A micro light-emitting diode display device

Abstract

The present invention provides a micro light-emitting diode display device. The LED array unit is formed on the surface of the substrate through cross trenches for isolation; the insulating layer covers all the LED array units and the trenches, and the insulating layer has notches exposing the surfaces of all the LED array units; the common electrode is disposed on the surface of the substrate around the LED array unit; the transparent conductive layer is deposited in the notches and extends to the surface of the insulating layer, and is directly or indirectly connected to the common electrode. Based on the above structure, after electrons are introduced through the common electrode, they are vertically injected into the first-type semiconductor layer through the transparent conductive layer, so that the current flowing through the LED array unit has no lateral spreading loss, thereby improving its light-emitting efficiency.

Description

Technical Field

[0001] The present invention relates to the field of light-emitting diodes, and in particular to a micro light-emitting diode display device. Background Art

[0002] Micro-component technology refers to an array of micro-sized components integrated at a high density on a substrate. At present, micro-pitch light-emitting diode technology has gradually become a research hotspot, and the industrial community expects high-quality micro-component products to enter the market. High-quality micro-pitch light-emitting diode products will have a profound impact on existing traditional display products such as LCD / OLEDs in the market.

[0003] In a light-emitting diode display, a first-type semiconductor layer serves as a common electrode between different micro light-emitting diodes. The first-type semiconductor layer is electrically connected to a corresponding electrode on a circuit substrate (such as a CMOS / TFT display substrate). The second-type semiconductor (such as the P pole) of each light-emitting diode is respectively electrically connected to the circuit substrate. However, the semiconductor has a high resistance value. Micro light-emitting diodes closer to the above-mentioned corresponding electrode will have more electron-hole pairs than those farther from the above-mentioned corresponding electrode. Because more electron-hole pairs recombine, the light-emitting brightness of micro light-emitting diodes closer to the above-mentioned corresponding electrode will be higher than that of micro light-emitting diodes farther from the above-mentioned corresponding electrode, resulting in uneven brightness of the micro light-emitting diode display.

[0004] In view of this, the inventor of the present invention specifically designed a micro light-emitting diode display device, and this case thus arises. Summary of the Invention

[0005] The purpose of the present invention is to provide a micro light-emitting diode display device to solve the problem of uneven brightness of micro light-emitting diode displays in the prior art.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] A micro light-emitting diode display device includes: a substrate, a plurality of LED array units, an insulating layer, a transparent conductive layer, and a common electrode;

[0008] Wherein, the LED array units are formed on the surface of the substrate through cross trenches for isolation; the insulating layer covers all the LED array units and trenches, and the insulating layer has a notch exposing the surface of each LED array unit; the common electrode is arranged on the surface of the substrate around the LED array units; the transparent conductive layer is deposited in the notch and extends to the surface of the insulating layer, and is directly or indirectly electrically connected to the common electrode;

[0009] The LED array unit at least includes a first metal bonding layer, a second-type semiconductor layer, an active region, and a first-type semiconductor layer stacked in sequence on the surface of the substrate.

[0010] Preferably, a filling layer is provided in each of the trenches, so that after the transparent conductive layer horizontally extends from the surface of the LED array unit to the filling layer, it is directly or indirectly electrically connected to the common electrode.

[0011] Preferably, the filling layer has the same horizontal height as the LED array unit.

[0012] Preferably, the transparent conductive layer covers each of the LED array units and the trenches and is electrically connected to the common electrode.

[0013] Preferably, a grid electrode interconnected with the common electrode is provided in the trench, and the transparent conductive layer is electrically connected to the grid electrode.

[0014] Preferably, a grid electrode interconnected with the common electrode is provided on the surface of the filling layer corresponding to the trench, and the transparent conductive layer is electrically connected to the grid electrode.

[0015] Preferably, the filling layer includes one or more stacks of polyimide, epoxy resin, silicon oxide, etc.

[0016] Preferably, the filling layer includes a conductive adhesive or a metal layer, and the common electrode forms electrical contact with the filling layer.

[0017] Preferably, the notch completely exposes the surface of the LED array unit.

[0018] Preferably, the common electrode is laminated on the short side edge of the substrate.

[0019] Preferably, the common electrode is disposed around the periphery of the LED array unit.

[0020] Preferably, the substrate includes a circuit substrate, which is integrally formed by polar-matching bonding with the common electrode and the first metal bonding layer through a metal bonding process respectively.

[0021] Preferably, the substrate includes a complementary metal oxide semiconductor substrate or a thin film transistor substrate.

[0022] Preferably, the grid electrode includes a metal reflection layer.

[0023] Preferably, the insulating layer includes one or more stacks of silicon oxide, silicon nitride, aluminum oxide, DBR reflection layer, etc.

[0024] As can be seen from the above technical solutions, the LED array unit is formed on the surface of the substrate through cross trenches for isolation; the insulating layer covers all the LED array units and the trenches, and the insulating layer has notches exposing the surfaces of the LED array units; the common electrode is disposed on the surface of the substrate around the LED array unit; the transparent conductive layer is deposited in the notches and extends to the surface of the insulating layer, directly or indirectly forming a connection with the common electrode. Based on the above structure, after electrons are introduced through the common electrode, they are vertically injected into the first-type semiconductor layer through the transparent conductive layer, so that the current flowing through the LED array unit has no lateral spreading loss, thereby improving its light extraction efficiency. At the same time, since the contact electrode of the first-type semiconductor layer is led out to the common electrode around the LED array unit through the transparent conductive layer, and the contact electrode of the second-type semiconductor layer is the first metal bonding layer; and the substrate is integrally formed by polar-matching bonding with the common electrode and the first metal bonding layer through a metal bonding process respectively; therefore, based on the above structure, there is no need to design contact electrodes with the same height, thereby reducing the manufacturing difficulty of the product.

[0025] Further, by providing a filling layer in each of the trenches, and the filling layer having the same horizontal height as the LED array unit; the transparent conductive layer horizontally extends from the surface of the LED array unit to the filling layer and directly or indirectly forms an electrical connection with the common electrode. This enables the transparent conductive layer or the grid electrode to be directly electrically connected to the common electrode without attaching to the sidewall of the LED array unit. Thus, the risk of breakage or short circuit that is likely to occur when the transparent conductive layer or the grid electrode is attached to the sidewall of the LED array unit is avoided; at the same time, through the provision of the filling layer, the connection routing position between the common electrode and the transparent conductive layer can be flexibly selected.

[0026] Secondly, by covering each of the LED array units and the trenches with the transparent conductive layer and forming an electrical connection with the common electrode, a transparent conductive layer for current spreading can be formed synchronously and the connection routing between the common electrode and the transparent conductive layer can be solved, reducing the number of process steps.

[0027] Thirdly, a grid electrode interconnected with the common electrode is provided in the trench or on the surface of the filling layer corresponding to the trench, and the transparent conductive layer forms an electrical connection with the grid electrode; further, the grid electrode includes a metal reflection layer, so that while ensuring the electrical interconnection between the common electrode and the transparent conductive layer, the grid electrode can also be used for metal reflection, avoiding light emission from the sidewalls, and thus improving the light extraction efficiency of the LED array unit.

[0028] Finally, by arranging the common electrode to surround the periphery of the LED array unit, the current passing through the common electrode can be introduced into each of the LED array units along the shortest path, avoiding current congestion. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the provided drawings.

[0030] Figure 1 It is a schematic structural diagram of the micro light-emitting diode display device provided in Embodiment 1 of the present invention;

[0031] Figure 2 It is a top view of the structure of the micro light-emitting diode display device provided in Embodiment 1 of the present invention;

[0032] Figure 3 It is another top view of the structure of the micro light-emitting diode display device provided in Embodiment 1 of the present invention;

[0033] Figure 4 It is a schematic structural diagram of the micro light-emitting diode display device provided in Embodiment 2 of the present invention;

[0034] Figure 5 It is a top view of the structure of the micro light-emitting diode display device provided in Embodiment 2 of the present invention;

[0035] Figure 6 It is another top view of the structure of the micro light-emitting diode display device provided in Embodiment 2 of the present invention;

[0036] Figure 7 It is a schematic structural diagram of the micro light-emitting diode display device provided in Embodiment 3 of the present invention;

[0037] Figure 8 It is a top view of the structure of the micro light-emitting diode display device provided in Embodiment 3 of the present invention;

[0038] Figure 9 It is another top view of the structure of the micro light-emitting diode display device provided in Embodiment 3 of the present invention;

[0039] Figure 10 It is a schematic structural diagram of the micro light-emitting diode display device provided in Embodiment 4 of the present invention;

[0040] Figure 11 It is a top view of the structure of the micro light-emitting diode display device provided in Embodiment 4 of the present invention;

[0041] Figure 12 It is another top view of the structure of the micro light-emitting diode display device provided in Embodiment 4 of the present invention;

[0042] Figure 13 Schematic structural diagram of the micro light-emitting diode display device provided in Embodiment 5 of the present invention;

[0043] Figure 14 Top view of the structure of the micro light-emitting diode display device provided in Embodiment 5 of the present invention;

[0044] Figure 15 Another top view of the structure of the micro light-emitting diode display device provided in Embodiment 5 of the present invention;

[0045] Symbol description in the figure: 201, 301, 401, 501, 601: First-type semiconductor layer; 202, 302, 402, 502, 602: Active region; 203, 303, 403, 503, 603: Second-type semiconductor layer; 204, 304, 404, 504, 604: Insulating layer; 205, 405, 505: Reflective layer; 206, 306, 406, 506, 606: Transparent conductive layer; 207, 307, 407, 507, 607: First metal bonding layer; 208, 308, 408, 508, 608: Common electrode; 209, 309, 409, 509, 609: Substrate; 210, 310, 410, 510, 610: LED array unit; 211, 311: Groove; 312, 512: Grille electrode, 413, 513, 613: Filling layer. Detailed implementation manners

[0046] To make the content of the present invention clearer, the content of the present invention will be further described below with reference to the accompanying drawings. The present invention is not limited to this specific embodiment. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0047] Embodiment 1

[0048] As Figure 1 shown, a micro light-emitting diode display device includes: a substrate 209, a plurality of LED array units 210, an insulating layer 204, a transparent conductive layer 206, and a common electrode 208;

[0049] Among them, the LED array unit 210 is formed on the surface of the substrate 209 through cross grooves 211 for isolation; the insulating layer 204 covers all the LED array units 210 and the grooves 211, and the insulating layer 204 has notches exposing the surfaces of the LED array units 210; the common electrode 208 is disposed on the surface of the substrate 209 outside the LED array unit 210; the transparent conductive layer 206 is deposited in the notches and extends to the surface of the insulating layer 204 to form an electrical connection with the common electrode 208;

[0050] The LED array unit 210 at least includes a first metal bonding layer 207, a second-type semiconductor layer 203, an active region 202, and a first-type semiconductor layer 201 that are sequentially stacked on the surface of the substrate 209.

[0051] It should be noted that the types of the first-type semiconductor layer 201, the active region 202, and the second-type semiconductor layer 203 in the micro-light-emitting element of this embodiment may also be unrestricted. For example, the first-type semiconductor layer 201 may be, but is not limited to, a gallium nitride layer. Correspondingly, the second-type semiconductor layer 203 may be, but is not limited to, a gallium nitride layer.

[0052] Optionally, the transparent conductive layer 206 covers each LED array unit 210 and the trench 211 and forms an electrical connection with the common electrode 208.

[0053] Optionally, the notch completely exposes the surface of the LED array unit 210.

[0054] Optionally, the substrate 209 includes a circuit substrate 209, which is integrally formed by a metal bonding process with the common electrode 208 and the first metal bonding layer 207 in a polarity-matching bonding manner.

[0055] Optionally, the substrate 209 includes a complementary metal oxide semiconductor substrate 209 or a thin film transistor substrate 209.

[0056] Optionally, the insulating layer 204 includes one or more stacks of silicon oxide, silicon nitride, aluminum oxide, and DBR reflection layers.

[0057] Optionally, a reflection layer 205 may also be provided on the surface of the insulating layer 204 corresponding to the sidewall of the LED array unit 210. The reflection layer 205 includes a metal reflection material and is used for metal reflection to avoid light emission from the sidewall, thereby improving the light extraction efficiency of the LED array unit 210.

[0058] Optionally, as Figure 2 shown, the common electrode 208 is stacked on the short side edge of the substrate 209. Or, as Figure 3 shown, the common electrode 208 is disposed around the periphery of the LED array unit 210.

[0059] As can be seen from the above technical solution, the LED array unit 210 is formed on the surface of the substrate 209 through cross grooves 211 for isolation; the insulating layer 204 covers all the LED array units 210 and the grooves 211, and the insulating layer 204 has notches exposing the surfaces of the LED array units 210; the common electrode 208 is disposed on the surface of the substrate 209 surrounding the LED array unit 210; the transparent conductive layer 206 is deposited on the notches and extends to the surface of the insulating layer 204 to form a connection with the common electrode 208. Based on the above structure, after electrons are introduced through the common electrode 208, they are vertically injected into the first-type semiconductor layer 201 through the transparent conductive layer 206, so that the current flowing through the LED array unit 210 has no lateral expansion loss, thereby improving its light extraction efficiency. At the same time, since the contact electrode of the first-type semiconductor layer 201 is led out to the common electrode 208 surrounding the LED array unit 210 through the transparent conductive layer 206, and the contact electrode of the second-type semiconductor layer 203 is the first metal bonding layer 207; and the substrate 209 is integrally formed by polar matching bonding with the common electrode 208 and the first metal bonding layer 207 through a metal bonding process respectively; therefore, based on the above structure, there is no need to design contact electrodes with the same height, thereby reducing the manufacturing process difficulty of the product.

[0060] Secondly, by covering each LED array unit 210 and the grooves 211 with the transparent conductive layer 206 to form an electrical connection with the common electrode 208, the transparent conductive layer 206 for current spreading can be synchronously formed and the connection trace between the common electrode 208 and the transparent conductive layer 206 can be solved, reducing the number of process steps.

[0061] Finally, by arranging the common electrode 208 to surround the LED array unit 210, the current passing through the common electrode 208 can be introduced into each LED array unit 210 along the shortest path, avoiding current congestion.

[0062] Embodiment 2

[0063] The application difference between this embodiment and Embodiment 1 is that in this embodiment, the transparent conductive layer only covers the top surface of the LED array unit, specifically as follows:

[0064] As Figure 4 shown, a micro light-emitting diode display device includes: a substrate 309, a plurality of LED array units 310, an insulating layer 304, a transparent conductive layer 306, and a common electrode 308;

[0065] Among them, the LED array units 310 are formed on the surface of the substrate 309 by being isolated through the cross grooves 311; the insulating layer 304 covers all the LED array units 310 and the grooves 311, and the insulating layer 304 has notches exposing the surfaces of the LED array units 310; the common electrode 308 is disposed on the surface of the substrate 309 around the LED array units 310; the transparent conductive layer 306 is deposited in the notches and extends to the surface of the insulating layer 304 to form an electrical connection with the common electrode 308.

[0066] The LED array units 310 at least include a first metal bonding layer 307, a second-type semiconductor layer 303, an active region 302, and a first-type semiconductor layer 301 that are sequentially stacked on the surface of the substrate 309.

[0067] It should be noted that the types of the first-type semiconductor layer 301, the active region 302, and the second-type semiconductor layer 303 in the micro light-emitting element of this embodiment may also not be limited. For example, the first-type semiconductor layer 301 may be, but is not limited to, a gallium nitride layer. Correspondingly, the second-type semiconductor layer 303 may be, but is not limited to, a gallium nitride layer.

[0068] Optionally, a grid electrode 312 interconnected with the common electrode 308 is provided in the grooves 311, and the transparent conductive layer 306 forms an electrical connection with the grid electrode 312.

[0069] Optionally, the grid electrode 312 includes a metal reflection layer.

[0070] Optionally, the notches completely expose the surfaces of the LED array units 310.

[0071] Optionally, the substrate 309 includes a circuit substrate 309, which is integrally formed by polar-matching bonding with the common electrode 308 and the first metal bonding layer 307 respectively through a metal bonding process.

[0072] Optionally, the substrate 309 includes a complementary metal oxide semiconductor substrate 309 or a thin film transistor substrate 309.

[0073] Optionally, the insulating layer 304 includes one or more stacks of silicon oxide, silicon nitride, aluminum oxide, and DBR reflection layers.

[0074] Optionally, as Figure 5 shown, the common electrode 308 is stacked on the short side edge of the substrate 309. Or, as Figure 6 shown, the common electrode 308 is disposed around the periphery of the LED array units 310.

[0075] As can be seen from the above technical solutions, the LED array units 310 are formed on the surface of the substrate 309 through cross trenches 311; the insulating layer 304 covers all the LED array units 310 and the trenches 311, and the insulating layer 304 has notches exposing the surfaces of the LED array units 310; the common electrode 308 is disposed on the surface of the substrate 309 surrounding the LED array units 310; the transparent conductive layer 306 is deposited in the notches and extends to the surface of the insulating layer 304 to form a connection with the common electrode 308. Based on the above structure, after electrons are introduced through the common electrode 308, they are vertically injected into the first-type semiconductor layer 301 through the transparent conductive layer 306, so that the current flowing through the LED array units 310 has no lateral spreading loss, thereby improving its light extraction efficiency. At the same time, since the contact electrode of the first-type semiconductor layer 301 is led out to the common electrode 308 outside the LED array units 310 through the transparent conductive layer 306, and the contact electrode of the second-type semiconductor layer 303 is the first metal bonding layer 307; and the substrate 309 is integrally formed by polar matching bonding with the common electrode 308 and the first metal bonding layer 307 through a metal bonding process respectively; therefore, based on the above structure, there is no need to design contact electrodes with the same height, thereby reducing the manufacturing difficulty of the product.

[0076] Again, a grid electrode 312 interconnected with the common electrode 308 is provided in the trench 311, and the transparent conductive layer 306 forms an electrical connection with the grid electrode 312; further, the grid electrode 312 includes a metal reflection layer, so that while ensuring the electrical interconnection between the common electrode 308 and the transparent conductive layer 306, the grid electrode 312 can also be used for metal reflection to avoid light extraction from the sidewalls, thereby improving the light extraction efficiency of the LED array units 310.

[0077] Finally, by surrounding the common electrode 308 around the periphery of the LED array units 310, the current passing through the common electrode 308 can be introduced into each LED array unit 310 along the shortest path, avoiding current congestion.

[0078] Embodiment 3

[0079] The application difference between this embodiment and Embodiment 1 is that a filling layer is provided at the trench in this embodiment, specifically as follows:

[0080] As Figure 7 shown, a micro light-emitting diode display device includes: a substrate 409, a plurality of LED array units 410, an insulating layer 404, a transparent conductive layer 406, and a common electrode 408;

[0081] Among them, the LED array unit 410 is formed on the surface of the substrate 409 through cross-groove isolation; the insulating layer 404 covers all the LED array units 410 and the grooves, and the insulating layer 404 has notches exposing the surfaces of the respective LED array units 410; the common electrode 408 is disposed on the surface of the substrate 409 surrounding the LED array unit 410; the transparent conductive layer 406 is deposited in the notches and extends to the surface of the insulating layer 404, and is directly electrically connected to the common electrode 408;

[0082] The LED array unit 410 at least includes a first metal bonding layer 407, a second-type semiconductor layer 403, an active region 402, and a first-type semiconductor layer 401 stacked in sequence on the surface of the substrate 409.

[0083] It should be noted that the types of the first-type semiconductor layer 401, the active region 402, and the second-type semiconductor layer 403 may also be unrestricted in the micro-light emitting element of this embodiment. For example, the first-type semiconductor layer 401 may be, but is not limited to, a gallium nitride layer. Correspondingly, the second-type semiconductor layer 403 may be, but is not limited to, a gallium nitride layer.

[0084] In this embodiment, a filling layer 413 is provided in each groove, so that after the transparent conductive layer 406 horizontally extends from the surface of the LED array unit 410 to the filling layer 413, it is directly electrically connected to the common electrode 408.

[0085] Optionally, the filling layer 413 has the same horizontal height as the LED array unit 410.

[0086] Optionally, the filling layer 413 includes one or more stacks of polyimide, epoxy resin, and silicon oxide.

[0087] Optionally, the notches completely expose the surfaces of the LED array units 410.

[0088] Optionally, as Figure 8 shown, the common electrode 408 is laminated on the short-side edge of the substrate 409; or as Figure 9 shown, the common electrode 408 is disposed around the periphery of the LED array unit 410.

[0089] Optionally, the substrate 409 includes a circuit substrate 409, which is integrally formed by polarity-matched bonding with the common electrode 408 and the first metal bonding layer 407 through a metal bonding process.

[0090] Optionally, the substrate 409 includes a complementary metal oxide semiconductor substrate 409 or a thin film transistor substrate 409.

[0091] Optionally, the insulating layer 404 includes one or more stacks of silicon oxide, silicon nitride, aluminum oxide, and DBR reflective layer.

[0092] Optionally, a reflective layer 405 may also be provided on the surface of the insulating layer corresponding to the side wall of the LED array unit 410. The reflective layer 405 includes a metal reflective material and is used for metal reflection to avoid light emission from the side wall, thereby improving the light extraction efficiency of the LED array unit 410.

[0093] As can be seen from the above technical solutions, the LED array unit 410 is formed on the surface of the substrate 409 by cross-groove isolation; the insulating layer 404 covers all the LED array units 410 and the grooves, and the insulating layer 404 has notches exposing the surfaces of the LED array units 410; the common electrode 408 is disposed on the surface of the substrate 409 outside the LED array unit 410; the transparent conductive layer 406 is deposited in the notches and extends to the surface of the insulating layer 404, directly or indirectly forming a connection with the common electrode 408. Based on the above structure, after electrons are introduced through the common electrode 408, they are vertically injected into the first-type semiconductor layer 401 through the transparent conductive layer 406, so that the current flowing through the LED array unit 410 has no lateral spreading loss, thereby improving its light extraction efficiency. At the same time, since the contact electrode of the first-type semiconductor layer 401 is led out to the common electrode 408 outside the LED array unit 410 through the transparent conductive layer 406, and the contact electrode of the second-type semiconductor layer 403 is the first metal bonding layer 407; and the substrate 409 is integrally formed by polar-matching bonding with the common electrode 408 and the first metal bonding layer 407 respectively through a metal bonding process; therefore, based on the above structure, there is no need to design contact electrodes with the same height, thereby reducing the manufacturing process difficulty of the product.

[0094] Furthermore, by providing a filling layer 413 in each groove, and the filling layer 413 has the same horizontal height as the LED array unit 410; after the transparent conductive layer 406 horizontally extends from the surface of the LED array unit 410 to the filling layer 413, it is directly or indirectly electrically connected to the common electrode 408. The transparent conductive layer 406 can be directly electrically connected to the common electrode 408 without adhering to the side wall of the LED array unit 410. Thus, when the transparent conductive layer 406 or the grid electrode adheres to the side wall of the LED array unit 410, the risk of breakage or short circuit is avoided; at the same time, through the setting of the filling layer 413, the connection routing position between the common electrode 408 and the transparent conductive layer 406 can be flexibly selected.

[0095] Secondly, by covering each LED array unit 410 and the filling layer 413 corresponding to the groove with the transparent conductive layer 406 and directly forming an electrical connection with the common electrode 408, a transparent conductive layer 406 for current spreading can be formed synchronously and the connection routing between the common electrode 408 and the transparent conductive layer 406 can be solved, reducing the number of process steps.

[0096] Finally, by arranging the common electrode 408 around the periphery of the LED array unit 410, the current passing through the common electrode 408 can be introduced into each LED array unit 410 along the shortest path, avoiding current congestion.

[0097] Embodiment 4

[0098] The difference in application between this embodiment and Embodiment 2 lies in that a filling layer 1 is provided at the trench, specifically as follows:

[0099] As Figure 10 shown, a micro light-emitting diode display device includes: a substrate 509, a plurality of LED array units 510, an insulating layer 504, a transparent conductive layer 506, and a common electrode 508;

[0100] Among them, the LED array units 510 are formed on the surface of the substrate 509 through cross trenches for isolation; the insulating layer 504 covers all the LED array units 510 and the trenches, and the insulating layer 504 has notches exposing the surfaces of the LED array units 510; the common electrode 508 is disposed on the surface of the substrate 509 outside the LED array units 510; the transparent conductive layer 506 is deposited in the notches and extends to the surface of the insulating layer 504, indirectly forming an electrical connection with the common electrode 508;

[0101] The LED array unit 510 at least includes a first metal bonding layer 507, a second-type semiconductor layer 503, an active region 502, and a first-type semiconductor layer 501 stacked in sequence on the surface of the substrate 509.

[0102] It should be noted that the types of the first-type semiconductor layer 501, the active region 502, and the second-type semiconductor layer 503 in the micro light-emitting element of this embodiment may also be unrestricted. For example, the first-type semiconductor layer 501 may be, but is not limited to, a gallium nitride layer. Correspondingly, the second-type semiconductor layer 503 may be, but is not limited to, a gallium nitride layer.

[0103] In this embodiment, a filling layer 513 is provided in each trench, so that the transparent conductive layer 506 horizontally extends from the surface of the LED array unit 510 to the filling layer 513; and a grid electrode 512 interconnected with the common electrode 508 is provided on the surface of the filling layer 513 corresponding to the trench, and the transparent conductive layer 506 forms an electrical connection with the grid electrode 512; thereby realizing the electrical interconnection between the transparent conductive layer 506 and the common electrode 508.

[0104] Optionally, the filling layer 513 has the same horizontal height as the LED array unit 510.

[0105] Optionally, the filling layer 513 includes one or more stacks of polyimide, epoxy resin, and silicon oxide.

[0106] Optionally, the notch completely exposes the surface of the LED array unit 510.

[0107] Optionally, as Figure 11 shown, the common electrode 508 is stacked on the short side edge of the substrate 509; or as Figure 12 shown, the common electrode 508 is disposed around the periphery of the LED array unit 510.

[0108] Optionally, the substrate 509 includes a circuit substrate 509, which is integrally formed by a polar-matching bonding process with the common electrode 508 and the first metal bonding layer 507 respectively through a metal bonding process.

[0109] Optionally, the substrate 509 includes a complementary metal oxide semiconductor substrate 509 or a thin film transistor substrate 509.

[0110] Optionally, the insulating layer 504 includes one or more stacks of silicon oxide, silicon nitride, aluminum oxide, and DBR reflective layer.

[0111] Optionally, a reflective layer 505 may also be provided on the surface of the insulating layer corresponding to the side wall of the LED array unit 510. The reflective layer 505 includes a metal reflective material and is used for metal reflection to avoid light emission from the side wall, thereby improving the light extraction efficiency of the LED array unit 510.

[0112] As can be seen from the above technical solutions, the LED array unit 510 is formed on the surface of the substrate 509 by cross-groove isolation; the insulating layer 504 covers all the LED array units 510 and the grooves, and the insulating layer 504 has a notch exposing the surface of each LED array unit 510; the common electrode 508 is disposed on the surface of the substrate 509 around the LED array unit 510; the transparent conductive layer 506 is deposited in the notch and extends to the surface of the insulating layer 504, directly or indirectly forming a connection with the common electrode 508. Based on the above structure, after electrons are introduced through the common electrode 508, they are vertically injected into the first-type semiconductor layer 501 through the transparent conductive layer 506, so that the current flowing through the LED array unit 510 has no lateral spreading loss, thereby improving its light extraction efficiency. At the same time, since the contact electrode of the first-type semiconductor layer 501 is led out to the common electrode 508 outside the LED array unit 510 through the transparent conductive layer 506, and the contact electrode of the second-type semiconductor layer 503 is the first metal bonding layer 507; and the substrate 509 is integrally formed by a polar-matching bonding process with the common electrode 508 and the first metal bonding layer 507 respectively through a metal bonding process; therefore, based on the above structure, there is no need to design contact electrodes with the same height, thereby reducing the manufacturing difficulty of the product.

[0113] Further, by providing a filling layer 513 in each groove, and the filling layer 513 has the same horizontal height as the LED array unit 510; the transparent conductive layer 506 extends horizontally from the surface of the LED array unit 510 to the filling layer 513 and then indirectly forms an electrical connection with the common electrode 508. This enables the grid electrode 512 to be directly electrically connected to the common electrode 508 without attaching to the side wall of the LED array unit 510. Thus, the risk of breakage or short circuit that is likely to occur when the grid electrode 512 is attached to the side wall of the LED array unit 510 is avoided; at the same time, through the setting of the filling layer 513, the connection routing position between the common electrode 508 and the transparent conductive layer 506 can be flexibly selected.

[0114] Again, a reflective layer 505 may also be provided on the surface of the insulating layer corresponding to the side wall of the LED array unit 510. The reflective layer 505 includes a metal reflective material and is used for metal reflection to avoid light emission from the side wall, thereby improving the light emission efficiency of the LED array unit 510.

[0115] Finally, by arranging the common electrode 508 around the periphery of the LED array unit 510, the current passing through the common electrode 508 can be introduced into each LED array unit 510 along the shortest path, avoiding current congestion.

[0116] Embodiment 5

[0117] It should be noted that the application difference between the filling layer in this embodiment and the filling layer in Embodiment 3 is that the filling layer in this embodiment is a conductive material, while the filling layer in Embodiment 3 is a non-conductive material; specifically as follows:

[0118] As Figure 13 shown, a micro light-emitting diode display device includes: a substrate 609, a plurality of LED array units 610, an insulating layer 604, a transparent conductive layer 606, and a common electrode 608;

[0119] Among them, the LED array units 610 are formed on the surface of the substrate 609 by cross grooves for isolation; the insulating layer 604 covers all the LED array units 610 and the grooves, and the insulating layer 604 has notches exposing the surfaces of the LED array units 610; the common electrode 608 is provided on the surface of the substrate 609 outside the LED array units 610; the transparent conductive layer 606 is deposited in the notches and extends to the surface of the insulating layer 604, indirectly forming an electrical connection with the common electrode 608;

[0120] The LED array unit 610 at least includes a first metal bonding layer 607, a second-type semiconductor layer 603, an active region 602, and a first-type semiconductor layer 601 stacked in sequence on the surface of the substrate 609.

[0121] It should be noted that the types of the first-type semiconductor layer 601, the active region 602, and the second-type semiconductor layer 603 in the micro-light-emitting element of this embodiment are not limited either. For example, the first-type semiconductor layer 601 can be, but is not limited to, a gallium nitride layer. Correspondingly, the second-type semiconductor layer 603 can be, but is not limited to, a gallium nitride layer.

[0122] In this embodiment, a filling layer 613 is provided in each trench, so that the transparent conductive layer 606 extends horizontally from the surface of the LED array unit 610 to the filling layer 613; optionally, the filling layer includes a conductive adhesive or a metal layer, and the common electrode forms an electrical contact with the filling layer; thereby realizing the electrical interconnection between the transparent conductive layer 606 and the common electrode 608.

[0123] Optionally, the filling layer 613 has the same horizontal height as the LED array unit 610.

[0124] Optionally, the notch completely exposes the surface of the LED array unit 610.

[0125] Optionally, as Figure 11 shown, the common electrode 608 is stacked on the short-side edge of the substrate 609; or as Figure 12 shown, the common electrode 608 is disposed around the periphery of the LED array unit 610.

[0126] Optionally, the substrate 609 includes a circuit substrate 609, which is integrally formed by polar-matching bonding with the common electrode 608 and the first metal bonding layer 607 through a metal bonding process.

[0127] Optionally, the substrate 609 includes a complementary metal oxide semiconductor substrate 609 or a thin film transistor substrate 609.

[0128] Optionally, the insulating layer 604 includes one or more stacks of silicon oxide, silicon nitride, aluminum oxide, and DBR reflection layers.

[0129] As can be seen from the above technical solutions, the LED array unit 610 is formed on the surface of the substrate 609 through cross trenches for isolation; the insulating layer 604 covers all the LED array units 610 and the trenches, and the insulating layer 604 has notches exposing the surfaces of the LED array units 610; the common electrode 608 is disposed on the surface of the substrate 609 surrounding the LED array unit 610; the transparent conductive layer 606 is deposited in the notches and extends to the surface of the insulating layer 604, and is directly or indirectly connected to the common electrode 608. Based on the above structure, after electrons are introduced through the common electrode 608, they are vertically injected into the first-type semiconductor layer 601 through the transparent conductive layer 606, so that the current flowing through the LED array unit 610 has no lateral spreading loss, thereby improving its light extraction efficiency. At the same time, since the contact electrode of the first-type semiconductor layer 601 is led out to the common electrode 608 outside the LED array unit 610 through the transparent conductive layer 606, and the contact electrode of the second-type semiconductor layer 603 is the first metal bonding layer 607; and the substrate 609 is integrally formed by polar-matching bonding with the common electrode 608 and the first metal bonding layer 607 respectively through a metal bonding process; therefore, based on the above structure, there is no need to design contact electrodes with the same height, thereby reducing the manufacturing difficulty of the product.

[0130] Further, a filling layer 613 is provided in each trench, so that the transparent conductive layer 606 horizontally extends from the surface of the LED array unit 610 to the filling layer 613; optionally, the filling layer includes a conductive adhesive or a metal layer, and the common electrode is in electrical contact with the filling layer; thereby realizing the electrical interconnection between the transparent conductive layer 606 and the common electrode 608. Thus, when the transparent conductive layer 606 or the metal electrode adheres to the side wall of the LED array unit 610, the risk of breakage or short circuit is avoided; at the same time, by selecting the filling layer 613 as a conductive adhesive or a metal layer, the connection trace between the additional common electrode 608 and the transparent conductive layer 606 can be avoided; the electrical interconnection between the common electrode 608 and the transparent conductive layer 606 is achieved in one step. Moreover, the conductive material of the filling layer 613 can also be used as a metal reflection to avoid light emission from the side wall, thereby improving the light extraction efficiency of the LED array unit 610.

[0131] Finally, by arranging the common electrode 608 to surround the periphery of the LED array unit 610, the current passing through the common electrode 608 can be introduced into each LED array unit 610 along the shortest path, avoiding current congestion.

[0132] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other.

[0133] It should also be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that an article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the article or device comprising the above elements.

[0134] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. A micro light-emitting diode display device, characterized in that, Comprising: a substrate, a plurality of LED array units, an insulating layer, a transparent conductive layer, and a common electrode; wherein, the LED array units are formed on the surface of the substrate through cross trenches for isolation; the insulating layer covers all the LED array units and the trenches, and the insulating layer has notches exposing the surfaces of all the LED array units; the common electrode is disposed on the surface of the substrate surrounding the LED array units; the transparent conductive layer is deposited in the notches and extends to the surface of the insulating layer, directly or indirectly forming an electrical connection with the common electrode; the LED array units at least include a first metal bonding layer, a second-type semiconductor layer, an active region, and a first-type semiconductor layer stacked in sequence on the surface of the substrate; wherein, the substrate includes a circuit substrate, which is integrally formed by polarity-matching bonding with the common electrode and the first metal bonding layer respectively; a filling layer is provided in each of the trenches, so that after the transparent conductive layer horizontally extends from the surface of the LED array units to the filling layer, it directly or indirectly forms an electrical connection with the common electrode; a grid electrode interconnected with the common electrode is provided in the trenches, and the transparent conductive layer forms an electrical connection with the grid electrode; 2. The micro light-emitting diode display device according to claim 1, wherein the filling layer has the same horizontal height as the LED array units; 3. The micro light-emitting diode display device according to claim 1, wherein the transparent conductive layer covers all the LED array units and the trenches, and forms an electrical connection with the common electrode; 4. The micro light-emitting diode display device according to claim 1, wherein a grid electrode interconnected with the common electrode is provided on the surface of the filling layer corresponding to the trenches, and the transparent conductive layer forms an electrical connection with the grid electrode; 5. The micro light-emitting diode display device according to claim 1, wherein the filling layer includes one or more stacks of polyimide, epoxy resin, silicon oxide, etc.; 6. The micro light-emitting diode display device according to claim 1, wherein the filling layer includes a conductive adhesive or a metal layer, and the common electrode forms electrical contact with the filling layer; 7. The micro light-emitting diode display device according to claim 1, characterized in that, the notches completely expose the surfaces of the LED array units; 8. The micro light-emitting diode display device according to claim 1, wherein the common electrode is laminated on the short-side edge of the substrate; 9. The micro light-emitting diode display device according to claim 1, wherein the common electrode is disposed surrounding the LED array units; 10. The micro light-emitting diode display device according to claim 1, wherein the circuit substrate is integrally formed by polarity-matching bonding with the common electrode and the first metal bonding layer respectively through a metal bonding process; 11. The micro light-emitting diode display device according to claim 1, wherein the substrate includes a complementary metal oxide semiconductor substrate or a thin film transistor substrate; 12. The micro light-emitting diode display device according to claim 1, wherein the grid electrode includes a metal reflection layer.

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