CN219163403U - Micro LED device and display apparatus including the same - Google Patents

Abstract

The present disclosure provides a micro LED device and a display apparatus including the same. The micro LED device includes: a driving substrate; the micro LED chip array is flip-chip bonded on the driving substrate, and comprises a mesa structure, wherein the mesa structure comprises at least two bosses, and each boss in the at least two bosses is provided with a plurality of light emitting units. According to this scheme, the stability of the micro LED device can be improved and the electrical performance of the device can be improved.

Description

Micro LED device and display apparatus including the same

Technical Field

The disclosure relates to the technical field of semiconductor LEDs, in particular to a micro LED device and a display device comprising the micro LED device.

Background

Micro-LED is a luminous semiconductor element with the size smaller than 50um, and has the advantages of low power consumption, long service life, high brightness, high contrast ratio and the like. With the progressive development of display technology, micro-LED technology has gradually become a trend of new display technology. However, micro-LEDs have problems of poor stability and poor electrical properties.

Disclosure of Invention

In order to solve the technical problems mentioned in the background art, the scheme of the present disclosure provides a micro LED device and a display apparatus including the same.

According to an aspect of the embodiments of the present disclosure, there is provided a micro LED device, wherein the micro LED device includes: a driving substrate; the micro LED chip array is flip-chip bonded on the driving substrate, and comprises a mesa structure, wherein the mesa structure comprises at least two bosses, and each boss in the at least two bosses is provided with a plurality of light emitting units.

Further, the micro LED chip array includes a first semiconductor layer, a quantum well structure, and a second semiconductor layer in order from bottom to top, and each of the at least two bosses includes a first semiconductor layer, a quantum well structure, and a second semiconductor layer in order.

Further, at least one group of light emitting units is arranged on each boss, and the number of the light emitting units in each group of light emitting units is 3 or more.

Further, a color quantum sheet is arranged above the at least one group of light-emitting units, at least one group of color quantum dots corresponding to the at least one group of light-emitting units are arranged on the color quantum sheet, and each group of color quantum dots comprises quantum dots with 2 or more colors.

Further, the light emitting units of each group of light emitting units emit light of different colors, so that each group of light emitting units forms white light.

Further, the micro LED chip array further includes: an insulating layer disposed on the mesa structure and including a contact hole exposing a portion of the first semiconductor layer and a portion of the second semiconductor layer on the at least two bosses, wherein a plurality of contact holes are opened on the insulating layer over each of the at least two bosses for forming a plurality of light emitting cells; a metal layer disposed on the exposed portion of the first semiconductor layer and the portion of the second semiconductor layer; and a metal block disposed on the metal layer.

Further, the insulating layer is provided with a plurality of first contact holes and a plurality of second contact holes, each of the plurality of first contact holes exposes a portion of the first semiconductor layer and each of the plurality of second contact holes exposes a portion of the second semiconductor layer on the boss, wherein the plurality of second contact holes are provided according to a preset contact hole size and a preset inter-hole size.

Further, the micro LED chip array further includes a current spreading layer disposed on the exposed portion of the first semiconductor layer and the portion of the second semiconductor layer, and the metal layer is disposed on the current spreading layer.

Further, the current spreading layer comprises an indium tin oxide layer.

Further, the substrate is a sapphire substrate, the first semiconductor layer is an N-GaN layer, the second semiconductor layer is a P-GaN layer, and the third semiconductor layer is a U-GaN layer.

Further, a color quantum sheet is provided on the surface of the third semiconductor layer.

According to another aspect of the embodiments of the present disclosure, there is also provided a display device. The display device comprises the micro LED device and a packaging assembly for packaging the micro LED device.

Further, the packaging component is provided with a color quantum sheet.

By the technical scheme, the mesa structure comprising at least two bosses can be formed, and a plurality of light-emitting units can be formed on each boss, so that the number of bosses and the number of light-emitting units on each boss are controlled, the overlarge total side area of the boss caused by the overlarge bosses can be improved, the stability of the device is further improved, the overlarge leakage current caused by the overlarge boss area can be improved, and the electrical performance of the device is further improved.

Drawings

The above, as well as additional purposes, features, and advantages of exemplary embodiments of the present disclosure will become readily apparent from the following detailed description when read in conjunction with the accompanying drawings. Several embodiments of the present disclosure are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar or corresponding parts and in which:

fig. 1 is a schematic side view illustrating a micro LED device according to one embodiment of the present disclosure;

FIG. 2 is a schematic side view illustrating an array of micro LEDs included in a micro LED device according to one embodiment of the present disclosure;

fig. 3 is a schematic top view illustrating a correspondence of bosses and light emitting units in a micro LED device according to one embodiment of the present disclosure;

fig. 4 is a schematic top view illustrating a correspondence between a boss provided with a color quantum sheet and a light emitting unit in a micro LED device according to an embodiment of the present disclosure;

fig. 5 is a schematic diagram illustrating a color quantum sheet disposed on a package assembly over a micro LED device in a display apparatus according to one embodiment of the present disclosure.

Detailed Description

It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other. The present disclosure will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present application. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

Spatially relative terms, such as "above … …," "above … …," "upper surface at … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial location relative to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "over" other devices or structures would then be oriented "below" or "beneath" the other devices or structures. Thus, the exemplary term "above … …" may include both orientations of "above … …" and "below … …". The device may also be oriented 90 degrees or at other orientations and the spatially relative descriptors used herein interpreted accordingly.

Exemplary embodiments according to the present disclosure will now be described in more detail with reference to the accompanying drawings. These exemplary embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. It should be appreciated that these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of these exemplary embodiments to those skilled in the art, that in the drawings, thicknesses of layers and regions are exaggerated for clarity, and identical reference numerals are used to denote identical devices, and thus descriptions thereof will be omitted.

The present disclosure provides a micro LED device. Referring to fig. 1 and 2, fig. 1 is a side view schematic diagram illustrating a micro LED device according to one embodiment of the present disclosure, and fig. 2 is a side view schematic diagram illustrating a micro LED array included in the micro LED device according to one embodiment of the present disclosure. Fig. 3 is a schematic top view illustrating a correspondence relationship of a boss and a light emitting unit in a micro LED device according to one embodiment of the present disclosure. Fig. 4 is a schematic top view illustrating a correspondence relationship between a boss provided with a color quantum sheet and a light emitting unit in a micro LED device according to an embodiment of the present disclosure. Fig. 5 is a schematic diagram illustrating a color quantum sheet disposed on a package assembly over a micro LED device in a display apparatus according to one embodiment of the present disclosure.

According to an embodiment of the present disclosure, referring to fig. 1 to 4, the micro LED device 1 includes: a drive substrate 20; a micro LED chip array 10 flip-chip bonded on the driving substrate 20, and the micro LED chip array 10 includes a mesa structure including at least two bosses 11 each of which is provided with a plurality of light emitting units 111. It should be understood that, for the sake of brevity and clarity of the drawings, fig. 1 and 2 schematically illustrate only one boss, and are not intended to limit the number of bosses.

The micro LED chip array may include a first semiconductor layer, a quantum well structure, and a second semiconductor layer in this order from bottom to top. As shown in fig. 2, the micro LED chip array 10 may include a substrate 101, a buffer layer 102, a third semiconductor layer 103, a first semiconductor layer 104, a quantum well structure 105, and a second semiconductor layer 106 in order from bottom to top. Each of the at least two bosses 11 may include a first semiconductor layer 104, a quantum well structure 105, and a second semiconductor layer 106 in order from bottom to top.

In one embodiment of the present disclosure, as shown in fig. 3, at least one group of light emitting units is provided on each boss 11, and the number of light emitting units 111 in each group of light emitting units is 3. Taking one boss 11 provided with a group of light emitting units as an example, one boss 11 corresponds to three light emitting units 111, and three light emitting units on each boss constitute one pixel, and each light emitting unit serves as one sub-pixel of the pixel.

In one embodiment of the present disclosure, at least one group of light emitting units is provided on each boss 11, and the number of light emitting units 111 in each group of light emitting units is 4 or more. Taking a group of light emitting units, for example, 4 light emitting units 111 in the group of light emitting units, are arranged on one boss 11, one boss 11 corresponds to four light emitting units 111, and four light emitting units on each boss form a pixel, and each light emitting unit serves as a sub-pixel of the pixel.

Thus, the sub-pixels of three colors of red, green and blue or other sub-pixels capable of synthesizing to obtain white light can be conveniently arranged, so that a group of sub-pixels capable of obtaining the color combination of the white light can be arranged on one boss to form the pixel of the white light. In implementation, in the case that the light emitting unit emits blue light, quantum dots of 2 colors (red quantum dots and green quantum dots) may be provided to obtain red, green, and blue sub-pixels. It is noted that fig. 3 schematically shows only 3 groups of light emitting units, and is not intended herein as a limitation on the number of groups of light emitting units.

In one embodiment of the present disclosure, as shown in fig. 4 in combination with fig. 3, a color quantum sheet is disposed above the at least one group of light emitting units, and at least one group of color quantum dots 1111 corresponding to the at least one group of light emitting units are disposed on the color quantum sheet, and each group of color quantum dots includes quantum dots of 2 or more colors. Specifically, the color quantum sheet may be disposed on the substrate 101 of the micro LED chip array 10 inversely bonded on the driving substrate 20, or the substrate 101 and the buffer layer 102 may be removed and directly disposed on the exposed third semiconductor layer 103. The color quantum dots on the color quantum sheet may correspond to light emitting units, and one group of color quantum dots corresponds to one group of light emitting units, so that each group of 3 light emitting units may be used as, for example, three sub-pixels of red, green and blue, respectively. The color quantum sheet arranged in this way can be matched with the light-emitting unit better, and a good photo-excitation effect is achieved.

In one embodiment of the present disclosure, the light emitting units of each group of light emitting units emit light of different colors such that each group of light emitting units forms white light. The self-luminescence of the luminous unit arranged in this way can reduce the arrangement of the color quantum sheet, thereby facilitating the preparation of the device. In addition, white light directly formed by light emitted by each group of light-emitting units can improve the light-emitting efficiency because the light does not pass through a quantum dot isochromatic conversion mode.

According to an embodiment of the present disclosure, as shown in fig. 1 and 2, the micro LED chip array 10 may further include: an insulating layer 107 disposed on the mesa structure and including a contact hole for exposing a portion of the first semiconductor layer 104 and a portion of the second semiconductor layer 106 on the at least two bosses 11, wherein a plurality of contact holes are opened on the insulating layer over each of the at least two bosses for forming a plurality of light emitting cells; a metal layer 109 disposed on the exposed portion of the first semiconductor layer 104 and the portion of the second semiconductor layer 106; a metal block 110 disposed on the metal layer 109. It is noted that the number of contact holes on the insulating layer over each boss corresponds to the number of light emitting cells on each boss. Preferably, the insulating layer may be a matting layer or a passivation layer, wherein the material of the matting layer may be a matting material such as a dark colored resist of black or a non-metallic layer.

In one embodiment of the present disclosure, the insulating layer 107 may be provided with a plurality of first contact holes 1071 and a plurality of second contact holes 1072, each of the plurality of first contact holes 1071 exposing a portion of the first semiconductor layer 104 and each of the plurality of second contact holes 1072 exposing a portion of the second semiconductor layer 106 on the boss, wherein the plurality of second contact holes 1072 are provided according to a preset contact hole size and a preset inter-hole size.

In this embodiment, when a plurality of second contact holes are formed in the insulating layer, the size of the second contact holes to be formed may be determined according to the size of the contact holes set in advance, and the distance between the second contact holes may be determined according to the size between the holes set in advance, thereby obtaining a second contact hole matrix meeting the requirements on each boss. Therefore, the aperture ratio of the micro LED device can be increased, and the optical crosstalk phenomenon caused by current expansion of the electrode arranged in the second contact hole can be improved.

It is noted that the number of contact holes shown in fig. 2 is only illustrative, and in particular, the number of second contact holes 1072 may be determined according to the number of light emitting units required. In addition, in the case where the mesa structure includes a plurality of bosses, each of the bosses is provided with the insulating layer and the second contact holes as described above, and thus, the number of bosses and the number of second contact holes on the bosses may be determined according to the number of light emitting units required.

In one embodiment of the present disclosure, the micro LED chip array 10 may further include a current spreading layer 108, the current spreading layer 108 being disposed on the exposed portions of the first semiconductor layer 104 and the second semiconductor layer 106, and the metal layer 109 being disposed on the current spreading layer 108. Preferably, the current spreading layer may include an indium tin oxide layer. The light-emitting efficiency can be improved by arranging the current expansion layer.

In some embodiments of the present disclosure, the substrate 101 may be a sapphire substrate, the first semiconductor layer 104 may be an N-GaN layer, the second semiconductor layer 106 may be a P-GaN layer, and the third semiconductor layer 103 may be a U-GaN layer.

In one embodiment of the present disclosure, the metal bumps are used to form metal bumps by reflow so that the micro LED chip array is flip-chip bonded on the driving substrate. The material of the metal block may comprise indium, which has a low melting point, and is particularly suitable for flip-chip bonding at a relatively low temperature, but may also comprise any suitable metal.

It should be noted that there are two types of structures in the related art: one is a Mesa structure in which a Mesa structure includes a large number of bosses each of which is formed with a light emitting unit, the bosses being realized by a dry etching technique such as ICP which causes the etching direction surface (boss side surface) to remain, and the contact surface to be uneven, whereby the side surfaces of the large number of bosses are made to be such that stability of the device is affected; another is the F-Mesa structure, in which the Mesa structure includes a boss, and a plurality of light emitting units are formed on the boss, which may cause a larger leakage current due to an excessively large surface area of the boss, thereby affecting the electrical performance of the device. According to the technical scheme of the disclosure, the mesa structure comprising at least two bosses can be formed, and a plurality of light-emitting units can be formed on each boss, so that the number of bosses and the number of light-emitting units on each boss are controlled, the overlarge total side area of the boss caused by the overlarge bosses is avoided, the stability of the device is further improved, the overlarge leakage current caused by the overlarge boss area is avoided, and the electrical performance of the device is further improved.

The disclosure also provides a display device. The display device comprises the micro LED device and a packaging assembly for packaging the micro LED device. Wherein the packaging component is provided with a color quantum sheet. As shown in fig. 5, the display apparatus 2 includes a micro LED device 1 and a package assembly including a package cover 21 including an opening 211 for exposing the light emitting unit 111, on which a color quantum sheet 22 may be disposed.

The display device can be applied to electronic equipment to realize technologies such as augmented Reality (Augmented Reality, AR), virtual Reality (VR), extended Reality (XR), mixed Reality (MR) and the like. For example, the Display device may be a projection portion of an electronic apparatus, such as a projector, head Up Display (HUD), or the like; for another example, the display device may be a display portion of an electronic apparatus, and for example, the electronic apparatus may include: smart phones, smart watches, notebook computers, tablet computers, automobile recorders, navigator, head-mounted devices, and any device having a display screen.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.

It should be noted that the terms "first," "second," and the like in the description and claims of the present application and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that embodiments of the present application described herein may be capable of being practiced otherwise than as specifically illustrated and described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The foregoing description of the preferred embodiments of the present disclosure is provided only and not intended to limit the disclosure so that various modifications and changes may be made to the present disclosure by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure should be included in the protection scope of the present disclosure.

Claims (10)

1. A micro LED device, wherein the micro LED device comprises:

a driving substrate;

the micro LED chip array is flip-chip bonded on the driving substrate, and comprises a mesa structure, wherein the mesa structure comprises at least two bosses, and each boss in the at least two bosses is provided with a plurality of light emitting units.

2. The micro LED device of claim 1, wherein the array of micro LED chips comprises, in order from bottom to top, a first semiconductor layer, a quantum well structure, and a second semiconductor layer, and each of the at least two bosses comprises, in order, a first semiconductor layer, a quantum well structure, and a second semiconductor layer.

3. The micro LED device of claim 1, wherein at least one group of light emitting units is provided on each boss, and the number of light emitting units in each group of light emitting units is 3 or more.

4. The micro LED device of claim 3, wherein a color quantum sheet is disposed over the at least one group of light emitting units, and at least one group of color quantum dots corresponding to the at least one group of light emitting units is disposed on the color quantum sheet, each group of color quantum dots comprising quantum dots of 2 or more colors.

5. The micro LED device of claim 3, wherein the light emitting units of each group of light emitting units emit light of different colors such that each group of light emitting units forms white light.

6. The micro LED device of claim 2, wherein the array of micro LED chips further comprises:

an insulating layer disposed on the mesa structure and including a contact hole exposing a portion of the first semiconductor layer and a portion of the second semiconductor layer on the at least two bosses, wherein a plurality of contact holes are opened on the insulating layer over each of the at least two bosses for forming a plurality of light emitting cells;

a metal layer disposed on the exposed portion of the first semiconductor layer and the portion of the second semiconductor layer;

and a metal block disposed on the metal layer.

7. The micro LED device of claim 6, wherein the insulating layer is provided with a plurality of first contact holes and a plurality of second contact holes, each of the plurality of first contact holes exposing a portion of the first semiconductor layer and each of the plurality of second contact holes exposing a portion of the second semiconductor layer on the boss, wherein the plurality of second contact holes are provided according to a preset contact hole size and a preset inter-hole size.

8. The micro LED device of claim 6, wherein the array of micro LED chips further comprises a current spreading layer disposed on the exposed portions of the first semiconductor layer and the portions of the second semiconductor layer, and the metal layer is disposed on the current spreading layer.

9. A display apparatus, wherein the display apparatus comprises the micro LED device of any one of claims 1 to 8 and a package assembly for packaging the micro LED device.

10. The display device of claim 9, wherein the package assembly has a color quantum sheet disposed thereon.

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