Micro LED pixel and micro LED array panel

Abstract

A micro LED pixel includes an integrated circuit (IC) backplane, a plurality of light emitting diodes (LEDs), a plurality of light emitting diodes (LEDs), a plurality of light emitting diodes (LEDs), and a plurality of light emitting diodes (LEDs). The first light-emitting table top is arranged on the IC backboard; the second light-emitting table top is arranged above the first light-emitting table top, and a part of the second light-emitting table top does not cover the first light-emitting table top; the third light-emitting table top is arranged above the second light-emitting table top, and a part of the third light-emitting table top does not cover the first light-emitting table top or the second light-emitting table top; a first bottom electrical connection structure configured to connect a bottom surface of a portion of the second light emitting mesa and the IC backplane; a second bottom electrical connection structure configured to connect a bottom surface of a portion of the third light emitting mesa and the IC backplane; and an optical isolation structure disposed around at least a portion of the micro LED pixels.

Description

Technical Field

[0001] The present disclosure generally relates to microdisplay technology, and more particularly, to micro light emitting diodes (LEDs) and micro LED array panels. Background Art

[0002] Typically, a conventional micro LED pixel includes three or more micro LED mesas arranged in parallel to form a micro LED panel. The three or more micro LED mesas can emit light of different colors.

[0003] In order to reduce the volume of the micro LED pixel, the micro LED pixel may include a plurality of micro LED mesas formed vertically with a common central axis. The micro LED mesas define a light emitting area, and electrodes of the micro LED mesas are formed on an external panel outside the light emitting area of ​​the micro LED pixel. However, the external panel may increase the size of the micro LED pixel.

[0004] Therefore, the micro-LED pixel structure needs to be further improved to reduce its size and increase the light-emitting area. Summary of the invention

[0005] The embodiment of the present disclosure provides a micro LED pixel. The micro LED pixel includes: an integrated circuit (IC) backplane; a first light-emitting table disposed on the IC backplane; a second light-emitting table disposed above the first light-emitting table, a portion of the second light-emitting table not covering the first light-emitting table; a third light-emitting table disposed above the second light-emitting table, a portion of the third light-emitting table not covering the first light-emitting table or the second light-emitting table; a first bottom electrical connection structure configured to connect the bottom surface of a portion of the second light-emitting table to the IC backplane; a second bottom electrical connection structure configured to connect the bottom surface of a portion of the third light-emitting table to the IC backplane; and an optical isolation structure disposed around at least a portion of the micro LED pixel.

[0006] The embodiment of the present disclosure provides a micro LED array panel, which includes a plurality of micro LED pixels as described above, wherein the plurality of micro LED pixels are arranged in an array.

[0007] The embodiments of the present disclosure provide a micro LED array panel. The micro LED array panel includes a plurality of micro LED pixels, wherein the plurality of micro LED pixels are arranged in an array, and wherein the micro LED pixels further include a top conductive layer continuously formed on the top surface of a first light emitting mesa, on the top surface of a second light emitting mesa, and on the top surface of a third light emitting mesa, and the top conductive layers of the plurality of micro LED pixels are interconnected. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Embodiments and various aspects of the present disclosure are described in the following detailed description and accompanying drawings. The various features shown in the drawings are not drawn to scale.

[0009] Figure 1 A structural diagram of an exemplary micro LED pixel according to some embodiments of the present disclosure is shown.

[0010] Figure 2 Some embodiments according to the present disclosure are shown Figure 1 A top-down structural diagram of the micro LED pixel shown.

[0011] Figure 3 Some embodiments according to the present disclosure are shown Figure 2 The cross-sectional structure diagram of the micro LED pixel along the AA' direction is shown.

[0012] Figure 4 Some embodiments according to the present disclosure are shown Figure 2 The cross-sectional structure diagram of the micro LED pixel along the BB' direction is shown.

[0013] Figure 5 Some embodiments according to the present disclosure are shown Figure 2 The cross-sectional structure diagram of the micro LED pixel along the CC' direction is shown.

[0014] Figure 6 Some embodiments according to the present disclosure are shown Figure 2 The cross-sectional structure diagram of the micro LED pixel structure along the D-D' direction is shown.

[0015] Figure 7 A top view of an exemplary micro LED array panel according to some embodiments of the present disclosure is shown.

[0016] Figure 8 Some embodiments according to the present disclosure are shown Figure 7 Another top view of the exemplary micro LED array panel is shown with the top conductive layer and the top contact structure removed.

[0017] Fig. 9 Some embodiments according to the present disclosure are shown Figure 7 The cross-sectional structure diagram of the micro LED array panel along the EE' direction is shown.

[0018] Fig.10 Some embodiments according to the present disclosure are shown Figure 7 The cross-sectional structure diagram of the micro LED array panel along the FF' direction is shown.

[0019] Figures 11 to 17Top view structural diagrams of different exemplary micro LED pixels according to some embodiments of the present disclosure are respectively shown. DETAILED DESCRIPTION

[0020] Now specific reference will be made to the exemplary embodiments. Examples of these exemplary embodiments are shown in the accompanying drawings. The following description refers to the accompanying drawings, wherein, unless otherwise stated, the same numbers in different figures represent the same or similar elements. The implementations set forth in the following description of the exemplary embodiments do not represent all implementations consistent with the present invention. On the contrary, these implementations are only examples of devices and methods consistent with the aspects of the invention described in the attached claims. Specific aspects of the present disclosure are described in more detail below. If the terms and definitions provided herein conflict with the terms and / or definitions incorporated by reference, the terms and definitions provided herein shall prevail.

[0021] Embodiments of the present disclosure provide a micro LED pixel having staggered light emitting mesas to reduce one or more cross-sectional dimensions of the micro LED pixel.

[0022] Figure 1 FIG. 1 shows a structural diagram of an exemplary micro LED pixel 100 according to some embodiments of the present disclosure. Figure 1 As shown, the micro LED pixel 100 includes three light-emitting mesas that are spaced apart and staggered in the vertical direction. For example, a first light-emitting mesas 110 is disposed at the bottommost position, a second light-emitting mesas 120 is disposed above the first light-emitting mesas 110, and a third light-emitting mesas 130 is disposed above the second light-emitting mesas 120. The top surface of the first light-emitting mesas 110 is lower than the bottom surface of the second light-emitting mesas 120, and the top surface of the second light-emitting mesas 120 is lower than the bottom surface of the third light-emitting mesas 130. In other words, the first light-emitting mesas 110, the second light-emitting mesas 120, and the third light-emitting mesas 130 are spaced apart, that is, they do not contact each other.

[0023] As can be seen from the micro LED pixel 100 above, at least a portion of the three light emitting mesas may overlap. For example, at least a portion of the second light emitting mesas 120 covers, i.e., overlaps without contacting, at least a portion of the first light emitting mesas 110, or at least a portion of the third light emitting mesas 130 covers, i.e., overlaps without contacting, at least a portion of the first light emitting mesas 110 or at least a portion of the second light emitting mesas. At the same time, another portion of the second light emitting mesas 120 does not cover the first light emitting mesas 110, or another portion of the third light emitting mesas 130 does not cover the second light emitting mesas 120 or the first light emitting mesas 110. Figure 1In this embodiment, a portion of the third light-emitting mesa 130 covers a portion of the second light-emitting mesa 120, and a portion of the second light-emitting mesa 120 covers a portion of the first light-emitting mesa 110. Another portion of the first light-emitting mesa 110 is not covered by the second light-emitting mesa 120 or the third light-emitting mesa 130, and another portion of the second light-emitting mesa 120 is not covered by the third light-emitting mesa 130.

[0024] Each light-emitting mesa (i.e., 110, 120, and 130) includes a top electrode and a bottom electrode. For example, the top electrode is disposed at the top surface of the light-emitting mesa, and the bottom electrode is disposed at the bottom surface of the light-emitting mesa. In some embodiments, micro LED pixel 100 also includes a set of conductive bottom pads. Figure 1 As shown, a group of conductive bottom pads includes: a first bottom pad 111 of the first light-emitting mesa 110, which is disposed below the first light-emitting mesa 110; a second bottom pad 121 of the second light-emitting mesa 120, which is disposed below a portion of the second light-emitting mesa 120 that does not cover the first light-emitting mesa 110; and a third bottom pad 131 of the third light-emitting mesa 130, which is disposed below a portion of the third light-emitting mesa 130 that does not cover the second light-emitting mesa 120 or the first light-emitting mesa 110. That is, the second bottom pad 121 is disposed below a portion of the second light-emitting mesa 120 and is not covered by the first light-emitting mesa 110. The third bottom pad 131 is disposed below a portion of the third light-emitting mesa 130 and is not covered by the first light-emitting mesa 110 or the second light-emitting mesa 120. The first bottom pad 111, the second bottom pad 121, and the third bottom pad 131 do not contact each other. In some embodiments, the micro LED pixel 100 also includes an integrated circuit (IC) backplane ( Figure 1 The first bottom pad 111, the second bottom pad 121 and the third bottom pad 131 are each disposed on the IC backplane.

[0025] Therefore, each light-emitting mesa can be connected to the bottom pad under its own bottom surface. For the micro LED pixel 100, all bottom pads can be arranged under the light-emitting area formed by the first light-emitting mesa 110, the second light-emitting mesa 120 and the third light-emitting mesa 130. Therefore, the bottom pad does not require an external area, and because at least a portion of the three light-emitting mesas overlap, the cross-sectional size of the micro LED pixel 100 is reduced.

[0026] In some embodiments, the micro LED pixel 100 includes one or more bottom electrical connection structures for conductively connecting the bottom electrode on the bottom surface of the light-emitting mesa to the conductive bottom pad. For example, a first bottom electrical connection structure may be provided to connect the bottom surface of the first light-emitting mesa 110 to the first bottom pad 111. In this embodiment, since the first light-emitting mesa 110 is provided at the bottommost position, the first bottom electrical connection structure may be a bottom bonding layer or a bottom hole provided between the bottom surface of the first light-emitting mesa 110 and the first bottom pad 111 to connect the first light-emitting mesa 110 to the first bottom pad 111. A second bottom electrical connection structure 122 is provided to connect the bottom surface of the second light-emitting mesa 120 to the second bottom pad 121. A third bottom electrical connection structure 132 is provided to connect the bottom surface of the third light-emitting mesa 130 to the third bottom pad 131. In some embodiments, the second bottom electrical connection structure 122 and the third bottom electrical connection structure 132 are through holes. The through hole is made of metal and may have a hollow structure. The second bottom electrical connection structure 122 and the third bottom electrical connection structure 132 are not in a conductive contact state.

[0027] In some embodiments, each of the light-emitting mesas (i.e., 110, 120, and 130) has a conical structure, i.e., the top surface area of ​​the light-emitting mesas is smaller than the bottom surface area of ​​the light-emitting mesas, and each light-emitting mesas has a symmetrical structure. In some embodiments, the top surface is a rectangle having a width (shorter side) and a length (longer side). The symmetrical structure is characterized by a length vertical symmetry plane along the length direction and a width vertical symmetry plane along the width direction. The length vertical symmetry plane is perpendicular to the width vertical symmetry plane, and the intersection of the length vertical symmetry plane and the width vertical symmetry plane refers to the vertical center line of the light-emitting mesas perpendicular to it. In some embodiments, the top surface is a square, i.e., the width and length are equal. It can be understood that in this case, the width direction and the length direction can be interchanged, and can be referred to as the first direction and the second direction. Therefore, the length vertical symmetry plane and the width vertical symmetry plane can be interchanged, and are referred to as the first vertical symmetry plane and the second vertical symmetry plane.

[0028] Figure 2 Some embodiments according to the present disclosure are shown Figure 1 The top view of the micro LED pixel is shown in FIG. Figure 2 As shown, Figure 1 In this embodiment, the length vertical symmetry plane of the first light emitting mesa 110 is parallel to the length vertical symmetry plane of the third light emitting mesa 130 , and is perpendicular to the length vertical symmetry plane of the second light emitting mesa 120 .

[0029] Figures 3 to 6 An exemplary structure of a micro LED pixel 100 according to some embodiments of the present disclosure is shown.

[0030] Figure 3 Some embodiments according to the present disclosure are shown Figure 2 The cross-sectional structure diagram of the micro LED pixel 100 is taken along the AA′ direction. Figure 4 Some embodiments according to the present disclosure are shown Figure 2 The cross-sectional structure diagram of the micro LED pixel 100 along the BB′ direction is shown. Figure 5 Some embodiments according to the present disclosure are shown Figure 2 The cross-sectional structure diagram of the micro LED pixel 100 along the CC' direction is shown. Figure 6 Some embodiments according to the present disclosure are shown Figure 2 The cross-sectional structure diagram of the micro LED pixel 100 along the DD' direction is shown.

[0031] Reference Figures 3 to 6 , the micro LED pixel 100 further includes a top conductive layer 160 formed on the top surface of the micro LED pixel 100. Figure 3As shown, the top conductive layer 160 is continuously formed on the first light-emitting mesa 110, the second light-emitting mesa 120, and the third light-emitting mesa 130, and is configured to be connected to the top electrode of the first light-emitting mesa 110, the top electrode of the second light-emitting mesa 120, and the top electrode of the third light-emitting mesa 130. The top conductive layer 160 has a wavy structure and includes one or more recessed portions. In some embodiments, the top conductive layer 160 includes recessed portions (e.g., 161, 162, and 163) corresponding to each light-emitting mesa to be connected to each light-emitting mesa respectively. Since the three light-emitting mesas (i.e., 110, 120, and 130) are at different positions in the vertical direction, the depths of the three recessed portions (e.g., 161, 162, and 163) are different. In some embodiments, the micro LED pixel 100 also includes a top electrical connection structure (e.g., 113, 123, and 133) for connecting the top electrode of the light-emitting mesa to the top conductive layer 160. For example, a first top electrical connection structure 113 is provided on the top surface of the first light-emitting mesa 110 to connect to the top conductive layer 160. A second top electrical connection structure 123 is provided on the top surface of the second light-emitting mesa 120 to connect to the top conductive layer 160. The top electrical connection structures (e.g., 113, 123, and 133) may act as an ohmic contact layer. In some embodiments, the material of the top electrical connection structures (e.g., 113, 123, and 133) is a metal. In some embodiments, the top conductive layer 160 may directly contact the top surfaces of the three light-emitting mesas (i.e., 110, 120, and 130), so the top electrical connection structures (e.g., 113, 123, 133) are not required. In some embodiments, the top conductive layer 160 is transparent and has a light transmittance of not less than 70%. In some embodiments, the top conductive layer 160 is a TCO (transparent conductive oxide) layer, such as an ITO (indium tin oxide) layer, an AZO (antimony doped zinc oxide) layer, an ATO (antimony doped tin oxide) layer, a FTO (fluorine doped tin oxide) layer, or the like.

[0032] In some embodiments, a top contact structure 180 is disposed on the top conductive layer 160 and is configured to provide a contact for the top conductive layer 160. In some embodiments, the top contact structure 180 is connected to the top pad and is used to further connect to an external circuit. In some embodiments, the top pad is disposed on the IC backplane. In some embodiments, the top contact structure 180 is disposed at the edge of the micro LED pixel 100 and around the periphery of the micro LED pixel 100.

[0033] In some embodiments, the micro LED pixel 100 further includes an optical isolation structure 140 disposed around the micro LED pixel 100 and configured to prevent light from crossing between adjacent micro LED pixels. In some embodiments, the optical isolation structure 140 is selectively disposed around at least a portion of the micro LED pixel 100. Return Figure 2 The optical isolation structure 140 includes a first optical isolation structure 140A and a second optical isolation structure 140B. The first optical isolation structure 140A is disposed around the second light-emitting mesa 120, and the second optical isolation structure 140B is disposed on a side adjacent to the first light-emitting mesa 110 and opposite to the second light-emitting mesa 120.

[0034] from Figure 4 (showing a cross-sectional view along the BB' direction) and Figure 6 (Showing a cross-sectional view along the D-D' direction) It can be seen that the optical isolation structure 140 is not disposed at the side portion 210 around the third bottom electrical connection structure 132, or at the third bottom pad 131 where the side portion 210 is adjacent to other micro LED pixels. The optical isolation structure 140 is also not disposed at the side portion 220 of the first light-emitting mesa 110, where the side portion 220 is opposite to the third bottom electrical connection structure 132. As shown below with reference to Figure 8 As further described, the side portion 220 is adjacent to the third bottom pad 131 or the third bottom electrical connection structure 132 of the adjacent micro LED pixel. Figure 2 As shown, after removing the top conductive layer 160 and the top contact structure 180 , the IC backplate 190 may be exposed at the side portions 210 and 220 .

[0035] Reference Figure 4 Although the optical isolation structure 140 is not provided at the side portion 210 of the micro LED pixel 100, light crossover can be prevented by the optical isolation structure of the adjacent micro LED pixel or by the third bottom electrical connection structure 132. Figure 6 , although the optical isolation structure 140 is not provided at the side portions 210 and 220 of the micro LED pixel 100, light crossover can be prevented by the third bottom electrical connection structure 132. In these embodiments, the size of the third bottom electrical connection structure 132 can be as large as possible to provide better optical isolation. For example, the third bottom electrical connection structure 132 has a columnar structure, and the bottom surface of the third bottom electrical connection structure 132 is as large as the top surface of the third bottom pad 131.

[0036] In some embodiments, the bottom of the optical isolation structure 140 is equal to or lower than the bottom surface of the first light-emitting mesa 110. Therefore, the optical isolation structure 140 can prevent light from crossing between the light-emitting mesas of adjacent micro LED pixels. It can be understood that the optical isolation structure 140 is not connected to the light-emitting mesas (i.e., 110, 120, 130), the top conductive layer 160, and the IC backplane 190.

[0037] In some embodiments, optical isolation structure 140 is reflective. In some embodiments, the material of optical isolation structure 140 is metal.

[0038] In some embodiments, the top conductive layer 160 includes an edge recessed portion 164 around the third light emitting mesa 130. The bottom of the edge recessed portion 164 is as low as or lower than the bottom of the third light emitting mesa 130. The top contact structure 180 is disposed on the edge recessed portion 164. In some embodiments, the top contact structure 180 fills the edge recessed portion 164, and the material of the top contact structure 180 is metal. Therefore, the edge recessed portion 164 with the top contact structure 180 can provide optical isolation for light crossing from the third light emitting mesa 130 of the adjacent micro LED pixel. In this embodiment, as shown in FIG. Figure 4 and Figure 5 As shown, the top of the optical isolation structure 140 can be lower than the bottom of the third light-emitting mesa 130. That is, the top of the optical isolation structure 140 can be as low as or lower than the bottom of the third light-emitting mesa 130, and equal to or higher than the top of the second light-emitting mesa 120. In some embodiments, the top of such a portion of the optical isolation structure 140 is equal to or higher than the top of the second light-emitting mesa 120.

[0039] In some embodiments, the micro LED pixel 100 further includes a dielectric material 150 filled within the micro LED pixel 100, that is, the dielectric material 150 fills a space at least partially defined by the IC backplane 190, the top conductive layer 160, and the optical isolation structure 140. More specifically, the dielectric material 150 fills the first light emitting mesa 110, the second light emitting mesa 120, the third light emitting mesa 130, the second bottom electrical connection structure 122, the third bottom electrical connection structure 132, the first bottom pad 111, the second bottom pad 121, the third bottom pad 131, the IC backplane 190, the top conductive layer 160, and the space between the optical isolation structures 140A and 140B. In some embodiments, the space defined by the IC backplane 190, the top conductive layer 160, and the optical isolation structures 140A and 140B may have a box structure. In some embodiments, the dielectric material 150 is selected from one or more of silicon oxide, silicon nitride, SiCN, SiNO, or Al2O3. In some embodiments, dielectric material 150 is transparent.

[0040] With the above structure, the micro LED pixel provided by the embodiment of the present disclosure can have a good balance between high transmittance and size. Due to the staggered arrangement of the light-emitting mesas, a bottom connection structure can be provided under each light-emitting mesas, and at least a portion of the light-emitting mesas are overlapped. Therefore, an external panel for connecting to the electrode is not required, thereby reducing the cross-sectional size of the micro LED pixel with higher transmittance.

[0041] Figure 7 A top view of an exemplary micro LED array panel 700 according to some embodiments of the present disclosure is shown. Figure 8 Another top view of the micro LED array panel 700 according to some embodiments of the present disclosure is shown without the top conductive layer 160 and the top contact structure 180. Figure 7 and Figure 8 , the micro LED array panel 700 includes two or more micro LED pixels 100 arranged in an array. In this embodiment, a 3×2 array is described. Figure 2 As shown, the side portion 220 is adjacent to the third bottom pad 131 or the third bottom electrical connection structure 132 of the adjacent micro LED pixel. Figure 7 As shown, each micro LED pixel 100 may be rectangular in a top view, and thus two or more micro LED pixels 100 may be closely arranged.

[0042] Fig. 9 Some embodiments according to the present disclosure are shown Figure 7 The cross-sectional structure diagram of the micro LED array panel 700 is taken along the EE' direction. Fig.10 Some embodiments according to the present disclosure are shown Figure 7 The cross-sectional structure diagram of the micro LED array panel 700 along the FF' direction is shown. Fig. 9 and Fig.10 As shown, light crossover between adjacent micro LED pixels may be at least partially prevented by optical isolation structure 140 .

[0043] Reference Fig. 9 and Fig.10 In some implementations, the top conductive layers 160 of the plurality of micro LED pixels 100 are interconnected. For example, the top conductive layer 160 is continuously formed on the top of the micro LED array panel 700.

[0044] In some embodiments, the IC backplanes 190 of the plurality of micro LED pixels 100 are interconnected. For example, the IC backplane 190 may be continuously provided as the entire bottom plate of the micro LED array panel 700. In some embodiments, the entire IC backplane 190 further includes a top pad (not shown), and the top conductive layer 160 is connected to the top pad. In some embodiments, an external wire is also provided for connecting the top contact structure 180 to the top pad.

[0045] return Figure 1 In some embodiments, the first light-emitting mesa 110 is oriented along the first length direction D1, the second light-emitting mesa 120 is oriented along the second length direction D2, and the third light-emitting mesa 130 is oriented along the third length direction D3. In some embodiments, the vertical centerline of the third light-emitting mesa 130 is not aligned with the vertical centerline of the second light-emitting mesa 120. In this embodiment, the length vertical symmetry plane of the first light-emitting mesa 110 is parallel to the length vertical symmetry plane of the third light-emitting mesa 130, and both are perpendicular to the length vertical symmetry plane of the second light-emitting mesa 120.

[0046] Figures 11 to 17 The top view structures of different exemplary micro LED pixels according to various embodiments of the present disclosure are shown respectively. In such different embodiments, the first light emitting mesa 110, the second light emitting mesa 120 and the third light emitting mesa 130 can be arranged in different directions and have different sizes.

[0047] Reference Fig.11 ,and Figure 1 Consistent with the exemplary micro LED pixel shown, in the exemplary micro LED pixel 100A, the first vertical symmetry plane 110A of the first light emitting mesa 110 is parallel to the first vertical symmetry plane 130A of the third light emitting mesa 130 and perpendicular to the first vertical symmetry plane 120A of the second light emitting mesa 120. The second vertical symmetry plane 110B of the first light emitting mesa 110 is aligned with the second vertical symmetry plane 130B of the third light emitting mesa 130, that is, the second vertical symmetry plane 110B of the first light emitting mesa 110 is coplanar with the second vertical symmetry plane 130B of the third light emitting mesa 130. A portion of the third light emitting mesa 130 covers a portion of the second light emitting mesa 120, and a portion of the second light emitting mesa 120 covers a portion of the first light emitting mesa 110. Another portion of the first light emitting mesa is not covered by the second light emitting mesa 120 or the third light emitting mesa 130, and another portion of the second light emitting mesa 120 is not covered by the third light emitting mesa 130. In this embodiment, each light emitting mesa may have a light emitting area that faces upward and is not covered by other light emitting mesas. Therefore, the light emitting quality can be high and the transmittance of the light emitting mesa can be balanced.

[0048] Reference Fig.12 , in the exemplary micro LED pixel 100B, a portion of the second light emitting mesa 120 covers a portion of the first light emitting mesa 110, another portion of the second light emitting mesa 120 does not cover the first light emitting mesa 110, and another portion of the first light emitting mesa 110 is not covered by the second light emitting mesa 120. The third light emitting mesa 130 does not cover the second light emitting mesa 120 or the first light emitting mesa 110. In this embodiment, both the second light emitting mesa 120 and the third light emitting mesa 130 can emit light without being covered by the other light emitting mesa. More specifically, in Fig.12 , the first vertical symmetry plane 110A of the first light-emitting mesa 110 is parallel to the first vertical symmetry plane 130A of the third light-emitting mesa 130, and both are perpendicular to the first vertical symmetry plane 120A of the second light-emitting mesa 120. The second vertical symmetry plane 110B of the first light-emitting mesa 110 is aligned with the second vertical symmetry plane 130B of the third light-emitting mesa 130, that is, the second vertical symmetry plane 110B of the first light-emitting mesa 110 is coplanar with the second vertical symmetry plane 130B of the third light-emitting mesa 130. Since the third light-emitting mesa 130 does not cover the second light-emitting mesa 120 or the first light-emitting mesa 110, the third light-emitting mesa 130 can be arranged at any position in the vertical direction as long as the third light-emitting mesa 130 does not contact the first light-emitting mesa 110 or the second light-emitting mesa 120. For example, the third light-emitting mesa 130 and the second light-emitting mesa 120 can be arranged in the same plane. Therefore, the height of the micro LED pixel 100B can be reduced.

[0049] Reference Fig.13 , in the exemplary micro LED pixel 100C, the first light emitting mesa 110 is completely covered by a portion of the second light emitting mesa 120. Another portion of the second light emitting mesa 120 does not cover the first light emitting mesa 110. The third light emitting mesa 130 does not cover the second light emitting mesa 120 or the first light emitting mesa 110. More specifically, the first vertical symmetry plane 120A of the second light emitting mesa 120 is coplanar with the second vertical symmetry plane 110B of the first light emitting mesa 110, and is further parallel to the first vertical symmetry plane 130A of the third light emitting mesa 130. The second vertical symmetry plane 120B of the second light emitting mesa 120 is coplanar with the second vertical symmetry plane 130B of the third light emitting mesa 130, and is further parallel to the first vertical symmetry plane 110A of the first light emitting mesa 110. Since the third light-emitting mesa 130 does not cover the second light-emitting mesa 120 or the first light-emitting mesa 110, the third light-emitting mesa 130 can be disposed at any position in the vertical direction as long as the third light-emitting mesa 130 does not contact the first light-emitting mesa 110 or the second light-emitting mesa 120. For example, the third light-emitting mesa 130 and the second light-emitting mesa 120 can be disposed in the same plane. Therefore, the height of the micro LED pixel 100C can be reduced.

[0050] Reference Fig.14 , in the exemplary micro LED pixel 100D, the second light emitting mesa 120 is completely covered by a portion of the third light emitting mesa 130. Another portion of the third light emitting mesa 130 does not cover the second light emitting mesa 120. The first light emitting mesa 110 is not covered by the second light emitting mesa 120 or the third light emitting mesa 130. The first light emitting mesa 110 can emit light without being covered by the other light emitting mesa. More specifically, the first vertical symmetry plane 130A of the third light emitting mesa 130 is coplanar with the second vertical symmetry plane 120B of the second light emitting mesa 120, and is further parallel to the first vertical symmetry plane 110A of the first light emitting mesa 110. The second vertical symmetry plane 110B of the first light emitting mesa 110 is coplanar with the second vertical symmetry plane 130B of the third light emitting mesa 130, and is further parallel to the first vertical symmetry plane 120A of the second light emitting mesa 120. Since the first light-emitting mesa 110 is not covered by the second light-emitting mesa 120 or the third light-emitting mesa 130, the first light-emitting mesa 110 can be disposed at any position in the vertical direction as long as the first light-emitting mesa 110 does not contact the second light-emitting mesa 120 or the third light-emitting mesa 130. For example, the first light-emitting mesa 110 and the second light-emitting mesa 120 can be disposed in the same plane. Therefore, the height of the micro LED pixel 100D can be reduced.

[0051] Reference Fig.15 , in the exemplary micro LED pixel 100E, the second light emitting mesa 120 is completely covered by a portion of the third light emitting mesa 130, and a portion of the second light emitting mesa 120 covers a portion of the first light emitting mesa 110. A portion of the third light emitting mesa 130 also covers a portion of the first light emitting mesa 110. More specifically, a first vertical symmetry plane 130A of the third light emitting mesa 130 is coplanar with a second vertical symmetry plane 120B of the second light emitting mesa 120, and is further parallel to the first vertical symmetry plane 110A of the first light emitting mesa 110. The second vertical symmetry plane 110B of the first light emitting mesa 110 is coplanar with the second vertical symmetry plane 130B of the third light emitting mesa 130, and is further parallel to the first vertical symmetry plane 120A of the second light emitting mesa 120.

[0052] Reference Fig.16In the exemplary micro LED pixel 100F, the third light emitting mesa 130 does not cover any portion of the second light emitting mesa 120 or the first light emitting mesa 110. A portion of the second light emitting mesa 120 covers a portion of the first light emitting mesa 110. More specifically, a first vertical symmetry plane 110A of the first light emitting mesa 110 is parallel to the first vertical symmetry plane 130A of the third light emitting mesa 130, and is perpendicular to the first vertical symmetry plane 120A of the second light emitting mesa 120. A second vertical symmetry plane 110B of the first light emitting mesa 110 is parallel to the second vertical symmetry plane 130B of the third light emitting mesa 130, and is perpendicular to the second vertical symmetry plane 120B of the second light emitting mesa 120. Fig.12 Compared to the micro LED pixel 100B shown in FIG. 1 , in this embodiment, the emission area of ​​the third light emitting mesa 130 is reduced, and the emission area of ​​the first light emitting mesa 110 is increased. Since the third light emitting mesa 130 does not cover the second light emitting mesa 120 or the first light emitting mesa 110, the third light emitting mesa 130 can be arranged at any position in the vertical direction as long as the third light emitting mesa 130 does not contact the first light emitting mesa 110 or the second light emitting mesa 120. For example, the third light emitting mesa 130 and the second light emitting mesa 120 can be arranged in the same plane. Therefore, the height of the micro LED pixel 100F can be reduced.

[0053] Reference Fig.17 In the exemplary micro LED pixel 100G, a portion of the third light emitting mesa 130 covers a portion of the second light emitting mesa 120. The first light emitting mesa 110 is not covered by the second light emitting mesa 120 or the third light emitting mesa 130. More specifically, a first vertical symmetry plane 110A of the first light emitting mesa 110 is parallel to the first vertical symmetry plane 130A of the third light emitting mesa 130, and is perpendicular to the first vertical symmetry plane 120A of the second light emitting mesa 120. A second vertical symmetry plane 110B of the first light emitting mesa 110 is parallel to the second vertical symmetry plane 130B of the third light emitting mesa 130, and is perpendicular to the second vertical symmetry plane 120B of the second light emitting mesa 120. Fig.14 Compared to the micro LED pixel 100D shown, the emission area of ​​the first light emitting mesa 110 is reduced, while the emission area of ​​the second light emitting mesa 120 is increased. Fig.16Compared with the micro LED pixel 100F shown in FIG. 1 , the emission area of ​​the second light emitting mesa 120 is reduced, while the emission area of ​​the third light emitting mesa 130 is increased. Since the first light emitting mesa 110 is not covered by the second light emitting mesa 120 or the third light emitting mesa 130, the first light emitting mesa 110 can be arranged at any position in the vertical direction as long as the first light emitting mesa 110 does not contact the second light emitting mesa 120 or the third light emitting mesa 130. For example, the first light emitting mesa 110 and the second light emitting mesa 120 can be arranged in the same plane. Therefore, the height of the micro LED pixel 100G can be reduced.

[0054] In some embodiments, the top surface area of ​​the bottommost light-emitting mesa is the largest among the areas of the three or more light-emitting mesas. In this embodiment, the top surface area of ​​the first light-emitting mesa 110 is greater than the top surface area of ​​the second light-emitting mesa 120 and the top surface area of ​​the third light-emitting mesa 130.

[0055] In some embodiments, the three or more light-emitting mesas include at least a red-emitting mesas configured to emit red light, a green-emitting mesas configured to emit green light, and a blue-emitting mesas configured to emit blue light. For example, the first light-emitting mesas 110 is a red-emitting mesas, the second light-emitting mesas 120 is a green-emitting mesas, and the third light-emitting mesas 130 is a blue-emitting mesas. In some embodiments, the first light-emitting mesas 110 is a red-emitting mesas, the second light-emitting mesas 120 is a blue-emitting mesas, and the third light-emitting mesas 130 is a green-emitting mesas.

[0056] Those skilled in the art will appreciate that there are many other arrangements for these three or more light-emitting mesas. The purpose of these arrangements is that each light-emitting mesa can be connected to an electrode below the light-emitting mesa itself without the need for an external panel. Therefore, the cross-sectional size of the micro LED pixel can be reduced. In some embodiments, the arrangement of three or more light-emitting mesas forms a rectangular top surface. Therefore, the micro LED pixels provided by the embodiments of the present disclosure facilitate assembly of a micro LED array panel with a large light-emitting area.

[0057] It should be noted that relational terms such as "first" and "second" herein are used only to distinguish one entity or operation from another entity or operation, and do not require or imply any actual relationship or order between these entities or operations. In addition, the words "include", "have", "include" and "contain" and other similar forms are intended to be equivalent in meaning and are open-ended, and one or more items following any of these words are not intended to be an exhaustive list of such one or more items, or are not intended to be limited to the listed one or more items.

[0058] Unless otherwise specifically stated, the term "or" as used herein includes all possible combinations, except where not feasible. For example, if it is stated that a database may include A or B, then, unless otherwise specifically stated or not feasible, the database may include A, or B, or A and B. A second example is that if it is stated that a database may include A, B, or C, then, unless otherwise specifically stated or not feasible, the database may include A, or B, or C, or A and B, or A and C, or B and C, or A, B, and C.

[0059] In the foregoing description, embodiments have been described with reference to many specific details, which may vary depending on the implementation. Certain adjustments and modifications may be made to the described embodiments. In view of the description and practice of the invention disclosed herein, other embodiments may be apparent to those skilled in the art. It is intended that the description and embodiments are only to be regarded as exemplary, and the following claims indicate the true scope and spirit of the invention. It is also intended that the order of the steps shown in the figures is for illustrative purposes only and is not intended to be limited to any particular order of steps. Therefore, it will be appreciated by those skilled in the art that these steps may be performed in different orders when implementing the same method.

[0060] In the drawings and the specification, exemplary embodiments have been disclosed. However, many changes and modifications may be made to these embodiments. Therefore, although specific terms are used, they are used only in a general and descriptive sense and not for the purpose of limitation.

Claims

1. A micro LED pixel, characterized in that: include: Integrated Circuit (IC) backplane; A first light-emitting table is arranged on the IC back plate; A second light-emitting mesa is disposed above the first light-emitting mesa, and a portion of the second light-emitting mesa does not cover the first light-emitting mesa; A third light-emitting mesa is disposed above the second light-emitting mesa, and a portion of the third light-emitting mesa does not cover the first light-emitting mesa or the second light-emitting mesa; a first bottom electrical connection structure configured to connect a bottom surface of the portion of the second light-emitting mesa to the IC backplane; a second bottom electrical connection structure configured to connect a bottom surface of the portion of the third light-emitting mesa to the IC backplane; as well as An optical isolation structure is disposed around at least a portion of the micro LED pixel.

2. The micro LED pixel according to claim 1, characterized in that: The optical isolation structure includes: a first optical isolation structure disposed around a portion of the second light emitting mesa; and a second optical isolation structure disposed on a side adjacent to the first light emitting mesa and opposite to the second light emitting mesa.

3. The micro LED pixel according to claim 1, characterized in that: The optical isolation structure is not disposed on the peripheral side of the second bottom electrical connection structure.

4. The micro LED pixel according to claim 3, characterized in that: The optical isolation structure is not disposed at a portion of a side surface of the first light emitting mesa, wherein the side surface is opposite to the second bottom electrical connection structure.

5. The micro LED pixel according to claim 1, characterized in that: The present invention also includes a top conductive layer, which is continuously formed on the top surface of the first light-emitting mesa, the top surface of the second light-emitting mesa, and the top surface of the third light-emitting mesa, and is configured to be connected to the top electrode of the first light-emitting mesa, the top electrode of the second light-emitting mesa, and the top electrode of the third light-emitting mesa.

6. The micro LED pixel according to claim 5, characterized in that: The top conductive layer includes one or more recessed portions for respectively connecting to the top electrode of the first light emitting mesa, the top electrode of the second light emitting mesa, and the top electrode of the third light emitting mesa.

7. The micro LED pixel according to claim 5, characterized in that: The top conductive layer is transparent and has a light transmittance of not less than 70%.

8. The micro LED pixel according to claim 6, characterized in that: The top conductive layer further includes an edge recessed portion adjacent to the third light emitting mesa, wherein a bottom of the edge recessed portion is lower than a top of the third light emitting mesa.

9. The micro LED pixel according to claim 8, characterized in that: Also included is a top contact structure disposed on the top conductive layer and configured to provide a contact for the top conductive layer.

10. The micro LED pixel according to claim 9, characterized in that: The top contact structure is filled in the edge recessed portion.

11. The micro LED pixel according to claim 10, characterized in that: The material of the top contact structure is metal.

12. The micro LED pixel according to claim 11, characterized in that: The top of the optical isolation structure is equal to or higher than the top of the second light-emitting mesa and equal to or lower than the bottom of the third light-emitting mesa.

13. The micro LED pixel according to claim 11, characterized in that: The top contact structure is reflective.

14. The micro LED pixel according to claim 5, characterized in that: The optical isolation structure does not contact the top conductive layer, the first light emitting mesa, the second light emitting mesa, the third light emitting mesa, the bottom pad, or the IC backplane.

15. The micro LED pixel according to claim 14, characterized in that: The optical isolation structure is reflective.

16. The micro LED pixel according to claim 14, characterized in that: The material of the optical isolation structure is metal.

17. The micro LED pixel according to claim 5, characterized in that: Also included is a dielectric material filling the space within the micro LED pixel.

18. The micro LED pixel according to claim 17, characterized in that: The dielectric material is selected from one of silicon oxide, silicon nitride, SiCN, SiNO or Al2O3.

19. The micro LED pixel according to claim 18, characterized in that: The dielectric material is transparent.

20. The micro LED pixel according to claim 1, characterized in that: The first bottom electrical connection structure is not connected to the second bottom electrical connection structure.

21. The micro LED pixel according to claim 1, characterized in that: The IC backplane includes a first bottom pad, a second bottom pad, and a third bottom pad, each of which is disposed on the IC backplane and is configured to be connected to a bottom electrode of the first light-emitting mesa, a bottom electrode of the second light-emitting mesa, and a bottom electrode of the third light-emitting mesa, respectively; and The micro LED pixel further includes a third bottom electrical connection structure for connecting the first light emitting mesa to the first bottom pad of the IC backplane, wherein the third bottom electrical connection structure is a bonding layer or a bottom hole.

22. The micro LED pixel according to claim 21, characterized in that: The first bottom electrical connection structure is bonded to the second bottom pad of the IC backplane.

23. The micro LED pixel according to claim 22, characterized in that: The second bottom electrical connection structure is bonded to the third bottom pad of the IC backplane.

24. The micro LED pixel according to claim 1, characterized in that: The first light emitting mesa is not covered by any portion of the third light emitting mesa.

25. The micro LED pixel according to claim 1, characterized in that: At least a portion of the second light emitting mesa covers at least a portion of the first light emitting mesa.

26. The micro LED pixel according to claim 1, characterized in that: At least a portion of the third light-emitting mesa covers at least a portion of the first light-emitting mesa or at least a portion of the second light-emitting mesa.

27. The micro LED pixel according to claim 1, characterized in that: Each of the first light-emitting mesa, the second light-emitting mesa, and the third light-emitting mesa has a symmetrical structure, and the symmetrical structure has: a first vertical plane of symmetry along the length direction; a second vertical plane of symmetry along the width direction; and A vertical center line, wherein the vertical center line is an intersection line of the first vertical symmetry plane and the second vertical symmetry plane.

28. The micro LED pixel according to claim 27, characterized in that: The vertical center line of the third light emitting mesa is not aligned with the vertical center line of the second light emitting mesa.

29. The micro LED pixel according to claim 27, characterized in that: The first vertical symmetry plane and the second vertical symmetry plane of the third light-emitting mesa are not coplanar with the first vertical symmetry plane and the second vertical symmetry plane of the second light-emitting mesa.

30. The micro LED pixel according to claim 29, characterized in that: The first vertical symmetry plane of the third light-emitting mesa is parallel to the first vertical symmetry plane of the second light-emitting mesa.

31. The micro LED pixel according to claim 27, characterized in that: The first vertical symmetry plane of the third light-emitting mesa is coplanar with the first vertical symmetry plane of the second light-emitting mesa.

32. The micro LED pixel according to claim 27, characterized in that: The top surface of the first light-emitting mesa, the top surface of the second light-emitting mesa, and the top surface of the third light-emitting mesa are rectangular.

33. The micro LED pixel according to claim 1, characterized in that: The top surface area of ​​the first light-emitting mesa is larger than the top surface area of ​​the second light-emitting mesa and larger than the top surface area of ​​the third light-emitting mesa.

34. The micro LED pixel according to claim 1, characterized in that: The first light emitting mesa is configured to emit red light, the second light emitting mesa is configured to emit green light, and the third light emitting mesa is configured to emit blue light.

35. The micro LED pixel according to claim 1, characterized in that: The first light emitting mesa is configured to emit red light, the second light emitting mesa is configured to emit blue light, and the third light emitting mesa is configured to emit green light.

36. A micro LED array panel, characterized in that: include: A plurality of micro LED pixels according to any one of claims 1 to 35, wherein the plurality of micro LED pixels are arranged in an array.

37. The micro LED array panel according to claim 36, characterized in that: The IC backplanes of the plurality of micro LED pixels are interconnected.

38. A micro LED array panel, characterized in that: include: A plurality of micro LED pixels according to any one of claims 1 to 4 and 20 to 35, wherein the plurality of micro LED pixels are arranged in an array; and The micro LED pixel further includes a top conductive layer continuously formed on the top surface of the first light emitting mesa, the top surface of the second light emitting mesa, and the top conductive layer of each of the plurality of micro LED pixels are interconnected.

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