacting the bottom conductive layer 40. In this way, even if the light-blocking component 60 is made of conductive material and its top end is in contact with the top conductive layer 50, a short circuit will not occur between the top conductive layer 50 and the bottom conductive layer 40 due to the conductive connection of the light-blocking component 60. This effectively avoids the problem of dead pixels (sub-pixels cannot emit light normally) caused by the short circuit, and greatly reduces the dead pixel rate.

[0083] In some embodiments, the light-isolating component 60 uses a metal component. The reflective properties of the metal component reflect the light emitted by the sub-pixels toward the sidewalls, which not only reduces light crosstalk between sub-pixels but also improves the luminous efficiency and brightness of the sub-pixels. In addition, using a metal component can also increase the heat conduction capability of the device, maximizing the conduction of heat generated by the common electrode conductor due to resistance to the metal component for rapid heat dissipation, thereby reducing heat accumulation problems and greatly reducing the temperature of the display device, avoiding malfunctions caused by overheating.

[0084] For example, the aforementioned metal parts may be made of one or more of the following metal materials: Ti, Ni, Pt, Sn, Al, Ag, Rh, Au, etc.

[0085] Alternatively, in other solutions, the light-blocking component 60 may also be an opaque non-metallic component to block light emitted by the sub-pixel toward the sidewall.

[0086] In some implementations, for a sub-pixel 30 with a light-blocking component 60 on its periphery: the projection of the light-blocking component 60 on the driving backplate 10 of the sub-pixel 30 is a first projection, and the projection of the bottom conductive layer 40 of the sub-pixel 30 on the driving backplate 10 is a second projection. In this way, the first projection is located inside the second projection, which makes the light-blocking component 60 on the periphery of the sub-pixel 30 located directly above the bottom conductive layer 40.

[0087] In some implementations, such as Figure 2 As shown, for a sub-pixel 30 with an outer light-blocking component 60: the distance L3 between the sidewall of the sub-pixel 30 and the light-blocking component 60 surrounding the sidewall is 5 to 800 nm.

[0088] In some implementations, see Figures 1-2 A bottom ohmic contact layer 70 is also provided between the bottom end of the sub-pixel 30 and the bottom conductive layer 40. The bottom ohmic contact layer 70 is a conductive layer, and the bottom end of the sub-pixel 30 and the bottom conductive layer 40 are electrically connected through the bottom ohmic contact layer 70.

[0089] Furthermore, the peripheral light-blocking component 60 of the sub-pixel 30 is suspended above the bottom ohmic contact layer 70 at the bottom of the sub-pixel 30, and the light-blocking component 60 and the bottom ohmic contact layer 70 are mutually insulated and isolated.

[0090] In some schemes, the bottom end of the recess 501 of the top conductive layer 50 can extend into the bottom ohmic contact layer 70 between two adjacent sub-pixels 30, and the recess 501 and the outer bottom ohmic contact layer 70 are mutually insulated and isolated by an insulating medium to avoid short circuit.

[0091] Furthermore, the bottom end of the recess 501 extends into the bottom conductive layer 40 between two adjacent sub-pixels 30, and the recess 501 and the outer bottom conductive layer 40 are mutually insulated and isolated by an insulating medium to avoid short circuits.

[0092] Understandably, the bottom conductive layers 40 of two adjacent sub-pixels 30 need to be insulated from each other, and the recessed portion 501 of the top conductive layer 50 also needs to be insulated from the adjacent bottom conductive layer 40 to prevent short circuits. Figure 2 As shown, the recessed portion 501 and the adjacent peripheral bottom conductive layer 40 are insulated from each other by an insulating medium at point a1.

[0093] In some implementations, such as Figure 2 As shown, for the sub-pixel 30 with the light-isolating component 60 on the periphery: there is an insulating gap L1 between the top surface of the bottom conductive layer 40 of the sub-pixel 30 and the bottom surface of the light-isolating component 60. The insulating gap L1 is filled with an insulating medium. The insulating gap L1 is ≥ 5nm. The insulating gap should not be too small, otherwise it will be difficult to ensure the reliability of the insulation.

[0094] Understandably, in specific settings, if a bottom ohmic contact layer 70 is provided between the bottom end of the sub-pixel 30 and the bottom conductive layer 40, and the light blocking component 60 around the sub-pixel 30 is suspended above the bottom ohmic contact layer 70, then the aforementioned insulating gap is formed between the top surface of the bottom conductive layer 40 and the bottom surface of the light blocking component 60.

[0095] The bottom conductive layer 40 and the bottom ohmic contact layer 70 at the bottom of the sub-pixel 30 both extend outward beyond the bottom of the sub-pixel 30, and the light blocking component 60 is suspended above the extended area.

[0096] For example, the bottom ohmic contact layer 70 can be one or more of transparent conductive films such as indium tin oxide (ITO), indium zinc oxide (IZO), indium gallium tin oxide (IGZO), and aluminum-doped zinc oxide (AZO), or one or more of conductive metal materials such as nickel (Ni), chromium (Cr), gold (Au), silver (Ag), zinc (Zn), rhodium (Rh), beryllium (Be), and aluminum (Al), or a composite structure composed of transparent metal oxides and metals.

[0097] In some implementations, the bottom conductive layer 40 of each sub-pixel 30 contacts at least one first-type electrode contact 101 to achieve electrical connection. For example, see [link to relevant documentation]. Figure 1 Each sub-pixel 30 has its bottom conductive layer 40 in contact with only one type-1 electrode contact 101; or, see [link to relevant documentation]. Figure 7 Each sub-pixel 30 has a bottom conductive layer 40 that is in contact with two first-type electrode contacts 101 simultaneously.

[0098] In some embodiments, the light blocking component 60 includes at least one blocking member 601, and all the blocking members 601 in the light blocking component 60 form a ring structure surrounding the periphery of the corresponding sub-pixel 30 to better block the light emitted from the sub-pixel 30 toward the sidewall direction.

[0099] The aforementioned insulating member 601 can be a metal part or an opaque non-metal part.

[0100] For example, the light blocking component 60 has only one blocking member 601, which is ring-shaped and surrounds the periphery of the corresponding sub-pixel 30; or, the light blocking component 60 has multiple blocking members 601, which are circumferentially distributed around the periphery of the corresponding sub-pixel 30 to form a ring structure.

[0101] Furthermore, the top conductive layer 50 and the top of the insulating member 601 are in direct contact; or, see [reference needed]. Figure 4 The top conductive layer 50 and the top of the insulating member 601 are mutually insulated and isolated by the insulating medium at a3.

[0102] When the insulating member 601 is a metal part, even if the top conductive layer 50 and the top of the insulating member 601 are in direct contact, since the light blocking component 60 is suspended above the bottom conductive layer 40, the light blocking component 60 and the bottom conductive layer 40 are mutually insulated and isolated from each other, and a short circuit will not occur between the top conductive layer 50 and the bottom conductive layer 40 of the sub-pixel 30.

[0103] For sub-pixel 30 with the light-blocking component 60 on the periphery: See Figure 3 The top of the insulating member 601 in the light blocking component 60 can be lower than the top of the sub-pixel 30, or it can be flush with or higher than the top of the sub-pixel 30.

[0104] In some implementations, such as Figure 4 As shown, the thickness L2 of the insulating element 601 ranges from 1 nm to 500 nm to enhance its light-blocking effect. Furthermore, when the insulating element 601 is made of metal, this thickness range also further improves the heat dissipation of the device.

[0105] In some implementations, the sidewalls of the sub-pixel 30 are insulated from the peripheral light-blocking assembly 60; specifically, see [link to relevant documentation]. Figure 2 The sidewalls of subpixels 30 are all covered with a first insulating layer 90, and the sidewalls of subpixels 30 and the light-blocking components 60 on the periphery are insulated and isolated by the first insulating layer 90.

[0106] Among them, the bottom ohmic contact layer 70 and the bottom conductive layer 40 at the bottom of the sub-pixel 30 extend to the outside of the sub-pixel 30, and the upper surface and sidewalls of the extended area are also covered with an insulating medium, which can be made of the same material as the first insulating layer 90.

[0107] For example, see Figure 2In the sub-pixel 30 with a light-blocking component 60 on the periphery, one side of the light-blocking component 60 is insulated from the sidewall of the sub-pixel 30 (through the first insulating layer 90), the other side is insulated from the recess 501 of the top conductive layer 50, and the bottom end is insulated from the bottom conductive layer 40.

[0108] For example, the first insulating layer 90 may be made of one or more of the following materials: silicon oxide, aluminum oxide, silicon nitride, titanium oxide, hafnium oxide, tantalum oxide, niobium oxide, aluminum nitride, or gallium nitride; the material of the insulating medium may be the same as that of the first insulating layer 90.

[0109] In some embodiments, the bottom conductive layer 40 can be a metal bonding layer, which can be one or more of the following materials: nickel (Ni), tin (Sn), gold (Au), copper (Cu), aluminum (Al), indium tin oxide (ITO).

[0110] In some embodiments, the top conductive layer 50 is a transparent conductive layer to facilitate light transmission, allowing light emitted from the lower sub-pixel 30 to pass through the top conductive layer 50 and shine upwards. This transparent conductive layer can be one or more combinations of indium tin oxide (ITO), indium zinc oxide (IZO), aluminum-doped zinc oxide (AZO), Al-doped indium tin oxide, Ag-doped indium tin oxide, and Au-doped indium tin oxide.

[0111] In this invention, the sub-pixel 30 includes a first semiconductor layer 301, an active layer 302, and a second semiconductor layer 303 arranged sequentially along the direction away from the driving backplate (Z direction). The first semiconductor layer 301 is a P-type semiconductor layer, and the second semiconductor layer 303 is an N-type semiconductor layer.

[0112] In some ways, see Figures 10-12 In sub-pixel 30, the peripheral edge of the first semiconductor layer 301 extends outward beyond the active layer 302 to form an extension 3011. The light blocking component 60 of the periphery of sub-pixel 30 is suspended above the extension 3011, and the light blocking component 60 and the first semiconductor layer 301 are mutually insulated and isolated.

[0113] The above method ensures that the widths of the active layer 302 and the second semiconductor layer 303 in the X direction of the sub-pixel 30 are both smaller than the width of the first semiconductor layer 301 below in the X direction. This allows the first semiconductor layer 301 to extend outward, with the extension portion 3011 located below the peripheral light-isolating component 60. When the sub-pixel is fabricated in this way, the first semiconductor layer below the light-isolating component is not etched off. This allows the first semiconductor layer to block metal impurities generated by the ohmic contact layer or bonding layer below, thereby preventing the metal impurities from diffusing upward and causing short-circuit leakage between the first and second semiconductor layers in the sub-pixel.

[0114] In the above method, when etching the first semiconductor layer, the etching stop layer can be located entirely above the first semiconductor layer, or it can be etched to a partial depth of the first semiconductor layer, as long as the first semiconductor layer below the light-isolating component is not etched through. For example, such as... Figures 10-11 As shown, the light-isolating component 60 surrounding the sub-pixel 30 is completely suspended above the first semiconductor layer 301 of the sub-pixel. The light-isolating component 60 and the first semiconductor layer 301 are mutually insulated. In this way, during sub-pixel preparation, etching only needs to be performed above the first semiconductor layer 301, and the first semiconductor layer 301 is not etched at all; or, as... Figure 12 As shown, during sub-pixel preparation, the first semiconductor layer can be partially etched. For example, a portion of the first semiconductor layer below the light-isolating component 60 can be etched away to form a thinner extension 3011. At this time, the upper surface of the first semiconductor layer 301 has two planes i1 and i2 with different heights. The height of plane i1 is lower than the height of plane i2. The light-isolating component 60 is located above plane i1, and the outer peripheral edge of plane i2 is flush with the outer peripheral edge of the active layer 302.

[0115] Furthermore, the projections of the light-blocking components 60 surrounding the sub-pixel 30 onto the driving backplate 10 are all located inside the projection of the first semiconductor layer 301 of the sub-pixel onto the driving backplate 10.

[0116] Alternatively, in some embodiments, the light-blocking component 60 surrounding the sub-pixel 30 is suspended above the bottom conductive layer 40 of the sub-pixel, and the light-blocking component 60 surrounding the sub-pixel is located outside the first semiconductor layer 301 of the sub-pixel. In this embodiment, the first semiconductor layer can be completely etched away during preparation, down to below the first semiconductor layer.

[0117] Example 2

[0118] The main difference between this embodiment and Embodiment 1 is that the top conductive layer 50 is electrically connected to a metal reinforcement 80 to enhance the current spreading capability and increase the current intensity.

[0119] The metal reinforcement 80 can be arranged in the following ways:

[0120] First layout: See reference Figures 1-2 The upper surface of the top conductive layer 50 is in contact with the metal reinforcement 80, which is located within the cavity 5011 enclosed by the recess 501.

[0121] The shape of the metal reinforcement 80 is adapted to the shape of the recess 501.

[0122] Further, see Figures 13-16 A lens 100 is provided on the upper part of the pixel layer 20, each of which covers at least one sub-pixel 30, so that the lens 100 and the sub-pixel 30 correspond one-to-one, or one lens 100 covers multiple sub-pixels 30.

[0123] The bottom surface of each lens 100 is in direct contact with the top surface of at least one metal reinforcement 80 located on the upper surface of the top conductive layer 50.

[0124] Alternatively, the bottom surface of each lens 100 is higher than the top surface of at least one metal reinforcement 80 located on the upper surface of the top conductive layer 50.

[0125] For example, taking a one-to-one correspondence between each lens 100 and sub-pixel 30, that is, one lens 100 covers only one sub-pixel 30, a metal reinforcement 80 is provided between each two adjacent sub-pixels 30, see reference. Figure 14 The bottom surface g1 of lens 100 and the top surface g2 of metal reinforcement 80 are in direct contact; or, see [reference needed]. Figure 13 , Figure 15 and Figure 16 The bottom surface g1 of the lens 100 is higher than the top surface g2 of the metal reinforcement 80.

[0126] Second layout: See below Figure 8 The lower surface of the top conductive layer 50 is in contact with the metal reinforcement 80, which is located below the recess 501.

[0127] Furthermore, the metal reinforcement 80 extends into the bottom conductive layer 40 between adjacent sub-pixels 30, and the metal reinforcement 80 is insulated from the surrounding bottom conductive layer 40 to avoid short circuits.

[0128] In some implementation schemes, see Figure 9 The metal reinforcement 80 on the lower surface of the top conductive layer 50 is in direct contact with the corresponding second type of electrode contact 102.

[0129] Example 3

[0130] See Figures 1-6 The main difference between this embodiment and Embodiment 1 is that a first bent portion 5012 is formed at the end of the recessed portion 501 of the top conductive layer 50 away from the drive back plate 10.

[0131] The first bending portion 5012 includes a first longitudinal portion 50122 and a first transverse portion 50121. The included angle θ1 between the first longitudinal portion 50122 and the first transverse portion 50121 is not greater than 90°. A light blocking component 60 is provided below the first transverse portion 50121.

[0132] For example, see Figure 2 and Figure 4 In the first bend, the included angle θ1 between the first longitudinal portion 50122 and the first transverse portion 50121 is 90°, or, see [reference] Figure 6 The first transverse portion 50121 is inclined upward, so that the included angle θ1 between the first longitudinal portion 50122 and the first transverse portion 50121 in the first bending portion is less than 90°.

[0133] In some embodiments, the first lateral portion 50121 is in direct contact with the light-blocking component 60 below; or, see [reference needed]. Figure 4 and Figure 6 The first horizontal portion 50121 and the light-blocking component 60 below are mutually insulated and isolated by the insulating medium at point a3.

[0134] In some embodiments, the first vertical portion 50122 is in direct contact with the sidewall of the nearest sub-pixel 30; or, see [reference needed]. Figure 4 and Figure 6 The first vertical portion 50122 and the sidewall of the nearest sub-pixel 30 are mutually insulated and isolated by an insulating medium at a2.

[0135] In some implementations, see Figure 2 A second bend 5013 is formed at one end of the recessed portion 501 near the drive back plate 10. The second bend 5013 includes a second longitudinal portion 50132 and a second transverse portion 50131. The included angle θ2 between the second longitudinal portion 50132 and the second transverse portion 50131 is not greater than 90°.

[0136] The second bend 5013 in the recess 501 is located below the first bend 5012.

[0137] When the upper surface of the top conductive layer 50 contacts the metal reinforcement 80, and the metal reinforcement 80 is located within the cavity 5011 enclosed by the recess 501, the portion of the metal reinforcement 80 within the cavity 5011 is located above the second transverse portion 50131. For example, see [reference needed]. Figure 2A portion of the metal reinforcement 80 is located above the second transverse portion 50131, and another portion extends below the second transverse portion 50131.

[0138] Example 4

[0139] In this embodiment, the electrical connection between the top of the sub-pixel 30 and the top conductive layer 50 can be in the following forms:

[0140] First method: Refer to Figure 13 The sub-pixel 30 only contacts the top conductive layer 50 at its tip. This allows the sub-pixel 30 to expose part or all of its tip, enabling the exposed area to contact the top conductive layer 50 and achieve a top electrical connection.

[0141] The second method: Refer to Figures 1-2 The top edge and at least part of the sidewalls of sub-pixel 30 are in contact with the top conductive layer 50. For example... Figure 2 As shown, the top j1 and part of the sidewall j2 of the sub-pixel 30 are exposed, so that the exposed area comes into contact with the top conductive layer 50 to achieve top electrical connection. This method can further increase the electrical contact area and improve the current expansion capability.

[0142] Example 5

[0143] See Figures 13-16 In this embodiment, a lens 100 is provided on the upper part of the pixel layer 20. Each lens 100 covers at least one sub-pixel 30, that is, the lens 100 and the sub-pixel 30 can correspond one-to-one, or one lens 100 can cover multiple sub-pixels 30.

[0144] In some configurations, two adjacent lenses 100 can be separated from each other and set independently, or they can be in contact with each other and connected together.

[0145] Understandably, all lenses 100 are located on the outside of the upper surface of the top conductive layer 50.

[0146] Furthermore, to better ensure the focusing and collimating function of the lens 100, the bottom surface of the lens 100 can be lower than the top surface of the sub-pixel 30 it covers.

[0147] The micro-display device described in the above embodiment, by setting up a suspended light isolation component, can reduce light crosstalk between adjacent sub-pixels, improve the display contrast of the micro-display device, and effectively avoid the dead pixel problem caused by the short circuit phenomenon, greatly reducing the dead pixel rate and improving the reliability and service life of the micro-display device.

[0148] All the above-mentioned optional technical solutions can be combined in any way to form optional embodiments of the present invention. That is, any number of embodiments can be combined to meet the needs of different application scenarios. All of these are within the protection scope of this application and will not be described in detail here.

[0149] It should be noted that the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A microdisplay device, characterized in that: include, A drive backplate, wherein a first type of electrode contact and a second type of electrode contact with opposite polarities are provided on the drive backplate. A pixel layer is stacked on top of the driving backplane, and sub-pixels are provided in the pixel layer; the bottom end of each sub-pixel is electrically connected to the corresponding first type of electrode contact through a bottom conductive layer, and the top ends of multiple sub-pixels are electrically connected to the corresponding second type of electrode contact through a common top conductive layer. A light-isolating component is provided on the periphery of the sub-pixel. The light-isolating component is suspended above the bottom conductive layer and is mutually insulated from the bottom conductive layer. The top conductive layer has a recessed portion, which is at least partially located between the light-isolating components of two adjacent sub-pixels.

2. The microdisplay device according to claim 1, characterized in that: The light-blocking component is made of metal or opaque non-metallic material.

3. The microdisplay device according to claim 1, characterized in that: The projections of the light-isolating components surrounding the sub-pixels on the driving backplate are all located inside the projection of the bottom conductive layer on the driving backplate.

4. The microdisplay device according to claim 3, characterized in that: The spacing between the sidewall of the sub-pixel and the surrounding light-blocking component is 5–800 nm.

5. The microdisplay device according to claim 1, characterized in that: A bottom ohmic contact layer is also provided between the bottom end of the sub-pixel and the bottom conductive layer. The bottom end of the recess extends into the bottom ohmic contact layer between two adjacent sub-pixels and is insulated from the bottom ohmic contact layer.

6. The microdisplay device according to claim 5, characterized in that: The bottom end of the recess extends into the bottom conductive layer between two adjacent sub-pixels and is insulated from the bottom conductive layer.

7. The microdisplay device according to claim 1, characterized in that: An insulating gap exists between the top surface of the bottom conductive layer of the sub-pixel and the bottom surface of the light-isolating component, the insulating gap being filled with an insulating medium, and the insulating gap being ≥5nm.

8. The microdisplay device according to claim 1, characterized in that: The upper surface of the top conductive layer is in contact with the metal reinforcement, which is located within the cavity enclosed by the recess.

9. The microdisplay device according to claim 8, characterized in that: A lens is provided on the upper part of the pixel layer, each lens covering at least one sub-pixel, and the bottom surface of each lens is in direct contact with the top surface of at least one metal reinforcement located on the upper surface of the top conductive layer; or, the bottom surface of each lens is higher than the top surface of at least one metal reinforcement located on the upper surface of the top conductive layer.

10. The microdisplay device according to claim 1, characterized in that: The lower surface of the top conductive layer is in contact with the metal reinforcement, which is located below the recess.

11. The microdisplay device according to claim 10, characterized in that: The metal reinforcement portion is located between the bottom conductive layers of two adjacent sub-pixels and is insulated from and isolated from the bottom conductive layers.

12. The microdisplay device according to claim 10, characterized in that: The metal reinforcement located on the lower surface of the top conductive layer is in direct contact with the corresponding second type of electrode contact.

13. The microdisplay device according to claim 1, characterized in that: The bottom conductive layer of each sub-pixel is in contact with at least one of the first type of electrode contacts.

14. The microdisplay device according to claim 1, characterized in that: The light blocking component includes at least one blocking element, and all the blocking elements in the light blocking component form a ring structure surrounding the periphery of the corresponding sub-pixel.

15. The microdisplay device according to claim 14, characterized in that: The top conductive layer and the top of the insulating member are either in direct contact or mutually insulated.

16. The microdisplay device according to claim 14, characterized in that: The thickness of the insulating element is 1 nm to 500 nm.

17. The microdisplay device according to claim 1, characterized in that: The sidewall of the sub-pixel is covered with a first insulating layer, and the sidewall of the sub-pixel and the surrounding light-blocking component are insulated and isolated by the first insulating layer.

18. The microdisplay device according to claim 1, characterized in that: A first bend is formed at the end of the recess away from the drive back plate. The first bend includes a first longitudinal portion and a first transverse portion. The included angle between the first longitudinal portion and the first transverse portion is not greater than 90°. The light blocking component is disposed below the first transverse portion.

19. The microdisplay device according to claim 18, characterized in that: The first lateral portion is in direct contact with or is mutually insulated from the light-blocking component below it.

20. The microdisplay device according to claim 18, characterized in that: The first longitudinal portion is in direct contact with or is insulated from the sidewall of the nearest sub-pixel.

21. The microdisplay device according to claim 8, characterized in that: A second bend is formed at one end of the recess near the drive back plate. The second bend includes a second longitudinal portion and a second transverse portion. The included angle between the second longitudinal portion and the second transverse portion is not greater than 90°. The metal reinforcement is located at least partially above the second transverse portion.

22. The microdisplay device according to claim 1, characterized in that: The sub-pixel is in contact with the top conductive layer only at its top tip; or, the top tip and at least part of the sidewalls of the sub-pixel are in contact with the top conductive layer.

23. The microdisplay device according to claim 1, characterized in that: The sub-pixel includes a first semiconductor layer, an active layer, and a second semiconductor layer arranged sequentially in a direction away from the driving backplate. The edge of the first semiconductor layer extends outward beyond the active layer to form an extension. A light-blocking component surrounding the sub-pixel is suspended above the extension. The light-blocking component is mutually insulated from the first semiconductor layer.

24. The microdisplay device according to claim 23, characterized in that: The projection of the light-isolating component surrounding the sub-pixel on the driving backplane is located inside the projection of the first semiconductor layer on the driving backplane.

Images