Method for manufacturing bonded light-emitting element wafer and method for transferring micro-LED

Abstract

The present invention is a method for manufacturing a bonded light-emitting element wafer in which a light-emitting element structure to be a micro LED and a substrate to be bonded are bonded by an adhesive, the method comprising the steps of: bonding the light-emitting element structure and the substrate to be bonded by the adhesive to obtain a bonded wafer; a step of optically inspecting a defective portion of the bonded wafer and creating map data for removal; and on the basis of the removal map data, a removal laser is incident on the defective portion of the bonded wafer from the bonded substrate side, the removal laser is absorbed by the portion included in the defective portion of the adhesive, the portion included in the defective portion of the adhesive is sublimated, and the portion included in the defective portion of the bonded wafer is removed. Thus, a portion included in the defective portion in the light-emitting element structure is removed to obtain the bonded light-emitting element wafer. As a result, it is possible to provide a method for manufacturing a bonded light-emitting element wafer in which a defective portion of a light-emitting element structure can be selectively removed to manufacture a bonded light-emitting element wafer.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a junction type light emitting element wafer and a method for transferring a micro LED (light emitting diode). Background Art

[0002] There is currently a technology disclosed for using a BCB (benzocyclobutene) bonded wafer as a wafer for AlGaInP-based micro-LEDs (μ-LEDs).

[0003] In the above-mentioned wafers, when the wafers are bonded to each other, a poor bonding site may be generated due to the surface conditions of the bonding wafer and the bonded wafer or foreign matter existing on the epitaxial layer or the bonding interface.

[0004] In many cases, the poorly bonded portion becomes a convex shape, which causes a decrease in the accuracy of shape or size when manufacturing the device structure, especially when processing using photolithography.

[0005] In addition, when a μ-LED bare die produced from a wafer having such a convex defective portion is transferred to a transfer substrate, the convex portion may cause uneven pressure applied, resulting in transfer failure.

[0006] Therefore, when transferring a device from a wafer on which junction-type μ-LEDs are formed, it is necessary to remove the defective portion that has become a convex shape before transferring.

[0007] In the case of LED bare crystals that were previously based on discrete devices, there are various methods for physically removing defective parts.

[0008] For example, Patent Document 1 discloses a technique for holding a bare crystal by adsorption. However, when holding the bare crystal by adsorption with a plate, it is assumed that the height of the bare crystal is within a certain tolerance range. In the case where a convex portion is generated on the wafer before device manufacturing due to poor bonding, the height of the bare crystal after device processing is uneven. Therefore, in the prior art illustrated here, a bad situation will occur during transfer. In addition, since the transfer is performed at the same time, this is not a technology that can selectively remove bad parts.

[0009] Patent Document 2 discloses a technique for picking up a bare die by electrostatic means, but like Patent Document 1, this method is based on the premise of picking up the bare die by a plate-shaped fixture, and cannot be applied when a convex portion is generated.

[0010] Patent document 3 discloses a technique for optically detecting a defect and mechanically removing a defective die. In order to mechanically remove a defective die, a certain size (150 μm square or more) is required, and this technique cannot be applied to μ-LED die smaller than 100 μm square.

[0011] Furthermore, even if it is assumed that the defective bare die can be picked out by using the improved technology of Patent Document 3, the defective portion is firmly bonded to the bonded wafer due to the BCB, and cannot be mechanically picked out while holding the BCB portion.

[0012] Thus, Patent Documents 1 to 3 do not disclose a technique for selectively removing defective portions in a μ-LED epitaxial layer firmly bonded to a bonded wafer by BCB or a μ-LED bare die that has undergone device processing.

[0013] Patent Documents 4 and 5 disclose technologies for detecting defects mainly caused by foreign matter in organic EL (electroluminescence) and removing them by laser irradiation.

[0014] Patent Document 6 discloses a defective LED removal device that detects and removes defective LED (light emitting diode) chips. In Patent Document 6, a suction nozzle is used to remove LEDs with poor brightness.

[0015] Patent document 7 discloses a method for evaluating LEDs for defects of loss of optical and electrical functions, removing defective LEDs and leaving good LEDs. In the defective LED removal step of Patent document 7, the following steps are performed: using a laser to raise the temperature of the LED to a temperature higher than its evaporation temperature to evaporate the defective LED structure; or applying a laser beam along the crack of the defective LED to cut off the metal substrate. Prior art literature Patent Literature

[0016] Patent Document 1: Japanese Patent Application Publication No. 2021-019162 Patent Document 2: Japanese Patent Application Publication No. 2018-163900 Patent Document 3: Japanese Patent Application Publication No. 2009-21572 Patent Document 4: Japanese Patent Application Publication No. 2004-119243 Patent Document 5: International Publication No. WO2010 / 092749 Patent Document 6: Japanese Patent Application Publication No. 2020-129658 Patent Document 7: Japanese Patent Application No. 2008-527719 Summary of the invention Problems to be solved by the invention

[0017] In most cases, when the starting substrate is removed, the poorly bonded area is manifested as a convex shape on the side where the starting substrate is removed by the epitaxial layer. In particular, the size of the convex poorly bonded area caused by poor curing of BCB is about 100 to 300 μm in height and 500 to 5000 μm in width, which will cause adverse effects during photolithography. When photolithography is performed by contact exposure, since the wafer and the photomask are in close contact in a vacuum state, the mask will deform according to the TTV (Total Thickness Variation: the difference between the maximum and minimum thickness values) of the wafer. If there is a convex poorly bonded area, the incident light of the exposure source becomes obliquely incident, causing the formed pattern to deviate, distort, or become larger from the mask pattern. As a result, the shape of the components, electrodes, protective films, etc. deviates from the design value, resulting in dimensional deviation and positional deviation. When such a component is transferred to the mounting substrate, the deviation from the pattern on the mounting substrate side will reduce the mounting accuracy and increase the defect rate. Deviation from the design value is difficult to detect only by photoluminescence (PL) property inspection or appearance inspection, and abnormalities are sometimes noticed only after installation and power-on. If a defect is recognized after installation, reinstallation work is required, resulting in increased installation costs.

[0018] Furthermore, when the μ-LED bare die manufactured from such a wafer is transferred to the transfer substrate, uneven pressure is applied by the protrusions, which easily leads to transfer failure.

[0019] In addition, the adhesive layer also functions as an adhesive material in the defective part, and the defective part is not peeled off or separated due to vacuum adsorption or the tensile strength of the bonding degree, and the defective part is maintained.

[0020] Furthermore, defective parts are not limited to defective bonding parts, but also include defective parts of device characteristics. Such defective parts of device characteristics are also difficult to detect only through PL characteristic inspection or appearance inspection, just like defective bonding parts. Sometimes, abnormalities are not noticed until after installation and power-on.

[0021] The present invention is completed to solve the above-mentioned problem, and its purpose is to provide a method for manufacturing a bonded light-emitting element wafer and a method for transferring a micro-LED. The manufacturing method can selectively remove defective parts of the light-emitting element structure to become a micro-LED that is bonded to the bonded wafer by an adhesive to manufacture a bonded light-emitting element, and the transfer method can prevent the transfer of defective micro-LEDs. Means of solving problems

[0022] In order to solve the above-mentioned problems, the present invention provides a method for manufacturing a bonded light-emitting element wafer, in which a light-emitting element structure to be a micro-LED is bonded to a bonded substrate that is transparent to the removal laser by an adhesive that absorbs a removal laser. The method comprises the following steps: bonding the light-emitting element structure to the bonded substrate by the adhesive to obtain a bonded wafer; optically inspecting defective parts of the bonded wafer to prepare removal map data; and, based on the removal map data, irradiating the removal laser from the bonded substrate side with respect to the defective part of the bonded wafer, causing a portion of the adhesive contained in the defective part to absorb the removal laser, causing a portion of the adhesive contained in the defective part to sublime, thereby removing a portion of the light-emitting element structure contained in the defective part to obtain the bonded light-emitting element wafer.

[0023] If the manufacturing method of the junction type light emitting element wafer of the present invention is such, it is possible to optically inspect the defective parts of the junction type light emitting element wafer and produce the map data for removal, and selectively remove the defective parts (for example, defective bonding parts and defective parts of element characteristics) in the light emitting element structure contained in the junction type light emitting element wafer by laser irradiation based on the produced map data for removal. In addition, in the manufacturing method of the junction type light emitting element wafer of the present invention, it is possible to simply selectively remove the defective parts of the light emitting element structure without using a mechanical method. That is, according to the manufacturing method of the junction type light emitting element wafer of the present invention, it is possible to simply manufacture a junction type light emitting element wafer in which the defective parts of the light emitting element structure have been removed.

[0024] The present invention preferably performs the following steps in the step of preparing the removal map data: obtaining a photoluminescence spectrum of the bonded wafer, preparing first map data related to the defective portion using the peak wavelength, peak intensity and / or peak half-value width as a judgment basis; and photographing the bonded wafer from the bonded substrate side with a CCD (charge coupled device) camera, preparing second map data related to the defective portion based on the color tone of the image obtained by photographing; and using the first map data and the second map data to prepare the removal map data.

[0025] Based on the removal map data created in this way, all the defective bonding sites and defective device characteristic sites in the light emitting device structure included in the junction type light emitting device wafer can be selectively and reliably removed.

[0026] In this case, for example, the light emitting element structure is subjected to element separation processing, and the removal map data can be created for the bonded wafer including the light emitting element structure subjected to the element separation processing.

[0027] For a bonded wafer including a light emitting element structure that has been separated into elements, the first map data and the second map data can also be prepared, and these map data are synthesized to prepare map data for removal. By doing so, it is possible to simply and selectively remove bad parts of the light emitting element structure without affecting good parts of the light emitting element structure.

[0028] Alternatively, in the step of preparing the removal map data, the following steps are also performed: irradiating the surface of the light-emitting element structure of the bonded wafer with a topology detection laser from an inclined direction to obtain topology data, and preparing topology map data related to the defective portion based on the topology data; using the first map data, the second map data and the topology map data to prepare the removal map data related to the defective portion; after removing the portion of the light-emitting element structure contained in the defective portion, performing element separation processing on the light-emitting element structure.

[0029] When the removal map data is prepared before the element separation process, the topology map data is obtained, and the topology map data is synthesized with the first map data and the second map data to prepare the removal map data, and the removal using the laser is performed based on the removal map data, so that all the poor bonding parts and poor element characteristic parts in the light emitting element structure included in the junction type light emitting element wafer can be selectively and reliably removed. Furthermore, by doing so, the poor lithography accuracy parts around the poor parts of the light emitting element structure can be reduced.

[0030] For example, as the removal laser, a laser having a wavelength of 170 nm to 360 nm can be used.

[0031] The removal laser is not particularly limited as long as it can pass through the bonded substrates and be absorbed by the adhesive, and a laser having a wavelength of 170 nm to 360 nm can be used.

[0032] For example, as the adhesive, an adhesive having a light absorption edge in a wavelength range of 170 nm to 360 nm can be used.

[0033] Such an adhesive can be easily evaporated using a removal laser having a wavelength of 170 nm to 360 nm.

[0034] In this case, as the adhesive, for example, an adhesive selected from the group consisting of benzocyclobutene, silicone resin, epoxy resin, SOG (spin-on-glass), polyimide, and amorphous fluorine-based resin can be used.

[0035] The adhesive is not particularly limited as long as it absorbs the laser light for removal. For example, by using such an adhesive, the light emitting element structure can be firmly bonded to the bonded substrate.

[0036] Before removing the portion of the light emitting element structure included in the defective portion, a protective material is preferably applied to the light emitting element structure.

[0037] Such a protective material can prevent good portions of the light emitting element structure that should not be removed from being damaged by a receiving jig or the like when the bonded wafer is irradiated with laser light.

[0038] As the protective material, a protective material containing polyvinyl acetate or a protective material containing polyvinyl alcohol is preferably used.

[0039] Such a protective material is preferred because it is easily removable.

[0040] In addition, the present invention provides a method for transferring a micro LED, which transfers the micro LED from a bonded light-emitting element wafer containing the micro LED to a transfer substrate, wherein a bonded light-emitting element wafer containing the light-emitting element structure that has undergone the element separation process is manufactured by the method for manufacturing a bonded light-emitting element wafer of the present invention; and the light-emitting element structure that is the micro LED is transferred from the bonded light-emitting element wafer to the transfer substrate.

[0041] As described above, in the method for manufacturing a bonded light-emitting element wafer of the present invention, it is possible to selectively remove defective parts of the light-emitting element structure contained in the bonded light-emitting element wafer (for example, defective bonding parts and defective parts of element characteristics), thereby being able to manufacture a bonded light-emitting element wafer from which defective parts of the light-emitting element structure have been removed. Therefore, according to the method for transferring a micro-LED of the present invention, it is possible to prevent the transfer of defective light-emitting element structures, i.e., defective micro-LEDs. Effects of the Invention

[0042] As described above, the method for manufacturing a junction type light emitting element wafer of the present invention can selectively remove defective parts in the light emitting element structure contained in the junction type light emitting element wafer. That is, according to the method for manufacturing a junction type light emitting element wafer of the present invention, a junction type light emitting element wafer that does not contain defective light emitting element structures can be manufactured.

[0043] In addition, according to the micro LED transfer method of the present invention, it is possible to prevent defective micro LEDs from being transferred. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a schematic flow chart of the method for manufacturing a junction type light emitting element wafer of the present invention. Figure 2 It is a schematic cross-sectional view showing a part of the step of obtaining a bonded wafer in the first embodiment of the method for manufacturing a bonded light-emitting element wafer of the present invention. Figure 3 It is a schematic cross-sectional view showing another part of the step of obtaining a bonded wafer in the first embodiment of the method for manufacturing a bonded light-emitting element wafer of the present invention. Figure 4 It is a schematic cross-sectional view of a bonded wafer obtained in the step of obtaining a bonded wafer in the first embodiment of the method for manufacturing a bonded light-emitting element wafer of the present invention. Figure 5 It is a schematic plan view of a bonded wafer obtained in the step of obtaining a bonded wafer in the first embodiment of the method for manufacturing a bonded light-emitting element wafer of the present invention. Figure 6 It is a schematic cross-sectional view showing a part of the step of obtaining a junction type light emitting element wafer in the first embodiment of the method for manufacturing a junction type light emitting element wafer of the present invention. Figure 7 It is a schematic plan view of a bonding wafer receiving jig used in the first embodiment of the method for manufacturing a bonding type light emitting element wafer of the present invention. Figure 8 It is a schematic cross-sectional view showing another part of the step of obtaining a junction type light emitting element wafer in the first embodiment of the method for manufacturing a junction type light emitting element wafer of the present invention. Fig. 9 This is a part of the removal map data used in the first embodiment of the method for manufacturing a junction-type light-emitting element wafer of the present invention. Fig.10 It is a schematic plan view showing irradiation with a laser beam for removal in the first embodiment of the method for manufacturing a junction-type light-emitting element wafer of the present invention. Fig.11 It is a schematic cross-sectional view showing irradiation with a laser beam for removal in the first embodiment of the method for manufacturing a junction-type light-emitting element wafer of the present invention. Fig.12 It is a schematic plan view of a light emitting element structure after a portion included in a defective portion in the light emitting element structure is removed in the first embodiment of the method for manufacturing a junction type light emitting element wafer of the present invention. Fig.13 It is a schematic cross-sectional view of a junction type light emitting element wafer obtained after removing a portion included in a defective portion in a light emitting element structure in the first embodiment of the method for manufacturing a junction type light emitting element wafer of the present invention. Fig.14 It is a schematic cross-sectional view of a junction type light emitting element wafer after the element separation process in the first embodiment of the method for manufacturing the junction type light emitting element wafer of the present invention. Fig.15 It is a schematic cross-sectional view showing a part of the protective film forming step in the first embodiment of the method for manufacturing a junction-type light-emitting element wafer of the present invention. Fig.16 It is a schematic cross-sectional view of a junction type light emitting element wafer obtained in the first embodiment of the method for manufacturing a junction type light emitting element wafer of the present invention. DETAILED DESCRIPTION

[0045] As described above, it is required to develop a method for manufacturing a bonded light-emitting element wafer and a method for transferring a micro-LED, wherein the manufacturing method can selectively remove defective parts of a light-emitting element structure to become a micro-LED that is bonded to the bonded wafer by an adhesive to manufacture a bonded light-emitting element wafer, and the transfer method can prevent the transfer of defective micro-LEDs.

[0046] As a result of in-depth research and discussion on the above-mentioned problems, the inventors discovered that by optically inspecting defective parts of a bonded wafer to produce removal map data, and by laser irradiation based on the produced removal map data, defective parts in the light-emitting element structure contained in a bonded light-emitting element wafer can be selectively removed, thereby completing the present invention.

[0047] That is, the present invention is a method for manufacturing a bonded light-emitting element wafer, in which a light-emitting element structure to become a micro-LED is bonded to a bonded substrate that is transparent to the removal laser by means of an adhesive that absorbs a removal laser, and the method comprises the following steps: bonding the light-emitting element structure to the bonded substrate by means of the adhesive to obtain a bonded wafer; optically inspecting defective portions of the bonded wafer to produce removal map data; and, based on the removal map data, irradiating the removal laser from the bonded substrate side with respect to the defective portion of the bonded wafer, causing a portion of the adhesive contained in the defective portion to absorb the removal laser, causing a portion of the adhesive contained in the defective portion to sublime, thereby removing a portion of the light-emitting element structure contained in the defective portion to obtain the bonded light-emitting element wafer.

[0048] In addition, the present invention is a method for transferring a micro LED, which transfers the micro LED from a bonded light-emitting element wafer containing the micro LED to a transfer substrate, wherein a bonded light-emitting element wafer containing the light-emitting element structure that has undergone the element separation process is manufactured by the method for manufacturing a bonded light-emitting element wafer of the present invention; and the light-emitting element structure that is the micro LED is transferred from the bonded light-emitting element wafer to the transfer substrate.

[0049] Hereinafter, the present invention will be described in detail with reference to the accompanying drawings, but the present invention is not limited thereto.

[0050] [Method for manufacturing a junction-type light-emitting device wafer] Figure 1 A schematic flow chart showing a method for manufacturing a junction-type light-emitting element wafer of the present invention. The method for manufacturing a junction-type light-emitting element wafer of the present invention generally comprises the following steps: a step of obtaining a junction-type wafer, a step of preparing removal map data, a step of irradiating a removal laser on a defective portion of the junction-type wafer based on the removal map data, and removing a portion of the light-emitting element structure included in the defective portion to obtain a junction-type light-emitting element wafer.

[0051] Hereinafter, a method for manufacturing such a junction type light emitting element wafer will be described with reference to a more detailed specific example.

[0052] (First Embodiment) <Steps for Obtaining Bonded Wafers> First, refer to Figure 2 to Figure 5 The steps of obtaining a bonded wafer in this embodiment will be described.

[0053] First, in Figure 2 After a first conductive type GaAs buffer layer (not shown) is stacked on the first conductive type GaAs starting substrate 1, a 0.1 μm thick first conductive type GaAs layer is grown in sequence. x In 1-x P (0.4 ≤ x ≤ 0.6) first etching stop layer and 0.1 μm thick first conductivity type GaAs second etching stop layer, forming etching stop layer 2. Then, as Figure 2 As shown, an EPW (epitaxial wafer) 100 having a light emitting element structure 3 as an epitaxial functional layer is prepared. The light emitting element structure 3 is sequentially grown on the etching stop layer 2: a first conductivity type (Al y Ga 1-y ) x In 1-x P (0.4≤x≤0.6, 0.6≤y≤1.0) first cladding layer 31, 0.6 μm thick non-doped (Al y Ga 1-y ) x In 1-x P (0.4≤x≤0.6, 0≤y≤0.5) active layer 32, 1.0 μm thick second conductivity type (Al y Ga 1-y ) x In 1-x P (0.4≤x≤0.6, 0.6≤y≤1.0) second cladding layer 33, 0.1 μm thick second conductivity type Ga xIn 1-x P (0.5≤x≤1.0) intermediate layer (not shown) and a second conductivity type GaP window layer 34. Here, the first cladding layer 31 to the second cladding layer 33 is called a DH (double heterogeneous) structure. In addition, the light emitting element structure 3 is an element (bare crystal) to be processed into a micro LED through a subsequent process.

[0054] The film thicknesses exemplified above are only examples, and the film thickness is only a parameter that should be changed according to the operating specifications of the device, and is of course not limited to the film thickness described here. In addition, the concept of the present invention naturally includes the case where each layer is not a single composition layer but a plurality of composition layers having a composition within the exemplified range. In addition, the concept of the present invention naturally includes the case where the level of carrier concentration is not uniform in each layer but has a plurality of levels in each layer.

[0055] The active layer 32 may be composed of a single component, or a structure in which multiple barrier layers and active layers are alternately stacked may have similar functions, and both may be selected.

[0056] Next, benzocyclobutene (BCB) 4 is spin-coated on EPW100 as an adhesive (thermosetting bonding member), and the light-emitting element structure 3 and the sapphire wafer as the bonding substrate 5 are stacked opposite to each other by the adhesive 4, and then thermally pressed to produce a Figure 3 The EPW bonding substrate 200 shown in the figure has the light emitting element structure 3 of the EPW 100 and the sapphire substrate 5 bonded together via the BCB 4. In the present embodiment, when the BCB is applied by spin coating, the designed film thickness of the BCB 4 layer is 0.6 μm.

[0057] In this embodiment, the substrate 5 to be bonded is exemplified as sapphire, but the substrate 5 to be bonded is not limited to sapphire, and any material may be selected as long as the transmittance and flatness to the removal laser described later are ensured. In addition to sapphire, quartz may be selected.

[0058] In this embodiment, BCB 4 is applied in a layered state, but the adhesive 4 is not limited to a layered state. The same result can be obtained even if photosensitive BCB is patterned into isolated islands, lines, or other shapes and then bonded.

[0059] Next, the GaAs starting substrate 1 is removed by wet etching to expose the first etching stop layer, and then the etchant is switched to remove the second etching stop layer. Thus, the etching stop layer 2 is removed to expose the first cladding layer 31. Figure 4 As shown, a bonded wafer (EP bonded substrate) 10 in which the light emitting element structure 3 including the DH layer and the window layer 34 and the bonded substrate 5 are bonded via the adhesive 4 is manufactured.

[0060] In the present embodiment, a BCB thickness of 0.6 μm is exemplified, but the thickness of the adhesive 4 is not limited to this thickness, and the same effect can be obtained even if it is thicker or thinner than this thickness.

[0061] Figure 5 A schematic plan view showing an example of a bonded wafer obtained in the step of obtaining a bonded wafer in the present embodiment. Figure 5 The bonded wafer 10 shown includes the light emitting element structure 3 bonded to the bonded wafer 5 via an adhesive (not shown). The bonded wafer 5 includes a light emitting element structure non-bonded region 51 not bonded to the light emitting element structure 3 at its outer peripheral portion.

[0062] <Steps for creating map data for removal> Next, a step of optically inspecting the defective portion of the bonded wafer 10 and creating map data for removal is performed.

[0063] In this embodiment, first map data on the defective portion, topological map data on the defective portion, and second map data on the defective portion are created, and removal map data on the defective portion is created using these map data.

[0064] Next, the acquisition of each map data will be described.

[0065] [First map data] First, a laser with a wavelength of 325 to 532 nm and a spot diameter of 100 μm is irradiated to the entire area of ​​the bonded wafer 10 at a 25 μm pitch, and a photoluminescence (PL) spectrum is collected to create first map data. The laser wavelength can be selected from any of the above wavelengths. In this embodiment, a solid laser with an oscillation wavelength of 532 nm is used.

[0066] In this embodiment, the design wavelength of EPW100 is designed to be 632nm, and the positions within the range of 632nm±5nm are regarded as qualified points, and the wavelength domain outside this range is regarded as unqualified points, so as to produce the first map data related to the defective parts, especially the defective parts of the component characteristics.

[0067] In this embodiment, the wavelength is exemplified as an inspection item for the defective part, but the judgment criterion is of course not limited to the wavelength alone. In the convex defective part, stress is applied due to deformation in many cases, and sometimes cracks occur. Since the half-value width of the peak value increases due to large stress or the PL intensity is greatly reduced due to cracks, the first map data can also be prepared using the PL intensity or the half-value width as a judgment criterion or as an additional judgment criterion.

[0068] [Topological map data] Relative to Figure 4 The surface of the light emitting element structure 3 side of the bonded wafer 10 is irradiated with a laser having an oscillation wavelength of 532nm from an oblique direction. Using a system that places a light receiver at the same angle as the incident angle of the laser in the direction of reflection, the entire surface of the wafer is irradiated with laser light at a pitch of 25μm, and the deviation of the reflection angle is measured. Since the reflection angle deviates upward in the convex part of the light emitting element structure 3 and deviates downward in the concave part, topological data is collected based on the deviation of the reflection angle. Using the height tolerance as a threshold, topological map data is produced that regards points within the tolerance as qualified points and other points as unqualified points.

[0069] [Second map data] The CCD (charge coupled device) camera is used to monitor the bonding substrate (sapphire substrate) 5 from the bonding substrate side. Figure 4 The bonded wafer 10 is photographed, and qualified and unqualified points are determined based on the color tone. The color tone of unqualified points with poor bonding is often slightly whiter (thinner) than that of evenly bonded points. The pass or fail is determined by the contrast difference, and the second map data related to the defective parts, especially the poorly bonded parts, is produced to determine the pass or fail with a 25μm pitch grid.

[0070] The defective parts of the first map data, topological map data and second map data obtained as above are superimposed to generate map data for removal. Although the positions of the three map grids are not consistent, the area defined as a defective part in any map is defined as a defective part, and map data for removal is generated.

[0071] <Step of irradiating a defective portion of a bonded wafer with a removal laser based on removal map data to remove a portion of the light emitting element structure included in the defective portion to obtain a bonded light emitting element wafer> In this step, refer to Figure 6 to Figure 16 , follow the steps described below to obtain a junction type light emitting element wafer.

[0072] First, if Figure 6 As shown, the protective material 6 is applied to the starting substrate removal surface of the bonded wafer 10. In this embodiment, the protective material 6 is Hogomax (trademark: a material containing propylene glycol monomethyl ether and polyvinyl alcohol listed in the SDS (Safety Data Sheet)) manufactured by DISCO Co., Ltd. by spin coating, but the material of the protective material 6 is not limited to Hogomax, and any material can be selected as long as it has the function of a protective material and is easy to remove. In addition to Hogomax, for example, polyvinyl acetate and polyvinyl alcohol are also suitable for use.

[0073] Next, the bonded wafer 10 coated with the protective material 6 is introduced into the laser processing unit. Figure 7 The bonding wafer receiving jig 7 shown holds the bonding wafer 10 and introduces it into the laser processing section. Figure 7 The bonding wafer receiving jig 7 shown in the figure has an opening area 72 in the center, and the periphery of the opening area 72 forms a wafer receiving groove 71. When held, as shown in FIG. Figure 8 As shown, the light emitting element structure 3 is located in the opening area 72 .

[0074] In addition, when importing, such as Figure 8 As shown, the bonding wafer 10 is introduced with the coated surface of the protective material 6 facing downward. In this embodiment, the case where the coated surface of the protective material 6 faces downward is illustrated, but it is not limited to the downward state, and of course the coated surface can also be set to face upward or to the side. However, in the case where the coated surface of the protective material 6 faces downward, the defective parts removed by the sublimation of the BCB4 layer described later are easily dropped to the lower side of the wafer due to gravity, so it is effective to reduce the amount of debris attached to the coated surface of the protective material 6. However, since the protective material 6 is eventually removed and the debris will also be removed together, it is of course not limited to the introduction method facing downward.

[0075] like Figure 5 As shown, the outer peripheral portion of the bonded wafer 10 has a width of about 1 to 2 mm and is not bonded to the light emitting element structure 3, and has a light emitting element structure non-bonding region 51 exposed by the bonding substrate (sapphire substrate) 5 or the adhesive 4. When the bonded wafer 10 is held with the coated portion of the protective material 6 facing downward, as shown in FIG. Figure 8 As shown, the wafer receiving groove 71 of the bonding wafer receiving jig 7 is designed to abut against the light emitting element structure non-bonding region 51 to hold the wafer.

[0076] Next, based on the previously obtained removal map data, a region defined as a defective portion is irradiated with a removal laser from the bonded substrate (sapphire substrate) 5 side of the bonded wafer 10 .

[0077] Fig. 9 A part of an example of the removal map data is shown. Fig. 9 The removal map data shown is displayed with the defective portion 10A of the bonded wafer 10 as the center. The defective portion 10A includes the defective portion of the light emitting element structure 3 .

[0078] In this embodiment, for the defective part 10A, Fig.10As shown, the laser lift-off method (Laser Lift-Off, LLO) is used to irradiate the removal laser multiple times. As a result, multiple laser irradiation areas (each time) 81 are generated, and a laser irradiation area 82 is generated which can be said to have only the defective part 10A as a whole. From another point of view, the removal laser can be irradiated to all the defective parts 10A of the bonded wafer 10 (including the defective part of the light emitting element structure 3).

[0079] Fig.11 The following state is shown: the removal laser 83 is incident from the bonded substrate 5 side, so that the portion of the BCB (adhesive) 4 included in the defective portion 10A of the bonded wafer 10 absorbs the removal laser 83, and the portion of the BCB4 included in the defective portion 10A sublimates into gas to disconnect the light emitting element structure 3, and the adhesive force of the defective portion of the light emitting element structure 3 caused by the BCB4 to the bonded substrate 5 is reduced, so that the convex defective portion of the light emitting element structure 3 falls. Since the defective portion is cleanly disconnected and falls almost along the direction of the disconnection line, the influence on the adjacent good portion on the light emitting element structure 3 can be suppressed to a minimum.

[0080] That is, by irradiating the defective portion 10A of the bonded wafer 10 with the laser beam for removal, a portion (defective portion) including the defective portion 10A of the bonded wafer 10 in the light emitting element structure 3 can be removed.

[0081] A KrF excimer laser with a wavelength of 248 nm is used as the removal laser 83, but the wavelength is not limited to this. Any laser can be selected as long as it is transparent to the bonded substrate (sapphire substrate) 5 and absorbed by the adhesive (e.g., BCB) 4. For example, a laser (ultraviolet light) with a wavelength of 170 nm to 360 nm can be used as the removal laser 83.

[0082] Previously described Fig.10 , is a conceptual diagram of the case where the poorly bonded parts are removed by the above-mentioned LLO (laser lift-off). Fig.10 As shown in FIG. 1 , laser light is irradiated along the outline of the removal area (the portion of the light emitting element structure 3 included in the defective portion 10A of the bonded wafer 10). Fig.12 As shown, a minimum area of ​​a defective portion removed region 35 can be obtained. In other words, the defective portion can be completely removed while being controlled to a level where there is only a defective portion.

[0083] Next, the bonded wafer 10 is taken out from the laser processing unit, and the surface coated with the protective material 6 is turned upward and washed with pure water to remove the protective material 6. Fig.13In the illustrated junction type light emitting device wafer 20, the light emitting device structure 3 including the region 35 from which the defective portion has been removed is bonded to the bonded substrate 5 via the adhesive 4. The wafer 20 before the protective material 6 is removed can also be called a junction type light emitting device wafer.

[0084] The light emitting element structure 3 is a structure that becomes a micro LED, and can be subjected to element separation processing as shown below. An example of the processing will be described below.

[0085] A mask pattern is formed on the light emitting element structure 3 by photolithography, and the light emitting element structure 3 is subjected to element separation processing by ICP (inductively coupled plasma). Fig.14 As shown, the light emitting element structure 3 becomes an element separated from the separation groove 21 (the light emitting element structure after the element separation process, i.e., a bare crystal) 9. The gas used in ICP is, for example, chlorine and argon. The ICP process is performed, for example, twice: a step of exposing the BCB4 layer and a step of exposing a portion of the main surface of the second cladding layer 33.

[0086] In this embodiment, the case where a part of the main surface of the second cladding layer 33 is exposed is exemplified, but it is of course not limited to the case where a part of the main surface of the second cladding layer 33 is exposed, and of course the processing purpose is achieved as long as the active layer 32 is separated at least. Of course, the same effect can be obtained when a part of the main surface of the GaP window layer is exposed instead of the second cladding layer 33.

[0087] After the components are separated and processed, Fig.15 As shown, a protective film 91 is formed as the end surface treatment. In this embodiment, SiO2 is used as the protective film 91. The protective film 91 is not limited to SiO2, and any material can be selected as long as it can protect the end surface and has insulation properties. SiN x Or titanium oxide, magnesium oxide, etc. The protective film 91 is provided with an opening 92 that exposes a portion of the main surface of the first cladding layer 31 , and an opening 93 that exposes a portion of the main surface of the second cladding layer 33 .

[0088] After the protective film 91 is formed, Fig.16 As shown, electrodes 94 and 95 are formed to contact the first conductive layer or the second conductive layer respectively, and ohmic contact is formed by applying heat treatment. In this embodiment, the first conductive type is designed to be N-type, and the second conductive type is designed to be P-type. A metal containing Au and Si is used for the N-type electrode 94 that contacts the first cladding layer 31 as the N-type layer through the opening 92, and a metal containing Au and Be is used for the P-type electrode 95 that contacts the second cladding layer 33 as the P-type layer through the opening 93.

[0089] In this embodiment, although Au and Si metals are used as N-type electrodes, they are not limited to these materials, and the same results can be obtained even if Au and Ge metals are used. In addition, although Au and Be metals are used as P-type electrodes, they are not limited to these materials, and the same results can be obtained even if Au and Zn metals are used.

[0090] In addition, in the present embodiment, BCB is used as the adhesive 4, but the material of the adhesive 4 used in the present invention is not limited to BCB as long as it is a material that absorbs the removal laser 83. For example, when using a bonded substrate 5 that is transparent to the removal laser 83 having a wavelength of 170 nm to 360 nm, as long as the adhesive 4 has a light absorption boundary in the wavelength range of 170 nm to 360 nm, it can be easily sublimated by the removal laser 83 having a wavelength of 170 nm to 360 nm that can transmit through the bonded substrate 5. Examples of the adhesive 4 include silicone resin, epoxy resin, SOG (spin-on glass), polyimide, and amorphous fluorine resin (for example, Cytop (registered trademark)), etc., in addition to BCB. By using these adhesives, the light emitting element structure 3 and the bonded substrate 5 can be firmly bonded.

[0091] (Second Embodiment) In the second embodiment, the step of obtaining the bonded wafer 10 is the same as that of the first embodiment, but is different from the first embodiment in that the light emitting element structure 3 is subjected to element separation processing and electrode formation processing before the step of obtaining the removal map data.

[0092] The element separation process and the electrode formation process can be referred to as the above except that the defective part of the light emitting element structure 3 is not removed. Figure 14 to Figure 16 In the second embodiment, since the element separation (bare crystal) processing or electrode attachment is performed in a state where there is a convex defective part in the light emitting element structure 3, an element with a bad shape or size may be formed in the defective part. Such a defective part is removed later by irradiating with a removal laser based on the removal map data.

[0093] However, in the second embodiment, unlike the first embodiment, it is not suitable to obtain topological map data after the bare wafer is processed, and therefore only the first map data and the second map data are obtained.

[0094] Then, similarly to the first embodiment, the defective part is superimposed using the first map data and the second map data to create removal map data.

[0095] When removing the defective part, a protective material is applied on the surface of the element obtained by separating the light-emitting element structure of the bonded wafer, as in the first embodiment. And, in the same steps as in the first embodiment, a laser is irradiated from the sapphire substrate side to remove the defective part. Then, as in the first embodiment, the protective material is removed by washing with water. Thus, a bonded light-emitting element wafer can be obtained, in which the light-emitting element structure (element) with the defective part removed is bonded to the bonded substrate by an adhesive.

[0096] If the manufacturing method of the bonded light emitting element wafer of the present invention is as described above, it is possible to simply selectively remove the defective parts of the light emitting element structure without using a mechanical method and without affecting the good parts of the light emitting element structure (such as other bare crystal areas). In addition, according to the present invention, all parts of the light emitting element structure that are included in the defective parts of the bonded wafer can be removed.

[0097] In particular, as in the first embodiment, by removing the poorly bonded portion (particularly a convex poorly bonded portion) before entering into the device process such as the element separation process, the poorly bonded portion of lithography accuracy around the poorly bonded portion can be reduced.

[0098] In addition, in the second embodiment, defective portions of the light emitting element structure can be selectively removed simply without using a mechanical method and without affecting good portions of the light emitting element structure (eg, other bare die regions).

[0099] <Micro LED Transfer Method> The micro-LED transfer method of the present invention is a micro-LED transfer method, which transfers the micro-LED from a bonded light-emitting element wafer containing the micro-LED to a transfer substrate, wherein a bonded light-emitting element wafer containing a light-emitting element structure that has undergone element separation processing is manufactured by the above-described method for manufacturing the bonded light-emitting element wafer of the present invention; and the light-emitting element structure as the micro-LED is transferred from the bonded light-emitting element wafer to the transfer substrate.

[0100] As described above, in the method for manufacturing a junction-type light-emitting element wafer of the present invention, it is possible to selectively remove defective parts (e.g., defective junction parts and defective parts of element characteristics) in the light-emitting element structure contained in the junction-type light-emitting element wafer, thereby manufacturing a junction-type light-emitting element wafer including a light-emitting element structure from which the defective parts have been removed. Therefore, according to the method for transferring a micro-LED of the present invention, it is possible to prevent the transfer of defective light-emitting element structures, i.e., defective micro-LEDs. [Example]

[0101] Hereinafter, the present invention will be specifically described using Examples and Comparative Examples, but the present invention is not limited thereto.

[0102] (First embodiment) In the first embodiment, a junction type light emitting device wafer is manufactured by the same steps as those of the first embodiment described above. Specifically, the steps are as follows.

[0103] First, in the same steps as previously described, a Figure 2 The EPW structure shown is EPW100.

[0104] Next, BCB4 with a designed film thickness of 0.6 μm was coated on the light emitting element structure 3 of EPW100 by spin coating.

[0105] This is stacked against a sapphire wafer as the wafer to be bonded 5 , and then thermocompression-bonded to produce an EPW bonded substrate 200 .

[0106] Next, the GaAs starting substrate 1 is removed by wet etching to expose the first etching stop layer, and the etchant is switched to remove the second etching stop layer. Thus, the etching stop layer 2 is removed to expose the first cladding layer 31, thereby producing a bonding wafer (EP bonding substrate) 10 ( Figure 4 and Figure 5 ).

[0107] Next, the removal map data is created using the following steps.

[0108] The laser with a wavelength of 532nm and a spot diameter of 100μm is irradiated to the entire area of ​​the bonded wafer 10 at a pitch of 25μm, and the PL spectrum is collected to produce map data. In this embodiment, the design wavelength of EPW is designed to be 632nm, and the positions within the range of 632±5nm are taken as qualified points, and the wavelength domain outside the range is taken as unqualified points, thereby producing the first map data.

[0109] In addition, laser light with an oscillation wavelength of 532 nm is irradiated from an oblique direction to the surface of the light emitting element structure 3 side of the bonded wafer 10. Using a system that places a light receiver at a position in the reflection direction at the same angle as the laser incident angle, the entire surface of the wafer is irradiated with laser light at a pitch of 25 μm, and topological data is collected. Using the height tolerance as a threshold, topological map data is created, with points within the tolerance as qualified points and other points as unqualified points.

[0110] In addition, the bonded wafer 10 is photographed from the sapphire substrate 5 side with a CCD camera, and second map data is produced for judging pass / fail based on contrast difference with a 25 μm pitch grid.

[0111] The defective parts of the first map data, the topological map data, and the second map data obtained in the above manner are superimposed to create removal map data.

[0112] Next, Hogomax (trademark) manufactured by DISCO is applied by spin coating on the substrate-removed surface of the light-emitting element structure 3 of the bonded wafer 10. Figure 6 A protective material 6 is applied as shown.

[0113] by Figure 7 The bonding wafer receiving fixture 7 shown in FIG. Figure 8 As shown, the bonded wafer 10 coated with the protective material 6 is held and introduced into the laser processing unit with the coated surface of the protective material 6 facing downward. Figure 8 As shown, the wafer is held in such a manner that the wafer receiving groove portion 71 of the bonding wafer receiving jig 7 abuts against the light emitting element structure non-bonding region 51 exposed on the sapphire substrate 5 .

[0114] In the laser processing department, such as Fig.10 and Fig.11 As shown, from the sapphire substrate 5 side, KrF excimer laser with a wavelength of 248 nm is irradiated only to the area defined as the defective part 10A (and almost only a slight overflow portion of the defective part) according to the removal map data, thereby removing the defective part.

[0115] Next, the wafer is taken out from the laser processing unit, and the coating surface of the protective material 6 is turned upward and cleaned with pure water. Fig.13 The protective material 6 is shown removed.

[0116] Next, a mask pattern is formed on the light emitting element structure 3 by photolithography, and an element separation process is performed by ICP using chlorine gas and argon gas. The ICP process is performed twice: a step of exposing the BCB4 layer and a step of exposing a portion of the main surface of the second cladding layer 33. By this element separation process, Fig.14 As shown, the light emitting element structure 3 becomes an element separated from the separation groove 21 (a light emitting element structure after the element separation process) 9 .

[0117] After the components are separated and processed, Fig.15 As shown, a SiO 2 protective film 91 is formed as the end surface treatment, and an opening 92 exposing a part of the main surface of the first cladding layer 31 and an opening 93 exposing a part of the main surface of the second cladding layer 33 are provided in the protective film 91 .

[0118] After the protective film 91 is formed, Fig.16As shown, electrodes 94 and 95 are formed to contact the first conductive type layer or the second conductive type layer respectively, and a heat treatment is applied to form an ohmic contact. In this embodiment, the first conductive type is designed to be N-type, and the second conductive type is designed to be P-type. A metal containing Au and Si is used for the N-type electrode 94 contacting the first cladding layer 31 as the N-type layer, and a metal containing Au and Be is used for the P-type electrode 95 contacting the second cladding layer 33 as the P-type layer.

[0119] Through the above methods, we can obtain Fig.16 The structure shown is a junction type light emitting element wafer 20 of the first embodiment.

[0120] (Second embodiment) In the second example, a junction type light emitting device wafer is manufactured by the same steps as the second embodiment described above.

[0121] That is, in the second embodiment, the junction type light emitting element wafer of the second embodiment is manufactured in the same manner as the first embodiment, except that the element separation processing and electrode formation processing are performed on the light emitting element structure 3 before the step of obtaining the removal map data, and the topology map data is not obtained.

[0122] (Comparative Example) In the comparative example, a junction type light emitting element wafer of the comparative example was manufactured in the same manner as in the first embodiment except that the defective portion of the light emitting element structure was not removed.

[0123] That is, in the comparative example, the step of obtaining the bonded wafer 10 is performed in the same manner as in the first embodiment, and the element separation process and the electrode formation process are performed in the same manner as in the second embodiment. However, in the comparative example, unlike in the second embodiment, the map data is not prepared and removed, so the defective part of the light emitting element structure is maintained as it is.

[0124] (Evaluate) Next, as Table 1, there is shown a table comparing the removal rate of the convex defective portion and the yield of the number of bare chips without any problem in the final mounting.

[0125]

Table 1

[0126] In the first embodiment, when the convex defective part has been removed, the defective part is connected to the good part because it is in the wafer state. When the BCB of the defective part sublimates and disconnects the light-emitting element structure, the crack sometimes enters the adjacent good part, so the removal rate is slightly higher than 100%. In the case of the second embodiment, because the defective part has been removed in the bare crystal state, even if the BCB of the defective part sublimates and disconnects the light-emitting element structure, the impact will not propagate to the adjacent good part because there is a separation groove between the bare crystals, and the recognized defective area is roughly the same as the removal area, so the removal rate is 100%. In the case of the comparative example, since it is not removed, the removal rate is 0%.

[0127] In addition, the above Table 1 shows the mounting bare die yield when 10 bonding type light emitting element wafers obtained in the first and second embodiments and the comparative example are put into the mounting (transfer) step.

[0128] The number in brackets is the deviation of 10 wafers, and the number outside brackets is the average value. When the bare crystal is put into the transfer step after removing the defective part by the method of the first embodiment or the second embodiment, the bare crystal installation yield (the number of bare crystals that are effective as devices / the number of bare crystals that can be obtained from one piece) exceeds 90% on average. In contrast, in the comparative example in which the protruding defective part is not removed before transfer, in the step of pressing the bare crystal against the transfer substrate during transfer, due to the stress concentration on the protruding defective part, not only the defective bare crystal but also the surrounding bare crystals are damaged by cracks or notches. Therefore, the yield is greatly reduced compared with the embodiment in which only the protruding defective part can be removed.

[0129] As shown above, the first embodiment and the second embodiment of performing LLO removal on defective parts before transferring the bare die to the transfer substrate and then putting the bare die into the mounting step can further improve the final mounting yield.

[0130] Furthermore, this specification includes the following aspects. [1] A method for manufacturing a bonded light-emitting element wafer, wherein a light-emitting element structure to be a micro-LED is bonded to a bonded substrate that is transparent to the removal laser by means of an adhesive that absorbs a removal laser, the method comprising the following steps: bonding the light-emitting element structure to the bonded substrate by means of the adhesive to obtain a bonded wafer; optically inspecting defective portions of the bonded wafer to produce removal map data; and, based on the removal map data, irradiating the removal laser from the bonded substrate side with respect to the defective portion of the bonded wafer, causing a portion of the adhesive contained in the defective portion to absorb the removal laser, causing a portion of the adhesive contained in the defective portion to sublime, thereby removing a portion of the light-emitting element structure contained in the defective portion to obtain the bonded light-emitting element wafer. [2] According to the manufacturing method of the bonded light-emitting element wafer described in [1], in the step of preparing the removal map data, the following steps are performed: obtaining the photoluminescence spectrum of the bonded wafer, and preparing the first map data related to the defective part based on the peak wavelength, peak intensity and / or peak half-value width as the judgment basis; and photographing the bonded wafer from the bonded substrate side with a CCD camera, and preparing the second map data related to the defective part based on the color tone of the image obtained by the photographing; and using the first map data and the second map data to prepare the removal map data. [3] The method for manufacturing a bonded light-emitting element wafer according to [2], wherein the light-emitting element structure is subjected to element separation processing; and the removal map data is prepared for the bonded wafer including the light-emitting element structure after the element separation processing. [4] The method for manufacturing a bonded light-emitting element wafer according to [2], wherein, in the step of preparing removal map data, the following steps are also performed: irradiating the surface of the light-emitting element structure of the bonded wafer with a topology detection laser from an inclined direction to obtain topology data, and preparing topology map data related to the defective portion based on the topology data; using the first map data, the second map data and the topology map data to prepare removal map data related to the defective portion; and after removing the portion of the light-emitting element structure contained in the defective portion, performing element separation processing on the light-emitting element structure. [5] The method for manufacturing a junction-type light-emitting element wafer according to any one of [1] to [4], wherein a laser having a wavelength of 170 nm to 360 nm is used as the removal laser. [6] The method for manufacturing a junction-type light-emitting element wafer according to any one of [1] to [5], wherein the adhesive used is an adhesive having a light absorption edge in a wavelength range of 170 nm to 360 nm. [7] According to any one of [1] to [6], the adhesive used is an adhesive selected from the group consisting of benzocyclobutene, silicone resin, epoxy resin, SOG, polyimide and amorphous fluorine-based resin. [8] The method for manufacturing a junction-type light-emitting element wafer according to any one of [1] to [7], wherein a protective material is applied to the light-emitting element structure before removing the portion of the light-emitting element structure included in the defective portion. [9] The method for manufacturing a junction-type light-emitting element wafer according to [8], wherein the protective material is a protective material containing polyvinyl acetate or a protective material containing polyvinyl alcohol.

[10] A method for transferring a micro LED, wherein the micro LED is transferred from a bonded light-emitting element wafer containing the micro LED to a transfer substrate, wherein a bonded light-emitting element wafer containing the light-emitting element structure that has undergone the element separation process is manufactured by the method for manufacturing a bonded light-emitting element wafer described in [3] or [4]; and the light-emitting element structure that is the micro LED is transferred from the bonded light-emitting element wafer to the transfer substrate.

[0131] In addition, the present invention is not limited to the above-mentioned embodiments. The above-mentioned embodiments are examples, and any technology having substantially the same structure as the technical concept described in the scope of the claims of the present invention and achieving the same effect is included in the technical scope of the present invention.

Claims

1. A method for manufacturing a bonded light emitting element wafer, wherein a light emitting element structure to be a micro-LED is bonded to a bonded substrate transparent to the removal laser by means of an adhesive that absorbs a removal laser, wherein: The following steps are involved: Bonding the light emitting element structure to the bonded substrate by means of the adhesive to obtain a bonded wafer; optically inspecting defective parts of the bonded wafer and creating map data for removal; as well as Based on the removal map data, the removal laser is irradiated from the bonded substrate side at the defective portion of the bonded wafer, so that the portion of the adhesive contained in the defective portion absorbs the removal laser and the portion of the adhesive contained in the defective portion sublimates, thereby removing the portion of the light-emitting element structure contained in the defective portion to obtain the bonded light-emitting element wafer.

2. The method for manufacturing a junction type light emitting element wafer according to claim 1, wherein: In the step of preparing the removal map data, the following steps are performed: Obtaining a photoluminescence spectrum of the bonded wafer, and using a peak wavelength, a peak intensity and / or a peak half-value width as a judgment reference to generate first map data related to the defective portion; and photographing the bonded wafer from the bonded substrate side with a CCD camera, and creating second map data related to the defective portion based on the color tone of the image obtained by photographing; The removal map data is created using the first map data and the second map data.

3. The method for manufacturing a junction type light emitting element wafer according to claim 2, wherein: performing a component separation process on the light emitting element structure; The removal map data is created for the bonded wafer including the light emitting element structure after the element separation process.

4. The method for manufacturing a junction type light emitting element wafer according to claim 2, wherein: In the step of preparing the removal map data, the following steps are further performed: irradiating a topology detection laser on the surface of the light emitting element structure of the bonded wafer from an oblique direction to obtain topology data, and creating topology map data related to the defective portion based on the topology data; creating removal map data related to the defective part using the first map data, the second map data, and the topological map data; After removing the portion of the light emitting element structure included in the defective portion, the light emitting element structure is subjected to element separation processing.

5. The method for manufacturing a junction type light emitting element wafer according to claim 1, wherein: As the removal laser, a laser having a wavelength of 170 nm to 360 nm is used.

6. The method for manufacturing a junction type light emitting element wafer according to claim 5, characterized in that: As the adhesive, an adhesive having a light absorption edge in a wavelength range of 170 nm to 360 nm is used.

7. The method for manufacturing a junction type light emitting element wafer according to claim 6, wherein: As the adhesive, an adhesive selected from the group consisting of benzocyclobutene, silicone resin, epoxy resin, SOG (spin-on-glass), polyimide, and amorphous fluorine-based resin is used.

8. The method for manufacturing a junction-type light-emitting element wafer according to any one of claims 1 to 7, characterized in that: Before removing the portion of the light emitting element structure included in the defective portion, a protective material is applied to the light emitting element structure.

9. The method for manufacturing a junction type light emitting element wafer according to claim 8, characterized in that: As the protective material, a protective material containing polyvinyl acetate or a protective material containing polyvinyl alcohol is used.

10. A method for transferring micro LEDs, from a junction-type light-emitting element wafer containing micro LEDs, to a transfer substrate, characterized in that: A junction type light emitting element wafer including the light emitting element structure subjected to the element separation process is manufactured by the method for manufacturing a junction type light emitting element wafer according to claim 3 or 4; The light emitting element structure serving as the micro LED is transferred from the junction type light emitting element wafer to the transfer substrate.

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