KR102335625B1 - Micro lighting emitting apparatus and method for manufacturing the same - Google Patents

Abstract

The present invention relates to a micro light emitting device and a method for manufacturing a micro light emitting device, and more specifically, to a high quality micro light emitting device with improved bonding characteristics and a method for manufacturing a micro light emitting device. A micro light emitting device according to an embodiment of the present invention comprises: a circuit unit (100) having a switching element selectively transmitting an electric signal, and a first electrode unit electrically connected to the switching element; a light emitting unit having a semiconductor laminate structure including an n-type semiconductor layer, an active layer, and a p-type semiconductor layer, and a second electrode unit electrically connected to the semiconductor laminate structure; a conductive bonding layer provided between the first electrode unit and the second electrode unit; and a plurality of nanorods provided on any one electrode unit of the first electrode unit or the second electrode unit and inserted at least partially into the conductive bonding layer.

Description

Micro lighting emitting apparatus and method for manufacturing the same

The present invention relates to a micro light emitting device and a method for manufacturing a micro light emitting device, and more particularly, to a high quality micro light emitting device with improved bonding characteristics and a method for manufacturing a micro light emitting device.

The micro light emitting device includes a plurality of two-dimensionally arranged light emitting pixels, and the arranged light emitting pixels can be individually flickered selectively through electrical control. The micro light emitting device is provided with a switching device for switching the voltage supplied to each light emitting pixel formed in a matrix pattern on a substrate in such a way that each light emitting pixel is individually driven by a switching device, and applies an electrical signal to the switching device It includes a circuit unit including a driving circuit for supplying it. Here, the switching device may be formed of, for example, a complementary metal-oxide semiconductor (CMOS) or a thin film transistor (TFT).

Flip-chip bonding used as a method of manufacturing such a micro light emitting device is easy to apply to a micro light emitting device because it can arrange switching elements over the entire area of the board by turning the board over and connecting to the circuit part. It has excellent mechanical properties.

However, a problem in flip chip bonding is a decrease in yield due to warpage of the substrate. In the case of organic substrates that exhibit advantages such as light weight and low dielectric constant, the coefficient of thermal expansion is relatively high, and even in the initial state at room temperature, a gap of several to tens of μm occurs in the vertical direction in a concave or convex shape, and there is an electrical gap between the electrodes. is not connected, and the reliability and quality of the micro light emitting device may be deteriorated due to poor connection.

Accordingly, electrical connection is maintained even when the substrate is tilted by pressure or heating during flip-chip bonding for manufacturing a micro light emitting device, or when a gap occurs between the electrodes of each substrate due to the inherent bending characteristics of the micro light emitting device. There is a need for a micro light emitting device and a method for manufacturing the micro light emitting device.

Korean Patent Publication No. 10-2016-0080264

The present invention relates to a high-quality micro light emitting device with improved bonding characteristics and a method for manufacturing the micro light emitting device.

A micro light emitting device according to an embodiment of the present invention includes: a circuit unit including a switching element for selectively transmitting an electric signal, and a first electrode unit electrically connected to the switching element; a light emitting unit having a semiconductor laminate structure including an n-type semiconductor layer, an active layer, and a p-type semiconductor layer, and a second electrode unit electrically connected to the semiconductor laminate; a conductive bonding layer provided between the first electrode part and the second electrode part; and a plurality of nanorods provided on one of the first electrode part and the second electrode part and inserted at least partially into the conductive bonding layer.

The strength of each of the plurality of nanorods may be equal to or greater than the strength of the conductive bonding layer.

Each of the plurality of nanorods may have a rod shape having a length greater than a diameter.

The effective planar density of the plurality of nanorods per unit area may be greater than 0% and less than or equal to 80%.

The plurality of nanorods may be made of a metal material or a conductive oxide.

Each of the plurality of nanorods may include a nanorod body providing a body of the nanorod and a metal coating layer coating a surface of the nanorod body.

It may further include a seed layer formed on any one electrode part of the first electrode part or the second electrode part provided with the plurality of nanorods to provide a nucleation location of the plurality of nanorods. .

A cover layer provided on any one of the first electrode part and the second electrode part on which the plurality of nanorods are provided, and defining a formation surface of the plurality of nanorods may be further included.

The conductive bonding layer may be made of a solder material or a liquid metal.

The light emitting unit may further include a substrate providing a laminated surface to the semiconductor laminated structure.

A plurality of the switching elements are provided to be two-dimensionally arranged, and a plurality of the semiconductor laminate structures are provided to correspond to the plurality of switching elements and are two-dimensionally arranged to form a micro LED array, each of the plurality of the semiconductor laminate structures, It may be a unit light emitting cell of a micro LED array that can be individually flickered by a corresponding switching element.

A method of manufacturing a micro light emitting device according to another embodiment of the present invention comprises the steps of: preparing a circuit unit including a switching element selectively transmitting an electric signal, and a first electrode unit electrically connected to the switching element; preparing a light emitting part having a semiconductor stacked structure including an n-type semiconductor layer, an active layer, and a P-type semiconductor layer, and a second electrode part electrically connected to the semiconductor stacked structure; forming a conductive bonding layer on any one of the first electrode part and the second electrode part; forming a plurality of nanorods on the other electrode part that is not selected among the first electrode part and the second electrode part; aligning the circuit part and the light emitting part so that the first electrode part and the second electrode part face each other; and narrowing the gap between the circuit part and the light emitting part, and bonding the first electrode part and the second electrode part while at least partially inserting the plurality of nanorods into the conductive bonding layer.

The process of forming the plurality of nanorods is a process of forming a seed layer providing nucleation positions of the plurality of nanorods on the remaining one electrode part that is not selected among the first electrode part or the second electrode part. ; and growing a plurality of nanorods on the seed layer.

In the process of forming the plurality of nanorods, a cover layer is partially provided on the remaining one electrode portion that is not selected among the first electrode portion or the second electrode portion, and defines a surface on which the plurality of nanorods are formed. process of forming; and growing a plurality of nanorods on the formation surface.

During the process of forming the plurality of nanorods, each of the plurality of nanorods may be formed in a rod shape extending forward on the other electrode part and having a length longer than a diameter.

During the process of forming the plurality of nanorods, the effective planar density of the plurality of nanorods per unit area may be greater than 0% and less than or equal to 80%.

The process of forming the plurality of nanorods may include a process of coating a metal coating layer for applying a surface of each of the plurality of nanorods to each of the plurality of nanorods.

A plurality of the switching elements are provided to be two-dimensionally arranged, and a plurality of the semiconductor laminate structures are provided to correspond to the plurality of switching elements and are two-dimensionally arranged to form a micro LED array, It may be a light emitting cell of a micro LED array that can be individually flickered by a corresponding switching element.

The micro light emitting device and the method of manufacturing the micro light emitting device according to an embodiment of the present invention provide a plurality of nanorods between the electrode part and the conductive bonding layer, thereby further improving the bonding characteristics of flip chip bonding, and thus reliability is improved. A micro light emitting device may be provided.

In particular, the micro light emitting device and the method for manufacturing the micro light emitting device according to the embodiment of the present invention include a flip chip in a micro array LED capable of individually flickering a plurality of light emitting cells by bonding a plurality of light emitting cells and a plurality of switching elements, respectively. Even if the substrate is tilted by heating or pressurization of bonding or a gap occurs between the circuit part and the light emitting part due to the inherent bending characteristics of the micro light emitting device, it is possible to prevent the non-bonding part from occurring, and to improve the reliability of the micro light emitting device. can be improved

At this time, the effective planar density of the plurality of nanorods per unit area is greater than 0% and 80% or less, so that each of the nanorods can function independently and easily inserted into the conductive junction, resulting in more reliability It is possible to provide an electrical connection in which there exists, and thus, the reliability of the micro light emitting device can be improved.

In addition, by providing a seed layer providing a nucleation location of the plurality of nanorods, bonding properties between the nanorods and the electrode can be improved, and a cover section defining a nanorod formation surface on which the nanorods are formed is provided. Accordingly, it is possible to form a plurality of nanorods only in the seed layer, and it is possible to prevent the light emitting device from malfunctioning due to the nanorods being formed at unnecessary positions.

On the other hand, in the micro light emitting device according to another embodiment of the present invention, a plurality of switching elements are connected to a plurality of semiconductor stacked structures, and the plurality of semiconductor stacked structures are provided so that they can blink individually, so as to function as a micro LED unit light emitting cell. and may be provided as a display device.

And, in the method for manufacturing a micro light emitting device according to another embodiment of the present invention, the nanorods can be inserted into the conductive junction part by bonding the circuit part and the light emitting part to face each other and narrowing the gap, and thus, the circuit part and light emission through the nanorod part It is possible to compensate for the gap between the parts, and it is possible to manufacture a micro light emitting device with improved reliability.

1 is a cross-sectional view showing a micro light emitting device according to an embodiment of the present invention.
2 is a cross-sectional view showing a micro light emitting device according to an embodiment of the present invention.
3 is a photograph showing changes in the planar microstructure and diameter of a plurality of nanorods according to process conditions according to an embodiment of the present invention.
4 is a cross-sectional view showing a light emitting unit according to an embodiment of the present invention.
5 is a view showing a process of forming a plurality of nanorods using a seed layer and a cover layer according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, only these embodiments allow the disclosure of the present invention to be complete, and the scope of the invention to those of ordinary skill in the art completely It is provided to inform you. In the description, the same reference numerals are assigned to the same components, and the sizes of the drawings may be partially exaggerated in order to accurately describe the embodiments of the present invention, and the same reference numerals refer to the same elements in the drawings.

1 is a cross-sectional view showing a micro light-emitting device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing a micro light-emitting device according to an embodiment of the present invention.

1 and 2, the micro light emitting device according to an embodiment of the present invention includes a switching device 110 that selectively transmits an electrical signal, and a first electrode part electrically connected to the switching device 110 ( A circuit unit 100 having a 120); A semiconductor stacked structure 210 including an n-type semiconductor layer 211 , an active layer 212 , and a p-type semiconductor layer 213 , and a second electrode part 220 electrically connected to the semiconductor stacked structure 210 . A light emitting unit 200 having a; and a conductive bonding layer 300 provided between the first electrode part 120 and the second electrode part 220 .

The switching element 110 is an element provided to block or transmit the electric signal by receiving an electric signal by an electric circuit, and the switching element 110 is in ohmic contact with the light emitting unit 200 and externally The blinking of the light emitting unit 200 may be controlled on/off according to an electric signal provided from the . For example, a semiconductor device such as a complementary metal-oxide semiconductor (CMOS) or a thin film transistor (TFT) may be used, but is not particularly limited. Here, the switching device 110 may include a source, a drain, and a gate structure. When a voltage is applied between the drain and the source, a current flows through the gate structure, and when a voltage is applied in the reverse direction, the current is limited.

The first electrode part 120 may be electrically connected to the switching element 110 , and may be formed of a conductive material to function as a terminal so that the switching element 110 may be electrically connected to other components. In this case, since the switching device 110 includes a source, a drain, and a gate structure, the first electrode part 120 may also include three electrode parts of a source, a drain, and a gate structure. Thus, for example, Ag, Al, Au, Cr, Cu, Ir, Mg, Nd, Ni, Pd, Pt, Rh, Ti, W may be made of any one metal or two or more alloys selected from, but in particular do not limit

The semiconductor laminate structure 210 is provided to function as a light emitting diode, and may emit light by receiving an electrical signal from the switching device 110 . The light emitting diode is a semiconductor device capable of generating light of various colors by recombination of electrons and holes in the active layer 212, which is a junction part of the n-type semiconductor layer 211 and the p-type semiconductor layer 213, when a current is applied. . In addition, since it has several advantages such as a long lifespan, low power supply, excellent initial driving characteristics, and high vibration resistance, its demand is continuously increasing.

And, unlike conventional lighting such as incandescent light bulbs or fluorescent lamps, light emitting diodes have many advantages such as ultra-small size, low power consumption, high efficiency, and eco-friendliness. .

The n-type semiconductor layer 211 may be formed on the stacked surface, and may be made of, for example, a gallium nitride-based semiconductor material. More specifically, it may be formed of a GaN layer or a GaN/AlGaN layer doped with n-type impurities, and the n-type impurities may include, for example, Si, Ge, Sn, etc., but is not limited thereto.

The active layer 212 may be formed on an n-type semiconductor and may include an InGaN/GaN layer having a multi-quantum well structure. In addition, the active layer 212 may emit light when a voltage or current is applied to the n-type semiconductor layer 211 and the p-type semiconductor layer 213 .

The p-type semiconductor layer 213 may be formed on the active layer 212 and may be made of a gallium nitride-based semiconductor material. More specifically, the p-type semiconductor layer 213 may be formed of a GaN layer or a GaN/AlGaN layer doped with p-type conductivity-type impurities, and Mg, Zn, Be, etc. may be used as the p-type conductivity type impurities. do not limit A portion of the p-type semiconductor layer 213 and the active layer 212 may be removed by etching, thereby exposing a portion of the n-type semiconductor layer 211 on the bottom surface.

In this case, the semiconductor structure may be formed by a known deposition method such as chemical vapor deposition and electron beam deposition, or a process such as sputtering. Here, the lift-off method is to remove the photoresist (PR) by applying photoresist (PR), irradiating spot-shaped ultraviolet rays to the deposition area, and developing the photoresist (PR) by depositing a deposition film (or light-shielding film) such as chromium. together with the removal of the deposited film (eg, chromium) in the non-deposited region.

The second electrode part 220 may be electrically connected to the semiconductor stacked structure 210 and formed of a conductive material to function as a terminal so that the semiconductor stacked structure 210 may be electrically connected to other components. have. At this time, since the semiconductor stacked structure 210 includes an n-type semiconductor layer 211 and a p-type semiconductor layer 213 , the second electrode part 220 also includes an n-type electrode part and a p-type electrode part. It may include an electrode part. Thus, for example, Ag, Al, Au, Cr, Cu, Ir, Mg, Nd, Ni, Pd, Pt, Rh, Ti, W may be made of any one metal or two or more alloys selected from, but in particular do not limit

The conductive bonding layer 300 is provided to electrically connect the first electrode part and the second electrode part, and is generally generated by soldering. At this time, in consideration of the need to electrically connect the electrodes and connect the semiconductors of the micro light emitting device, a material with high electrical conductivity, for example, Sn, Ag, Cu, In, or Pb, is included. and the like can be used, and there is no particular limitation here.

An underfill layer 700 filled with a thermally conductive material may be provided between the light emitting unit 200 and the circuit unit 100 . Here, the underfill technology is a method of filling the underfill of the light emitting diode package such as CSP, BGA, Filp chip, and unit light emitting unit using a thermally conductive material or insulating resin with excellent thermal conductivity. It can be used in devices that are subjected to a lot of shock.

At this time, the material constituting the underfill layer 700 may include different properties such as coefficient of thermal expansion, resistance, thermal conductivity, water resistance, and viscosity depending on the type or content of the epoxy resin, curing agent, filler, and additive, for example, It may be formed by including at least one of a curing agent such as an epoxy resin or a thermally conductive material having excellent thermal conductivity, such as _{Al 2} O _{3 , BN, and AlN.}

When the underfill layer 700 is filled and used between the circuit part 100 and the light emitting part 200 , the underfill layer 700 protects the micro light emitting device formed on the substrate from the outside, and the underfill layer 700 ) through substantially improved thermal conductivity, thereby reducing thermal expansion deformation of the circuit unit 100 and the light emitting unit 200 according to a temperature change due to heat emitted from the micro light emitting device. In addition, since a sufficiently low temperature can be maintained in at least one of the circuit unit 100 and the light emitting unit 200 , the performance and reliability of the micro light emitting device can be improved, and the lifespan of the micro light emitting device can be extended.

Meanwhile, in the micro light emitting device according to an embodiment of the present invention, the underfill layer 700 may not be provided as needed, so the underfill layer 700 may not be an essential component, and the present invention is not particularly limited thereto.

In addition, a plurality of nanorods 400 are provided on any one of the first electrode part 120 and the second electrode part 220 and are at least partially inserted into the conductive bonding layer 300 . ; may be included. The nanorod 400 is a rod-shaped structure having a diameter and length of nanometers (nm), and has various physical and chemical advantages that have not been seen in conventional bulk materials.

In the micro light emitting device according to an embodiment of the present invention, the nanorods 400 are provided on any one of the first electrode part 120 and the second electrode part 220 and inserted into the bonding layer 300 . By providing an additional connection point to the connection using the bonding layer 300 , bonding characteristics can be improved, and reliability of the micro light-emitting device can be improved.

Here, the plurality of nanorods 400 are provided on the first electrode part 120 and included in the circuit part 100 as shown in FIG. It may be formed on the second electrode part 220 and provided to the light emitting part 200 , but it is sufficient as long as it can be electrically connected, and the present invention is not particularly limited thereto.

In addition, the micro light emitting device according to an embodiment of the present invention may be a micro array light emitting device in which a plurality of switching elements 110 and a plurality of semiconductor laminate structures 210 are two-dimensionally arranged to form respective arrays and are individually connected to each other. have. In such a microarray light emitting device, one semiconductor stacked structure 210 can function as one light emitting cell, and a desired light emitting pattern can be formed by individually flickering by the plurality of switching elements 110 .

At this time, in order to electrically connect each of the plurality of switching elements 110 and the plurality of semiconductor laminate structures 210 , the light emitting unit 200 is turned over to connect to the circuit unit 100 . A flip chip is used. They can be connected by bonding. Accordingly, since the semiconductor stacked structure 210 can be arranged over the entire area, it is easy to apply to a microarray light emitting device requiring a plurality of semiconductor stacked structures 210 , that is, a plurality of light emitting cells, and the electrical connection length is short. An advantage of excellent electrical and mechanical properties may be exhibited.

Here, in each of the plurality of microarrayed light emitting cells, that is, each of the plurality of semiconductor stacked structures 210 , for example, an n-type semiconductor layer 211 is present, respectively, and each unit semiconductor stacked structure 210 is electrically separated from each other. Thus, excellent electrical properties and uniform light emission can be obtained through efficient current injection. Alternatively, the plurality of semiconductor stacked structures 210 arranged in a row at one stage may share one n-type semiconductor layer 211 and minimize the spacing between the semiconductor stacked structures 210 , but is not particularly limited thereto.

The circuit unit 100 and the light emitting unit 200 may be connected by flip-chip bonding. However, the substrate included in the light emitting unit 200 is deformed by pressing and heating by a flip-chip bonding process in which the circuit unit 100 and the light emitting unit 200 are aligned, pressed, heated, and joined to each electrode unit. This can happen.

For example, as shown in (a) of FIG. 2, the alignment is disturbed and the substrate may be inclined, or as shown in FIG. A gap may occur between the circuit units 100 , and a point at which no connection is made may occur. In addition, if the distance is further narrowed so as not to generate the gap and pressurized, a large pressure is applied to the electrode part that has already been connected, and damage or destruction may occur. Accordingly, the connection between the respective electrodes may be incomplete, and there may be a problem in that the reliability of the micro light emitting device may be deteriorated.

Accordingly, by providing a plurality of nanorods 400 on any one electrode part of the first electrode part 120 or the second electrode part 220 to compensate for the gap, the circuit part 100 Even if a gap occurs between the light emitting unit 200 and the plurality of nanorods 400, the electrical connection can be maintained, and the electrical connection between the circuit unit 100 and the light emitting unit 200 can be more reliably can be provided, and the quality of the micro light emitting device can be further improved.

The strength of each of the plurality of nanorods 400 may be equal to or greater than the strength of the conductive bonding layer 300 . Since the plurality of nanorods 400 must be provided to be connected while compensating for the gap, they must be physically connected to the bonding layer 300 . Accordingly, the strength of each of the plurality of nanorods 400 is greater than the strength of the conductive bonding layer 300 so that the plurality of nanorods 400 can be at least partially inserted into the bonding layer 300 . may be the same, and thus, may be inserted into the conductive bonding layer 300 and may be electrically connected.

In order for the nanorods 400 to be inserted into the conductive bonding layer 300 as described above, the lower the surface area of the inserted surface, the lower the surface resistance, and easy insertion may be possible even with the same force.

In this case, each of the plurality of nanorods 400 may have a rod shape having a length longer than a diameter. The smaller the diameter of the nanorods 400 is, the higher the stress applied per unit area, and the easier it is to be inserted into the conductive bonding layer 300 . However, when the diameter of the nanorods 400 is too small, it may be difficult for the nanorods 400 to withstand the applied load, which may make it difficult to be inserted into the conductive bonding layer 300 . In addition, since the nanorod 400 must be able to transfer electrons for electrical connection, if the diameter is too thin, it may be difficult to perform such an electron transfer function.

Therefore, preferably, the nanorods 400 may have a diameter of 50 nm to 1 μm, may be easily inserted into the conductive bonding layer 300 , and may not be damaged when inserted. More preferably, it has a diameter of 100 nm to 300 nm, may be more easily inserted into the conductive bonding layer 300 , and may be more structurally stable, so that the quality of the micro light emitting device can be further improved.

3 is a photograph showing changes in the planar microstructure and diameter of a plurality of nanorods 400 according to process conditions according to an embodiment of the present invention.

Referring to FIG. 3 , the effective planar density of the plurality of nanorods 400 per unit area may be greater than 0% and less than or equal to 80%. Here, the change in the planar microstructure and diameter of the plurality of nanorods 400 of FIG. 3 is performed under the process conditions of constantly controlling the process time and increasing the concentration (mol%) composition of the raw material for forming the nanorods. proceeded By simply changing the process conditions as described above, the microstructure and diameter of the nanorods 400 can be changed, so that it is possible to easily control the effective planar density of the nanorods 400 per unit area area. At this time, when the effective area of the nanorods 400 showing the preferred diameter increases too much in the total area, that is, when the density in the cross-section of the plurality of nanorods 400 is higher than 80%, the nanorods 400 is in a state like one bulk, and it may be difficult to act independently of each. On the other hand, when too little of the nanorods 400 are provided, electrical conductivity may be insufficient than a required amount.

Accordingly, the effective areal density of the nanorods 400 may be preferably 80% or less, and more preferably 10% to 50%. Accordingly, each of the plurality of nanorods 400 can function independently, can be easily inserted into the conductive bonding layer 300, and can sufficiently provide electrical conductivity necessary for electrical connection between electrodes. The reliability of the connection can be improved.

Here, the planar area refers to an area in a plan view of the plurality of nanorods 400 viewed from the upper surface, and the unit planar area refers to the planar area as a unit, in this case, the plurality of nanorods 400 in the unit planar area. The total area occupied by ) is the effective unit plan area.

Each of the plurality of nanorods 400 may have a length of 0.5 μm to 20 μm. Considering that each of the plurality of nanorods 400 may have a rod shape longer than the diameter to be inserted into the conductive bonding layer, when the diameter is several nanometers (nm) to several tens of nanometers (nm), The length may preferably be several hundred nanometers (nm) to several micrometers (μm).

However, when the nanorods 400 are provided with a length of 0.5 μm, they exhibit an excessively short length, it may be difficult to compensate for the gap, and when the nanorods 400 are provided with a length of more than 20 μm, the conductive bonding layer 300 is formed. It penetrates all and reaches the electrode portion opposite to the surface on which the plurality of nanorods 400 grow, and may damage the opposite electrode portion, or exhibit a small diameter compared to the length when inserted into the conductive bonding layer 300 and break Therefore, it may be difficult to perform the role of the bonding body of the conductive bonding layer 300 . Accordingly, more preferably, it may be provided in a range of 1 μm to 5 μm, and it can be connected without damaging the electrode part, and it can be provided with a length sufficient to keep the electrical connection more stable and to compensate for the gap.

In addition, the plurality of nanorods 400 may be made of a metal material or a conductive oxide. The plurality of nanorods 400 may have to exhibit conductivity so that an electrical connection between the electrodes is maintained. In addition, it should exhibit a higher strength than the conductive bonding layer 300 to be inserted into the conductive bonding layer (300). Accordingly, for the material of the nanorods 400 , for example, a metal material such as Ni and Cu and an alloy including the same may be used.

On the other hand, the micro light emitting device according to the embodiment of the present invention, a material used as a material of the nanorod 400, for example, may be a conductive oxide containing Al, Mg, Zn, etc., and grow The nanorod 400 can be manufactured by providing the nanorod nucleus 400' on the surface and growing the nanorod nucleus 400' in one direction by hydrothermal synthesis.

For example, to form the nanorods 400 made of ZnO, which is a conductive oxide, by hydrothermal synthesis, Zinc nitrate hexahydrate [Zn(NO ₃ ) ₂ .6H ₂ O] and Hexamethylenetetramine [(CH ₂ ) ₆ N ₄ ] is placed in the vessel, and the nanorods 400 made of ZnO can be grown while controlling the temperature, pressure, and stirring speed for a set time.

Here, in a more specific method of manufacturing a micro light emitting device according to an embodiment of the present invention, the hydrothermal synthesis method for forming a conductive oxide nanorod made of ZnO is performed in a vessel containing an aqueous solution of a material to be synthesized (CH ₂ ) ₆ N ₄ ·6H ₂ O is dissolved in DI water, the (CH ₂ ) ₆ N ₄ ·6H ₂ O is decomposed into formaldehyde (HCHO) and ammonia (NH ₃ ), and the ammonia (NH ₃ ) is an ammonium ion (NH4 ⁺ ) and the process of decomposition into hydroxide ions (OH ^{- );} By the addition of _{Zn (NO 3) 2 · 6H} 2 O to the Vessel The _{Zn (NO 3) 2 · Zn} 2 + is decomposed from the 6H ₂ O, the ammonium ion (NH4 ⁺⁾ and hydroxide ions (OH ^{-) OH -} and Zn ^{2 +} generated in the process of decomposition into A process in which Zn(OH) _{2 is synthesized by ionic bonding;} and a process in which ZnO(S) is precipitated from the synthesized Zn(OH) ₂ , and a conductive oxide nanorod made of ZnO is formed.

On the other hand, in order to manufacture the metal nanorods 400, for example, a photo resist (PR) is deposited on the ZnO nanorods formed by the hydrothermal synthesis method described above, and the ZnO nanorods are etched with a solution based on HCl (hydrochloric acid). (Etching) to remove. In addition, a PR provided with an empty space from which ZnO is removed may be used as a nanorod mold. Thereafter, a metal material such as Ni (nickel) is electro-deposited on the PR (ie, the nanorod mold), and the PR is removed to finally manufacture a metal nanorod made of Ni. The conductive oxide nanorods or metal nanorods may be selectively used as needed, but there may be a problem in that a cumbersome additional process may be required to manufacture the metal nanorods compared to the nanorods made of conductive oxide.

Accordingly, preferably, the nanorods 400 can use oxide as a material, and can be manufactured more easily than metal nanorods, and can provide higher strength than metal materials, so that the conductive bonding layer ( 300) may exhibit more suitable strength for insertion, and the bonding characteristics of the micro light emitting device may be further improved.

4 is a cross-sectional view illustrating a light emitting unit 200 according to an embodiment of the present invention.

Referring to FIG. 4 , each of the plurality of nanorods may include a nanorod body providing a body of the nanorod; and a metal coating layer for coating the surface of the nanorod body. When the nanorods 400 are provided as an oxide, the nanorods 400 may exhibit insufficient electrical conductivity to provide an electrical connection between the electrode parts, and thus, each of the plurality of nanorods 400 is a nanorod 400 . A metal coating layer 420 coated with a conductive metal material is provided on the body portion 410 and the surface of the nanorod body portion 410 so that sufficient conductivity can be provided. The ease of can be provided.

On the other hand, the plurality of nanorods 400 are formed on any one of the first electrode part 120 or the second electrode part 220 provided with the plurality of nanorods 400 . It may further include a seed layer 500 providing a nucleation site.

In order to provide the nanorods 400 as described above, the nanorods 400 may be formed on the electrode part by, for example, a hydrothermal synthesis method. In this case, since the electrode part may be generally a metal such as Au (gold), and the nanorod 400 may be a conductive oxide, the nanorod 400 may be formed on the electrode part due to intimacy between these dissimilar materials. may be difficult to form in

Accordingly, in order to increase the intimacy between the electrode part and the nanorods, a seed layer 500 made of a conductive metal oxide or a metal material including the same metal material as the nanorods 400 is provided, and the seed layer ( The nanorod nuclei 400 ′ may be adsorbed on 500 ) to provide a nucleation location capable of generating the nanorods 400 . Here, the conductive metal oxide seed layer 500 including the metal material of the same kind as the nanorods is, for example, when the nanorods 400 are provided as ZnO including the metal material Zn, the same metal material Zn It may be provided as AZO (Al-Zn oxide) containing, but is not particularly limited thereto.

At this time, the plurality of nanorods 400 are provided on any one of the first electrode part 120 and the second electrode part 220 to which the plurality of nanorods 400 are provided. A cover layer 600 defining a formation surface may be further included. When the nanorods 400 are provided on the seed layer 500 , the nuclei 400 ′ of the nanorods may be provided on a surface other than the seed layer 500 , and thus, it is not required. The nanorods 400 are provided even where they are not, and are electrically connected to the adjacent electrode units provided on the same layer, and errors may occur.

Therefore, a cover made of a metal material that is not the same as the metal material included in the nanorod so as to provide the nanorods 400 only where desired and to exhibit intimacy with the nanorods 400 in the electrode part. The formation surface may be defined by providing the layer 600 surrounding the edge of the formation surface on which the nanorods 400 are to be formed. The cover layer 600 may be, for example, SiO ₂ , but is not particularly limited.

In addition, since the cover layer 600 is a material that exhibits intimacy with the conductive nanorods 400, it may be an insulator, and thus, it is provided between the electrode part and other adjacent electrode parts to serve as an insulator. and it is possible to provide a more stable electrical connection.

Meanwhile, the conductive bonding layer 300 may be made of a solder material or a liquid metal. Since the conductive bonding layer 300 must be able to electrically connect the electrodes, a metal material capable of exhibiting high conductivity must be used, and a metal material having a soft property for soldering may be used. For example, a material including at least one of Sn, Ag, Cu, In, and Pb may be used.

In this case, the conductive bonding layer 300 may be made of a solder material including Sn. More preferably, the conductive bonding layer 300 may be made of a material including Au (gold) or Ag (silver) while including Sn (tin). When Sn is added to a metal material such as Au (gold) or Ag (silver) that can be used as a solder material as a material with high electrical conductivity and stability, the melting point of the alloy is lowered and castability is improved, making it hard and easy to process. Accordingly, the conductive bonding layer 300 includes Sn, and can exhibit better workability in a soldering process for flip-chip bonding the circuit unit 100 and the light emitting unit 200, and further improve the yield of the micro light emitting device. can do it

In this case, the conductive bonding layer 300 may be made of a liquid metal containing Ga. A metal material used as a material for the conductive bonding layer 300 of soldering for flip-chip bonding. Liquid metal exists in a liquid state at the operating temperature, and is free to form at high temperatures and has a thin thickness compared to strength, so it can be applied to various fields. Liquid metals may be presented. Accordingly, more preferably, among liquid metals, eutectic alloy of gallium-indium or eutectic alloy of gallium-indium-tin may be used, and the bonding property of flip-chip bonding is improved so as to more preferably exhibit sufficient conductivity and suitable softness. Since it can exhibit an appropriate softness into which the plurality of nanorods 400 can be inserted, the reliability of the micro light emitting device can be improved.

The light emitting unit 200 may further include a substrate 230 providing a laminated surface to the semiconductor laminated structure 210 . In this case, the substrate 230 is a growth substrate on which the semiconductor stacked structure 210 can be grown and stacked, or the semiconductor stacked structure 210 is temporarily supported so that the semiconductor stacked structure 210 can be transferred for flip-chip bonding. It may be a temporary substrate. In this case, the temporary substrate may be made of various organic/inorganic materials such as glass, silicon, silicon oxide, PI, PET, and PES. The growth substrate and the temporary substrate may be removed during the process, but may be provided transparently so as not to be removed.

Accordingly, the growth substrate is a substrate 230 suitable for growing a semiconductor single crystal having lattice matching, and may be formed using, for example, a transparent material including sapphire. In addition to sapphire, zinc oxide (ZnO), gallium nitride, It may be formed of (GaN), silicon carbide (SiC), aluminum nitride (AlN), silicon (Si), silicon oxide (Silicon Oxide), or the like.

In this case, a selectively removable sacrificial layer is formed on the growth substrate and the semiconductor laminate structure 210 is stacked on the formed sacrificial layer, and then the sacrificial layer is removed to form the growth substrate and the semiconductor laminate structure ( 210) may be separated. Accordingly, the light emitting unit 200 may be further miniaturized, and the light emitted from the semiconductor stacked structure 210 may be more effectively transmitted to the outside. Here, the sacrificial layer is a layer composed of an organic material that can be removed using a solvent, heat, or light energy, and various materials that can be physically removed using heat and light energy may be used.

In addition, a plurality of the switching elements 110 are provided to be two-dimensionally arranged, and the semiconductor stacked structure 210 is provided in plurality to be two-dimensionally arranged to correspond to the plurality of the switching elements 110 to form a micro LED array. Each of the plurality of semiconductor stack structures 210 may be light emitting cells of a micro LED array that can be individually flickered by a corresponding switching device 110 .

The micro light emitting device according to the embodiment of the present invention may be a micro array light emitting device in which a plurality of switching elements 110 and a plurality of semiconductor stack structures 210 are two-dimensionally arranged to form respective arrays and are individually connected to each other. In such a micro LED array, one semiconductor stacked structure 210 can function as one light emitting cell, and a desired light emitting pattern can be formed by individually flickering by the plurality of switching elements 110 .

In particular, in the micro light emitting device according to an embodiment of the present invention, by additionally providing a plurality of nanorods 400 between the plurality of switching devices 110 and the plurality of semiconductor stack structures 210, the plurality of switching devices 110 and a plurality of semiconductor laminate structures 210 are joined by a plurality of conductive bonding layers 300 provided, respectively, and are formed on any one electrode portion of the first electrode portion 120 or the second electrode portion 220 , By providing a plurality of nanorods 400 inserted into the conductive bonding layer 300 , bonding characteristics of each conductive bonding layer 300 may be further improved.

In order to improve bonding characteristics between the plurality of switching devices 110 and the plurality of semiconductor stack structures 210 provided in plurality, each of the first electrode units does not need to be controlled for each of the plurality of conductive bonding layers 400 . A plurality of nanorods 400 are respectively provided on any one electrode part of the 120 or the second electrode part 220 , and between the plurality of switching elements 110 and the plurality of semiconductor stack structures 210 . By providing such that bonding characteristics can be improved at once, it is possible to provide a micro light emitting device with improved bonding characteristics through a more convenient manufacturing method.

Here, in each of the plurality of microarrayed light emitting cells, that is, each of the plurality of semiconductor stacked structures 210 , for example, an n-type semiconductor layer 211 is present, respectively, and each unit semiconductor stacked structure 210 is electrically separated from each other. Thus, excellent electrical properties and uniform light emission can be obtained through efficient current injection. Alternatively, the plurality of semiconductor stacked structures 210 arranged in a row at one stage may share one n-type semiconductor layer 211 and minimize the spacing between the semiconductor stacked structures 210 , but is not particularly limited thereto.

A method for manufacturing a micro light emitting device according to another embodiment of the present invention includes a switching device 110 for selectively transmitting an electrical signal, and a first electrode unit 120 electrically connected to the switching device 110 . The process of preparing the circuit unit 100; A semiconductor stacked structure 210 including an n-type semiconductor layer 211 , an active layer 212 , and a p-type semiconductor layer 213 , and a second electrode part 220 electrically connected to the semiconductor stacked structure 210 . The process of preparing the light emitting unit 200 having a; forming a conductive bonding layer 300 on any one of the first electrode part 120 and the second electrode part 220; and forming a plurality of nanorods 400 on the remaining one of the first electrode part 120 and the second electrode part 220 that is not selected.

and aligning the circuit part 100 and the light emitting part 200 so that the first electrode part 120 and the second electrode part 220 face each other; and narrowing the gap between the circuit part 100 and the light emitting part 200 to at least partially insert the plurality of nanorods 400 into the conductive bonding layer 300 .

A micro light emitting device according to an embodiment of the present invention includes a circuit unit 100 including a switching element 110 selectively transmitting an electric signal, and a first electrode unit 120 electrically connected to the switching element 110 . , an n-type semiconductor layer 211 , an active layer 212 , and a semiconductor stacked structure 210 including a p-type semiconductor layer 213 , and a second electrode part 220 electrically connected to the semiconductor stacked structure 210 . ) and a conductive bonding layer 300 provided between the first electrode part 120 and the second electrode part 220 .

In addition, a plurality of nanorods 400 are provided on any one of the first electrode part 120 and the second electrode part 220 and are at least partially inserted into the conductive bonding layer 300 . may include

Among the content to be described later, while describing the micro light emitting device according to the embodiment of the present invention, content overlapping with the content described above may be omitted.

The process of preparing the circuit part 100 and the process of preparing the light emitting part 200 may be formed by, for example, a known deposition method such as chemical vapor deposition and electron beam deposition, or a process such as sputtering. Here, the lift-off method is to remove the photoresist (PR) by applying photoresist (PR), irradiating spot-shaped ultraviolet rays to the deposition area, and developing the photoresist (PR) by depositing a deposition film (or light-shielding film) such as chromium. together with the removal of the deposited film (eg, chromium, Cr, etc.) in the non-deposition area. Here, the process of preparing the circuit part 100 and the process of preparing the light emitting part 200 do not necessarily have to be sequentially performed, and may be performed simultaneously.

The process of forming the conductive bonding layer 300 is performed on one of the first electrode part 120 and the second electrode part 220 by, for example, melt of a solder material. The conductive bonding layer 300 may be formed by providing a conductive bump layer and then soldering to heat or pressurize the conductive bump layer.

In the process of forming the plurality of nanorods 400 , the nuclei 400 ′ of the nanorods are adsorbed on the other one of the first electrode part 120 or the second electrode part 220 , and, for example, For example, the plurality of nanorods 400 may be formed by growing the nanorod nuclei 400 ′ by a hydrothermal synthesis method or the like.

The process of aligning the circuit part 100 and the light emitting part 200 is a process of arranging the circuit part 100 and the light emitting part 200 in a fixed position so that they can be bonded by flip-chip bonding, for example, It may be performed by a process of sensing with a vision camera or the like so that the alignment marks provided on each of the circuit unit 100 and the light emitting unit 200 coincide. Accordingly, the circuit unit 100 and the light emitting unit 200 may be aligned to face each other.

In the process of at least partially inserting the plurality of nanorods 400 into the conductive bonding layer 300 , the circuit unit 100 may be bonded to the circuit unit 100 and the light emitting unit 200 by flip-chip bonding. ) and the conductive bonding layer 300 may be pressed by narrowing the gap between the light emitting part 200 , and in this case, heating may be provided to improve bonding properties of the conductive bonding layer 300 . Accordingly, the plurality of nanorods 400 formed on the other one of the first electrode part 120 or the second electrode part 220 may be inserted into the conductive bonding layer 300 by pressing. In addition, the bonding property between the conductive bonding layer 300 and the first electrode unit 120 or the second electrode unit 220 may be further improved.

At this time, in the process of at least partially inserting the plurality of nanorods 400 into the conductive bonding layer 300 , the process of pressing the conductive bonding layer and the process of inserting the plurality of nanorods into the conductive bonding layer does not necessarily have to be performed in time series, and may be performed simultaneously.

In addition, even if a gap occurs between the circuit part 100 and the light emitting part 200 in which the conductive bonding layer 300 is not provided, the first electrode part 120 or the first electrode part 120 or the By providing a plurality of nanorods 400 on any one electrode part of the second electrode part 220 , an electrical connection between the circuit part 100 and the light emitting part 200 is generated by the plurality of nanorods 400 . The connection can be maintained, the electrical connection between the circuit part 100 and the light emitting part 200 can be provided more reliably, and the quality of the micro light emitting device can be further improved.

5 is a diagram illustrating a process of forming a plurality of nanorods 400 using the seed layer 500 and the cover layer 600 according to another embodiment of the present invention.

Referring to FIG. 5 , in the process of forming the plurality of nanorods 400 , the plurality of nanorods 400 are formed on the other electrode part that is not selected among the first electrode part 120 and the second electrode part 220 . forming a seed layer 500 providing a nucleation location of the nanorods 400; and growing a plurality of nanorods 400 on the seed layer 500 .

In order to provide the nanorods 400 as described above, the nanorods 400 may be formed on the electrode part by, for example, a hydrothermal synthesis method. In this case, since the electrode part may be generally a metal such as Au (gold), and the nanorod 400 may be a conductive oxide, the nanorod 400 may be formed on the electrode part due to intimacy between these dissimilar materials. may be difficult to form in

Therefore, in order to increase the intimacy between the electrode part and the nanorods, a seed layer 500 including a metal material of the same kind as the nanorods 400 is provided, and the nanorod nuclei ( 400 ′) may be adsorbed to provide a nucleation site capable of generating the nanorods 400 . Here, the seed layer 500 including a metal material of the same kind as the nanorods may be provided as a material of AZO (Al-Zn oxide), for example, when the nanorods 400 are provided as ZnO, This is not particularly limited.

The process of forming the plurality of nanorods 400 is partially provided on the remaining one electrode part that is not selected among the first electrode part 120 or the second electrode part 220, so that the plurality of nanorods 400 is formed. forming a cover layer 600 defining a formation surface of the rod 400; and growing a plurality of nanorods 400 on the formation surface.

When the nanorods 400 are provided on the seed layer 500 , the nanorod nuclei 400 ′ may be provided on a surface other than the seed layer 500 . The nanorods 400 are also provided there, and they are electrically connected to the adjacent electrode units provided on the same layer, and errors may occur. Accordingly, the formation surface may be defined by providing a cover layer 600 made of a material different from that of the nanorods 400 in the electrode part so that the nanorods 400 can be provided only where desired. For example, SiO ₂ etc. can be used, but is not particularly limited.

Accordingly, the cover layer 600 made of a material different from the metal material included in the nanorods so as to provide the nanorods 400 only where desired, and to exhibit intimacy with the nanorods 400 in the electrode part. ) to surround the edge of the formation surface on which the nanorods 400 are to be formed, thereby defining the formation surface. The cover layer 600 may be, for example, SiO ₂ , but is not particularly limited.

In addition, since the cover layer 600 is a material that exhibits intimacy with the conductive nanorods 400, it may be an insulator, and thus, it is provided between the electrode part and other adjacent electrode parts to serve as an insulator. and it is possible to provide a more stable electrical connection.

During the process of forming the plurality of nanorods 400 , each of the plurality of nanorods 400 may be formed in a rod shape extending forward on the other electrode part and having a length longer than a diameter. . The smaller the diameter of the nanorods 400 is, the higher the stress applied per unit area, and the easier it is to be inserted into the conductive bonding layer 300 . However, when the diameter of the nanorods 400 is too small, it may be difficult for the nanorods 400 to withstand the applied load, which may make it difficult to be inserted into the conductive bonding layer 300 . In addition, since the nanorods 400 must be able to transfer electrons for electrical connection, if the diameter is too thin, it may be difficult to perform the electron transfer function.

In this case, the meaning that the plurality of nanorods 400 extend forward on the electrode part does not mean that the nanorods 400 extend along any one direction crossing one surface of the electrode part, and the nanorods 400 are extended forward. The rod 400 may preferably grow upward on the electrode part, but considering that they may not all grow in the same direction, it is described as extending forward. Although there are some differences, the directions may be regarded as the same within a similar range.

In addition, during the process of forming the plurality of nanorods 400 , the effective planar density of the plurality of nanorods 400 per unit area may be greater than 0% and less than or equal to 80%. At this time, when the effective area of the plurality of nanorods 400 in the total area increases too much, that is, if the density in the cross section of the plurality of nanorods 400 is higher than 80%, the nanorods 400 are one It may be difficult to act independently of each other because it is in the same state as the bulk of On the other hand, when too little of the nanorods 400 are provided, electrical conductivity may be insufficient than a required amount.

Accordingly, the effective areal density of the nanorods 400 may be preferably 80% or less, and more preferably 10% to 50%. Accordingly, each of the plurality of nanorods 400 can function independently, can be easily inserted into the conductive bonding layer 300, and can sufficiently provide electrical conductivity necessary for electrical connection between electrodes. The reliability of the connection can be improved.

Here, the planar area refers to the area in a plan view of the plurality of nanorods 400 viewed from the top as described above, and the unit planar area represents the planar area as a unit. The total area occupied by the plurality of nanorods 400 is an effective unit planar area.

The process of forming the plurality of nanorods 400 includes a process of coating a metal coating layer 410 for applying a surface of each of the plurality of nanorods 400 to each of the plurality of nanorods 400 ; can do. When the nanorods 400 are provided as oxides, the nanorods 400 may exhibit insufficient electrical conductivity to provide an electrical connection between the electrode parts. Sufficient conductivity may be provided by applying a metallic material, and reliability improvement of electrical connection, sufficient strength, and ease of manufacture may be provided.

In the micro light emitting device manufactured by the method of manufacturing a micro light emitting device according to an embodiment of the present invention, a plurality of the switching elements 110 are provided so as to be two-dimensionally arranged, and the semiconductor laminate structure 210 includes a plurality of the switching elements. Corresponding to the device 110, a plurality of are provided to be two-dimensionally arranged to form a micro LED array, and each of the plurality of semiconductor stack structures 210 is a micro that can be individually flickered by a corresponding switching device 110. It may be a light emitting cell of an LED array.

The micro light emitting device may be a micro array light emitting device in which a plurality of switching elements 110 and a plurality of semiconductor stack structures 210 are two-dimensionally arranged to form respective arrays and are individually connected to each other. In such a microarray light emitting device, one semiconductor stacked structure 210 can function as one light emitting cell, and a desired light emitting pattern can be formed by individually flickering by the plurality of switching elements 110 .

In particular, in the micro light emitting device according to an embodiment of the present invention, by providing a plurality of nanorods 400 between the plurality of switching devices 110 and the plurality of semiconductor stack structures 210, the switching device 110 and the semiconductor laminate structure 210 is connected to a plurality of connections, it is possible to further improve the connection characteristics in each of the plurality of connections, and by providing such connection characteristics to be easily controlled without controlling the plurality of each, it is possible to provide a more convenient method of manufacturing a micro light emitting device .

The meaning of "upper" or "below" used in the above description includes cases in direct contact and cases in which direct contact is not made, but is located opposite to the upper or lower portion, and is located opposite to the entire upper surface or lower surface Not only that, it is also possible to partially face each other, and it is used to mean that they face away from each other or directly contact the upper surface or the lower surface.

Although preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the above-described embodiments, and common knowledge in the field to which the present invention pertains without departing from the gist of the present invention as claimed in the claims It will be understood by those having the above that various modifications and equivalent other embodiments are possible therefrom. Accordingly, the technical protection scope of the present invention should be defined by the following claims.

100: circuit unit 110: switching element
120: first electrode part 200: light emitting part
210: semiconductor stacked structure 211: n-type semiconductor layer
212: active layer 213: p-type semiconductor layer
220: second electrode part 230: substrate
300: conductive bonding layer 400: nanorods
400`: nanorod nucleus 410: nanorod body
420: metal coating layer 500: seed layer
600: cover layer 700: underfill layer

Claims (18)

a circuit part having a switching element selectively transmitting an electric signal, and a first electrode part electrically connected to the switching element;
a light emitting unit having a semiconductor laminate structure including an n-type semiconductor layer, an active layer, and a p-type semiconductor layer, and a second electrode unit electrically connected to the semiconductor laminate;
a conductive bonding layer provided between the first electrode part and the second electrode part; and
and a plurality of nanorods provided on any one electrode part of the first electrode part or the second electrode part and inserted at least partially into the conductive bonding layer. The method according to claim 1,
The strength of each of the plurality of nanorods is equal to or greater than the strength of the conductive bonding layer. The method according to claim 1,
Each of the plurality of nanorods is a micro light emitting device having a length longer than a diameter. The method according to claim 1,
An effective planar density of the plurality of nanorods per unit area is greater than 0% and 80% or less. The method according to claim 1,
The plurality of nanorods is a micro light emitting device made of a metal material or a conductive oxide. The method according to claim 1,
Each of the plurality of nanorods,
a nanorod body providing a body of the nanorod; and
A micro light emitting device comprising a; a metal coating layer for applying the surface of the nanorod body portion. The method according to claim 1,
The micro light emission further comprising a seed layer formed on one of the first electrode part and the second electrode part to which the plurality of nanorods are provided, and providing a nucleation location of the plurality of nanorods. Device. The method according to claim 1,
The micro light emitting device further comprising a cover layer provided on any one electrode part of the first electrode part or the second electrode part on which the plurality of nanorods are provided, and defining a surface on which the plurality of nanorods are formed. . The method according to claim 1,
The conductive bonding layer is a micro light emitting device made of a solder material or liquid metal. The method according to claim 1,
The light emitting unit further comprises a substrate providing a laminated surface to the semiconductor laminated structure. The method according to claim 1,
A plurality of the switching elements are provided to be two-dimensionally arranged,
The semiconductor stacked structure is provided in plurality to correspond to the plurality of switching elements and arranged two-dimensionally to form a micro LED array,
Each of the plurality of semiconductor laminate structures is a micro light emitting device that is a unit light emitting cell of a micro LED array that can be individually flickered by a corresponding switching element. preparing a circuit unit including a switching element selectively transmitting an electrical signal and a first electrode electrically connected to the switching element;
preparing a light emitting unit having a semiconductor laminated structure including an n-type semiconductor layer, an active layer, and a P-type semiconductor layer, and a second electrode unit electrically connected to the semiconductor laminated structure;
forming a conductive bonding layer on any one of the first electrode part and the second electrode part;
forming a plurality of nanorods on the other electrode part that is not selected among the first electrode part and the second electrode part;
aligning the circuit part and the light emitting part so that the first electrode part and the second electrode part face each other; and
manufacturing a micro-light emitting device comprising a step of narrowing a gap between the circuit part and the light emitting part and bonding the first electrode part and the second electrode part while at least partially inserting the plurality of nanorods into the conductive bonding layer Way. 13. The method of claim 12,
The process of forming the plurality of nanorods,
forming a seed layer providing nucleation positions of a plurality of nanorods on the remaining one of the first electrode part and the second electrode part which is not selected; and
and growing a plurality of nanorods on the seed layer. 13. The method of claim 12,
The process of forming the plurality of nanorods,
forming a cover layer that is partially provided on the remaining one of the first electrode part and the second electrode part that is not selected among the first electrode part and the second electrode part and defines a surface for forming a plurality of nanorods; and
and growing a plurality of nanorods on the formation surface. 13. The method of claim 12,
During the process of forming the plurality of nanorods,
Each of the plurality of nanorods extends forward on the other electrode part and is formed in a rod shape having a length longer than a diameter. 13. The method of claim 12,
During the process of forming the plurality of nanorods,
An effective planar density of the plurality of nanorods per unit area is greater than 0% and 80% or less. 13. The method of claim 12,
The process of forming the plurality of nanorods,
A method of manufacturing a micro light emitting device comprising a; a process of coating a metal coating layer for applying a surface of each of the plurality of nanorods to each of the plurality of nanorods. 13. The method of claim 12,
A plurality of the switching elements are provided to be two-dimensionally arranged,
A plurality of the semiconductor stack structure is provided so as to be two-dimensionally arranged in correspondence with the plurality of switching elements to form a micro LED array,
Each of the plurality of semiconductor laminate structures is a light emitting cell of a micro LED array that can be individually flickered by a corresponding switching element.

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