JP2009038331A - Method for electrically connecting element to wiring, method for manufacturing light-emitting element assembly, and light-emitting element assembly - Google Patents

Abstract

Provided is a method for electrically connecting an element to a wiring, which can securely fix the element by using a conductive adhesive layer on the wiring.
An electrical connection method includes forming a conductive fixing member precursor layer on at least a wiring 41 provided on a base body 40, and then connecting the element including the connection portion 25 to the conductive portion 25. After placing the conductive fixing member precursor layer 42 on the wiring 41 so as to be in contact with the conductive fixing member precursor layer 42, the conductive fixing member precursor layer 42 is heated to obtain the conductive fixing member layer 43. Thus, the conductive fixing member precursor layer 42 is made of a solution-type conductive material.
[Selection] Figure 7

Description

  The present invention relates to a method for electrically connecting elements to wiring, a method for manufacturing a light emitting element assembly, and a light emitting element assembly.

  At present, for example, anisotropic conductive paste (ACP) is often used as a method of electrically connecting a light emitting element to a wiring or the like (see, for example, JP-A-11-177148 or JP-A-2004-215223). An anisotropic conductive paste is generally composed of conductive particles, a binder, and a solvent. After application, the light-emitting element can be electrically connected to a wiring or the like by drying and thermocompression bonding.

JP-A-11-177148 JP 2004-215223 A JP 2000-315453 A

  However, when the element such as the light emitting element is about several tens of μm or less, the size of the conductive particles contained in the anisotropic conductive paste relative to the element becomes relatively large. ) Or as schematically shown in FIG. 13B, there arises a problem that the element and the wiring cannot be reliably electrically connected, or that the element is inclined on the wiring. . There is also a problem that when the unnecessary anisotropic conductive paste is removed, the binder tends to remain as a residue. Furthermore, since it is necessary to apply pressure while applying an external stimulus such as temperature and light when using the anisotropic conductive paste, it is difficult to uniformly fix minute elements to the wiring.

  A technique for fixing a cathode material made of isotropic carbon to a substrate using ITO ink is disclosed in Japanese Patent Laid-Open No. 2000-315453. However, in the technique disclosed in Japanese Patent Laid-Open No. 2000-315453, after the isotropic carbon is fixed to the substrate with ITO ink, patterning is performed using a resist as an etching mask, and unnecessary isotropic carbon is obtained. In addition, complicated operations such as removing ITO ink are required.

  Accordingly, an object of the present invention is to fix an element or a light emitting element on a wiring formed on a substrate using a fixing conductive layer in a state where the element or the light emitting element is securely electrically connected. A method of electrically connecting elements to wiring that does not require complicated operations such as patterning the conductive layer using the etching mask as a mask, and a method of manufacturing a light emitting element assembly to which the electrical connection method is applied, Another object of the present invention is to provide a light emitting device assembly to which such an electrical connection method is applied.

In order to achieve the above object, a method of electrically connecting an element to a wiring according to the first aspect of the present invention includes:
(A) forming a conductive fixing member precursor layer on at least the wiring provided on the substrate;
(B) After disposing the element provided with the connection portion on the wiring so that the connection portion is in contact with the conductive fixing member precursor layer, the conductive fixing member precursor layer is heated to form the conductive fixing member layer. By obtaining, fixing the connection portion of the element to the wiring through the conductive fixing member layer,
Consisting of processes,
The conductive fixing member precursor layer is made of a solution-type conductive material.

In order to achieve the above object, a method for manufacturing a light-emitting element assembly according to the first aspect of the present invention includes:
(A) forming a conductive fixing member precursor layer on at least the wiring provided on the substrate;
(B) A light emitting element having a connection portion is arranged on the wiring so that the connection portion is in contact with the conductive fixing member precursor layer, and then the conductive fixing member precursor layer is heated to form a conductive fixing member layer. By fixing the connection part of the light emitting element to the wiring through the conductive fixing member layer,
Consisting of processes,
The conductive fixing member precursor layer is made of a solution-type conductive material.

In order to achieve the above object, the electrical connection method of the element to the wiring according to the second aspect of the present invention includes:
(A) forming a conductive fixing member precursor layer on the connection portion provided in the element;
(B) By arranging the element on the wiring so that the conductive fixing member precursor layer is in contact with the wiring provided on the substrate, the conductive fixing member precursor layer is heated to obtain the conductive fixing member layer. Fixing the connection portion of the element to the wiring through the conductive fixing member layer,
Consisting of processes,
The conductive fixing member precursor layer is made of a solution-type conductive material.

A method for manufacturing a light-emitting element assembly according to the second aspect of the present invention for achieving the above object is as follows:
(A) A conductive fixing member precursor layer is formed on the connection portion provided in the light emitting element, and then
(B) After arranging the light emitting element on the wiring so that the conductive fixing member precursor layer is in contact with the wiring provided on the substrate, the conductive fixing member precursor layer is heated to obtain the conductive fixing member layer. Then, the connection part of the light emitting element is fixed to the wiring through the conductive fixing member layer.
Consisting of processes,
The conductive fixing member precursor layer is made of a solution-type conductive material.

To achieve the above object, a light emitting device assembly according to a first aspect of the present invention comprises:
The connection part of the light emitting element and the wiring formed on the base are fixed by the conductive fixing member layer,
There is a conductive fixing member layer only below the light emitting element,
The conductive fixing member layer is made of ITO or IZO.

A light emitting device assembly according to the second aspect of the present invention for achieving the above object is
The connection part of the light emitting element and the wiring formed on the base are fixed by the conductive fixing member layer,
The conductive fixing member layer is composed of at least metal atoms, carbon (C) atoms, and oxygen (O) atoms.

  In the light-emitting element assembly according to the second aspect of the present invention, the conductive fixing member layer is composed of metal atoms, carbon (C) atoms, and oxygen (O) atoms. Here, carbon (C) Examples of the proportion of atoms include 3% by weight to 30% by weight.

  The metal atom includes, for example, indium (In), tin (Sn), zinc (Zn), a combination of indium (In) and tin (Sn), and a combination of indium (In) and zinc (Zn). Furthermore, metalloid atoms, semiconductor atoms, and combinations thereof are included. In addition to the metal atoms, carbon (C) atoms, and oxygen (O) atoms, the atoms constituting the conductive fixing member layer can include hydrogen (H) atoms.

A method for electrically connecting an element to a wiring according to the first aspect of the present invention or a method for manufacturing a light emitting element assembly according to the first aspect of the present invention (hereinafter collectively referred to as “the present invention”). In the case of “the method according to the first aspect”),
In the step (A), a conductive fixing member precursor layer is formed on the substrate including the wiring,
After the step (B), the conductive fixing member layer located below the element or the light emitting element (hereinafter collectively referred to as “element etc.”) is left, and other conductive fixing member layers It can be set as the structure including the process of removing this part.

  In the method according to the first aspect of the present invention including the above preferable configuration, in the step (B), a form supported on the substrate (a form formed on the substrate, a form held on the substrate). In a state where the connection portion provided in the element or the like is in contact with the conductive fixing member precursor layer, the element or the like is removed from the substrate, whereby the element or the like can be arranged on the wiring.

  A method for electrically connecting an element to a wiring according to the second aspect of the present invention or a method for manufacturing a light emitting element assembly according to the second aspect of the present invention (hereinafter collectively referred to as “the present invention”). In the step (B), it is supported on the substrate (including a form formed on the substrate and a form held on the substrate). The element etc. is arranged on the wiring by removing the element etc. from the substrate in a state where the conductive fixing member precursor layer formed on the connection portion provided in the element etc. is in contact with the wiring provided on the base. It can be set as a form to do. In this case, it is preferable that the step of forming the conductive fixing member precursor layer on the connection portion provided in the element or the like is after the element or the like is supported on the substrate.

The method according to the first aspect of the present invention including the preferred configurations and forms described above or the method according to the second aspect of the present invention (hereinafter collectively referred to as “the method of the present invention”) In some cases, the conductive fixing member precursor layer preferably does not contain fine particles having a particle size exceeding 1 × 10 ⁻⁷ m. By not containing fine particles having a particle size exceeding 1 × 10 ⁻⁷ m, it is possible to securely connect the element and the wiring to each other, or the element is inclined on the wiring. Can be reliably prevented.

  Further, the method of the present invention including the above-described preferred configuration, the light emitting element assembly according to the first aspect or the second aspect of the present invention (hereinafter, these light emitting element assemblies are collectively referred to as “the present invention”). In the present invention, the conductive fixing member layer can be made of ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide), but is not limited thereto. It can also be comprised from the electrically-conductive material obtained by using a metal alkoxide, a metal complex, and a metal salt as a starting material.

  Further, in the method of the present invention including the various preferable configurations described above, the metal and the conductive material constituting the wiring are subjected to heat treatment during the step (B) or after the step (B). Alloying with the metal constituting the fixing member layer, or alloying between the metal constituting the connection part of the element and the metal constituting the conductive fixing member layer, or the metal constituting the wiring and the conductive fixing member Alloying with the metal constituting the layer and alloying between the metal constituting the connection part of the element and the metal and the metal constituting the conductive fixing member layer can be achieved, thereby further stabilizing the wiring. And a connection portion such as an element can be obtained, and long-term reliability of a connection portion such as an element or a wiring portion can be improved. Further, when removing a part of the conductive fixing member layer, by alloying, the portion between the alloyed conductive fixing member layer portion and the non-alloyed conductive fixing member layer portion is formed. Thus, for example, since the etching selectivity can be changed, a part of the conductive fixing member layer can be easily removed. Examples of such metals include silver (Ag), gold (Au), indium (In), tin (Sn), and copper (Cu), or an alloy containing these metals, An alloy made of any one of metals such as [Al, Mo, Ni, Pb, Pd] can be exemplified. In this case, a metal layer for alloying may be formed in the region of the projected image of the element or the like vertically projected onto the substrate. The outer edge of the projected image of the element or the like vertically projected on the substrate may coincide with the outer edge of the metal layer, or the outer edge of the metal layer may be included in the outer edge of the projected image. In some cases, the outer edge of the metal layer may be included in the outer edge of the metal layer. In this case, the area surrounded by the outer edge of the metal layer is set to “1” in consideration of manufacturing variations. The area of the region surrounded by the outer edge of the projected image is preferably “0.80 to 0.99”. Examples of the metal constituting the metal layer include silver (Ag), gold (Au), indium (In), tin (Sn), and titanium (Ti), or an alloy containing these metals. Can be illustrated. Similarly, in the light emitting element assembly of the present invention, the metal constituting the wiring and the metal constituting the conductive fixing member layer are alloyed, or the metal constituting the connecting portion of the light emitting element is conductively fixed. Alloying with the metal constituting the member layer, or alloying between the metal constituting the wiring and the metal constituting the conductive fixing member layer and the metal constituting the connecting portion of the light emitting element and the conductive fixing member layer It is preferable that alloying with the metal to be performed is performed. The metal layer may be formed on the wiring, or may be formed between the base and the wiring. The heat treatment for alloying may be referred to as “alloying heat treatment” for convenience.

Examples of the substrate in the method of the present invention or the light emitting device assembly of the present invention include glass substrates, metal substrates and metal sheets, alloy substrates and alloy sheets, ceramic substrates and ceramic sheets, semiconductor substrates, plastic substrates, plastic sheets and plastic films. can do. Examples of the plastic film include polyethersulfone (PES) film, polyethylene naphthalate (PEN) film, polyimide (PI) film, and polyethylene terephthalate (PET) film. Alternatively, examples of the substrate include those in which the above-mentioned various films are bonded to a glass substrate, and those in which a polyimide resin layer, an acrylic resin layer, a polystyrene resin layer, and a silicone rubber layer are formed on the glass substrate. Further, the glass substrate may be replaced with a metal substrate or a plastic substrate. Alternatively, an insulating film may be formed on the surface of these substrates. Here, as a material constituting the insulating film, not only a silicon oxide material, silicon nitride (SiN _Y ), an inorganic insulating material exemplified by a metal oxide high dielectric insulating film, but also polymethyl methacrylate (PMMA), Examples thereof include organic insulating materials exemplified by polyvinyl phenol (PVP) and polyvinyl alcohol (PVA), and combinations thereof can also be used. Silicon oxide-based materials include silicon oxide (SiO _x ), silicon oxynitride (SiON), SOG (spin-on-glass), low dielectric constant SiO _x -based materials (for example, polyaryl ether, cycloperfluorocarbon polymer, and benzocyclobutene). , Cyclic fluororesin, polytetrafluoroethylene, fluorinated aryl ether, fluorinated polyimide, amorphous carbon, and organic SOG). Examples of the method for forming the insulating film include various PVD methods described later; various CVD methods; spin coating methods; various printing methods and various coating methods described later; immersion methods; casting methods; and spray methods. it can.

  The wiring pattern formed on the substrate may be appropriately determined based on the required specifications. For example, the wiring pattern may be constituted by a plurality of wirings extending in a strip shape, or, for example, a trunk wiring, and It may be configured by a plurality of branch wirings extending from the trunk wiring, and an element or the like may be fixed on the branch wiring. As a material constituting the wiring formed on the substrate, the above-described silver (Ag), gold (Au), indium (In), tin (Sn), copper (Cu), alloys containing these metals, [Al, Mo , Ni, Pb, and Pd], as well as aluminum (Al), palladium (Pd), platinum (Pt), chromium (Cr), nickel (Ni), tantalum (Ta), tungsten ( W), metals such as titanium (Ti), or alloys containing these metal elements, conductive particles made of these metals, and conductive particles of alloys containing these metals. A layered structure of layers containing can also be used. Although the wiring formation method depends on the materials constituting these, physical vapor deposition method (PVD method); various chemical vapor deposition methods (CVD method) including MOCVD method; screen printing method and ink jet printing Various printing methods such as the offset printing method, offset printing method, gravure printing method, contact printing method, imprint method; lift-off method; shadow mask method; and plating methods such as electrolytic plating method, electroless plating method, or combinations thereof A combination of any of the above and a patterning technique can be given as necessary. In addition, as the PVD method, (a) various vacuum deposition methods such as electron beam heating method, resistance heating method, flash deposition, (b) plasma deposition method, (c) bipolar sputtering method, direct current sputtering method, direct current magnetron sputtering method Various sputtering methods such as high-frequency sputtering method, magnetron sputtering method, ion beam sputtering method, bias sputtering method, (d) DC (direct current) method, RF method, multi-cathode method, activation reaction method, electric field evaporation method, high-frequency method Various ion plating methods such as an ion plating method and a reactive ion plating method can be given.

  As a method for forming the conductive fixing member precursor layer, spin coating method; various printing methods such as screen printing method, inkjet printing method, offset printing method, gravure printing method, contact printing method, imprinting method; air doctor coater method, blade Coater method, rod coater method, knife coater method, squeeze coater method, reverse roll coater method, transfer roll coater method, gravure coater method, kiss coater method, cast coater method, spray coater method, slit orifice coater method, calendar coater method, immersion Various coating methods such as a coating method; a stamping method; and a coating method such as a spray method can be exemplified.

In order to obtain the conductive fixing member layer, the conductive fixing member precursor layer is heated.
(1) Not only the heat treatment for removing the solvent and solvent and various organic substances (for example, stabilizer) contained in the conductive fixing member precursor layer,
(2) Thermal decomposition or chemical reaction of a solution-type conductive material constituting a conductive fixing member precursor layer based on heating (3) Solution-type conductive material constituting a conductive fixing member precursor layer based on heating The concept of firing is included. Heating (including heat treatment, thermal decomposition, chemical reaction, and baking) may be performed in the air or in an inert gas atmosphere. What is necessary is just to set suitably the atmosphere of heating, the pressure at the time of heating, the time of heating, the temperature of heating, and temperature rising / falling pattern according to the electroconductive fixing member precursor layer to be used. After the conductive fixing member precursor layer is heated to obtain the conductive fixing member layer, the conductive fixing member layer may be annealed. When removing the conductive fixing member layer portion located below the element, etc., and removing the other conductive fixing member layer portions (exposed conductive fixing member layer portions not covered by the element, etc.) Specifically, the conductive fixing member layer may be etched using an etching solution or an etching gas suitable for the conductive fixing member layer that does not adversely affect the substrate or wiring, such as an element.

In the light emitting device assembly of the present invention or the light emitting device assembly of the present invention, specific examples of the connecting portion provided in the device include an electrode, a pad portion, a wiring portion, and a terminal portion. The number of connection portions per one element or the like fixed to the wiring is not limited to one, and may be two or more. When the number of connecting portions is two or more, it has been difficult in the prior art to set the pitch of the connecting portions to 30 μm or less. However, the method of the present invention or the present invention In the light-emitting element assembly, for example, bonding using bumps is possible even when the pitch of the connection portions is about 10 μm. Examples of the thickness of the conductive fixing member layer include 1 × 10 ⁻⁹ (m) to 1 × 10 ⁻⁵ (m), preferably 5 × 10 ⁻⁹ (m) to 1 × 10 ⁻⁷ (m). can do. Further, the volume resistance value of the conductive fixing member layer is 1 × 10 Ω · m (1 × 10 ³ Ω · cm) or less. For example, when the internal resistance value of the element is high, such as a light emitting element, 1 × 10 ^-2 Ω · m (1 Ω · cm) to 1 Ω · m (1 × 10 ² Ω · cm) can be exemplified. Even if the volume resistance value of the conductive fixing member layer is such a high value, there is no problem because the thickness of the conductive fixing member layer is thin and the internal resistance value of the element or the like is high.

  In the method of the present invention, the conductive fixing member precursor layer is made of a solution-type conductive material, but the solution-type conductive material basically does not contain a filler. The solution-type conductive material is made of, for example, a material in which a colloidal product obtained by hydrolyzing and polymerizing alkoxide or the like is dispersed in a solution. Alternatively, the solution-type conductive material is a liquid material composed of a solution in which a metal organic compound is dissolved in an organic solvent, and the solution is applied on a base (wiring, substrate, connection part) and dried. For example, it is made of a liquid material that can easily form an oxide by heating. Arrange the connection part of the element so that it contacts the conductive fixing member precursor layer, but the conductive fixing member precursor layer is sticky to the extent that the element does not move from the conductive fixing member precursor layer after the arrangement. It is preferable to have (tack).

  In a structure in which light emitted from the light emitting layer is emitted from the substrate, the wiring needs to have a shape, configuration, and structure that does not block the emitted light. Further, a black matrix layer may be formed on the portion of the substrate through which the emitted light does not pass. As a material constituting the black matrix layer, carbon, a metal thin film (for example, chromium, nickel, aluminum, molybdenum, etc., or an alloy thereof), a metal oxide (for example, chromium oxide), a metal nitride (for example, chromium nitride) ), A heat-resistant organic resin, a glass paste, and a glass paste containing conductive particles such as a black pigment and silver. The black matrix layer depends on the materials used, for example, vacuum deposition method, a combination of sputtering method and etching method, vacuum deposition method, sputtering method, combination of spin coating method and lift-off method, various printing methods, lithography technology, etc. Thus, it can be formed by an appropriately selected method. Further, a convex lens may be provided in the portion of the base body from which the emitted light is emitted. Examples of the material constituting the convex lens include acrylic resin, epoxy resin, and silicone rubber. As the convex lens forming method (arrangement method), reflow method, potting method, imprint method, photolithography method, etching method, The printing method can be mentioned.

  Examples of the method for producing the light emitting device assembly of the present invention or the light emitting device in the light emitting device assembly of the present invention include a light emitting diode (LED), a semiconductor laser, and an electroluminescence (EL) device. Examples of the element in the electrical connection method of the element to the wiring of the present invention include a light receiving element such as a photodiode, a CCD sensor, and a MOS sensor; and an electronic element such as an IC chip and an LSI chip. Alternatively, as an element, in addition to a semiconductor element [light emitting element, light receiving element, electron traveling element, etc.], piezoelectric element, pyroelectric element, optical element [second harmonic generation element using nonlinear optical crystal, etc.], dielectric Examples include elements [including ferroelectric elements], superconducting elements, and the like. Furthermore, as an element, the micro components or element used for various MEMS (Micro Electro Mechanical Systems), such as an optical encoder, can also be mentioned, for example. The size of the element or the like (for example, the chip size) is not particularly limited, but the element or the like is typically a minute one, and specifically, for example, 1 mm or less, or, for example, 0.3 mm or less, or, for example, The size is 0.1 mm or less, or 0.02 mm or less, for example.

  As an electronic device obtained by the method of the present invention or an electronic device to which the light emitting element assembly of the present invention can be applied, for example, a light emitting diode display device, a backlight using a light emitting diode, a light emitting diode illumination device, an EL A display device can be mentioned. Alternatively, the electronic device may be basically any device, including both portable devices and stationary devices. Specific examples include mobile phones, mobile devices, robots, Personal computers, in-vehicle devices, various home appliances, etc. As the red light emitting diode, the green light emitting diode, and the blue light emitting diode, for example, a nitride-based III-V compound semiconductor can be used. As the red light-emitting diode, for example, an AlGaInP-based compound semiconductor can be used. It can also be used.

  As a device manufacturing substrate for manufacturing a GaInN-based light emitting diode, at present, it is difficult to manufacture a substrate having a large diameter exceeding 2 inches nominal, and for manufacturing a device for manufacturing an AlGaInP-based light emitting diode. At present, it is difficult to manufacture a substrate having a large diameter exceeding a nominal size of 3 inches. Therefore, for example, a blue light emitting diode and a green light emitting diode are manufactured using a sapphire substrate having a nominal diameter of 2 inches as a device manufacturing substrate, and a red light emitting diode is manufactured using a GaAs substrate having a nominal diameter of 3 inches as a device manufacturing substrate. Is manufacturing. For example, when manufacturing a light-emitting diode display device, the number of blue light-emitting diodes, green light-emitting diodes, and red light-emitting diodes based on specifications may be mounted on the base.

By the way, as a method for manufacturing such a light emitting diode display device, a step transfer method is known from, for example, Japanese Patent Application Laid-Open Nos. 2004-273596 and 2004-281630. The manufacturing method of the light emitting element assembly of the present invention can be applied to this step transfer method. That is,
(A) A light emitting layer made of a laminated structure of compound semiconductor layers is formed on an element manufacturing substrate, and a second electrode is formed on the light emitting layer to obtain a laminated structure made of the second electrode and the light emitting layer.
(B) Next, after the laminated structure is bonded to the relay substrate so that the second electrode is in contact with the relay substrate, the element manufacturing substrate is removed from the light emitting layer, and the first electrode is formed on the exposed light emitting layer, Next, the light emitting layer is separated into light emitting elements by patterning.
(C) Thereafter, the desired light emitting element is transferred from the relay substrate to the substrate, and then the light emitting element assembly manufacturing method of the present invention is applied to fix the light emitting element on the wiring of the substrate.
(D) Next, an insulating layer is formed so as to cover the light emitting element, an opening is formed in the insulating layer above the first electrode or the second electrode of the light emitting diode, and connected to the first electrode or the second electrode. The second wiring is formed on the insulating layer. Note that the second electrode may correspond to the connection portion, and the first electrode may correspond to the connection portion.

  Then, the light emitting diode display device can be completed by connecting the wiring formed on the substrate and the second wiring to the driving circuit. In addition, the material which comprises the insulating film mentioned above can be mentioned as a material which comprises an insulating layer.

  Examples of the material constituting the substrate and the relay substrate include a glass plate, a metal plate, an alloy plate, a ceramic plate, and a plastic plate. As a method for bonding the laminated structure to the relay substrate, a metal bonding method, a semiconductor bonding method, and a metal / semiconductor bonding method can be used in addition to a method using an adhesive. Examples of a method for removing the element manufacturing substrate from the light emitting layer include a laser ablation method, a heating method, and an etching method. Examples of a method for separating the light emitting element into a plurality of light emitting devices include a wet etching method, a dry etching method, and laser irradiation. Examples thereof include a method, a dicing method, a lapping method, and a chemical mechanical polishing method (CMP method). As a method for transferring a desired element from the relay substrate to the substrate and a method for removing the element from the substrate, a laser ablation method can be cited, and the element is not supported with high strength to the left. In some cases, the element or the like can be removed from the substrate by the adhesiveness (tack) between the element or the like and the conductive fixing member precursor layer.

  In the method of the present invention, since the conductive fixing member precursor layer is made of a solution-type conductive material, the conductive fixing member layer obtained by heating the conductive fixing member precursor layer contains large particles. Not. Therefore, the element or the like and the wiring can be reliably electrically connected, and the problem that the element or the like is inclined on the wiring does not occur. Moreover, conduction can be obtained without applying pressure. Furthermore, there is no problem that a residue remains when an unnecessary portion of the conductive fixing member layer is removed. Further, in the method according to the first aspect of the present invention, the unnecessary portion of the conductive fixing member layer such as an element itself is used as an etching mask to remove an unnecessary portion of the conductive fixing member layer. In the method according to the embodiment, the conductive fixing member layer is formed only on the connection portion provided in the element or the like. Therefore, the complicated operation of patterning the conductive fixing member layer using the etching mask is performed. There is no need to do it. For example, an element of several tens of μm or less can be selectively fixed to the wiring over a wide range. Further, even in the light emitting device assembly according to the first aspect or the second aspect of the present invention, the conductive fixing member layer obtained by heating the conductive fixing member precursor layer has large particles. Not included. Therefore, the element or the like and the wiring can be reliably electrically connected, and the problem that the element or the like is inclined on the wiring does not occur. Moreover, conduction can be obtained without applying pressure. Furthermore, in the method of the present invention or the light emitting device assembly of the present invention, if the conductive fixing member layer is made of ITO or IZO, the conductive fixing member layer itself is an oxide, so that it is conductive even by heating. If the conductive fixing member layer contains carbon atoms, adhesion can be improved and high shear strength can be achieved. Further, in some cases, low temperature (for example, 400 Therefore, it is possible to reliably prevent adverse effects on the elements and the like. In the method according to the second aspect of the present invention or the light emitting element assembly according to the second aspect of the present invention, the conductive fixing member layer is formed only on the connection portion provided in the element or the like. Therefore, it is not necessary to form an extra conductive fixing member layer, and it is not necessary to remove the conductive fixing member layer after connection, so that the manufacturing cost can be reduced, and further, the substrate is formed with a wider pitch than the elements supported on the substrate. When arranging elements etc. on the wiring of the substrate (that is, adopting the step transfer method, which is a method of arranging elements etc. on the wiring of the substrate at a pitch thinned out by an integral multiple of the pitch of the elements supported on the substrate) ) The effect is extremely large.

  Hereinafter, the present invention will be described based on examples with reference to the drawings.

  Example 1 is a method of electrically connecting an element to a wiring according to the first aspect of the present invention, a method of manufacturing a light-emitting element assembly according to the first aspect of the present invention, and the first of the present invention. It relates to the light emitting element assembly which concerns on an aspect. Hereinafter, these methods are collectively referred to as the method of Example 1.

In Example 1, the element or the light emitting element is a light emitting diode (LED) having a circular planar shape (diameter 20 μm). Therefore, in the following description, the term “light emitting diode” may be used instead of the term “element”. Therefore, in the following description, when the term “light emitting diode” is used, the concept of “element” is included in principle. The conductive fixing member layer is made of ITO. The conductive fixing member precursor layer is made of a solution-type conductive material that does not contain fine particles having a particle size exceeding 1 × 10 ⁻⁷ m. More specifically, the solution-type conductive material does not contain a filler. The solution-type conductive material is composed of a material in which a colloidal product obtained by hydrolyzing and polymerizing indium alkoxide and tin alkoxide is dispersed in a solution. In the first embodiment, the wiring is made of gold (Au), and the connection portion (second electrode) of the light emitting diode is made of a metal multilayer film having an Ag / Pt / Au structure. In the connection part (second electrode) of the light emitting diode composed of a metal multilayer film having an Ag / Pt / Au structure, the Ag film is in contact with the light emitting layer, and the Au film is in contact with the conductive fixing member layer. Yes. The wiring is composed of a plurality of wirings extending in a strip shape. The substrate on which the wiring is formed is made of a glass substrate on the surface of which an insulating film made of SiO ₂ is formed. The electronic device obtained by the method of Example 1 is a light emitting diode display device. The above matters are the same in Examples 2 to 5 described later.

  FIG. 1 shows a schematic partial cross-sectional view of a light-emitting diode assembly obtained by the method of Example 1. FIG. In this light-emitting diode assembly, the connection portion (p-side electrode or second electrode) 25 of the light-emitting diode 10 and the wiring 41 formed on the base body 40 are fixed by the conductive fixing member layer 43, and the light-emitting diode assembly emits light. The conductive fixing member layer 43 exists only below the diode 10, and the conductive fixing member layer 43 is made of ITO. Specifically, the light-emitting diode assembly includes a light-emitting diode 10, a base body 40, a wiring 41 formed on the base body 40, a conductive fixing member layer 43, a second wiring 51, and an insulating layer 52. It is composed of The light emitting diode 10 includes a connection portion (p-side electrode or second electrode) 25, a light emitting layer 24, and a first electrode (n-side electrode) 27. The light emitting layer 24 has a stacked structure of a first compound semiconductor layer 21 having an n-type conductivity, an active layer 23, and a second compound semiconductor layer 22 having a p-type conductivity from the n-side electrode side. The wiring 41 and the connecting portion (p-side electrode or second electrode) 25 are fixed (for example, bonded) by the conductive fixing member layer 43. In addition, the conductive fixing member layer 43 exists only below the light emitting diode 10. That is, the portion of the conductive fixing member layer 43 located below the light emitting diode 10 is left, but the other portions of the conductive fixing member layer 43 are removed. The side surface and the top surface (n-side electrode 27) of the light emitting diode 10 are covered with an insulating layer 52, and an opening 53 is provided in the insulating layer 52 above the n-side electrode 27. The second wiring 51 is formed, and the second wiring extending portion 51 </ b> A extending from the n-side electrode 27 to the second wiring 51 through the opening 53 is formed. The wiring 41 extends in a direction parallel to the drawing sheet, and the second wiring 51 extends in a direction perpendicular to the drawing sheet. The light emitted from the light emitting layer 24 is emitted from the substrate 40. The wiring 41 has a shape that does not block the emitted light. A black matrix layer may be formed on the portion of the substrate 40 through which the emitted light does not pass. Furthermore, the light extraction function may be imparted (for example, the light extraction mirror is also used) by sufficiently widening the extending portion 51A of the second wiring. The light emitting diode 10 has a truncated cone shape as a whole. Specifically, the compound semiconductor constituting the first compound semiconductor layer 21, the active layer 23, and the second compound semiconductor layer 22 is, for example, a GaInN-based compound semiconductor or an AlGaInP-based compound semiconductor. The same applies to Examples 2 to 5 described later.

  When the light-emitting diode 10 is, for example, a GaN-based light-emitting diode, specific examples of dimensions, materials, etc. of each part are as follows. That is, the first compound semiconductor layer 21 is composed of an n-type GaN layer having a thickness of 2.6 μm, and the active layer 23 is 0.2 μm in thickness, for example, and is a multiple quantum composed of an InGaN well layer and a GaN barrier layer. It has a well (MQW) structure. The second compound semiconductor layer 22 is composed of a p-type GaN layer having a thickness of 0.2 μm. The In composition of the InGaN well layer constituting the active layer 23 is, for example, 0.17 when the GaN-based light-emitting diode is a blue light-emitting diode, and for example, 0.25 when the GaN-based light-emitting diode is a green light-emitting diode. The maximum diameter of the light emitting diode 10, that is, the diameter of the lower surface of the second compound semiconductor layer 22 is 20 μm, and the total thickness of the light emitting diode 10 is 5 μm. As described above, the connection portion (p-side electrode) 25 is made of, for example, a metal multilayer film having an Ag / Pt / Au structure. The n-side electrode 27 is made of a metal laminated film having a Ti / Pt / Au structure, for example. The same applies to Examples 2 to 5 described later.

In Example 1, the volume resistivity of the conductive fixing member layer 43 is 3 × 10 ⁻³ Ω · m (0.3 Ω · cm), and the thickness is about 30 nm.

  Hereinafter, FIG. 1, FIG. 2 which is a process conceptual diagram, FIGS. 3A and 3B and FIGS. 4A to 4C which are schematic partial sectional views of a laminated structure and the like, FIG. Referring to (A) and (B) of FIG. 5, (A) and (B) of FIG. 6, (A) and (B) of FIG. 7, and (A) and (B) of FIG. The method of Example 1 will be described.

[Step-100]
First, a light emitting layer 24 having a laminated structure of compound semiconductor layers is formed on the element manufacturing substrate 20 by a known method, and a connection portion (corresponding to a p-side electrode) 25 is formed on the light emitting layer 24. Specifically, for example, a first compound semiconductor layer 21, an active layer 23, and a p-type having an n-type conductivity are formed on an element manufacturing substrate 20 made of a sapphire substrate having a nominal diameter of 2 inches based on the MOCVD method. The second compound semiconductor layer 22 having the following conductivity type is sequentially formed, and a connection portion (p-side electrode) made of a metal multilayer film having an Ag / Pt / Au structure is further formed on the second compound semiconductor layer 22 by a vacuum deposition method. Alternatively, the second electrode) 25 is formed. Thus, a laminated structure 26 including the light emitting layer 24 composed of the first compound semiconductor layer 21, the active layer 23, and the second compound semiconductor layer 22, and the connection portion (p-side electrode) 25 can be obtained (FIG. 2 (A) and FIG. 3 (A)). Depending on the drawing, the light emitting layer 24 and the laminated structure 26 may be represented by one layer.

[Step-110]
Next, the laminated structure 26 is bonded to the relay substrate 30 so that the connection portion (p-side electrode) 25 is in contact with the relay substrate 30, and then the element manufacturing substrate 20 is removed from the light emitting layer 24. Then, the n-side electrode 27 is formed on the exposed light emitting layer 24, and then the light emitting layer 24 is patterned to be separated into the light emitting diodes 10. Specifically, first, the connection portion (p-side electrode) 25 is bonded to the relay substrate 30 (see FIG. 2B and FIG. 3B). More specifically, a relay substrate 30 made of a glass substrate having a surface on which an adhesive layer 31 made of an uncured adhesive is formed is prepared. Then, the connection portion (p-side electrode) 25 and the adhesive layer 31 in the laminated structure 26 are bonded together, and the adhesive layer 31 is cured. Thereafter, the element manufacturing substrate 20 is removed from the light emitting layer 24 (see FIG. 2C and FIG. 4A). Specifically, the interface between the light emitting layer 24 (more specifically, the first compound semiconductor layer 21) and the device manufacturing substrate 20 is irradiated with an excimer laser through the device manufacturing substrate 20, thereby providing a laser. As a result of ablation, the element manufacturing substrate 20 can be peeled off from the light emitting layer 24.

  Next, a first electrode (n-side electrode) 27 is formed on the first compound semiconductor layer 21 constituting the light-emitting layer 24 bonded to the relay substrate 30 (see FIG. 2D). Thereafter, the plurality of light emitting diodes 10 can be obtained by etching the first electrode (n-side electrode) 27, the light emitting layer 24, and the connection portion (p side electrode) 25 based on the photolithography technique and the etching technique ( (See FIG. 4B). A schematic partial sectional view in which the light emitting diode 10 is enlarged is shown in FIG. The light emitting diodes 10 are left on the relay substrate 30 in an array (two-dimensional matrix). The planar shape of the light emitting diode 10 was a circle having a diameter of 20 μm.

[Step-120]
Thereafter, the desired light emitting diode 10 is transferred from the relay substrate 30 to a substrate (hereinafter referred to as a support substrate 32 for convenience). That is, each light emitting diode 10 bonded to the relay substrate 30 is attached to the support substrate 32. Specifically, first, a light-adhesive layer 33 formed on the surface of a support substrate 32 made of a glass plate is formed on the light-emitting diode 10 on the relay substrate 30 where the light-emitting diodes 10 are left in an array (two-dimensional matrix). (See (E) in FIG. 2, (A) in FIG. 5 and (B) in FIG. 5)). The slightly adhesive layer 33 is made of, for example, silicone rubber. The support substrate 32 is held by a positioning device (not shown). The positional relationship between the support substrate 32 and the relay substrate 30 can be adjusted by the operation of the positioning device. Next, for example, excimer laser is irradiated to the light emitting diode 10 to be mounted from the back side of the relay substrate 30 (see FIG. 6A). As a result, laser ablation occurs, and the light emitting diode 10 irradiated with the excimer laser is peeled off from the relay substrate 30. Thereafter, when the contact between the support substrate 32 and the light emitting diode 10 is released, the light emitting diode 10 peeled off from the relay substrate 30 is attached to the slightly adhesive layer 33 ((F) of FIG. 2 and (B) of FIG. 6). )reference).

[Step-130]
Next, the method according to the first aspect of the present invention is performed. That is, first, the conductive fixing member precursor layer 42 is formed on at least the wiring 41 provided on the base body 40. Specifically, the conductive fixing member precursor layer 42 is formed on the substrate 40 including the wiring 41. More specifically, the substrate 40 is obtained by forming the wiring 41 on an insulating film (not shown) made of SiO ₂ formed on the surface of the glass substrate by a known method. Then, the conductive fixing member precursor layer 42 is formed on the entire surface based on the spin coating method (see FIG. 7A). The conductive fixing member precursor layer 42 may or may not be subjected to a pre-bake treatment such as 60 ° C. for 1 minute.

  Then, the light emitting diode 10 provided with the connection portion (p-side electrode) 25 is disposed on the wiring 41 so that the connection portion (p-side electrode) 25 is in contact with the conductive fixing member precursor layer 42 (see FIG. 2). (See (G) and (H) and FIGS. 7A and 7B). Specifically, in a state where the connection portion (p-side electrode or second electrode) 25 provided in the light emitting diode 10 supported on the support substrate 32 is in contact with the conductive fixing member precursor layer 42, the light emitting diode. 10 is removed from the support substrate 32. More specifically, the light emitting diode 10 in the state attached to the slightly adhesive layer 33 obtained in [Step-120] is pressed against the conductive fixing member precursor layer 42. Since the light emitting diode 10 is only weakly adhered to the slightly adhesive layer 33 and the conductive fixing member precursor layer 42 has adhesiveness (tack), the conductive fixing member precursor layer 42. The light emitting diode 10 pressed against is detached from the slightly adhesive layer 33. When the light emitting diode 10 is moved in a direction away from the base body 40 in a state where the light emitting diode 10 is in contact with (pressed on) the conductive fixing member precursor layer 42, the light emitting diode 10 is placed on the conductive fixing member precursor layer 42. Left behind. Thus, a desired number of light emitting diodes 10 can be temporarily fixed on the conductive fixing member precursor layer 42. The conductive fixing member precursor layer 42 has adhesiveness (tack) to the extent that the light emitting diode 10 does not move from the conductive fixing member precursor layer 42.

  The above [Step-120] and [Step-130] are repeated a desired number of times, and a desired number of light-emitting diodes are temporarily fixed on the wiring 41. Such a method using the support substrate 32 is referred to as a step transfer method for convenience. Then, by repeating such a step transfer method a desired number of times, a desired number of light emitting diodes 10 are arranged on the conductive fixing member precursor layer 42 in a two-dimensional matrix. Specifically, assuming that 1920 × 1080 × (the number of three types of light emitting diodes) are mounted, for example, 160 × 120 light emitting diodes 10 are conductive in one step transfer. It is assumed that the two-dimensional matrix is arranged on the conductive fixing member precursor layer 42. Then, in this case, by repeating the step transfer method of (1920 × 1080) / (160 × 120) = 108 times, 1920 × 1080 light emitting diodes 10 are formed on the conductive fixing member precursor layer 42. Can be arranged. Then, by repeating the above [Step-100] to [Step-130] a total of three times, a predetermined number of red light emitting diodes, green light emitting diodes, and blue light emitting diodes are formed on the substrate 40 at predetermined intervals and pitches. Can be implemented. The light emitting diode 10 left on the relay substrate 30 may be used for mounting the light emitting diode 10 on the next substrate 40.

[Step-140]
Thereafter, the conductive fixing member precursor layer 42 is heated to obtain the conductive fixing member layer 43, whereby the connection portion (p-side electrode) 25 of the light emitting diode 10 is connected to the wiring 41 through the conductive fixing member layer 43. Fix (see FIG. 8A). Specifically, for example, the temperature is raised to 350 ° C. in an oxygen gas atmosphere or an air atmosphere, heated for 30 minutes at 350 ° C. (baking treatment), and then heated to 450 ° C. as a nitrogen gas atmosphere. Then, heating (annealing) at 450 ° C. for 30 minutes may be performed. However, heating (annealing treatment) in a nitrogen gas atmosphere can be omitted. The conductive fixing member layer 43 made of ITO obtained under these heating conditions is in an amorphous state.

[Step-150]
Next, the conductive fixing member layer 43 located below the light emitting diode 10 is left, and the other conductive fixing member layer 43 is removed (see FIG. 8B). Specifically, the light emitting diode 10 functions as a kind of etching mask by immersing the whole in an etching solution composed of an aqueous solution of ferric chloride or an organic acid, and the exposed conductive material not covered by the light emitting diode 10 is exposed. The portion of the fixing member layer 43 can be removed. Thus, the light emitting diode 10 can be fixed in a state of being electrically connected to the wiring 41.

[Step-160]
Thereafter, an insulating layer 52 is formed so as to cover the light emitting diode 10, an opening 53 is formed in the insulating layer 52 above the first electrode (n-side electrode) 27 of the light-emitting diode, and the first electrode (n-side electrode) ) The second wiring 51 connected to 27 and the extended portion 51A of the second wiring are formed on the insulating layer 52 (see FIG. 1). Then, the light emitting diode display device can be completed by connecting the wiring 41 and the second wiring 51 to the driving circuit.

  In the first embodiment, the connection portion provided in the light emitting diode can be reliably and relatively easily connected to the wiring with high reliability. In addition, when a small light emitting diode is mounted on the substrate, the light emitting diode does not shift to an undesired position or tilts, and can be mounted easily and reliably with high positional accuracy. It becomes.

  The second embodiment is a modification of the first embodiment. In Example 2, the metal constituting the wiring 41 and the metal constituting the connecting portion (p-side electrode or second electrode) 25 of the light emitting diode 10 are silver (Ag). In Example 2, after performing [Step-150], alloying heat treatment is performed, and silver (Ag), which is a metal constituting the wiring 41, and a metal, which constitutes the conductive fixing member layer 43, are processed. (Indium and tin) and silver (Ag) which is a metal constituting the connection part (p-side electrode) 25 of the light emitting diode 10 are alloyed. As conditions for the alloying heat treatment, the atmosphere was a nitrogen gas atmosphere, the temperature was 350 ° C., and the treatment time was 30 minutes. Except for this point, the method of the second embodiment can be the same as the method of the first embodiment, and a detailed description thereof will be omitted.

  The third embodiment is also a modification of the first embodiment. In the third embodiment, the metal layer 60 for alloying is formed in the region of the projected image of the light emitting diode 10 that is vertically projected onto the substrate 40. Specifically, a schematic partial cross-sectional view in the same process as [Process-140] in Example 1 is shown in FIG. 9A, and a metal layer 60 made of Ti is formed on the wiring 41. Is formed. Note that, as shown in FIG. 9B, a metal layer 60 made of Ti may be formed between the wiring 41 and the substrate 40.

  In Example 3, in the same step as [Step-140], the temperature was raised to 350 ° C. in an air atmosphere, and heating (firing treatment) was performed at 350 ° C. for 60 minutes. In addition, alloying heat processing was also performed simultaneously by this heating. That is, gold (Au) that is a metal constituting the wiring 41, metal (indium and tin) that constitutes the conductive fixing member layer 43, and metal that constitutes the connection portion (p-side electrode) 25 of the light emitting diode 10. A metal layer 60 made of some gold (Au) and titanium (Ti) was alloyed. Thus, as shown in FIG. 9C, the alloy layer 61 is formed by the conductive fixing member precursor layer 42, the metal layer 60, and the wiring 41 below the light emitting diode 10, or the light emission. An alloy layer 61 is formed by the conductive fixing member precursor layer 42, the wiring 41, and the metal layer 60 below the diode 10. Except for the above points, the method of the third embodiment can be the same as the method of the first embodiment, and a detailed description thereof will be omitted.

  In Example 3, in the same step as [Step-150] of Example 1, the portion of the conductive fixing member layer 43 located below the light emitting diode 10 is left, and the other conductive fixing member layer 43 is left. The portion of the conductive fixing member layer 43 located below the light emitting diode 10 is alloyed, and the other portions of the conductive fixing member layer 43 are not alloyed. Therefore, there is a large difference between the etching rate of the portion of the conductive fixing member layer 43 that is alloyed below the light emitting diode 10 and the etching rate of the portion of the other conductive fixing member layer 43 that is not alloyed. As a result, the other conductive fixing member layer 43 that is not alloyed can be reliably removed by etching. Moreover, it is not necessary to form an etching mask based on a photolithography technique or the like.

  Example 4 relates to a light-emitting element assembly according to the second aspect of the present invention. In the light-emitting element assembly of Example 4, the connection portion (p-side electrode or second electrode) 25 of the light-emitting diode 10 and the wiring 41 formed on the base 40 are fixed by the conductive fixing member layer 43. The conductive fixing member layer 43 includes at least metal atoms, carbon (C) atoms, and oxygen (O) atoms. More specifically, in Example 1, indium (In) as metal atoms and It is composed of tin (Sn) and carbon (C) atoms and oxygen (O) atoms. Here, the proportion of carbon (C) atoms is about 20% by weight.

In Example 4, in the same step as [Step-140] of Example 1, for example, the temperature was raised to 320 ° C. in an air atmosphere, and heating was performed at 320 ° C. for 30 minutes. In such a relatively low temperature heating state, the solvent and various organic substances (for example, stabilizer) contained in the conductive fixing member precursor layer 42 are removed, but the conductive fixing member precursor layer 42 has Rather than the conductive fixing member layer 43 made of ITO formed by thermal decomposition or chemical reaction, indium (In) atoms and tin (Sn) atoms as metal atoms, and carbon (C) atoms, In addition, it is considered that the conductive fixing member layer 43 is composed of oxygen (O) atoms bonded to these atoms. The volume resistivity of the conductive fixing member layer 43 at this time was 3 × 10 ⁻³ Ω · m (0.3 Ω · cm), and the thickness was about 30 nm.

  Except for the above points, the method of the fourth embodiment can be the same as the method of the first embodiment, and a detailed description thereof will be omitted.

  Example 5 relates to a method for electrically connecting an element to a wiring according to a second aspect of the present invention, and a method for manufacturing a light emitting element assembly according to the second aspect of the present invention. Hereinafter, these methods are collectively referred to as the method of Example 5. Here, a schematic partial cross-sectional view of the light-emitting diode assembly obtained by the method of Example 5 is the same as that shown in FIG. That is, in this light emitting diode assembly, the connection portion (p-side electrode or second electrode) 25 of the light emitting diode 10 and the wiring 41 formed on the base body 40 are fixed by the conductive fixing member layer 43. The conductive fixing member layer 43 is made of ITO. The conductive fixing member layer 43 exists only below the light emitting diode 10.

  Hereinafter, FIG. 1, FIG. 2 which is a conceptual diagram of the process, FIGS. 3A and 3B which are schematic partial sectional views of a laminated structure and the like, and FIGS. 5, (A) and (B), FIG. 6 (A) and (B), FIG. 10 (A) and (B), and FIG. 11, the method of Example 5 is demonstrated. To do.

[Step-500]
First, in the same manner as in [Step-100] of Example 1, the light emitting layer 24 having a laminated structure of compound semiconductor layers is formed on the element manufacturing substrate 20 by a well-known method, and the connection portion ( 25 (corresponding to the p-side electrode) is formed (see FIG. 2A and FIG. 3A).

[Step-510]
Next, in the same manner as in [Step-110] of Example 1, the laminated structure 26 is bonded to the relay substrate 30 so that the connection portion (p-side electrode) 25 is in contact with the relay substrate 30, and then the element manufacturing substrate 20 is bonded. Is removed from the light emitting layer 24. Then, the n-side electrode 27 is formed on the exposed light emitting layer 24, and then the light emitting layer 24 is patterned to be separated into the light emitting diodes 10 ((B) to (D) in FIG. 2 and (B) in FIG. 3). FIG. 4 (A) to (C)).

[Step-520]
Thereafter, in the same manner as in [Step-120] in Example 1, the desired light emitting diode 10 is transferred from the relay substrate 30 to the support substrate 32 ((E) to (F) in FIG. 2, (A) in FIG. 5). , (B), see FIGS. 6A and 6B).

[Step-530]
Next, the method according to the second aspect of the present invention is performed. That is, the conductive fixing member precursor layer 42 is formed on the connection portion (p-side electrode or second electrode) 25 provided in the light emitting diode 10 based on an appropriate printing method (for example, ink jet printing method) (see FIG. 10 (A)). The conductive fixing member precursor layer 42 may or may not be subjected to a pre-bake treatment such as 60 ° C. for 1 minute.

[Step-540]
Then, the light emitting diode 10 is disposed on the wiring 41 so that the conductive fixing member precursor layer 42 is in contact with the wiring 41 provided on the base body 40 ((G) to (H) in FIG. 2 and FIG. 10). (See (B)). Specifically, the conductive fixing member precursor layer 42 formed on the connection portion (p-side electrode or second electrode) 25 provided in the light emitting diode 10 supported on the support substrate 32 is brought into contact with the wiring 41. In this state, the light emitting diode 10 is removed from the support substrate 32. More specifically, the conductive fixing member precursor layer 42 in the light emitting diode 10 in the state of being attached to the slightly adhesive layer 33 obtained in [Step-530] is pressed against the wiring 41. Since the light emitting diode 10 is only weakly adhered to the slightly adhesive layer 33 and the conductive fixing member precursor layer 42 has adhesiveness (tack), the conductive fixing member precursor layer 42. The LED 10 pressed against the wiring 41 is detached from the slightly adhesive layer 33. When the support substrate 32 is moved in a direction away from the base body 40 in a state where the conductive fixing member precursor layer 42 of the light emitting diode 10 is in contact (pressed) with the wiring 41, the light emitting diode 10 becomes a conductive fixing member precursor layer. 42 is left on the wiring 41 via 42. Thus, a desired number of light emitting diodes 10 can be temporarily fixed onto the wiring 41 via the conductive fixing member precursor layer 42. The conductive fixing member precursor layer 42 has adhesiveness (tack) to such an extent that the conductive fixing member precursor layer 42 does not move from the wiring 41.

  The above-mentioned [Step-530] and [Step-540] are repeated a desired number of times, and a desired number of light-emitting diodes are temporarily fixed on the wiring 41. Then, by repeating the step transfer method a desired number of times, a desired number of light emitting diodes 10 are arranged in a two-dimensional matrix form on the wiring 41 via the conductive fixing member precursor layer 42. Furthermore, by repeating the above [Step-500] to [Step-540] a total of three times, a predetermined number of red light emitting diodes, green light emitting diodes, and blue light emitting diodes are arranged at a predetermined interval and pitch. Can be implemented. The light emitting diode 10 left on the relay substrate 30 may be used for mounting the light emitting diode 10 on the next substrate 40.

[Step-550]
Thereafter, the conductive fixing member precursor layer 42 is heated to obtain the conductive fixing member layer 43, whereby the connection portion (p-side electrode) 25 of the light emitting diode 10 is connected to the wiring 41 through the conductive fixing member layer 43. Fix (see FIG. 11). Specifically, for example, the temperature is raised to 350 ° C. in an oxygen gas atmosphere or an air atmosphere, heated for 30 minutes at 350 ° C. (baking treatment), and then heated to 450 ° C. as a nitrogen gas atmosphere. Then, heating (annealing) at 450 ° C. for 30 minutes may be performed. However, heating (annealing treatment) in a nitrogen gas atmosphere can be omitted. The conductive fixing member layer 43 made of ITO obtained under these heating conditions is in an amorphous state.

[Step-560]
Thereafter, an insulating layer 52 is formed so as to cover the light emitting diode 10, an opening 53 is formed in the insulating layer 52 above the first electrode (n-side electrode) 27 of the light-emitting diode, and the first electrode (n-side electrode) ) The second wiring 51 connected to 27 and the extended portion 51A of the second wiring are formed on the insulating layer 52 (see FIG. 1). Then, the light emitting diode display device can be completed by connecting the wiring 41 and the second wiring 51 to the driving circuit.

  Even in the fifth embodiment, the connection portion provided in the light emitting diode can be reliably and relatively easily connected to the wiring with high reliability. In addition, when a small light emitting diode is mounted on the substrate, the light emitting diode does not shift to an undesired position or tilts, and can be mounted easily and reliably with high positional accuracy. It becomes.

  The alloying described in Example 2 can be applied to Example 5. Further, the alloying described in the third embodiment can be applied to the fifth embodiment. FIG. 12A shows a schematic partial cross-sectional view in the same process as [Process-540] of Example 5 in this case. A metal layer 60 made of Ti is formed on the wiring 41. ing. As shown in FIG. 12B, a metal layer 60 made of Ti may be formed between the wiring 41 and the substrate 40. Then, after performing [Step-540], an alloying heat treatment is performed, gold (Au) which is a metal constituting the wiring 41, metal (indium and tin) which constitutes the conductive fixing member layer 43, and light emission Gold (Au), which is a metal constituting the connecting portion (p-side electrode) 25 of the diode 10, and a metal layer 60 made of titanium (Ti) are alloyed. Thus, as shown in FIG. 12C, the alloy layer 61 is formed by the conductive fixing member precursor layer 42, the metal layer 60, and the wiring 41 below the light emitting diode 10, or the light emission. An alloy layer 61 is formed by the conductive fixing member precursor layer 42, the wiring 41, and the metal layer 60 below the diode 10. Alternatively, the light-emitting element assembly according to the second aspect of the present invention described in Example 4 can be applied to Example 5.

  As mentioned above, although this invention was demonstrated based on the preferable Example, this invention is not limited to these Examples, Various deformation | transformation based on the technical idea of this invention is possible. For example, the numerical values, materials, configurations, structures, shapes, various substrates, raw materials, processes, etc. given in the examples are merely examples, and different values, materials, configurations, structures, shapes, substrates, etc., as necessary. , Raw materials, processes, etc. can be used.

  In Example 1 to Example 4, the conductive fixing member precursor layer 42 was formed on the entire surface (on the substrate 40 including the wiring 41) based on the spin coating method. The conductive fixing member precursor layer 42 may be formed only on a desired region of the wiring 41 based on various printing methods such as a method, an offset printing method, a gravure printing method, a contact printing method, and an imprinting method. According to such a method, [Step-150] of Example 1 can be omitted. In the embodiment, the number of connection portions fixed to the wiring is one. However, the number of connection portions is not limited to this, and may be two or more depending on the element or the like.

1 is a schematic partial cross-sectional view of a light-emitting diode assembly including an element (light-emitting element) obtained by a method for electrically connecting elements to wiring or a method for manufacturing a light-emitting element assembly in Example 1. FIG. . FIG. 2 is a process conceptual diagram for explaining each process of the method for electrically connecting the element to the wiring or the method for manufacturing the light emitting element assembly according to the first embodiment. 3A and 3B are schematic partial cross-sectional views of a light emitting layer and the like for explaining a method for electrically connecting elements to the wiring of Example 1 or a method for manufacturing a light emitting element assembly. is there. 4 (A) and 4 (B) show a light emitting layer and the like for explaining a method of electrically connecting elements to the wiring of Example 1 or a method of manufacturing a light emitting element assembly, following FIG. 3 (B). FIG. 4C is a schematic partial cross-sectional view in which the light-emitting diode obtained in [Step-110] is enlarged. 5 (A) and 5 (B) show a light emitting layer and the like for explaining a method of electrically connecting elements to the wiring of Example 1 or a method of manufacturing a light emitting element assembly, following FIG. 4 (B). It is a typical partial sectional view of. 6 (A) and 6 (B) show a light emitting layer and the like for explaining a method of electrically connecting elements to the wiring of Example 1 or a method of manufacturing a light emitting element assembly, following FIG. 5 (B). It is a typical partial sectional view of. FIGS. 7A and 7B show a light emitting layer and the like for explaining a method of electrically connecting elements to the wiring of Example 1 or a method of manufacturing a light emitting element assembly, following FIG. 6B. It is a typical partial sectional view of. 8A and 8B are light emitting layers for explaining a method for electrically connecting elements to the wiring of Example 1 or a method for manufacturing a light emitting element assembly, etc., following FIG. 7B. It is a typical partial sectional view of. 9A and 9B are schematic partial cross-sectional views in the same process as [Process-140] in Example 1, in Example 3, and FIG. 9C is an alloy. It is typical partial sectional drawing of a light emitting diode etc. after performing the heat processing for conversion. 10 (A) and 10 (B) show the light emitting layer and the like for explaining the electrical connection method of the element to the wiring or the manufacturing method of the light emitting element assembly in Example 5 following FIG. 6 (B). It is a typical partial sectional view of. FIG. 11 is a schematic partial cross-sectional view of a light emitting layer and the like for explaining a method for electrically connecting elements to the wiring of Example 5 or a method for manufacturing a light emitting element assembly, following FIG. It is. FIGS. 12A and 12B are schematic partial cross-sectional views in the same process as [Process-540] of Example 5, in a modification similar to Example 3 of Example 5. FIG. 12C is a schematic partial cross-sectional view of a light emitting diode and the like after heat treatment for alloying. FIGS. 13A and 13B are schematic diagrams for explaining problems in the prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Light emitting diode, 20 ... Element manufacturing substrate, 21 ... 1st compound semiconductor layer, 22 ... 2nd compound semiconductor layer, 23 ... Active layer, 24 ... Light emitting layer, 25 ... Connection part (p-side electrode or second electrode), 26 ... Laminated structure, 27 ... n-side electrode, 30 ... relay substrate, 31 ... adhesive layer, 32 ... Substrate (supporting substrate), 33 ... slightly adhesive layer, 40 ... base, 41 ... wiring, 42 ... conductive fixing member precursor layer, 43 ... conductive fixing member layer, 51. ..Second wiring, 51A ... extended portion of second wiring, 52 ... insulating layer, 53 ... opening, 60 ... metal layer, 61 ... alloy layer

Claims (28)

(A) forming a conductive fixing member precursor layer on at least the wiring provided on the substrate;
(B) After disposing the element provided with the connection portion on the wiring so that the connection portion is in contact with the conductive fixing member precursor layer, the conductive fixing member precursor layer is heated to form the conductive fixing member layer. By obtaining, fixing the connection portion of the element to the wiring through the conductive fixing member layer,
Consisting of processes,
The conductive fixing member precursor layer is made of a solution-type conductive material, and the element is electrically connected to the wiring. In the step (A), a conductive fixing member precursor layer is formed on the substrate including the wiring,
2. The method according to claim 1, further comprising: after the step (B), leaving a portion of the conductive fixing member layer positioned below the element and removing other conductive fixing member layer portions. Electrical connection method.   In the step (B), the element is disposed on the wiring by removing the element from the substrate in a state where the connection portion provided in the element supported on the substrate is in contact with the conductive fixing member precursor layer. The electrical connection method according to claim 1. 2. The electrical connection method according to claim 1, wherein the conductive fixing member precursor layer does not contain fine particles having a particle size exceeding 1 × 10 ⁻⁷ m.   The electrical connection method according to claim 1, wherein the conductive fixing member layer is made of ITO or IZO.   In the step (B) or after the step (B), the metal forming the wiring and the metal forming the conductive fixing member layer are alloyed or the element connecting portion is formed by heat treatment. Alloying of metal and metal constituting the conductive fixing member layer, or alloying of metal constituting the wiring and metal constituting the conductive fixing member layer, and metal and conductive fixing of the element connecting portion 2. The electrical connection method according to claim 1, wherein alloying with a metal constituting the member layer is achieved.   7. The electrical connection method according to claim 6, wherein a metal layer for alloying is formed in a region of a projected image of the element vertically projected onto the substrate. (A) forming a conductive fixing member precursor layer on the connection portion provided in the element;
(B) By arranging the element on the wiring so that the conductive fixing member precursor layer is in contact with the wiring provided on the substrate, the conductive fixing member precursor layer is heated to obtain the conductive fixing member layer. Fixing the connection portion of the element to the wiring through the conductive fixing member layer,
Consisting of processes,
The conductive fixing member precursor layer is made of a solution-type conductive material, and the element is electrically connected to the wiring.   In the step (B), the element is removed from the substrate in a state where the conductive fixing member precursor layer formed on the connection portion provided on the element supported on the substrate is in contact with the wiring provided on the base. The electrical connection method according to claim 8, wherein the element is arranged on the wiring by removing the element. The electrical connection method according to claim 8, wherein the conductive fixing member precursor layer does not contain fine particles having a particle size exceeding 1 × 10 ⁻⁷ m.   The electrical connection method according to claim 8, wherein the conductive fixing member layer is made of ITO or IZO.   In the step (B) or after the step (B), the metal forming the wiring and the metal forming the conductive fixing member layer are alloyed or the element connecting portion is formed by heat treatment. Alloying of metal and metal constituting the conductive fixing member layer, or alloying of metal constituting the wiring and metal constituting the conductive fixing member layer, and metal and conductive fixing of the element connecting portion 9. The electrical connection method according to claim 8, wherein alloying with a metal constituting the member layer is achieved.   13. The electrical connection method according to claim 12, wherein a metal layer for alloying is formed in a region of a projected image of the element vertically projected onto the substrate. (A) forming a conductive fixing member precursor layer on at least the wiring provided on the substrate;
(B) A light emitting element having a connection portion is arranged on the wiring so that the connection portion is in contact with the conductive fixing member precursor layer, and then the conductive fixing member precursor layer is heated to form a conductive fixing member layer. By fixing the connection part of the light emitting element to the wiring through the conductive fixing member layer,
Consisting of processes,
The method of manufacturing a light-emitting element assembly, wherein the conductive fixing member precursor layer is made of a solution-type conductive material. In the step (A), a conductive fixing member precursor layer is formed on the substrate including the wiring,
15. The method according to claim 14, further comprising a step of leaving a portion of the conductive fixing member layer located below the light emitting element and removing a portion of the other conductive fixing member layer after the step (B). Manufacturing method of the light emitting device assembly.   In the step (B), the light emitting element is removed from the substrate by removing the light emitting element from the substrate in a state where the connection portion provided in the light emitting element supported on the substrate is in contact with the conductive fixing member precursor layer. The method of manufacturing a light emitting device assembly according to claim 14, wherein: The method of manufacturing a light-emitting element assembly according to claim 14, wherein the conductive fixing member precursor layer does not contain fine particles having a particle size exceeding 1 × 10 ^-7 m.   The method of manufacturing a light emitting device assembly according to claim 14, wherein the conductive fixing member layer is made of ITO or IZO.   During the step (B) or after the step (B), by heat treatment, the metal constituting the wiring and the metal constituting the conductive fixing member layer are alloyed, or the connection portion of the light emitting element is constituted. Alloying between the metal forming the conductive fixing member layer and the metal forming the wiring, or alloying between the metal forming the wiring and the metal forming the conductive fixing member layer, and the metal forming the connection portion of the light emitting element and the conductive The method of manufacturing a light emitting element assembly according to claim 14, wherein alloying with a metal constituting the conductive fixing member layer is achieved.   20. The method of manufacturing a light emitting element assembly according to claim 19, wherein a metal layer for alloying is formed in a region of a projected image of the light emitting element vertically projected onto the substrate. (A) A conductive fixing member precursor layer is formed on the connection portion provided in the light emitting element, and then
(B) After arranging the light emitting element on the wiring so that the conductive fixing member precursor layer is in contact with the wiring provided on the substrate, the conductive fixing member precursor layer is heated to obtain the conductive fixing member layer. Then, the connection part of the light emitting element is fixed to the wiring through the conductive fixing member layer.
Consisting of processes,
The method of manufacturing a light-emitting element assembly, wherein the conductive fixing member precursor layer is made of a solution-type conductive material.   In the step (B), in a state where the conductive fixing member precursor layer formed on the connection portion provided in the light emitting element supported on the substrate is in contact with the wiring provided on the base, The method for manufacturing a light-emitting element assembly according to claim 21, wherein the light-emitting element is disposed on the wiring by being removed from the substrate. The method of manufacturing a light-emitting element assembly according to claim 21, wherein the conductive fixing member precursor layer does not contain fine particles having a particle size exceeding 1 x ^10-7 m.   The method of manufacturing a light emitting device assembly according to claim 21, wherein the conductive fixing member layer is made of ITO or IZO.   During the step (B) or after the step (B), by heat treatment, the metal constituting the wiring and the metal constituting the conductive fixing member layer are alloyed, or the connection portion of the light emitting element is constituted. Alloying between the metal forming the conductive fixing member layer and the metal forming the wiring, or alloying between the metal forming the wiring and the metal forming the conductive fixing member layer, and the metal forming the connection portion of the light emitting element and the conductive The method of manufacturing a light-emitting element assembly according to claim 21, wherein alloying with a metal constituting the conductive fixing member layer is achieved.   26. The method of manufacturing a light-emitting element assembly according to claim 25, wherein a metal layer for alloying is formed in a region of a projection image of the light-emitting element vertically projected onto the substrate. The connection part of the light emitting element and the wiring formed on the base are fixed by the conductive fixing member layer,
There is a conductive fixing member layer only below the light emitting element,
The light-emitting element assembly, wherein the conductive fixing member layer is made of ITO or IZO. The connection part of the light emitting element and the wiring formed on the base are fixed by the conductive fixing member layer,
The conductive fixing member layer is composed of at least a metal atom, a carbon atom, and an oxygen atom.

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