CN117352625B - Micro LED micro display chip and preparation method - Google Patents

Abstract

This application discloses a MicroLED microdisplay chip and a preparation method, which includes: a driving panel, including a plurality of first contacts; a first luminescent layer, located on the driving panel, including a plurality of first LED units; a second luminescent layer, Above the first light-emitting layer, a plurality of second LED units arranged in an array are included; the orthographic projections of the first LED unit and the second LED unit on the driving panel do not overlap; the first LED unit and at least one adjacent third LED unit are The two LED units are both connected to corresponding first contacts; the first LED unit and the second LED unit can be driven independently by the driving panel through time sharing. This application uses different LED units to emit light of different colors to achieve full-color display. Different LED units are located on different layers and can share the first contact, reducing contact resistance. The structure is more integrated, reduces power consumption, and improves the stability of full-color lighting. properties, different LED units do not overlap, improving the luminous brightness.

Description

MicroLED microdisplay chip and preparation method

Technical field

This application belongs to the field of micro-display technology, and specifically relates to a MicroLED micro-display chip and a preparation method.

Background technique

Microdisplay MicroLED, also known as micro light-emitting diode, refers to a high-density integrated LED array, which is realized through LED miniaturization and matrixing. Compared with traditional LED displays, MicroLED has many advantages in terms of die, packaging, integration process, backplane, driver and other processes. All are different. In MicroLED, each LED pixel unit can emit light by itself. Since a higher number of integrations can be achieved on a chip of the same area, the photoelectric conversion efficiency of MicroLED is greatly improved and high-resolution and high-brightness display designs can be realized.

Full-color microdisplays have a wide range of important application values, especially near-eye displays, including AR, VR, etc. However, the technology to achieve full-color microdisplays still has a lot of room for improvement. In particular, when the LED pixel units used to emit different colors of light in current full-color MicroLED display chips are stacked, there is a large overlap of the three primary colors of RGB, resulting in low luminous efficiency. Moreover, the LED pixel units need to be prepared in a certain order, making the preparation difficult. .

Contents of the invention

Object of the invention: The object of the present invention is to provide a micro light-emitting diode, which protects the reflective layer and reduces the contact resistivity by setting a barrier layer; another object of the present invention is to provide a method for preparing the above-mentioned micro light-emitting diode.

Technical solution: In order to achieve the above-mentioned object of the invention, the present invention provides a MicroLED microdisplay chip, including:

A driving panel, the driving panel includes a plurality of first contacts;

At least two light-emitting layers, the at least two light-emitting layers include a first light-emitting layer and a second light-emitting layer;

The first light-emitting layer is provided on the driving panel; the first light-emitting layer includes a plurality of first LED units, the first LED units are arranged on the driving panel, and the first LED units are To emit light of the first color;

The second light-emitting layer is disposed above the first light-emitting layer, the second light-emitting layer includes a plurality of second LED units arranged in an array, and the second LED units are used to emit light of a second color;

Wherein, the orthographic projections of the first LED unit and the second LED unit on the driving panel do not overlap; the second doped semiconductor layer of the first LED unit and the adjacent at least one third The second doped semiconductor layers of the two LED units are electrically connected to the corresponding first contacts; the first LED unit and the second LED unit can be individually controlled by the driving panel through time sharing. drive.

In some embodiments, it also includes:

The at least two light-emitting layers further include a third light-emitting layer, and the third light-emitting layer is provided above the second light-emitting layer; the third light-emitting layer includes a plurality of third LED units arranged in an array, and the third light-emitting layer A three-LED unit is used to emit a third color of light;

Wherein, the orthographic projection of any one of the third LED unit, the first LED unit and the second LED unit on the driving panel does not overlap; the second doping of the third LED unit The doped semiconductor layer, the second doped semiconductor layer of at least one adjacent first LED unit, and the second doped semiconductor layer of at least one adjacent second LED unit are all in contact with the corresponding third doped semiconductor layer. A contact is electrically connected; the third LED unit can be driven individually by the driving panel through time sharing.

In some embodiments, it also includes:

A first planarization layer is located between the first light-emitting layer and the second light-emitting layer; the first planarization layer transmits the first color light;

A second planarization layer is located between the second light-emitting layer and the third light-emitting layer; the second planarization layer transmits both the first color light and the second color light; a plurality of The third LED unit is arranged on the second planarization layer;

A third planarization layer is provided on the third light-emitting layer; the third planarization layer transmits the first color light, the second color light, and the third color light.

In some embodiments, it also includes:

A first bonding layer is located between the driving panel and the first LED unit; the driving panel also includes a first common contact, and the first doped semiconductor layer of the first LED unit is connected to the corresponding The first common contact connection;

A second bonding layer is located between the first planarization layer and the second LED unit; the driving panel also includes a second common contact, the first doped semiconductor layer of the second LED unit (201) Connected to the corresponding second public contact;

A third bonding layer is located between the second planarization layer and the third LED unit; the driving panel also includes a third common contact, the first doped semiconductor layer of the third LED unit Connect with the corresponding third public contact.

In some embodiments, it is characterized by:

The second bonding layer has a first opening exposing the first LED unit at a position corresponding to the first LED unit, and part of the second light-emitting layer fills the first opening;

The third bonding layer has a second opening exposing the first LED unit at a position corresponding to the first LED unit; the third bonding layer has a second opening exposing the second LED unit at a position corresponding to the second LED unit. The third opening of the second LED unit; part of the third light-emitting layer fills the second opening and the third opening.

In some embodiments,

The first planarization layer has a plurality of first through holes, the plurality of first through holes are respectively arranged around the first LED unit, and the first color light is emitted through the first through holes;

The second planarization layer has a plurality of second through holes, the plurality of second through holes are respectively arranged around the second LED unit, and the second color light is emitted through the second through holes;

The third planarization layer has a plurality of third through holes, the plurality of third through holes are respectively arranged around the third LED unit, and the third color light is emitted through the third through holes;

The second planarization layer also has a plurality of fourth through holes, the fourth through holes are arranged relative to the first through holes; the third planarization layer also has a plurality of fifth through holes, the The fifth through hole is arranged relative to the fourth through hole; the first through hole, the fourth through hole and the fifth through hole are connected in sequence and form a first through hole with the first LED unit. sunken areas;

The third planarization layer also has a plurality of sixth through holes, the sixth through holes are arranged relative to the second through holes; the sixth through holes are connected to the second through holes and are connected to the second through holes. A second recessed area is formed between the second LED units;

A third recessed area is formed between the third through hole and the third LED unit.

In some embodiments, the aperture of the first through hole, the fourth through hole and the fifth through hole is smaller than the aperture of at least one of the first opening and the second opening; The diameters of the second through hole and the sixth through hole are smaller than the diameter of the third opening.

In some embodiments, it also includes:

A leveling layer, the leveling layer includes a first leveling unit, a second leveling unit and a third leveling unit; the first leveling unit fills the first depressed area, and the second leveling unit The second recessed area is filled, and the third filling unit fills the third recessed area.

In some embodiments, it also includes:

A reflective layer, the reflective layer is provided on the sidewall of any one of the first recessed area, the second recessed area, and the third recessed area; or

The reflective layer is provided on the sidewall of at least one of the first through hole, the second through hole, the third through hole, the fourth through hole, the fifth through hole, and the sixth through hole.

In some embodiments, it also includes:

A microlens array includes a plurality of microlens units, and the microlens units are disposed above at least one of the first LED unit and the second LED unit.

In some embodiments, further, the microlens unit is disposed on the third planarization layer and covers at least one of the first recessed area, the second recessed area, and the third recessed area. By.

In some embodiments, the first light-emitting layer further includes a first passivation layer and a first electrode layer; the first passivation layer covers the first LED unit, and the first passivation layer has a function to expose the first a first opening of the second doped semiconductor layer of an LED unit; the first electrode layer connects the corresponding second doped semiconductor layer of the first LED unit with the corresponding said first opening; The first contact is electrically connected;

The second luminescent layer further includes a second passivation layer and a second electrode layer, the second passivation layer covers the second LED unit, and the second passivation layer has a second passivation layer exposing the second LED unit. a second opening of the doped semiconductor layer; the second electrode layer electrically connects the corresponding second doped semiconductor layer of the second LED unit to the corresponding first contact through the second opening; connect;

The third luminescent layer further includes a third passivation layer and a third electrode layer, the third passivation layer covers the third LED unit, and the third passivation layer has a second layer exposing the third LED unit. The third opening of the doped semiconductor layer; the third electrode layer electrically connects the corresponding second doped semiconductor layer of the third LED unit to the corresponding first contact through the three openings .

In some embodiments, the first light-emitting layer further includes a first protective layer covering the first passivation layer and the first electrode layer;

The second luminescent layer further includes a second protective layer covering the second passivation layer and the second electrode layer;

The third luminescent layer further includes a third protective layer covering the third passivation layer and the third electrode layer.

In some embodiments, it also includes:

A plurality of conductive posts, the conductive posts are provided on the corresponding first contacts and connected with the corresponding first contacts;

The conductive pillars collectively connect the corresponding first electrode layer, the corresponding second electrode layer, and the corresponding third electrode layer.

In some embodiments, the conductive pillars sequentially penetrate the first passivation layer, the first protective layer, the first planarization layer, and the second passivation layer in a direction away from the driving panel. , the second protective layer, the second planarization layer, and the third passivation layer to simultaneously connect the first electrode layer, the second electrode layer, and the third electrode layer.

In some embodiments, at least one first LED unit, at least one second LED unit and at least one third LED unit form a full-color pixel unit of the MicroLED microdisplay chip.

In some embodiments, the size of the first LED unit, the second LED unit, and the third LED unit is 0.1 to 10 microns; the adjacent first LED unit, the second LED unit The distance between the third LED units is 1 to 10 microns.

In some embodiments, this application also provides a method for preparing a MicroLED microdisplay chip, including:

providing a driving panel, the driving panel including a plurality of first contacts;

A first light-emitting layer is formed on the driving panel. The first light-emitting layer includes a plurality of first LED units. The first LED units are arranged on the driving panel. The first LED units are used to emit light. first color light;

A second light-emitting layer is formed above the first light-emitting layer, the second light-emitting layer includes a plurality of second LED units arranged in an array, the second LED units are used to emit light of a second color;

Wherein, the orthographic projections of the first LED unit and the second LED unit on the driving panel do not overlap; the second doped semiconductor layer of the first LED unit and the adjacent at least one third The second doped semiconductor layer of the two LED units is electrically connected to the driving panel through the first contact; the first LED unit and the second LED unit can respectively be time-shared by the driving panel. Driven alone.

In some embodiments, the method further includes:

A third light-emitting layer is formed above the second light-emitting layer, the third light-emitting layer includes a plurality of third LED units arranged in an array, the third LED units are used to emit light of a third color;

Wherein, the orthographic projection of any one of the third LED unit, the first LED unit and the second LED unit on the driving panel does not overlap; the second doping of the third LED unit The doped semiconductor layer, the second doped semiconductor layer of at least one adjacent first LED unit, and the second doped semiconductor layer of at least one adjacent second LED unit are all in contact with the corresponding third doped semiconductor layer. A contact is electrically connected; the third LED unit can be driven individually by the driving panel through time sharing.

In some embodiments,

Before forming the second light-emitting layer above the first light-emitting layer, forming a first planarization layer on the first light-emitting layer, the first planarization layer transmitting the first color light;

Before forming a third light-emitting layer above the second light-emitting layer, a second planarization layer is formed on the second light-emitting layer, and the second planarization layer makes the first color light, the second light-emitting layer All colors of light are transmitted;

After forming a third light-emitting layer above the second light-emitting layer, a third planarization layer is formed on the third light-emitting layer. The third planarization layer causes the first color light and the second light-emitting layer to Both color light and the third color light are transmitted.

In some embodiments, it also includes:

The driving panel and the first LED unit are bonded through a first bonding layer; the driving panel also includes a first common contact, and the first doped semiconductor layer of the first LED unit is connected to the corresponding The first common contact connection;

The first planarization layer and the second LED unit are bonded through a second bonding layer; the driving panel also includes a second common contact, and the first doped semiconductor layer of the second LED unit Connect with the corresponding second public contact;

The second planarization layer and the third LED unit are bonded through a third bonding layer; the driving panel also includes a third common contact, and the first doped semiconductor layer of the third LED unit Connect with the corresponding third public contact.

In some embodiments, a plurality of first through holes are formed on the first planarization layer, the plurality of first through holes are respectively arranged around the first LED unit, and the first color light passes through the The first through hole exits;

A plurality of second through holes and a plurality of fourth through holes are formed on the second planarization layer. The plurality of second through holes are respectively arranged around the second LED unit, and the second color light passes through the second through holes. The second through hole exits, and the fourth through hole is arranged relative to the first through hole;

A plurality of third through holes, a plurality of fifth through holes and a plurality of sixth through holes are formed on the third planarization layer, and the plurality of third through holes are respectively arranged around the third LED unit, so The third color light is emitted through the third through hole, the fifth through hole is arranged relative to the fourth through hole, and the sixth through hole is arranged relative to the second through hole;

The first through hole, the fourth through hole and the fifth through hole are connected in sequence and form a first recessed area with the first LED unit;

The sixth through hole communicates with the second through hole, and forms a second recessed area between the sixth through hole and the second LED unit;

A third recessed area is formed between the third through hole and the third LED unit;

The method further includes: forming a leveling layer; the leveling layer includes a first leveling unit, a second leveling unit and a third leveling unit; the first leveling unit fills the first recessed area, The second filling unit fills the second recessed area, and the third filling unit fills the third recessed area.

In some embodiments, before forming the leveling layer, the method further includes:

A reflective layer is formed on the side wall of any one of the first recessed area, the second recessed area, and the third recessed area; or

A reflective layer is formed on a side wall of at least one of the first through hole, the second through hole, the third through hole, the fourth through hole, the fifth through hole, and the sixth through hole.

In some embodiments, after forming the leveling layer, the method further includes:

Forming a microlens array, the microlens array includes a plurality of microlens units, the microlens units are disposed above at least one of the first LED unit, the second LED unit, and the third LED unit. .

In some embodiments,

The step of forming the first light-emitting layer on the driving panel further includes: forming a plurality of the first LED units, a first passivation layer, and a first electrode layer, the first passivation layer covering the first LED unit and the first bonding layer, the first passivation layer has a first opening exposing the second doped semiconductor layer of the first LED unit, the first electrode layer passes through the first opening The second doped semiconductor layer of the first LED unit is electrically connected to the corresponding first contact;

The step of forming a second light-emitting layer on the first planarization layer further includes: forming a plurality of the second LED units, a first and second passivation layer, and a second electrode layer, the second passivation layer covering The second LED unit and the second bonding layer, the second passivation layer has a second opening exposing the second doped semiconductor layer of the second LED unit, the second electrode layer passes through the The second opening electrically connects the second doped semiconductor layer of the second LED unit to the corresponding first contact;

The step of forming a third light-emitting layer on the second planarization layer further includes: forming a plurality of the third LED units, a third passivation layer, and a third electrode layer, the third passivation layer covering the The third LED unit and the third bonding layer, the third passivation layer has a third opening exposing the second doped semiconductor layer of the third LED unit, the third electrode layer passes through the three openings The second doped semiconductor layer of the third LED unit is electrically connected to the corresponding first contact.

In some embodiments, forming a plurality of the first LED units includes:

A first substrate is provided, and a first LED epitaxial layer is provided on the first substrate. The first LED epitaxial layer includes a stacked first doped semiconductor layer, an active layer, and a second doped semiconductor layer;

Bonding and connecting the driving panel and the first LED epitaxial layer through a first bonding layer;

removing the first substrate and exposing the second doped semiconductor layer of the first LED epitaxial layer;

Etching the first LED epitaxial layer according to the MESA pattern designed by the patterned mask to form a plurality of the first LED units;

The step of forming a plurality of second LED units includes:

A second substrate is provided, and a second LED epitaxial layer is provided on the second substrate. The second LED epitaxial layer includes a stacked first doped semiconductor layer, an active layer, and a second doped semiconductor. layer;

Bonding and connecting the first planarization layer and the second LED epitaxial layer through the second bonding layer;

removing the second substrate and exposing the second doped semiconductor layer of the second LED epitaxial layer;

Etching the second LED epitaxial layer according to the MESA pattern designed by the patterned mask to form a plurality of second LED units;

The step of forming a plurality of third LED units includes:

A third substrate is provided, and a third LED epitaxial layer is provided on the third substrate. The third LED epitaxial layer includes a stacked first doped semiconductor layer, an active layer, and a second doped semiconductor. layer;

Bonding and connecting the second planarization layer and the third LED epitaxial layer through the third bonding layer;

removing the third substrate and exposing the second doped semiconductor layer of the third LED epitaxial layer;

The third LED epitaxial layer is etched according to the MESA pattern designed by the patterned mask to form a plurality of third LED units.

In some embodiments, the first doped semiconductor layer and the second doped semiconductor layer may include IIVI materials such as ZnSe or ZnO or IIIV nitride materials such as GaN, AlN, InN, InGaN, GaP, AlInGaP, One or more layers of AlGaAs and its alloys.

In some embodiments, the first doped semiconductor layer is a p-type semiconductor layer, and the second doped semiconductor layer is an n-type semiconductor layer.

In some embodiments, an active layer is further provided between the first doped semiconductor layer and the second doped semiconductor layer. The active layer may be a multi-quantum well structure for confining electrons and hole carriers. In the quantum well region, when electrons and holes recombine, the carriers will emit photons after radiative recombination, converting electrical energy into light energy.

Beneficial effects: Compared with the existing technology, the MicroLED microdisplay chip of the present application includes: a driving panel including a plurality of first contacts; at least two luminescent layers, and the at least two luminescent layers include a first luminescent layer; the second light-emitting layer; the first light-emitting layer is provided on the driving panel; the first light-emitting layer includes a plurality of first LED units, the first LED units are arranged on the driving panel, and the first LED units are used to emit light of the first color; The second light-emitting layer is disposed above the first light-emitting layer. The second light-emitting layer includes a plurality of second LED units arranged in an array. The second LED units are used to emit light of the second color; wherein, the first LED unit and the second light-emitting layer The orthographic projections of the LED units on the driving panel do not overlap; the second doped semiconductor layer of the first LED unit and the second doped semiconductor layer of at least one adjacent second LED unit are both in contact with the corresponding first contact Electrically connected; the first LED unit and the second LED unit can be driven independently by the driving panel through time sharing. The MicroLED microdisplay chip of this application emits light of different colors through different LED units to achieve full-color display. Different LED units are located on different layers and can share the first contact, reducing contact resistance. The structure is more integrated and reduces Power consumption improves the stability of full-color luminescence. In addition, different LED units do not overlap, which improves luminous brightness. In addition, the through holes on the planarization layer surround any LED unit of the corresponding different layers, which can prevent any LED unit from overlapping. The side walls leak light and improve the light extraction efficiency.

A method of preparing a MicroLED microdisplay chip of the present application includes: providing a driving panel, which includes a plurality of first contacts; forming a first luminescent layer on the driving panel, and the first luminescent layer includes a plurality of first LED units. , the first LED unit is arranged on the driving panel, and the first LED unit is used to emit light of the first color; a second luminescent layer is formed above the first luminescent layer, and the second luminescent layer includes a plurality of second luminescent elements arranged in an array. LED unit, the second LED unit is used to emit the second color light; wherein, the orthographic projections of the first LED unit and the second LED unit on the driving panel do not overlap; the second doped semiconductor layer of the first LED unit and the phase The second doped semiconductor layer of at least one adjacent second LED unit is electrically connected to the driving panel through the first contact; the first LED unit and the second LED unit can be independently driven by the driving panel through time sharing. This preparation method does not need to distinguish the production order when preparing multiple layers of LED units for emitting light of different colors, and can be freely sequenced, simplifying the preparation difficulty; and each layer of LED units emits light independently, and the LED units are surrounded by through holes on the planarization layer. This method forms an independent and penetrating reflective structure on the planarization layer, thereby improving the light extraction efficiency of different LED units.

Description of the drawings

The technical solutions and other beneficial effects of the present invention will become apparent through a detailed description of specific embodiments of the present invention below in conjunction with the accompanying drawings.

Figure 1 shows a top view of the MicroLED microdisplay chip of the present application;

Figure 2 shows a schematic cross-sectional view of D-D’ in Figure 1;

Figure 3 shows a top view of the full-color pixel unit of the present application;

Figure 4 shows a schematic cross-sectional view of A-A' in Figure 3;

Figure 5 shows a schematic cross-sectional view of B-B' in Figure 3;

Figure 6 shows a schematic cross-sectional view of C-C' in Figure 3;

Figure 7 shows a schematic structural diagram of forming the first LED epitaxial layer on the driving panel in this application;

Figure 8 shows a schematic structural diagram of forming the first LED unit in this application;

Figure 9 shows a schematic structural diagram of forming the first passivation layer, the first electrode layer and the first protective layer in this application;

Figure 10 shows a schematic structural diagram of forming the first planarization layer in this application;

Figure 11 shows a schematic structural diagram of forming a reflective layer on the side wall of the first through hole in this application;

Figure 12 shows a schematic structural diagram of forming the first filling unit in this application;

Figure 13 shows a schematic structural diagram of forming the second LED epitaxial layer in this application;

Figure 14 shows a schematic structural diagram of forming a second LED unit in this application;

Figure 15 shows a schematic structural diagram of forming the second passivation layer, the second electrode layer and the second protective layer in this application;

Figure 16 shows a schematic structural diagram of forming the second planarization layer in this application;

Figure 17 shows a schematic structural diagram of forming a second filling unit in this application;

Figure 18 shows a schematic structural diagram of forming the third LED unit and the third planarization layer in this application;

Figure 19 shows a schematic cross-sectional view of a MicroLED microdisplay chip of another structure;

Figure 20 shows a schematic structural diagram of forming the first LED epitaxial layer on the driving panel in a method of preparing a MicroLED microdisplay chip with another structure;

Figure 21 shows a schematic diagram of forming the first LED unit in a method for preparing a MicroLED microdisplay chip with another structure;

Figure 22 shows a schematic diagram of forming the first light-emitting layer in a method for preparing a MicroLED microdisplay chip with another structure;

Figure 23 shows a schematic diagram of forming the first planarization layer in a method for preparing a MicroLED microdisplay chip with another structure;

Figure 24 shows a schematic diagram of forming a second light-emitting layer in a method for preparing a MicroLED microdisplay chip with another structure;

Figure 25 shows a schematic diagram of forming a second planarization layer in a method for preparing a MicroLED microdisplay chip with another structure;

Figure 26 shows a schematic diagram of forming a third light-emitting layer in a method of preparing a MicroLED microdisplay chip with another structure;

Figure 27 shows a schematic diagram of forming a third planarization layer in a method for preparing a MicroLED microdisplay chip with another structure;

Reference signs: 1-first opening, 2-first light-emitting layer, 3-second opening, 4-second light-emitting layer, 5-third opening, 6-third light-emitting layer, 10-driving panel , 11-first LED epitaxial layer, 12-second LED epitaxial layer, 13-third LED epitaxial layer, 20-first LED unit, 30-first planarization layer, 40-second LED unit, 50-th Second planarization layer, 60-third LED unit, 70-third planarization layer, 80-planarization layer, 90-reflective layer, 101-first contact, 21-first passivation layer, 22-first Electrode layer, 23-first protective layer, 41-second passivation layer, 42-second electrode layer, 43-second protective layer, 61-third passivation layer, 62-third electrode layer, 63-th Three protective layers, 100-first bonding layer, 200-second bonding layer, 300-third bonding layer, 400-first recessed area, 500-second recessed area, 600-third recessed area, 700 -Microlens array, 800-microlens unit, 900-conductive pillar, 201-first doped semiconductor layer, 202-second doped semiconductor layer, 203-active layer, 210-first opening, 301- First through hole, 410-second opening, 501-second through hole, 502-fourth through hole, 610-third opening, 701-third through hole, 702-fifth through hole, 703-sixth through hole hole, 801 - first filling unit, 802 - second filling unit, 803 - third filling unit.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts fall within the scope of protection of the present invention.

The disclosure of the present invention provides many different embodiments or examples for implementing various structures of the present invention. In order to simplify the disclosure of the present invention, the components and arrangements of specific examples are described herein. Of course, they are merely examples and are not intended to limit the invention. Furthermore, the present invention may repeat reference numbers and/or reference letters in different examples, such repetition being for purposes of simplicity and clarity and does not itself indicate a relationship between the various embodiments and/or arrangements discussed. In addition, the present invention provides examples of various specific processes and materials, but one of ordinary skill in the art will recognize the application of other processes and/or the use of other materials.

In general, the terms may be understood, at least in part, in light of the above usage of the present invention. For example, the term "one or more" as used herein may be used to describe any component, structure or feature in the singular, or may be used to describe any component, structure or feature in the plural, depending at least in part on this disclosure. combination. Similarly, terms such as "a," "an," or "the" may also be understood to convey a singular usage or to convey a plural usage, depending at least in part on the invention. Additionally, the term "based on" may be understood as not necessarily intended to convey an exclusive set of factors, but rather that the invention may instead, at least in part, permit the presence of additional factors that do not necessarily have to be explicitly recited.

It should be readily understood that the meanings of "on", "on" and "on" in the present invention should be interpreted in the broadest manner, so that "on" does not only mean "directly on something" "on", but also means "on something" including the presence of intermediate parts or layers between the two, and "on something" or "on something" not only means "on top of something" ” or “on something,” but also includes the meaning of “on something” or “on something” without an intermediate part or layer between the two.

In addition, for convenience of description, spatially relative terms such as “below”, “under”, “lower”, “on”, “upper”, etc. may be used in the present invention to describe an element or component and The relationship of another element or component shown in the drawings. In addition to the orientation depicted in the figures, spatially relative terms are intended to encompass different orientations of the device in use or operation. The device may be otherwise oriented, rotated 90° or at other orientations and the spatially relative descriptors used herein interpreted accordingly.

The term "layer" as used in the present invention refers to a portion of material that includes a region having a certain thickness. A layer may extend throughout the entire underlying or superstructure, or may have an extent that is less than the extent of the underlying or superstructure. Furthermore, a layer may be a region of a homogeneous or inhomogeneous continuous structure, the thickness of which is less than the thickness of the continuous structure. For example, a layer may be located between the top and bottom surfaces of a continuous structure or between any pair of horizontal planes therebetween. The layers may extend horizontally, vertically and/or along tapered surfaces. The substrate may be a layer, may include one or more layers therein, and/or may have one or more layers on, above, and/or below it. A layer can include multiple layers. For example, the semiconductor layers may include one or more doped or undoped semiconductor layers and may be of the same or different materials.

MicroLED displays have many advantages such as self-illumination, high efficiency, low power consumption, high integration, and high stability. They are also small in size, highly flexible, and easy to disassemble and merge. They can be applied to any existing display from small to large sizes. display application. MicroLED, also known as micro light-emitting diode, is generally several hundred microns in size. With the emergence of MicroLED microdisplay technology, display devices such as augmented reality (AR) display devices, virtual reality (VR) display devices, near-eye displays (NED) and head-up displays, Miniaturization and high resolution of HUD) equipment are possible. In these application scenarios, the size of Micro LED is usually 0.1-10 microns.

In some embodiments, the term drive panel 10 as used in this application refers to a material on which subsequent layers of material are added. The drive panel 10 itself can be patterned. The material added to the top of drive panel 10 may be patterned or may remain unpatterned. The driving panel 10 may be, for example but not limited to, a display substrate including a silicon-based CMOS driving plate or a thin film field effect transistor driving plate, such as a CMOS (Complementary Metal Oxide Semiconductor, complementary metal oxide semiconductor) backplane or a TFT glass substrate.

Embodiments of the present disclosure describe a full-color MicroLED microdisplay chip and a method for manufacturing the MicroLED microdisplay chip. In order to manufacture a full-color MicroLED microdisplay chip, multiple sub-pixels with different emitting colors (such as red, green, and blue) are integrally formed into a full-color pixel. Sub-pixel micro-LEDs are individually driven by one or more drive circuits to emit the primary colors of the corresponding color scale respectively, and the human eye can see the full color gamut of full-color pixels composed of multiple sub-pixels.

In order to integrally form multiple sub-pixel LEDs or micro-LEDs emitting different colors (eg, three primary colors) on the same driving panel, a stacked structure of light-emitting diode units is disclosed, and the light-emitting diode unit includes a substantially flat top surface. Implement stacking structure. Each layer of the MicroLED microdisplay chip can independently emit different colors.

Referring to Figures 1 and 19, a MicroLED microdisplay chip is provided, including: a driving panel 10 that includes a plurality of first contacts 101; at least two luminescent layers, and the at least two luminescent layers include the first luminescent layer 2 and the second light-emitting layer 4; the first light-emitting layer 2 is provided on the driving panel 10; the first light-emitting layer 2 includes a plurality of first LED units 20, the first LED units 20 are arranged on the driving panel 10, and the first LED The unit 20 is used to emit light of the first color; the second light-emitting layer 4 is provided above the first light-emitting layer 2. The second light-emitting layer 4 includes a plurality of second LED units 40 arranged in an array. The second LED unit 40 is used to Emit second color light; wherein, the orthographic projections of the first LED unit 20 and the second LED unit 40 on the driving panel 10 do not overlap; the second doped semiconductor layer 202 of the first LED unit 20 and at least one adjacent The second doped semiconductor layer 202 of the second LED unit 40 is electrically connected to the corresponding first contact 101; the first LED unit 20 and the second LED unit 40 can be driven individually by the driving panel 10 through time sharing. .

In some embodiments, further referring to FIG. 19 , at least two light-emitting layers further include a third light-emitting layer 6 disposed above the second light-emitting layer 4 ; the third light-emitting layer 6 includes a plurality of third LED units arranged in an array. 60. The third LED unit 60 is used to emit the third color light; wherein, the orthographic projection of the third LED unit 60 and any one of the first LED unit 20 and the second LED unit 40 on the driving panel 10 does not overlap; The second doped semiconductor layer 202 of the third LED unit 60 , the second doped semiconductor layer 202 of the adjacent at least one first LED unit 20 , the second doped layer of the adjacent at least one second LED unit 40 The semiconductor layers 202 are electrically connected to the corresponding first contacts 101; the third LED unit 60 can be driven individually by the driving panel 10 through time sharing.

It can be understood that the first luminescent layer 2, the second luminescent layer 4, and the third luminescent layer 6 are stacked.

In some embodiments, further referring to Figure 19, the MicroLED microdisplay chip also includes: a first planarization layer 30, located between the first luminescent layer 2 and the second luminescent layer 4; the first planarization layer 30 makes the first Color light is transmitted through; the second planarization layer 50 is located between the second luminescent layer 4 and the third luminescent layer 6; the second planarization layer 50 transmits both the first color light and the second color light; a plurality of The three LED units 60 are arranged on the second planarization layer 50; the third planarization layer 70 is provided on the third light-emitting layer 6; the third planarization layer 70 uses the first color light, the second color light, and the third color light. All colors of light are transmitted through.

In some embodiments, in the MicroLED microdisplay chip provided in Figure 19, different LED units emit light of different colors to achieve full-color display. Different LED units are located in different layer structures and can share the first contact 101, reducing The contact resistance of the LED units between different layer structures improves the stability of full-color luminescence. The flattening layer can directly transmit the light emitted by the LED, achieving large-area light extraction.

In some embodiments, the first planarization layer 30 , the second planarization layer 50 , and the third planarization layer 70 can be made of transparent materials to achieve the transmission of the first color light, the second color light, and the third color light.

In some embodiments, further referring to FIGS. 1 and 2 , yet another MicroLED microdisplay chip is provided, including: a driving panel 10 , a plurality of first LED units 20 , a first planarization layer 30 , and a plurality of second LEDs. unit 40 and the second planarization layer 50; the driving panel 10 includes a plurality of first contacts 101; a plurality of first LED units 20 are arranged on the driving panel 10, and the first LED unit 20 is used to emit the first color light; The first planarization layer 30 has a plurality of first through holes 301. The plurality of first through holes 301 are respectively arranged around the first LED unit 20, and the first color light is emitted through the first through holes 301; a plurality of second LED units 40 Arranged on the first planarization layer 30, the second LED unit 40 is used to emit the second color light; the second planarization layer 50 has a plurality of second through holes 501, and the plurality of second through holes 501 respectively surround the second The LED unit 40 is configured so that the second color light emits through the second through hole 501; wherein, the orthographic projections of the first LED unit 20 and the second LED unit 40 on the driving panel 10 do not overlap; the second doped color of the first LED unit 20 does not overlap. The hybrid semiconductor layer 202 and the second doped semiconductor layer 202 of at least one adjacent second LED unit 40 are electrically connected to the corresponding first contacts 101; the first LED unit 20 and the second LED unit 40 are respectively It can be driven individually by time sharing by the driving panel 10 . It can be understood that the MicroLED microdisplay chip of this embodiment emits light of different colors through different LED units to achieve full-color display. Different LED units are located in different layers and can share the first contact 101, which reduces the number of LED units in different layers. Contact resistance improves the stability of full-color lighting. The first through hole 301 and the second through hole 302 surround any LED unit of the corresponding different layers, which can prevent the side wall of any LED unit from leaking light and improve the light extraction efficiency.

In some embodiments, further referring to FIGS. 1 and 2 , the MicroLED microdisplay chip further includes: a plurality of third LED units 60 and a third planarization layer 70 ; the third LED units 60 are arranged in the second planarization layer 50 On the top, the third LED unit 60 is used to emit third color light; the third planarization layer 70 has a plurality of third through holes 701, and the plurality of third through holes 701 are respectively arranged around the third LED unit 60, and the third color light Emit through the third through hole 701; wherein, the orthographic projection of the third LED unit 60 and any of the first LED unit 20 and the second LED unit 40 on the driving panel 10 does not overlap; the third LED unit 60 and the corresponding Any one of the adjacent first LED unit 20 and the second LED unit 40 is electrically connected to the driving panel 10 through the first contact 101; the third LED unit 60 can be driven independently by the driving panel 10.

In some embodiments, the color of the light emitted by the third LED unit 60, the color of the light emitted by the first LED unit 20, and the color of the light emitted by the second LED unit 40 are all different; the first LED unit 20. The second LED unit 40 and the third LED unit 60 realize full-color display, and the above three share the first contact 101. The light emitted by the three does not overlap on the driving panel 10, making the LED units highly integrated. This enables high-resolution and high-brightness display effects.

In some embodiments, the first LED unit 20, the second LED unit 40, and the third LED unit 60 may have a trapezoidal structure. That is, the side walls of the first LED unit 20 , the second LED unit 40 , and the third LED unit 60 may be sloped, and the angle between the side walls and the top surface may be an obtuse angle, thereby improving the light concentrating effect of the LED units. It should be understood that the first LED unit 20, the second LED unit 40, and the third LED unit 60 may also have a columnar structure. In this case, the angle between the side wall and the top surface of the LED table is a right angle.

In some embodiments, the first LED unit 20 , the second LED unit 40 , and the third LED unit 60 have a step structure. The step structure includes a first doped semiconductor layer 201 , a second doped semiconductor layer 202 and two active layer 203 between them. It can be understood that the step structure can prevent current interference between adjacent LED units and improve the independence and stability of the LED units.

In some embodiments, the first doped semiconductor layer 201 and the second doped semiconductor layer 202 may include materials based on IIVI materials (such as ZnSe or ZnO) or IIIV nitride materials (such as GaN, AIN, InN, InGaN, GaP , AlInGaP, AlGaAs and their alloys) one or more layers.

In some implementations, the first doped semiconductor layer 201 may be p-type GaN. In some implementations, the first doped semiconductor layer 201 may be p-type InGaN. In some implementations, the first doped semiconductor layer 201 may be p-type AlInGaP.

In some implementations, the second doped semiconductor layer 202 may be n-type GaN. In some implementations, the second doped semiconductor layer 202 may be n-type InGaN. In some implementations, the second doped semiconductor layer 202 may be n-type AlInGaP.

In some embodiments, active layer 203 is the active area of the LED unit. The active layer 203 is disposed between the first doped semiconductor layer 201 and the second doped semiconductor layer 202 and provides light. The active layer 203 is a layer that recombines holes and electrons respectively supplied from the first doped semiconductor layer 201 and the second doped semiconductor layer 202 and outputs light of a specific wavelength, and may have a single A quantum well structure or multiple quantum well (MQW) structure and well layers and barrier layers are alternately stacked.

In some embodiments, further referring to FIG. 3, FIG. 4, FIG. 5, FIG. 6 and FIG. 19, FIG. 3 shows a first LED unit 20, a second LED unit 40, and a third LED unit 60. Schematic diagram of the pixel unit; wherein, the MicroLED microdisplay chip also includes: a first bonding layer 100, a second bonding layer 200 and a third bonding layer 300; the first bonding layer 100 is located between the driving panel 10 and the first LED unit 20 , the second bonding layer 200 is located between the first planarization layer 30 and the second LED unit 40 , and the third bonding layer 300 is located between the second planarization layer 50 and the third LED unit 60 . The first bonding layer 100, the second bonding layer 200 and the third bonding layer 300 may be non-conductive materials or conductive materials, which are sufficient for bonding the LED units.

In some embodiments, the driving panel 10 further includes a first common contact, and the first doped semiconductor layer 201 of the first LED unit 20 is connected to the corresponding first common contact; the driving panel 10 further includes a second common contact. point, the first doped semiconductor layer 201 of the second LED unit 40 is connected to the corresponding second common contact; the driving panel 10 also includes a third common contact, the first doped semiconductor layer of the third LED unit 60 201 is connected to the corresponding third public contact. It should be noted that the first LED unit 20 , the second LED unit 40 , and the third LED unit 60 can be driven individually by the driving panel 10 through time sharing. Time sharing driving can be understood as: turning the first LED on at the first moment. The first doped semiconductor layer 201 of the unit 20 is connected to the corresponding first common contact, and the second doped semiconductor layer 202 of the first LED unit 20 is connected to the first contact at the same time, so that the first LED unit 20 can Being lit at the first moment realizes that the first LED unit 20 can be driven individually by one or more driving circuits and emits light of the corresponding color; of course, the time-sharing driving of the second LED unit 40 and the third LED unit 60 Similar to the above principle, at the second moment and the third moment respectively, with the cooperation of the corresponding common contact and the first contact, the second LED unit 40 and the third LED unit 60 are lit and emit corresponding colors. of light.

In some embodiments, the first contact 101 may be a cathode metal contact, and the first, second and third common contacts may be anode metal contacts. The first common contact point, the second common contact point and the third common contact point may be multiple and distributed on the driving panel 10 . The first contact point 101 may be a contact point shared by LED units of different colors. The first common contact point, the second common contact point and the third common contact point are respectively common electrode contacts of LED units of the same layer and the same color. The contact, the second common contact, and the third common contact are independently connected to each LED unit, apply an anode voltage, and provide a separate drive signal, thereby achieving the purpose of individually controlling each LED unit to emit light.

In some embodiments, the first bonding layer 100, the second bonding layer 200, and the third bonding layer 300 are adhesive material layers, and they also need to be electrically connected to the first doped semiconductor layer 201 to achieve electrical conductivity. The role of conduction. In some embodiments, the first bonding layer 100 , the second bonding layer 200 , and the third bonding layer 300 may be, for example, metal or metal alloy. In some embodiments, the first bonding layer 100, the second bonding layer 200, and the third bonding layer 300 may include Au, Ag, Cu, Al, etc., and are not limited thereto. It should be understood that the description of the materials of the bonding layer is only illustrative and not restrictive, and those skilled in the art can make changes according to requirements, and all such changes are within the scope of the present invention.

In some embodiments, further referring to FIGS. 18 and 19 , the second bonding layer 200 has a first opening 1 exposing the first LED unit 20 at a position corresponding to the first LED unit 20 , and the second luminescent layer 4 is partially filled. The first opening 1; the third bonding layer 300 has a second opening 3 exposing the first LED unit 20 at a position corresponding to the first LED unit 20; the third bonding layer 300 has a position corresponding to the second LED unit 40 exposing The third opening 5 of the second LED unit 40 and the third luminescent layer 6 are partially filled with the second opening 3 and the third opening 5 .

In some embodiments, further referring to FIG. 4 , the second planarization layer 50 also has a plurality of fourth through holes 502 , the fourth through holes 502 are arranged relative to the first through holes 301 ; the third planarization layer 70 also has a plurality of fourth through holes 502 . A fifth through hole 702 is arranged relative to the fourth through hole 502; the first through hole 301, the fourth through hole 502 and the fifth through hole 702 are connected in sequence and are connected to the first LED unit 20 A first recessed area 400 is formed. It can be understood that the first recessed area 400 is a continuous through area formed by the first through hole 301, the fourth through hole 502 and the fifth through hole 702, and may be in the shape of a column, a bowl or a horn. shape, in order to improve the uniformity of the first LED unit 20 emitting light, the first LED unit 20 can be disposed at the center of the first recessed area 400, so that the first color light can evenly pass through the first through hole 301, the fourth Through hole 502 and fifth through hole 702 .

In some embodiments, further referring to FIG. 5 , the third planarization layer 70 also has a plurality of sixth through holes 703 , and the sixth through holes 703 are arranged relative to the second through holes 501 ; the sixth through holes 703 are connected to the second through holes 501 . The hole 501 is connected and forms a second recessed area 500 with the second LED unit 40 . It can be understood that the second recessed area 500 is a continuous through area formed by the sixth through hole 703 and the second through hole 501 communicating and facing each other. It can be columnar, bowl-shaped or trumpet-shaped. In order to improve the To ensure the uniformity of light emitted by the two LED units 40, the second LED unit 40 can be disposed at the center of the second recessed area 500, so that the second color light can uniformly pass through the second through hole 501 and the sixth through hole 703.

In some embodiments, further referring to FIG. 6 , a third recessed area 600 is formed between the third through hole 701 and the third LED unit 60; it can be understood that the third recessed area 600 can be columnar or bowl-shaped. or horn shape. In order to improve the uniformity of the third LED unit 60 emitting light, the third LED unit 60 can be disposed at the center of the third recessed area 600 so that the third color light can pass through the third through hole 701 uniformly.

In some embodiments, referring to FIG. 18 , the apertures of the first through hole 301 , the fourth through hole 502 and the fifth through hole 702 are smaller than the aperture of at least one of the first opening hole 1 and the second opening hole 3 ; The diameters of the through hole 501 and the sixth through hole 703 are smaller than the diameter of the third opening 5 . It can be understood that the size of the hole is determined by the shape of the hole. Generally speaking, the first through hole 301, the fourth through hole 502, the fifth through hole 702, the second through hole 501, and the sixth through hole 703 And the shapes of the first opening 1, the second opening 3, and the third opening 5 are circular, that is, the hole diameter is the inner diameter of the circular hole; of course, the shape of the hole is not limited to the above shape, and can also be a triangle or a square. , regular pentagon, regular hexagon and other regular polygons, the size of the aperture can be determined according to unified standards according to their respective shapes. For example, the aperture of a square can be the distance from the center to the sides, where the center refers to the inscribed part of the polygon. The center of a circle or circumscribed circle. By setting the above-mentioned aperture size relationship, short circuits between the reflective layer and the bonding layer caused by excessively large through-hole apertures can be avoided.

In some embodiments, each of the above through holes can be formed by dry etching. For example, the side walls of the through holes can be etched into vertical surfaces, and the distance between the side walls of the through holes and the top surface of the planarization layer The included angle is a right angle. The structure of the through hole can also be a bowl-shaped structure or a horn-shaped structure, so that the emitted light of the LED can be collimated. The embodiments of the present application do not specifically limit the material of the planarization layer having multiple through holes. The materials of the first planarization layer 30 , the second planarization layer 50 , and the third planarization layer 70 may include, for example, organic resin. Black matrix photoresist, color filter photoresist, and polyimide, etc.

In some embodiments, referring to Figure 2, the MicroLED microdisplay chip further includes: a leveling layer 80, the leveling layer 80 includes a first leveling unit 801, a second leveling unit 802 and a third leveling unit 803; The filling unit 801 fills the first depressed area 400 , the second filling unit 802 fills the second depressed area 500 , and the third filling unit 803 fills the third depressed area 600 . It can be understood that the filling layer 80 is made of transparent material so that the light emitted by the corresponding LED unit is not blocked. The first leveling unit 801 can completely cover the first LED unit 20, the second leveling unit 802 can completely cover the second LED unit 40, and the third leveling unit 803 can completely cover the third LED unit 60; it should be noted that, The leveling layer 80 can protect the first LED unit 20 , the second LED unit 40 and the third LED unit 60 , and can also effectively utilize the light emitting surface and side light of the LED unit to improve the light emitting efficiency.

In some embodiments, referring to FIG. 2 , the MicroLED microdisplay chip further includes: a reflective layer 90 , the reflective layer 90 is provided on the sidewall of any one of the first recessed area 400 , the second recessed area 500 , and the third recessed area 600 . Further, the reflective layer 90 is provided on the side wall of at least one of the first through hole 301, the second through hole 501, the third through hole 701, the fourth through hole 502, the fifth through hole 702, and the sixth through hole 703. .

It can be understood that the reflective layer 90 can not only effectively block light leakage from the side walls of the LED unit, but also reflect the light emitted by the LED unit, and the grid holes provided with the reflective layer 90 can also gather and collimate the reflected light of the reflective layer 90 and the light emitted by the LED unit, which can further improve the light extraction efficiency.

In some embodiments, the reflective layer 90 can be formed based on the first recessed area 400, the second recessed area 500, and the third recessed area 600, which can avoid processing in the tiny gaps between the LED units of the MicroLED microdisplay chip. , thus greatly reducing the processing difficulty, widening the process window, improving the processing yield, and can be applied to products with high resolution and high pixel density.

In some embodiments, the reflective layer 90 can be made of organic materials. Optional organic materials include but are not limited to highly reflective organic paints. The reflective layer 90 can also be made of inorganic materials. Optional inorganic materials include but are not limited to metal materials, such as Al, Cu, Ag, etc. The reflective layer 90 can be deposited on the sidewall of the corresponding area through atomic layer deposition (ALD), chemical vapor deposition (Chemical Vapor Deposition, CVD), evaporation, sputtering, or other methods.

In some embodiments, the first LED unit 20 can emit a first color light, and the first color light includes but is not limited to: any one of red light, green light, blue light, yellow light or ultraviolet light; the second LED unit 40 can emit a second color light, the second color light includes but is not limited to: any one of red light, green light, blue light, yellow light or ultraviolet light; the third LED unit 60 can emit a third color light, the third Colored light includes but is not limited to: any one of red light, green light, blue light, yellow light or ultraviolet light.

In some embodiments, the first color light, the second color light and the third color light are respectively selected from one of: red light, green light and blue light. Among them, the first color light, the second color light, and the third color light are all different.

In some embodiments, further referring to Figures 4, 5 and 6, the MicroLED microdisplay chip also includes; a first passivation layer 21, a first electrode layer 22, a first protective layer 23, a second passivation layer 41, The second electrode layer 42, the second protective layer 43, the third passivation layer 61, the third electrode layer 62 and the third protective layer 63; the first passivation layer 21 covers the first LED unit 20 and the first bonding layer 100 , the first passivation layer 21 has a first opening 210 that exposes the second doped semiconductor layer 202 of the first LED unit 20; the first electrode layer 22 uses the first opening 210 to dope the second doped layer of the first LED unit 20. The type semiconductor layer 202 is electrically connected to the corresponding first contact 101; the first protective layer 23 covers the first passivation layer 21 and the first electrode layer 22; the second passivation layer 41 covers the second LED unit 40 and the second The bonding layer 200 and the second passivation layer 41 have a second opening 410 that exposes the second doped semiconductor layer 202 of the second LED unit 40; the second electrode layer 42 passes through the second opening 410 to expose the second doped semiconductor layer 202 of the second LED unit 40. The second doped semiconductor layer 202 is electrically connected to the corresponding first contact 101; the second protective layer 43 covers the second passivation layer 41 and the second electrode layer 42; the third passivation layer 61 covers the third LED unit 60 and the third bonding layer 300, the third passivation layer 61 has a third opening 610 exposing the second doped semiconductor layer 202 of the third LED unit 60; the third electrode layer 62 passes the third opening 610 The second doped semiconductor layer 202 of the LED unit 60 is electrically connected to the corresponding first contact 101; the third protective layer 63 covers the third passivation layer 61 and the third electrode layer 62.

In some embodiments, the materials of the first passivation layer 21, the second passivation layer 41, and the third passivation layer 61 include inorganic materials or organic materials to isolate and protect the LED unit. The inorganic materials include SiO ₂ , Al ₂ O ₃ , ZrO ₂ , TiO ₂ , Si ₃ N ₄ , HfO ₂ any one or a combination of several; organic materials include black matrix photoresist, color filter photoresist, polyimide, retaining wall Any one or a combination of BANK, Overcoat glue, near-UV negative photoresist, and phenylpropylcyclobutene.

In some embodiments, the first electrode layer 22, the second electrode layer 42, and the third electrode layer 62 are N-pole metal layers, and the material may be indium tin oxide, Cr, Ti, Pt, Au, Al, Cu, Ge or Ni et al.

In some embodiments, the first protective layer 23, the second protective layer 43, and the third protective layer 63 can cover multiple LED units to prevent etching from damaging the light-emitting surface of the LED or the first electrode layer 22 and the second electrode layer. 42. At least one of the third electrode layers 62 . The first protective layer 23, the second protective layer 43, and the third protective layer 63 can all transmit the light emitted by the LED unit, so the first protective layer 23, the second protective layer 43, and the third protective layer 63 should have sufficient transparency. Generally, materials such as silicon dioxide, silicon nitride, and alumina can be used. It should be noted that the first protective layer 23, the second protective layer 43, and the third protective layer 63 are all continuous film layer structures, located at the lower part of the grid layer and at the upper part of the LED unit. The thickness of the first protective layer 23, the second protective layer 43, and the third protective layer 63 may be, for example, 300 to 800 nm. Of course, the thickness may also be selected according to specific circumstances.

In some embodiments, the MicroLED microdisplay chip also includes: a plurality of conductive pillars 900, the conductive pillars 900 are provided on the corresponding first contacts 101 and connected to the corresponding first contacts 101; the conductive pillars 900 extend along the edge away from the driving panel. The direction of 10 sequentially penetrates the first passivation layer 21, the first protective layer 23, the first planarization layer 30, the second passivation layer 41, the second protective layer 43, the second planarization layer 50, and the third passivation layer. 61. The conductive pillar 900 collectively connects the corresponding first electrode layer 22, the corresponding second electrode layer 42, and the corresponding third electrode layer 62. It can be understood that the conductive pillar 900 connects the first electrode layer 22, the second electrode layer 42 and the third electrode layer 62, so that they can jointly participate in the transmission and distribution of current, ensuring that the current can flow through each electrode layer, thereby achieving Normal lighting of the LED unit. Referring further to FIGS. 4-6 , when the conductive pillar 900 penetrates the first passivation layer 21 , the second passivation layer 41 and the third passivation layer 61 , it is also necessary to pay attention to the connection between the conductive pillar 900 and the first bonding layer 100 and 61 . The electrical isolation between the second bonding layer 200 and the third bonding layer 300 avoids possible interference with the conductive pillars 900 when the first bonding layer 100 , the second bonding layer 200 and the third bonding layer 300 are made of conductive materials. short circuit. Further, the conductive pillar 900 is made of metal material.

In some embodiments, taking FIG. 3 as an example, at least one first LED unit 20, at least one second LED unit 40, and at least one third LED unit 60 form a full-color pixel unit of a MicroLED microdisplay chip.

In some embodiments, the top surface of the first flattening unit 801, the top surface of the second flattening unit 802, and the top surface of the third flattening unit 803 are flush with the top surface of the third planarization layer 70; or, The top surfaces of the first flattening unit 801 , the second flattening unit 802 , and the third flattening unit 803 are lower than the top surface of the third planarization layer 70 . It can be understood that the flush structure can not only effectively prevent optical crosstalk between adjacent LED units, but also ensure the flatness and stability of the Micro LED microdisplay chip structure, which facilitates subsequent production processes.

In some embodiments, the size of the first LED unit 20, the second LED unit 40, and the third LED unit 60 is 0.1 to 5 microns; the adjacent first LED unit 20, the second LED unit 40, and the third LED unit The spacing between 60 is 1~10 microns.

In some embodiments, the driving panel 10 may include semiconductor materials such as silicon, silicon carbide, nitride, germanium, arsenide, and indium phosphide. The driving panel 10 may have a driving circuit formed therein, and may be a CMOS backplane or a TFT glass substrate.

In some embodiments, referring to Figure 2, the MicroLED microdisplay chip also includes: a microlens array 700. The microlens array 700 includes a plurality of microlens units 800. The microlens units 800 are provided in the first LED unit 20 and the second LED unit. 40. Above at least one of the third LED units 60 . Specifically, the microlens unit 800 is provided on the third planarization layer 70 and covers at least one of the first recessed area 400, the second recessed area 500, and the third recessed area 600. The microlens unit 800 can be used to gather and/or collimate the light emitted by the LED unit, thereby improving the luminous efficiency of the Micro LED microdisplay chip. The light-emitting curved surface of the microlens unit 800 may be an irregular curved surface or a regular curved surface. For example, the light-emitting curved surface may be an arc-shaped curved surface or a hemispherical curved surface. The ratio of the curvature radius of the light-emitting curved surface of the microlens unit 800 to the size of the LED unit is set at 0.5-3.

In some embodiments, taking the MicroLED microdisplay chip in Figure 19 as an example, a method for preparing a MicroLED microdisplay chip is provided, including:

A driving panel 10 is provided, and the driving panel 10 includes a plurality of first contacts 101;

A first light-emitting layer 2 is formed on the driving panel 10. The first light-emitting layer 2 includes a plurality of first LED units 20. The first LED units 20 are arranged on the driving panel 10. The first LED units 20 are used to emit a first color. Light;

A second light-emitting layer 4 is formed above the first light-emitting layer 2. The second light-emitting layer 4 includes a plurality of second LED units 40 arranged in an array, and the second LED units 40 are used to emit light of the second color;

Wherein, the orthographic projections of the first LED unit 20 and the second LED unit 40 on the driving panel 10 do not overlap; the second doped semiconductor layer 202 of the first LED unit 20 and the adjacent at least one second LED unit 40 The second doped semiconductor layer 202 is electrically connected to the driving panel 10 through the first contact 101; the first LED unit 20 and the second LED unit 40 can be driven individually by the driving panel 10 through time sharing.

Referring further to Figures 20-27, cross-sectional views of different stages in the preparation process of the MicroLED microdisplay chip shown in Figure 19 are schematically illustrated.

Referring to Figure 20, a driving panel 10 is provided first. The driving panel 10 may include a circuit layer composed of a complementary metal oxide semiconductor CMOS device or a TFT device. These CMOS devices or TFT devices may form a driving circuit in the driving panel 10. The driving panel 10 may also include a plurality of contacts connected to the driving circuit. The plurality of contacts include a first contact 101 and a first common contact, a second common contact and a third common contact. The first contacts 101 may be respectively Correspondingly electrically connected to the second doped semiconductor layer 202 of each LED unit, the first common contact, the second common contact and the third common contact are respectively connected to the first doped semiconductor layer 201 of the plurality of LED units. Electrically connected to individually drive any one of the plurality of LED units to emit light; then the first bonding layer 100 can be formed on the driving panel 10; and then the substrate with the first LED epitaxial layer 11 formed thereon is passed through the first The bonding layer 100 is bonded to the driving panel 10 so that the first LED epitaxial layer 11 is formed on the driving panel 10 .

Specifically, the first LED epitaxial layer 11 on the substrate can be turned over, and the first bonding layer 100 can be formed by fusing the bonding layers. Therefore, the first LED epitaxial layer 11 can be bonded to the driving panel 10, and then the substrate can be peeled off. The peeling method includes but is not limited to laser peeling, dry etching, wet etching, mechanical polishing, etc.; after flipping The first LED epitaxial layer 11 can also undergo a thinning operation, and the thinning operation includes dry etching, wet etching or mechanical polishing.

Referring to Figure 21, the MESA pattern can be designed according to the patterned mask, and the first LED epitaxial layer 11 can be etched to form a plurality of first LED units 20. The first LED units 20 are functional step structures. The unit 20 includes a first doped semiconductor layer 201, an active layer 203 and a second doped semiconductor layer 202. It should be understood that etching includes dry or wet methods.

Referring to FIG. 22 , the first passivation layer 21 is first deposited on the first LED unit 20 and the first bonding layer 100 , and then the first passivation layer 21 corresponds to the second doped semiconductor layer of the first LED unit 20 . A first opening 210 is provided at the position 202, and then a first electrode layer 22 is provided, located on the upper part of the driving panel and outside the passivation layer. The first electrode layer 22 connects the second electrode of the first LED unit 20 through the first opening 210. The doped semiconductor layer 202 is electrically connected to the corresponding first contact 101 .

Referring to FIG. 23 , a first planarization layer 30 may be formed on the upper part of the plurality of first LED units 20 . The material of the first planarization layer 30 may include organic resin, organic black matrix photoresist, and color filter photoresist. , and polyimide, etc.

Referring to FIG. 24 , the second LED unit 40 is first formed on the first planarization layer 30 in the same manner as the first LED unit 20 ; where, an exposure needs to be formed at the position of the second bonding layer 200 corresponding to the first LED unit 20 The first opening 1 of the first LED unit 20 is such that the second passivation layer 41 of the second light-emitting layer 4 partially fills the first opening 1 .

Referring to FIG. 25 , a second planarization layer 50 may be formed on the upper part of the plurality of second LED units 40 . The material of the second planarization layer 50 may include organic resin, organic black matrix photoresist, and color filter photoresist. , and polyimide, etc.

Referring to Figure 26, the third LED unit 60 is first formed on the second planarization layer 50 in the same manner as the first LED unit 20 and the second LED unit 40; wherein, the third bonding layer 300 needs to be The second opening 3 is formed at the position of the LED unit 20 to expose the first LED unit 20; and the third opening 5 is formed at the position of the third bonding layer 300 corresponding to the second LED unit 40 to expose the second LED unit 40; The third passivation layer 61 of the three light-emitting layers 6 is partially filled in the second opening 3 and the third opening 5 .

Referring to Figures 27 and 19, a third planarization layer 70 is first formed on the upper part of the plurality of third LED units 60. The material of the third planarization layer 70 may include organic resin, organic black matrix photoresist, color filter, etc. Photoresist, polyimide, etc.; then a microlens array 700 is set on the third planarization layer 70. The microlens array 700 includes a plurality of microlens units 800, and the microlens unit 800 covers the first LED unit 20, At least one of the second LED unit 40 and the third LED unit 60 obtains a MicroLED microdisplay chip.

In some embodiments, taking the preparation of the MicroLED microdisplay chip in Figure 2 as an example, the preparation method includes the following steps:

A driving panel 10 is provided, and the driving panel 10 includes a plurality of first contacts 101;

A first light-emitting layer 2 is formed on the driving panel 10. The first light-emitting layer 2 includes a plurality of first LED units 20, and the first LED units 20 are used to emit light of a first color;

A first planarization layer 30 is formed. The first planarization layer 30 has a plurality of first through holes 301 . The plurality of first through holes 301 are respectively arranged around the first LED unit 20 . The first color light passes through the first through holes 301 shoot out;

A second light-emitting layer 4 is formed on the first planarization layer 30. The second light-emitting layer 4 includes a plurality of second LED units 40 arranged in an array, and the second LED units 40 are used to emit second color light;

A second planarization layer 50 is formed. The second planarization layer 50 has a plurality of second through holes 501 . The plurality of second through holes 501 are respectively arranged around the second LED unit 40 . The second color light is emitted through the second through holes 501 ;

Wherein, the orthographic projections of the first LED unit 20 and the second LED unit 40 on the driving panel 10 do not overlap; the second doped semiconductor layer 202 of the first LED unit 20 and the adjacent at least one second LED unit 40 The second doped semiconductor layer 202 is electrically connected to the driving panel 10 through the first contact 101; the first LED unit 20 and the second LED unit 40 can be driven individually by the driving panel 10 through time sharing.

It can be understood that this preparation method does not need to distinguish the production order when preparing multiple layers of LED units for emitting light of different colors, and can be freely sequenced, simplifying the preparation difficulty; and each layer of LED units emits light independently, and the LEDs are surrounded by grid holes. The unit method forms an independent and penetrating reflective structure on the grid layer, improving the light extraction efficiency of different LED units.

In some embodiments, the preparation method further includes:

A third light-emitting layer 6 is formed on the second planarization layer 50. The third light-emitting layer 6 includes a plurality of third LED units 60 arranged in an array, and the third LED units 60 are used to emit third color light;

A third planarization layer 70 is formed. The third planarization layer 70 has a plurality of third through holes 701. The plurality of third through holes 701 are respectively arranged around the third LED unit 60. The third color light is emitted through the third through holes 701. ;

Among them, the orthographic projection of the third LED unit 60 and any one of the first LED unit 20 and the second LED unit 40 on the driving panel 10 does not overlap; the second doped semiconductor layer 202 of the third LED unit 60, The second doped semiconductor layer 202 of at least one adjacent first LED unit 20 and the second doped semiconductor layer 202 of at least one adjacent second LED unit 40 are electrically connected to the corresponding first contact 101 Connection; the third LED unit 60 can be driven individually by the driving panel 10 through time sharing.

In some embodiments, before forming the plurality of first LED units 20 on the driving panel 10 , the method further includes: forming a first bonding layer 100 on the driving panel 10 , the first bonding layer 100 being located between the driving panel 10 and the first LED unit 20 . between an LED unit 20; the driving panel 10 also includes a first common contact, and the first doped semiconductor layer 201 of the first LED unit 20 is connected to the corresponding first common contact;

Before forming the plurality of second LED units 40 on the first planarization layer 30 , the method further includes: forming a second bonding layer 200 on the first planarization layer 30 , the second bonding layer 200 being located on the first planarization layer. 30 and the second LED unit 40; the driving panel 10 also includes a second common contact, and the first doped semiconductor layer 201 of the second LED unit 40 is connected to the corresponding second common contact;

Before forming the plurality of third LED units 60 on the second planarization layer 50 , the method further includes: forming a third bonding layer 300 on the second planarization layer 50 , the third bonding layer 300 being located on the second planarization layer. 50 and the third LED unit 60; the driving panel 10 further includes a third common contact, and the first doped semiconductor layer 201 of the third LED unit 60 is connected to the corresponding third common contact.

In some embodiments, the preparation method further includes: forming a filling layer 80; the filling layer 80 includes a first filling unit 801, a second filling unit 802 and a third filling unit 803; the first filling unit 801 fills The first recessed area 400 is filled with the second recessed area 500 by the second filling unit 802, and the third recessed area 600 is filled with the third recessed area 603 by the third filling unit 803.

In some embodiments, before forming the leveling layer 80, the preparation method further includes:

The reflective layer 90 is formed on the side wall of any one of the first recessed area 400, the second recessed area 500, and the third recessed area 600; or,

A reflective layer 90 is formed on the side wall of at least one of the first through hole 301 , the second through hole 501 , the third through hole 701 , the fourth through hole 502 , the fifth through hole 702 , and the sixth through hole 703 .

In some embodiments, after forming the leveling layer 80 , the preparation method further includes:

A microlens array 700 is formed on the third planarization layer 70 . The microlens array 700 includes a plurality of microlens units 800 . The microlens units 800 cover the first recessed area 400 , the second recessed area 500 , and the third recessed area 600 . At least one.

In some embodiments, the step of forming the first luminescent layer 2 on the driving panel 10 further includes: forming a plurality of first LED units 20 , a first passivation layer 21 , a first electrode layer 22 and a first protective layer 23 , the first passivation layer 21 covers the first LED unit 20 and the first bonding layer 100, the first passivation layer 21 has a first opening 210 exposing the second doped semiconductor layer 202 of the first LED unit 20, An electrode layer 22 electrically connects the second doped semiconductor layer 202 of the first LED unit 20 to the corresponding first contact 101 through the first opening 210. The first protective layer 23 covers the first passivation layer 21 and the first contact 101. an electrode layer 22;

The step of forming the second light-emitting layer 4 further includes: forming a plurality of second LED units 40, a second passivation layer 41, a second electrode layer 42 and a second protective layer 43, the second passivation layer 41 covering the second LED unit 40 and the second bonding layer 200, the second passivation layer 41 has a second opening 410 exposing the second doped semiconductor layer 202 of the second LED unit 40, and the second electrode layer 42 passes through the second opening 410. The second doped semiconductor layer 202 of the LED unit 40 is electrically connected to the corresponding first contact 101, and the second protective layer 43 covers the second passivation layer 41 and the second electrode layer 42;

The step of forming the third light-emitting layer 6 further includes: forming a plurality of third LED units 60, a third passivation layer 61, a third electrode layer 62 and a third protective layer 63, the third passivation layer 61 covering the third LED unit 60 and the third bonding layer 300, the third passivation layer 61 has a third opening 610 exposing the second doped semiconductor layer 202 of the third LED unit 60, the third electrode layer 62 passes the third opening 610 The second doped semiconductor layer 202 of the LED unit 60 is electrically connected to the corresponding first contact 101 , and the third protective layer 63 covers the third passivation layer 61 and the third electrode layer 62 .

In some embodiments, forming the plurality of first LED units 20 includes:

A first substrate is provided. A first LED epitaxial layer 11 is provided on the first substrate. The first LED epitaxial layer 11 includes a stacked first doped semiconductor layer 201, an active layer 203 and a second doped semiconductor. layer202;

The driving panel 10 and the first LED epitaxial layer 11 are bonded and connected through the first bonding layer 100;

Remove the first substrate and expose the second doped semiconductor layer 202 of the first LED epitaxial layer 11;

According to the MESA pattern designed by the patterned mask, the first LED epitaxial layer 11 is etched to form a plurality of first LED units 20 .

In some embodiments, the step of forming a plurality of second LED units 40 includes:

A second substrate is provided, and a second LED epitaxial layer 12 is provided on the second substrate. The second LED epitaxial layer 12 includes a stacked first doped semiconductor layer 201, an active layer 203, and a second doped semiconductor layer. layer202;

The first planarization layer 30 and the second LED epitaxial layer 12 are bonded and connected through the second bonding layer 200;

Remove the second substrate and expose the second doped semiconductor layer 202 of the second LED epitaxial layer 12;

The second LED epitaxial layer 12 is etched according to the MESA pattern designed by the patterned mask to form a plurality of second LED units 40 .

In some embodiments, the step of forming a plurality of third LED units 60 includes:

A third substrate is provided, and a third LED epitaxial layer 13 is provided on the third substrate. The third LED epitaxial layer 13 includes a stacked first doped semiconductor layer 201, an active layer 203, and a second doped semiconductor layer. layer202;

The second planarization layer 50 and the third LED epitaxial layer 13 are bonded and connected through the third bonding layer 300;

Remove the third substrate and expose the second doped semiconductor layer 202 of the third LED epitaxial layer 13;

According to the MESA pattern designed by the patterned mask, the third LED epitaxial layer 13 is etched to form a plurality of third LED units 60 .

In some embodiments, the first LED epitaxial layer 11 is an epitaxial layer that emits red light, the second LED epitaxial layer 12 is an epitaxial layer that emits green light, and the third LED epitaxial layer 13 is an epitaxial layer that emits blue light.

In some embodiments, the first substrate, the second substrate, and the third substrate may be made of glass, sapphire, silicon carbide, or other materials.

In some embodiments, before forming the first electrode layer 22 , the second electrode layer 42 and the third electrode layer 62 , the method further includes:

Conductive pillars 900 are formed, and the conductive pillars 900 are disposed on the first contacts 101 and connected to the corresponding first contacts 101; the conductive pillars 900 sequentially penetrate the first passivation layer 21 and the first protective layer in the direction away from the driving panel 10. 23. The first planarization layer 30, the second passivation layer 41, the second protective layer 43, the second planarization layer 50, and the third passivation layer 61 to simultaneously connect the first electrode layer 22 and the second electrode layer 42 and third electrode layer 62.

Figures 7 to 18 show cross-sectional views of different stages in the preparation process of MicroLED microdisplay chips.

Referring to Figure 7, a driving panel 10 is provided first. The driving panel 10 may include a circuit layer composed of a complementary metal oxide semiconductor CMOS device or a TFT device. These CMOS devices or TFT devices may form a driving circuit in the driving panel 10. The driving panel 10 may also include a plurality of contacts connected to the driving circuit. The plurality of contacts include a first contact 101 and a first common contact, a second common contact and a third common contact. The first contacts 101 may be respectively Correspondingly electrically connected to the second doped semiconductor layer 202 of each LED unit, the first common contact, the second common contact and the third common contact are respectively connected to the first doped semiconductor layer 201 of the plurality of LED units. Electrically connected to individually drive any one of the plurality of LED units to emit light; then the first bonding layer 100 can be formed on the driving panel 10; and then the substrate with the first LED epitaxial layer 11 formed thereon is passed through the first The bonding layer 100 is bonded to the driving panel 10 so that the first LED epitaxial layer 11 is formed on the driving panel 10 .

Specifically, the first LED epitaxial layer 11 on the substrate can be turned over, and the first bonding layer 100 can be formed by fusing the bonding layers. Therefore, the first LED epitaxial layer 11 can be bonded to the driving panel 10, and then the substrate can be peeled off. The peeling method includes but is not limited to laser peeling, dry etching, wet etching, mechanical polishing, etc.; after flipping The first LED epitaxial layer 11 can also undergo a thinning operation, and the thinning operation includes dry etching, wet etching or mechanical polishing.

Referring to Figure 8, the MESA pattern can be designed according to the patterned mask, and the first LED epitaxial layer 11 can be etched to form a plurality of first LED units 20. The first LED units 20 are functional step structures. The unit 20 includes a first doped semiconductor layer 201, an active layer 203 and a second doped semiconductor layer 202. It should be understood that etching includes dry or wet methods.

Referring to FIG. 9 , a first passivation layer 21 is first deposited on the first LED unit 20 and the first bonding layer 100 , and then the first passivation layer 21 corresponds to the second doped semiconductor layer of the first LED unit 20 A first opening 210 is provided at the position 202, and then a first electrode layer 22 is provided, located on the upper part of the driving panel and outside the passivation layer. The first electrode layer 22 connects the second electrode of the first LED unit 20 through the first opening 210. The doped semiconductor layer 202 is electrically connected to the corresponding first contact 101; then the first protective layer 23 is formed on the surface of the first passivation layer 21 and the first electrode layer 22, and the etching barrier layer 407 may include the first An etching barrier layer on the passivation layer 21 and an etching barrier layer on the first electrode layer 22 .

Referring to FIG. 10 , a first planarization layer 30 may be formed on the upper part of the plurality of first LED units 20 . The material of the first planarization layer 30 may include organic resin, organic black matrix photoresist, and color filter photoresist. , and polyimide; perform photolithography or etching on the first planarization layer 30 to form a plurality of first through holes 301 . The plurality of first through holes 301 may be respectively arranged around the plurality of first LED units 20, and a recessed area is formed between the first LED units 20 and the corresponding grid holes. It should be understood that the plurality of first through holes are arranged in one-to-one correspondence with the plurality of first LED units, so that the emitted light can be emitted through the grid holes. The first through hole 301 may be formed by dry etching, and the first through hole 301 exposes the first protective layer 23 . Since the first protective layer 23 covers the upper part of the LED and the upper part of the first electrode layer 22, damage to the first LED unit can be prevented during the etching of the grid holes.

Referring to Figure 11, in order to improve the reflection effect of the light emitted by the first LED unit 20, a reflective layer 90 can be formed on the side wall of the first through hole 301. The reflective layer 90 can be formed by atomic layer deposition (ALD) or chemical vapor deposition (CVD). Deposited on the side wall of the first through hole 301 by evaporation, sputtering or other methods.

Referring to FIG. 12 , a filling layer 80 is formed on the first planarization layer. It can be understood that part of the first filling unit 801 is filled in the first through hole 301 , for example, by blocking the remaining area through a mask layer. . The mask layer is removed, and then the filling layer 80 is developed using a developer. Since only the area of the first filling unit 801 is cured by light, the remaining parts will be removed under the action of the developer, so that multiple first filling units 801 can be formed. The first filling unit 801 fills at least part or all of the first through hole 301 .

Referring to Figures 13-17, continue to prepare the second LED unit 40 on the first planarization layer 30. The specific preparation method is the same as that of the first LED unit 20, which will not be described in detail here. However, it should be noted that after the second planarization layer 50 is formed, , it is necessary to form a fourth through hole 502 at a position corresponding to the first through hole 301. The fourth through hole 502 separates the second bonding layer 200, the second passivation layer 41 and the second protective layer 43 from the first through hole. 301, avoid the short circuit caused by the contact between the reflective layer 90 and the second bonding layer 200; and form a second through hole 501 at a position corresponding to the second LED unit 40, and fill the fourth through hole 502 with the first filling unit 801, and the second filling unit 802 is filled in the second through hole 501, and the orthographic projection of any one of the first LED unit 20 and the second LED unit 40 on the driving panel 10 does not overlap.

Referring to Figure 18, continue to prepare the third LED unit 60 on the second planarization layer 50. The specific preparation method is the same as that of the first LED unit 20, which will not be described in detail here. However, it should be noted that after the third planarization layer 70 is formed, it is necessary to A fifth through hole 702 is formed at a position corresponding to the fourth through hole 502, a sixth through hole 703 is formed at a position corresponding to the second through hole 501, and a third through hole 701 is formed at a position corresponding to the third LED unit 60. The fifth through hole 702 and the sixth through hole 703 both need to isolate the third bonding layer 300, the third passivation layer 61 and the third protective layer 63 to avoid short circuit of the reflective layer 90; and in the fifth through hole 702 The first filling unit 801 is filled, the second filling unit 802 is filled in the sixth through hole 703, and the third filling unit 803 is filled in the third through hole 701. The first LED unit 20 and the second LED unit 40 , the orthographic projection of any one of the third LED units 60 on the driving panel 10 does not overlap.

Referring to FIG. 2 , a microlens array 700 is finally provided on the third planarization layer 70 . The microlens array 700 includes a plurality of microlens units 800 . The microlens units 800 cover the first recessed area 400 , the second recessed area 500 , and the third recessed area 500 . At least one of the recessed areas 600 obtains a MicroLED microdisplay chip.

It should be noted that the embodiments of the present application do not specifically limit the sequence of steps in the above method of manufacturing a MicroLED microdisplay chip.

The embodiments of the manufacturing method in this application only describe the manufacturing process or steps. Unexplained device structures, shapes, materials, etc. can refer to the above-mentioned embodiments of MicroLED microdisplay chips and will not be described again here.

The obtained MicroLED microdisplay chip can be used to prepare a display device. The display device can be, for example, a component or device including a MicroLED microdisplay chip, such as a MicroLED microdisplay chip device including an encapsulation layer. The resulting MicroLED microdisplay chip can be further used in electronic devices, including but not limited to: display devices such as augmented reality AR display devices, virtual reality VR display devices, near-eye display NED and head-up display HUD devices, etc.

In the above embodiments, each embodiment is described with its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

The present invention has been introduced in detail above. Specific examples are used in the present invention to illustrate the principles and implementation modes of the present invention. The description of the above embodiments is only used to help understand the technical solution of the present invention and its core idea; in this field, Those of ordinary skill should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not deviate from the essence of the corresponding technical solutions of the present invention. The scope of the technical solution of the embodiment.

Claims (21)

1. Micro LED micro display chip, its characterized in that includes:

   a drive panel including a plurality of first contacts;

   at least two light emitting layers including a first light emitting layer and a second light emitting layer;

   the first light-emitting layer is arranged on the driving panel; the first light-emitting layer comprises a plurality of first LED units, the first LED units are arranged on the driving panel, and the first LED units are used for emitting first color light;

   the second light-emitting layer is arranged above the first light-emitting layer, and comprises a plurality of second LED units which are arranged in an array manner and used for emitting second color light;

   the at least two light-emitting layers further comprise a third light-emitting layer arranged above the second light-emitting layer; the third light-emitting layer comprises a plurality of third LED units which are arranged in an array manner, and the third LED units are used for emitting third color light;

   wherein the front projection of the third LED unit in one full-color pixel unit and any one of the first LED unit and the second LED unit on the driving panel is not overlapped; the second doped semiconductor layer of the third LED unit, the second doped semiconductor layer of at least one adjacent first LED unit and the second doped semiconductor layer of at least one adjacent second LED unit in one full-color pixel unit all share one first contact and are electrically connected with the first contact; the first LED unit, the second LED unit, and the third LED unit can be individually driven by the driving panel by time sharing, respectively.
2. 2. The micro LED micro display chip of claim 1, wherein at least one of the first LED unit, at least one of the second LED unit, and at least one of the third LED unit form one full color pixel unit of the micro LED micro display chip.
3. 3. The micro led micro display chip of claim 2, further comprising:

   a first planarization layer located between the first light-emitting layer and the second light-emitting layer; the first planarization layer transmits the first color light;

   a second planarization layer located between the second light-emitting layer and the third light-emitting layer; the second planarization layer transmits the first color light and the second color light; a plurality of third LED units are arranged on the second planarization layer;

   a third planarization layer disposed on the third light-emitting layer; the third planarization layer transmits the first color light, the second color light, and the third color light.
4. 4. The micro led micro display chip as set forth in claim 3, further comprising:

   a first bonding layer between the driving panel and the first LED unit; the driving panel further comprises a first common contact, and the first doping type semiconductor layer of the first LED unit is connected with the corresponding first common contact;

   A second bonding layer located between the first planarization layer and the second LED unit; the driving panel further comprises a second common contact, and the first doping type semiconductor layer of the second LED unit is connected with the corresponding second common contact;

   a third bonding layer located between the second planarization layer and the third LED unit; the driving panel further includes a third common contact, and the first doping type semiconductor layer of the third LED unit is connected with the corresponding third common contact.
5. 5. The micro led micro-display chip of claim 4, wherein,

   the second bonding layer is provided with a first opening at a position corresponding to the first LED unit;

   the third bonding layer is provided with a second open hole at a position corresponding to the first LED unit; the third bonding layer is provided with a third opening at a position corresponding to the second LED unit.
6. 6. The micro led micro-display chip of claim 5, wherein,

   the first planarization layer is provided with a plurality of first through holes, the plurality of first through holes are respectively arranged around the first LED units, and the first color light is emitted through the first through holes;

   the second planarization layer is provided with a plurality of second through holes, the second through holes are respectively arranged around the second LED units, and the second color light is emitted through the second through holes;

   The third planarization layer is provided with a plurality of third through holes, the third through holes are respectively arranged around the third LED units, and the third color light is emitted through the third through holes;

   the second planarization layer is further provided with a plurality of fourth through holes, and the fourth through holes are arranged relative to the first through holes; the third planarization layer is further provided with a plurality of fifth through holes, and the fifth through holes are arranged relative to the fourth through holes; the first through hole, the fourth through hole and the fifth through hole are sequentially communicated, and a first concave area is formed between the first through hole, the fourth through hole and the fifth through hole and the first LED unit;

   the third planarization layer further has a plurality of sixth through holes, the sixth through holes being disposed opposite to the second through holes; the sixth through hole is communicated with the second through hole, and a second concave area is formed between the sixth through hole and the second LED unit;

   and a third concave region is formed between the third through hole and the third LED unit.
7. 7. The micro led micro-display chip of claim 6, further comprising:

   the filling layer comprises a first filling unit, a second filling unit and a third filling unit; the first filling unit fills the first concave region, the second filling unit fills the second concave region, and the third filling unit fills the third concave region.
8. 8. The micro led micro-display chip of claim 6, further comprising:

   the reflecting layer is arranged on the side wall of any one of the first concave area, the second concave area and the third concave area; or alternatively

   The reflecting layer is arranged on the side wall of at least one of the first through hole, the second through hole, the third through hole, the fourth through hole, the fifth through hole and the sixth through hole.
9. 9. The micro led micro display chip of claim 1, further comprising:

   the micro lens array comprises a plurality of micro lens units, and the micro lens units are arranged above at least one of the first LED units and the second LED units.
10. 10. The micro led micro display chip as set forth in claim 3, wherein the first light emitting layer further includes a first passivation layer and a first electrode layer; the first passivation layer covers the first LED unit, and has a first opening exposing the second doping type semiconductor layer of the first LED unit; the first electrode layer electrically connects the second doped semiconductor layer of the corresponding first LED unit with the corresponding first contact through the first opening;

    The second light emitting layer further includes a second passivation layer covering the second LED unit, the second passivation layer having a second opening exposing the second doped semiconductor layer of the second LED unit; the second electrode layer electrically connects the second doped semiconductor layer of the corresponding second LED unit with the corresponding first contact through the second opening;

    the third light emitting layer further includes a third passivation layer covering the third LED unit, the third passivation layer having a third opening exposing the second doped semiconductor layer of the third LED unit; the third electrode layer electrically connects the second doped semiconductor layer of the third LED unit with the corresponding first contact through the three openings.
11. 11. The micro led micro display chip as set forth in claim 10, wherein the first light emitting layer further includes a first protective layer covering the first passivation layer and the first electrode layer;

    the second light emitting layer further includes a second protective layer covering the second passivation layer and the second electrode layer;

    The third light emitting layer further includes a third protective layer covering the third passivation layer and the third electrode layer.
12. 12. The micro led micro-display chip of claim 10, further comprising:

    the conductive columns are arranged on the corresponding first contacts and connected with the corresponding first contacts;

    the conductive posts are connected with the corresponding first electrode layer, the corresponding second electrode layer and the corresponding third electrode layer.
13. 13. The preparation method of the micro LED micro display chip is characterized by comprising the following steps:

    providing a drive panel comprising a plurality of first contacts;

    forming a first light emitting layer on the driving panel, wherein the first light emitting layer comprises a plurality of first LED units, the first LED units are arranged on the driving panel and used for emitting first color light;

    forming a second light emitting layer above the first light emitting layer, the second light emitting layer comprising a plurality of second LED units arranged in an array, the second LED units being for emitting a second color light;

    forming a third light emitting layer above the second light emitting layer, the third light emitting layer comprising a plurality of third LED units arranged in an array, the third LED units being for emitting a third color light;

    Wherein the front projection of the third LED unit in one full-color pixel unit and any one of the first LED unit and the second LED unit on the driving panel is not overlapped; the second doped semiconductor layer of the third LED unit, the second doped semiconductor layer of at least one adjacent first LED unit and the second doped semiconductor layer of at least one adjacent second LED unit in one full-color pixel unit all share one first contact and are electrically connected with the first contact; the first LED unit, the second LED unit, and the third LED unit can be individually driven by the driving panel by time sharing, respectively.
14. 14. The method for manufacturing a micro LED micro display chip according to claim 13, wherein,

    forming a first planarization layer on the first light emitting layer before forming a second light emitting layer over the first light emitting layer, the first planarization layer transmitting the first color light;

    forming a second planarization layer on the second light-emitting layer before forming a third light-emitting layer over the second light-emitting layer, the second planarization layer transmitting both the first color light and the second color light;

    After forming a third light emitting layer over the second light emitting layer, a third planarization layer is formed over the third light emitting layer, the third planarization layer transmitting the first color light, the second color light, and the third color light.
15. 15. The method for manufacturing a micro led micro display chip according to claim 14, further comprising:

    bonding the driving panel and the first LED unit through a first bonding layer; the driving panel further comprises a first common contact, and the first doping type semiconductor layer of the first LED unit is connected with the corresponding first common contact;

    bonding the first planarization layer and the second LED unit through a second bonding layer; the driving panel further comprises a second common contact, and the first doping type semiconductor layer of the second LED unit is connected with the corresponding second common contact;

    bonding the second planarization layer and the third LED unit through a third bonding layer; the driving panel further includes a third common contact, and the first doping type semiconductor layer of the third LED unit is connected with the corresponding third common contact.
16. 16. The method for manufacturing a micro led micro display chip according to claim 15, further comprising: forming a first opening exposing the first LED unit at a position of the second bonding layer corresponding to the first LED unit;

    And forming a second opening exposing the first LED unit at a position of the third bonding layer corresponding to the first LED unit and forming a third opening exposing the second LED unit at a position of the third bonding layer corresponding to the second LED unit.
17. 17. The method for manufacturing a micro LED micro display chip according to claim 16, wherein,

    forming a plurality of first through holes on the first planarization layer, wherein the plurality of first through holes are respectively arranged around the first LED units, and the first color light exits through the first through holes;

    forming a plurality of second through holes and a plurality of fourth through holes on the second planarization layer, wherein the second through holes are respectively arranged around the second LED units, the second color light is emitted through the second through holes, and the fourth through holes are arranged relative to the first through holes;

    forming a plurality of third through holes through which the third color light exits, a plurality of fifth through holes disposed with respect to the fourth through holes, and a plurality of sixth through holes disposed with respect to the second through holes, on the third planarization layer, the plurality of third through holes being disposed around the third LED unit, respectively;

    The first through hole, the fourth through hole and the fifth through hole are sequentially communicated, and a first concave area is formed between the first through hole, the fourth through hole and the fifth through hole and the first LED unit;

    the sixth through hole is communicated with the second through hole, and a second concave area is formed between the sixth through hole and the second LED unit;

    a third concave region is formed between the third through hole and the third LED unit;

    the method further comprises the steps of: forming a filling layer; the filling layer comprises a first filling unit, a second filling unit and a third filling unit; the first filling unit fills the first concave region, the second filling unit fills the second concave region, and the third filling unit fills the third concave region.
18. 18. The method of claim 17, further comprising, prior to forming the fill layer:

    forming a reflective layer on the side wall of any one of the first concave region, the second concave region and the third concave region; or alternatively

    And forming a reflecting layer on the side wall of at least one of the first through hole, the second through hole, the third through hole, the fourth through hole, the fifth through hole and the sixth through hole.
19. 19. The method of claim 17, further comprising, after forming the fill layer:

    and forming a micro lens array, wherein the micro lens array comprises a plurality of micro lens units, and the micro lens units are arranged above at least one of the first LED units, the second LED units and the third LED units.
20. 20. The method for manufacturing a micro LED micro display chip according to claim 16, wherein,

    the step of forming a first light emitting layer on the driving panel further includes: forming a plurality of first LED units, a first passivation layer and a first electrode layer, wherein the first passivation layer covers the first LED units and the first bonding layer, the first passivation layer is provided with a first opening exposing the second doped semiconductor layer of the first LED units, and the first electrode layer electrically connects the second doped semiconductor layer of the first LED units with the corresponding first contacts through the first opening;

    the step of forming a second light emitting layer on the first planarization layer further includes: forming a plurality of second LED units, a second passivation layer and a second electrode layer, wherein the second passivation layer covers the second LED units and the second bonding layer, the second passivation layer is provided with a second opening exposing a second doping type semiconductor layer of the second LED units, and the second electrode layer electrically connects the second doping type semiconductor layer of the second LED units with the corresponding first contacts through the second opening;

    The step of forming a third light emitting layer on the second planarization layer further includes: and forming a plurality of third LED units, a third passivation layer and a third electrode layer, wherein the third passivation layer covers the third LED units and the third bonding layer, the third passivation layer is provided with a third opening exposing the second doped semiconductor layer of the third LED units, and the third electrode layer electrically connects the second doped semiconductor layer of the third LED units with the corresponding first contact through the third opening.
21. 21. The method of claim 20, wherein the step of forming a plurality of the first LED units comprises:

    providing a first substrate, wherein a first LED epitaxial layer is arranged on the first substrate, and comprises a first doped semiconductor layer, an active layer and a second doped semiconductor layer which are stacked;

    bonding and connecting the driving panel and the first LED epitaxial layer through a first bonding layer;

    removing the first substrate and exposing the second doping type semiconductor layer of the first LED epitaxial layer;

    etching the first LED epitaxial layer to form a plurality of first LED units;

    A step of forming a plurality of the second LED units, comprising:

    providing a second substrate, wherein a second LED epitaxial layer is arranged on the second substrate, and comprises a first doped semiconductor layer, an active layer and a second doped semiconductor layer which are stacked;

    bonding and connecting the first planarization layer and the second LED epitaxial layer through the second bonding layer;

    removing the second substrate and exposing the second doping type semiconductor layer of the second LED epitaxial layer;

    etching the second LED epitaxial layer to form a plurality of second LED units;

    a step of forming a plurality of the third LED units, comprising:

    providing a third substrate, wherein a third LED epitaxial layer is arranged on the third substrate, and comprises a first doped semiconductor layer, an active layer and a second doped semiconductor layer which are stacked;

    bonding and connecting the second planarization layer and the third LED epitaxial layer through the third bonding layer;

    removing the third substrate and exposing the second doping type semiconductor layer of the third LED epitaxial layer;

    and etching the third LED epitaxial layer to form a plurality of third LED units.