TWI647831B - Micro light emitting device and manufacturing method thereof - Google Patents

Abstract

A method for fabricating a miniature light emitting diode device. A plurality of first type epitaxial structures are formed on the first substrate, and the first type epitaxial structures are separated from each other. The first type epitaxial structure and the first substrate have a first connecting layer and a first adhesive layer. The first connection layer connects the first type epitaxial structures, and the first adhesive layer is located between the first connection layer and the first substrate. The Young's modulus of the first tie layer is greater than the Young's modulus of the first adhesive layer. The first connection layer between any two adjacent first type epitaxial structures is removed to form a plurality of first connections separated from each other. Each of the first connecting portions is respectively connected to a corresponding first type epitaxial structure.

Description

Miniature light emitting diode device and manufacturing method thereof

The present invention relates to a light-emitting device and a method of fabricating the same, and more particularly to a miniature light-emitting diode device and a method of fabricating the same.

The fabrication steps of the conventional micro-light-emitting diode device are as follows: First, a plurality of epitaxial structures are formed on the grown substrate, and desired electrodes are formed on the respective epitaxial structures. A first adhesive layer is formed on the growth substrate to coat the respective epitaxial structures and their electrodes. Next, the first substrate is bonded to the first adhesive layer, and the grown substrate is removed. At this time, the relative positions of the epitaxial structures to each other are fixed by the first adhesive layer. Then, the second substrate is adhered to the epitaxial structure and the first adhesive layer through the second adhesive layer. Finally, these epitaxial structures are transferred to the wiring substrate.

In the process of bonding the second substrate through the second adhesive layer to the first adhesive layer, the second adhesive layer is heated and the second substrate and the second adhesive layer are pressurized. At this time, the heated or stressed first adhesive layer generates a flow and impacts the epitaxial structures, so that the relative positions of the epitaxial structures are shifted from each other. That is to say, when transferring the epitaxial structures onto the circuit substrate, the defects generated in the above manufacturing steps may cause the electrodes on the respective epitaxial structures to be inaccurately aligned to the electrical contacts on the circuit substrate. This in turn affects process efficiency, process yield, and product reliability.

The present invention provides a miniature light emitting diode device that has good reliability.

The invention provides a method for fabricating a miniature light-emitting diode device, which can improve process efficiency and process yield.

A method of fabricating a miniature light-emitting diode device of the present invention includes the following fabrication steps. (a) forming a plurality of first type epitaxial structures on the first substrate, and the first type of epitaxial structures are separated from each other, wherein the first type of epitaxial structure and the first substrate have a first connecting layer and a first An adhesive layer. The first connecting layer connects the first type epitaxial structures, and the first adhesive layer is located between the first connecting layer and the first substrate, wherein a Young's modulus of the first connecting layer is greater than a Young's modulus of the first adhesive layer . (b) removing the first connection layer between any two adjacent first type epitaxial structures to form a plurality of first connections separated from each other, wherein each of the first connections is associated with a corresponding first type The epitaxial structures are connected.

In an embodiment of the invention, the method for fabricating the micro-light-emitting diode device further includes: (c) electrically bonding a portion of the first-type epitaxial structure to the target substrate.

In an embodiment of the invention, the method for fabricating the micro-light-emitting diode device further includes: (d) forming a plurality of second-type epitaxial structures on the second substrate, and the second-type epitaxial structures Separating from each other, wherein the second type epitaxial structure and the second substrate have a second connecting layer and a second adhesive layer. The second connecting layer connects the second type epitaxial structures, and the second adhesive layer is located between the second connecting layer and the second substrate, wherein the Young's modulus of the second connecting layer is greater than the Young's modulus of the second adhesive layer . (e) removing a second connection layer between any two adjacent second type epitaxial structures to form a plurality of second connections separated from each other, wherein each of the second connections is associated with a corresponding second type The epitaxial structures are connected.

In an embodiment of the invention, the method for fabricating the micro-light-emitting diode device further includes: (f) electrically bonding a portion of the first-type epitaxial structure of step (b) to the target substrate. (g) electrically bonding a portion of the second type epitaxial structure of step (e) to the target substrate.

In an embodiment of the invention, the total thickness of each of the first type epitaxial structures and the corresponding first connecting portions is less than or equal to the total thickness of each of the second type epitaxial structures and the corresponding second connecting portion.

In an embodiment of the invention, the ratio of the thickness of each of the first connecting portions to the thickness of the corresponding first type of epitaxial structure is greater than 0.01 and less than or equal to 0.5.

In an embodiment of the invention, the ratio of the thickness of each of the first connection layers to the side length of the corresponding first type of epitaxial structure is greater than 0.001 and less than or equal to 0.3.

In an embodiment of the invention, in the step (b), the first connecting layer between any two adjacent first type epitaxial structures is removed by etching to form the first layers separated from each other. a connection.

In an embodiment of the invention, in the above step (a), the method of forming the first type epitaxial structures on the first substrate comprises: (a-1) forming the first growth carriers on the first growth carrier. The first type of epitaxial structure. (a-2) Remove the first growth carrier. (a-3) Forming the first connection layer and the first adhesive layer, and bonding the first type epitaxial structures to the first substrate through the first adhesive layer.

In an embodiment of the invention, the step (a-1) and the step (a-2) further comprise: (a-1-1) forming a dummy fixing layer to join the first type epitaxial structures To the temporary substrate, wherein the bonding force between the dummy fixing layer and the temporary substrate is smaller than the bonding force of the first adhesive layer and the first substrate.

In an embodiment of the invention, the dummy fixing layer further covers the first type epitaxial structures.

In an embodiment of the invention, in the above step (a), the method of forming the first type epitaxial structures on the first substrate comprises: (a-1) forming the first growth carriers on the first growth carrier. The first type of epitaxial structure. (a-2) forming a first connecting layer and a first adhesive layer, and bonding the first type epitaxial structures to the first substrate through the first adhesive layer. (a-3) Remove the first growth carrier.

A miniature light emitting diode device of the present invention includes a circuit substrate, a plurality of first type epitaxial structures, and a plurality of first connecting portions. The epitaxial structures are disposed on the circuit substrate separately from each other and electrically connected to the circuit substrate. The first connecting portions are respectively disposed on a side of the first type of epitaxial structures away from the circuit substrate, wherein a ratio of a thickness of each of the first connecting portions to a thickness of the corresponding first type of epitaxial structure is greater than or equal to 0.01 and less than Equal to 0.5.

In an embodiment of the invention, the micro-light emitting diode device further includes a plurality of second-type epitaxial structures and a plurality of second connecting portions. The second type epitaxial structures are disposed on the circuit substrate separately from each other and electrically connected to the circuit substrate. The second connecting portions are respectively disposed on a side of the second type epitaxial structure away from the circuit substrate, wherein a ratio of a thickness of each of the second connecting portions to a thickness of the corresponding second type epitaxial structure is greater than or equal to 0.01 and less than Equal to 0.5, and these first type epitaxial structures and these second type epitaxial structures respectively have different luminescent colors.

In an embodiment of the invention, the total thickness of each of the first type epitaxial structures and the corresponding first connecting portions is less than the total thickness of each of the second type epitaxial structures and the corresponding second connecting portion.

In an embodiment of the invention, each of the first type of epitaxial structures has a thickness equal to the thickness of each of the second type of epitaxial structures.

In an embodiment of the invention, the thickness of each of the first connecting portions is equal to the thickness of each of the second connecting portions.

In an embodiment of the invention, the total thickness of each of the first type epitaxial structures and the corresponding first connecting portions is equal to the total thickness of each of the second type epitaxial structures and the corresponding second connecting portion.

In an embodiment of the invention, the first connecting portions are made of an insulating material.

In an embodiment of the invention, the material of the first connecting portions comprises tantalum nitride or a group selected from the group consisting of oxides of lanthanum, aluminum, lanthanum, zirconium, hafnium and titanium.

In an embodiment of the invention, the orthographic projection area of each of the first connecting portions on the circuit substrate is greater than or equal to the orthographic projection area of the corresponding first type epitaxial structure on the circuit substrate.

In an embodiment of the invention, the micro-light emitting diode device further includes a first insulating layer covering the sidewall surfaces of each of the first-type epitaxial structures.

In an embodiment of the invention, the first insulating layer and the first connecting portion are made of the same material, and the density of the first insulating layer is greater than the density of the first connecting portion.

In an embodiment of the invention, the first insulating layer and the first connecting portion are made of different materials.

In an embodiment of the invention, the ratio of the thickness of the first connecting portion to the side length of the corresponding first type of epitaxial structure is 0.001 or more and 0.3 or less.

Based on the above, in the process of fabricating the miniature light emitting diode device, the relative positions of the plurality of first type epitaxial structures can be fixed through the first connecting layer, and then the first adhesive layer is formed on the first connecting layer and When the first substrate is bonded to the first adhesive layer, the relative positions of the first-type epitaxial structures to each other are not affected by the external force and are shifted. Therefore, when transferring the first type epitaxial structures onto the target substrate, each of the first type epitaxial structures can be accurately aligned onto the target substrate. In other words, the manufacturing method of the micro-light-emitting diode device of the present invention contributes to the improvement of the process efficiency and the process yield, and the fabricated micro-light-emitting diode device can have good reliability.

The above described features and advantages of the invention will be apparent from the following description.

1 to 11 are schematic cross-sectional views showing a method of fabricating a miniature light emitting diode device according to an embodiment of the present invention. First, referring to FIG. 1, a plurality of first-type epitaxial structures 120a separated from each other are formed on the first growth carrier 100a, wherein the first growth carrier 100a may be a sapphire substrate. In the present embodiment, the first type epitaxial structures 120a partially cover one surface of the first growth carrier 100a.

The steps of forming the first epitaxial structure 120a on the first growth carrier 100a are exemplified as follows: First, an epitaxial structure layer is formed on the first growth carrier 100a. Here, the forming step of the epitaxial structure layer is as follows: First, a semiconductor material layer is formed on the first growth substrate 100a, and the semiconductor material layer covers one surface of the first growth carrier 100a. The semiconductor material layer may be a multi-layered structure, which is doped with a Group IIA element or an IVA group element, respectively, to form a p-type semiconductor layer or an n-type semiconductor layer, or may be undoped, and is not limited thereto. Next, an active material layer is formed on the semiconductor material layer, and the active material layer covers one surface of the semiconductor material layer. Next, another layer of semiconductor material is formed on the active material layer, and another layer of semiconductor material covers one surface of the active material layer. The semiconductor material layer and the other semiconductor material layer are respectively located on opposite sides of the active material layer, and the other semiconductor material layer may be a multi-layer structure, respectively doped with a Group IIA element or a Group IVA element to form a p-type semiconductor layer or The n-type semiconductor layer may or may not be doped, and is not limited thereto. In this embodiment, the material of the semiconductor material layer, the active material layer and the other semiconductor material layer may be selected from a group II-VI material, such as zinc selenide (ZnSe), or a group III-V material, such as gallium nitride. (GaN), but not limited to this.

Finally, the epitaxial structure layer (ie, the semiconductor material layer, the active material layer, and another semiconductor material layer) is patterned by coating photoresist, exposure, lithography, and etching. That is, the epitaxial structure layer in a specific region is removed to expose a portion of the surface of the first growth carrier 100a, and the unremoved portion defines a plurality of first-type epitaxial structures 120a separated from each other. . At this time, as shown in FIG. 1, each of the first type epitaxial structures 120a includes a first type semiconductor layer 122a, a light emitting layer 124a, and a second type semiconductor layer 126a. The second type semiconductor layer 126a is connected to the first growth carrier 100a, and the light emitting layer 124a is disposed on the second type semiconductor layer 126a. The first type semiconductor layer 122a is disposed on the light emitting layer 124a, and the first type semiconductor layer 122a and the second type semiconductor layer 126a are respectively located on opposite sides of the light emitting layer 124a.

Further, the semiconductor material layer doped with the Group IIA element or the Group IVA element may form the second type semiconductor layer 126a, and another semiconductor material layer doped with the Group IIA element or the Group IVA element may form the first type semiconductor Layer 122a. If the semiconductor material layer is doped with a Group IVA element, such as germanium (Si), and the n-type semiconductor layer 122a is formed, the other semiconductor material layer may be doped with a Group IIA element, such as magnesium (Mg), to form a p-type semiconductor. Floor. On the other hand, if the semiconductor material layer is doped with a Group IIA element, such as magnesium (Mg), to form a p-type semiconductor layer, the other semiconductor material layer may be doped with a Group IVA element, such as germanium (Si), to form an n-type. Semiconductor layer. That is, the first type semiconductor layer 122a and the second type semiconductor layer 126a may be a combination of a p-type semiconductor layer and an n-type semiconductor layer. On the other hand, the light-emitting layer 124a may be a multiple quantum well (MQW) structure formed of an active material layer.

Next, referring to FIG. 2, a bonding pad 130a is formed on each of the first type epitaxial structures 120a, wherein the bonding pads 130a and the first growth carrier 100a are respectively located on opposite sides of the first type epitaxial structures 120a. And each of the first type epitaxial structures 120a is electrically connected to the corresponding bonding pad 130a.

In this embodiment, the first type of epitaxial structures 120a may be horizontal LEDs, wherein each bonding pad 130a is disposed on the corresponding first type semiconductor layer 122a, and each bonding pad 130a and the corresponding light emitting layer 124a are respectively located on opposite sides of the corresponding first type semiconductor layer 122a. Each of the bonding pads 130a may include a first type electrode 132a and a second type electrode 134a that are electrically different from each other, wherein the first type electrode 132a is electrically connected to the first type semiconductor layer 122a, and the second type electrode 134a and the second type The type semiconductor layer 126a is electrically connected. The first type electrode 132a and the second type electrode 134a may be a combination of a p-type electrode and an n-type electrode. When the first type semiconductor layer 122a is a p-type semiconductor layer and the second type semiconductor layer 126a is an n-type semiconductor layer, the first type electrode 132a is a p-type electrode and the second type electrode 134a is an n-type electrode. On the other hand, if the first type semiconductor layer 122a is an n-type semiconductor layer and the second type semiconductor layer 126a is a p-type semiconductor layer, the first type electrode 132a is an n-type electrode and the second type electrode 134a is a p-type electrode.

In this embodiment, the first type of epitaxial structures 120a may be micro LEDs, wherein each of the first type epitaxial structures 120a has a maximum width of between about 1 and 100 microns, preferably. It is between 3 and 50 microns. On the other hand, the thickness of each of the first type epitaxial structures 120a is between about 1 and 6 microns, and too thick or too thin will affect the subsequent process yield. In each of the first type epitaxial structures 120a, the thickness of the second type semiconductor layer 126a may be greater than the thickness of the first type semiconductor layer 122a, wherein the thickness of the second type semiconductor layer 126a is between about 1 and 5 microns, and the light is emitted. The thickness of the layer 124a is between about 0.1 and 1 micron, and the thickness of the first type semiconductor layer 122a is between about 0.1 and 0.5 micron, but not limited thereto. In particular, the first type of epitaxial structure 120a has a rectangular cross section, but in the embodiment not shown, the first type of epitaxial structure may have a trapezoidal cross section, for the first type of epitaxial The geometry of the cross-section of the structure is not limited by the present invention.

Referring to FIG. 2, each of the first type epitaxial structures 120a has a sidewall surface 125a and a bonding surface 128a connected to each other, wherein the bonding surface 128a is a surface where the bonding pad 130a is located, and the sidewall surface 125a and the bonding surface 128a are mutually Vertically, or the angle between the side wall surface 125a and the joint surface 128a is an obtuse angle, thereby reducing the complexity of subsequent processes. In order to prevent water oxygen from invading the first type of epitaxial structures 120a, a first insulating layer 140a may be formed on the bonding surface 128a of each of the first type epitaxial structures 120a and the sidewall surface 125a, but each of the first insulating layers 140a The bond pads 130a on the bonding surface 128a of the corresponding first type epitaxial structure 120a are exposed for subsequent electrical bonding. On the other hand, the first insulating layer 140a on the sidewall faces 125a of the first type epitaxial structures 120a may be on the surface of the first growth carrier 100a between any two adjacent first epitaxial structures 120a. connection. Here, the material of the first insulating layer 140a may be including tantalum nitride or a group selected from oxides of lanthanum, aluminum, lanthanum, zirconium, hafnium, and titanium, such as cerium oxide or oxidation. Aluminum (Al ₂ O ₃ ). In other embodiments, the first insulating layer may not be formed on the bonding surface and the sidewall surface of the first type epitaxial structure, so that the bonding surface and the sidewall surface of the first type epitaxial structure are directly exposed to the outside.

Next, referring to FIG. 3, the dummy fixing layer 150a may be formed on the first growth carrier 100a by spin coating or other suitable injection molding method, and further, the dummy fixing layer 150a may be coated with the first type epitaxial structures 120a, These bonding pads 130a and these first insulating layers 140a. In this embodiment, the dummy fixing layer 150a fills the gap between any two adjacent first type epitaxial structures 120a to cover the surface of the first growth carrier 100a located in the gap. After the dummy fixing layer 150a is formed on the first growth carrier 100a, the temporary substrate 160a is bonded (or bonded) to the dummy fixing layer 150a, and the temporary substrate 160a and the first growth carrier 100a are respectively located on the dummy substrate 150a. The opposite sides of the fixed layer 150a. Specifically, the temporary substrate 160a and the first growth carrier 100a may be selected from the same material. For example, the temporary substrate 160a and the first growth carrier 100a may both be sapphire substrates to avoid differences in thermal expansion coefficients. Deformation occurs when engaged.

Next, referring to FIG. 4 and FIG. 5, the first growth carrier 100a may be removed by a laser lift-off method or other suitable removal method, and the first connection layer 110a is formed on the first-type epitaxial structures 120a and On the fixed layer 150a, the first connecting layer 110a and the temporary substrate 160a are respectively located on opposite sides of the dummy fixing layer 150a, and the first connecting layer 110a is disposed to fix the relative relationship between the first type of epitaxial structures 120a. position. On the other hand, the ratio of the thickness of the first connection layer 110a to the thickness of each of the first type epitaxial structures 120a is greater than 0.01 and less than or equal to 0.5. If the ratio is greater than 0.5, the process difficulty of subsequently forming the plurality of first connecting portions separated from each other is increased. If the ratio is less than or equal to 0.01, the connecting force of the first connecting layer 110a and each of the first type epitaxial structures 120a is increased. It may not be enough. The first connection layer 110a directly connects the dummy pinned layer 150a, the first insulating layer 140a, and the second type semiconductor layer 126a. The material of the first connection layer 110a may be an insulating material and has a melting point of more than 1000 ° C, and can withstand high temperature and high pressure during the connection. For example, the material of the first connection layer 110a may include tantalum nitride (Si ₃ N _{4 ).} Or, comprising a group selected from the group consisting of oxides of lanthanum, aluminum, lanthanum, zirconium, hafnium and titanium, such as cerium oxide (SiO ₂ ) or aluminum oxide (Al ₂ O ₃ ).

Then, the first adhesive layer 170a is formed on the first connection layer 110a by spin coating or other suitable glue injection method, and the first substrate 180a is attached to (or attached to) the first adhesive layer 170a. . That is, the first substrate 180a is connected to the first connection layer 110a through the first adhesive layer 170a, and the temporary substrate 160a and the first substrate 180a are respectively located on opposite sides of the dummy fixing layer 150a. Here, the connection force of the dummy fixing layer 150a and the temporary substrate 160a is smaller than the connection force of the first adhesive layer 170a and the first substrate 180a. The melting point of the first connecting layer 110a is greater than the melting point of the dummy fixing layer 150a and the first adhesive layer 170a. Since the relative positions between the first type epitaxial structures 120a covered by the dummy fixing layer 150a and separated from each other can be fixed by the first connecting layer 110a, the first substrate 180a is connected through the first adhesive layer 170a. At the time of the first connection layer 110a, even if the dummy fixing layer 150a flows due to heat, the relative positions of the first type epitaxial structures 120a are not shifted from each other. Here, the Young's modulus of the first connection layer 110a is greater than the Young's modulus of the first adhesive layer 170a, except that the relative positions of the first type of epitaxial structures 120a are transmitted through the first connection layer 110a which is not easily deformed. The first adhesive layer 170a can also serve as a buffer when the first substrate 180a is connected to the first connection layer 110a. Here, the material of the first adhesive layer 170a is, for example, a high molecular polymer. Specifically, the first substrate 180a and the temporary substrate 160a may be selected from the same material. For example, the first substrate 180a and the temporary substrate 160a may both be sapphire substrates to avoid deformation during bonding due to different thermal expansion coefficients. .

Next, referring to FIG. 6, the substrate 160a may be temporarily removed by a laser lift-off method or other suitable removal method, and the dummy fixing layer 150a may be removed by laser ablation, ultraviolet light irradiation, solution decomposition or thermal decomposition. Further exposing the bonding pads 130a, the first type epitaxial structures 120a, the first insulating layers 140a, and the first connecting layer 110a between any two adjacent first type epitaxial structures 120a, due to the dummy fixing layer The connection force between the 150a and the temporary substrate 160a is smaller than the connection force of the first adhesive layer 170a and the first substrate 180a, so that the connection of the first adhesive layer 170a and the first substrate 180a is not affected during the removal process.

Next, referring to FIG. 6 and FIG. 7 simultaneously, the first connection layer 110a between any two adjacent first type epitaxial structures 120a may be removed by wet etching or other suitable removal to form each other. The plurality of first connecting portions 210a are separated, and the first connecting portions 210a allow light to pass therethrough. The first connection portion 210a is connected to the second type semiconductor layer 126a, wherein the first connection portion 210a and the light-emitting layer 124a are respectively located in the first arrangement portion 210a of the first-type epitaxial structure 120a and the corresponding first connection portion 210a. The opposite sides of the two-type semiconductor layer 126a, and the second-type semiconductor layer 126a and the first-type semiconductor layer 122a are respectively located on opposite sides of the light-emitting layer 124a.

Here, under the same etching condition, the etching rate of the material of the first connection layer 110a may be greater than the etching rate of the first insulating layer 140a, so as not to affect the configuration in the process of removing the first connection layer 110a by etching. The first type insulating layer 140a on the first type epitaxial structure 120a. In an embodiment of the invention, the material of the first connection layer 110a and the first insulation layer 140a may be the same material, and the material density of the first connection layer 110a is greater than the material density of the first insulation layer 140a. In another embodiment of the present invention, the material of the first connection layer 110a and the first insulation layer 140a may be different materials. For example, the material of the first connection layer 110a may be ceria and the first insulation layer. The material of 140a may be tantalum nitride, which is not limited in the present invention.

In this embodiment, the side surface 141a of each of the first insulating layers 140a is aligned with the side surface 211a of the first connecting portion 210a on the corresponding first type epitaxial structure 120a, and thus the respective first connecting portions 210a are on the first substrate 180a. The upper projected area is equal to the orthographic projection area of the corresponding first type epitaxial structure 120a on the first substrate 180a. That is, the orthographic projection of each of the first type epitaxial structures 120a on the first substrate 180a completely overlaps with the orthographic projection of the corresponding first connection portion 210a on the first substrate 180a. In other embodiments, the sides of the respective first connecting portions may slightly exceed the sides of the first insulating layer corresponding to the first type of epitaxial structure, and thus the orthographic projection areas of the respective first connecting portions on the first substrate are larger than corresponding The front projection area of the first type epitaxial structure on the first substrate, preferably, the orthographic projection area of each first connection portion on the first substrate and the corresponding first type epitaxial structure on the first substrate The ratio of the projected area is less than or equal to 1.1. If the ratio is greater than 1.1, the first type of epitaxial structures cannot be closely arranged, which affects the application efficiency of the subsequent first type of epitaxial structure on the miniature light emitting diode device. That is, the orthographic projection of each of the first type epitaxial structures on the first substrate falls within the orthographic projection of the corresponding first connection portion on the first substrate.

Referring to FIG. 8 , at least a portion of the first type epitaxial structure 120 a is electrically bonded to the target substrate 200 through a bonding process, such as a thermal bonding process. Here, only part of the first type epitaxial structure 120a is bonded to the target substrate 200 through a bonding process. In an embodiment not shown, all of the first type epitaxial structures can also be transferred to the target substrate. Referring to FIG. 9, the first substrate 180a is removed by a laser lift-off method or other suitable removal method, and then the first adhesive layer 170a is removed by wet etching or other suitable removal. In this embodiment, each of the first connecting portions 210a is disposed on the second type semiconductor layer 126a, wherein a ratio of a thickness of each of the first connecting portions 210a to a thickness of the corresponding first type epitaxial structure 120a is greater than 0.01 and less than or equal to 0.5. .

In the above fabrication steps, the relative positions of the first type epitaxial structures 120a are not offset from each other, so when the first type epitaxial structure 120a is transferred onto the target substrate 200, the first type epitaxial structure 120a The upper bonding pad 130a can be accurately aligned to the electrode bonding layer (not shown) on the target substrate 200, which helps to improve process efficiency and process yield.

With reference to FIG. 10, in the embodiment, after the first type epitaxial structure 120a is transferred onto the target substrate 200, a plurality of second type epitaxial structures 120b are formed on the second substrate 180b. The second type of epitaxial structures 120b are separated from each other, and a second connecting portion 210b is disposed between each of the second type of epitaxial structures 120b and the second substrate 180b, and the second connecting portions 210b are connected through the second adhesive layer 170b. The second substrate 180b. Wherein, the first type epitaxial structure 120a and the second type epitaxial structure 120b may have different luminescent colors. Thereafter, at least a portion of the second type epitaxial structure 120b is electrically coupled to the target substrate 200 by a bonding process, such as a thermal compression process. Specifically, the steps of forming the second epitaxial structure 120b and the second connecting portions 210b to connect the second substrate 180b through the second adhesive layer 170b can be substantially referred to the steps shown in FIG. 1 to FIG. Repeat it. After the at least a portion of the second type epitaxial structure 120b is passed through the bonding process to electrically bond the corresponding bonding pad 130b to the target substrate 200, the second substrate 180b may be removed by a laser lift-off method or other suitable removal method. Next, the second adhesive layer 170b is removed by wet etching or other suitable removal. In particular, each of the second connecting portions 210b and the corresponding second-type epitaxial structure 120b also have the same or similar structural features as the respective first connecting portions 210a and the corresponding first-type epitaxial structures 120a.

Here, the total thickness of each of the first type epitaxial structures 120a and the corresponding first connection portions 210a is smaller than the total thickness of each of the second type epitaxial structures 120b and the corresponding second connection portions 210b. The thickness of each of the first connecting portions 210a is smaller than the thickness of each of the second connecting portions 210b on the premise that the thickness of each of the first type epitaxial structures 120a and the thickness of each of the second type epitaxial structures 120b are equal to each other. Each of the first type epitaxial structures 120a is electrically bonded to the target substrate 200 and the second epitaxial structures 120b are electrically bonded to the target substrate 200, that is, according to the epitaxial structure and the corresponding connection portion. The order of the total thickness is first transferred to each of the first type of epitaxial structures 120a and the corresponding first connecting portions 210a having the thinnest total thickness to the target substrate 200, and then the second epitaxial structures of the second thin total thickness are thinned. The 120b and the corresponding second connecting portion 210b are transferred onto the target substrate 200. Since the total thickness of each of the first type epitaxial structures 120a and the corresponding first connection portions 210a transferred to the target substrate 200 is thinner, each of the second type epitaxial structures 120b and the corresponding second connection portion are subsequently transferred. When the 210b is on the target substrate 200, the second adhesive layer 170b does not contact the first type of epitaxial structures 120a that have been transferred onto the target substrate 200 and the first connection portion 210a, thereby avoiding the transfer to the target substrate 200. The first type epitaxial structure 120a and the first connecting portion 210a are pressed to cause breakage.

Please continue to refer to FIG. 11 , which schematically illustrates the final transfer of the third-type epitaxial structure 120 c having the thickest total thickness and the corresponding third connection portion 210 c onto the target substrate 200 . For example, the steps of forming the third type epitaxial structure 120c and the corresponding third connecting portion 210c and transferring the respective second type epitaxial structures 120b and the corresponding second connecting portion 210b to the target substrate 200 are as follows. The steps shown in FIG. 10 are not repeated here. In particular, each of the third connecting portions 210c and the corresponding third-type epitaxial structure 120c also have the same or similar structural features as the respective first connecting portions 210a and the corresponding first-type epitaxial structures 120a. Here, before transferring each of the third-type epitaxial structures 120c and the corresponding third connecting portions 210c to the target substrate 200, each of the first-type epitaxial structures 120a and the corresponding first connecting portions 210a and each of the second-type epitaxial grains The structure 120b and the corresponding second connecting portion 210b are successively transferred onto the target substrate 200.

Since the total thickness of each of the third type epitaxial structures 120c and the corresponding third connection portions 210c is the thickest, when each of the third type epitaxial structures 120c and the corresponding third connection portion 210c are transferred to the target substrate 200, The three adhesive layers (not shown) are not in contact with the first type of epitaxial structures 120a and the first connecting portions 210a that have been transferred onto the target substrate 200 and the second type of epitaxial structures 120b and the second connecting portions 210b. These first type epitaxial structures 120a and the first connection portions 210a which have been transferred onto the target substrate 200 and the second type epitaxial structures 120b and the second connection portions 210b are prevented from being damaged to be damaged.

In this embodiment, the connecting portions (including the first connecting portion 210a, the second connecting portion 210b, and the third connecting portion 210c) and the target substrate 200 are respectively located in the epitaxial structures (including the first type epitaxial structure 120a, the first The opposite sides of the two-type epitaxial structure 120b and the third-type epitaxial structure 120c). For example, the target substrate 200 can be a circuit substrate. The circuit substrate is embodied as a display panel, such as a complementary metal oxide semiconductor (CMOS) substrate, a germanium-based liquid crystal (LCOS) substrate, a thin film transistor (TFT) substrate, or other substrate having a working circuit. The electrode substrate (ie, the target substrate 200) is provided with an electrode bonding layer on a side of the epitaxial structure (including the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c) (not shown), and each of the epitaxial structures (including the first type of epitaxial structure 120a, the second type of epitaxial structure 120b, and the third type of epitaxial structure 120c) is passed through a corresponding bonding pad (including The bonding pads 130a to 130c are electrically connected to the electrode bonding layer (not shown) to be electrically connected to the target substrate 200. The first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c may have different luminescent colors. For example, the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c may be a red light micro-epitaxial structure (or red light micro-light emitting diode), green light A combination of a miniature epitaxial structure (or a green light-emitting diode) and a blue micro-exfoliation structure (or a blue micro-light emitting diode).

In the above fabrication steps, the relative positions of the epitaxial structures (including the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c) are not offset from each other, and thus When the epitaxial structures (including the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c) are transferred onto the target substrate 200, each epitaxial structure (including the first type of epitaxial crystal) The bonding pads (including the bonding pads 130a to 130c) on the structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c) can be accurately aligned to the electrode bonding layer (not shown) on the target substrate 200. It helps to improve process efficiency and process yield.

In this embodiment, the orthographic projection area of each of the first connecting portions 210a on the target substrate 200 is equal to the orthographic projection area of the corresponding first type epitaxial structure 120a on the target substrate 200. That is, the orthographic projection of each of the first type epitaxial structures 120a on the target substrate 200 completely overlaps with the orthographic projection of the corresponding first connection portion 210a on the target substrate 200. Specifically, each of the second connecting portions 210b and the corresponding second-type epitaxial structure 120b also have the same or similar structural features described above, and each of the third connecting portions 210c and the corresponding third-type epitaxial structure 120c also has The same or similar structural features described above. In other embodiments, the sides of the respective connecting portions may slightly exceed the sides of the insulating layer on the corresponding epitaxial structure, so that the orthographic projection area of each connecting portion on the target substrate is greater than that of the corresponding epitaxial structure on the circuit substrate. Preferably, the projection area, preferably, the ratio of the orthographic projection area of each connection portion on the target substrate to the orthographic projection area of the corresponding epitaxial structure on the target substrate is greater than 1 and less than or equal to 1.1. That is, the orthographic projection of each epitaxial structure on the target substrate falls within the orthographic projection of the corresponding connection portion on the target substrate.

It can be seen from the above manufacturing steps that the connecting portions (including the first connecting portion 210a, the second connecting portion 210b, and the third connecting portion 210c) separated from each other are partially removed from the connecting layer (including the first connecting layer 110a, the second connection) a layer (not shown) and a third connecting layer (not shown) are formed, wherein the thickness of each connecting portion (including the first connecting portion 210a, the second connecting portion 210b, and the third connecting portion 210c) and the corresponding Lei The ratio of the thickness of the crystal structure (including the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c) is greater than 0.01 and less than or equal to 0.5 represents the connection layer (including the first connection layer 110a, The thickness of the second connection layer (not shown) and the third connection layer (not shown) and the corresponding epitaxial structure (including the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type of Lei The ratio of the crystal structure 120c) is also greater than 0.01 and less than or equal to 0.5, if the thickness of the connection layer (including the first connection layer 110a, the second connection layer (not shown), and the third connection layer (not shown) and corresponding An epitaxial structure (including a first type epitaxial structure 120a, a second type epitaxial structure 120b, and The thickness ratio of the third type epitaxial structure 120c) is greater than 0.5, and the connection layer is partially removed (including the first connection layer 110a, the second connection layer (not shown), and the third connection layer (not shown). The process is hindered. If the thickness is less than or equal to 0.01, the connecting layer (including the first connecting layer 110a, the second connecting layer (not shown) and the third connecting layer (not shown)) and the corresponding epitaxial structure (including the first type of epitaxial The connection force of the structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c) may be too small. Specifically, each of the epitaxial structures (including the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c) has a thickness of, for example, 5 micrometers, and a corresponding connection portion (including the first The thickness of the connection layer 110a, the second connection layer (not shown), and the third connection layer (not shown) is, for example, 0.1 to 2 μm, which is not limited herein. Specifically, the thickness of the connecting portion (including the first connecting portion 210a, the second connecting portion 210b, and the third connecting portion 210c) and the corresponding epitaxial structure (including the first type epitaxial structure 120a, the second type of epitaxial crystal) The ratio of the maximum width of the structure 120b and the third type epitaxial structure 120c) is between 0.001 and 0.3. When the thickness is less than 0.001, the thickness of the connecting portion (including the first connecting portion 210a, the second connecting portion 210b, and the third connecting portion 210c) may be too thin, and the insufficient connecting force may cause the epitaxial structure (including the first type epitaxial structure 120a, The relative position between the second type epitaxial structure 120b and the third type epitaxial structure 120c) varies during the process. When it is greater than 0.3, the thickness of the connecting portion (including the first connecting portion 210a, the second connecting portion 210b, and the third connecting portion 210c) may be too thick, that is, the excessively thick connecting layer (including the first connecting layer 110a) is partially removed. The process of the second connection layer (not shown) and the third connection layer (not shown) may cause hindrance, and reduce the formation of the respective connection portions (including the first connection portion 210a, the second connection portion 210b, and the third Process yield at the time of connection portion 210c). Preferably, when the maximum width of the epitaxial structure (including the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c) is less than 50 micrometers, the connecting portion (including the first connecting portion) The thickness of the 210a, the second connecting portion 210b, and the third connecting portion 210c) and the corresponding epitaxial structure (including the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c) The ratio of the width is between 0.002 and 0.2; when the maximum width of the epitaxial structure (including the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c) is 50 μm or more, the connection portion (including the first connecting portion 210a, the second connecting portion 210b, and the third connecting portion 210c) and the corresponding epitaxial structure (including the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type of Lei The ratio of the maximum width of the crystal structure 120c) is between 0.001 and 0.04.

In this embodiment, the micro-light-emitting diode device 10 includes a circuit substrate (ie, a target substrate 200) and a plurality of epitaxial structures (including a first-type epitaxial structure 120a, a second-type epitaxial structure 120b, and a third-type Lei The crystal structure 120c), the plurality of bonding pads (including the bonding pads 130a to 130c), and the plurality of connecting portions (including the first connecting portion 210a, the second connecting portion 210b, and the third connecting portion 210c). The epitaxial structures (including the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c) are disposed on the circuit substrate (ie, the target substrate 200) and are separated from each other. The bonding pads (including the bonding pads 130a to 130c) are respectively disposed on the epitaxial structures (including the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c), and the epitaxial structure (including the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c) electrically connected to the circuit substrate through the corresponding bonding pads (including the bonding pads 130a to 130c) (ie, the target substrate 200) ). The connecting portions (including the first connecting portion 210a, the second connecting portion 210b, and the third connecting portion 210c) are respectively disposed on the epitaxial structures (including the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third The epitaxial structure 120c) has a light guiding function to make these epitaxial structures have better light extraction efficiency. More specifically, the refractive index of the connecting portion (including the first connecting portion 210a, the second connecting portion 210b, and the third connecting portion 210c) may be smaller than the epitaxial structures (including the first type epitaxial structure 120a, the second type of Lei The refractive index of the crystal structure 120b and the third type epitaxial structure 120c) is greater than the refractive index of the air to avoid total reflection in the epitaxial structure during light extraction and affect the light extraction efficiency. The connecting portions (including the first connecting portion 210a, the second connecting portion 210b, and the third connecting portion 210c) and the circuit substrate (ie, the target substrate 200) are respectively located in the epitaxial structures (including the first type epitaxial structure 120a, the second The opposite sides of the epitaxial structure 120b and the third epitaxial structure 120c), and the epitaxial structures (including the first epitaxial structure 120a, the second epitaxial structure 120b, and the third epitaxial structure 120c) The circuit substrate (ie, the target substrate 200) is located on opposite sides of the bonding pads (including the bonding pads 130a to 130c). The material of the connecting portion (including the first connecting portion 210a, the second connecting portion 210b, and the third connecting portion 210c) may be an insulating material, and the melting point is greater than 1000 ° C. For example, the connecting portions (including the first connecting portion 210a) The material of the second connecting portion 210b and the third connecting portion 210c) may include tantalum nitride or a group including an oxide selected from the group consisting of lanthanum, aluminum, lanthanum, zirconium, hafnium, and titanium, for example, Ceria or alumina.

Figure 12 is a top plan view of a miniature light emitting diode device in accordance with an embodiment of the present invention. Referring to FIG. 12, in the embodiment, the miniature light emitting diode device 10 is embodied as a miniature light emitting diode display panel. In practice, the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c can be respectively fabricated through the above fabrication steps, and the first type epitaxial structure 120a and the second type epitaxial structure The 120b and the third type epitaxial structure 120c may have different luminescent colors, respectively. For example, the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c may be a red light micro-epitaxial structure (or red light micro-light emitting diode), green light A combination of a miniature epitaxial structure (or a green light-emitting diode) and a blue micro-exfoliation structure (or a blue micro-light emitting diode). The micro-light-emitting device 10 can be obtained by transferring the first-type epitaxial structure 120a, the second-type epitaxial structure 120b, and the third-type epitaxial structure 120c to the circuit substrate (ie, the target substrate 200). In detail, the first type epitaxial structure 120a is self-columned on the circuit substrate (ie, the target substrate 200), and the second type epitaxial structure 120b is self-aligned on the circuit substrate (ie, the target substrate 200), and The third type epitaxial structure 120c is self-aligned on the circuit substrate (ie, the target substrate 200), and thus may be the first type epitaxial structure 120a and the second type in the row direction RD perpendicular to the column direction CD. The epitaxial structure 120b and the third epitaxial structure 120c are arranged in a reverse order. In other embodiments, the arrangement order of the red light micro-light emitting diode, the green light micro light emitting diode, and the blue light micro light emitting diode in the row direction may be modulated according to actual needs, and the invention is not limited.

The circuit substrate (ie, the target substrate 200) can be divided into a display area 201 and a non-display area 202, and the first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type of Lei are sequentially adjacent in the row direction RD. The crystal structure 120c may constitute a pixel structure P and is located in the display region 201. In other words, at least three epitaxial structures may constitute a pixel structure P. On the other hand, the data driving circuit DL and the scan driving circuit SL are located in the non-display area 202, wherein the data driving circuit DL is electrically connected to each pixel structure P for transmitting the data signal to each pixel structure. The first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c, wherein the scan driving circuit SL is electrically connected to each pixel structure P for transmitting the scan signal to each picture The first type epitaxial structure 120a, the second type epitaxial structure 120b, and the third type epitaxial structure 120c in the prime structure. Each pixel structure P is electrically connected to the control device CTR through the data driving circuit DL and the scan driving circuit SL. The control device CTR is configured to send a control signal to the driving circuit DL and the scan driving circuit SL to receive the data of the control signal. The driving circuit DL and the scan driving circuit SL respectively send data signals and scanning signals to each pixel structure P to control and drive the first type epitaxial structure 120a and the second type epitaxial structure 120b in each pixel structure P. And the light output of the third type epitaxial structure 120c.

Figure 13 is a cross-sectional view showing a light emitting diode device according to another embodiment of the present invention. Referring to FIG. 13, the light-emitting device 10A of the present embodiment is substantially similar to the light-emitting device 10 of the above embodiment, and the difference is that the thickness of each of the first connecting portions 210a, the thickness of each of the second connecting portions 210b, and each The thickness of the third connecting portion 210c is equal to each other, and the total thickness of each of the first type epitaxial structures 120a and the corresponding first connecting portion 210a is smaller than each of the second type epitaxial structures 120b and the corresponding second connecting portion 210b. The total thickness, and the total thickness of each of the second type epitaxial structures 120b and the corresponding second connection portions 210b is smaller than the total thickness of each of the third type epitaxial structures 120c and the corresponding third connection portions 210c. The thickness of each of the first type epitaxial structures 120a is smaller than the thickness of each of the second type epitaxial structures 120b, and the thickness of each of the second type epitaxial structures 120b is smaller than the thickness of each of the third type epitaxial structures 120c. On the other hand, the sequence of transferring the epitaxial structure onto the target substrate 200 can be referred to the above embodiment, and details are not described herein. The thickness of each of the first connecting portions 210a, the thickness of each of the second connecting portions 210b, and the thickness of each of the third connecting portions 210c are equal to each other, and the manufacturing process can be relatively simple.

Figure 14 is a cross-sectional view showing a micro-light emitting diode device according to still another embodiment of the present invention. Referring to FIG. 14, the light-emitting device 10B of the present embodiment is substantially similar to the light-emitting device 10 of the above embodiment, and the difference is that the total thickness of each of the first-type epitaxial structures 120a and the corresponding first connecting portion 210a is The total thickness of a second type of epitaxial structure 120b and the corresponding second connecting portion 210b and the total thickness of each of the third type of epitaxial structures 120c and the corresponding third connecting portion 210c are equal to each other, wherein each of the first type The thickness of the epitaxial structure 120a is smaller than the thickness of each of the second type epitaxial structures 120b, and the thickness of each of the second type epitaxial structures 120b is smaller than the thickness of each of the third type epitaxial structures 120c. Therefore, the thickness of each of the first connecting portions 210a is greater than the thickness of each of the second connecting portions 210b, and the thickness of each of the second connecting portions 210b is greater than the thickness of each of the third connecting portions 210c. According to the thicknesses of the first connecting portion 210a, the second connecting portion 210b, and the third connecting portion 210c, each of the first type epitaxial structures 120a provided with the thickest first connecting portion 210a is first transferred to the circuit substrate (ie, On the target substrate 200), each of the second type epitaxial structures 120b provided with the second thick connection portion 210b is transferred to the circuit substrate (ie, the target substrate 200), and finally the thinnest portion is provided. Each of the third type epitaxial structures 120c of the three connection portions 210c is transferred onto the wiring substrate (i.e., the target substrate 200). Since the epitaxial structure on the circuit substrate (ie, the target substrate 200) is first provided with a thick connection portion, the buffering effect can be exerted to avoid the epitaxy that has been transferred to the circuit substrate (ie, the target substrate 200). The structure is damaged due to pressure. Specifically, the Young's modulus of the first connecting portion 210a, the second connecting portion 210b, and the third connecting portion 210c are smaller than the corresponding first type epitaxial structure 120a, second type epitaxial structure 120b, and third type, respectively. The Young's modulus of the epitaxial structure 120c can provide a better buffering effect.

15 to FIG. 16 are schematic cross-sectional views showing a method of fabricating a miniature light emitting diode device according to still another embodiment of the present invention. Referring to FIG. 15 to FIG. 16 , the manufacturing method of the illuminating device of the present embodiment is substantially similar to the manufacturing method of the illuminating device 10 of the above embodiment, and the difference is that the illuminating device of the embodiment is on the first growth carrier 100a. After forming the first type epitaxial structure 120a separated from each other, the first connection layer 1101 is formed. Next, the dummy fixing layer 150a is formed, and these first type epitaxial structures 120a are bonded to the temporary substrate 160a by the dummy fixing layer 150a.

Then, referring to FIG. 16, the first growth carrier 100a is removed. In other words, the first connection layer 1101 of the present embodiment is formed before the first growth carrier 100a is removed. The steps of subsequently electrically bonding the first type epitaxial structure 120a to the target substrate 200 can be substantially referred to the steps shown in FIG. 5 to FIG. 9, and details are not described herein again. Through the first connection layer 1101, the relative positions of the first type epitaxial structures 120a can be fixed to each other, and the first type epitaxial structures 120a can be accurately aligned on the target substrate 200. Specifically, the first connection layer 1101 formed on each of the first type epitaxial structures 120a may expose the bonding pads 130a on the corresponding first type epitaxial structures 120a for subsequent electrical bonding to the target substrate. on.

In summary, in the process of fabricating the miniature light-emitting diode device, the relative position of the plurality of first-type epitaxial structures can be fixed through the first connecting layer, and the first adhesive layer is formed on the first connection. When the first substrate is bonded to the first adhesive layer on the layer, even if the first adhesive layer flows due to heat or stress, the relative positions of the first type of epitaxial structures are not affected by the flow. An impact occurs by the impact of an adhesive layer. Therefore, when transferring the first type epitaxial structures onto the target substrate, the bonding pads on the respective first type epitaxial structures can be accurately aligned to the electrode bonding layers on the target substrate. In other words, the manufacturing method of the micro-light-emitting diode device of the present invention contributes to the improvement of the process efficiency and the process yield, and the fabricated micro-light-emitting diode device can have good reliability.

On the other hand, in the thickness configuration, the total thickness of one of the at least two epitaxial structures capable of emitting different color lights and the corresponding connection portion is smaller than the total thickness of the other and the corresponding connection portions of the two epitaxial structures. And transferring one of the epitaxial structures having a thin total thickness and the corresponding connection portion to the circuit substrate in the transfer process, and transferring another epitaxial structure having a relatively thick total thickness and the corresponding connection portion to the circuit substrate, The epitaxial structure that has been transferred to the circuit substrate and the connection portion thereon are prevented from being damaged by the pressure.

Or alternatively, the total thickness of one of the at least two epitaxial structures capable of emitting different color lights and the corresponding connection portion is equal to the total thickness of the other and the corresponding connection portions of the two epitaxial structures, and during the transfer process First, one of the epitaxial structures provided with the thick connecting portion is transferred to the target substrate, and then another epitaxial structure provided with the thin connecting portion is transferred to the target substrate. Since the epitaxial structure on the circuit substrate is first provided with a thick connecting portion, the buffering effect can be exerted, and the epitaxial structure transferred to the target substrate can be prevented from being damaged by the pressure.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and any one of ordinary skill in the art can make some changes and refinements without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims.

10, 10A, 10B‧‧‧ miniature light-emitting diode device

100a‧‧‧First Growth Carrier

110a, 1101‧‧‧ first connection layer

120a‧‧‧first type epitaxial structure

120b‧‧‧Second type epitaxial structure

120c‧‧‧Type III epitaxial structure

122a‧‧‧first type semiconductor layer

124a‧‧‧Lighting layer

125a‧‧‧ sidewall surface

126a‧‧‧Second type semiconductor layer

128a‧‧‧ joint surface

130a~130c‧‧‧ joint pad

132a‧‧‧first type electrode

134a‧‧‧Second type electrode

140a‧‧‧Insulation

141a, 211a‧‧‧ side

150a‧‧‧Fake fixed layer

160a‧‧‧temporary substrate

170a‧‧‧First adhesive layer

170b‧‧‧Second Adhesive Layer

180a‧‧‧first substrate

180b‧‧‧second substrate

200‧‧‧ target substrate

201‧‧‧ display area

202‧‧‧Non-display area

210a‧‧‧First connection

210b‧‧‧Second connection

210c‧‧‧ third connection

CD‧‧‧ directions

CTR‧‧‧ control device

DL‧‧‧ data drive circuit

P‧‧‧ pixel structure

RD‧‧ Directions

SL‧‧‧ scan drive circuit

1 to 11 are schematic cross-sectional views showing a method of fabricating a miniature light emitting diode device according to an embodiment of the present invention. Figure 12 is a top plan view of a miniature light emitting diode device in accordance with an embodiment of the present invention. Figure 13 is a cross-sectional view showing a micro-light emitting diode device according to another embodiment of the present invention. Figure 14 is a cross-sectional view showing a micro-light emitting diode device according to still another embodiment of the present invention. 15 to FIG. 16 are schematic cross-sectional views showing a method of fabricating a miniature light emitting diode device according to still another embodiment of the present invention.

Claims (25)

A method for fabricating a miniature light-emitting diode device includes: (a) forming a plurality of first-type epitaxial structures on a first substrate, and the first-type epitaxial structures are separated from each other, wherein the first types Between the epitaxial structure and the first substrate, a first connecting layer and a first adhesive layer are connected, the first connecting layer is connected to the first type of epitaxial structures, and the first adhesive layer is located at the first connecting layer And the first substrate, wherein the Young's modulus of the first connecting layer is greater than the Young's modulus of the first adhesive layer; and (b) removing the first type of epitaxial grains located in any two adjacent layers The first connecting layer between the structures to form a plurality of first connecting portions separated from each other, wherein each of the first connecting portions is respectively connected to the corresponding first type epitaxial structure. The method for fabricating the micro-light-emitting diode device according to claim 1, further comprising: (c) electrically connecting a portion of the first-type epitaxial structures to a target substrate. The method for fabricating the miniature light-emitting diode device of claim 1, further comprising: (d) forming a plurality of second-type epitaxial structures on a second substrate, and the second type of epitaxial Separating the structures from each other, wherein the second type of epitaxial structure and the second substrate have a second connecting layer and a second adhesive layer, the second connecting layer connecting the second type of epitaxial structures, and the a second adhesive layer is located between the second connection layer and the second substrate, wherein a Young's modulus of the second connection layer is greater than a Young's modulus of the second adhesive layer; and (e) removal is located at any two Adjacent to the second connecting layer between the second type of epitaxial structures to form a plurality of second connecting portions separated from each other, wherein each of the second connecting portions and the corresponding second type of epitaxial structure respectively Connected. The method for fabricating the micro-light-emitting diode device according to claim 3, further comprising: (f) electrically bonding the portion of the first-type epitaxial structure of the step (b) to a target substrate; And (g) electrically bonding the second type epitaxial structures of the step (e) to the target substrate. The method of fabricating the miniature light emitting diode device of claim 4, wherein each of the first type of epitaxial structure and the corresponding total thickness of the first connecting portion is less than or equal to each of the second type of beam The crystal structure and the corresponding total thickness of the second connecting portion. The method of fabricating a miniature light-emitting diode device according to claim 1, wherein a ratio of a thickness of each of the first connecting portions to a thickness of the corresponding first type of epitaxial structure is greater than 0.01 and less than or equal to 0.5. The method for fabricating a miniature light-emitting diode device according to claim 1, wherein a ratio of a thickness of each of the first connection layers to a side length of the corresponding first type of epitaxial structure is greater than 0.001 and less than or equal to 0.3. . The method for fabricating the micro-light-emitting diode device according to claim 1, in the step (b), removing between the two adjacent first-type epitaxial structures by an etching method The first connecting layer is formed to form the first connecting portions separated from each other. The method for fabricating the micro-light-emitting diode device according to claim 1, wherein in the step (a), the method for forming the first-type epitaxial structures on the first substrate comprises: (a- 1) forming the first type epitaxial structures separated from each other on a first growth carrier; (a-2) removing the first growth carrier; and (a-3) forming the first connection layer and The first adhesive layer is configured to bond the first type epitaxial structures to the first substrate through the first adhesive layer. In the method for fabricating the miniature light-emitting diode device according to claim 9, the step (a-1) and the step (a-2) further comprise: (a-1-1) forming a false The fixing layer is configured to bond the first type epitaxial structures to a temporary substrate, wherein a bonding force of the dummy fixing layer and the temporary substrate is less than a bonding force of the first adhesive layer and the first substrate. The method for fabricating a miniature light-emitting diode device according to claim 10, wherein the dummy fixing layer further covers the first type of epitaxial structures. The method for fabricating the micro-light-emitting diode device according to claim 1, wherein in the step (a), the method for forming the first-type epitaxial structures on the first substrate comprises: (a- 1) forming the first type epitaxial structures separated from each other on a first growth carrier; (a-2) forming the first connection layer and the first adhesive layer, and transmitting the first adhesive layer through the first adhesive layer a first type epitaxial structure is bonded to the first substrate; and (a-3) removing the first growth carrier. A miniature light-emitting diode device includes: a circuit substrate; a plurality of first-type epitaxial structures disposed on the circuit substrate separately from each other and electrically connected to the circuit substrate; and a plurality of first connecting portions, respectively Correspondingly disposed on a side of the first type of epitaxial structure away from the circuit substrate, wherein a ratio of a thickness of each of the first connecting portions to a thickness of the corresponding first type of epitaxial structure is greater than or equal to 0.01 and less than or equal to 0.5 . The micro-light-emitting diode device of claim 13, further comprising: a plurality of second-type epitaxial structures disposed on the circuit substrate separately from each other and electrically connected to the circuit substrate; The second connecting portions are respectively disposed on the side of the second type of epitaxial structures away from the circuit substrate, wherein a ratio of a thickness of each of the second connecting portions to a thickness of the corresponding second type of epitaxial structure is greater than It is equal to 0.01 and less than or equal to 0.5, and the first type epitaxial structures and the second type epitaxial structures respectively have different luminescent colors. The micro-light-emitting diode device of claim 14, wherein a total thickness of each of the first-type epitaxial structures and the corresponding first connecting portion is smaller than each of the second-type epitaxial structures and corresponding The total thickness of the second joint. The micro-light-emitting diode device of claim 15, wherein the thickness of each of the first-type epitaxial structures is equal to the thickness of each of the second-type epitaxial structures. The micro-light emitting diode device of claim 15, wherein each of the first connecting portions has a thickness equal to a thickness of each of the second connecting portions. The micro-light-emitting diode device of claim 14, wherein a total thickness of each of the first-type epitaxial structures and the corresponding first connecting portion is equal to each of the second-type epitaxial structures and corresponding The total thickness of the second joint. The micro-light-emitting diode device according to claim 13, wherein the first connecting portions are made of an insulating material. The micro-light-emitting diode device according to claim 19, wherein the material of the first connecting portion comprises tantalum nitride or comprises oxidation selected from the group consisting of niobium, aluminum, hafnium, zirconium, hafnium and titanium. a group of objects. The micro-light-emitting diode device of claim 13, wherein an orthographic projection area of each of the first connecting portions on the circuit substrate is greater than or equal to a corresponding first-type epitaxial structure on the circuit substrate. Orthographic area. The micro-light-emitting diode device of claim 13, further comprising: a first insulating layer covering a sidewall surface of each of the first-type epitaxial structures. The micro-light-emitting diode device according to claim 22, wherein the first insulating layer and the first connecting portion are made of the same material, and the density of the first insulating layer is greater than the density of the first connecting portion. The micro-light-emitting diode device of claim 22, wherein the first insulating layer and the first connecting portion are made of different materials. The micro-light-emitting diode device according to claim 13, wherein a ratio of a thickness of each of the first connecting portions to a side length of the corresponding first-type epitaxial structure is 0.001 or more and 0.3 or less.