KR102527857B1 - LED electrode assembly and manufacturing method thereof - Google Patents

Abstract

The present invention relates to an LED electrode assembly, and more particularly, to an LED electrode assembly capable of preventing damage and short circuit of electrodes that may occur when aligning LED elements, and a manufacturing method thereof.

Description

LED electrode assembly and manufacturing method thereof {LED electrode assembly and manufacturing method thereof}

The present invention relates to an LED electrode assembly capable of preventing electrode damage or electrical short circuit and a manufacturing method thereof.

In order to realize electronic devices using LEDs such as LED displays, bottom-up methods based on nanotechnology are being studied. However, in the electrode wiring of the LED element, when an electrode, an LED element, and another electrode are laminated in a bottom-up manner and combined in three dimensions, the LED element must be three-dimensionally erected between two different electrodes and bonded to the electrode. It may be possible if it is a size LED device, but in the case of a nano-sized LED device, it is difficult to 3-dimensionally combine upright on the electrode, and some may exist in a lying form, which may cause mounting defects.

In addition, even if the LED element can be erected on the electrode in three dimensions, there is a problem that it is difficult to couple the LED element to different electrodes one-to-one, and furthermore, even if the LED element is coupled one-to-one, it is more difficult to electrically connect without a short circuit. Such an electrical short occurs when the active layer of the LED device and the electrode come into contact with each other, and does not emit light even when power is applied, thereby causing defective light emission.

In order to solve the short-circuit problem that occurs when the active layer of the LED device touches the electrode as described above, a technology of coating an insulating film using the atomic layer deposition (ALD) method is applied to the rest of the LED device except for both ends. It was disclosed in Patent Document 1, and through this technology, it was possible to minimize the light emission failure of electronic devices. However, when the active layer of the LED element is coated with an insulating film, there is a problem in that light emitting efficiency is reduced as light that cannot escape the LED element is generated due to the insulating film. The decrease in luminous efficiency can be minimized by using an insulating film made of a transparent material, but it cannot be completely eliminated.

Meanwhile, LED elements may be self-aligned between two different electrodes by induction of an electric field formed by a potential difference between the two electrodes, and more LED elements may be aligned as the potential difference between the two electrodes increases. However, when aligning LED elements, it is difficult to align LED elements at high voltage because current flows between the two electrodes through the solvent and conductive impurities located between the two electrodes where the potential difference is formed, resulting in damage to the electrodes and electrical short circuit. there is

The present invention has been devised in view of the above points, and an object of the present invention is to provide an LED electrode assembly and a method for manufacturing the same, which prevent damage to electrodes and electrical short circuits that may occur when aligning LED elements, and exhibits more improved luminance. .

In addition, another object of the present invention is to provide a backlight unit including the LED electrode assembly according to the present invention.

In addition, the present invention has another object to provide a lamp including the LED electrode assembly according to the present invention.

An LED electrode assembly according to an embodiment for solving the above problems includes a first electrode extending in a first direction, a second electrode extending in the first direction and spaced apart in a second direction with the first electrode interposed therebetween, and A third electrode, a first LED element having a first end disposed on the second electrode, a second LED element having at least one end disposed on the third electrode, and a first LED element disposed on the second electrode A fourth electrode in contact with the first end of the element, a fifth electrode spaced apart from the fourth electrode and in contact with the second end of the first LED element and the second LED element, and spaced apart from the fifth electrode and in contact with the second LED element. and a sixth electrode in contact with the second LED element, wherein a part of outer surfaces of the first LED element and the second LED element are in contact with the first insulating layer and other parts are not in contact with the first insulating layer. .

The first LED element may have a second end disposed on the first electrode, and both ends of the second LED element may be disposed on the first electrode and the third electrode.

The fifth electrode may contact the first end of the second LED element, and the sixth electrode may contact the second end of the second LED element.

The first LED element may further include a third LED element having a second end disposed on the first electrode and a first end disposed on the third electrode.

The fifth electrode may contact the first end of the third LED element, and the sixth electrode may contact the second end of the third LED element.

It further includes a first electrode line extending in the second direction, and a second electrode line spaced apart from the first electrode line in the first direction and extending in the second direction, wherein each of the first electrodes includes the second electrode line. It may be electrically connected to the first electrode line, and the second electrode and the third electrode may be electrically connected to the second electrode line.

A distance between the first electrode and the second electrode and a distance between the first electrode and the third electrode may be smaller than lengths of the first LED element and the second LED element.

A distance between the first electrode and the second electrode may be greater than a distance between the fourth electrode and the fifth electrode.

Both ends of each of the first LED element and the second LED element are in direct contact with the first insulating layer, and may include a portion located between the both ends and not in direct contact with the first insulating layer. .

The LED element is disposed on at least one of a first semiconductor layer, a second semiconductor layer, an active layer disposed between the first semiconductor layer and the second semiconductor layer, and the first semiconductor layer and the second semiconductor layer. may include an electrode layer.

Other embodiment specifics are included in the detailed description and drawings.

According to the present invention, it is possible to implement an LED electrode assembly with excellent luminance by preventing damage to electrodes and electrical shorts that may occur when aligning LED elements. In addition, the LED electrode assembly according to the present invention can be widely applied throughout the industry, including electronic devices such as various lighting and displays.

1 is a view of an LED electrode assembly according to an embodiment of the present invention, FIG. 1(a) is a perspective view of the LED electrode assembly, and FIG. 1(b) is a vertical view along the XX′ boundary of FIG. 1(a) it is a cross section
2 is a perspective view of an LED device included in an embodiment of the present invention.
Figure 3 is a schematic diagram of the process before forming the driving electrode during the manufacturing process of the LED electrode assembly according to an embodiment of the present invention.
4 is a schematic diagram of a process of forming a driving electrode during a manufacturing process of an LED electrode assembly according to an embodiment of the present invention.
5 is a process schematic diagram according to another method of forming a driving electrode during the manufacturing process of an LED electrode assembly according to an embodiment of the present invention.
6 is an optical microscope picture of the LED electrode assembly according to Example 1.
7 is an optical micrograph of the LED electrode assembly according to Example 2.
8 is an optical micrograph of the LED electrode assembly according to Example 3.
9 is an optical micrograph of an LED electrode assembly according to Comparative Example 1.
10 is an optical micrograph of an LED electrode assembly according to Comparative Example 2.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention. This invention may be embodied in many different forms and is not limited to the embodiments set forth herein.

When arranging the LED elements, a potential difference is formed by solvent or conductive impurities located between the mounting electrodes, and current flows between the two mounting electrodes, causing an electrical short or damage to the electrodes.

The present invention is to align the LED elements by forming an insulating film on the exposed outer surfaces of the first mounting electrode (or, first electrode) and the second mounting electrode (or, second electrode) to solve the above-described problem. Electrical short circuit and damage to electrodes caused by generated solvent or conductive impurities can be prevented in advance. However, since the first mounting electrode and the second mounting electrode formed with the insulating film cannot directly contact the LED element, the first driving electrode (or the third electrode) and the second driving electrode (or, A driving LED electrode assembly can be manufactured by forming the fourth electrode).

Hereinafter, an LED electrode assembly according to an embodiment of the present invention will be described.

Referring to FIG. 1 (a), the LED electrode assembly 100 according to an embodiment of the present invention extends in a first direction and has first mounting electrodes spaced apart in a second direction different from the first direction ( 121 (or first electrode) and a second mounting electrode (122, or second electrode), an insulating film 130 formed on the first mounting electrode 121 and the second mounting electrode 122, and the first mounting electrode (121) at least one LED element 140 arranged so that one end is located on the top and the other end is located on the top of the second mounting electrode 122, and at least a portion of one end of each of the LED elements 140 is in contact with The first driving electrode 151 (or the third electrode) and the second driving electrode 152 (or the fourth electrode) contacting at least a portion of the other end may be included.

First, the first mounting electrode 121 and the second mounting electrode 122 may be formed on the substrate 110 .

Preferably, any one of a glass substrate, a quartz substrate, a sapphire substrate, a plastic substrate, and a bendable polymer film may be used as the substrate 110 . Even more preferably, the substrate may be transparent. However, it is not limited to the above types and can be used without limitation in the case of a substrate on which a conventional electrode can be formed.

The area of the substrate 110 is not limited, and the area of the first mounting electrode 121 to be formed on the substrate 110, the area of the second mounting electrode 122, the first mounting electrode 121 and It can be changed in consideration of the size of the LED elements 140 communicating with the two mounting electrodes 122 and the number of LED elements 140 communicating with each other.

In addition, the substrate may have a thickness of 100 μm to 1 mm, but is not limited thereto.

The first mounting electrode 121 is selected from the group consisting of one or more metal materials selected from the group consisting of aluminum, titanium, indium, gold, and silver, or ITO (Indium Tin Oxide), ZnO:Al, and CNT-conductive polymer composite. It may be any one or more transparent materials. When two or more types of electrode forming materials are used, the first mounting electrode 121 may have a structure in which two or more types of materials are stacked. Even more preferably, the first mounting electrode 121 may be an electrode in which two materials of titanium/gold are stacked. However, the first mounting electrode 121 is not limited to the above description.

In addition, the first mounting electrode 121 may have a width of 100 nm to 50 μm and a thickness of 0.1 to 10 μm.

The second mounting electrode 122 is selected from the group consisting of at least one metal material selected from the group consisting of aluminum, titanium, indium, gold, and silver, or ITO (Indium Tin Oxide), ZnO:Al, and CNT-conductive polymer composite. Any one or more transparent materials may be used. Preferably, the second mounting electrode 122 may have a structure in which two or more materials are stacked. Even more preferably, the second mounting electrode 122 may be an electrode in which two materials of titanium/gold are stacked. However, the second mounting electrode 122 is not limited to the above description.

In addition, the second mounting electrode 122 may have a width of 100 nm to 50 μm and a thickness of 0.1 to 10 μm.

In addition, materials forming the first mounting electrode and the second mounting electrode may be the same or different.

Next, the insulating layer 130 may be formed on the exposed outer surfaces of the first mounting electrode 121 and the second mounting electrode 122 .

In addition, the insulating film 130 can prevent an electrical short circuit occurring when an active layer of an LED element contacts a mounting electrode during alignment of the LED elements.

The thickness of the insulating film 130 may vary depending on the voltage of power applied to the first mounting electrode 121 and the second mounting electrode 122, the length of the LED element, the distance between the mounting electrodes, etc., but preferably the insulating film The silver may have a thickness of 1 nm to 100 μm.

If the thickness of the insulating film is 1 nm or less, there is a risk of electrical short circuit occurring when the active layer of the LED element contacts the mounting electrode during LED element alignment, and if it exceeds 100 μm, applied to align the LED element It may be difficult to achieve the object of the present invention, such as excessively increased voltage or misaligned LED elements.

More preferably, the insulating film may have a thickness of 1 nm to 10 μm, most preferably 1 nm to 5 μm. When the thickness range is satisfied, damage to the electrode or electrical short circuit can be prevented even at a relatively low alignment voltage, and luminance of the LED electrode assembly can be further improved by minimizing extinction by the insulating film.

In addition, the insulating film 130 may include one or more selected from the group consisting of SiO ₂ , Si ₃ N ₄ , SiN _x , Al ₂ O ₃ , HfO ₂ , Y ₂ O ₃ and TiO ₂ , and more Preferably, it may be silicon nitride (SiN _x ). However, it is not limited to the above descriptions.

Next, the LED elements 140 may be aligned so that both ends are respectively located above the first mounting electrode 121 and the second mounting electrode 122 on which the insulating film 130 is formed.

If the LED device 140 is a known LED device that can be applied to lighting, displays, etc., it may be employed without limitation. Referring to the LED element 140 with reference to FIGS. 2(a) and 2(b), the LED element 140 includes a first conductivity type semiconductor layer 141 and the first conductivity type semiconductor layer ( 141), an active layer 143 formed on the active layer, and a second conductivity-type semiconductor layer 142 formed on the active layer.

Any one of the first conductivity-type semiconductor layer 141 and the second conductivity-type semiconductor layer 142 includes at least one n-type semiconductor layer, and the other conductivity-type semiconductor layer includes at least a p-type semiconductor layer. may contain one.

x≤1, 0 ≤y≤1, 0≤x+y≤1)의 조성식을 갖는 반도체 재료 예컨대, InAlGaN, GaN, AlGaN, InGaN, AlN, InN등에서 어느 하나 이상이 선택될 수 있으며, 제1 도전형 도펀트가 도핑될 수 있다. 상기 제1 도전형 도펀트는 Si, Ge, Sn일 수 있으나, 이에 제한되지 않는다.When the first conductivity-type semiconductor layer 141 includes an n-type semiconductor layer, the n-type semiconductor layer is In _x Al _y Ga _1-xy N (0

x≤1, 0≤y≤1, 0≤x+y≤1) may be any one or more selected from semiconductor materials having a composition formula, for example, InAlGaN, GaN, AlGaN, InGaN, AlN, InN, etc. A type dopant may be doped. The first conductivity-type dopant may be Si, Ge, or Sn, but is not limited thereto.

In addition, the thickness of the first conductivity-type semiconductor layer may be 1.5 to 5 μm, but is not limited thereto.

x≤1, 0 ≤y≤1, 0≤x+y≤1)의 조성식을 갖는 반도체 물질 예컨대, InAlGaN, GaN, AlGaN, InGaN, AlN, InN등에서 어느 하나이상이 선택될 수 있으며, 제2 도전형 도펀트가 도핑될 수 있다. 상기 제2 도전형 도펀트는 Mg일 수 있으나, 이에 제한되지 않는다.When the second conductivity-type semiconductor layer 142 includes a p-type semiconductor layer, the p-type semiconductor layer is In _x Al _y Ga _1-xy N (0

x ≤ 1, 0 ≤ y ≤ 1, 0 ≤ x + y ≤ 1) may be selected from semiconductor materials having a composition formula, for example, InAlGaN, GaN, AlGaN, InGaN, AlN, InN, etc. A type dopant may be doped. The second conductivity type dopant may be Mg, but is not limited thereto.

In addition, the second conductivity-type semiconductor layer may have a thickness of 0.08 to 0.25 μm, but is not limited thereto.

The active layer 143 is formed under the first conductivity-type semiconductor layer 141 and the second conductivity-type semiconductor layer 142, and may be formed in a single or multi-quantum well structure. The active layer 143 may be used without limitation when it is an active layer included in a typical LED device used for lighting, display, and the like. When an electric field is applied to such an active layer, light is generated by electron-hole pair coupling.

In addition, the active layer 143 may have a thickness of 0.05 to 0.25 μm, but is not limited thereto.

In addition, as shown in FIG. 2B, the LED element 140 may further include a conductive electrode layer 144 formed on at least one end side of the LED element, and the conductive electrode layer is, for example, a curved outer surface. It may be a metal cap containing.

The metal cap increases the surface area of the region in which the LED device can be polarized under an electric field, so that more positive or negative charges can be charged on the surface of the metal cap, thereby improving the alignment of the LED device.

The material, shape and specific manufacturing method of the metal cap can be inserted as a reference to Patent Document 2 by the inventor of the present invention, so the present invention will omit a detailed description thereof.

The aspect ratio of the LED device 140 may be 1.2 to 100, preferably 1.2 to 50, more preferably 1.5 to 20, and even more preferably 1.5 to 10.

If the aspect ratio of the LED element 140 is less than 1.2, even if power is applied to the mounting electrodes 121 and 122, there is a concern that the LED element 140 may not be aligned. The voltage of the power supply may be lowered, but it may be difficult to manufacture the LED element 140 itself.

Next, referring to FIG. 1(b), the first driving electrode 151 and the second driving electrode 152 will be described. The first driving electrode 151 and the second driving electrode 152, the LED It does not contact the element 140 but contacts the insulating film 130, and is connected to the first parts 151a and 152a extending in the first direction and the first parts 151a and 152a, and of the LED element 140. It includes both ends and second portions 151b and 152b in contact with at least a portion of the outer surface, and the LED element 140 has a part of the outer surface in contact with the insulating film 130 and another part of the outer surface not in contact with the insulating film 130. may not be

Portions of the LED element 140 coming into contact with the first drive electrode 151 and the second drive electrode 152, respectively, are the first conductivity type semiconductor layer 141 and the second conductivity type semiconductor layer 142 or the conductive electrode layer. (144).

Next, the manufacturing method of the LED electrode assembly according to the present invention will be described.

Method for manufacturing an LED electrode assembly according to an embodiment of the present invention (1) forming an insulating film on the exposed outer surface of a mounting electrode including a first mounting electrode and a second mounting electrode formed spaced apart on the same plane step; (2) A solution containing LED elements is put on the first and second mounting electrodes on which the insulating film is formed, and the LED elements have one end positioned above the first mounting electrode and the other end positioned above the second mounting electrode. applying power to the first mounting electrode and the second mounting electrode in order to align them to a position; and (3) forming a drive electrode including a first drive electrode contacting at least a portion of one end of each of the aligned LED elements and a second drive electrode contacting at least a portion of the other end.

Alternatively, a method of manufacturing an LED electrode assembly according to an embodiment includes a first electrode and a second electrode extending in a first direction and spaced apart in a second direction different from the first direction, and the first electrode and the second electrode. Forming an insulating film on electrodes, injecting a solution containing at least one LED element on the first electrode and the second electrode on which the insulating film is formed, and applying power to the first electrode and the second electrode Arranging the LED element so that one end is located above the first electrode and the other end is located above the second electrode, and at least a portion of the third electrode and the other end contacting at least a part of one end of each of the LED elements and forming a fourth electrode in contact, wherein the third electrode and the fourth electrode do not contact the LED element but contact the insulating film and extend in the first direction; and a second portion connected to the first portion and contacting at least a portion of both ends and an outer surface of the LED device, wherein a portion of the outer surface of the LED device contacts the insulating film and another portion contacts the insulating film. may not

Prior to performing step (1) of the present invention, a step of forming a first mounting electrode and a second mounting electrode on a substrate may be performed.

The first mounting electrode and the second mounting electrode may be formed on the substrate by a known method capable of forming an electrode material on the substrate, such as a thermal evaporation method, an e-beam evaporation method, a sputtering evaporation method, and a screen printing method. . A specific method for this can be inserted into Patent Document 1 by the inventor of the present invention as a reference, the present invention will omit a detailed description thereof.

Next, referring to FIG. 3 (a), step (1) of the manufacturing method of the LED electrode assembly according to an embodiment of the present invention is the first mounting electrode 221 and the first mounting electrode 221 and the same plane This may be performed by forming an insulating film 230 on the exposed outer surface of the second mounting electrode 222 formed spaced apart from the top.

In addition, the method of forming the insulating film 230 may be any one of plasma chemical vapor deposition (PECVD), e-beam deposition, atomic layer deposition, and sputtering deposition, preferably plasma chemical vapor deposition (PECVD). However, it is not limited thereto.

Next, referring to FIG. 3(b), step (2) of the manufacturing method of the LED electrode assembly according to an embodiment of the present invention includes the first mounting electrode 221 and the second mounting electrode on which the insulating film 230 is formed. The solution 270 containing the LED elements 240 is put on the 222, and power is supplied to the first mounting electrode 221 and the second mounting electrode 222 to align the LED elements 240. It can be performed by authorizing.

In addition, the solution 270 including the LED elements may be prepared by mixing a plurality of LED elements 240 in a dispersion solvent. The dispersion solvent may be in the form of ink or paste. Preferably, the dispersion solvent may be at least one selected from the group consisting of acetone, water, alcohol, and toluene, and more preferably acetone. However, the type of dispersion solvent is not limited to the above description, and a solvent that can evaporate well without physical or chemical influence on the LED device can be used without limitation.

In addition, the LED elements 240 may be included in an amount of 0.001 to 100 parts by weight based on 100 parts by weight of the dispersion solvent. If it is included in less than 0.001 parts by weight, the normal functioning of the LED electrode assembly may be difficult because the number of LED elements communicating with the electrode is small, and there may be a problem in that a solution containing LEDs must be injected several times to overcome this, and 100 If the weight part is exceeded, there may be a problem of disturbing alignment between the plurality of LED elements 240 .

In addition, the voltage of the power applied to the first mounting electrode 221 and the second mounting electrode 222 may be 0.1 to 2000 V. If the voltage is less than 0.1 V, the alignment of the LED element may deteriorate, and if it exceeds 2000 V, leakage current such as destruction of the insulating film may occur, resulting in electrical short circuit or electrode damage.

In addition, the voltage of power applied to the first mounting electrode 221 and the second mounting electrode 222 may vary depending on the length of the LED element, the distance between the mounting electrodes, and the thickness of the insulating film.

In addition, the frequency of the power source may be 50 kHz to 1 GHz, and preferably may be an AC power source having a sine wave waveform of 90 kHz to 100 MHz.

FIG. 3(c) is a schematic diagram showing how the LED elements 240 are aligned by applying power to the first mounting electrode 221 and the second mounting electrode 222. Referring to FIG. In this way, the LED elements 240 may be arranged such that one end is located on the top of the first mounting electrode 221 and the other end is located on the top of the second mounting electrode 222. Through the insulating film 230 formed on the electrode, it is possible to prevent electrical short circuit and damage to the electrode caused by solvent or conductive impurities in advance.

Next, in step (3) of the manufacturing method of the LED electrode assembly according to an embodiment of the present invention, both ends of each of the LED elements aligned so that both ends are located on the upper portion of the first mounting electrode and the upper portion of the second mounting electrode, respectively. It may be performed by forming a first driving electrode and a second driving electrode each contacting at least a portion.

The first mounting electrode and the second mounting electrode covered with an insulating film can align the LED element by applying power, but cannot drive the LED element because they cannot electrically contact the LED element. Accordingly, the LED element may be driven by forming a first driving electrode and a second driving electrode electrically contacting the LED element.

The first driving electrode and the second driving electrode may be manufactured through a lift-off process or an etching process.

4 is a schematic diagram showing a manufacturing process of a driving electrode using a lift-off process in step (3) of the manufacturing method of an LED electrode assembly according to an embodiment of the present invention.

4(a) shows the first mounting electrode 321 and the second mounting electrode 322 formed on the substrate 310, the first mounting electrode 321 and the second mounting electrode formed on the substrate 310 ( 322) formed on the insulating film 330, and an LED element 340 arranged so that both ends are located on the upper part of the first mounting electrode 321 and the upper part of the second mounting electrode 322 on which the insulating film 330 is formed, respectively. The electrode assembly 300 is shown.

Next, a photoresist layer 360 may be formed on the LED electrode assembly 300 as shown in FIG. 4(b). A method of forming the photoresist layer 360 may be any one of spin coating, spray coating, and screen printing, preferably spin coating, but is not limited thereto.

The photoresist layer 360 may be any one selected from a positive photoresist and a negative photoresist, but it is more advantageous to simplify the process if it is preferably a negative photoresist.

Photoresist refers to a resin that undergoes chemical change when irradiated with light, and can be divided into positive photoresist and negative photoresist. Positive photoresist refers to a photosensitive resin in which the polymer is solubilized only in the portion exposed to light and the resist disappears, and negative photoresist refers to a photosensitive resin in which the polymer is insoluble only in the portion exposed to light and the resist remains.

As an example, when a negative photoresist is used, as shown in FIG. 4(c), after the photoresist layer 360 is cured, the first mounting electrode 321 ) and the space of the second mounting electrode 322, the exposed area of the photoresist layer 360 may be insolubilized by UV irradiation.

에서 1 내지 2 분 동안 열처리할 수 있다. 만일 상기 UV 조사 시간이 3초 미만일 경우, 상기 노광된 영역이 모두 불용성이 되지 않는 문제가 발생할 수 있고, 30초를 초과할 경우, 광 레지스트 층(360)의 노광 영역이 제 1 실장전극(321) 및 제 2 실장전극(322) 상부까지 확장되어 구동전극(351, 352)을 형성하기 어려울 수 있다. 다만 상기 UV 조사 시간은 조사되는 UV의 광량에 따라 다르므로 이에 제한되지 않는다. The UV irradiation may be irradiated for 3 to 30 seconds, and after the UV irradiation, 90 to 130

heat treatment for 1 to 2 minutes. If the UV irradiation time is less than 3 seconds, the exposed area may not all become insoluble, and if it exceeds 30 seconds, the exposed area of the photoresist layer 360 may be exposed to the first mounting electrode 321 ) and extending to the top of the second mounting electrode 322, it may be difficult to form the driving electrodes 351 and 352. However, the UV irradiation time is different depending on the amount of UV light to be irradiated, so it is not limited thereto.

미만이면 노광과 관계없이 현상액에 의해 광 레지스트 층이 제거되는 문제가 발생할 수 있고, 130

를 초과하면 광 레지스트 층이 과하게 고화되거나 변성되어 현상이 어려운 문제가 발생할 수 있다. In addition, the heat treatment temperature is 90

If it is less than 130, the photoresist layer may be removed by the developer regardless of exposure.

If it exceeds , the photoresist layer may be excessively hardened or denatured, resulting in difficult development.

In addition, if the heat treatment time is less than 1 minute, a problem in that the photoresist layer is removed by the developer regardless of exposure may occur, and if it exceeds 2 minutes, the photoresist layer 360 is excessively hardened or denatured, resulting in difficult development may occur.

Next, as shown in FIG. 4(d), the photoresist layer 360 may be developed to form a lift-off layer 361. Specifically, the lift-off layer 361 may be formed so that the upper portion of the first mounting electrode 321 on which the insulating film 330 is formed, the upper portion of the second mounting electrode 322, and both ends of the LED element 340 are exposed.

Any developing solution used for development may be used without limitation as long as it is a developing solution commonly used for development. Preferably, tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, and methyl hydroxide are preferred. Triethylammonium, trimethylethylammonium hydroxide, dimethyldiethylammonium hydroxide, trimethyl(2-hydroxyethyl)ammonium hydroxide, triethyl(2-hydroxyethyl)ammonium hydroxide, dimethyldi(2-hydroxyethyl)ammonium hydroxide, Diethyl(2-hydroxyethyl)ammonium hydroxide, methyltri(2-hydroxyethyl)ammonium hydroxide, ethyltri(2-hydroxyethyl)ammonium hydroxide, tetra(2-hydroxyethyl)ammonium hydroxide and potassium hydroxide ( KOH) may be used, and more preferably tetramethylammonium hydroxide (TMAH) may be used.

Next, in order to form the first driving electrode 351 and the second driving electrode 352 contacting at least a portion of both ends of each of the LED elements 340, respectively, an electrode forming material is deposited as shown in FIG. 4(e). to form the first driving electrode 351 , the second driving electrode 352 , and the third driving electrode 353 . The electrode-forming material may be deposited by any one of methods such as thermal evaporation, e-beam evaporation, sputtering evaporation, and screen printing, preferably thermal evaporation, but is not limited thereto.

In addition, the third driving electrode 353 may be removed through a lift-off layer removal process to be described later.

The electrode-forming material is selected from the group consisting of at least one metal material selected from the group consisting of aluminum, titanium, indium, gold, and silver, or ITO (Indium tin oxide), ZnO: Al, and CNT (Carbon nano tube)-conductive polymer composite. Optionally, one or more transparent materials may be used. When two or more kinds of electrode forming materials are used, the first driving electrode 351 and the second driving electrode 352 may have a structure in which two or more kinds of materials are stacked. More preferably, the first driving electrode 351 and the second driving electrode 352 may be titanium/gold electrodes in which two types of materials are stacked. However, the first driving electrode 351 and the second driving electrode 352 are not limited to the above description.

Also, preferably, the electrode-forming material may form an ohmic contact with the LED element.

In addition, materials forming the first driving electrode 351 and the second driving electrode 352 may be the same or different.

Next, as shown in FIG. 4(f), by removing the lift-off layer 361, the third driving electrode 353 formed on the lift-off layer 361 may also be removed. As a result, the first driving electrode 351 and the second driving electrode 352 contacting at least a portion of both ends of the LED element 340 may be formed.

의 광 레지스트 리무버가 담긴 용기에 5 내지 30 분 동안 넣어서 수행할 수 있다. 만일 온도가 55

미만이면 광 레지스트 리무버의 반응성이 낮기 때문에 리프트오프층 (361)이 완전히 제거되지 않는 문제가 발생할 수 있고, 온도가 75

를 초과하면 LED 소자(340) 및 구동전극(361, 362)에 결함이 발생하는 등 본 발명의 목적을 달성하기에 어려울 수 있다. 또한, 5분 미만으로 수행할 경우 리프트오프층(361)이 완전히 제거되지 않는 문제가 발생할 수 있고, 30분을 초과할 경우 LED 소자 (340) 및 구동전극(351, 352)에 결함이 발생하는 등 본 발명의 목적을 달성하기에 어려울 수 있다.In addition, the lift-off layer 361 may be removed by putting it in a container containing a photoresist remover. Specifically, 55 to 75

It can be performed by putting it in a container containing a photoresist remover for 5 to 30 minutes. If the temperature is 55

If it is less than 75°C, the lift-off layer 361 may not be completely removed because the reactivity of the photoresist remover is low.

If it exceeds, it may be difficult to achieve the object of the present invention, such as defects occurring in the LED element 340 and the driving electrodes 361 and 362. In addition, if it is performed for less than 5 minutes, a problem may occur in that the lift-off layer 361 is not completely removed, and if it exceeds 30 minutes, defects may occur in the LED element 340 and the driving electrodes 351 and 352. etc. may be difficult to achieve the object of the present invention.

The photoresist remover can be used without limitation as long as it is a commonly used photoresist remover, and preferably 2-(2-aminoethoxy) (2-(2-Aminoethoxy)), ethanol, hydroxylamine ( hydroxylamine) and catechol (EKC 265 polymer, DuPont), acetone, N-methylpyrrolidone (1-Methyl-2-pyrrolidone, NMP), dimethyl sulfoxide (Dimethyl sulfoxide, DMSO) Any one selected may be used, and more preferably, EKC 265 polymer may be used.

5 is a schematic diagram showing a manufacturing process of a driving electrode using an etching process in step (3) of the manufacturing method of an LED electrode assembly according to an embodiment of the present invention.

First, FIG. 5(a) shows the first mounting electrode 421 and the second mounting electrode 422 formed on the substrate 410, the first mounting electrode 421 and the second mounting electrode 421 formed on the substrate 410. An insulating film 430 formed on the electrode 422, and an LED element 440 aligned so that both ends are located on the upper part of the first mounting electrode 421 and the upper part of the second mounting electrode 422 on which the insulating film 430 is formed, respectively. It shows the LED electrode assembly 400 to do.

Next, as shown in FIG. 5(b), an electrode forming material may be deposited on the LED electrode assembly 400 to form a driving electrode layer 450.

The electrode-forming material may be deposited by any one of methods such as a thermal evaporation method, an e-beam evaporation method, a sputtering evaporation method, and a screen printing method, and may be preferably a thermal evaporation method, but is not limited thereto.

Next, a photoresist layer 460 may be formed on the driving electrode layer 450 as shown in FIG. 5(c). A method of forming the photoresist layer 460 may be any one of spin coating, spray coating, and screen printing, preferably spin coating, but is not limited thereto.

The photoresist layer 460 may be any one selected from a positive photoresist and a negative photoresist, but it is more advantageous to simplify the process if it is preferably a positive photoresist.

As an example, when a positive photoresist is used, as shown in FIG. 5(d), after the photoresist layer 460 is cured, a first mounting electrode ( 421) and the second mounting electrode 422, the exposed area of the photoresist layer 460 can be solubilized by forming a mask 470 corresponding to the space of the second mounting electrode 422 and irradiating UV with a direct lithography method. The UV irradiation may be irradiated for 0.5 to 30 seconds, preferably for 2 to 15 seconds. If the UV irradiation time is less than 0.5 seconds, the exposed area may not all be soluble, resulting in a problem of not forming a pattern. If the UV irradiation time exceeds 30 seconds, the exposed area is expanded to form a driving electrode in an etching process described later. It may be difficult to achieve the object of the present invention, such as being excessively removed.

Next, as shown in FIG. 5(e), the exposed area of the photoresist layer may be developed. When the exposed area is developed, the first photoresist layer 461 and the second photoresist layer 462 are formed to correspond to the spaces of the first mounting electrode 421 and the second mounting electrode 422 . The reason why only a part of the photoresist layer is developed is that the driving electrodes 451 and 452 corresponding to the spaces of the first mounting electrode 421 and the second mounting electrode 422 are not etched in an etching process described later, and the photoresist This is to remove only a part of the driving electrode 453 exposed by the development of the layer.

Meanwhile, in the case of forming the positive photoresist layer, the development time may be 15 to 75 seconds, preferably 30 to 60 seconds. If the development time is less than 15 seconds, the photoresist layer 460 may not develop well, and if it exceeds 75 seconds, the photoresist layer 460 is excessively developed, resulting in loss of the driving electrode in the etching process described later. It may be difficult to achieve the object of the present invention, such as excessive removal.

Next, as shown in FIG. 5(f), a portion of the driving electrode 453 exposed by the development of the photoresist layer may be removed through an etching process. Through the etching process, the first driving electrode 451 and the second driving electrode 452 are formed to correspond to the spaces of the first mounting electrode 421 and the second mounting electrode 422 .

The etching process can be used without limitation as long as it is a method commonly used for metal etching, preferably a dry etching method and a wet etching method, and more preferably using a dry etching method to etch in a certain direction. It is advantageous. In addition, the dry etching can be used without limitation as long as it is a gas commonly used for dry etching, preferably any one gas selected from CF ₄ and Cl ₂ can be used, and in the case of using CF ₄ , 40 to 120 sccm , 90 to 110 W and 0.040 to 0.070 Torr, and when using Cl ₂ , it can be performed under conditions of 10 to 30 sccm, 70 to 90 W and 0.06 to 0.1 Torr.

Next, as shown in FIG. 5 (g), the photoresist layers 461 and 462 on the first driving electrode 451 and the second driving electrode 452 are removed to manufacture an LED electrode assembly having a driving electrode formed thereon. there is.

The first photoresist layer 461 and the second photoresist layer 462 on the first driving electrode 451 and the second driving electrode 452 are removed by putting them in a container containing a photoresist remover. can do.

의 광 레지스트 리무버가 담긴 용기에 5 내지 30 분 동안 넣어서 수행할 수 있다. 만일 온도가 55

미만이면 광 레지스트 리무버의 반응성이 낮기 때문에 광 레지스트층(461, 462)이 완전히 제거되지 않는 문제가 발생할 수 있고, 온도가 75

를 초과하면 LED 소자(440) 및 구동전극(451, 452)에 결함이 발생하는 등 본 발명의 목적을 달성하기에 어려울 수 있다. 또한, 5분 미만으로 수행할 경우 광 레지스트층(461, 462)이 완전히 제거되지 않는 문제가 발생할 수 있고, 30분을 초과할 경우 LED 소자 (440) 및 구동전극(451, 452)에 결함이 발생하는 등 본 발명의 목적을 달성하기에 어려울 수 있다.specifically 55 to 75

It can be performed by putting it in a container containing a photoresist remover for 5 to 30 minutes. If the temperature is 55

If the temperature is less than 75°C, the photoresist layer 461 and 462 may not be completely removed because the reactivity of the photoresist remover is low.

If it exceeds, it may be difficult to achieve the object of the present invention, such as defects occurring in the LED element 440 and the driving electrodes 451 and 452. In addition, if it is performed for less than 5 minutes, a problem may occur in that the photoresist layers 461 and 462 are not completely removed, and if it exceeds 30 minutes, defects in the LED element 440 and the driving electrodes 451 and 452 may occur. It may be difficult to achieve the object of the present invention, such as occurs.

The photoresist remover can be used without limitation as long as it is a commonly used photoresist remover, and preferably 2-(2-aminoethoxy) (2-(2-Aminoethoxy)), ethanol, hydroxylamine ( hydroxylamine) and catechol (EKC 265 polymer, DuPont), acetone, N-methylpyrrolidone (1-Methyl-2-pyrrolidone, NMP), dimethyl sulfoxide (Dimethyl sulfoxide, DMSO) Any one selected may be used, and more preferably, EKC 265 polymer may be used.

On the other hand, the present invention includes a lamp including the LED electrode assembly according to the present invention described above. The lamp may further include a support for accommodating or supporting the LED electrode assembly. The support may be used without limitation in the case of a support commonly used in an LED lamp, but may be preferably any one material selected from the group consisting of organic resin, ceramic, metal, and inorganic resin, and the material may be transparent or opaque. there is. In addition, the shape of the support body may be a cup shape or a flat plate shape, but is not limited thereto, and since the shape of the support body may be designed differently according to the purpose, the present invention is not particularly limited to the shape of the support body. When the support has the shape of a cup, the internal volume can be variously changed in proportion to the size and density of electrodes on which the LED elements are arranged. Also, the internal volume of the support may vary according to the thickness of the support. The thickness of the support may be the same at all points of the support or may be different at some points. The thickness of the support may be designed differently depending on the purpose, and is not particularly limited in the present invention.

In addition, the lamp may further include a phosphor provided inside the support and excited by light irradiated from the LED device. For example, when the LED device is a UV LED device, the phosphor excited by UV may be any one of blue, yellow, green, amber, and red phosphors, and at this time, a single color emitting light of any selected color. It can be an LED lamp. Also, preferably, the phosphor excited by UV may be at least one of blue, yellow, green, amber, and red, and more preferably blue/yellow, blue/green/red, and blue/green/amber/red. It may be any one kind of mixed phosphor, and in this case, white light may be irradiated by the phosphor. As a specific phosphor can be used by selecting a known phosphor in consideration of the light color emitted by the selected LED element, a detailed description thereof will be omitted in the present invention.

In addition, the present invention can provide a backlight unit including the LED electrode assembly according to the present invention.

Specifically, the light-receiving display may include a backlight unit, a display panel disposed above the backlight unit, and a support member supporting and accommodating the backlight unit and the display panel. At this time, the backlight unit further includes at least one LED electrode assembly capable of supplying light to the display panel and a reflective member disposed below the LED electrode assembly and reflecting incident light toward the display panel on which an image is displayed, The LED electrode assembly may further include an optical sheet that transmits only linearly polarized light in one specific direction (or reflects linearly polarized light in another direction) of light emitted from the LED electrode assembly. Each configuration of the backlight unit and the light-receiving display may employ a configuration known in the display field, and thus a detailed description thereof is omitted in the present invention.

In addition, the LED electrode assembly according to an embodiment of the present invention described above can be applied to a color-by-blue LED display.

At least one of the LED electrode assemblies may form a sub-pixel or unit pixel. When the LED element provided in the LED electrode assembly is a single-color LED element, for example, a blue LED element, the LED display has a red and green color conversion layer formed on top of a sub-pixel or unit pixel provided with the LED electrode assembly. It may be further provided, through which a color-by-blue LED display may be implemented. As other configurations of the color-by-blue LED display may employ known configurations of LED displays, detailed descriptions thereof are omitted in the present invention.

In addition, the LED electrode assembly according to one embodiment of the present invention described above can be applied to a full-color LED display.

At least one of the LED electrode assemblies may form a sub-pixel or unit pixel. For example, an LED electrode assembly having an LED element of any one color among a blue LED element, a red LED element, and a green LED element is configured to configure a unit pixel that emits red, green, and blue colors for each sub-pixel to implement white light. It can be placed in a sub-pixel defined to represent , and through this, a full-color LED display can be implemented. As other configurations of the full-color LED display may employ known configurations of LED displays, detailed description thereof is omitted in the present invention.

(Example 1)

A mounting electrode including a first mounting electrode and a second mounting electrode was formed on a quartz substrate having a thickness of 500 μm. At this time, the width of the mounting electrode is 3 μm, the thickness is 0.2 μm, the material is titanium/gold, and the interval between the first mounting electrode and the adjacent second mounting electrode is 2.7 μm.

A silicon nitride insulating film was formed on the mounting electrode by a plasma chemical vapor deposition method. The thickness of the insulating film was 200 nm based on the upper surface of the mounting electrode.

Then, a solution containing LED elements was prepared by mixing 1.0 parts by weight of LED elements having specifications as shown in Table 1 below with respect to 100 parts by weight of acetone.

division texture Height (μm) Diameter (μm) conductive electrode layer chrome 0.03 0.5 1st conductivity type semiconductor layer n-GaN 2.67 0.5 active layer InGaN 0.1 0.5 Second conductivity type semiconductor layer p-GaN 0.2 0.5 LED element - 3.0 0.5

The prepared solution was dropped on the substrate on which the mounting electrodes were formed, and power supply having a voltage of 100 V _pp and a frequency of 950 kHz was applied to the mounting electrodes for 1 minute to align the LED elements. A driving electrode including a first driving electrode contacting at least a portion of one end of each of the LED elements arranged on the mounting electrode having an insulating film and a second driving electrode contacting at least a portion of the other end was formed. At this time, the drive electrode has a width of 3 μm, a thickness of 0.2 μm, a material of titanium/gold, and a distance between the first drive electrode and the adjacent second drive electrode is 2.7 μm. (Example 2)

It was carried out in the same manner as in Example 1, but a voltage of 60 V _pp and a frequency of 950 kHz were applied to the mounting electrode for 1 minute to align the LED elements.

(Example 3)

In the same manner as in Example 1, an insulating film having a thickness of 1000 nm was formed based on the upper surface of the mounting electrode.

(Comparative Example 1)

It was manufactured in the same manner as in Example 1, but the LED elements were aligned by applying power to the mounting electrode without forming an insulating film, and an LED electrode assembly was manufactured without forming a driving electrode.

(Comparative Example 2)

It was manufactured in the same manner as in Example 2, but power was applied to the mounting electrodes without forming an insulating film to align the LED elements, and an LED electrode assembly was manufactured without forming a driving electrode.

(Experimental Example 1)

For the LED electrode assemblies prepared in Examples and Comparative Examples, the number of light emission of the LED element was observed through an optical microscope, and the number was counted and shown in Table 2 below.

insulating film
Thickness (nm) Voltage (V _PP ) Frequency (kHz) LED element
number of lights Light amount (%) Example 1 200 100 950 41565 41565/41565=100 Example 2 200 60 950 28156 28156/41565=68 Example 3 1000 100 950 31850 31850/41565=77 Comparative Example 1 - 100 950 5587 5587/41565=13 Comparative Example 2 - 60 950 5174 5174/41565=12

In Table 2, “emission number” refers to the number of LED elements emitting blue light when power is applied to the LED electrode assembly, and “light amount (%)” refers to the number of LED elements emitting blue light, in Example 1. It is a relative ratio when set to 100.

*143 First, comparing Comparative Example 1 and Comparative Example 2, as shown in FIG. 10, Comparative Example 2 to which 60V _pp power was applied did not cause electrode damage, but referring to FIG. 9, 100V _pp power was applied In Comparative Example 1, electrode damage occurred. In addition, there was no significant difference in the amount of light between Comparative Example 1 and Comparative Example 2, and through this, it can be seen that the LED electrode assembly without an insulating film cannot greatly increase the number of actually emitting elements even if the alignment voltage is increased.

Next, comparing Example 1 and Comparative Example 1, Example 1 having an insulating film, as shown in FIG. 6, did not cause damage to the electrode even when a power of 100V _pp was applied, and It can be seen that the number of light emission is significantly higher than that of Comparative Example 1.

Next, Example 1 and Example 2 had an insulating film having the same thickness, and as shown in FIGS. 6 and 7, no damage to the electrode occurred. In addition, Example 1 to which a relatively high voltage was applied was observed to have a higher number of luminescence than Example 2.

Next, in Example 1 and Example 3, power of the same voltage was applied to align the LED elements, and as shown in FIGS. 6 and 8, no electrode damage occurred. In addition, Example 3 having a relatively thick insulating film was observed to have a lower number of light emission than Example 1, which is considered to be because the effect of the magnetic field aligning the LED elements decreased as the thickness of the insulating film became thicker. As shown in FIG. 8 , it can be seen that some of the LED elements mounted in Example 3 are located only on top of one of the first mounting electrode and the second mounting electrode. In this way, when both ends of the LED element are not located above the first mounting electrode and the second mounting electrode, respectively, the LED element may not emit light even if the driving electrode is formed.

Although one embodiment of the present invention has been described above, the spirit of the present invention is not limited to the embodiments presented herein, and those skilled in the art who understand the spirit of the present invention may add elements within the scope of the same spirit. However, other embodiments can be easily proposed by means of changes, deletions, additions, etc., but these will also fall within the scope of the present invention.

100: LED electrode assembly
110, 210, 310, 410: substrate
121, 221, 321, 421: first mounting electrode
122, 222, 322, 422: second mounting electrode
130, 230, 430: insulating film
140, 240, 340, 440: LED element
141: first conductivity type semiconductor layer
142: second conductivity type semiconductor layer
143: active layer
144, 145: conductive electrode layer
151, 351, 451: first driving electrode
152, 352, 452: second driving electrode
151a: first portion of first drive electrode
152a: first part of second drive electrode
151b: second part of the first drive electrode
152b: second part of second drive electrode
270: solution containing an LED element
350, 450, 453: driving electrode layer
353: third driving electrode layer
360, 460, 461, 462, 463: photoresist layer
361: lift-off layer
370, 470: mask

Claims (10)

a first electrode extending in a first direction;
a plurality of second electrodes extending in the first direction and spaced apart in a second direction with the first electrode interposed therebetween;
a first insulating layer disposed on the first electrode and the plurality of second electrodes;
a first LED element having a first end disposed on one of the second electrodes on the first insulating layer;
a second LED element having at least one end disposed on the other one of the second electrodes on the first insulating layer;
a first driving electrode disposed on one of the second electrodes and contacting the first end of the first LED element;
a second driving electrode spaced apart from the first driving electrode and contacting a second end of the first LED element and the second LED element; and
A third driving electrode spaced apart from the second driving electrode and contacting the second LED element,
Some of the outer surfaces of the first LED element and the second LED element are in contact with the first insulating layer and other parts are not in contact with the first insulating layer,
The first driving electrode, the second driving electrode and the third driving electrode,
A first portion extending in the first direction without contacting the first LED element and the second LED element, and
LED electrode assembly comprising a second part connected to the first part and contacting at least a part of both ends and an outer surface of the first LED element or the second LED element. According to claim 1,
The first LED element has a second end disposed on the first electrode,
The second LED element has both ends disposed on the other one of the first electrode and the second electrode. According to claim 2,
The second driving electrode is in contact with the first end of the second LED element,
The third driving electrode is LED electrode assembly in contact with the second end of the second LED element. According to claim 1,
The first LED element has a second end disposed on the first electrode,
The LED electrode assembly further comprising a third LED element having a first end disposed on the other one of the second electrodes. delete According to claim 1,
a first electrode line extending in the second direction; and
Further comprising a second electrode line spaced apart from the first electrode line in the first direction and extending in the second direction,
Wherein each of the first electrodes is electrically connected to the first electrode line, and each of the plurality of second electrodes is electrically connected to the second electrode line. According to claim 1,
A distance between the first electrode and any one of the second electrodes and a distance between the first electrode and the other of the second electrodes are smaller than the lengths of the first LED element and the second LED element. LED electrode assembly. According to claim 1,
The distance between the first electrode and any one of the second electrodes is greater than the distance between the first drive electrode and the second drive electrode LED electrode assembly. According to claim 1,
Both ends of the first LED element and the second LED element are in direct contact with the first insulating layer, respectively, and the LED electrode includes a portion located between the both ends and not in direct contact with the first insulating layer. assembly. According to claim 1,
The LED element is disposed on at least one of a first semiconductor layer, a second semiconductor layer, an active layer disposed between the first semiconductor layer and the second semiconductor layer, and the first semiconductor layer and the second semiconductor layer. LED electrode assembly comprising an electrode layer.

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