JP2003347524A - Transferring method of element, arraying method of element, and manufacturing method of image display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transferring method of an element for making uniform the film thickness of resin for covering the element and accurately transferring the element, and to provide an arraying method of an element and a manufacturing method of an image display. <P>SOLUTION: In the transferring method of the element, the element is transferred to an adhesive layer in a semihardening adhesive layer where the viscous property of the surface where the element is adhered is maintained. Then, heat treatment is made to stick the element to the semihardening adhesive layer, thus transferring the element to the adhesive layer having nearly uniform film thickness, and reducing the misalignment of the element. Especially, when a light-emitting device is handles as a chip covered with the adhesive layer, variation in light transmission properties can be reduced, and quality in the image display where the light-emitting device is transferred and packaged or the like can be improved. <P>COPYRIGHT: (C)2004,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for transferring a device,
The present invention relates to an element arranging method and an image display device manufacturing method.
More particularly, the present invention relates to an element transfer method, an element arrangement method, and an image display device manufacturing method capable of transferring elements with high accuracy.

[0002]

2. Description of the Related Art Conventionally, when light emitting elements are arranged in a matrix and assembled into an image display device, a substrate such as a liquid crystal display (LCD) or a plasma display panel (PDP) is conventionally used. Elements are formed directly on top of each other, or a single LED package is arranged like a light emitting diode display (LED display). For example, in image display devices such as LCD and PDP,
Since the elements cannot be separated, each element is usually formed at an interval of the pixel pitch of the image display device from the beginning of the manufacturing process.

On the other hand, in the case of an LED display, L
An ED chip is taken out after dicing, and individually connected to an external electrode by wire bonding or bump connection by flip chip, and packaged. In this case, the pixels are arranged at a pixel pitch as an image display device before or after packaging, but this pixel pitch is independent of the element pitch at the time of element formation.

LED (Light Emitting Diode) as a Light Emitting Element
Is expensive, an image display device using LEDs can be manufactured at low cost by manufacturing a large number of LED chips from a single wafer. That is, if an LED chip having a size of about 300 μm square is changed to an LED chip of several tens μm square and connected to manufacture an image display apparatus, the price of the image display apparatus can be reduced.

[0005]

By the way, regarding a manufacturing process for manufacturing a required apparatus by rearranging a plurality of elements formed on an element forming substrate on an apparatus substrate, an element holding substrate for temporarily holding elements is provided. An element arranging method is performed in which elements are arranged by transferring the elements to the formed adhesive layer and then transferring the elements to an apparatus substrate as a final placement destination.
As the resin (adhesive) constituting the adhesive layer, a thermosetting resin, for example, an adhesive mainly composed of a resin having excellent heat resistance and chemical resistance such as an epoxy resin can be used. Because it is, it is not easy to handle. For example,
An adhesive layer formed by applying a liquid adhesive on the element holding substrate for temporarily holding the element, for example, 10 mm in length,
When transferring an element having a thickness of about 0.01 mm formed on an element formation substrate having a width of 5 mm, the element may be buried in the adhesive layer.

In addition, when the element is transferred to the uncured adhesive layer, the adhesive layer pressed by the element is deformed, and it is difficult to transfer the element to the adhesive layer with high accuracy. There is also a method of applying a transparent tape made of PET resin to the element holding substrate and applying an adhesive thereon to form an adhesive layer. However, since the uncured adhesive layer is soft, the element is transferred. The adhesive layer is easily deformed with respect to the applied stress, and the position of the transferred element is easily displaced.

Furthermore, when forming an adhesive layer by applying a liquid adhesive to a substrate, it is difficult to make the thickness of the adhesive layer constant, resulting in variations in film thickness. Therefore, when the element is peeled off from the substrate together with the adhesive layer, and the chip is covered with the adhesive layer and the element is handled, a via hole for electrically connecting the element included in the chip and the drive circuit is provided. It may be difficult to form the adhesive layer with high accuracy.

As for the quality of the element, for example, when the element is hardened with resin (adhesive) to make an LED chip, if the element is simply transferred to an uncured adhesive layer, the deformation of the adhesive layer that occurs during transfer In addition, the film thickness of the adhesive layer covering the element is not uniform due to the embedding of the element in the adhesive layer, leading to a decrease in the dimensional accuracy and quality of the chip. In particular, when the element is a light emitting element, the light transmittance varies due to the variation in the film thickness of the adhesive layer, leading to a decrease in the image quality of an image display device configured by arranging LED chips. In addition, there is a problem in that the adhesive strength between the adhesive layer and the element varies due to variations in the thickness of the adhesive layer.

Accordingly, in view of the above-mentioned manufacturing process and quality problems, the present invention can make the film thickness of the resin covering the element uniform and transfer the element with high accuracy. It is an object of the present invention to provide a transfer method, an element arrangement method, and an image display device manufacturing method.

[0010]

The element transfer method of the present invention comprises a step of coating and forming an adhesive layer, a first heat treatment step of heat-treating the adhesive layer to make it semi-cured, and adhesiveness. An element transfer step of transferring an element to the surface of the adhesive layer maintained at a low temperature, and a second heat treatment step of heat-treating the adhesive layer in a semi-cured state to a cured state. To do. By making the adhesive layer semi-cured,
The adhesiveness of the surface to which the element is bonded can be maintained, and deformation of the adhesive layer in the film thickness direction and the surface in-plane direction can be reduced when the element is transferred. Therefore, the film thickness of the adhesive layer can be made substantially uniform, and the positional deviation of the element can be reduced. further,
Even when a chip is formed by covering the element with an adhesive layer,
Chip dimensional variation can be reduced. In particular, in the case of a light emitting element, it is possible to reduce variation in light transmittance due to variation in film thickness of the adhesive layer, and to improve the quality of an image display device in which the light emitting element is transferred and mounted. It becomes possible.

The element arranging method of the present invention is an element arranging method in which a plurality of elements arranged on a first substrate are rearranged on a second substrate, wherein the elements are arranged on the first substrate. A first transfer step in which the element is transferred so that the element is separated from the formed state and the temporary holding member holds the element; and the element held by the temporary holding member is further separated A second transfer step of transferring onto the second substrate, and in the first transfer step or the second transfer step, the element is transferred to an adhesive layer in which adhesiveness is maintained, and the adhesive layer The element is fixed to an adhesive layer that is cured by heat-treating. Therefore, when transferring the elements so as to be separated from each other, the elements are hardly displaced, and the elements can be arranged with high accuracy.

The image display device manufacturing method of the present invention is a method for manufacturing an image display device in which light emitting elements are arranged in a matrix, and is separated from the light emitting elements arranged on a first substrate. A first transfer step of transferring the light emitting element so as to hold the light emitting element on the temporary holding member, and further separating the light emitting element held on the temporary holding member on the second substrate. A second transfer step of transferring the light-emitting element to the adhesive layer, wherein the light-emitting element is transferred to the adhesive layer in which the adhesiveness is maintained, and the adhesive layer is heat-treated in the first transfer step or the second transfer step. The image display surface is formed by fixing the light emitting element to an adhesive layer that is cured by the above. By reducing the variation in the thickness of the resin layer that covers the light-emitting element, light emitted from the light-emitting element can be uniformly extracted to the outside, and a high-quality image display device can be provided.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an element transfer method, an element arrangement method and an image display apparatus manufacturing method according to the present invention will be described with reference to the drawings. First, the element transfer method of the present invention will be described in detail with reference to FIGS.

As shown in FIG. 1, an adhesive layer 1 is formed on an element holding substrate 3 with a release layer 2 interposed therebetween. Element holding substrate 3
Is a substrate having required rigidity, and various substrates such as a semiconductor substrate, a quartz glass substrate, a plastic substrate, and a metal substrate can be used. As will be described later, the adhesive layer 1 holds the element and covers the element so that the element can be formed into a chip shape. The adhesive layer 1 can be formed of a thermosetting resin such as an epoxy resin,
When the element bonded to the adhesive layer 1 is a light emitting element, it is desirable to form the light emitting element with an adhesive having light transmittance so as not to block light emitted from the light emitting element. Further, by forming the adhesive layer 1 on the surface of the release layer 2 formed on the element holding substrate 3, it becomes possible to separate the element from the element holding substrate 3 in a process described later. If the release layer 2 is also formed of a resin having optical transparency such as polyimide, the light emitted from the light emitting element is not blocked. Therefore, even when the light emitting element is formed into a chip shape covered with the adhesive layer 1 and the release layer 2, light emitted from the light emitting element can be taken out to the outside of the chip with almost no damage.

The method for forming the adhesive layer 1 by applying an adhesive is not particularly limited, and the adhesive layer 1 can be formed by a screen printing method or the like. In the case of a relatively high viscosity, the adhesive layer 1 having a substantially uniform film thickness can be formed by applying an adhesive using spin coating or the like. In this example, the adhesive layer 1 is formed by applying an adhesive having a viscosity of about 1000 cps to the element holding substrate 3 having an outer shape of 40 mm and a thickness of 1 mm by spin coating. As a condition for forming the adhesive layer 1 by spin coating, an adhesive can be applied for 30 seconds at a rotation speed of a spin coater of 1000 rpm, and the entire adhesive layer 1 can be formed to have a film thickness of about 20 μm. Further, not limited to this example, the adhesive layer 1 can be formed substantially uniformly so as to have a required film thickness by changing the rotation speed and application time of the spin coater.

Next, as shown in FIG. 2, the adhesive layer 1 is heated at a temperature lower than the curing temperature of the adhesive to maintain the tackiness of the surface 4a and the inside thereof is in a cured state. Layer 4 is formed. In forming the semi-cured adhesive layer 4, for example, when the curing temperature of the adhesive is 130 ° C., by heating it at 110 ° C., which is 20 ° C. lower than the curing temperature, using a circulation oven for 15 minutes, A semi-cured adhesive layer 4 can be formed. Moreover, the heating temperature and the heating time when forming the semi-cured adhesive layer 4 are not limited to the heating temperature and the heating time of this example, and may be set according to the type of the adhesive forming the adhesive layer 1. good. Further, the heating method is not limited to the circulation type oven, and the adhesive layer 1 can be heated to a semi-cured state by various heating methods such as heating by irradiating infrared rays.

Subsequently, as shown in FIG. 3, the semi-cured adhesive layer 4 is brought into contact with a plurality of elements 6 arranged on the substrate 5, and the elements 6 are bonded to the surface 4a. For example, length 10mm, width 5m
The element 6 having a height of 0.01 mm arranged on the sapphire substrate 5 having a size of m is pressed against the semi-cured adhesive layer 4 in a state where the sapphire substrate 5 is placed on a Teflon (registered trademark) sheet. The semi-cured adhesive layer 4 is hardly deformed when the element 6 is pressed against the semi-cured adhesive layer 4 because the inside is in a cured state. Therefore, compared with the case where the uncured adhesive layer is in contact with the element,
The positional deviation of the element 6 and the film thickness variation of the adhesive layer 1 hardly occur, and air is hardly involved between the semi-cured adhesive layer 4 and the element 6, and the adhesive layer is cured, and the element It is possible to reduce the formation of defects such as bubbles that degrade the quality of the element 6 at the boundary between the element 6 and the adhesive layer when the chip 6 is formed into a chip shape coated with the adhesive layer.

The elements 6 are formed on the sapphire substrate 5 so as to be arranged in a matrix. Element 6
Is a light emitting element diode made of a nitride semiconductor material such as gallium nitride, and has a double hetero structure in which an active layer is sandwiched between clad layers as an example. The element 6 has a substantially flat plate shape, and the active layer and the clad layer of the element 6 are extended in a plane parallel to the C surface, which is the main surface of the sapphire substrate 5 on which the active layer and the clad layer are grown, and are selectively grown. Is formed by laminating a gallium nitride crystal layer or the like. In the stage of FIG. 3, the light emitting region is formed, but the final wiring is not formed.

Further, it is preferable that the surface of the element 6 in contact with the semi-cured adhesive layer 4 is substantially flat, and the semi-cured adhesive is obtained by adhering the adhesive surface 4 a and the substantially flat upper surface of the element 6. The element 6 can be held in the layer 4. The element 6 is separated for each element and formed on the sapphire substrate 5, and can be separated by, for example, RIE (reactive ion etching) or the like when separating each element. In this example, the element 6 has a substantially flat shape, but may be an element having an inclined crystal layer inclined with respect to the main surface of the sapphire substrate 5.
Is an element composed of an active layer and a clad layer having a crystal plane parallel to the S plane ((1-101) plane) inclined with respect to the C plane, which is the main surface of the sapphire substrate 5, for example. It is also possible to transfer the chip as a chip coated with a resin so as to cover. Further, after the element 6 is formed on the sapphire substrate 5, it may be placed on another substrate and transferred to the semi-cured adhesive layer 4.

Subsequently, as shown in FIG. 4, the element 6 is separated from the sapphire substrate 5 with the element 6 adhered to the semi-cured adhesive layer 4. When separating the element 6 from the sapphire substrate 5, laser light such as excimer laser or YAG laser is irradiated from the back surface of the sapphire substrate 5 to cause laser ablation at the interface between the element 6 and the sapphire substrate 5. Laser ablation means that a fixing material that absorbs irradiated light is excited photochemically or thermally, and its surface or internal atoms or molecules are cut off and released, mainly all or part of the fixing material. Appears as a phenomenon that causes phase changes such as melting, evaporation, and vaporization. By this laser ablation, a GaN-based material is decomposed into metal Ga and nitrogen at the interface between the element 6 and the sapphire substrate 5 to generate gas. For this reason, the element 6 can be peeled relatively easily. As the laser beam to be irradiated, an excimer laser is preferably used since it has a high output particularly in a short wavelength region, and an instantaneous process is possible, and the element 6 can be transferred quickly.

Next, the entire semi-cured adhesive layer 4 is cured by heating the semi-cured adhesive layer 4 to form a cured adhesive layer. As shown in FIG. 7
Secure to a. In the case of this example, the semi-cured adhesive layer 4 can be cured by heating the semi-cured adhesive layer 4 at, for example, 130 ° C., which is the curing temperature of the adhesive, for 25 minutes. is there. At this time, the element 6 can be buried in the cured adhesive layer 7 only by 1 μm or less, and the positional deviation can be made 1 μm or less. Accordingly, when the height of the element 6 is about several tens of μm, the element 6 is transferred without being buried in the semi-cured adhesive layer 4.

Accordingly, since the adhesive layer can have a substantially uniform film thickness, not only the dimensional variation of the chip formed by coating the element with the adhesive layer can be reduced, but also the adhesive layer. Variation in light transmittance caused by variation in film thickness of the light emitting element can be reduced, and deterioration in image quality of an image display device in which a chip including a light emitting element is disposed can be suppressed.

Furthermore, also in the manufacturing process, when an electrode is formed on an element coated with a resin, a hole such as a via hole can be accurately formed in the resin, and the dimensional variation in the depth direction of the via hole is reduced. It becomes possible. In addition, by reducing the film thickness variation of the adhesive layer, it becomes possible to reduce the adhesive strength variation due to the film thickness of the adhesive layer, and to make the adhesive strength between the element and the adhesive layer uniform. Can also improve the quality of the chip.

In this example, the case of transferring a planar type element has been described. However, the shape of the element is not limited to a substantially flat type element such as a planar type, and an element having another shape may be used. In the case of an element having a shape other than a flat plate shape, it is easy to handle by coating the device with a resin so as to form a substantially flat chip, and the chip is adhered to a semi-cured adhesive layer and transferred together with the chip. This makes it possible to easily transfer the chip.

Next, an element arrangement method and an image display manufacturing method to which the element transfer method of the present invention is applied will be described.

First, the basic structure of the element arrangement method by the two-stage expansion transfer method will be described. The element arrangement method by the two-stage enlargement transfer method is a temporary holding member in which an element formed on the first substrate with a high degree of integration is separated from the element arrangement state on the first substrate. Next, two-stage enlarged transfer is performed in which the element held on the temporary holding member is further separated and transferred onto the second substrate. In this example, the transfer is performed in two stages. However, the transfer can be performed in three or more stages depending on the degree of enlargement in which the elements are spaced apart.

FIG. 6 is a diagram showing the basic steps of the two-stage enlarged transfer method. First, elements 12 such as light emitting elements are densely formed on the first substrate 10 shown in FIG. By forming the elements densely, the number of elements generated per substrate can be increased, and the product cost can be reduced. The first substrate 10 is a substrate capable of forming various elements such as a semiconductor wafer, a glass substrate, a quartz glass substrate, a sapphire substrate, and a plastic substrate, but each element 12 is formed directly on the first substrate 10. Alternatively, it may be an array of those formed on another substrate.

Next, as shown in FIG. 6B, each element 12 is transferred from the first substrate 10 to a temporary holding member, and each element 12 is held on the temporary holding member. At this time, the resin around the element is simultaneously coated for each element 12.
The resin coating around the element is formed to facilitate the formation of an electrode pad and facilitate the handling in the transfer process. The adjacent elements 12 are selectively separated by, for example, transfer between a plurality of temporary holding members.
Finally, they are separated on the temporary holding member and arranged in a matrix as shown in the figure. That is, the element 12 is transferred so as to extend between the elements in the x direction, but is also transferred so as to extend between the elements in the y direction perpendicular to the x direction. The distance that is separated at this time is not particularly limited, and can be a distance that takes into consideration the formation of the resin portion and the formation of the electrode pad in the subsequent process as an example.

After such a first transfer step, FIG.
As shown in FIG. 1, the element 1 existing on the temporary holding member 11
Since 2 is separated, an electrode pad is formed for each element 12. As will be described later, since the electrode pad is formed after the second transfer step in which the final wiring is continued, the electrode pad is formed in a relatively large size so that no wiring defect occurs at that time. Note that the electrode pads are not shown in FIG. Resin-forming chips 14 are formed by forming electrode pads on the respective elements 12 solidified with the resin 13. The element 12 is located in the approximate center of the resin-formed chip 14 on a plane, but may be present at a position deviated toward one side or corner.

Next, as shown in FIG. 6D, a second transfer step is performed. In the second transfer step, the elements 12 arranged in a matrix on the temporary holding member 11 are transferred onto the second substrate 15 so as to be further separated from each other with the resin forming chip 14. Also in the second transfer step, the adjacent elements 12 are separated from each other with the resin forming chip 14 and arranged in a matrix as shown in the figure. That is, the element 12 is transferred so as to extend between the elements in the x direction, but is also transferred so as to extend between the elements in the y direction perpendicular to the x direction. If the position of the element arranged in the second transfer process is a position corresponding to the pixel of the final product such as an image display device, an approximately integer multiple of the pitch between the original elements 12 is arranged in the second transfer process. The pitch of the elements 12 is obtained.
Here, assuming that the expansion rate of the separated pitch from the first substrate 10 to the temporary holding member 11 is n, and the expansion rate of the spaced pitch from the temporary holding member 11 to the second substrate 15 is m,
A value E that is substantially an integer multiple is represented by E = n × m.

Wiring is applied to each element 12 separated from the resin-formed chip 14 on the second substrate 15. This time,
Wiring is performed while suppressing connection failures as much as possible by using the electrode pads formed in advance. This wiring is, for example, the element 12
In the case of a light emitting element such as a light emitting diode,
In the case of a liquid crystal control element, including wiring to the n electrode, selection signal lines, voltage lines, wirings such as alignment electrode films, and the like are included.

In the two-stage enlargement transfer method shown in FIG. 6, the electrode pad can be formed using the spaced space after the first transfer, and the wiring is applied after the second transfer. Then, wiring is performed while using the previously formed electrode pads or the like to suppress connection failures as much as possible. Therefore,
The yield of the image display device can be improved. Further, in the two-stage enlargement transfer method of this example, the process of separating the distance between the elements is two processes, and the number of times of transfer is actually increased by performing such multiple processes of separating the distance between the elements. Will be reduced. That is, for example, the expansion rate of the pitch from the first substrate 10 to the temporary holding member 11 is 2 (n = 2), and the pitch from the temporary holding member 11 to the second substrate 15 is increased. Rate is 2 (m =
Assuming 2), if the image is to be transferred to an enlarged range by one transfer, the final enlargement ratio is 4 × 2 × 2, and the transfer of the square 16 times, that is, the alignment of the first substrate 16 times. Although necessary, in the two-stage enlargement transfer method of this example, the number of alignments is an enlargement ratio of 2 in the first transfer process.
Thus, a total of 8 times, which is simply the addition of 4 times of the square of 4 and 4 times of the square of the enlargement ratio 2 in the second transfer step, is sufficient. That is,
If the same transfer magnification is intended, (n + m) ²
= N ² +2 nm + m ² , so that the number of times of transfer can always be reduced by 2 nm. Therefore,
The manufacturing process also saves time and money by the number of times, which is particularly beneficial when the expansion rate is large.

In the two-stage enlarged transfer method shown in FIG. 6, the element 12 is, for example, a light emitting element. However, the present invention is not limited to this, and other elements such as a liquid crystal control element, a photoelectric conversion element, a piezoelectric element, and a thin film transistor. Element, thin film diode element, resistance element, switching element, micro magnetic element,
It may be an element selected from micro optical elements, a portion thereof, a combination thereof, or the like.

In the second transfer step, the light emitting element is handled as a resin-formed chip and is transferred onto the second substrate from the temporary holding member. Refer to FIGS. 7 and 8 for the resin-formed chip. I will explain. The resin-formed chip 14 is obtained by hardening the periphery of the element 12 that is spaced apart with the resin 13, and the resin-formed chip 14 transfers the element 12 from the temporary holding member to the second substrate. It can be used in some cases. The resin-formed chip 14 has a substantially square shape on a substantially flat plate.
The shape of the resin-forming chip 14 is a shape formed by solidifying the resin 13. Specifically, an uncured resin is used for each element 1.
2 is applied to the entire surface so as to include 2, and after curing, the edge portion is cut by dicing or the like.

Electrode pads 16 and 17 are formed on the front side and the back side of the substantially flat resin 13, respectively. The electrode pads 16 and 17 are formed over the entire surface.
A conductive layer such as a metal layer or a polycrystalline silicon layer as a material 17 is formed and patterned into a required electrode shape by a photolithography technique. These electrode pads 16 and 17 are formed so as to be connected to the p electrode and the n electrode of the element 12 which is a light emitting element, respectively.
If necessary, a via hole or the like is formed in the resin 13.

Here, the electrode pads 16 and 17 are formed on the front surface side and the back surface side of the resin forming chip 14, respectively, but it is possible to form both electrode pads on one surface. In some cases, since there are three electrodes of source, gate and drain, three or more electrode pads may be formed. Electrode pad 16,
The reason why the position 17 is shifted on the flat plate is to prevent overlapping even if contacts are taken from the upper side when the final wiring is formed. The shape of the electrode pads 16 and 17 is not limited to a square, and may be other shapes.

By constructing such a resin-formed chip 14, the periphery of the element 12 is covered with the resin 13, and the electrode pads 16 and 17 can be formed with high precision by flattening. 16, 17
When the transfer in the next second transfer step is advanced by a suction jig, the handling becomes easy. As described below,
Since the final wiring is performed after the second transfer process that follows,
By performing wiring using the electrode pads 16 and 17 having a relatively large size, wiring defects can be prevented in advance.

Next, FIG. 9 shows a structure of a light emitting element as an example of an element used in the two-stage expansion transfer method of this example. FIG. 9A is an element cross-sectional view, and FIG. 9B is a plan view. This light-emitting element is a GaN-based light-emitting diode,
For example, an element that is crystal-grown on a sapphire substrate. In such a GaN-based light emitting diode, laser ablation occurs due to laser irradiation that passes through the substrate, and film peeling occurs at the interface between the sapphire substrate and the GaN-based growth layer due to the phenomenon of nitrogen vaporization of GaN, It has a feature that element isolation can be made easy.

First, with respect to the structure, a hexagonal pyramid-shaped GaN layer 22 selectively formed on an underlying growth layer 21 made of a GaN-based semiconductor layer is formed. Note that an insulating film (not shown) exists on the underlying growth layer 21, and the hexagonal pyramid-shaped GaN layer 22 is formed by MOCVD at the opening of the insulating film.
It is formed by law. The GaN layer 22 is a pyramidal growth layer covered with an S plane ((1-101) plane) when the main surface of a sapphire substrate used during growth is a C plane, and is doped with silicon. It is an area. The inclined S-plane portion of the GaN layer 22 functions as a double heterostructure cladding. An InGaN layer 23, which is an active layer, is formed so as to cover the inclined S-plane of the GaN layer 22, and a magnesium-doped GaN layer 24 is formed on the outside thereof. This magnesium-doped GaN layer 24 also functions as a cladding.

Such a light emitting diode has a p-electrode 2
5 and an n-electrode 26 are formed. The p-electrode 25 is a Ni / P formed on the magnesium-doped GaN layer 24.
It is formed by vapor deposition of a metal material such as t / Au or Ni (Pd) / Pt / Au. The n-electrode 26 is formed by evaporating a metal material such as Ti / Al / Pt / Au at a portion where the insulating film (not shown) is opened. The underlying growth layer 2
In the case where the n electrode is taken out from the back side of 1, the formation of the n electrode 26 is not necessary on the surface side of the underlying growth layer 21.

The GaN-based light emitting diode having such a structure is an element capable of emitting blue light, and can be peeled off from the sapphire substrate relatively easily by laser ablation, and selectively irradiates a laser beam. Thus, selective peeling is realized. The GaN-based light emitting diode may have a structure in which an active layer is formed on a flat plate or in a strip shape, or may have a pyramid structure in which a C surface is formed at the upper end. Further, other nitride-based light emitting elements, compound semiconductor elements, and the like may be used.

Subsequently, a specific method of the manufacturing method of the image display device to which the element arrangement method shown in FIG. 6 is applied will be described. As the light emitting element, the GaN-based light emitting diode shown in FIG. 9 is used. First, as shown in FIG. 10, a plurality of light emitting diodes 42 are densely formed on the main surface of the first substrate 41. The size of the light emitting diode 42 can be very small, for example, about 20 μm on a side. As the constituent material of the first substrate 41, a material having a high transmittance with respect to the wavelength of the laser irradiated to the light emitting diode 42, such as a sapphire substrate, is used. The light-emitting diode 42 is formed up to the p-electrode and the like, but the final wiring has not been made yet, and an inter-element separation groove 42g is formed so that the individual light-emitting diodes 42 can be separated. The groove 42g is formed by reactive ion etching, for example.

Next, the light emitting diode 42 on the first substrate 41 is transferred onto the first temporary holding member 43. Here, examples of the first temporary holding member 43 include a glass substrate,
A quartz glass substrate, a plastic substrate, or the like can be used. In this example, a quartz glass substrate is used. A release layer 44 that functions as a release layer is formed on the surface of the first temporary holding member 43. For the release layer 44, a fluorine coat, a silicone resin, a water-soluble adhesive (for example, polyvinyl alcohol: PVA), polyimide, or the like can be used. Here, polyimide is used.

At the time of transfer, as shown in FIG. 10, an adhesive (for example, an ultraviolet curable adhesive) 45 sufficient to cover the light emitting diode 42 is applied on the first substrate 41 and supported by the light emitting diode 42. In this manner, the first temporary holding member 43 is overlapped. In this state, as shown in FIG. 11, the adhesive 45 is irradiated with ultraviolet rays (UV) from the back surface side of the first temporary holding member 43 to be cured. The first temporary holding member 43 is a quartz glass substrate, and the ultraviolet rays pass through the first temporary holding member 43 to quickly cure the adhesive 45. At this time, the first temporary holding member 43 is a light emitting diode 42.
Are supported by the first substrate 41 and the first
The space between the temporary holding member 43 and the light-emitting diode 42
It depends on the height of the. As shown in FIG. 11, if the adhesive 45 is cured in a state where the first temporary holding member 43 is overlapped so as to be supported by the light emitting diode 42, the thickness t of the adhesive 45 is equal to the first substrate. It is regulated by the distance between 41 and the first temporary holding member 43, and is regulated by the height of the light emitting diode 42.
That is, the light emitting diode 42 on the first substrate 41 serves as a spacer, and an adhesive layer having a certain thickness is formed between the first substrate 41 and the first temporary holding member 43. Become. Thus, in the above method, since the thickness of the adhesive layer is determined by the height of the light emitting diode 42, it is possible to form an adhesive layer having a constant thickness without strictly controlling the pressure.

After the adhesive 45 is cured, a laser is applied to the light emitting diode 42 as shown in FIG.
The light emitting diode 42 is irradiated from the back surface of the first substrate 41.
Is peeled off using laser ablation. GaN
Since the light emitting diode 42 of the system decomposes into metallic Ga and nitrogen at the interface with sapphire, it can be peeled off relatively easily. An excimer laser, a harmonic YAG laser, or the like is used as the laser for irradiation. The light emitting diode 42 is separated at the interface of the first substrate 41 by the peeling using the laser ablation, and is transferred onto the temporary holding member 43 while being embedded in the adhesive 45.

FIG. 13 shows a state in which the first substrate 41 has been removed by the above-described peeling. At this time, the GaN-based light emitting diode is peeled off from the first substrate 41 made of a sapphire substrate with a laser, and Ga 46 is deposited on the peeled surface, so that it is necessary to etch it. Therefore, wet etching is performed with NaOH aqueous solution or dilute nitric acid, and as shown in FIG.
a46 is removed. Further, as shown in FIG. 15, the surface is cleaned by oxygen plasma (O ₂ plasma), the adhesive 45 is cut by dicing grooves 47 by dicing, and after dicing for each light emitting diode 42, the light emitting diode 42 is selectively separated. Do. In the dicing process, dicing using a normal blade is performed, and when a narrow cut of 20 μm or less is required, processing using a laser using the laser is performed. The cut width is the light emitting diode 42 covered with the adhesive 45 in the pixel of the image display device.
As an example, the groove shape is processed by an excimer laser to form the chip shape.

Next, the process of selectively separating the light emitting diode 42 will be described in detail with reference to FIGS. First, as shown in FIG. 16, an adhesive layer formed by applying an adhesive made of a thermosetting resin to the second temporary holding member 49 is heated at a temperature lower than the curing temperature of the adhesive, and semi-cured. A semi-cured adhesive layer 48 in a state is formed. The semi-cured adhesive layer 48 is cured inside while maintaining the adhesiveness on the surface 48a. In order to form the semi-cured adhesive layer 48, in this example, the adhesive layer may be heated at 110 ° C. for about 15 minutes, but it may be set according to the type of adhesive forming the adhesive layer. it can. Here, FIG.
The process shown in FIG. 18 corresponds to the selective transfer process shown in FIG. The second temporary holding member 49 can be a glass substrate, a quartz glass substrate, a plastic substrate, or the like, like the first temporary holding member 43. In this example, a quartz glass substrate is used. . Further, the surface of the second temporary holding member 49 and the adhesive layer 4
A release layer 50 made of polyimide or the like is also formed between the layers 8.

Next, as shown in FIG. 17, the semi-cured adhesive layer 48 is brought into contact with the light emitting diode 42. The light emitting diode 42a to be transferred is irradiated with a laser from the back side of the first temporary holding member 43, and the light emitting diode 42a is peeled off from the first temporary holding member 43 by laser ablation. Thereafter, the second temporary holding member 4
9 is removed from the first temporary holding member 43, FIG.
As shown in FIG. 8, the light emitting diode 4 to be transferred
Only 2a is selectively separated and transferred to the semi-cured adhesive layer 48. At this time, the semi-cured adhesive layer 48 has a surface 48a.
Since the inside is cured while maintaining the adhesive property, the semi-cured adhesive layer 48 is hardly deformed even when the light emitting diode 42 is brought into contact with the surface 48a. Variation in the thickness of the light-emitting diode 42a can be reduced, and the positional displacement of the light-emitting diode 42a in the in-plane direction of the surface 48a hardly occurs.

Further, after the light emitting diode 42a is bonded to the semi-cured adhesive layer 48, the semi-cured adhesive layer 48 can be made into a cured adhesive layer by heating at the curing temperature of the adhesive. In this example, the semi-cured adhesive layer 4 is heated by heating the semi-cured adhesive layer 48 at 130 ° C. for about 25 minutes.
A cured adhesive layer in which 8 is entirely cured can be formed, and can be cured not only inside the semi-cured adhesive layer 48 but also to the surface. Therefore, the light emitting diode 42a transferred to the semi-cured adhesive layer 48 with high accuracy can be fixed to the cured adhesive layer as it is.

After the selective separation, a resin layer 51 is formed by applying a resin so as to cover the transferred light emitting diode 42a as shown in FIG. Here, the applied resin and the cured adhesive layer are integrated to form the resin layer 51. Further, as shown in FIG. 20, the thickness of the resin layer 51 is reduced by oxygen plasma or the like, and as shown in FIG. 21, via holes 52 are formed by laser irradiation at positions corresponding to the light emitting diodes 42a. For the formation of the via hole 52, an excimer laser, a harmonic YAG laser, a carbon dioxide gas laser, or the like can be used. At this time, the via hole 52 has a diameter of about 3 to 7 μm, for example.

Next, an anode side electrode pad 53 connected to the p electrode of the light emitting diode 42 through the via hole 52 is formed. The anode-side electrode pad 53 is
For example, it is formed of Ni / Pt / Au. FIG. 22 shows a state where the anode side electrode pad 53 is formed after the light emitting diode 42a is transferred to the second temporary holding member 49 and the via hole 52 on the anode electrode (p electrode) side is formed.

After the anode electrode pad 53 is formed, a third electrode is formed on the opposite surface to form a cathode electrode.
Is transferred to the temporary holding member 54. The third temporary holding member 54 is also made of, for example, quartz glass. At the time of transfer, as shown in FIG. 23, an adhesive 55 is applied on the light emitting diode 42a on which the anode-side electrode pad 53 is formed, and further on the resin layer 51, and a third temporary holding member 54 is pasted thereon. Match. In this state, when the laser is irradiated from the back surface side of the second temporary holding member 49, the second temporary holding member 49 made of quartz glass and the polyimide formed on the second temporary holding member 49 are used. The light emitting diode 42 formed on the peeling layer 50 is peeled off by laser ablation at the interface of the peeling layer 50 to be formed.
The resin layer 51 is transferred onto the third temporary holding member 54. FIG. 24 shows a state where the second temporary holding member 49 is separated.

In forming the cathode side electrode, the above-mentioned
After the transfer process, the O shown in FIG. ₂By plasma treatment
The peeling layer 50 and the excess resin layer 51 are removed, and the light emitting diode is removed.
Exposing the contact semiconductor layer (n-electrode) of the node 42
The At this time, the steps shown in FIGS.
The cured adhesive layer to which the light emitting diode 42a is transferred
Light-emitting diode because there is almost no variation in film thickness
The peeling layer 50 and the resin layer 51 located on the back side of 42a
It can be removed uniformly. Also, the release layer 50 and the tree
A via hole is formed in the oil layer 51, and the light emitting diode 42a
The light emitting diode is also used for the electrical connection between the
The film thickness variation of the resin layer 51 on the back side of the iodine 42a
Because there is almost no via hole, the light emitting diode 42
It can be formed with high precision so as to reach the back side of a
It becomes. The light emitting diode 42 a is a temporary holding member 54.
Light emitting diode in a state held by adhesive 55
The back side of 42a is on the n electrode side (cathode electrode side)
If the electrode pad 56 is formed as shown in FIG.
The electrode pad 56 is electrically connected to the back surface of the light emitting diode 42a.
Connected to. Thereafter, the electrode pad 56 is patterned.
To do. The electrode pad on the cathode side at this time is, for example, about
It can be 60 μm square. As electrode pad 56
Is a transparent electrode (ITO, ZnO, etc.) or Ti / A
A material such as l / Pt / Au is used. For transparent electrodes
Even if the back surface of the light emitting diode 42a is largely covered, light emission is not caused.
Since there is no gap, patterning accuracy is rough and large.
Electrode formation and the patterning process is easy.
The Next, it was hardened by the resin layer 51 and the adhesive 55
Light-emitting diode 42a is cut out individually, and the resin is formed
Set to chip state. For example, laser cutting
This can be done by FIG. 27 shows the laser dicing.
This shows the cut-out process. Laser dicing
Performed by irradiating a laser line beam
The resin layer 51 and the adhesive 55 are attached to the third temporary holding member.
Cut until 54 is exposed. For this laser dicing
Further, each light emitting diode 42a is formed with a resin having a predetermined size.
Cut out as a chip and transferred to the mounting process described later
The

In the mounting process, the light emitting diode 42a (resin-formed chip) is peeled off from the third temporary holding member 54 by a combination of mechanical means (element suction by vacuum suction) and laser ablation. FIG. 28 shows the light emitting diodes 42 arranged on the third temporary holding members 54.
It is a figure showing a place where a is picked up by adsorption device 57. The suction holes 58 at this time are opened in a matrix at the pixel pitch of the image display device.
A large number of 2a can be adsorbed together. The opening diameter at this time is 600 μm with a diameter of about 100 μm, for example.
Opened in an m-pitch matrix, about 300 at a time
Individual can be adsorbed. The member of the suction hole 58 at this time is, for example, a material produced by Ni electroforming or a hole made by etching a metal plate such as SUS, and a suction chamber 59 is formed in the back of the suction hole 58. And
By controlling the adsorption chamber 59 to a negative pressure, the light emitting diode 42a can be adsorbed. Light emitting diode 42
a is covered with the resin layer 51 at this stage, and its upper surface is substantially flattened. For this reason, selective adsorption by the adsorption device 57 can be easily advanced.

The adsorption device 57 is provided with element position deviation prevention means so that the light emitting diode 42 (resin forming chip) can be stably held at a fixed position during element adsorption by vacuum suction. It is preferable to keep. FIG.
These show an example of the adsorption | suction apparatus 57 which provided the element position shift prevention means 60. FIG. In this example, the element misalignment prevention means 60 is formed as a positioning pin that contacts the peripheral surface of the resin-formed chip, and this is a peripheral surface of the resin-formed chip (specifically, the resin layer 51 cut by laser dicing). The suction device 57 and the resin forming chip (that is, the light emitting diode 42a) are accurately aligned with each other. The cut surface of the resin layer 51 cut by laser dicing is not a complete vertical surface but has a taper of about 5 ° to 10 °. Therefore, if the positioning pin (element position shift prevention means 60) is also provided with the same taper, even if there is a slight position shift between the suction device 57 and the light emitting diode 42a, it is quickly corrected. .

When the light emitting diode 42 is peeled off, the element suction by the suction device 57 and the peeling of the resin-formed chip by laser ablation are combined so that the peeling proceeds smoothly. Laser ablation is performed by irradiating laser from the back side of the third temporary holding member 54. By this laser ablation,
Peeling occurs at the interface between the third temporary holding member 54 and the adhesive 55.

FIG. 30 is a view showing a state where the light emitting diode 42a is transferred to the second substrate 61. As shown in FIG. Second substrate 61
Is a wiring board having a wiring layer 62, and the adhesive layer 63 is applied in advance to the second substrate 61 when the light emitting diode 42a is mounted, and the adhesive layer 63 on the lower surface of the light emitting diode 42 is cured, The light emitting diodes 42 a can be fixedly arranged on the second substrate 61. At the time of this mounting, the suction chamber 59 of the suction device 57 is in a high pressure state, and the suction device 57 and the light emitting diode 42a.
The combined state due to adsorption is released. The adhesive layer 63 can be composed of a UV curable adhesive, a thermosetting adhesive, a thermoplastic adhesive, or the like. The position where the light emitting diode 42 a is arranged on the second substrate 61 is farther than the arrangement on the temporary holding member 54. The energy for curing the resin of the adhesive layer 63 is supplied from the back surface of the second substrate 61. In the case of a UV curable adhesive, the UV irradiation device is used, and in the case of a thermosetting adhesive, only the lower surface of the light emitting diode 42a is cured by infrared heating or the like. In the case of a thermoplastic adhesive, the adhesive is irradiated by infrared rays or laser. Is melted and bonded.

FIG. 31 is a diagram showing a process of arranging the light emitting diodes 64 of other colors on the second substrate 61. If the suction device 57 used in FIG. 27 or FIG. 28 is used as it is and the mounting position of the second substrate 61 is simply shifted to the position of the color, the pixel composed of a plurality of colors with the pixel pitch kept constant. Can be formed. Here, the light emitting diode 42a and the light emitting diode 64 do not necessarily have the same shape. In FIG. 31, the red light-emitting diode 64 has a structure that does not have a hexagonal pyramid GaN layer and is different in shape from the other light-emitting diodes 42a. At this stage, the light-emitting diodes 42 and 64 are already resin-formed chips. Are covered with the resin layer 51 and the adhesive 55, and the same handling is realized regardless of the difference in element structure. Further, since the light emitting diode 64 has a flat plate shape, the light emitting diode 64 may be selectively transferred as it is from the element forming substrate on which the light emitting diode 64 is formed to the semi-cured adhesive layer in a semi-cured state.

Next, as shown in FIG. 32, an insulating layer 65 is formed so as to cover the resin-formed chip including these light emitting diodes 42a and 64. As the insulating layer 65, a transparent epoxy adhesive, a UV curable adhesive, polyimide, or the like can be used. After the insulating layer 65 is formed, a wiring forming process is performed. FIG. 33 is a diagram showing a wiring formation process. Openings 66, 67, 68, 69, 7 in the insulating layer 65
0, 71 are formed, the anode and cathode electrode pads of the light emitting diodes 42, 64 and the wiring layer 62 of the second substrate 61 are formed.
Is a diagram in which wirings 72, 73, and 74 are connected to each other. The opening formed at this time, that is, the via hole can be enlarged because the area of the electrode pad of the light emitting diodes 42 and 64 is increased, and the positional accuracy of the via hole is also coarser than that of the via hole directly formed in each light emitting diode. Can be formed. For example, the via hole at this time is about 20 μm in diameter with respect to an electrode pad of about 60 μm square.
m can be formed. In addition, there are three types of depth of via holes, one connecting to the wiring board, one connecting to the anode electrode, and one connecting to the cathode electrode, so the optimum depth is controlled by controlling the number of laser pulses. .

Thereafter, as shown in FIG.
And the black mask 76 is formed to complete the panel of the image display apparatus. The protective layer 75 at this time is the same as the insulating layer 65 in FIG. Materials such as transparent epoxy adhesive can be used. This protective layer 75 is heated and cured to completely cover the wiring. After this, the driver I
A drive panel is manufactured by connecting C.

In the element arrangement method as described above,
When the light-emitting diode 42 is held by the temporary holding members 49 and 54, the distance between the elements is already increased, and the electrode pads 53 and 5 having a relatively large size are utilized by using the widened distance.
6 or the like can be provided. Since wiring using these relatively large electrode pads 53 and 56 is performed, wiring can be easily formed even when the final device size is significantly larger than the element size. Further, in the method of manufacturing the image display device of this example, the positional deviation can be reduced by transferring the light emitting diode 42 to the semi-cured adhesive layer, and the resin layer film covering the light emitting region of the light emitting diode 42 is used. By reducing the thickness variation, it is possible to reduce the variation in light transmittance. Therefore, the image quality of the image display device formed by disposing the resin forming chip formed by coating the periphery of the light emitting diode 42 with the resin can be improved. In addition, since the dimensional variation of the resin-formed chip can be reduced, the resin-formed chip can be accurately transferred in the transfer process.

[0062]

According to the element transfer method of the present invention, when the element is transferred to the semi-cured adhesive layer, the film thickness variation of the semi-cured adhesive layer hardly occurs when the element is transferred. Therefore, when the semi-cured adhesive layer is cured to form a cured adhesive layer and the chip is formed by covering the element with the cured adhesive layer, the dimensional variation of the chip hardly occurs. In particular, when the device is transferred to the semi-cured adhesive layer, the semi-cured adhesive layer is hardly deformed, and the device can be transferred with almost no displacement of the device. Can be transferred.

Further, according to the element arrangement method of the present invention,
It is possible to easily perform selective transfer so as to separate the elements, and it is possible to easily transfer the elements even when a multi-step transfer process is included. At this time, by transferring the element to the semi-cured adhesive layer, it is possible to transfer the element with high accuracy when transferring the element so as to be separated.

Furthermore, according to the method of manufacturing the image display device of the present invention, the light emitting element can be accurately transferred when the light emitting element is transferred so as to be separated, and the film of the adhesive layer covering the light emitting element. It is possible to reduce the variation in light transmittance caused by the thickness variation, and it is possible to manufacture a high-quality image display device in which unevenness in image quality is reduced.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a device transfer method according to the present invention and is a process sectional view showing a state in which an adhesive layer is formed.

FIG. 2 is a process cross-sectional view illustrating a state in which a semi-cured adhesive layer is formed, illustrating a method for transferring the element.

FIG. 3 is a process cross-sectional view illustrating a state in which a semi-cured adhesive layer is brought into contact with the element, illustrating a method for transferring the element.

FIG. 4 is a process cross-sectional view illustrating a state in which the element is bonded to a semi-cured adhesive layer, illustrating a method for transferring the element.

FIG. 5 is a diagram illustrating a method for transferring the element and is a process cross-sectional view illustrating a state in which a cured adhesive layer is formed.

FIG. 6 is a schematic view showing a method for arranging elements of the present invention.

FIG. 7 is a schematic perspective view of a resin-formed chip.

FIG. 8 is a schematic plan view of a resin-formed chip.

9A and 9B are diagrams illustrating an example of a light-emitting element, in which FIG. 9A is a cross-sectional view, and FIG. 9B is a plan view.

FIG. 10 is a process cross-sectional view showing a first temporary holding member joining process.

FIG. 11 is a process cross-sectional view illustrating a UV adhesive curing process.

FIG. 12 is a process cross-sectional view illustrating a laser ablation process.

FIG. 13 is a process cross-sectional view illustrating a separation process of the first substrate.

FIG. 14 is a process cross-sectional view showing a state where Ga is removed.

FIG. 15 is a process cross-sectional view illustrating a cleaning process for cleaning the lower side of the light emitting element.

FIG. 16 is a process cross-sectional view showing an adhesion process for adhering an element to a semi-cured adhesive layer.

FIG. 17 is a process cross-sectional view illustrating a state where the element is bonded to a semi-cured adhesive layer.

FIG. 18 is a process cross-sectional view illustrating a holding process for holding an element on a second temporary holding member.

FIG. 19 is a process cross-sectional view illustrating a process of embedding a light emitting element with a resin.

FIG. 20 is a process cross-sectional view showing a reduction process for reducing the resin layer thickness.

FIG. 21 is a process cross-sectional view illustrating a via formation process.

FIG. 22 is a process sectional view showing an anode-side electrode pad formation process.

FIG. 23 is a process cross-sectional view showing a laser ablation process.

FIG. 24 is a process sectional view showing a separation process for separating the second temporary holding member.

FIG. 25 is a process cross-sectional view illustrating an exposure process for exposing a contact region of a light emitting element.

FIG. 26 is a process sectional view showing a cathode-side electrode pad forming process.

FIG. 27 is a process sectional view showing a laser dicing process.

FIG. 28 is a process cross-sectional view illustrating a selective pickup process of a light emitting element by an adsorption device.

FIG. 29 is a schematic cross-sectional view showing an example of a suction device provided with element position deviation prevention means.

FIG. 30 is a process cross-sectional view illustrating a transfer process for transferring a resin-formed chip to a second substrate.

FIG. 31 is a process sectional view showing a transfer process for transferring another light emitting diode;

FIG. 32 is a process cross-sectional view illustrating an insulating layer forming process.

FIG. 33 is a process cross-sectional view illustrating a wiring formation process.

FIG. 34 is a process cross-sectional view showing a protective layer and black mask forming process.

[Explanation of symbols]

1 Adhesive Layer 2 Release Layer 3 Element Holding Substrate 4 Semi-cured Adhesive Layer 4a Surface 5 Substrate 6 Element 7 Cured Adhesive Layer 10, 41 First Substrate 11 Temporary Holding Member 12 Element 13 Resin
14 Resin forming chip 15, 61 Second substrate 16 Electrode pad 21 Base growth layer 42 g Groove 42, 42 a
Light-emitting diode 43 Temporary holding member 44, 50 Release layer 45 Adhesive 47 Dicing groove 48 Semi-cured adhesive layer 48a Surface 49 Temporary holding member 51 Resin layer 52 Via hole 53 Anode-side electrode pad 54
Temporary holding member 56 Electrode pad 57 Adsorption device 5
8 Adsorption hole 59 Adsorption chamber 62 Wiring layer 63 Adhesive layer 64 Light emitting diode 65 Insulating layer 66 Opening 72 Wiring 75 Protective layer 76 Black mask

Continued front page    F-term (reference) 2H088 FA18 FA19 HA28 MA20                 5C094 AA42 AA46 BA12 BA25 CA19                       FB06 HA01 HA08 JA01                 5F041 AA37 CA04 CA40 CA46 CA65                       CA74 CA82 CA92 DA13 DA20                       FF06                 5G435 AA17 BB04 CC09 HH20 KK05                       LL06 LL08

Claims (21)

[Claims] 1. A step of applying and forming an adhesive layer; a first heat treatment step of heat-treating the adhesive layer to make it semi-cured; and an element on a surface of the adhesive layer in which adhesiveness is maintained An element transfer method comprising: an element transfer step of transferring; and a second heat treatment step of heat-treating the adhesive layer in a semi-cured state to obtain a cured state. 2. The element transfer method according to claim 1, wherein a heat treatment temperature in the first heat treatment step is lower than a curing temperature of the adhesive layer. 3. The element transfer method according to claim 1, wherein a heat treatment temperature in the second heat treatment step is substantially equal to a curing temperature of the adhesive layer. 4. The element transfer method according to claim 1, wherein the adhesive forming the adhesive layer is a thermosetting resin. 5. The element transfer method according to claim 4, wherein the thermosetting resin is an epoxy resin. 6. The element transfer method according to claim 1, wherein the adhesive layer is light transmissive. 7. The device transfer method according to claim 1, wherein the surface of the adhesive layer is a substantially flat surface. 8. The element transfer method according to claim 4, wherein the adhesive layer is formed by applying the adhesive onto a substrate by a spin coater. 9. The device transfer method according to claim 8, wherein a peeling layer is interposed between the adhesive layer and the substrate. 10. The element transfer method according to claim 1, wherein a main surface of the element in contact with the adhesive layer is substantially flat. 11. The element transfer method according to claim 1, wherein the element has a substantially flat plate shape. 12. The element transfer method according to claim 1, wherein the element is a light emitting element. 13. The device transfer method according to claim 12, wherein the light emitting device is a light emitting diode. 14. The element transfer method according to claim 12, wherein the light emitting element has a nitride semiconductor layer. 15. The crystal layer constituting the light emitting element is made of S.
13. The device transfer method according to claim 12, wherein the device is extended to a surface. 16. The element transfer method according to claim 1, wherein the element is coated with a resin to form a chip. 17. An element arrangement method in which a plurality of elements arranged on a first substrate are rearranged on a second substrate, wherein the elements are separated from a state in which the elements are arranged on the first substrate; A first transfer step of transferring the element so that the element is held on the temporary holding member, and a second transfer step of transferring the element held on the temporary holding member onto the second substrate further apart. A second transfer step, and in the first transfer step or the second transfer step, the element is transferred to an adhesive layer in which adhesiveness is maintained, and the adhesive layer is heat-treated to obtain a cured state. A method for arranging elements, comprising fixing the elements to an adhesive layer. 18. The distance to be separated in the first transfer step is substantially an integral multiple of the pitch of the elements arranged on the first substrate, and the distance to be separated in the second transfer step is the first distance. 18. The element arranging method according to claim 17, wherein the element is arranged at an integral multiple of the pitch of the elements arranged on the temporary holding member in the transfer step. 19. The element arranging method according to claim 17, wherein the element is a semiconductor element formed of a nitride semiconductor. 20. The device includes a light emitting device, a liquid crystal control device, a photoelectric conversion device, a piezoelectric device, a thin film transistor device,
18. The element arrangement method according to claim 17, wherein the element arrangement method is an element selected from a thin film diode element, a resistance element, a switching element, a minute magnetic element, and a minute optical element, or a portion thereof. 21. A method of manufacturing an image display device in which light emitting elements are arranged in a matrix, wherein the light emitting elements are transferred so as to be separated from a state in which the light emitting elements are arranged on a first substrate. A first transfer step of holding the light emitting element on the temporary holding member; and a second transfer step of transferring the light emitting element held on the temporary holding member onto the second substrate further apart. In the first transfer step or the second transfer step, the light-emitting element is transferred to an adhesive layer in which adhesiveness is maintained, and the adhesive layer is cured by heat-treating the adhesive layer. An image display device manufacturing method, wherein the light emitting element is fixed to form an image display surface.